This review discusses the critical roles of Ataxia Telangiectasia Mutated Kinase (ATM), ATM and Rad3-related Kinase (ATR), and DNA-dependent protein kinase (DNA-PK) in the DNA damage response (DDR) and their implications in cancer. Emphasis is placed on the intricate interplay between these kinases, highlighting their collaborative and distinct roles in maintaining genomic integrity and promoting tumour development under dysregulated conditions. Furthermore, the review covers ongoing clinical trials, patent literature, and medicinal chemistry campaigns on ATM/ATR/DNA-PK inhibitors as antitumor agents. Notably, the medicinal chemistry campaigns employed robust drug design strategies and aimed at assembling new structural templates with amplified DDR kinase inhibitory ability, as well as outwitting the pharmacokinetic liabilities of the existing DDR kinase inhibitors. Given the success attained through such endeavours, the clinical pipeline of DNA repair kinase inhibitors is anticipated to be supplemented by a reasonable number of tractable entries (DDR kinase inhibitors) soon.

Osteosarcoma (OS), frequently observed in children and adolescents, is one of the most common primary malignant tumors of the bone known to be associated with a high capacity for invasion and metastasis. The incidence of osteosarcoma in children and adolescents is growing annually, although improvements in survival remain limited. With the clinical application of neoadjuvant chemotherapy, chemotherapy combined with limb-preserving surgery has gained momentum as a major intervention. However, certain patients with OS experience treatment failure owing to chemoradiotherapy resistance or metastasis. Nuclear factor E2-related factor 2 (Nrf2), a key antioxidant factor in organisms, plays a crucial role in maintaining cellular physiological homeostasis; however, its overactivation in cancer cells restricts reactive oxygen species production, promotes DNA repair and drug efflux, and ultimately leads to chemoradiotherapy resistance. Recent studies have also identified the functions of Nrf2 beyond its antioxidative function, including the promotion of proliferation, metastasis, and regulation of metabolism. The current review describes the multiple mechanisms of chemoradiotherapy resistance in OS and the substantial role of Nrf2 in the signaling regulatory network to elucidate the function of Nrf2 in promoting OS chemoradiotherapy resistance and formulating relevant therapeutic strategies.

A method to directly predict the number of nucleic acid bases in a single-stranded DNA (ssDNA) or a genomic DNA has been proposed with a combination of Raman spectroscopy and an Artificial Neural Network (ANN) algorithm. In this work, the algorithm was trained by using the Raman spectroscopic signatures from a cohort of 32 ssDNAs. The algorithm could predict the number of bases in an unknown sequence with an R2 value of more than 0.83. Chemical mutation using the hydroxylamine method was performed on a ssDNA and also a genomic herring sperm DNA, and the extent was monitored using optical absorbance measurements. The mutation of bases, such as cytosine, can introduce subtle alterations in the DNA structure, potentially leading to significant biological consequences, including neurodegenerative and epigenetic disorders. Also, during the mutation process, the unstable intermediate can undergo further transformation, converting bases such as cytosine to uracil, thus significantly altering the base-pairing properties of the DNA. A one-to-one correspondence was observed between the experimentally and computationally predicted mutated bases in both the single- and double-stranded DNA (dsDNA), thus opening up avenues for the detection of mutations in a diagnostic setup.

The interaction between metals and catecholamines plays a pivotal role in the generation of reactive oxygen species (ROS), leading to oxidative stress and DNA damage. ROS are linked to several diseases, including neurodegenerative disorders such as Parkinson's and Alzheimer's diseases. This review examines how essential metals (iron, copper, zinc, manganese) and a few non-essential metal(loid)s (mercury, chromium, arsenic, aluminum, cadmium, and nickel) contribute to oxidative stress in the presence of catecholamines. In the presence of metals, catecholamines can cause oxidative DNA modification, possibly resulting in cell apoptosis, by taking part in redox reactions and oxidizing to the corresponding aminochrome with simultaneous ROS production. Essential metals are vital for physiological functions, but imbalances in their homeostasis can be harmful. Furthermore, non-essential metals, commonly encountered through environmental or occupational exposure, can exhibit significant toxicity. Previous studies on catecholamine-induced oxidative stress focused on copper and iron, but this review emphasizes the need to investigate other neurotoxic metals and expand existing knowledge on the interactions between metals, catecholamines, and DNA damage. Results from such research could help prioritizing the development of new assessment methods associated with adverse outcome pathways, to reliably predict harmful effects on human health, aiding in the development of therapeutical strategies. The present work will help to shed light on the interplay of metals, catecholamines, and DNA damage in different diseases hopefully fostering new research in this still understudied topic. Future research should investigate the molecular mechanisms through which these metals affect neuronal health and contribute to disease pathogenesis.

Numerous long noncoding RNAs (lncRNAs) are generated in response to external stimuli, but the scope and functions of such activity are not known. Here, this study provides insight into how the transcription of lncRNAs is connected to DNA damage response by identifying the lncRNA ZFAS1, which is required for cell cycle arrest, transcription regulation, and DNA repair. Mechanistically, ZFAS1 facilitates dynamic changes in hyperphosphorylated forms of the large subunit of RNA polymerase II (RNAPII) around transcription initiation sites by directly targeting the regulated genes. It is shown that extensive transcription shutdown and concomitant stimulated engagement of RNAPII-Ser2P are crucial for repair and cell survival upon genotoxic stress. Finally, ZFAS1 knockout in mice dampened nucleotide excision repair (NER) and led to kidney dysplasia. Overall, the findings extend the understanding of lncRNAs in DNA damage repair (DDR) and imply a protective role of lncRNA against DDR-deficient developmental disorders.

Isoniazid and rifampicin, frontline tuberculosis drugs, frequently induce drug-induced liver injury (DILI), marked by hepatitis and hepatocyte necrosis. Polysaccharides from Dicliptera chinensis (L.) Juss. (DCP) exhibit anti-inflammatory, antioxidant, and hepatoprotective properties, but their effects on DILI remain unexplored OBJECTIVE: This study investigated DCP therapeutic potential against DILI and elucidated its molecular mechanisms METHODS: In vivo (using C57BL/6 mice) and in vitro (using HepG2 cells) DILI models were established and treated with DCP. Transcriptomics, qRT-PCR, and Western blotting were employed to analyze pathway regulation RESULTS: DCP significantly attenuated hepatocyte apoptosis, inflammation, and oxidative stress in DILI mice. Transcriptomic analysis linked DCP'S effects to the modulation of AMPK-FOXO3, p53, and NF-κB pathways, alongside regulation of antioxidant and cell cycle genes. In HepG2 cells, DCP similarly protected against DILI by enhancing AMPK phosphorylation, which facilitated the FOXO3 nuclear translocation. Both models demonstrated DCP'S suppression of p53 and NF-κB activation, restoration of antioxidant defenses, and correction of cell cycle dysregulation CONCLUSION: DCP mitigates DILI by reducing apoptosis, oxidative stress, and inflammation through activation of the AMPK-FOXO3 pathway, inhibition of p53/NF-κB signaling, and stabilization of the cell cycle. These findings highlight DCP'S potential as a therapeutic agent for DILI prevention and treatment.

DNA damage repair (DDR) is essential for cancer cell survival and treatment resistance, making it a critical target for tumor therapy. The eukaryotic AAA+ adenosine triphosphatase valosin-containing protein (VCP), which is transported from the cytoplasm into the nucleus, plays a critical role in the DDR process. However, the nuclear translocation and molecular mechanism of VCP for DDR remain elusive. Here, we define VCP as a KPNB1 interacting protein through a combination of chemical and immunoprecipitation mass spectrometry approaches. Further biochemical studies elucidate that KPNB1 directly transports VCP into the nucleus. We also identify withaferin A (WA) as a small molecule that can retard VCP nuclear localization via covalent binding to CYS 158 of KPNB1. Further studies verify WA as an effective antitumor drug candidate via blocking VCP nuclear localization to impact on the DDR pathway in vivo. Our findings underly the unclear VCP's role in DDR in a KPNB1-dependent manner and provide an important theoretical basis for developing small-molecule inhibitors targeting this process.

Elevated cancer risk and compromised reproductive health have been well documented in flight attendants (FA), but the etiology remains unknown. Many studies using cell and animal models suggest that air travel related exposures might plausibly explain the adverse health outcomes observed in flight crew, but our understanding of the underlying biological mechanisms is incomplete. During air travel, FA are constantly exposed to complex mixtures of mutagens in the flight cabin that may contribute to genomic instability by inducing DNA damage and interfering with DNA repair. Defects in DNA repair capacity (DRC) have been associated with risk of cancer and other diseases. To explore our hypothesis that alterations in DNA damage and repair in FA are related to flight travel, we conducted a pilot study of FA's DNA damage and assess global DNA repair efficiency pre and post flight. We collected venous blood samples from nine FA before and after flight. Differential blood cell counts were carried out to assess immune responses and functional assays were performed to assess the DNA damage response. The CometChip assay was employed to quantify baseline DNA damage and repair kinetics for DNA damage induced by X-rays. Fluorescence multiplex based host cell reactivation (FM-HCR) assays were utilized to assess DRC in five major DNA repair pathways. Our findings revealed a significant increase in lymphocyte counts as well as diminished repair of ionizing radiation induced DNA damage and excision of 8oxoG:C lesions in after flight samples. Our results illustrate the potential for using biological samples to identify molecular mechanisms that may implicate impaired genomic stability and altered immune responses in the etiology of excess cancer in FAs.

Currently, advanced RT techniques such as VMAT and HT are being developed to optimize tumor coverage while minimizing radiation exposure to the surrounding organs that are at risk. Despite their growing clinical use, comparative studies evaluating the dosimetric and radiobiological effects of these modalities remain limited. In this study, A549, HeLa, and HepG2 cells were exposed to a single 2 Gy dose, using three RT techniques (3D-CRT, dual arc VMAT, and HT). Treatment plans were generated using a water phantom to ensure consistent target coverage and comparable dosimetric parameters across the techniques. Multiple radiobiological endpoints were assessed to evaluate the cellular responses. Although all three techniques yielded similar dosimetric parameters without statistically significant differences, the biological responses varied among the cell lines. Notably, VMAT and HT demonstrated superior tumor cell suppression compared to 3D-CRT. This was likely due to their enhanced dose conformity and modulation precision, which potentially led to improved tumor cell killing. These findings highlight the importance of integrating radiobiological assessments with physical dose metrics to inform the clinical application of advanced RT technologies. However, this study had several limitations. The use of a single radiation dose limited its clinical relevance, and the immediate post-irradiation assessments may not have captured delayed biological responses. Additionally, the small number of replicates may have reduced the study's statistical power. Future studies incorporating dose fractionation schemes, time course analyses, and larger sample sizes are warranted to better simulate clinical conditions and further elucidate the radiobiological effects of advanced RT techniques.

Maintenance of genome integrity is paramount to molecular programs in multicellular organisms. Throughout the lifespan, various endogenous and environmental factors pose persistent threats to the genome, which can result in DNA damage. Understanding the functional consequences of DNA damage requires investigating their preferred genomic distributions and influences on gene regulatory programs. However, such analysis is hindered by both the complex cell-type compositions within organs and the high background levels due to the stochasticity of damage formation. To address these challenges, we developed Paired-Damage-seq for joint analysis of oxidative and single-stranded DNA damage with gene expression in single cells. We applied this approach to cultured HeLa cells and the mouse brain as a proof of concept. Our results indicated the associations between damage formation and epigenetic changes. The distribution of oxidative DNA damage hotspots exhibits cell-type-specific patterns; this selective genome vulnerability, in turn, can predict cell types and dysregulated molecular programs that contribute to disease risks.

The DNA base-excision repair (BER) pathway shares the second part of its enzymatic chain with the single-strand break (SSB) repair pathway. BER is initiated by a glycosylase, such as UDG, while SSBR is initiated by the multifunctional enzyme PARP1. The very early steps in the identification of the DNA damage are crucial to the correct initiation of the repair chains, and become even more complex when considering the realistic environment of damage to the DNA in the nucleosome. We performed molecular dynamics computer simulations of the interaction between the glycosylase UDG and a mutated uracil (as could result from oxidative deamination of cytosine), and between the Zn1-Zn2 fragment of PARP1 and a simulated SSB. The model system is a whole nucleosome in which DNA damage is inserted at various typical positions along the 145-bp sequence. It is shown that damage recognition by the enzymes requires very strict conditions, unlikely to be matched by pure random search along the DNA. We propose that mechanical deformation of the DNA around the defective sites may help signaling the presence of the defect, accelerating the search process.

Ovarian cancer (OC) is the most lethal malignancy in the female reproductive system, and chemotherapy drug resistance is the main cause of treatment failure. The Mitogen-Activated Protein Kinases (MAPK) pathway plays a pivotal role in regulating cell proliferation, migration, and invasive capacity in response to extracellular stimuli. This review focuses on the mechanisms and therapeutic strategies related to the JNK/p38 MAPK signaling pathway in OC resistance. The JNK/p38 MAPK pathway plays a dual role in OC chemoresistance. This review examines its role in mediating OC treatment resistance by exploring the mechanisms of action of the JNK/p38 MAPK signaling pathway, particularly its involvement in several key biological processes, including apoptosis, autophagy, DNA damage response, the tumor microenvironment (TME), and drug efflux. Additionally, the review investigates the timing of activation of this pathway and its crosstalk with other signaling pathways such as PI3K/AKT and NF-κB. Targeting JNK/p38 MAPK signaling has shown promise in reversing chemoresistance, with several inhibitors and natural compounds demonstrating potential in preclinical studies. Regulating JNK/p38 MAPK may transform what was once a terminal obstacle into a manageable challenge for OC patients with chemotherapy resistance, ultimately improving survival and quality of life.

REV7, also named MAD2B or MAD2L2, is a subunit of the DNA translesion polymerase zeta and also part of the 53BP1-shieldin complex, which is present at sites of DNA double-strand breaks. REV7 has high sequence similarity to the MAD2 spindle assembly checkpoint protein, prompting us to examine whether REV7 has a checkpoint function. We observed that, in chicken and human cells exposed to agents that induce DNA replication stress, REV7 inhibits mitotic entry; this effect is most evident when the canonical DNA replication stress checkpoint, mediated by ATR, is inhibited. Similar to MAD2, REV7 undergoes conformational changes upon ligand binding, and its checkpoint function depends on its ability to homodimerize and bind its ligands. Notably, even in unchallenged cells, deletion of the REV7 gene leads to premature mitotic entry, raising the possibility that the REV7 checkpoint monitors ongoing DNA replication.

Cancer immunotherapy, alongside surgery, radiation therapy, and chemotherapy, has emerged as a key treatment modality. Immune checkpoint inhibitors (ICIs) represent a promising immunotherapy that plays a critical role in the management of various solid tumors. However, the limited efficacy of ICI monotherapy and the development of primary or secondary resistance to combination therapy remain a challenge. Consequently, identifying molecular markers for predicting ICI efficacy has become an area of active clinical research. Notably, the correlation between DNA damage repair (DDR) mechanisms and the effectiveness of ICI treatment has been established. This review outlines the two primary pathways of DDR, namely, the homologous recombination repair pathway and the mismatch repair pathway. The relationship between these key genes and ICIs has been discussed and the potential of these genes as molecular markers for predicting ICI efficacy summarized.

High-grade serous ovarian carcinoma (HGSOC) is the most aggressive subtype of epithelial ovarian cancer and a leading cause of mortality among gynecologic malignancies. This review aims to comprehensively analyze the morphological, immunohistochemical, and molecular features of HGSOC, highlighting its pathogenesis and identifying biomarkers with diagnostic, prognostic, and therapeutic significance. Special emphasis is placed on the role of tumor microenvironment (TME) and genomic instability in shaping the tumor's behavior and therapeutic vulnerabilities. Key advancements, such as the identification of TP53 and BRCA mutations, the classification of homologous recombination repair (HRR) deficiencies, and the clinical implications of biomarkers like folate receptor alpha (FRα) and PD-L1 are discussed. These findings reveal actionable insights into targeted therapies, including immune checkpoint inhibitors and PARP inhibitors, which hold promise for improving outcomes in HGSOC. This synthesis of knowledge aims to bridge gaps in understanding HGSOC's multifaceted biology, enhance clinical decision-making, and foster the development of precision therapies.

The role of MUTYH, a DNA repair glycosylase in the pathogenesis of acute kidney injury (AKI) is unclear. In this study, it is found that MUTYH protein levels are significantly decreased in the kidneys of cisplatin- or folic acid (FA)-induced mouse AKI models and patients with AKI. MUTYH deficiency aggravates renal dysfunction and tubular injury following cisplatin and FA treatment, along with the accumulation of 7, 8-dihydro-8-oxoguanine (8-oxoG) and impairs mitochondrial function. Importantly, the overexpression of type 2 MUTYH (nuclear) significantly ameliorates cisplatin-induced apoptosis, oxidative stress, mitochondrial dysfunction, and DNA damage in vivo and in vitro. In contrast, overexpression of type 1 MUTYH (mitochondrial) shows a marginal effect against cisplatin-induced injury, indicating the chief role of type 2 MUTYH in antagonizing AKI. Interestingly, the results also indicate that the upregulation of the E3 ligase HUWE1 causes the ubiquitination and degradation of MUTYH in tubular epithelial cells. HUWE1 knockout or treatment with the HUWE1 inhibitor BI8622 significantly protect against cisplatin-induced AKI. Taken together, these results suggest that the ubiquitin E3 ligase HUWE1-mediates ubiquitination and degradation of MUTYH can aggravate DNA damage in the nucleus and mitochondria and promote AKI. Targeting the HUWE1/MUTYH pathway may be a potential strategy for AKI treatment.

Overexpression of USP7 and HDM2 inactivates P53 signaling in tumor cells and facilitates their progression, but suppression of these targets by conventional strategies to reactivate P53 function remains a challenge. We applied polyQ sequences and target-interacting peptides to engineer polyQ fusion proteins that specifically sequester the targets, hence depleting their availabilities and modulating the P53 functionality. We have revealed that the designer fusion Atx793Q-N172-IRF (IRF sequence: SPGEGPSGTG) sequesters USP7 and/or HDM2 into aggregates and thereby increases the P53 level, but it depends on the IRF repeats fused, suggesting that depletion of the USP7 availability plays a dual role in controlling P53 stability. Direct sequestration of HDM2 by Atx793Q-N172-PMI (PMI: TSFAEYWNLLSP) remarkably reduces the protein level of soluble HDM2 and hence increases the P53 level, which consequently up-regulates expression of the downstream genes. The polyQ-fusion strategy is feasible to modulate the P53 stability and functionality, furnishing a therapeutic potential for cancers.

Providing an unbiased and comprehensive view of the DNA damage response in cells is critical in genotoxicity screening to identify substances that cause diverse types of DNA damage. Considering that S. cerevisiae is one of the most well-characterized model organisms in molecular and cellular biology, we created a map of the DNA damage response network containing the reported signaling pathways in yeast cells programmed to constitutively respond to DNA damage. A collection of GFP-fused S. cerevisiae yeast strains treated with typical genotoxic agents illuminated the cellular response to DNA damage, thereby identifying 15 protein biomarkers encompassing all eight documented DNA damage response pathways. Three statistical and one deep learning models were proposed to interpret the quantitative molecular toxicity end point, i.e. protein effect level index (PELI), by introducing weights of 15 biomarkers in genotoxicity assessment. The method based on standard deviation exhibited the best performance, with an R 2 of 0.916 compared to the SOS/umu test and an R 2 of 0.989 compared to the comet assay. The GFP-fused yeast-based proteomic assay has minute-level resolution of pathway activation data. It provides a concise alternative for fast, efficient, and mechanistic genotoxicity screening for various environmental and health applications.

Double-strand breaks (DSBs) in DNA pose a critical threat to genomic integrity, potentially leading to the onset and progression of various diseases, including cancer. Cellular responses to such lesions entail sophisticated repair mechanisms primarily mediated by non-homologous end joining (NHEJ) and homologous recombination (HR). Interestingly, the efficient recruitment of repair proteins and completion of DSB repair likely involve complex, inter-organelle communication and coordination of cellular components. In this study, we report a role of γ-tubulin in DSB repair. γ-tubulin is a major microtubule nucleation factor governing microtubule dynamics. We show that γ-tubulin is recruited to the site of DNA damage and is required for efficient DSB repair via both NHEJ and HR. Suppression of γ-tubulin impedes DNA repair and exacerbates DNA damage accumulation. Furthermore, γ-tubulin mediates the mobilization and formation of DNA damage foci, which serve as repair centers, thereby facilitating the recruitment of HR and NHEJ repair proteins on damaged chromatin. Finally, pharmacological inhibition of γ-tubulin enhances the cytotoxic effect of DNA-damaging agents, consistent with the DNA repair function of γ-tubulin, and underscoring the potential of its therapeutic intervention in cancer therapy.

Spermatogenesis-associated protein 2 (SPATA2) is primarily named for its important role in spermatogenesis. Its function in tumorigenesis remains elusive. Here, we used various bioinformatic tools to systematically analyze the expression patterns of SPATA2 in cancers, the correlation of SPATA2 expression with clinical parameters, genetic variation, methylation, phosphorylation, immune infiltration and immune therapy. SPATA2 is significantly upregulated in multiple cancers and its expression was associated with tumor stage, grade and serve as a potential prognostic marker in LIHC. Notably, SPATA2 was also linked to immune suppression, exhibiting positive correlations with immune checkpoint genes and immune suppressive cells such as regulatory T cells and MDSCs. Furthermore, SPATA2 interacted and co-expressed with proteins involved in DNA repair mechanisms, indicating its potential role in maintaining genomic stability. Finally, we conducted biological experiments to investigate the role of SPATA2 in LIHC. SPATA2 knockdown enhances the migration and proliferation capabilities of Hep-G2 and HuH7 cell lines. These findings underscore the significance of SPATA2 in cancer biology, suggests its role in both the tumor microenvironment and the tumor cell level and its potential as a prognostic marker and therapeutic target in oncology, particularly in LIHC.

The DNA damage response (DDR) is crucial for maintaining genomic stability and preventing the accumulation of mutations that can lead to various diseases, including cancer. The DDR is a complex cellular regulatory network that involves DNA damage sensing, signal transduction, repair, and cell cycle arrest. Modifications in histone phosphorylation play important roles in these processes, facilitating DNA repair factor recruitment, damage signal transduction, chromatin remodeling, and cell cycle regulation. The precise regulation of histone phosphorylation is critical for the effective repair of DNA damage, genomic integrity maintenance, and the prevention of diseases such as cancer, where DNA repair mechanisms are often compromised. Thus, understanding histone phosphorylation in the DDR provides insights into DDR mechanisms and offers potential therapeutic targets for diseases associated with genomic instability, including cancers.

Mutations in the tumor suppressor genes BRCA1 and BRCA2 are associated with the triple-negative breast cancer phenotype, particularly aggressive and hard-to-treat tumors lacking estrogen, progesterone, and human epidermal growth factor receptor 2. This research aimed to understand the metabolic and genetic links behind BRCA1 and BRCA2 mutations and investigate their relationship with effective therapies. Using the Cytoscape software, two networks were generated through a bibliographic analysis of articles retrieved from the PubMed-NCBI database. We identified 98 genes deregulated by BRCA mutations, and 24 were modulated by therapies. In particular, BIRC5, SIRT1, MYC, EZH2, and CSN2 are influenced by BRCA1, while BCL2, BAX, and BRIP1 are influenced by BRCA2 mutation. Moreover, the study evaluated the efficacy of several promising therapies, targeting only BRCA1/BRCA2-mutated cells. In this context, CDDO-Imidazolide was shown to increase ROS levels and induce DNA damage. Similarly, resveratrol decreased the expression of the anti-apoptotic gene BIRC5 while it increased SIRT1 both in vitro and in vivo. Other specific drugs were found to induce apoptosis selectively in BRCA-mutated cells or block cell growth when the mutation occurs, i.e., 3-deazaneplanocin A, genistein or daidzein, and PARP inhibitors. Finally, over-representation analysis on the genes highlights ferroptosis and proteoglycan pathways as potential drug targets for more effective treatments.

Identification of ARID1A/ATR synthetic lethality led to ATR inhibitor phase II trials in ovarian clear cell carcinoma (OCCC), a cancer of unmet need. Using multiple CRISPR-Cas9 mutagenesis and interference screens, we show that inactivation of protein phosphatase 2A (PP2A) subunits, including PPP2R1A, enhance ATRi sensitivity in ARID1A mutant OCCC. Analysis of a new OCCC cohort indicates that 52% possess oncogenic PPP2R1A p.R183 mutations and of these, one half possessed both ARID1A as well as PPP2R1A mutations. Using CRISPR-prime editing to generate new isogenic models of PPP2R1A mutant OCCC, we found that PPP2R1A p.R183W and p.R183P mutations cause ATRi-induced S phase stress, premature mitotic entry, genomic instability and ATRi sensitivity in OCCC tumour cells. p.R183 mutation also enhanced both in vitro and in vivo ATRi sensitivity in preclinical models of ARID1A mutant OCCC. These results argue for the assessment of PPP2R1A mutations as a biomarker of ATRi sensitivity.

Repair of double strand breaks (DSBs) by RNA-binding proteins (RBPs) is vital for ensuring genome integrity. DSB repair is accompanied by local transcriptional repression in the vicinity of transcriptionally active genes, but the mechanism by which RBPs regulate transcriptional regulation is unclear. Here, we demonstrated that RBP hnRNPA2B1 functions as a RNA polymerase-associated factor that stabilizes the transcription complex under physiological conditions. Following a DSB, hnRNPA2B1 is released from damaged chromatin, reducing the efficiency of RNAPII complex assembly, leading to local transcriptional repression. Mechanistically, SIRT6 deacetylates hnRNPA2B1 at K113/173 residues, enforcing its rapid detachment from DSBs. This process disrupts the integrity of the RNAPII complex on active chromatin, which is a pre-requisite for transient but complete repression of local transcription. Functionally, the overexpression of an acetylation mimic stabilizes the transcription complex and facilitates the functioning of the transcription machinery. hnRNPA2B1 acetylation status was negatively correlated with SIRT6 expression, and acetylation mimic enhanced radio-sensitivity in vivo. Our findings demonstrate that hnRNPA2B1 is crucial for transcriptional repression. We have uncovered the missing link between DSB repair and transcriptional regulation in genome stability maintenance, highlighting the potential of hnRNPA2B1 as a therapeutic target.

Glioblastoma (GBM) is the most common malignant tumour of the central nervous system. Despite recent advances in multimodal GBM therapy incorporating surgery, radiotherapy, systemic therapy (chemotherapy, targeted therapy), and supportive care, the overall survival (OS) remains poor, and long-term survival is rare. Currently, the primary obstacles hindering the effectiveness of GBM treatment are still the blood-brain barrier and tumor heterogeneity. In light of its substantial advantages over conventional therapies, such as strong penetrative ability and minimal side effects, low-frequency magnetic fields (LF-MFs) therapy has gradually caught the attention of scientists.

In this review, we shed the light on the current status of applying LF-MFs in the treatment of GBM. We specifically emphasize our current understanding of the mechanisms by which LF-MFs mediate anticancer effects and the challenges faced by LF-MFs in treating GBM cells. Furthermore, we discuss the prospective applications of magnetic field therapy in the future treatment of GBM. Key scientific concepts of review: The review explores the current progress on the use of LF-MFs in the treatment of GBM with a special focus on the potential underlying mechanisms of LF-MFs in anticancer effects. Additionally, we also discussed the complex magnetic field features and biological characteristics related to magnetic bioeffects. Finally, we proposed a promising magnetic field treatment strategy for future applications in GBM therapy.

Glycerophospholipid biosynthesis is crucial not only for providing structural components required for membrane biogenesis during cell proliferation but also for facilitating membrane remodeling under stress conditions. The biosynthetic pathways for glycerophospholipid tails, glycerol backbones, and diverse head group classes intersect with various other metabolic processes, sharing intermediary metabolites. Recent studies have revealed intricate connections between glycerophospholipid synthesis and nuclear metabolism, including metabolite-mediated crosstalk with the epigenome, signaling pathways that govern genome integrity, and CTP-involved regulation of nucleotide and antioxidant biosynthesis. This review highlights recent advances in understanding the functional roles of glycerophospholipid biosynthesis beyond their structural functions in budding yeast and mammalian cells. We propose that glycerophospholipid biosynthesis plays an integrative role in metabolic regulation, providing a new perspective on lipid biology.

Drug resistance significantly limits the efficacy of chemotherapy. The DNA mismatch repair (MMR) system maintains genomic stability by correcting DNA errors. During DNA-damaging treatments, cancer cells transiently increase their adaptive mutability, also known as microsatellite instability (MSI), to evade therapeutic pressure through MMR downregulation, conferring drug resistance. However, an understanding of the underlying mechanisms of MMR protein downregulation under DNA-damaging drugs remains limited. Our study reveals a negative correlation between SIRT7 protein levels and MMR core protein MSH2 levels in cervical and lung cancer tissues. SIRT7 destabilizes MSH2, promoting MSI and mutagenesis. Molecularly, DNA damage triggers ATM kinase-dependent phosphorylation and subcellular redistribution of SIRT7. Phosphorylated SIRT7 interacts with and deacetylates MSH2, impairing MMR, and inducing MSI and drug resistance. Our findings suggest that SIRT7 drives MMR downregulation under therapeutic stress and that ATM-dependent phosphorylation of SIRT7 may serve as a predictive biomarker for chemotherapeutic efficacy and a target for cancer treatment.

The genetic information on organisms is stored in the cell nucleus in the form of higher-ordered DNA structures. Here, we use DNA framework nanostructures (DFNs) to simulate the compaction and stacking density of nucleosome DNA for precise conformational and structure determination, particularly the dynamic structural changes, preferential reaction regions, and sites of DFNs during the reactive oxygen species (ROS) reaction process. By developing an atomic force microscopy-based single-particle analysis (SPA) data reconstruction method to collect and reanalyze imaging information, we demonstrate that the geometric morphology of DFNs constrains their reaction kinetics with ROS, where local mechanical stress and regional base distribution are two key factors affecting their kinetics. Furthermore, we plot the reaction process diagram for ROS and DFNs, showing the reaction process and intermediate products with individual activation energies. This SPA method offers new research tools and insights for studying the dynamic changes of highly folded and organized DNA structural domains within the nucleus and helps to reveal the key mechanisms behind their functional differences in topologically associating domains.

Hepatocellular carcinoma (HCC) treatment remains challenging, particularly for immune checkpoint inhibitors (ICIs) non-response patients. Spatial transcriptome (ST) data and machine learning algorithms offer new insights into understanding HCC heterogeneity and ICIs resistance mechanisms.

Utilizing ST data from HCC patients on ICIs treatment, we analyzed pathway activity and immune infiltration. We combined 167 machine learning models to develop a G2M-checkpoint related signature (G2MRS) based on differential gene expression. The four cohorts and in-house cohort was used to validate G2MRS, and KPNA2's role was further examined through in vitro experiments in two different liver cancer cell lines.

Our analysis revealed a distinct suppressive immune barrier structure (SIBS) in ICIs non-response patients, associated with upregulated G2M-checkpoint levels. G2MRS, consisting of KPNA2, CENPA, and UCK2, accurately predicted HCC prognosis and ICIs response. Further in vitro experiments demonstrated KPNA2's role in regulating migration, proliferation, and apoptosis in liver cancer.

This study highlights the importance of spatial heterogeneity and machine learning in refining HCC prognosis and ICIs response prediction. G2MRS and KPNA2 emerge as promising biomarkers for personalized HCC management.

5-fluorouracil (5-FU) is the most widely used anti-pyrimidine drug that exerts its cytotoxic effect by causing DNA damage. The Wnt/β-catenin pathway has been considered a promising strategy to improve chemosensitivity by enhancing the DNA damage response of chemotherapy drugs. Combination therapies against cancers could inevitably affect endogenous levels of ribonucleotides (RNs) and deoxyribonucleotides (dRNs) which are critical for DNA synthesis and repair. However, exploring satisfactory Wnt/β-catenin inhibitors for synergistic therapy through regulating RNs and dRNs remains challenging.

Here, aloe vera-derived carbon dots (A-CDs) with good bioactivity were synthesized via a one-step hydrothermal process, demonstrating both intrinsic Wnt/β-catenin inhibition and bioimaging capabilities to overcome the limitations of conventional Wnt/β-catenin inhibitors. The as-prepared A-CDs were further served as the transport vehicle for 5-FU, facilitating synergistic combination therapy by inhibiting the Wnt/β-catenin pathway, which could possibly accelerate nucleotide imbalance of dATP, ATP, TMP, and dUMP, ultimately leading to enhanced 5-FU efficiency. Additionally, the tumor-targeted material (HA-CDs@5-FU) was synthesized by modifying hyaluronic acid (HA) onto CDs@5-FU and exhibited superior antitumor efficacy in vivo with negligible side effects.

Overall, this study provided a novel strategy for Wnt/β-catenin inhibition and synergistic therapy, providing insights into the application of nano-agents in cancer therapy.

Glioblastoma multiforme (GBM) is the most malignant brain tumor, with radiotherapy frequently employed following surgical resection. However, conventional radiation therapies often yield suboptimal results. This study investigated the effects of X-ray and carbon ion irradiation on the glioblastoma cell line U251 to assess the distinctive advantages of carbon ion treatment and explore mechanisms for overcoming radiation resistance. The findings indicated that carbon ion irradiation more effectively inhibited colony formation and induced more severe apoptosis and cell cycle disorder in U251 cells. Immunofluorescence assays revealed larger and more abundant ϒ-H2AX and 53BP1 foci in the carbon ion irradiation group. Western blot analysis demonstrated that carbon ion-induced DNA damage repair involved a complex array of pathways, with the RAD51-mediated homologous recombination (HR) pathway being predominant, while the Rad23B-mediated nucleotide excision repair (NER) pathway and XRCC1-mediated base excision repair (BER) were more relevant in response to X-ray irradiation. These results suggest that carbon ion irradiation may overcome radioresistance by inducing more complex DNA damage and apoptosis, thus providing insights for targeting new strategies in combining gene therapy with radiotherapy.

Historically considered downstream effects of tumorigenesis-arising from changes in DNA content or chromatin organization-nuclear alterations have long been seen as mere prognostic markers within a genome-centric model of cancer. However, recent findings have placed the nuclear envelope (NE) at the forefront of tumor progression, highlighting its active role in mediating cellular responses to mechanical forces. Despite significant progress, the precise interplay between NE components and cancer progression remains under debate. In this review, we provide a comprehensive and up-to-date overview of how changes in NE composition affect nuclear mechanics and facilitate malignant transformation, grounded in the latest molecular and functional studies. We also review recent research that uses advanced technologies, including artificial intelligence, to predict malignancy risk and treatment outcomes by analyzing nuclear morphology. Finally, we discuss how progress in understanding nuclear mechanics has paved the way for mechanotherapy-a promising cancer treatment approach that exploits the mechanical differences between cancerous and healthy cells. Shifting the perspective on NE alterations from mere diagnostic markers to potential therapeutic targets, this review calls for further investigation into the evolving role of the NE in cancer, highlighting the potential for innovative strategies to transform conventional cancer therapies.

Chemotherapy with anthracycline antibiotics is a common method of treating tumors of various etiologies. To create more highly effective cytostatics based on daunorubicin, we used the method of reductive amination using polyalkoxybenzaldehydes. The obtained derivatives of the anthracycline structure have much greater cytotoxicity compared to daunorubicin due to increased affinity for DNA, the ability to disrupt the cell cycle, and their inhibition of the glycolysis process, which is confirmed by data from extensive biological studies and the results of molecular modeling.

Superior to traditional multiplex photoelectrochemical (PEC) sensors, integrated multitarget assay on a single reconstructive electrode interface is promising in real-time detection through eliminating the need of specialized instrumentation and cumbersome interfacial modifications. Current interface reconstruction approaches including pH modulation and bioenzyme cleavage involve biohazardous and time-consuming operations, which cannot meet the demand for rapid, eco-friendly, and portable detection, which are detrimental to the development of multiplex PEC sensors toward portability. Herein, we report a pioneer work on IR-driven "four-to-one" multisignal conditioning to facile reconfigure electrode interface for multitarget detection via photoelectrochemical/photothermal dual mode. The copper sulfide quantum dot (CuS QD) with excellent photoelectrochemical properties and a photothermal effect is first labeled on DNA S2. Once the CuS QD-S2 complementarily pairs with the DNA S3 on the photocathode surface, thermal-responsive triple DNA is formed, and the photocurrent and photothermal dual-mode signals for one target assay are produced. Upon the dissociation of the triple DNA by IR irradiation, the electrode interface is reconfigured for the self-calibrating dual-mode detection of another target. The feasibility of the IR-driven multisignal conditioning sensor is confirmed by detecting coexistent antibiotics kanamycin (KANA) and neomycin (NEO) in complex real samples. The low-loss interface reconfiguration and rapid "four-to-one" multisignal modulation highlight a broad prospect for self-calibrating multiplex assay in the fields of environment, medicine, and food safety.