Knowledge regarding adenocarcinoma of the rete testis (ACRT) is extremely limited due to its scarcity.

This study enrolled 18 patients with ACRT from multiple institutions. Clinicopathological and immunohistochemical features were investigated, together with a comprehensive review of 95 previously reported cases. One case was assessed using next-generation sequencing (NGS). The median age of the patient cohort was 54 years (range = 20-69 years), with the majority presenting with a testicular mass (13 of 18); predominantly right-sided (11 of 18). Six patients died within the second year following diagnosis. The morphology of ACRT spans a wide spectrum, including newly identified mucinous carcinoid-like features, with mucous cells floating in mucus and signet-ring cells. Notably, transition from a benign to a malignant rete epithelium was noted in 38.9% of cases (seven of 18). Immunohistochemically, tumour cells most frequently showed strong positivity for CK7 (12 of 16) and CK20 (10 of 17), with occasionally positivity for calretinin (three of 16), WT-1 (two of 17) and PAX-8 (two of 15). According to NGS in a single case, MET was amplified, leading to the patient benefiting from mesenchymal-epidermal transition factor (MET) inhibitors. Furthermore, MET amplification was assessed in 13 cases using fluorescence in-situ hybridisation and detected in two cases (15.4%). No significant correlation between MET amplification and mesenchymal-epidermal transition factor (MET) levels was observed in the cases studied.

Primary ACRT is a rare malignant tumour which poses a diagnostic challenge, and is associated with poor prognosis. Cases of ACRT with MET amplification might represent promising candidates for the treatment with MET inhibitors.

Aberrant regulation of MET receptor tyrosine kinase activity is a frequent event in non-small cell lung cancer (NSCLC), even though the frequency of oncogenic driver mutations of MET is low. Our discovery of oncogenic MET exon 14 skipping mutations, the characterization of the first prototype MET kinase inhibitor, and characterization of MET expression levels have led the way to novel therapeutic approaches with improved outcomes in NSCLC. MET exon 14 mutations are the most consequential but not the only alterations that can be targeted through small molecule tyrosine kinase inhibitors. The abundant expression of cellular MET (c-MET) in cancer cells has provided new opportunities for immuno-oncology approaches in a broader patient population, and the integration of MET-targeted personalized medicine with immunotherapy has not been fully exploited yet. Here, we highlight essential facets of MET as a therapeutic target in NSCLC and provide an outlook for future approaches.

The MET proto-oncogene (MET) plays a crucial role as an oncogenic driver gene in non-small cell lung cancer (NSCLC). At present, numerous types of MET exon 14 (METex14) skipping mutation have been identified, but different splice variants often exhibit varying treatment responses. There is currently no standardized treatment approach for rare METex14 mutation after resistance to epidermal growth factor receptor tyrosine kinases inhibitor (EGFR-TKI). Herein, we present for the first time a case of advanced lung adenocarcinoma with a novel METex14 skipping mutation following resistance to EGFR-TKI and subsequent sensitivity to savolitinib. In addition, the patient developed a novel METex14 skipping mutation after EGFR-TKI resistance, which we suspect may be a potential new mechanism of EGFR-TKI resistance that has not been reported.

We conducted surgical specimen pathology diagnosis and next-generation sequencing (NGS) of peripheral blood to ascertain the patient's pathological and molecular characteristics.

NGS testing identified a novel METex14 (c.2888-23_2888-8del) skipping mutation in the patient with advanced lung adenocarcinoma who developed resistance to EGFR-TKI, suggesting its potential involvement as one of the mechanisms underlying the resistance to EGFR-TKI. Following administration of savolitinib with a daily dose of 400 mg, the patient exhibited a partial response and achieved progression-free survival (PFS) exceeding 8 months.

The case presents a novel METex14 skipping mutation that emerges subsequent to the progression of advanced lung adenocarcinoma following EGFR-TKI treatment. Importantly, this mutation may serve as one of the mechanisms contributing to resistance against EGFR-TKI and exhibit sensitivity towards savolitinib treatment, providing reference for future similar cases in terms of treatment options.

The emergence of targeted therapies for MET exon 14 (METex14) skipping mutations has significantly changed the treatment landscape for NSCLC and other solid tumors. The skipping of METex14 results in activating the MET-HGF pathway and promoting tumor cell proliferation, migration, and preventing apoptosis. Type Ib MET inhibitors, designed to selectively target the "DFG-in" conformation of MET, characteristically bind to the ATP-binding pocket of MET in a U-shaped conformation, extending into the solvent-accessible region and interact strongly with residue Y1230 through π-π interactions, have shown remarkable efficacy in treating METex14-altered NSCLC, including cases with brain metastases (BMs). Notably, vebreltinib and capmatinib have demonstrated superior blood-brain barrier (BBB) permeability in both computational and experimental models, highlighting their potential for treating the central nervous system (CNS) metastases. P-glycoprotein (P-gp) is highly expressed in the BBB, which limits the brain uptake of many highly lipophilic drugs. Despite challenges posed by P-gp mediated efflux, vebreltinib has emerged as a promising candidate for CNS treatment due to its favorable pharmacokinetic profile and minimal susceptibility to P-gp efflux. This study underscores the importance of molecular dynamics simulations in predicting drug efficacy and BBB penetration, providing valuable insights for the development of CNS-targeted metastases therapies.

In hereditary papillary renal cell carcinoma (HPRCC), the hepatocyte growth factor receptor (MET) receptor tyrosine kinase (RTK) mutations recorded to date are located in the kinase domain and lead to constitutive MET activation. This contrasts with MET mutations identified in non-small-cell lung cancer (NSCLC), which lead to exon 14 skipping and deletion of a regulatory domain: In this latter case, the mutated receptor still requires ligand stimulation. Sequencing of MET in samples from 158 HPRCC and 2808 NSCLC patients revealed 10 uncharacterized mutations. Four of these, all found in HPRCC and leading to amino acid substitutions in the N-lobe of the MET kinase, proved able to induce cell transformation, which was further enhanced by hepatocyte growth factor (HGF) stimulation: His1086Leu, Ile1102Thr, Leu1130Ser, and Cis1125Gly. Similar to the variant resulting in MET exon 14 skipping, the two N-lobe MET variants His1086Leu and Ile1102Thr were found to require stimulation by HGF in order to strongly activate downstream signaling pathways and epithelial cell motility. The Ile1102Thr mutation also displayed transforming potential, promoting tumor growth in a xenograft model. In addition, the N-lobe-mutated MET variants were found to trigger a common HGF-stimulation-dependent transcriptional program, consistent with an observed increase in cell motility and invasion. Altogether, this functional characterization revealed that N-lobe variants still require ligand stimulation, in contrast to other RTK variants. This suggests that HGF expression in the tumor microenvironment is important for tumor growth. The sensitivity of these variants to MET inhibitors opens the way for use of targeted therapies for patients harboring the corresponding mutations.

Mutations in the kinase and juxtamembrane domains of the MET Receptor Tyrosine Kinase are responsible for oncogenesis in various cancers and can drive resistance to MET-directed treatments. Determining the most effective inhibitor for each mutational profile is a major challenge for MET-driven cancer treatment in precision medicine. Here, we used a deep mutational scan (DMS) of ~5764 MET kinase domain variants to profile the growth of each mutation against a panel of 11 inhibitors that are reported to target the MET kinase domain. We validate previously identified resistance mutations, pinpoint common resistance sites across type I, type II, and type I ½ inhibitors, unveil unique resistance and sensitizing mutations for each inhibitor, and verify non-cross-resistant sensitivities for type I and type II inhibitor pairs. We augment a protein language model with biophysical and chemical features to improve the predictive performance for inhibitor-treated datasets. Together, our study demonstrates a pooled experimental pipeline for identifying resistance mutations, provides a reference dictionary for mutations that are sensitized to specific therapies, and offers insights for future drug development.

The cellular-mesenchymal to epithelial transition factor (MET) gene plays a crucial role in maintaining cell homeostasis, motility, and apoptosis. In cancer, MET gene alterations promote tumour cell proliferation, invasion and metastasis. In non-small cell lung cancer (NSCLC), MET gene alterations include MET exon 14 (METex14) skipping mutation (METΔ14ex), MET amplification (METamp), MET fusion, and MET tyrosine kinase domain missense mutations (MET-TKD) and MET protein overexpression. Among them, the METΔ14ex is an independent driver gene of NSCLC. Three to four per cent of NSCLC patients carry METΔ14ex, and these patients have a poor prognosis and respond poorly to conventional chemotherapy. Small molecule highly selective MET inhibitors such as carmatinib, tepotinib, and cervotinib have shown promising efficacy and safety in clinical trials. Monoclonal antibodies, bispecific antibodies, antibody conjugate drugs, and immune checkpoint inhibitors provide more treatment space for patients with METΔ14ex. In this review, we summarize the current application and research of MET inhibitors and immune checkpoint inhibitors in NSCLC with METΔ14ex and provide recommendations for precise treatment of NSCLC patients with MET gene changes mutations. It also provides new ideas for solving the problems of synergistic effect and drug resistance in targeted therapy and immunotherapy.

Mesenchymal-epithelial transition factor (MET) alterations are rare oncogenic drivers in patients with non-small cell lung cancer (NSCLC). This study characterized patients with advanced NSCLC harboring MET exon 14 (METex14) skipping and MET amplification (METamp) in routine clinical practice in the United States.

Using electronic medical record data from the ConcertAI Oncology Dataset (2004-2022), 2 patient cohorts were identified: 1 with METex14 skipping with or without METamp, and 1 with METamp without METex14 skipping. A subgroup with METamp and concomitant epidermal growth factor receptor (EGFR) mutations who had received EGFR-tyrosine kinase inhibitors (TKIs) was also analyzed. Patient characteristics, treatment patterns and outcomes were described.

93 patients with advanced NSCLC harboring METex14 skipping and 164 with advanced NSCLC harboring METamp were identified. Established oncogenic drivers other than MET were less frequent in the METex14 skipping cohort than the METamp cohort. In both cohorts, first-line chemotherapy use decreased over time while immune checkpoint inhibitor (ICI) and MET inhibitor use increased. Treatment patterns were heterogeneous, with patients receiving multiple drug classes across therapy lines. Outcomes were better for patients with METex14 skipping NSCLC who received targeted therapies or ICIs versus chemotherapy. Subgroup analyses of EGFR-TKI-treated patients with METamp indicated poor outcomes.

Patients with METex14 skipping and/or METamp NSCLC require targeted and personalized treatment approaches to optimize treatment effect and have an unmet medical need. With targeted therapies recently available and others under exploration, treatment outcomes could significantly improve for patients with NSCLC harboring these rare drivers.

Mesenchymal to epithelial transition factor (MET) dysregulation in non-small-cell-lung-cancer (NSCLC) is understudied, with scant data on treatment outcomes.

We retrospectively examined 160 NSCLC patients: 125 with primary MET mutations (further classified into MET exon 14 (METex14) skipping mutations and primary MET amplifications) and 35 with secondary MET amplifications. Patients underwent varied treatments: Chemotherapy, Immune monotherapy, Crizotinib, or Savolitinib. Secondary MET amplification patients were grouped by treatment: Group A (Class Ib MET-TKI with third-generation EGFR-TKI), Group B (Crizotinib with first-generation EGFR-TKI), and Group C (Crizotinib alone). One hundred and thirty patients have completed the whole treatment process. Their data were included in the study's survival analysis (included 95 patients with primary MET mutations and 35 patients with secondary MET amplifications).

Among METex14 skipping mutations patients (n = 57), median progression free survival (PFS) was: Chemotherapy 7.64 m, Crizotinib 8.5 m, Savolitinib 9.3 m, and Immunotherapy 3.87 m. Targeted therapies and chemotherapy significantly outperformed Immunotherapy. Sub-group analysis indicated splice donor region mutations benefited more than those at the polypyrimidine tract (9.23 m vs. 4.03 m, P = 0.038). For primary MET amplifications (n = 38), PFS was: Chemotherapy 2.84 m, Crizotinib 3.80 m, Savolitinib 5.23 m, and Immunotherapy 3.30 m. Patients with copy number (CN) > 5 had longer PFS than CN ≤ 5 (5.17 m vs. 3.44 m, P = 0.039). In secondary MET amplifications (n = 35), Group A and B had similar PFS (6.77 m and 6.57 m) versus Group C (3.13 m). Dual-target therapy PFS showed no difference between CN ≤ 5 and CN > 5 (8.63 m vs. 6.27 m, P = 0.29).

NSCLC patients with METex14 skipping mutations benefit more from targeted therapies, especially those with splice donor mutations. MET amplification patients benefit universally from targeted therapies; primary MET amplifications show higher benefits with increased copy numbers. For secondary MET amplifications post-EGFR-TKI resistance, dual-target therapy surpasses Crizotinib monotherapy, independent of MET copy number.

The hepatocyte growth factor receptor (MET) is a receptor tyrosine kinase (RTK) that mediates the activity of a variety of downstream pathways upon its activation. These pathways regulate various physiological processes within the cell, including growth, survival, proliferation, and motility. Under normal physiological conditions, this allows MET to regulate various development and regenerative processes; however, mutations resulting in aberrant MET activity and the consequent dysregulation of downstream signaling can contribute to cellular pathophysiology. Mutations within MET have been identified in a variety of cancers and have been shown to mediate tumorigenesis by increasing RTK activity and downstream signaling. In lung cancer specifically, a number of patients have been identified as possessing MET alterations, commonly receptor amplification (METamp) or splice site mutations resulting in loss of exon 14 (METex14). Due to MET's role in mediating oncogenesis, it has become an attractive clinical target and has led to the development of various targeted therapies, including MET tyrosine kinase inhibitors (TKIs). Unfortunately, these TKIs have demonstrated limited clinical efficacy, as patients often present with either primary or acquired resistance to these therapies. Mechanisms of resistance vary but often occur through off-target or bypass mechanisms that render downstream signaling pathways insensitive to MET inhibition. This review provides an overview of the therapeutic landscape for MET-positive cancers and explores the various mechanisms that contribute to therapeutic resistance in these cases.

Primary pulmonary lymphoepithelial carcinoma (pLEC) is a subtype of non-small cell lung cancer (NSCLC) characterized by Epstein-Barr virus (EBV) infection. However, the molecular pathogenesis of pLEC remains poorly understood.

In this study, we explored pLEC using whole-exome sequencing (WES) and RNA-whole-transcriptome sequencing (RNA-seq) technologies. Datasets of normal lung tissue, other types of NSCLC, and EBV-positive nasopharyngeal carcinoma (EBV+-NPC) were obtained from public databases. Furthermore, we described the gene signatures, viral integration, cell quantification, cell death and immune infiltration of pLEC.

Compared with other types of NSCLC and EBV+-NPC, pLEC patients exhibited a lower somatic mutation burden and extensive copy number deletions, including 1p36.23, 3p21.1, 7q11.23, and 11q23.3. Integration of EBV associated dysregulation of gene expression, with CNV-altered regions coinciding with EBV integration sites. Specifically, ZBTB16 and ERRFI1 were downregulated by CNV loss, and the FOXD family genes were overexpressed with CNV gain. Decreased expression of the FOXD family might be associated with a favorable prognosis in pLEC patients, and these patients exhibited enhanced cytotoxicity.

Compared with other types of NSCLC and NPC, pLEC has distinct molecular characteristics. EBV integration, the aberrant expression of genes, as well as the loss of CNVs, may play a crucial role in the pathogenesis of pLEC. However, further research is needed to assess the potential role of the FOXD gene family as a biomarker.

Alternative splicing (AS) is a process that facilitates the differential inclusion of exonic sequences from precursor messenger RNAs, significantly enhancing the diversity of the transcriptome and proteome. In cancer, pathogenic AS events are closely related to cancer progression. This study aims to investigate the role and regulatory mechanisms of AS in gastric cancer (GC).

We analyzed AS events in various tumor samples and identified hnRNPU as a key splicing factor in GC. The effects of hnRNPU on cancer progression were assessed through in vitro and in vivo experiments. Gene knockout models and the FTO inhibitor (meclofenamic acid) were used to validate the interaction between hnRNPU and FTO and their impact on AS.

We found that hnRNPU serves as a key splicing factor in GC, and its high expression is associated with poor clinical prognosis. Genetic depletion of hnRNPU significantly reduced GC progression. Mechanistically, the m6A demethylase FTO interacts with hnRNPU transcripts, decreasing the m6A modification levels of hnRNPU, which leads to exon 14 skipping of the MET gene, thereby promoting GC progression. The FTO inhibitor meclofenamic acid effectively inhibited GC cell growth both in vitro and in vivo.

The FTO/hnRNPU axis induces aberrant exon skipping of MET, thereby promoting GC cell growth. Targeting the FTO/hnRNPU axis may interfere with abnormal AS events and provide a potential diagnostic and therapeutic strategy for GC.

Human cervix adenocarcinoma (CC) caused by papillomavirus is the third most common cancer among female malignant tumors. Bioactive compounds such as cyclodipeptides (CDPs) possess cytotoxic effects in human cervical cancer HeLa cells mainly by blocking the PI3K/Akt/mTOR pathway and subsequently inducing gene expression by countless transcription regulators. However, the upstream elements of signaling pathways have not been well studied.

To elucidate the cytotoxic and antiproliferative responses of the HeLa cell line to CDPs by a transcriptomic analysis previously carried out, we identified by immunochemical analyses, differential expression of genes related to the hepatocyte growth factor/mesenchymal-epithelial transition factor (HGF/MET) receptors. Furthermore, molecular docking was carried out to evaluate the interactions of CDPs with the EGF and MET substrate binding sites.

Immunochemical and molecular docking analyses suggest that the HGF/MET receptor participation in CDPs cytotoxic effect was independent of the protein expression levels. However, protein modulation of downstream Met-targets occurred due to the inhibition of phosphorylation of the HGF/MET receptor. Results suggest that the antiproliferative and cytotoxicity of CDPs in HeLa cells involve the HGF/MET receptor upstream of PI3K/Akt/mTOR pathway; assays with the human breast cancer MCF-7 and MDA-MB-231cell lines supported the finding.

Data provide new insights into the molecular mechanisms involved in CDPs cytotoxicity and antiproliferative effects, suggesting that the signal transduction mechanism may be related to the inhibition of the phosphorylation of the EGF/MET receptor at the level of substrate binding site by an inhibition mechanism similar to that of Gefitinib and Foretinib anti-neoplastic drugs.

Targeted therapy indications for actionable variants in non-small-cell lung cancer (NSCLC) have primarily been studied in Caucasian populations, with limited data on Latin American patients. This study utilized a 52-genes next-generation sequencing (NGS) panel to analyze 1560 tumor biopsies from NSCLC patients in Chile, Brazil, and Peru. The RNA sequencing reads and DNA coverage were correlated to improve the detection of the actionable MET exon 14 skipping variant (METex14). The pathogenicity of MET variants of uncertain significance (VUSs) was assessed using bioinformatic methods, based on their predicted driver potential. The effects of the predicted drivers VUS T992I and H1094Y on c-MET signaling activation, proliferation, and migration were evaluated in HEK293T, BEAS-2B, and H1993 cell lines. Subsequently, c-Met inhibitors were tested in 2D and 3D cell cultures, and drug affinity was determined using 3D structure simulations. The prevalence of MET variants in the South American cohort was 8%, and RNA-based diagnosis detected 27% more cases of METex14 than DNA-based methods. Notably, 20% of METex14 cases with RNA reads below the detection threshold were confirmed using DNA analysis. The novel actionable T992I and H1094Y variants induced proliferation and migration through c-Met/Akt signaling. Both variants showed sensitivity to crizotinib and savolitinib, but the H1094Y variant exhibited reduced sensitivity to capmatinib. These findings highlight the importance of RNA-based METex14 diagnosis and reveal the drug sensitivity profiles of novel actionable MET variants from an understudied patient population.

Background/Objectives: Uveal melanomas (UMs) are rare but often deadly malignancies that urgently require viable treatment options. UMs often exhibit tumour heterogeneity, with macroscopic and microscopic differences in morphology between different regions of the same tumour. However, to date, the clinical significance of this and how it may help guide personalised therapy have not been realised. Methods: Using targeted DNA and RNA sequencing of a small case series of large, high-risk primary UMs, we explored whether morphologically distinct regions of the same tumour were associated with distinct molecular profiles. Results: In four of the seven tumours analysed, we detected different sets of genetic variants following the separate analysis of microdissected melanotic and amelanotic regions of the same tumour. These included a MET exon 14 skipping RNA transcript that predicts sensitivity to crizotinib and variants in other genes that are important in active clinical trials for patients with UM and advanced solid tumours. The integration of TCGA data also identified recurrent mutational events in genes that were not previously implicated in UM development (FANCA, SLX4, BRCA2, and ATRX). Conclusions: Our findings show that the molecular analysis of spatially separated and morphologically distinct regions of the same tumour may yield additional, therapeutically relevant genetic variants in uveal melanomas and have implications for the future molecular testing of UMs to identify targeted therapies.

MET gene exon 14 skipping was identified as a potential driver mutation that occurs in approximately 3%-4% of patients with nonsmall cell lung cancer (NSCLC), typically in the absence of other driver mutations. Capmatinib and tepotinib were the first MET- tyrosine kinase inhibitors (MET-TKIs) approved by the FDA and PMDA, specifically for patients with metastatic NSCLC. Several studies have reported acquired resistance after MET-TKI treatment for MET mutation-positive NSCLC. Sequencing of the MET kinase region of resistant cell lines revealed secondary mutations at residues D1228 and Y1230 that were sensitive to type II MET-TKIs, such as cabozantinib. This suggested that sequential administration of other MET-TKIs may overcome the development of secondary mutations after acquired resistance in MET exon 14 mutation-positive NSCLC.

We designed the single arm phase II study CAPTURE Trial to assess the efficacy of cabozantinib in patients with advanced/metastatic NSCLC with activating MET exon 14 alterations who developed acquired resistance to tepotinib or capmatinib, as well as after 2 prior chemotherapy regimens that included platinum and docetaxel. The primary endpoint was objective response rate by independent review committees. The sample size (n = 30) is calculated by assuming a threshold response rate of 5% and an expected response rate of 25%. Recruitment began in August 2024.

This ongoing study aimed to evaluate the safety and efficacy of cabozantinib after acquired resistance to tepotinib or capmatinib.

Mutations in the kinase and juxtamembrane domains of the MET Receptor Tyrosine Kinase are responsible for oncogenesis in various cancers and can drive resistance to MET-directed treatments. Determining the most effective inhibitor for each mutational profile is a major challenge for MET-driven cancer treatment in precision medicine. Here, we used a deep mutational scan (DMS) of ~5,764 MET kinase domain variants to profile the growth of each mutation against a panel of 11 inhibitors that are reported to target the MET kinase domain. We validate previously identified resistance mutations, pinpoint common resistance sites across type I, type II, and type I ½ inhibitors, unveil unique resistance and sensitizing mutations for each inhibitor, and verify non-cross-resistant sensitivities for type I and type II inhibitor pairs. We augment a protein language model with biophysical and chemical features to improve the predictive performance for inhibitor-treated datasets. Together, our study demonstrates a pooled experimental pipeline for identifying resistance mutations, provides a reference dictionary for mutations that are sensitized to specific therapies, and offers insights for future drug development.

To provide patients with MET-mutated advanced non-small cell lung cancer (METmut aNSCLC) access to crizotinib, further substantiate evidence of its efficacy and safety in this setting, and find potential biomarkers for nonresponse.

In the Drug Rediscovery Protocol (NCT0295234), patients with an actionable molecular profile are treated with off-label registered drugs. Both treated and untreated patients with aNSCLC harboring MET exon 14 skipping or other MET mutations received crizotinib 250 mg BID until disease progression or intolerable toxicity. Primary endpoints were clinical benefit [CB: RECIST v1.1 confirmed partial response, complete response (CR), or stable disease ≥16 weeks] and safety. Patients were enrolled using a Simon-like two-stage design, with eight patients in stage I and if ≥1/8 patients had CB, 24 patients in stage II. Whole-genome sequencing and RNA sequencing were performed on baseline biopsies.

Between September 2018 and October 2022, 30 patients started treatment, and 24 were response-evaluable after completing ≥1 full treatment cycle. Two patients (8.3%) achieved CR, 13 (54.2%) partial response, and two (8.3%) stable disease. The CB rate was 70.8% [95% confidence interval (CI), 48.9-87.4], and the objective response rate was 62.5% (95% CI, 40.6-81.2). After 21.2-month median follow-up, median duration of response, progression-free survival, and overall survival were 9.3 (95% CI, 6.5-not available), 10.2 (95% CI, 6.0-20.1), and 13.0 months (95% CI, 9.0-not available), respectively. Twenty-three treatment-related grade ≥ 3 adverse events occurred in 12/30 patients (40%), causing treatment discontinuation in three (10%). One patient (achieving CR) had a tyrosine kinase domain mutation (p.H1094Y), and all other patients had MET exon 14 skipping mutations.

Crizotinib is a valuable treatment option in METmut aNSCLC.

MET tyrosine kinase inhibitor (TKI) therapy is associated with improved outcomes in patients with nonsmall cell lung cancer (NSCLC) harboring a MET alteration, including MET exon 14 (METex14) skipping mutation, MET amplification, or MET fusion. However, primary or acquired resistance to TKI therapy ultimately develops. In preclinical models, hyperactivation of MAPK signaling was shown to promote resistance to MET TKI; resistance was overcome by co-treatment with a MET inhibitor and a MEK inhibitor. This phase I/Ib study offers a potential combination strategy simultaneously targeting MET (with capmatinib) and MEK signaling (with trametinib) to overcome resistance to MET inhibitor monotherapy in METex14 NSCLC.

In the dose escalation phase, a minimum of 6 and maximum of 18 patients will be enrolled using a conventional 3+3 design with the primary endpoint of identifying a recommended phase 2 dose (RP2D) of capmatinib in combination with trametinib. Once the RP2D is identified, patients will continue to enroll in a dose expansion phase to a total of 15 patients. The primary endpoint of the dose expansion phase is to further characterize the safety profile of the combination.

This phase I/Ib clinical trial will assess the safety and efficacy of combination capmatinib and trametinib in NSCLC patients whose tumors harbor METex14 skipping mutations, MET amplification, or MET fusion and had developed progressive disease on single agent MET inhibitor therapy.

Matching patients to an effective targeted therapy or immunotherapy is a challenge for advanced and metastatic non-small cell lung cancer (NSCLC), especially when relying on assays that test one marker at a time. Unlike traditional single marker tests, comprehensive genomic profiling (CGP) can simultaneously assess NSCLC tumors for hundreds of genomic biomarkers and markers for immunotherapy response, leading to quicker and more precise matches to therapeutics.

In this study, we performed CGP on 7,606 patients with advanced or metastatic NSCLC using the Illumina TruSight Oncology 500 (TSO 500) CGP assay to show its coverage and utility in detecting known and novel features of NSCLC.

Testing revealed distinct genomic profiles of lung adenocarcinoma and squamous cell carcinomas and detected variants with a current targeted therapy or clinical trial in >72% of patient tumors. Known associations between genomic alterations and immunotherapy markers were observed including significantly lower TMB levels in tumors with therapy-associated alterations and significantly higher PD-L1 levels in tumors with ALK, MET, BRAF, or ROS1 driver mutations. Co-occurrence analysis followed by network analysis with gene module detection revealed known and novel co-occurrences between genomic alterations. Further, certain modules of genes with co-occurring genomic alterations had dose-dependent relationships with histology and increasing or decreasing levels of PD-L1 and TMB, suggesting a complex relationship between PD-L1, TMB, and genomic alterations in these gene modules.

This study is the largest clinical study to date utilizing the TSO 500. It provides an opportunity to further characterize the landscape of NSCLC using this newer technology and show its clinical utility in detecting known and novel facets of NSCLC to inform treatment decision-making.

Mesenchymal epithelial transition factor (MET) variant is an independent prognostic factor for worse prognosis in patients with lung cancer or gastroesophageal adenocarcinoma. MET gene variants can be regarded as a subtype of melanoma but there is a lack of studies regarding the frequency of MET genetic alterations and the efficacy of immunotherapy in melanoma patients. The purpose of this study is to explore potential therapeutic strategies for melanoma subtypes with MET alterations.

A total of 1751 malignant melanomas were analyzed to illustrate the landscape of MET mutations. We collected 55 melanoma cases from multicenter for a retrospective cohort from 2010 to 2023. We analyzed the impact of MET amplification on the efficacy of immunotherapy in the retrospective cohort after propensity score matching (PSM) and a pancancer cohort. CIBERSORT was used to evaluate the immune infiltration.

There were no instances of MET 14 exon skipping, and only instances of MET amplification were found in the 1751 melanomas and our retrospective cohort. Cox proportional hazards model analysis showed that MET amplification (P = 0.006) was significantly associated with poorer overall survival (OS) in patients who received immunotherapy as the first-line treatment. Compared with patients with MET amplification, patients in the negative control (NC) group had a significantly better OS (P = 0.022) after PSM. Analysis of 1661 pancancer cases with the MSK-IMPACT assay showed that patients receiving immunotherapy in the MET amplification group had a trend toward worse OS than those without MET amplification (P = 0.025).

This database analysis showed that the main type of MET mutation is amplification in malignant melanoma. MET-amplified solid tumors might be considered for targeted therapy, as MET amplification can be regarded as a risk factor affecting the prognosis of patients with tumors treated with immunotherapy.

The clinical application of small molecule tyrosine kinase inhibitors (TKIs) has significantly improved the quality of life and prognosis of patients with non-small cell lung cancer (NSCLC) carrying driver genes. However, resistance to TKI treatment is inevitable. Bypass signal activation is one of the important reasons for TKI resistance. Although TKI drugs inhibit downstream signaling pathways of driver genes, key signaling pathways within tumor cells can still be persistently activated through bypass routes such as MET gene amplification, EGFR gene amplification, and AXL activation. This continuous activation maintains tumor cell growth and proliferation, leading to TKI resistance. The fundamental strategy to treat TKI resistance mediated by bypass activation involves simultaneously inhibiting the activated bypass signals and the original driver gene signaling pathways. Some clinical trials based on this combined treatment approach have yielded promising preliminary results, offering more treatment options for NSCLC patients with TKI resistance. Additionally, early identification of resistance mechanisms through liquid biopsy, personalized targeted therapy against these mechanisms, and preemptive targeting of drug-tolerant persistent cells may provide NSCLC patients with more sustained and effective treatment.

Adenoid cystic carcinoma (AdCC) of the head and neck harbors MYB/MYBL1::NFIB fusions in around 60% of cases, with unfavorable long-term survival due to frequent recurrences and metastases, currently lacking effective targeted therapy. The study aims to identify actionable alterations and to elucidate the molecular underpinnings of MYB/MYBL1::NFIB-negative AdCC using a large targeted RNA sequencing panel.

We retrospectively searched our MSK-Solid Fusion clinical sequencing database for head and neck AdCC sequenced between 2016 and 2023. Of a total of 55 cases, 28 showed MYB::NFIB, 7 showed MYBL1::NFIB, and one case each harbored MYB::MPDZ (case 1) and FUS::MYB (case 2). One base of tongue tumor expressed both MYB::NFIB fusion and MET exon 14 skipping transcripts due to concurrent MET splice site mutation, D1010N (case 3). One parotid tumor lacked MYB/MYBL1 rearrangement but instead showed an in-frame SEC16A::NOTCH1 fusion that preserved the secretase cleavage site (case 4). Clinical records on 4 cases with non-canonical sequencing findings were reviewed. Distant metastases were present at the initial diagnosis (case 2) or at recurrence (cases 1, 3, and 4). Disease-related mortality occurred in cases 2 and 4 despite radiotherapy and immunotherapy.

The study improved the understanding of AdCC providing the first documentation of tumor clinical behavior associated with MYB::MPDZ and FUS::MYB fusions and reporting potentially actionable SEC16A::NOTCH1 fusion and MET exon 14 skipping mutation. Further research is needed to explore the therapeutic utility of MET inhibition and the efficacy of γ-secretase inhibitors against rare NOTCH1 fusions in AdCC.

We established a method based on ultra performance liquid chromatography tandem mass spectrometry (UPLC‒MS/MS) to quantitatively measure tepotinib, which was validated as acceptable and used in the evaluation of food-drug interactions between tepotinib and naringenin in rats. We used pemigatinib as the internal standard (IS), and acetonitrile and 0.1% formic acid aqueous solution constituted the mobile phase. To extract the target analyte, acetonitrile was used for protein precipitation (PPT). For UPLC‒MS/MS, we performed liquid chromatography using a C18 column, and mass spectrometry was performed in positive multiple reaction monitoring (MRM) mode. Excellent linearity was shown in the range of 0.1-500 ng/mL, and the coefficient of correlation was > 0.99. Notably, the lower limit of quantification (LLOQ) for tepotinib was determined to be 0.1 ng/mL. The intra- and inter-day accuracy of tepotinib ranged from - 1.7 to 7.3%, while the precision was ≤ 8.4%, at three concentrations except LLOQ. The recovery of each substance was ≥ 81.2%, and the matrix effects were within 90.5-98.6%. The stabilities of all analytes under different conditions met all requirements for quantitation in plasma samples. The relevant parameters, such as LLOQ, were evaluated in accordance with the principles of the Food and Drug Administration (FDA) biological verification method. Food-drug interaction study had shown that the plasma concentration of tepotinib could be significantly increased, accompanied by a decrease in clearance rate when administered with 50 mg/kg naringenin. The results showed that naringenin could increase the plasma concentration and decrease the clearance rate of tepotinib when naringenin and tepotinib were administered at the same time.

The MET receptor, commonly known as HGF (hepatocyte growth factor) receptor, is a focus of extensive scientific research. MET has been linked to embryonic development, tissue regeneration following injury, tumorigenesis, and cancer metastasis. These functions underscore its involvement in numerous cellular processes, including stemness, proliferation, motility, cell dissociation, and survival. However, the enigmatic nature of MET becomes apparent in the context of cancer. When MET remains persistently activated, since its gene undergoes genetic alterations, it initiates a complex signaling cascade setting in motion an aggressive and metastatic program that is characteristic of malignant cells and is known as "invasive growth". The expanding knowledge of MET signaling has opened up numerous opportunities for therapeutic interventions, particularly in the realm of oncology. Targeting MET presents a promising strategy for developing novel anti-cancer treatments. In this review, we provide an updated overview of drugs designed to modulate MET signaling, highlighting MET kinase inhibitors, degraders, anti-MET/HGF monoclonal antibodies, and MET-targeted antibody-drug conjugates. Through this review, we aim to contribute to the ongoing advancement of therapeutic strategies targeting MET signaling.

Until the early 2000s, advanced or metastatic non-small cell lung cancer (NSCLC) was treated as a single disease with all histologic subtypes treated alike with standard chemotherapy agents. Over the past two decades, the treatment paradigms for advanced NSCLC have changed dramatically with the discovery of multiple targeted therapies that are now approved for the treatment of NSCLC tumors with specific oncogene drivers or molecular alterations. Molecular testing has become integrated and critical for the clinical management of advanced NSCLC. The discovery and success of these targeted therapies have reshaped the classification of NSCLC on the basis of molecular classification and enabled a personalized approach in thoracic oncology. In this review, we discuss recent developments in the molecular profiling of NSCLC, and approved and emerging targeted therapies for the treatment of NSCLC.

Non-small cell lung cancer (NSCLC), the leading cause of cancer-related mortality worldwide, poses a formidable challenge due to its heterogeneity and the emergence of resistance to targeted therapies. While initially effective, first- and third-generation EGFR-tyrosine kinase inhibitors (TKIs) often fail to control disease progression, leaving patients with limited treatment options. To address this unmet medical need, we explored the therapeutic potential of multitargeting agents that simultaneously inhibit two key signalling pathways, the mesenchymal-epithelial transition factor (c-MET) and the G protein-coupled receptor Smoothened (SMO), frequently dysregulated in NSCLC. By employing a combination of in silico drug repurposing and structure-based structure-activity relationship (SAR) studies, we identified and developed novel c-MET/SMO-targeting agents with antiproliferative activity against first- as well as third-generation EGFR-TKI-resistant NSCLC cells suggesting a synergistic effect arising from the simultaneous inhibition of c-MET and SMO.

MET exon 14 skipping alterations (METex14+) represent a heterogeneous subgroup of non-small cell lung cancer (NSCLC) with distinct biological and genomic features. We characterized this heterogeneity in a large cohort, integrating genomic and transcriptomic profiling with clinical outcomes, to elucidate the histologic and molecular traits and survival patterns of METex14+ NSCLC.

NSCLC tissue samples (n = 28,739) underwent DNA-based next-generation sequencing (592 genes, NextSeq) or whole-exome sequencing (NovaSeq), RNA-sequencing including whole transcriptome sequencing (WTS, NovaSeq), and PD-L1 IHC (Dako 22C3) at Caris Life Sciences. Immune cell fractions were estimated from bulk RNA sequencing (quanTIseq). Real-world survival data (mOS) was calculated from insurance claims. Statistical analyses employed Chi-square, Fisher's exact, or Mann-Whitney U and log-rank tests and were corrected for hypothesis testing where applicable.

A total of 711 METex14+ cases were detected. Of 575 cases of defined histology, 77 (13.6 %) were squamous (Sq), 474 (82.3 %) were nSq (non-squamous), and 24 (4.1 %) were adenosquamous. Mutations in POT1 and BRCA2 were enriched, and amplifications in MDM2, HMGA2, CDK4, and MET were common in METex14+ tumors. TMB-high and TP53 mutated tumors were reduced in METex14+ independent of histology. KEAP1 (2.1 vs 14.7 %) and STK11 mutations (0.8 vs 17.1 %) were reduced only in METex14+ nSq (vs METex14+ Sq, q < 0.05). While the prevalence of PD-L1 high tumors was enriched in METex14+ independent of histology, T-cell inflamed tumors were enriched only in nSq METex14+. B-cells and CD8+ T-cells (1.07-1.43-fold) were enriched in nSq METex14+, and dendritic cells (0.32 fold) were reduced only in METex14+ Sq. METex14+ tumors had a modest improvement in mOS compared to METex14- tumors (mOS = 22.9 m vs 18.6 m, HR = 0.914, p = 0.04). Moreover, METex14+ tumors who received immunotherapy (IO) had a modest improvement in survival (mOS = 27.5 m vs 21.8 m; HR = 0.803, p = 0.03) compared to those who did not receive IO. METex14+ nSq tumors were associated with improved mOS compared to METex14+ Sq tumors (mOS = 27.7 vs 8.9 m, HR = 0.493, p < 0.0001).

METex14+ alterations are a heterogeneous subgroup of NSCLC. Our analysis reveals that METex14+ nSq exhibit improved survival compared to METex14+ Sq. The distinct genomic and transcriptomic variations across histologies warrant clinical consideration.

Capmatinib is a selective MET inhibitor with demonstrated efficacy in a phase II study of non-small cell lung cancer (NSCLC) patients harboring METex14 mutations. However, the real-world outcomes of capmatinib are largely unknown. From June 2019, the French Early Access Program (EAP) provided capmatinib to METex14 NSCLC patients who were ineligible for or for whom first-line standard therapies had failed.

IFCT-2104 CAPMATU was a multicenter study that included all METex14 NSCLC patients who received capmatinib as part of the EAP until August 2021. The primary endpoints were time to treatment failure (TTF), progression-free survival (PFS), overall survival (OS) and objective response rate (ORR).

A total of 146 patients were included. The median age was 74.9 years, 56.6 % were never-smokers, and 32.4 % had brain metastases. The median TTF, median PFS and median OS from capmatinib initiation were 5.1 months (95 % CI 4.2-6.0), 4.8 months (95 % CI 4.0-6.0) and 10.4 months (95 % CI 8.3-13.2), respectively. Evaluation of the best response to capmatinib was available for 134 patients and resulted in an ORR of 55.3 % (95 % CI 46.8 %-63.6 %). The median PFS was 7.7 months for treatment-naïve patients and 6.0 and 4.1 months for patients who had received one or 2 + prior lines of treatment, respectively. For patients with brain metastases, the median PFS was 3.0 months. Capmatinib had a known and manageable safety profile, with grade 3 to 4 adverse events, mostly peripheral edema (8.2 %), occurring in 17.8 % of patients.

In this large real-world study of METex14 NSCLC patients, the efficacy of capmatinib was confirmed, with a manageable safety profile, even in patients with brain metastases and in those who received several lines of treatment. This study reinforces the key role of capmatinib for these patients.

Lung cancer is a leading cause of cancer-related deaths globally, and traditional chemotherapy has limited efficacy in treating advanced non-small cell lung cancer (NSCLC). In recent years, the prognosis for patients with NSCLC has significantly improved due to the development of new treatment modalities, including targeted therapies. Targeted therapies utilize monoclonal antibodies (mAbs), antibody-drug conjugates (ADCs), or small molecule tyrosine kinase inhibitors (TKIs) directed against specific mutated genes such as EGFR and ALK. The development of these drugs has deepened our understanding of NSCLC and improved treatment outcomes for patients. This review aims to summarize the mechanisms and current status of targeted therapy for NSCLC, discuss strategies to overcome acquired resistance, and address current challenges in the field.

MET is a receptor tyrosine kinase (RTK) responsible for initiating signaling pathways involved in development and wound repair. MET activation relies on ligand binding to the extracellular receptor, which prompts dimerization, intracellular phosphorylation, and recruitment of associated signaling proteins. Mutations, which are predominantly observed clinically in the intracellular juxtamembrane and kinase domains, can disrupt typical MET regulatory mechanisms. Understanding how juxtamembrane variants, such as exon 14 skipping (METΔEx14), and rare kinase domain mutations can increase signaling, often leading to cancer, remains a challenge. Here, we perform a parallel deep mutational scan (DMS) of the MET intracellular kinase domain in two fusion protein backgrounds: wild-type and METΔEx14. Our comparative approach has revealed a critical hydrophobic interaction between a juxtamembrane segment and the kinase ⍺C-helix, pointing to potential differences in regulatory mechanisms between MET and other RTKs. Additionally, we have uncovered a β5 motif that acts as a structural pivot for the kinase domain in MET and other TAM family of kinases. We also describe a number of previously unknown activating mutations, aiding the effort to annotate driver, passenger, and drug resistance mutations in the MET kinase domain.

Mesenchymal-epithelial transition (MET) exon 14 (METex14) skipping mutation is a rare alteration in non-small-cell lung cancer (NSCLC), occurring in about 3%-4% of cases. Here we report disease and patient characteristics, and efficacy and tolerability of MET inhibitors among advanced METex14 NSCLC patients from the Italian real-world registry ATLAS.

Clinical-pathological and molecular data, and treatment efficacy/tolerability outcomes were retrospectively collected from the ATLAS registry.

From July 2020 to July 2023 a total of 146 METex14 advanced NSCLC patients were included across 27 Italian centers. Median age was 74 years, and most patients were male (52%), with an Eastern Cooperative Oncology Group performance status < 2 (72%) and adenocarcinoma subtype (83%). One hundred and twenty-five out of 146 (86%) patients received at least one line of systemic anticancer therapy. Fifty-six (38%) were treated with capmatinib and 34 (23%) with tepotinib. 29% and 52% of them received targeted treatment in the first and second line, respectively. In the cohort of patients treated with MET inhibitors, the response rate (RR) was 37% (33% in previously treated patients and 46% in treatment-naïve) with a disease control rate of 62%. With a median follow-up of 10.8 months, progression-free survival was 6.6 months [95% confidence interval (CI) 4.3-8.3 months] and overall survival was 10.7 months (95% CI 7.2-19.3 months). In patients with measurable brain metastases (17 cases), the intracranial RR was 41%. Grade ≥3 treatment-related adverse events (TRAEs) occurred in 12% of patients with grade 3 peripheral edema in 7% of cases. A fatal adverse reaction occurred in one patient due to pneumonitis. TRAEs-related dose reduction and discontinuation were reported in 6% and 8% of cases, respectively.

Capmatinib and tepotinib represent an effective treatment option in NSCLC patients with METex14. Real-world efficacy outcomes are worse than those reported in prospective clinical trials. Their activity is more pronounced in the treatment-naïve population, suggesting that this is the right setting in the management of patients with METex14.