Studies have indicated that P2X7 receptor are involved in the progression of non-small cell lung cancer (NSCLC). Therefore, this study sought to explore how modulating P2X7 receptor expression levels affect the biological function of NSCLC and its underlying mechanisms. Recombinant plasmids with P2X7 receptor overexpression or knockdown were constructed and transfected into LLC and LA795 cells, and the biological function changes of these two cells were assessed in vitro. Subsequently, stable cell lines (overexpression or knockdown of P2X7 receptor) were screened, and their tumorigenicity was detected in vivo. The findings of this study demonstrate that both LLC and LA795 cells expressed functional P2X7 receptors, and overexpression of P2X7 receptors promoted the migration and invasion of LLC and LA795 cells. Conversely, the knockdown of the P2X7 receptor yielded contrasting effects. The mechanism involved phosphatidylinositol 3-kinase/protein kinase B/glycogen synthase kinase 3 beta (PI3K/Akt/GSK-3β), c-Jun N-terminal kinase (JNK) signaling pathway and epithelial-mesenchymal transition (EMT). In addition, the knockdown of the P2X7 receptor suppressed cell proliferation and promoted apoptosis in both cells (LLC and LA795). In vivo experiments corroborated these findings, demonstrating that overexpression of the P2X7 receptor promoted tumor growth while its knockdown inhibited tumor growth. The expression levels of related signaling proteins (PI3K/Akt/GSK-3β, JNK, and EMT) in vivo were consistent with the trends observed in vitro. In conclusion, our results suggest that downregulating P2X7 receptor expression can effectively suppress tumor growth, invasion, and migration in NSCLC. Our results suggest that the P2X7 receptor has the potential as a therapeutic target for NSCLC.

Small cell lung cancer (SCLC) is an aggressive neuroendocrine malignancy with ~7% 5-year overall survival reflecting early metastasis and rapid acquired chemoresistance. Immunotherapy briefly extends overall survival in ~15% cases, yet predictive biomarkers are lacking. Targeted therapies are beginning to show promise, with a recently approved delta-like ligand 3 (DLL3)-targeted therapy impacting the treatment landscape. The increased availability of patient-faithful models, accumulating human tumour biobanks and numerous comprehensive molecular profiling studies have collectively facilitated the mapping and understanding of substantial intertumoural and intratumoural heterogeneity. Beyond the almost ubiquitous loss of wild-type p53 and RB1, SCLC is characterized by heterogeneously mis-regulated expression of MYC family members, yes-associated protein 1 (YAP1), NOTCH pathway signalling, anti-apoptotic BCL2 and epigenetic regulators. Molecular subtypes are based on the neurogenic transcription factors achaete-scute homologue 1 (ASCL1) and neurogenic differentiation factor 1 (NEUROD1), the rarer non-neuroendocrine transcription factor POU class 2 homeobox 3 (POU2F3), and immune- and inflammation-related signatures. Furthermore, SCLC shows phenotypic plasticity, including neuroendocrine-to-non-neuroendocrine transition driven by NOTCH signalling, which is associated with disease progression, chemoresistance and immune modulation and, in mouse models, with metastasis. Although these features pose substantial challenges, understanding the molecular vulnerabilities of transcription factor subtypes, the functional relevance of plasticity and cell cooperation offer opportunities for personalized therapies informed by liquid and tissue biomarkers.

Lung adenocarcinoma (LUAD) is the most prevalent subtype of lung cancer. Herein, we probed into the role of E3 ubiquitin protein ligase family member 1 (HERC1) in promoting ferroptosis and inhibiting LUAD cell proliferation by regulating RAF proto-oncogene serine/threonine-protein kinase (C-RAF).

In cultured human normal lung epithelial cells and non-small cell lung adenocarcinoma cell lines, HERC1 expression was determined by RT-qPCR and Western blot tests. PC-9 and Calu-3 cells were transfected with oe-HERC1, oe-C-RAF or their negative controls. Reactive oxygen species (ROS), malondialdehyde (MDA), glutathione (GSH), and Fe2+ levels were assessed by biochemical assays. Cell viability, death, and proliferation were evaluated by CCK-8, LDH and colony formation assays, followed by assessments of HERC1-C-RAF interaction, C-RAF ubiquitin level, and C-RAF protein stability.

HERC1 was poorly expressed in LUAD cells. HERC1 promoted LUAD cell ferroptosis and repressed their proliferation and migration, corresponding to reduced levels of system xc-, GPX4, and GSH, as well as elevated levels of ROS, MDA, Fe2+, and ACSL4. LUAD cells overexpressing HERC1 displayed decreased C-RAF protein level, HERC1-C-RAF interaction, elevated C-RAF ubiquitin level, and accelerated C-RAF protein degradation, indicating that HERC1 facilitated C-RAF ubiquitin degradation and attenuated C-RAF protein stability via interaction with C-RAF. C-RAF overexpression partially abrogated the regulatory impact of HERC1 on LUAD cell ferroptosis and proliferation.

HERC1 expedites C-RAF ubiquitin degradation by interacting with C-RAF, which consequently promotes ferroptosis, thereby inhibiting LUAD cell proliferation.

Lung cancer is a leading cause of global cancer mortality. Clinical observations reveal that histological transformation from non-small cell lung cancer (NSCLC) to small cell lung cancer (SCLC) is accompanied by mutations in TP53 and RB1. By applying gradually increasing cisplatin concentrations to mimic the escalating drug pressure within the tumor microenvironment, this study investigated the link between phenotypic transformation to SCLC in cisplatin-resistant human lung adenocarcinoma cells and alterations in cellular energy production pathways.

We established two cisplatin-resistant NSCLC cell lines with varying resistance levels. RNAseq analyses identified TP53 and RB1 gene mutations. Comprehensive functional assays were performed to characterize A549/DDP1 μg/mL and A549/DDP3 μg/mL cells, focusing on proliferation and migratory capabilities. Cellular bioenergetics were assessed through glycolysis and oxidative phosphorylation analyses. Western blotting was employed to examine epithelial-mesenchymal transition (EMT), glucose metabolism, and lipid metabolism markers. Cell cycle distribution was analyzed by flow cytometry. Additionally, a xenograft mouse model was developed for in vivo validation.

TP53 and RB1 mutations were associated with cisplatin concentration-dependent phenotypic transformation, with A549/DDP cells acquiring a more aggressive SCLC-like phenotype (In the article we call the A549/DDPSCLC cells). Analysis of cell bioenergetics profiling and Western blot analyses revealed enhanced glucose metabolism in A549/DDP1 μg/mL cells, while A549/DDPSCLC cells exhibited predominant lipid metabolism. Compound3K and Etomoxir specifically inhibit the activity of PKM2 and CPT1A, respectively, with Etomoxir demonstrating substantially inhibited A549/DDPSCLC cells growth and more cell cycle arrest in the G0/G1 phase. Combinatorial of Compound3K and Etomoxir effectively induced cell death in A549/DDPSCLC phenotype cells in vitro. Etomoxir alone or combined with Compound3K significantly inhibited tumor growth in vivo, with enhanced efficacy in the combination group.

This study provides the first evidence of cisplatin concentration-dependent metabolic reprogramming during NSCLC-to-SCLC transformation. We identified a phenotypic transition from NSCLC to SCLC accompanied by a metabolic shift from glucose to fatty acid metabolism, offering new insights into therapeutic strategies for treatmentresistant lung cancer.

As a common malignancy of the lower respiratory tract, non-small cell lung cancer (NSCLC) represents a major oncological challenge globally, characterized by high incidence and mortality rates. Recent research highlights the critical involvement of somatic mutations in the onset and development of NSCLC. Stratification of NSCLC patients based on somatic mutation data could facilitate the identification of patients likely to respond to personalized therapeutic strategies. However, stratification of NSCLC patients using somatic mutation data is challenging due to the sparseness of this data. In this study, based on sparse somatic mutation data from 4581 NSCLC patients from the Memorial Sloan Kettering Cancer Center (MSKCC) database, we systematically evaluate the metabolic pathway activity in NSCLC patients through the application of network propagation algorithm and computational biology algorithms. Based on these metabolic pathways associated with prognosis, as recognized through univariate Cox regression analysis, NSCLC patients are stratified using the deep clustering algorithm to explore the optimal classification strategy, thereby establishing biologically meaningful metabolic subtypes of NSCLC patients. The precise NSCLC metabolic subtypes obtained from the network propagation algorithm and deep clustering algorithm are systematically evaluated and validated for survival benefits of immunotherapy. Our research marks progress towards developing a universal approach for classifying NSCLC patients based solely on somatic mutation profiles, employing deep clustering algorithm. The implementation of our research will help to deepen the analysis of NSCLC patients' metabolic subtypes from the perspective of tumor microenvironment, providing a strong basis for the formulation of more precise personalized treatment plans.

Lung cancer is a leading cause of mortality in oncological classifications, yet the impact of various risk factors on lung cancer mortality (LCM) in non-smokers remains unclear. This study aims to weigh out the diverse impact of multiple risk factors on LCM rates and identify trends in LCM rates worldwide. We initially employed Random Forest Tree (RFT) and Gradient Boosting Regression (GBR) to identify common primary factors influencing LCM. After eliminating four common primary factors, a comparative analysis between partial and Pearson correlations was conducted to filter out significant factors in the correlations between risk factors and LCM rates across 204 countries from 2005 to 2019. The findings show that excluding the impacts of occupational exposure to arsenic, smoking, residential radon, occupational exposure to silica, occupational exposure to asbestos, high systolic blood pressure, secondhand smoke, child wasting, and alcohol use had a considerably greater impact on LCM than particular matter pollution (PM2.5). Furthermore, a Multiple Joinpoint Regression analysis identified increasing trends of LCM rates in the 142 countries (e.g., China and India); decreasing trends in 38 countries (e.g., Denmark and Norway), and stable trends in 24 countries (e.g., Sudan, Mali, and Australia). This research suggests that in addition to considering the effects of occupational exposure to arsenic, smoking, residential radon, and occupational exposure to silica on LCM rates, occupational exposure to asbestos, high systolic blood pressure, secondhand smoke, child wasting, and alcohol use should be considered in lung cancer prevention strategies, especially in countries with increasing trends of LCM rates.

Small cell lung cancer (SCLC) is an aggressive neuroendocrine tumor. Lung cancer patients with ALK and EML4 fusions respond significantly to ALK inhibitors. The EML4-ALK fusion gene mutation is the result of an inversion of chromosome 2, which juxtaposes the 5 end of the EML4 gene with the 3 end of the ALK gene. In SCLC, the frequency of fusion genes is very low, and to the best of our knowledge, only four cases of ALK fusion gene mutations in SCLC have been reported. In this report, we describe the treatment of a 74-year-old female patient with SCLC who developed recurrence of hilar lymph node metastasis three years after surgical resection. Postoperative NGS showed that this patient is a SCLC patient harboring a rare EML4-ALK fusion mutation, and a satisfactory 43-month overall survival (OS) was achieved after treatment with ensartinib targeting the EML4-ALK fusion gene mutation. The ALK-TKI may be a new treatment option for these patients. This article provides a therapeutic reference.

A fraction of lung adenocarcinoma patients with gene mutations who receive targeted therapy would experience acquired resistance and undergo small cell lung cancer (SCLC) transformation. The mechanisms behind the transformation of tumor pathological types and the treatment strategies are not fully clear. There have been case reports of the transformation from adenocarcinoma to SCLC, but the partial transformation from adenocarcinoma to SCLC has not been reported. We reported a case of a patient with partial transformation from lung adenocarcinoma to SCLC for the first time. The patient was diagnosed as lung adenocarcinoma with epidermal growth factor receptor (EGFR) 19 exon mutation and Tumor protein p53 (TP53) mutation. She received Epithelial growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) treatment. However, the tumor progression occurred and the lung aspiration pathology revealed a transformation from non-small cell lung cancer (NSCLC) to SCLC. The treatment regimen was changed to cisplatin and etoposide (EP) chemotherapy, resulting in a 2-month PFS. It was worth mentioning that adenocarcinoma cells were found in the patient's emerging pericardial effusion, suggesting the co-existence of both adenocarcinoma and SCLC components. This is the first report of partial transformation from NSCLC to SCLC in the context of definitive pathology. It highlights that when no more pathological biopsy is feasible, we should be alert to the partial transformation and adopt the appropriate treatment.

Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) effectively treat EGFR-mutant lung adenocarcinoma, demonstrating initial efficacy but eventually leading to acquired resistance. Small cell transformation is a rare resistance mechanism to EGFR-TKIs in lung adenocarcinoma, which can complicate clinical diagnosis and treatment. We present a patient with lung adenocarcinoma who underwent a prior pneumonectomy and adjuvant chemotherapy and was treated with osimertinib after the recurrence of lung cancer. Small cell transformation occurred approximately 20 months after starting osimertinib treatment. After this transformation, the patient underwent lung radiotherapy and cisplatin-etoposide chemotherapy, which stabilized the disease. Following the confirmation of small cell lung cancer (SCLC) via thyroid puncture, treatments with irinotecan, irinotecan plus atezolizumab, thyroid radiotherapy, adrenal radiotherapy, and head radiotherapy were sequentially administered, yet the disease continued to progress. The patient succumbed to the disease in May 2023 because of progression and organ failure, with an overall survival of 52.7 months, including 16 months post small cell transformation. This case highlights the possibility of osimertinib causing lung adenocarcinoma to transform into SCLC and underscores rebiopsies' importance in identifying resistance mechanisms to EGFR-TKIs. Increased levels of neuron-specific enolase and pro-gastrin releasing peptide can signal early transformation into SCLC.

Neoantigen vaccines are under investigation for various cancers, including epidermal growth factor receptor (EGFR)-driven lung cancers1,2. We tracked the phylogenetic history of an EGFR mutant lung cancer treated with erlotinib, osimertinib, radiotherapy and a personalized neopeptide vaccine (NPV) targeting ten somatic mutations, including EGFR exon 19 deletion (ex19del). The ex19del mutation was clonal, but is likely to have appeared after a whole-genome doubling (WGD) event. Following osimertinib and NPV treatment, loss of the ex19del mutation was identified in a progressing small-cell-transformed liver metastasis. Circulating tumour DNA analyses tracking 467 somatic variants revealed the presence of this EGFR wild-type clone before vaccination and its expansion during osimertinib/NPV therapy. Despite systemic T cell reactivity to the vaccine-targeted ex19del neoantigen, the NPV failed to halt disease progression. The liver metastasis lost vaccine-targeted neoantigens through chromosomal instability and exhibited a hostile microenvironment, characterized by limited immune infiltration, low CXCL9 and elevated M2 macrophage levels. Neoantigens arising post-WGD were more likely to be absent in the progressing liver metastasis than those occurring pre-WGD, suggesting that prioritizing pre-WGD neoantigens may improve vaccine design. Data from the TRACERx 421 cohort3 provide evidence that pre-WGD mutations better represent clonal variants, and owing to their presence at multiple copy numbers, are less likely to be lost in metastatic transition. These data highlight the power of phylogenetic disease tracking and functional T cell profiling to understand mechanisms of immune escape during combination therapies.

Anlotinib, an anti-angiogenic agent, has demonstrated significant anti-tumor effects in non-small cell lung cancer (NSCLC). However, whether anlotinib exerts its anti-tumor activity in NSCLC through ferroptosis, and its underlying mechanisms, remain unclear. This study revealed that anlotinib effectively inhibited the proliferation of NSCLC cells in a time- and dose-dependent manner. Treatment with anlotinib resulted in increased levels of ferroptosis targets (lipid reactive oxygen species and malondialdehyde) and p53 protein expression, while decreasing glutathione levels and the protein expression of solute carrier family 7 member 11 (xCT) and glutathione peroxidase 4 (GPX4). Notably, the ferroptosis inhibitor, Ferrostatin-1 (Fer-1), or the p53 inhibitor, Pifithrin-α (PFT-α), reversed the observed effects on ferroptosis induction in NSCLC cells. Consistently, our in vivo studies showed accelerated tumor growth rates for the anlotinib/Fer-1 group and the anlotinib/PFT-α group compared with administration of anlotinib alone. However, anlotinib-induced ferroptosis was suppressed in p53-deficient cells. Collectively, these findings confirm that anlotinib exerts potent anti-tumor effects both in vitro and in vivo by inducing ferroptosis by modulating the p53/xCT/GPX4 pathway specifically within NSCLC cells.

In the clinical management of lung cancer, radiotherapy remains a cornerstone of multimodal treatment strategies, often used alongside surgery or in combination with systemic therapies such as chemotherapy, tyrosine kinase inhibitors, and immune checkpoint inhibitors. While conventional imaging modalities like computed tomography (CT) and magnetic resonance imaging (MRI) continue to play a central role in staging, response assessment, and radiotherapy planning, advanced imaging techniques, particularly [18F]FDG PET/CT, are being increasingly integrated into routine clinical practice. These advanced techniques address the limitations of standard imaging by providing insight into molecular and metabolic tumor characteristics, enabling precise tumor visualization, accurate target volume delineation, and early treatment response assessment. This review examines the role of radiotherapy in the multidisciplinary management of lung cancer, detailing current concepts of morphological and functional imaging for staging and treatment planning. It also highlights the growing importance of PET-based radiotherapy planning, emphasizing its contributions to target volume definition and predictive value for treatment outcomes. Recent methodological advances, including the integration of artificial intelligence (AI), radiomics, technical innovations, and novel PET ligands, are discussed, highlighting their potential to improve the precision, efficacy, and personalization of lung cancer radiotherapy planning.

Lung cancer remains a leading cause of cancer-related deaths worldwide, with low survival rates often attributed to late-stage diagnosis. To address this critical health challenge, researchers have developed computer-aided diagnosis (CAD) systems that rely on feature extraction from medical images. However, accurately identifying the most informative image features for lung cancer detection remains a significant challenge. This study aimed to compare the effectiveness of both hand-crafted and deep learning-based approaches for lung cancer diagnosis. We employed traditional hand-crafted features, such as Gray Level Co-occurrence Matrix (GLCM) features, in conjunction with traditional machine learning algorithms. To explore the potential of deep learning, we also optimized and implemented a Bidirectional Long Short-Term Memory (Bi-LSTM) network for lung cancer detection. The results revealed that the highest performance using hand-crafted features was achieved by extracting GLCM features and utilizing Support Vector Machine (SVM) with different kernels, reaching an accuracy of 99.78% and an AUC of 0.999. However, the deep learning Bi-LSTM network surpassed both methods, achieving an accuracy of 99.89% and an AUC of 1.0000. These findings suggest that the proposed methodology, combining hand-crafted features and deep learning, holds significant promise for enhancing early lung cancer detection and ultimately improving diagnosis systems.

Small-cell transformation is an uncommon mechanism of tyrosine receptor kinase inhibitor (TKI) resistance in epidermal growth factor receptor (EGFR)-mutant lung adenocarcinomas. This study aims to assess the dynamic changes in the molecular landscape and Rb1 functional status in EGFR-mutant lung adenocarcinomas transforming to small-cell carcinomas post-treatment with EGFR-TKIs. This is an ambispective study (2019-2023) wherein the baseline and post-TKI biopsies of EGFR-mutant lung adenocarcinomas with small-cell transformation were subject to Rb1 immunohistochemistry and 72-gene targeted panel next-generation sequencing. Rb1-deficiency was defined as Rb1 protein loss or Rb1retained/p16high/Cyclin-D1low protein expression profile with RB1 mutations. A cohort of EGFR-mutant lung adenocarcinomas without small-cell transformation was included for Rb1 status comparison. Small-cell transformation was diagnosed in 9 patients (10%, 9/84) on their post-TKI biopsy. All their tested baseline adenocarcinoma (n = 7) and post-TKI small-cell carcinoma (n = 9) samples were Rb1-deficient, with additional TP53 (11/11) and PTEN mutations (2/11). Eighteen paired samples from 9 patients without small-cell transformation revealed Rb1-deficiency in one patient (1/9) only. Baseline functional inactivation of Rb1 is nearly universal in EGFR-mutant adenocarcinomas transforming to small-cell carcinomas post-EGFR TKI suggesting that Rb1 loss is prerequisite for small-cell transformation. However, it is likely not sufficient as not all adenocarcinomas with baseline Rb1 loss transform into small-cell carcinomas. Except for TP53 and PTEN, recurrent mutations in other common oncogenes tested were not detected at baseline or at progression. Within the limitation of a small sample size, specific molecular events that drive small-cell transformation remain unclear.

Almonertinib, a third-generation epidermal growth factor receptor tyrosine kinase inhibitor, is selective for both epidermal growth factor receptor tyrosine kinase inhibitor-sensitizing and T790M resistance mutations. However, resistance to the third-generation EGFR-TKIs is still inevitable. Econdary EGFR mutations, and bypass pathway activation have been reported with Almonertinib therapy. This article presents a rare case report of a patient with EGFR L861Q positive adenosquamous lung carcinoma who transformed into large cell neuroendocrine carcinoma following treatment with Almonertinib. The patient exhibited disease progression 8 months after initiating Almonertinib treatment, and a blood genetic test revealed mutations in EGFR L861Q and EGFR L858R. A subsequent lung biopsy after progression confirmed the diagnosis of large cell neuroendocrine carcinoma, and subsequently treatment with cisplatin and etoposide was effective. Transformation into neuroendocrine carcinoma is one of the mechanisms behind resistance to Almonertinib in adenosquamous lung carcinoma. EGFR mutations may persist even after transformation into neuroendocrine carcinoma. For non-small cell lung cancer patients undergoing Almonertinib therapy, this case report emphasizes the importance of performing a timely pathological biopsy upon the emergence of resistance.

The treatment landscape of non-small cell lung cancer (NSCLC) has shifted significantly from empirical, histology-driven, and clinician-directed cytotoxic regimens to a stratified approach predicated on molecular profiling of tumor genetics and immune biomarkers, by the former can indicate targeted therapy that bull's eye hits the arrow, while the latter can hint the benefit amplitude of immune checkpoint inhibitors (ICBs). While third-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) have become the cornerstone of frontline therapy for patients harboring classic sensitive EGFR mutations, all tumors ultimately develop acquired resistance to these approaches, which can be categorized into three primary mechanism subclasses. The first subclass involves the acquisition of target mutations that lead to changes in the kinase domain, thereby hindering drug binding. The second mechanism, known as bypass resistance, entails tumor clones utilizing alternative signaling pathways for proliferation. Lastly, the third acquired mechanism pertains to histological transformation, such as the emergence of small cell lung cancer (SCLC) clones. The transformation of pathological types has brought great confusion to the clinical diagnosis and treatment process. We report a case of advanced lung adenocarcinoma with EGFR-sensitive mutation that transformed into small cell lung cancer after EGFR-TKIs treatment. Subsequent treatment revealed the presence of both adenocarcinoma and small cell carcinoma through needle biopsies at various metastatic sites. Based on the pathological, the patient received combination therapy with anlotinib at different times and achieved a long survival time.

A novel molecular classification for small cell lung cancer (SCLC) has been established utilizing the transcription factors achaete-scute homologue 1 (ASCL1), neurogenic differentiation factor 1 (NeuroD1), POU class 2 homeobox 3 (POU2F3), and yes-associated protein 1 (YAP1). This classification was predicated on the transcription factors. Conversely, there is a paucity of information regarding the distribution of these markers in other subtypes of pulmonary neuroendocrine tumors (PNET). Clinical and survival data for PNET patients were gathered from January 2008 to December 2020. Immunohistochemical analysis was employed to evaluate the expression. The relationship between YAP1 expression and outcomes in patients with pulmonary large cell neuroendocrine carcinoma (LCNEC) was examined. Data from low-grade PNET patients who had previously undergone immunotherapy were retrospectively gathered and analyzed. The ASCL1 positive rate was markedly elevated in SCLC (7.1% vs. 60%; P < 0.001) and LCNEC patients (7.1% vs. 38.5%; P = 0.034) compared to PC patients. The YAP1-positive rate was elevated in LCNEC compared to SCLC (43.6% vs. 20%, P = 0.028) and pulmonary carcinoid (PC) patients (43.6% vs. 21.4%; P = 0.021). The DLL3-positive rate in SCLC patients was greater than in SCLC and PC patients (37.1% vs. 23.1% vs. 0%; P = 0.028, P = 0.021). A significant level of tumor heterogeneity was noted, with SCLC and LCNEC patients exhibiting markedly higher heterogeneity than PC patients (65.7% vs. 56.3% vs. 21.4%; P = 0.005, P = 0.025). In patients with LCNEC, YAP1 positivity exhibited no correlation with PD-L1 expression (17.1% vs. 45.7%, P = 0.518). Tumor heterogeneity was also noted in transformed SCLC, with no significant differences in the expression levels of transcription factors between transformed and traditional SCLC. In 13 LCNEC patients with a history of ICI application, YAP1 exhibited no significant effect on PFS (P = 0.331) or OS (P = 0.17) in the subgroup analysis of LCNEC patients. Among the 14 patients with low-grade PNET who underwent immunotherapy, the disease control rate was 85.7%. Patients with high-grade PNET have high levels of expression of ASCL1 and DLL3, whereas patients with LCNEC have high levels of expression of YAP1. With regard to the transcription factor level, it was found that patients with SCLC and LCNEC had a much higher degree of tumor heterogeneity than those with PC. In patients with LCNEC who were receiving monotherapy of ICIs or chemotherapy in combination with ICIs, the expression of YAP1 did not appear to have any clear impact on the prognosis. This is due to the limited sample size of the study, which requires additional investigation. When compared to the expression of TFs in regular SCLC, the expression of TFs in converted SCLC is comparable.

Based on improvements in recurrence-free and overall survival, osimertinib is now widely used as an adjuvant treatment in stage II-IIIA non-small cell lung cancer (NSCLC) presenting with a common epithelial growth factor receptor (EGFR) mutation. Histological transformation is a well-known resistance mechanism to osimertinib in EGFR-mutated metastatic NSCLC, but we currently have insufficient data on recurrence mechanisms in the adjuvant context. We present here the case of a patient treated with adjuvant osimertinib and presenting a small cell lung cancer (SCLC) transformation as a recurrence.

A 54-year-old man, never-smoker and with no previous medical history, underwent right superior lobectomy with lymph node resection for a pT3N1M0 [stage IIIA, tumor-node-metastasis (TNM) 8th edition] adenocarcinoma. Programmed death-ligand 1 (PD-L1) negative with an EGFR exon 19 deletion. The patient received 4 cycles of adjuvant chemotherapy before starting adjuvant osimertinib 80 mg. After 35 months of adjuvant osimertinib the patient had a local recurrence and the re biopsy showed an SCLC transformation, underlining the importance of careful surveillance and biopsy at the time of recurrence in EGFR-mutated NSCLC.

this case report provides evidence of SCLC transformation while on adjuvant osimertinib, in a pT3N1 EGFR, RB1 and TP53-mutated pulmonary adenocarcinoma. This highlights the importance of biopsy on recurrence and the transformation potential of the EGFR, RB1 and TP53-mutated adenocarcinomas.

The lysine acetyltransferase 6A (KAT6A, MOZ, MYST3) is a member of the MYST family of protein acetyltransferases, which are essential for different biological processes such as craniofacial, embryonic, stem cell development, and hematopoiesis. KAT6A is an oncogene in human acute myeloid leukemia (AML), and KAT6A overexpression in AML is associated with metastases and poor prognoses. Furthermore, KAT6A mutations play an important role in cancer formation and progression and result in therapeutic resistance in both hematopoietic malignancies and solid tumors. In this review, we discuss the structural and biological functions of KAT6A and summarize the influence of KAT6A in the development of various tumors. In addition, the recent KAT6A/B inhibitors, their anticancer activities, challenges, and perspective of developing KAT6A/B inhibitors as anticancer drug candidates were introduced.

Patients with ALK-rearranged non-small cell lung cancer (NSCLC) who are treated with ALK tyrosine kinase inhibitors (ALK TKIs) have better prognoses. In this case report, we provide evidence of a novel ALK fusion, XPO1-ALK (intergenic), identified by next-generation DNA sequencing in a patient with advanced lung cancer. After 5 months of brigatinib targeted therapy, the patient clearly experienced tumor disintegration, and this treatment resulted in partial remission. To date, this patient has experienced 5 months of progression-free survival after brigatinib treatment. In addition to reporting the identification of a novel ALK fusion, XPO1-ALK (intergenic), and the sensitivity and safety of brigatinib treatment for lung cancer, this study increased the list of known ALK fusion partners in ALK-positive NSCLC. This case report has a significant clinical reference.

Macrophages are innate immune cells present in all tissues and play an important role in almost all aspects of the biology of living organisms. Extracellular vesicles (EVs) are released by cells and transport their contents (micro RNAs, mRNA, proteins, and long noncoding RNAs) to nearby or distant cells for cell-to-cell communication. Numerous studies have shown that macrophage-derived extracellular vesicles (M-EVs) and their contents play an important role in a variety of diseases and show great potential as biomarkers, therapeutics, and drug delivery vehicles for diseases. This article reviews the biological functions and mechanisms of M-EVs and their contents in chronic non-communicable diseases such as cardiovascular diseases, metabolic diseases, cancer, inflammatory diseases and bone-related diseases. In addition, the potential application of M-EVs as drug delivery systems for various diseases have been summarized.

Lung cancer is the leading cause of cancer-related deaths worldwide, highlighting a major clinical challenge. Lung cancer is broadly classified into two histologically distinct subtypes, termed small cell lung cancer (SCLC) or non-small cell lung cancer (NSCLC). Identification of various oncogenic drivers of NSCLC has facilitated the development of targeted therapies that have dramatically improved patient outcomes. However, acquired resistance to these targeted therapies is common, which ultimately results in patient relapse. Several on-target and off-target resistance mechanisms have been described for targeted therapies in NSCLC. One common off-target mechanism of resistance to these therapies is histological transformation of the initial NSCLC into SCLC, a highly aggressive form of lung cancer that exhibits neuroendocrine histology. This mechanism of resistance presents a significant clinical challenge, since there are very few treatments available for these relapsed patients. Although the phenomenon of NSCLC-to-SCLC transformation was described almost 20 years ago, only recently have we begun to understand the mechanisms underlying this therapy-driven response. These recent discoveries will be key to identifying novel biomarkers and therapeutic strategies to improve outcomes of patients that undergo NSCLC-to-SCLC transformation. Here, we highlight these recent advances and discuss the potential therapeutic strategies that they have uncovered to target this mechanism of resistance.

Non-Small Cell Lung Cancer (NSCLC) is a formidable global health challenge, responsible for the majority of cancer-related deaths worldwide. The Platelet-Derived Growth Factor Receptor (PDGFR) has emerged as a promising therapeutic target in NSCLC, given its crucial involvement in cell growth, proliferation, angiogenesis, and tumor progression. Among PDGFR inhibitors, avapritinib has garnered attention due to its selective activity against mutant forms of PDGFR, particularly PDGFRA D842V and KIT exon 17 D816V, linked to resistance against conventional tyrosine kinase inhibitors. In recent years, Machine Learning has emerged as a powerful tool in pharmaceutical research, offering data-driven insights and accelerating lead identification for drug discovery. In this research article, we focus on the application of Machine Learning, alongside the RDKit toolkit, to identify potential anti-cancer drug candidates targeting PDGFR in NSCLC. Our study demonstrates how smart algorithms efficiently narrow down large screening collections to target-specific sets of just a few hundred small molecules, streamlining the hit discovery process. Employing a Machine Learning-assisted virtual screening strategy, we successfully preselected 220 compounds with potential PDGFRA inhibitory activity from a vast library of 1.048 million compounds, representing a mere 0.013% of the original library. To validate these candidates, we employed traditional genetic algorithm-based virtual screening and docking methods. Remarkably, we found that ZINC000002931631 exhibited comparable or even superior inhibitory potential against PDGFRA compared to Avapritinib, which highlights the value of our Machine Learning approach. Moreover, as part of our lead validation studies, we conducted molecular dynamic simulations, revealing critical molecular-level interactions responsible for the conformational changes in PDGFRA necessary for substrate binding. Our study exemplifies the potential of Machine Learning in the drug discovery process, providing a more efficient and cost-effective means of identifying promising drug candidates for NSCLC treatment. The success of this approach in preselecting compounds with potent PDGFRA inhibitory potential highlights its significance in advancing personalized and targeted therapies for cancer treatment.

Small cell lung cancer (SCLC) is highly aggressive with poor prognosis. Despite a relative prevalence of circulating tumour DNA (ctDNA) in SCLC, liquid biopsies are not currently implemented, unlike non-SCLC where cell-free DNA (cfDNA) mutation profiling in the blood has utility for guiding targeted therapies and assessing minimal residual disease. cfDNA methylation profiling is highly sensitive for SCLC detection and holds promise for disease monitoring and molecular subtyping; cfDNA fragmentation profiling has also demonstrated clinical potential. Extrachromosomal DNA (ecDNA), that is often observed in SCLC, promotes tumour heterogeneity and chemotherapy resistance and can be detected in blood. We discuss how these cfDNA profiling modalities can be harnessed to expand the clinical applications of liquid biopsy in SCLC.

The aim of this study was to establish an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the detection of osimertinib in rat plasma, lung and brain tissues.

Forty-eight rats were randomly divided into an experimental group (receiving osimertinib at doses of 5, 8, and 10 mg/kg) and a control group. After continuous intragastric administration for 15 days, samples of blood, lung, and brain tissue were collected. Chromatographic separation was achieved using a BEH C18 column with gradient elution, employing a mobile phase of water (containing 0.1% (v/v) formic acid) and acetonitrile. The concentration of osimertinib in the samples was determined using an AB SCIEX 5500 triple quadrupole mass spectrometer operated in positive electrospray ionization (ESI+) and multiple reaction monitoring (MRM) mode.

A UPLC-MS/MS analytical method for determining osimertinib concentrations was successfully established and validated. A linear relationship was observed for osimertinib concentrations in plasma within the range of 1-300 ng/mL, and in lung and brain tissues within the range of 0.5-50 ng/mL. The selectivity, accuracy, precision, matrix effect, extraction recovery, and stability all meet the requirements of methodological validation criteria.

A rapid and sensitive UPLC-MS/MS method was developed and validated for quantifying osimertinib concentrations in rat plasma, lung, and brain tissues, providing a valuable tool for pharmacokinetic and tissue distribution studies.

Secretory carcinoma is a rare breast tumor driven by ETV6::NTRK3 fusion. It has characteristic morphologic features and identification of these tumors is critical as these patients may benefit from TRK inhibitors. Morphologic shift upon treatment has not been reported in secretory carcinoma or other NTRK-driven tumors. Herein we describe a patient with secretory carcinoma showing transdifferentiation into metaplastic carcinoma (spindle cell and squamous cell carcinoma) at the metastatic site following treatment. Identification of these morphologic shifts is crucial for accurate classification and identification of potential resistant mechanisms.

Non-small cell lung cancer (NSCLC) is a type of lung cancer, the incidence and mortality rate have been high, and the use of monotherapy is easy to make patients develop tolerance. Atmospheric pressure plasma (APP) is an emerging technology for killing cancer cells in recent years, and combination of berberine (BBR) mechanism has not been fully elucidated for NSCLC. The article's primary goal is to investigate the effect of combination on NSCLC and its associated characterization.

Antiproliferative effects were detected by cell viability assay and colony formation, and flow cytometry analysis of apoptosis and cycling showed that the combination synergistically induced apoptosis. Then, extracellular reactive oxygen species (ROS)levels and DCFH-DA-based kits examined intracellular ROS levels, and their effects on mitochondrial membrane potential were measured. Study reveals that co-induced apoptosis is associated with ROS accumulation. Subsequently, Western blotting (WB) detected the expression of epidermal growth factor receptor (EGFR), and the important signaling pathway proteins Ras/ERK and AKT/mTOR. Results showed that it could downregulation of EGFR protein expression and inhibit of activation of ERK/AKT signaling pathways. Simultaneous wound healing assay and epithelial-to-mesenchymal transition (EMT) marker detection were performed for the assessment of migration and EMT ability of NSCLC cells. Combination therapy inhibited migration and EMT of NSCLC cells.

The results of this study show that the combination can synergistically induce apoptosis of NSCLC by regulating ROS production. EGFR downregulation and AKT/ERK signaling pathway inhibition are linked to the synergistic effect.

Lung cancer, a prevalent and deadly malignancy, is classified into small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). SCLC is further subdivided into four molecular subtypes-SCLC-A, SCLC-N, SCLC-P, and SCLC-I-based on key transcription factor expression.

Immunohistochemistry (IHC) was used to assess ASCL1, NEUROD1, and POU2F3 expression in tumor tissues. The H-Score quantified these results. Clinical characteristics, overall survival (OS), progression-free survival (PFS), and treatment responses were analyzed by subtype, and sensitivity to different treatments was assessed. Risk factors were identified through univariate and multivariate analyses.

IHC and H-Score analysis showed that POU2F3 expression was mutually exclusive with ASCL1 or NEUROD1. Subtype distribution was as follows: SCLC-A (40 %), SCLC-N (33 %), SCLC-P (7 %), and SCLC-I (20 %). There were no significant differences in baseline characteristics, OS (p = 0.829), or PFS (p = 0.924) among subtypes. However, the SCLC-I subtype showed a trend toward improved outcomes with platinum-based doublet chemotherapy plus immune checkpoint inhibitors. Multivariate COX regression identified M stage (HR: 1.72, 95 % CI: 1.13-2.63, p = 0.012) and bone metastasis at diagnosis (HR: 1.58, 95 % CI: 1.02-2.43, p = 0.040) as independent risk factors.

This study confirmed the SCLC subtyping based on key transcription factors. While no significant differences in OS and PFS among subtypes were found, the SCLC-I subtype showed potential benefit from platinum-based chemotherapy combined with immune checkpoint inhibitors. M stage and bone metastasis at diagnosis were identified as independent risk factors for SCLC.

Although adeno-to-squamous transition (AST) has been observed in association with resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) in clinic, its causality, molecular mechanism and overcoming strategies remain largely unclear. We here demonstrate that squamous transition occurs concomitantly with TKI resistance in PC9-derived xenograft tumors. Perturbation of squamous transition via DNp63 overexpression or knockdown leads to significant changes in TKI responses, indicative of a direct causal link between squamous transition and TKI resistance. Integrative RNA-seq, ATAC-seq analyses and functional studies reveal that FOXA1 plays an important role in maintaining adenomatous lineage and contributes to TKI sensitivity. FOXM1 overexpression together with FOXA1 knockout fully recapitulates squamous transition and TKI resistance in both PC9 xenografts and patient-derived xenograft (PDX) models. Importantly, pharmacological inhibition of RAPGEF3 combined with EGFR TKI efficiently overcomes TKI resistance, especially in RAPGEF3high PDXs. Our findings provide novel mechanistic insights into squamous transition and therapeutic strategy to overcome EGFR TKI resistance in lung cancer.

APOBEC mutagenesis is one of the most common endogenous sources of mutations in human cancer and is a major source of genetic intratumor heterogeneity. High levels of APOBEC mutagenesis are associated with poor prognosis and aggressive disease across diverse cancers, but the mechanistic and functional impacts of APOBEC mutagenesis on tumor evolution and therapy resistance remain relatively unexplored. To address this, we investigated the contribution of APOBEC mutagenesis to acquired therapy resistance in a model of EGFR-mutant non-small cell lung cancer. We find that inhibition of EGFR in lung cancer cells leads to a rapid and pronounced induction of APOBEC3 expression and activity. Functionally, APOBEC expression promotes the survival of drug-tolerant persister cells (DTPs) following EGFR inhibition. Constitutive expression of APOBEC3B alters the evolutionary trajectory of acquired resistance to the EGFR inhibitor gefitinib, making it more likely that resistance arises through de novo acquisition of the T790M gatekeeper mutation and squamous transdifferentiation during the DTP state. APOBEC3B expression is associated with increased expression of the squamous cell transcription factor ΔNp63 and squamous cell transdifferentiation in gefitinib-resistant cells. Knockout of p63 in gefitinib-resistant cells reduces the expression of the ΔNp63 target genes IL1α/β and sensitizes these cells to the third-generation EGFR inhibitor osimertinib. These results suggest that APOBEC activity promotes acquired resistance by facilitating evolution and transdifferentiation in DTPs, and suggest that approaches to target ΔNp63 in gefitinib-resistant lung cancers may have therapeutic benefit.

Histological transformation from lung adenocarcinoma (ADC) to small cell lung carcinoma (SCLC), large cell neuroendocrine carcinoma (LCNEC), squamous cell carcinoma (SCC), and sarcomatoid carcinoma (PSC) after targeted therapies is recognized as a mechanism of resistance in ADC treatments. Patients with transformed lung cancer typically experience a poor prognosis and short survival time. However, effective treatment options for these patients are currently lacking. Therefore, understanding the mechanisms underlying histological transformation is crucial for the development of effective therapies. Hypotheses including intratumoral heterogeneity, cancer stem cells, and alteration of suppressor genes have been proposed to explain the mechanism of histological transformation. In this review, we provide a comprehensive overview of the known molecular features and signaling pathways of transformed tumors, and summarized potential therapies based on previous findings.

Immunotherapy targeting immune checkpoints (ICPs), such as programmed death-ligand-1 (PD-L1), is used as a treatment option for advanced or metastatic non-small cell lung cancer (NSCLC). However, overall response rate to anti-PD-L1 treatment is limited due to antigen heterogeneity and the immune-suppressive tumor microenvironment. Human leukocyte antigen-G (HLA-G), an ICP as well as a neoexpressed tumor-associated antigen, is previously demonstrated to be a beneficial target in combination with anti-PD-L1. In this study, a nanobody-based trispecific T cell engager (Nb-TriTE) is developed, capable of simultaneously binding to T cells, macrophages, and cancer cells while redirecting T cells toward tumor cells expressing PD-L1- and/or HLA-G. Nb-TriTE shows broad spectrum anti-tumor effects in vitro by augmenting cytotoxicity mediated by human peripheral blood mononuclear cells (PBMCs). In a humanized immunodeficient murine NSCLC model, Nb-TriTE exhibits superior anti-cancer potency compared to monoclonal antibodies and bispecific T cell engagers. Nb-TriTE, at the dose with pharmacoactivity, does not induce additional enhancement of circulating cytokines secretion from PMBCs. Nb-TriTE effectively prolongs the survival of mice without obvious adverse events. In conclusion, this study introduces an innovative therapeutic approach to address the challenges of immunotherapy and the tumor microenvironment in NSCLC through utilizing the dual ICP-targeting Nb-TriTE.

BRAF activating mutations occur in approximately 10% of metastatic colorectal cancer (CRCs) and are associated with worse prognosis due to an inferior response to standard chemotherapy. Standard of care for patients with refractory metastatic BRAF V600E CRC is treatment with BRAF and EGFR inhibitors. However, responses are not durable. Lineage plasticity to neuroendocrine cancer is an emerging mechanism of targeted therapy resistance in several cancer types. Enteroendocrine cells (EECs), the neuroendocrine cell of the intestine, are uniquely present in BRAF V600E CRC as compared to BRAF wildtype CRC. Here, we demonstrated that combined BRAF and EGFR inhibition enriches for EECs in several models of BRAF V600E CRC. Additionally, EECs and other secretory cell types were enriched in a subset of BRAF V600E CRC patient samples following targeted therapy. Importantly, inhibition of the lysine demethylase LSD1 with a clinically relevant inhibitor attenuated targeted therapy-induced EEC enrichment through blocking the interaction of LSD1, CoREST2 and STAT3.

Our findings that BRAF plus EGFR inhibition induces lineage plasticity in BRAF V600E CRC represents a new paradigm for how resistance to BRAF plus EGFR inhibition occurs and our finding that LSD1 inhibition blocks lineage plasticity has the potential to improve responses to BRAF plus EGFR inhibitor therapy in patients.

Chemotherapy agents for lung cancer often cause apoptotic resistance in cells, leading to suboptimal therapeutic outcomes. FIN56 can be a potential treatment for lung cancer as it induces non-apoptotic cell death, namely ferroptosis. However, a bottleneck exists in FIN56-induced ferroptosis treatment; specifically, FIN56 fails to induce sufficient oxidative stress and may even trigger the defense system against ferroptosis, resulting in poor therapeutic efficacy. To overcome this, this study proposed a strategy of co-delivering FIN56 and piperlongumine to enhance the ferroptosis treatment effect by increasing oxidative stress and connecting with the autophagy pathway. FIN56 and piperlongumine were encapsulated into silk fibroin-based nano-disruptors, named FP@SFN. Characterization results showed that the particle size of FP@SFN was in the nanometer range and the distribution was uniform. Both in vivo and in vitro studies demonstrated that FP@SFN could effectively eliminate A549 cells and inhibit subcutaneous lung cancer tumors. Notably, ferroptosis and autophagy were identified as the main cell death pathways through which the nano-disruptors increased oxidative stress and facilitated cell membrane rupture. In conclusion, nano-disruptors can effectively enhance the therapeutic effect of ferroptosis treatment for lung cancer through the ferroptosis-autophagy synergy mechanism, providing a reference for the development of related therapeutics.

The diagnosis and treatment of head and neck undifferentiated carcinoma (HNUC) present significant challenges. Herein, we present the case of a patient with advanced HNUC who underwent conversion surgery following treatment with a combination of pembrolizumab and nimotuzumab. During therapy, histological transformation from undifferentiated to sarcomatoid carcinoma was detected at the primary site. This case not only highlights the potential of immune combination-targeted therapy to reduce tumour burden and increase the surgical options for patients, but also reveals the complex alterations in tumour biology that may occur during treatment. It emphasizes the necessity for routine pathological assessments throughout the therapeutic regimen to guide personalised therapeutic strategies and optimise patient prognoses.

Lung cancer is one of the major cancer types and poses challenges in its treatment, including lack of specificity and harm to healthy cells. Nanoparticle-based drug delivery systems (NDDSs) show promise in overcoming these challenges. While conventional NDDSs have drawbacks, such as immune response and capture by the reticuloendothelial system (RES), extracellular vesicles (EVs) present a potential solution. EVs, which are naturally released from cells, can evade the RES without surface modification and with minimal toxicity to healthy cells. This makes them a promising candidate for developing a lung-cancer-targeting drug delivery system. EVs isolated from vascular endothelial cells, such as human umbilical endothelial-cell-derived EVs (HUVEC-EVs), have shown anti-angiogenic activity in a lung cancer mouse model; therefore, in this study, HUVEC-EVs were chosen as a carrier for drug delivery. To achieve lung-cancer-specific targeting, HUVEC-EVs were engineered to be decorated with GE11 peptides (GE11-HUVEC-EVs) via a postinsertional technique to target the epidermal growth factor receptor (EGFR) that is overexpressed on the surface of lung cancer cells. The GE11-HUVEC-EVs were loaded with vinorelbine (GE11-HUVEC-EVs-Vin), and then characterized and evaluated in in vitro and in vivo lung cancer models. Further, we examined the binding affinity of ABCB1, encoding P-glycoprotein, which plays a crucial role in chemoresistance via the efflux of the drug. Our results indicate that GE11-HUVEC-EVs-Vin effectively showed tumoricidal effects against cell and mouse models of lung cancer.

Histologic transformation from EGFR-mutant non-small cell lung cancer (NSCLC) to small-cell lung cancer (SCLC) is a key mechanism of resistance to EGFR tyrosine kinase inhibitors (TKI). However, transcriptomic changes between NSCLC and transformed SCLC (t-SCLC) remain unexplored.

We conducted whole-transcriptome analysis of 59 regions of interest through the spatial profiling of formalin-fixed, paraffin-embedded tissues obtained from 10 patients (lung adenocarcinoma, 22; combined SCLC/NSCLC, 7; and t-SCLC, 30 regions of interests). Transcriptomic profiles and differentially expressed genes were compared between pre- and post-transformed tumors.

Following EGFR-TKI treatment, 93.7% (15/16) of t-SCLC components evolved into neuroendocrine-high subtypes (SCLC-A or SCLC-N). The transition to t-SCLC occurred regardless of EGFR-TKI treatment and EGFR mutational status, with a notable decrease in EGFR expression (P < 0.001) at both mRNA and protein levels. Pathway analysis revealed that gene overexpression was related to epigenetic alterations in t-SCLC. Interestingly, histone deacetylase inhibitors restored EGFR expression in SNU-2962A cells and their organoid model. The synergistic effects of third-generation EGFR-TKI osimertinib and the histone deacetylase inhibitor fimepinostat were validated in both in vitro and in vivo models.

Our study demonstrated that most t-SCLC cases showed neuronal subtypes with low EGFR expression. Differentially expressed gene analysis and t-SCLC preclinical models identified an epigenetic modifier as a promising treatment strategy for t-SCLC.

Background: Circular RNAs (circ-RNAs) have been demonstrated to influence initiation, drug resistance, and metastasis of tumors. However, the effects of circular-phosphoglycerate mutase 1 (circ-PGAM1) on matrine resistance in nonsmall cell lung cancer (NSCLC) remain unknown. Materials and Methods: The reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to determine gene expression. The terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and cell colony formation assays were used to evaluate NSCLC apoptosis and cell proliferation after indicated treatments, respectively. Results: circ-PGAM1 was upregulated in human NSCLC cell lines (H1299 and A549) compared with the human normal lung epithelial (BEAS-2B) cells. circ-PGAM1 overexpression reversed the matrine treatment-induced inhibition on proliferation of NSCLC cells (A549 and H1299) and rescued the matrine treatment-stimulated apoptosis of these cells. miR-326 was demonstrated to interact with circ-PGAM1. circ-PGAM1 knockdown enhanced the antitumor effect of matrine on NSCLC cell proliferation and apoptosis, which was reversed by miR-326 inhibition. The authors also identified CXCR5 as a key downstream target of miR-326 in A549 cells. Conclusions: circ-PGAM1 enhances matrine resistance of NSCLC cells through the miR-326/CXCR5 axis. The authors' findings provide new insights into NSCLC-targeted therapy.

Lung adenocarcinoma (LUAD) generally presents as an immunosuppressive microenvironment. The characteristics of cell-to-cell communication in the LUAD microenvironment has been unclear. In this study, the LUAD bulk RNA-seq data and single-cell RNA-seq data were retrieved from public dataset. Differential expression genes (DEGs) between LUAD tumor and adjacent non-tumor tissues were calculated by limma algorithm, and then detected by PPI, KEGG, and GO analysis. Cell-cell interactions were explored using the single-cell RNA-seq data. Finally, the first 15 CytoHubba genes were used to establish related pathways and these pathways were used to characterize the immune-related ligands and their receptors in LUAD. Our analyses showed that monocytes or macrophages interact with tissue stem cells and NK cells via SPP1 signaling pathway and tissue stem cells interact with T and B cells via CXCL signaling pathway in different states. Hub genes of SPP1 participated in SPP1 signaling pathway, which was negatively correlated with CD4+ T cell and CD8+ T cell. The expression of SPP1 in LUAD tumor tissues was negatively correlated with the prognosis. While CXCL12 participated in CXCL signaling pathway, which was positively correlated with CD4+ T cell and CD8+ T cell. The role of CXCL12 in LUAD tumor tissues exhibits an opposite effect to that of SPP1. This study reveals that tumor-associated monocytes or macrophages may affect tumor progression. Moreover, the SPP1 and CXCL12 may be the critic genes of cell-to-cell communication in LUAD, and targeting these pathways may provide a new molecular mechanism for the treatment of LUAD.