MET-dependent solid tumours - molecular diagnosis and targeted therapy

Biomarkers associated with papillary thyroid carcinoma and Hashimoto's thyroiditis: Bioinformatic analysis and experimental validation

PURPOSE

Hashimoto's thyroiditis (HT) is widely recognized as a risk factor for papillary thyroid carcinoma (PTC). This study aimed to identify key targets involved in the progression of HT to PTC.

METHODS

Microarray datasets (GSE138198) for PTC, HT, and PTC with HT in the background (PTC-W) were obtained from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were identified and analyzed between normal and diseased groups. Functional enrichment analysis was performed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Protein-protein interaction (PPI) network analysis was conducted to identify hub genes, which were validated through qPCR and immunohistochemical (IHC) analysis. ROC analysis was then carried out based on the expression levels of hub genes in clinical plasma samples.

RESULTS

A total of 78 shared DEGs were identified from the GEO dataset. GO and KEGG analyses highlighted pathways such as epithelial-to-mesenchymal transition (EMT) and PI3K-Akt signaling. The analysis of immune cell subtypes showed that the hub genes were commonly associated with various immune cells, particularly dendritic cells (DC) and macrophages. Ten hub genes-LYZ, FCER1G, CCL18, CXCL9, ALOX5, TYROBP, C1QB, CTSS, MET, and FAM20A-were identified from the PPI network. qPCR and IHC confirmed the overexpression of MET and FAM20A in PTC-W. The area under the curve (AUC) of the ROC analysis was 0.889 for MET and 0.825 for FAM20A.

CONCLUSION

This study identified two hub genes, MET and FAM20A, with potential diagnostic value in HT and PTC.

Exploration of efficacy of the first-line treatment for advanced non-small cell lung cancer with primary MET-amplification: Retrospective evaluation of 36 cases

BACKGROUND

There are few clinical data on targeted therapy for primary mesenchymal-epidermal transforming factor amplification (METamp), unlike METamp secondary to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs). First-line treatment options for patients with primary METamp NSCLC remain unclear, and in particular, the efficacy of immune checkpoint inhibitors (ICIs) in these patients is controversial.

METHODS

We retrospectively included primary METamp patients who had received at least one line of systemic anticancer therapy, diagnosed at Zhejiang Cancer Hospital from June 2018 to June 2023, and analyzed the efficacies of different treatment patterns for these patients. We also evaluated the potential relationship between the tumor immune microenvironment (TIME) and the programmed death-1 (PD-1)/programmed death ligand-1 (PD-L1) axis in primary METamp NSCLC patients. High-level METamp was defined as gene copy number (GCN) ≥ 10 [1]. The clinical outcomes included objective response rate (ORR), disease control rate (DCR), median progression-free survival (mPFS), median overall survival (mOS).

RESULTS

We screened 2016 NSCLC patients and detected 36 primary METamp, resulting in a prevalence of 1.79 %. Among the patients, the average MET GCN was 4.6, the overall ORR was 50.0 %, DCR was 77.8 %, mPFS was 5.8 months and mOS was 11.7 months. We categorized the first-line treatments that patients received as: immuno-chemotherapy (CI-group), antiangio-chemotherapy (CA-group), chemotherapy (C-group) and MET-TKIs therapy (TKI-group). The ORR of CI-group, CA-group, C-group and TKI-group was 64.3 %, 16.7 %, 33.4 % and 71.4 %, respectively. And the DCR of this four groups was 100 %, 50 %, 66.7 % and 71.4 %, respectively. CI-group achieved longer mPFS and mOS than other groups, respectively (mPFS: 8.63 vs 3.73 vs 3.53 vs 5.50 months, P = 0.021; mOS: 15.10 vs 11.73 vs 9.93 vs 13.93 months, P = 0.023). The mPFS was longer in the PD-L1-positive group than in the PD-L1 negative group (P = 0.046) and PD-L1 positivity was an independent prognostic indicator for PFS (P = 0.005). In addition, the disease remission effect was significantly lower in Foxp3-positive expressors than in negative expressors (ORR: 33.3 % vs 75.0 %, P = 0.024).

CONCLUSIONS

Immuno-chemotherapy is a first-line optional treatment strategy in addition to targeted therapy for NSCLC patients with primary METamp. Foxp3-negative expression better predicts the near-term efficacy of immunotherapy.

Clinical characteristics of EGFR-ctDNA shedders in EGFR-mutant NSCLC patients

BACKGROUND

Circulating tumor DNA (ctDNA) revolutionized the molecular diagnostics of lung cancer by enabling non-invasive, sensitive identification of actionable mutations. However, ctDNA analysis may be challenging due to tumor shedding variability, leading to false negative results. This study aims to understand the determinants for ctDNA shedding based on clinical characteristics of lung cancer patients, for a better interpretation of false negative results to be considered when ordering ctDNA analysis for clinical practice.

METHODS

Blood samples were collected from patients with stage IV EGFR-mutated (mEGFR) NSCLC before treatment and monitored until disease progression. EGFR was assessed on tissue by standard procedures, while EGFR status on ctDNA was tested using dPCR at baseline and at the first reassessment. NGS was used to evaluate patients mutational status at the progression of the disease.

RESULTS

A total of 40 mEGFR tissue samples were collected. Plasma samples were analyzed for mEGFR before starting the first line, 65 % of patients had detectable mEGFR in ctDNA ("shedders"). Higher ECOG PS (p = 0.04), bilateral localization of primary tumor (p = 0.04), and the presence of intrathoracic/extrathoracic disease (p = 0.05), were associated to mEGFR shedding. Shedders had shorter PFS compared to non-shedders (p = 0.03). Patients with detectable mEGFR in ctDNA at the first radiological assessment exhibited worse PFS compared to patients with ctDNA clearance (p = 0.05).

CONCLUSION

Our preliminary data demonstrate that specific clinical characteristics predict mEGFR shedding in ctDNA of NSCLC, suggesting a potential clinical applicability for understanding potential false negative results and appropriate reporting in clinical practice.

Programmable Circular Multispecific Aptamer-Drug Engager to Broadly Boost Antitumor Immunity

Safely and effectively harnessing innate immunity to boost cancer immunotherapy is promising yet challenging. Hence, we have developed a series of programmable aptamer-based multispecific engagers by encoding various artificial aptamer-drug codons with DNA-templated polymerization, aiming to broadly boost innate and adaptive immunity for antitumor therapy. All circular single-stranded multivalent aptamer-drug conjugates (os-mvApDCs) had a dendritic structure, precise size, and excellent stability, enabling prolonged blood circulation, targeted tumor accumulation, and rapid multireceptor-mediated endocytosis. A trispecific engager (Sl/Pd/Mjos-mvApDCsSMT), targeting PD-1 on CD8+ T cells and PD-L1/c-Met on tumor cells, recruited large amounts of immune cells into the tumor and released cytotoxic MMAE and immunomodulators, inducing severe cell death and broad activation of innate immunity. When combined with the αPD-1 blockade, there was a significant increase in the number of CD8+ T cells (10-fold increase versus untreated control) engaged and expanded in the tumor, exhibiting potent function (IFN-γ+/GzmB+) and low exhaustion (PD-1+TIM-3+). The orchestrated innate and adaptive immunity effectively eliminated immunosuppressive MDSCs, Tregs, and M2-like macrophages in tumors and promoted the maturation of dendritic cells (DCs) in the draining lymph nodes, resulting in robust and durable systemic antitumor efficacy, with 7 out of 8 mice surviving over 60 days. Our programmable DNA-templated printing technology enables the rational design of multispecific therapeutics with modular composition and function but minimal production issues, providing a versatile tool for the development of multifunctional personalized medicine.

Genomic characteristics of PD-L1-Induced resistance to EGFR-TKIs in lung adenocarcinoma

BACKGROUND

The co-occurrence of PD-L1 positivity and EGFR mutations in advanced NSCLC often limits EGFR-TKIs effectiveness, with unclear mechanisms.

METHODS

We analyzed 103 treatment-naive EGFR-mutant LUAD patients from three centers, assessing PD-L1 expression and performing NGS analysis.

RESULTS

SMO mutations and MET amplification were significantly higher in the PD-L1 ≥ 1% group versus PD-L1 < 1% group (SMO: 8% vs. 0%, p = 0.048; MET: 18% vs. 7%, p = 0.023). The DNA Damage Response and Repair (DDR) pathogenic deficiency mutations, along with biological processes and signaling pathways related to DNA recombination, cell cycle transition and abnormal phosphorylation, were more prevalent in the PD-L1 ≥ 1% group. PIK3CA and RARA clonal alterations were more common in PD-L1 < 1% group, while TP53 clonal mutations predominated in PD-L1 ≥ 1% group. Retrospective analysis showed EGFR-TKIs plus chemotherapy extended median PFS by 9.8 months, potentially overcoming EGFR-TKI monotherapy resistance.

CONCLUSION

This study elucidates the genomic characteristics of PD-L1-induced resistance to EGFR-TKIs. For patients with concurrent mutations in EGFR and PD-L1 expression, a first-line treatment strategy combining EGFR-TKIs with chemotherapy may offer a more effective alternative.

Exploring the Complexity of Pan-Cancer: Gene Convergences and in silico Analyses

Cancer is a complex and multifaceted group of diseases characterized by highly intricate mechanisms of tumorigenesis and tumor progression, which complicates diagnosis, prognosis, and treatment. In recent years, targeted therapies have gained prominence by focusing on specific mutations and molecular features unique to each tumor type, offering more effective and personalized treatment options. However, it is equally critical to explore the genetic commonalities across different types of cancer, which has led to the rise of pan-cancer studies. These approaches help identify shared therapeutic targets across various tumor types, enabling the development of broader and potentially more widely applicable treatment strategies. This review aims to provide a comprehensive overview of key concepts related to tumors, including tumorigenesis processes, the tumor microenvironment, and the role of extracellular vesicles in tumor biology. Additionally, we explore the molecular interactions and mechanisms driving tumor progression, with a particular focus on the pan-cancer perspective. To achieve this, we conducted an in silico analysis using publicly available datasets, which facilitated the identification of both common and divergent genetic and molecular patterns across different tumor types. By integrating these diverse areas, this review offers a clearer and deeper understanding of the factors influencing tumorigenesis and highlights potential therapeutic targets.

Precision medicine: an intrahepatic cholangiocarcinoma with a novel RBPMS-MET fusion sensitive to crizotinib

BACKGROUND

Intrahepatic cholangiocarcinoma is a malignant tumor that starts from the epithelium of the bile duct and has a poor prognosis. They are characterized by poor response to chemotherapy and lack of effective targeted therapies; thus, therapeutic options are limited.

CASE PRESENTATION

A 59-year-old man was admitted to the hospital for a workup of abnormal CA19-9 levels. He was diagnosed with ICC, underwent surgery and was found to have pT1bNx disease. He developed rapid disease recurrence on adjuvant gemcitabine + capecitabine. Following recurrence, he received first-line systemic pembrolizumab + lenvatinib and second-line pembrolizumab + lenvatinib + chemotherapy and had mild tumor regression followed by progression. Next-generation sequencing was performed on the baseline surgical sample. This revealed a novel RBPMS-MET fusion, and based on the literature, crizotinib 250 mg twice a day was administered. After 3 months of crizotinib treatment, magnetic resonance imaging revealed a significant reduction in liver lesions, and 4 months after initiating treatment, scans demonstrated a partial response.

CONCLUSION

Our case report strengthens the evidence that crizotinib may be a viable treatment option for patients with ICC with a c-MET tyrosine kinase fusion, necessitating additional clinical investigation.

Mechanisms of traditional Chinese medicine in the treatment and prevention of gastric cancer

BACKGROUND

Gastric cancer (GC) ranks as the fifth most prevalent malignancy worldwide. Conventional treatments, including radiotherapy and chemotherapy, often induce severe side effects and significant adverse reactions, and they may also result in drug resistance. Consequently, there is a critical need for the development of new therapeutic agents. Traditional Chinese Medicine (TCM) and natural products are being extensively researched due to their low toxicity, multi-targeted approaches, and diverse pathways. Scholars are increasingly focusing on identifying active anticancer components within TCM.

PURPOSE

This review aims to summarise research conducted over the past 14 years on the treatment of GC using TCM. The focus is on therapeutic targets, mechanisms, and efficacy of Chinese medicine and natural products, including monomer compounds, extracts or analogues, and active ingredients.

METHODS

Relevant articles on TCM and GC were retrieved from PubMed using appropriate keywords. The collected articles were screened and classified according to the types of TCM, with an emphasis on the molecular mechanisms underlying the treatment of GC.

RESULTS

The research on TCM indicates that TCM and natural products can effectively inhibit the metastasis, proliferation, and invasion of tumour cells. They can also induce apoptosis, autophagy and improve the chemosensitivity of drug-resistant cells. Additionally, injections derived from Chinese herbal medicine, when used as an adjunct to conventional chemotherapy, can significantly improve the prognosis of GC patients by reducing chemotherapy toxicity.

CONCLUSION

This review summarises the progress of TCM treatment of GC over the past 14 years, and discusses its therapeutic application of GC, which proves that TCM is a promising treatment strategy for GC in the future.

Multicenter Real-World Analysis of Combined MET and EGFR Inhibition in Patients With Non-Small Cell Lung Cancer and Acquired MET Amplification or Polysomy After EGFR Inhibition

PURPOSE

MET amplification is a common resistance mechanism to EGFR inhibition in EGFR-mutant non-small cell lung cancer (NSCLC). Several trials showed encouraging results with combined EGFR and MET inhibition (EGFRi/METi). However, MET amplification has been inconsistently defined and frequently included both polysomy and true amplification.

METHODS

This is a multicenter, real-world analysis in patients with disease progression on EGFR inhibition and MET copy number gain (CNG), defined as either true amplification (MET to centromere of chromosome 7 ratio [MET-CEP7] ≥ 2) or polysomy (gene copy number ≥ 5, MET-CEP7 < 2).

RESULTS

A total of 43 patients with MET CNG were included, 42 of whom were detected by FISH. Twenty-three, 7, and 14 received EGFRi/METi, METi, and SoC, respectively. Patients in the EGFRi/METi cohort exhibited a superior real-world clinical benefit rate, defined as stable disease or better, of 82% (95% confidence interval [CI], 60-95) compared to METi (29%, 4-71) and SoC (50%, 23-77). Median real-world progression-free survival was longer with EGFRi/METi with 9.8 vs. 4.3 months with METi (hazard ratio [HR], 0.19, 95% CI, 0.06-0.57) and 3.7 months with SoC (0.41, 0.18-0.91), respectively. Overall survival was numerically improved. Interaction analysis with treatment and type of CNG (amplification vs. polysomy) suggests that differences were exclusively driven by MET-amplified patients receiving EGFRi/METi (HR for OS, 0.09, 0.01-0.54).

CONCLUSION

In this real-world study, EGFRi/METi showed clinical benefit over METi and SoC. Future studies should focus on the differential impact of the type of MET CNG with a focus on true MET amplification as predictor of response.

Fluorescence based live cell imaging identifies exon 14 skipped hepatocyte growth factor receptor (MET) degraders

Despite ongoing efforts to employ structure-based methods to discover targeted protein degraders (TPD), the prevailing strategy continues to be the synthesis of a focused set of heterobifunctional compounds and screen them for target protein degradation. Here we used a fluorescence based live cell imaging screen to identify degraders that target exon 14 skipped hepatocyte growth factor receptor (MET). MET is a known oncogenic driver. MET exon 14 skipping mutations (METex14Δ) are found in lung cancers and result in the loss of a degron that is required for E3-ligase recognition and subsequent ubiquitination, prolonging the half-life and oncogenicity of MET. Since proteolysis targeting chimeras (PROTACs) are heterobifunctional molecules that promote target degradation by the proteosome, we sought to restore degradation of MET lost with METex14Δ using a MET-targeting PROTAC. We generated a library of sixty PROTACs of which 37 used the MET inhibitor capmatinib as the protein of interest targeting ligand. We screened this PROTAC library for targeted degradation of METex14Δ-GFP using live cell imaging. We benchmarked out MET-targeting PROTACs to that of a previously reported MET-targeting PROTAC, SJF8240. Curve fitting live cell imaging data affords determination of time required to degrade 50% of the target protein (DT50), which was used in determining structure activity relationships. A promising candidate, 48-284, identified from the screen, exhibited classic PROTAC characteristics, was > 15-fold more potent than SJF8240, had fewer off targets compared to SJF8240, and degraded MET in multiple cell lines.

MET amplification correlates with poor prognosis and immunotherapy response as a subtype of melanoma: a multicenter retrospective study

BACKGROUND

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.

METHODS

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.

RESULTS

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).

CONCLUSIONS

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.

Comparison of Results from Two Commercially Available In-House Tissue-Based Comprehensive Genomic Profiling Solutions: Research Use Only AVENIO Tumor Tissue Comprehensive Genomic Profiling Kit and TruSight Oncology 500 Assay

Increased adoption of personalized medicine has brought comprehensive genomic profiling (CGP) to the forefront. However, differences in assay, bioinformatics, and reporting systems and lack of understanding of their complex interplay are a challenge for implementation and achieving uniformity in CGP testing. Two commercially available, tissue-based, in-house CGP assays were compared, in combination with a tertiary analysis solution in a research use only (RUO) context: the AVENIO Tumor Tissue CGP RUO Kit paired with navify Mutation Profiler (RUO) software and the TruSight Oncology 500 RUO assay paired with PierianDx Clinical Genomics Workspace software. Agreements and differences between the assays were assessed for short variants, copy number alterations, rearrangements, tumor mutational burden, and microsatellite instability, including variant categorization and clinical trial-matching (CTM) recommendations. Results showed good overall agreement for short variant, known gene fusion, and microsatellite instability detection. Important differences were obtained in tumor mutational burden scoring, copy number alteration detection, and CTM. Differences in variant and biomarker detection could be explained by bioinformatic approaches to variant calling, filtering, tiering, and normalization; differences in CTM, by underlying reported variants and conceptual differences in system parameters. Thus, distinctions between different approaches may lead to inconsistent results. Complexities in calling, filtering, and interpreting variants illustrate key considerations for implementation of any high-quality CGP in the laboratory and bringing uniformity to genomic insight results.

Comprehensive liquid biopsy analysis for monitoring NSCLC patients under second-line osimertinib treatment

Background

The heterogeneous and complex genetic landscape of NSCLC impacts the clinical outcomes of patients who will eventually develop resistance to osimertinib. Liquid biopsy (LB) analysis as a minimally invasive approach is a key step to efficiently identify resistance mechanisms and adjust to proper subsequent treatments.

Materials and methods

In the present study, we combined plasma-cfDNA and CTC analysis from 30 NSCLC patients in samples collected before treatment and at the progression of disease (PD). We detected molecular alterations at the DNA mutation (EGFR, PIK3CA, KRAS G12C, BRAF V600E), DNA methylation (RASSF1A, BRMS1, FOXA1, SLFN1, SHISA3, RARβ,, WIF-1, RASSF10 and APC), gene expression (CK-19, CK-18, CK-8, AXL, TWIST-1, PD-L1, PIM-1, Vimentin, ALDH-1, and B2M) and chromosomal level (HER2 and MET amplification) as possible resistance mechanisms and druggable targets. We also studied the expression of PD-L1 in single CTCs using immunofluorescence.

Results

In some cases, T790M resistance EGFR mutation was detected at baseline in CTCs but not in the corresponding plasma cfDNA. PIK3CA mutations were detected only in plasma-cfDNA but not in corresponding CTCs. KRAS G12C and BRAF V600E mutations were not detected in the samples analyzed. MET amplification was detected in the CTCs of two patients before treatment whereas HER2 amplification was detected in the CTCs of three patients at baseline and in one patient at PD. DNA methylation analysis revealed low concordance between CTCs and cfDNA, indicating the complementary information obtained through parallel LB analysis. Results from gene expression analysis indicated high rates of vimentin-positive CTCs detected at all time points during osimertinib. Moreover, there was an increased number of NSCLC patients at PD harboring CTCs positive in PD-L1. AXL and PIM-1 expression detected in CTCs during treatment suggesting new possible therapeutic strategies.

Discussion

Our results reveal that comprehensive liquid biopsy analysis can efficiently represent the heterogeneous molecular landscape and provide prominent information on subsequent treatments for NSCLC patients at PD since druggable molecular alterations were detected in CTCs.

Anti-MET Antibody Therapies in Non-Small-Cell Lung Cancer: Current Progress and Future Directions

Background/Objectives: Non-small-cell lung cancer (NSCLC) remains a leading cause of cancer mortality globally, though advances in targeted therapies have improved treatment outcomes. The mesenchymal-epithelial transition (MET) gene plays a significant role in NSCLC, often through protein overexpression, exon 14 skipping mutations, and gene amplification, many of which arise as resistance mechanisms to other oncogenic drivers like epidermal growth factor receptor (EGFR) mutations. This review examines the development and clinical efficacy of anti-MET antibody therapies. Methods: A comprehensive literature search was conducted using major medical databases looking at key relevant studies on anti-MET antibody studies. Both authors reviewed the literature, assessed study quality, and interpreted the results from each study. Results: Amivantamab, a bispecific EGFR/MET antibody was approved to treat EGFR exon 20 insertion and now has recently been extended to target classical EGFR mutations with progression on osimertinib. Other important anti-MET targeted therapies in development include antibody drug conjugates such as telisotuzumab vedotin, REGN5093-M114, and AZD9592 and emibetuzumab, which is a humanized immunoglobulin G4 monoclonal bivalent MET antibody. Conclusions: MET plays a significant role in NSCLC and amivantamab along with other anti-MET targeted therapies play a role in directly targeting MET and addressing acquired resistance to oncogenic drivers. Future research should focus on developing novel MET antibody drugs and exploring new therapeutic combinations to enhance treatment efficacy and overcome resistance in NSCLC. Refining biomarker-driven approaches to ensure precise patient selection is also critical to optimizing treatment outcomes.

Selective and Orally Bioavailable c-Met PROTACs for the Treatment of c-Met-Addicted Cancer

c-Met is an attractive therapeutic target in multiple tumors. Previous studies have discovered some effective proteolysis-targeting chimeras (PROTACs) able to degrade c-Met; however, the structure-activity relationship (SAR), degradation selectivity, and pharmacokinetic profiles of c-Met PROTACs have, to date, remained largely unknown. Herein, through extensive SAR studies on various warheads, linkers, and E3 ligase ligands, a novel potent c-Met PROTAC Met-DD4 was identified. Our results suggested that Met-DD4 could induce robust c-Met degradation with excellent selectivity (DC50 = 6.21 nM), substantially killing the c-Met-addicted cancer cells (IC50 = 4.37 nM). Furthermore, in vivo studies showed that Met-DD4 could achieve excellent oral bioavailability and c-Met degradation, strongly retarding tumor growth with minute organ toxicity. Overall, this study reveals that targeted degradation of c-Met is a promising strategy for the treatment of c-Met-addicted cancers and provides novel lead compounds for the clinical translation of c-Met PROTACs.

Diversified applications of hepatocellular carcinoma medications: molecular-targeted, immunotherapeutic, and combined approaches

Hepatocellular carcinoma (HCC) is one of the primary forms of liver cancer and is currently the sixth most prevalent malignancy worldwide. In addition to surgical interventions, effective drug treatment is essential for treating HCC. With an increasing number of therapeutic drugs for liver cancer undergoing clinical studies, the therapeutic strategies for advanced HCC are more diverse than ever, leading to improved prospects for HCC patients. Molecular targeted drugs and immunotherapies have become crucial treatment options for HCC. Treatment programs include single-agent molecular-targeted drugs, immunotherapies, combinations of immunotherapies with molecular-targeted drugs, and dual immune checkpoint inhibitors. However, further exploration is necessary to determine the optimal pharmacological treatment regimens, and the development of new effective drugs is urgently needed. This review provides an overview of the current globally approved drugs for liver cancer, as well as the latest advances in ongoing clinical research and drug therapies. Additionally, the review offers an outlook and discussion on the prospects for the development of drug therapy approaches for HCC.

Single-Nucleus RNA-Sequencing Reveals a MET+ Oligodendrocyte Subpopulation That Promotes Proliferation of Radiation-Induced Gliomas

PURPOSE

Radiation-induced gliomas (RIGs) are fatal late complications of radiation therapy, with a median survival time of 6 to 11 months. RIGs demonstrate a unique molecular landscape and may originate from a glial lineage distinct from that of primary malignancies or diffuse midline gliomas (DMGs). This study aimed to explore the intratumoral diversity within RIGs to uncover their cellular origin and characteristics and enhance our understanding of this uncommon tumor type.

METHODS AND MATERIALS

Formalin-fixed, paraffin-embedded samples were collected from 2 RIGs and 2 DMGs for single-nucleus RNA sequencing. A detailed analysis was conducted to assess intratumoral heterogeneity and cellular interactions, including gene set enrichment, pseudotime trajectory, and cell communication analyses. Immunofluorescence staining, proliferation assay, and RNA-seq analysis were also applied to validate our findings.

RESULTS

Our analysis revealed distinct heterogeneity in oligodendrocytes (ODs) between the DMG and RIG samples. A unique subpopulation of ODs in RIGs, which was characterized by gene encoding mesenchymal-epithelial transition factor (MET), and therefore termed MET+ ODs, exhibited characteristics typical of cancer cells, such as increased mitotic activity, cancer-related gene expression, and extensive copy number variations. Cell communication studies indicated that MET+ ODs interact vigorously with G1/S and G2/M cycling cells via the neural cell adhesion molecule signaling pathway, potentially enhancing the proliferation of cycling malignant cells. Integrating our results with existing RNA-seq data further supported our hypothesis. The presence of MET+ ODs in RIGs was confirmed by immunostaining, and activation of the neural cell adhesion molecule signaling pathway in vitro significantly promoted the proliferation of RIG tumor cells. Moreover, in vitro radiation induced the transformation of ODs to be more similar to MET+ ODs.

CONCLUSIONS

RIGs are characterized by an OD composition distinct from that of DMGs. A specific subpopulation of MET+ ODs in RIGs may be crucial in tumorigenesis and promote the growth of malignant cells. Identifying MET+ ODs offers a valuable target for future clinical surveillance and therapeutic strategies.

A Bispecific Chimeric Aptamer Design Platform Based on c-MET Aptamer with a Replaceable Redundant Region

Molecular engineering enables the creation of aptamers with novel functions, but the prerequisite is a deep understanding of their structure and recognition mechanism. The cellular-mesenchymal epithelial transition factor (c-MET) is garnering significant attention due to the critical role of the c-MET/HGF signaling pathway in tumor development and invasion. This study reports a strategy for constructing novel chimeric aptamers that bind to both c-MET and other specific proteins. c-MET was identified to be the molecular target of a DNA aptamer, HF3-58, selected through cell-SELEX. The binding structure and mechanism of HF3-58 with c-MET were systematically studied, revealing the scaffold, recognition, and redundancy regions. Through molecular engineering design, the redundancy region was replaced with other aptamers possessing stem-loop structures, yielding novel chimeric aptamers with bispecificity for binding to c-MET and specific proteins. A chimeric bispecific aptamer HF-3b showed the ability to mediate the adhesion of T-cells to tumor cells, suggesting the prospective utility in tumor immunotherapy. These findings suggest that aptamer HF3-58 can serve as a molecular engineering platform for the development of diverse multifunctional ligands targeting c-MET. Moreover, comprehensive understanding of the binding mechanisms of aptamers will provide guidance for the design of functional aptamers, significantly expanding their potential applications.

A phase II study of tepotinib in patients with advanced solid cancers harboring MET exon 14 skipping mutations or amplification (KCSG AL19-17)

BACKGROUND

We evaluated the efficacy and safety of tepotinib in patients with various solid cancers harboring MET exon 14 skipping mutation (METex14) or MET gene amplification.

PATIENTS AND METHODS

A phase II, multicenter study was conducted in patients with advanced or metastatic solid cancers who progressed after standard treatment, harboring either METex14 or MET amplification detected in tissue-based next-generation sequencing (NGS). The primary endpoint was objective response rate (ORR). For exploratory analyses, we analyzed the gene profiles using plasma NGS test.

RESULTS

Thirty-five patients were enrolled. The ORR was 57.6% for all patients, 52.2% for those with METex14, and 70% for those with MET amplification. Median progression-free survival (PFS) was 8 months [95% confidence interval (CI) 4.5-11.5 months] and median overall survival (OS) was 14 months (95% CI 7.8-20.2 months) in all patients. For patients with non-small-cell lung cancer with METex14, the median PFS was 9 months (95% CI 4.7-13.4 months) and the median OS was 17 months [95% CI not applicable (NA)-NA]. For patients with MET amplification, the median PFS was 7 months (95% CI 1.5-12.5 months) and the median OS was 10 months (95% CI 5.8-14.2 months). The ORR of patients with MET dysregulation detected by plasma NGS was 72.2%, whereas the ORR was 30% in those without detection. The most common adverse events were peripheral edema, asthenia, transaminase elevation, and anorexia, mostly grade 1 or 2.

CONCLUSIONS

Tepotinib demonstrated consistent antitumor activity in patients with METex14, and promising antitumor activity in various cancers with MET amplification. Detection of MET dysregulation by plasma NGS may predict the response to tepotinib.

DNA/RNA-based electrochemical nanobiosensors for early detection of cancers

Nucleic acids, like DNA and RNA, serve as versatile recognition elements in electrochemical biosensors, demonstrating notable efficacy in detecting various cancer biomarkers with high sensitivity and selectivity. These biosensors offer advantages such as cost-effectiveness, rapid response, ease of operation, and minimal sample preparation. This review provides a comprehensive overview of recent developments in nucleic acid-based electrochemical biosensors for cancer diagnosis, comparing them with antibody-based counterparts. Specific examples targeting key cancer biomarkers, including prostate-specific antigen, microRNA-21, and carcinoembryonic antigen, are highlighted. The discussion delves into challenges and limitations, encompassing stability, reproducibility, interference, and standardization issues. The review suggests future research directions, exploring new nucleic acid recognition elements, innovative transducer materials and designs, novel signal amplification strategies, and integration with microfluidic devices or portable instruments. Evaluating these biosensors in clinical settings using actual samples from cancer patients or healthy donors is emphasized. These sensors are sensitive and specific at detecting non-communicable and communicable disease biomarkers. DNA and RNA's self-assembly, programmability, catalytic activity, and dynamic behavior enable adaptable sensing platforms. They can increase biosensor biocompatibility, stability, signal transduction, and amplification with nanomaterials. In conclusion, nucleic acids-based electrochemical biosensors hold significant potential to enhance cancer detection and treatment through early and accurate diagnosis.

Savolitinib conferred sensitivity in a patient with D1228H mutation-induced capmatinib-resistant MET exon 14 skipping mutated lung adenocarcinoma

Traditionally, the D1228 E/G/H/N mutation has been thought to cause Type I MET-TKI resistance. We reported a 75-year-old female with non-small cell lung cancer harboring MET exon 14 skipping mutation, who developed acquired MET D1228H mutation induced by capmatinib treatment. Interestingly, the patient demonstrated marked response to second-line savolitinib treatment with the duration of response of 19 months and several additional metastatic lesions appeared. Pathological assessment of rebiopsy sample showed adenocarcinoma and targeted next-generation sequencing revealed the loss of MET D1228H mutation and presence of MET p.Y1230N mutation. In response, the treatment regimen was amended to include a daily administration of 60 mg of cabozantinib, which resulted in moderate size reduction of the tumours. The switch of resistance mutations indicated that different type Ib MET inhibitors may exhibit distinct mechanisms of resistance. We call for futher studies on resistance based on patient-derived pre-clinical models including patient-derived tumor-like cell clusters, patient-derived organoids, and patient-derived xenografts.

SexAnnoDB, a knowledgebase of sex-specific regulations from multi-omics data of human cancers

BACKGROUND

Sexual differences across molecular levels profoundly impact cancer biology and outcomes. Patient gender significantly influences drug responses, with divergent reactions between men and women to the same drugs. Despite databases on sex differences in human tissues, understanding regulations of sex disparities in cancer is limited. These resources lack detailed mechanistic studies on sex-biased molecules.

METHODS

In this study, we conducted a comprehensive examination of molecular distinctions and regulatory networks across 27 cancer types, delving into sex-biased effects. Our analyses encompassed sex-biased competitive endogenous RNA networks, regulatory networks involving sex-biased RNA binding protein-exon skipping events, sex-biased transcription factor-gene regulatory networks, as well as sex-biased expression quantitative trait loci, sex-biased expression quantitative trait methylation, sex-biased splicing quantitative trait loci, and the identification of sex-biased cancer therapeutic drug target genes. All findings from these analyses are accessible on SexAnnoDB ( https://ccsm.uth.edu/SexAnnoDB/ ).

RESULTS

From these analyses, we defined 126 cancer therapeutic target sex-associated genes. Among them, 9 genes showed sex-biased at both the mRNA and protein levels. Specifically, S100A9 was the target of five drugs, of which calcium has been approved by the FDA for the treatment of colon and rectal cancers. Transcription factor (TF)-gene regulatory network analysis suggested that four TFs in the SARC male group targeted S100A9 and upregulated the expression of S100A9 in these patients. Promoter region methylation status was only associated with S100A9 expression in KIRP female patients. Hypermethylation inhibited S100A9 expression and was responsible for the downregulation of S100A9 in these female patients.

CONCLUSIONS

Comprehensive network and association analyses indicated that the sex differences at the transcriptome level were partially the result of corresponding sex-biased epigenetic and genetic molecules. Overall, SexAnnoDB offers a discipline-specific search platform that could potentially assist basic experimental researchers or physicians in developing personalized treatment plans.

A pooled analysis of clinical outcome in driver-gene negative non-small cell lung cancer patients with MET overexpression treated with gumarontinib

Background

MET overexpression represents the most MET aberration in advanced non-small-cell lung cancer (NSCLC). However, except MET exon 14 (METex14) skipping mutation was recognized as a clinical biomarker, the role of MET overexpression as a predictive factor to MET inhibitor is not clear.

Objectives

The purpose of the pooled analysis is to explore the safety and efficiency of gumarontinib, a highly selective oral MET inhibitor, in drive-gene negative NSCLC patients with MET overexpression.

Design and methods

NSCLC patients with MET overexpression [immunohistochemistry (IHC) ⩾3+ as determined by central laboratory] not carrying epidermal growth factor receptor mutation, METex14 skipping mutation or other known drive gene alternations who received Gumarontinib 300 mg QD from two single arm studies were selected and pooled for the analysis. The efficacy [objective response rate (ORR), disease control rate (DCR), duration of response, progression-free survival (PFS) and overall survival (OS)] and safety [treatment emergent adverse event (TEAE), treatment related AE (TRAE) and serious AE (SAE) were assessed.

Results

A total of 32 patients with MET overexpression were included in the analysis, including 12 treatment naïve patients who refused or were unsuitable for chemotherapy, and 20 pre-treated patients who received ⩾1 lines of prior systemic anti-tumour therapies. Overall, the ORR was 37.5% [95% confidence interval (CI): 21.1-56.3%], the DCR was 81.3% (95% CI: 63.6-92.8%), median PFS (mPFS) and median OS (mOS) were 6.9 month (95% CI: 3.6-9.7) and 17.0 month (95% CI: 10.3-not evaluable), respectively. The most common AEs were oedema (59.4%), hypoalbuminaemia (40.6%), alanine aminotransferase increased (31.3%).

Conclusion

Gumarontinib showed promising antitumour activity in driver-gene negative locally advanced or metastatic NSCLC patients with MET overexpression, which warranted a further clinical trial.

Trial registration

ClinicalTrials.gov identifier: NCT03457532; NCT04270591.

NGS and FISH for MET amplification detection in EGFR TKI resistant non-small cell lung cancer (NSCLC) patients: A prospective, multicenter study in China

OBJECTIVES

Comprehensive data using Next-Generation Sequence (NGS) and fluorescence in situ hybridization (FISH) for detecting MET amplification is limited in Chinese patients, we evaluating NGS performance both in tissue and plasma samples using FISH as reference. We also sought to find optimal thresholds value for NGS in detecting MET amplification via bioinformatics methods.

METHOD

Patients progressed after 1st-, 2nd-, or 3rd-generation (G) EGFR-TKIs were enrolled. Tissue biopsy samples were performed for MET amplification detection via both NGS and FISH. Paired plasma samples were collected for MET amplification detection by NGS. The sensitivity, specificity and agreement were analyzed between NGS and FISH.

RESULTS

116 eligible patients were analyzed. 44 patients were male. 82 patients were after 3rd generation EGFR-TKI. MET amplification was detected in 43 (37.1 %) patients by FISH, including 19 (16.4 %) polysomy and 24 (20.7 %) focal amplification. The positive rate of MET amplification in post 3rd generation EGFR-TKI and post 1st/2ndgeneration EGFR-TKI resistant patients was 42.7 % (35/82), and 23.5 % (8/34). The sensitivity, specificity and agreement of detecting MET amplification by NGS in tissue were 39.5 % (17/43), 98.6 % (72/73) and 76.7 % (89/116), respectively, 66.7 % (16/24), 98.6 % (72/73) and 90.7 % (88/97) for focal MET amplification in tissue and 29.2 % (7/24), 94.5 % (69/73), 78.4 % (76/97) for focal amplification in plasma. Results were shown in the table below.

CONCLUSION

NGS is an alternative method for MET focal amplification detection in tissue. While the sensitivity of NGS testing in plasma needs further improvement to maximize identification of patients with potential benefit from dual-targeted therapy.

Overcoming Chemoresistance in Cancer: The Promise of Crizotinib

Chemoresistance is a major obstacle in cancer treatment, often leading to disease progression and poor outcomes. It arises through various mechanisms such as genetic mutations, drug efflux pumps, enhanced DNA repair, and changes in the tumor microenvironment. These processes allow cancer cells to survive despite chemotherapy, underscoring the need for new strategies to overcome resistance and improve treatment efficacy. Crizotinib, a first-generation multi-target kinase inhibitor, is approved by the FDA for the treatment of ALK-positive or ROS1-positive non-small cell lung cancer (NSCLC), refractory inflammatory (ALK)-positive myofibroblastic tumors (IMTs) and relapsed/refractory ALK-positive anaplastic large cell lymphoma (ALCL). Crizotinib exists in two enantiomeric forms: (R)-crizotinib and its mirror image, (S)-crizotinib. It is assumed that the R-isomer is responsible for the carrying out various processes reviewed here The S-isomer, on the other hand, shows a strong inhibition of MTH1, an enzyme important for DNA repair mechanisms. Studies have shown that crizotinib is an effective multi-kinase inhibitor targeting various kinases such as c-Met, native/T315I Bcr/Abl, and JAK2. Its mechanism of action involves the competitive inhibition of ATP binding and allosteric inhibition, particularly at Bcr/Abl. Crizotinib showed synergistic effects when combined with the poly ADP ribose polymerase inhibitor (PARP), especially in ovarian cancer harboring BRCA gene mutations. In addition, crizotinib targets a critical vulnerability in many p53-mutated cancers. Unlike its wild-type counterpart, the p53 mutant promotes cancer cell survival. Crizotinib can cause the degradation of the p53 mutant, sensitizing these cancer cells to DNA-damaging substances and triggering apoptosis. Interestingly, other reports demonstrated that crizotinib exhibits anti-bacterial activity, targeting Gram-positive bacteria. Also, it is active against drug-resistant strains. In summary, crizotinib exerts anti-tumor effects through several mechanisms, including the inhibition of kinases and the restoration of drug sensitivity. The potential of crizotinib in combination therapies is emphasized, particularly in cancers with a high prevalence of the p53 mutant, such as triple-negative breast cancer (TNBC) and high-grade serous ovarian cancer (HGSOC).

The Evolving Paradigm of Antibody-Drug Conjugates Targeting the ErbB/HER Family of Receptor Tyrosine Kinases

Current therapies targeting the human epidermal growth factor receptor (HER) family, including monoclonal antibodies (mAbs) and tyrosine kinase inhibitors (TKIs), are limited by drug resistance and systemic toxicities. Antibody-drug conjugates (ADCs) are one of the most rapidly expanding classes of anti-cancer therapeutics with 13 presently approved by the FDA. Importantly, ADCs represent a promising therapeutic option with the potential to overcome traditional HER-targeted therapy resistance by delivering highly potent cytotoxins specifically to HER-overexpressing cancer cells and exerting both mAb- and payload-mediated antitumor efficacy. The clinical utility of HER-targeted ADCs is exemplified by the immense success of HER2-targeted ADCs including trastuzumab emtansine and trastuzumab deruxtecan. Still, strategies to improve upon existing HER2-targeted ADCs as well as the development of ADCs against other HER family members, particularly EGFR and HER3, are of great interest. To date, no HER4-targeting ADCs have been reported. In this review, we extensively detail clinical-stage EGFR-, HER2-, and HER3-targeting monospecific ADCs as well as novel clinical and pre-clinical bispecific ADCs (bsADCs) directed against this receptor family. We close by discussing nascent trends in the development of HER-targeting ADCs, including novel ADC payloads and HER ligand-targeted ADCs.

Identification of diagnostic markers related to inflammatory response and cellular senescence in endometriosis using machine learning and in vitro experiment

OBJECTIVE

To understand the association between chronic inflammation, cellular senescence, and immunological infiltration in endometriosis.

METHODS

Datasets from GEO comprising 108 endometriosis and 97 healthy human samples and the human endometrial stromal cell. Differentially expressed genes were identified using Limma and WGCNA. Inflammatory response-related subtypes were constructed using consensus clustering analysis. The CIBERSORT algorithm and correlation analyses assessed immune cell infiltration. LASSO, SVM-RFE, and RF identified diagnostic genes. Functional enrichment analysis and multifactor regulatory networks established functional effects. Nomograms, internal and external validations, and in vitro experiments validated the diagnostic genes.

RESULTS

Inflammatory response subtypes were highly correlated with the immune activities of B and NK cells. Sixteen genes were associated with inflammatory response and cellular senescence and six diagnostic genes (NLK, RAD51, TIMELESS, TBX3, MET, and BTG3) were identified. The six diagnostic gene models had an area under the curve of 0.828 and their expression was significantly downregulated in endometriosis samples. Low expression of NLK and BTG3 promoted the proliferation, migration, and invasion of endometriotic cells.

CONCLUSIONS

Inflammatory response subtypes were successfully constructed for endometriosis. Six diagnostic genes related to inflammatory response and cellular senescence were identified and validated. Our study provides novel insights for inflammatory response in endometriosis and markers for endometriosis diagnosis and treatment.

Remarkable response to capmatinib in a patient with intrahepatic cholangiocarcinoma harboring TFG-MET fusion

Dysregulation of mesenchymal-epithelial transition factor (MET) gene due to amplification, mutation, and fusion has been reported in various types of human cancers. Recently, the efficacy of small-molecule tyrosine kinase inhibitors (TKIs) targeting MET has been demonstrated in a wide range of MET-dysregulated tumors. The majority of biliary tract cancers including intrahepatic cholangiocarcinoma (iCCA) are diagnosed at an advanced stage, and the utility of conventional chemotherapy is limited. Here, we present a case of metastatic iCCA harboring TFG-MET gene fusion, which demonstrated a remarkable response to treatment with capmatinib, a selective MET inhibitor. The patient was a 46-year-old man diagnosed with iCCA with hepatic, intraabdominal lymph nodes, and peritoneal metastases. Comprehensive genomic profiling (CGP) revealed TFG-MET gene fusion in his tumor. After becoming refractory to standard chemotherapy, he received capmatinib, which resulted in a marked shrinkage of the liver masses and lymph node metastases, as well as a drastic decrease in serum CA19-9 level. Our case reinforces the importance of CGP in exploring targeted therapy and supports the potential role of capmatinib in the treatment of tumors harboring MET fusions.

Synthesis and Evaluation of a Novel c-Met-Targeting Cyclic Peptide as a Potential Diagnostic Agent for Colorectal Cancer

The mesenchymal-epithelial transition factor (c-Met) is a receptor tyrosine kinase linked to the proliferation, survival, invasion, and metastasis of several types of cancers, including colorectal cancer (CRC), particularly when aberrantly activated. Our study strategically designs peptides derived from interactions between c-Met and the antibody Onartuzumab. By utilizing a cyclic strategy, we achieved significantly enhanced peptide stability and affinity. Our in vitro assessments confirmed that the cyclic peptide HYNIC-cycOn exhibited a higher affinity (KD = 83.5 nM) and greater specificity compared with its linear counterpart. Through in vivo experiments, [99mTc]Tc-HYNIC-cycOn displayed exceptional tumor-targeting capabilities and minimal absorption in nontumor cells, as confirmed by single-photon emission computed tomography. Notably, the ratios of tumor to muscle and tumor to intestine, 1 h postinjection, were 4.78 ± 0.86 and 3.24 ± 0.47, respectively. Comparable ratios were observed in orthotopic CRC models, recording 4.94 ± 0.32 and 3.88 ± 0.41, respectively. In summary, [99mTc]Tc-HYNIC-cycOn shows substantial promise as a candidate for clinical applications. We show that [99mTc]Tc-HYNIC-cycOn can effectively target and visualize c-Met-expressing tumors in vivo, providing a promising approach for enhancing diagnostic accuracy when detecting c-Met in CRC.

Selective inhibition of c-Met signaling pathways with a bispecific DNA nanoconnector for the targeted therapy of cancer

Hepatocyte growth factor receptor (c-Met) is a suitable molecular target for the targeted therapy of cancer. Novel c-Met-targeting drugs need to be developed because conventional small-molecule inhibitors and antibodies of c-Met have some limitations. To synthesize such drugs, we developed a bispecific DNA nanoconnector (STPA) to inhibit c-Met function. STPA was constructed by using DNA triangular prism as a scaffold and aptamers as binding molecules. After c-Met-specific SL1 and nucleolin-specific AS1411 aptamers were integrated with STPA, STPA could bind to c-Met and nucleolin on the cell membrane. This led to the formation of the c-Met/STPA/nucleolin complex, which in turn blocked c-Met activation. In vitro experiments showed that STPA could not only inhibit the c-Met signaling pathways but also facilitate c-Met degradation through lysosomes. STPA also inhibited c-Met-promoted cell migration, invasion, and proliferation. The results of in vivo experiments showed that STPA could specifically target to tumor site in xenograft mouse model, and inhibit tumor growth with low toxicity by downregulating c-Met pathways. This study provided a novel and simple strategy to develop c-Met-targeting drugs for the targeted therapy of cancer.

Prominent response to savolitinib monotherapy in high-grade fetal adenocarcinoma with MET amplification and concurrent brain metastasis: a case report

Background

Mesenchymal-epithelial transition (MET) represents a potential therapeutic target in various cancers, with amplification of the MET gene identified in a subset of patients with pulmonary adenocarcinomas. However, MET gene amplification is rarely observed in high-grade fetal adenocarcinoma (H-FLAC).

Case Description

Here we present a novel case of a patient diagnosed with stage IV H-FLAC harboring MET amplifications and treated with savolitinib. The 69-year-old male patient, who presented with a primary complaint of cough and white sputum, had a history of hypertension for over 10 years and a 45-year smoking history. The patient received savolitinib monotherapy treatment due to brain metastases. Despite the omission of radiotherapy for asymptomatic brain metastases, a notable response to savolitinib therapy was observed, with a partial response (PR) achieved after 4 weeks and a reduction in the brain tumor. At the time of the submission of this report, the patient received over 24 weeks of savolitinib treatment, and was maintained PR. The patient was still undergoing treatment. This highlights the potential clinical benefits of targeted therapy against MET amplification in H-FLAC.

Conclusions

H-FLAC harboring MET amplification and brain metastasis is rare. Treatment with savolitinib monotherapy resulted in a PR, providing preliminary insights to the efficacy of savolitinib for H-FLAC with MET amplification.

Insights into the Clinical, Biological and Therapeutic Impact of Copy Number Alteration in Cancer

Copy number alterations (CNAs), resulting from the gain or loss of genetic material from as little as 50 base pairs or as big as entire chromosome(s), have been associated with many congenital diseases, de novo syndromes and cancer. It is established that CNAs disturb the dosage of genomic regions including enhancers/promoters, long non-coding RNA and gene(s) among others, ultimately leading to an altered balance of key cellular functions. In cancer, CNAs have been associated with almost all steps of the disease: predisposition, initiation, development, maintenance, response to treatment, resistance, and relapse. Therefore, understanding how specific CNAs contribute to tumourigenesis may provide prognostic insight and ultimately lead to the development of new therapeutic approaches to improve patient outcomes. In this review, we provide a snapshot of what is currently known about CNAs and cancer, incorporating topics regarding their detection, clinical impact, origin, and nature, and discuss the integration of innovative genetic engineering strategies, to highlight the potential for targeting CNAs using novel, dosage-sensitive and less toxic therapies for CNA-driven cancer.

Joint DNA-RNA-based NGS for diagnosis and treatment of a rare CD47-MET fusion lung adenocarcinoma which was immunoresistant and savoltinib-sensitive: a case report

Targeted therapy and immunotherapy are both important in the treatment of non-small-cell lung cancer (NSCLC). Accurate diagnose and precise treatment are key in achieving long survival of patients. MET fusion is a rare oncogenic factor, whose optimal detection and treatment are not well established. Here, we report on a 32-year-old female lung adenocarcinoma patient with positive PD-L1 and negative driver gene detected by DNA-based next-generation sequencing (NGS). A radical resection of the primary lesion after chemotherapy combined with PD-1 checkpoint inhibitor administration indicated primary immuno-resistance according to her pathological response and rapid relapse. A rare CD47-MET was detected by RNA-based NGS, which was confirmed by fluorescence in situ hybridization. Multiplex immunofluorescence revealed a PD-L1 related heterogeneous immunosuppressive microenvironment with little distribution of CD4+ T cells and CD8+ T cells. Savolitinib therapy resulted in a progression-free survival (PFS) of >12 months, until a new secondary resistance mutation in MET p.D1228H was detected by re-biopsy and joint DNA-RNA-based NGS after disease progression. In this case, CD47-MET fusion NSCLC was primarily resistant to immunotherapy, sensitive to savolitinib, and developed secondary MET p.D1228H mutation after targeted treatment. DNA-RNA-based NGS is useful in the detection of such molecular events and tracking of secondary mutations in drug resistance. To this end, DNA-RNA-based NGS may be of better value in guiding precise diagnosis and individualized treatment in this patient population.

Tigilanol Tiglate-Induced Changes in Secretome Profiles Alter C-Met Phosphorylation and Cell Surface Protein Expression in H357 Head and Neck Cancer Cells

Tigilanol tiglate (TT, also known as EBC-46) is a novel, plant-derived diterpene ester possessing anticancer and wound-healing properties. Here, we show that TT-evoked PKC-dependent S985 phosphorylation of the tyrosine kinase MET leads to subsequent degradation of tyrosine phosphorylated p-Y1003 and p-Y1234/5 MET species. PKC inhibition with BIM-1 blocked S985 phosphorylation of MET and led to MET cell surface accumulation. Treatment with metalloproteinase inhibitors prevented MET-ECD release into cell culture media, which was also blocked by PKC inhibitors. Furthermore, unbiased secretome analysis, performed using TMT-technology, identified additional targets of TT-dependent release of cell surface proteins from H357 head and neck cancer cells. We confirm that the MET co-signalling receptor syndecan-1 was cleaved from the cell surface in response to TT treatment. This was accompanied by rapid cleavage of the cellular junction adhesion protein Nectin-1 and the nerve growth factor receptor NGFRp75/TNFR16. These findings, that TT is a novel negative regulator of protumorigenic c-MET and NGFRp75/TNFR16 signalling, as well as regulating Nectin-1-mediated cell adhesion, further contribute to our understanding of the mode of action and efficacy of TT in the treatment of solid tumours.

MET Oncogene Targeting for Cancer Immunotherapy

The MET receptor is one of the main drivers of 'invasive growth', a multifaceted biological response essential during embryonic development and tissue repair that is usurped by cancer cells to induce and sustain the malignant phenotype. MET stands out as one of the most important oncogenes activated in cancer and its inhibition has been explored since the initial era of cancer-targeted therapy. Different approaches have been developed to hamper MET signaling and/or reduce MET (over)expression as a hallmark of transformation. Considering the great interest gained by cancer immunotherapy, this review evaluates the opportunity of targeting MET within therapeutic approaches based on the exploitation of immune functions, either in those cases where MET impairment is crucial to induce an effective response (i.e., when MET is the driver of the malignancy), or when blocking MET represents a way for potentiating the treatment (i.e., when MET is an adjuvant of tumor fitness).

Immune-related signature identifies IL1R2 as an immunological and prognostic biomarker in pancreatic cancer

Objective

Pancreatic cancer is one of the most aggressive malignancies, a robust prognostic signature and novel biomarkers are urgently needed for accurate stratification of the patients and optimization of clinical decision-making.

Methods

A list of bioinformatic analysis were applied in public dataset to construct an immune-related signature. Furthermore, the most pivotal gene in the signature was identified. The potential mechanism of the core gene function was revealed through GSEA, CIBERSORT, ESTIMATE, immunophenoscore (IPS) algorithm, single-cell analysis, and functional experiment.

Results

An immune-related prognostic signature and associated nomogram were constructed and validated. Among the genes constituting the signature, interleukin 1 receptor type II (IL1R2) was identified as the gene occupying the most paramount position in the risk signature. Meanwhile, knockdown of IL1R2 significantly inhibited the proliferation, invasion, and migration ability of pancreatic cancer cells. Additionally, high IL1R2 expression was associated with reduced CD8+ T cell infiltration in pancreatic cancer microenvironment, which may be due to high programmed cell death-ligand-1 (PD-L1) expression in cancer cells. Finally, the IPS algorithm proved that patients with high IL1R2 expression possessed a higher tumor mutation burden and a higher probability of benefiting from immunotherapy.

Conclusion

In conclusion, our study constructed an efficient immune-related prognostic signature and identified the key role of IL1R2 in the development of pancreatic cancer, as well as its potential to serve as a biomarker for immunotherapy efficacy prediction for pancreatic cancer.

Bispecific Nanobody-Aptamer Conjugates for Enhanced Cancer Therapy in Solid Tumors

Bispecific antibodies possess exceptional potential as therapeutic agents due to their capacity to bind to two different antigens simultaneously. However, challenges pertain to unsatisfactory stability, manufacturing complexity, and limited tumor penetration hinder their broad applicability. In this study, a versatile technology is presented for the rapid generation of bispecific nanobody-aptamer conjugates with efficient tumor penetration. The approach utilizes microbial transglutaminase (MTGase) and click chemistry to achieve site-specific conjugation of nanobodies and aptamers, which are termed nanotamers. The nanotamers recognize and bind to two types of molecular targets expressed on cancer cells. As a prototype, a bispecific nanotamer is developed that binds both clusters of differentiation 47 (CD47) and mesenchymal epithelial transition receptor (Met) expressed on the tumor cell membrane. This CD47-Met nanotamer demonstrates high affinity and specificity toward tumor cells expressing both targets, exhibits improved receptor functional inhibition through a strong steric hindrance effect. Moreover, its capacity for deep tumor penetration greatly enhances the impact of conventional chemotherapy on antitumor efficacy. The as-developed nanotamer synthesis approach shows promise to customize bispecific molecular probes targeting different cancer types and different therapeutic goals.

A novel HLA-DQB2::MET gene fusion variant in lung adenocarcinoma with prolonged response to tepotinib: a case report

Background

MET rearrangements are infrequently observed in non-small cell lung cancer (NSCLC). Advanced genomic detection techniques have unveiled such infrequent genomic variations, particularly MET fusions in approximately 0.5% of NSCLC patients. Tyrosine kinase inhibitors (TKIs) have revolutionized the standard of care in lung cancer and more recently a second generation MET TKI tepotinib received Food and Drug Administration (FDA) approval for MET exon 14 alterations in metastatic NSCLC. Despite this, the therapeutic landscape for MET-rearranged NSCLC patients remains significantly unexplored. The aim of our report is to detail a unique case of a patient with metastatic lung adenocarcinoma with a novel HLA-DQB2::MET fusion detected by next-generation sequencing (NGS) following previous treatment resistance.

Case Description

A 73-year-old female was initially started on carboplatin, pemetrexed and pembrolizumab with maintenance, but eventually had progression in the left upper lobe (LUL). Upon progression she was enrolled in a clinical trial of a monoclonal antibody with or without a PD-1 inhibitor, but brain metastasis progression was eventually detected by magnetic resonance imaging (MRI) requiring stereotactic radiosurgery (SRS) and a craniotomy. The trial drug was eventually discontinued due to progression and toxicity and NGS on bronchoscopy tissue revealed HLA-DQB2::MET fusion. The patient was initiated on tepotinib and continues with clinical and radiological stable disease for over 12 months. The patient's response to a MET inhibitor, tepotinib, underscores the potential efficacy of selective MET inhibitors for individuals with previously unexplored MET fusions.

Conclusions

The positive response to tepotinib of a patient with NSCLC harboring a novel MET-Fusion underscores the importance of the use of comprehensive next-generational sequencing-based panels and highlights the necessity for additional research and clinical exploration of selective MET inhibitors for managing NSCLC with MET rearrangements.

Comparison of Breast Fine-Needle Aspiration Cytology and Tissue Sampling for High-Throughput Proteomic Analysis and Cancer Biomarker Detection

INTRODUCTION

Fine-needle aspiration cytology (FNAC) specimens are widely utilized for the diagnosis and molecular testing of various cancers. We performed a comparative proteomic analysis of three different sample types, including breast FNAC, core needle biopsy (CNB), and surgical resection tissues. Our goal was to evaluate the suitability of FNAC for in-depth proteomic analysis and for identifying potential therapeutic biomarkers in breast cancer.

METHODS

High-throughput proteomic analysis was conducted on matched FNAC, CNB, and surgical resection tissue samples obtained from breast cancer patients. The protein identification, including currently established or promising therapeutic targets, was compared among the three different sample types. Gene Ontology (GO) enrichment analysis was also performed on all matched samples.

RESULTS

Compared to tissue samples, FNAC testing revealed a comparable number of proteins (7,179 in FNAC; 7,196 in CNB; and 7,190 in resection samples). Around 85% of proteins were mutually identified in all sample types. FNAC, along with CNB, showed a positive correlation between the number of enrolled tumor cells and identified proteins. In the GO analysis, the FNAC samples demonstrated a higher number of genes for each pathway and GO terms than tissue samples. CCND1, CDK6, HER2, and IGF1R were found in higher quantities in the FNAC compared to tissue samples, while TUBB2A was only detected in the former.

CONCLUSION

FNAC is suitable for high-throughput proteomic analysis, in addition to an emerging source that could be used to identify and quantify novel cancer biomarkers.

Mesenchymal-epithelial transition factor amplification correlates with adverse pathological features and poor clinical outcome in colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is the third most common cancer and the second most common cause of cancer-related mortality worldwide. Mesenchymal-epithelial transition factor (MET) gene participates in multiple tumor biology and shows clinical potential for pharmacological manipulation in tumor treatment. MET amplification has been reported in CRC, but data are very limited. Investigating pathological values of MET in CRC may provide new therapeutic and genetic screening options in future clinical practice.

AIM

To determine the pathological significance of MET amplification in CRC and to propose a feasible screening strategy.

METHODS

A number of 205 newly diagnosed CRC patients undergoing surgical resection without any preoperative therapy at Shenzhen Cancer Hospital of Chinese Academy of Medical Sciences were recruited. All patients were without RAS/RAF mutation or microsatellite instability-high. MET amplification and c-MET protein expression were analyzed using fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC), respectively. Correlations between MET aberration and pathological features were detected using the chi-squared test. Progression free survival (PFS) during the two-year follow-up was detected using the Kaplan-Meier method and log rank test. The results of MET FISH and IHC were compared using one-way ANOVA.

RESULTS

Polysomy-induced MET amplification was observed in 14.4% of cases, and focal MET amplification was not detected. Polysomy-induced MET amplification was associated with a higher frequency of lymph node metastasis (LNM) (P < 0.001) and higher tumor budding grade (P = 0.02). In the survival analysis, significant difference was detected between patients with amplified- and non-amplified MET in a two-year follow-up after the first diagnosis (P = 0.001). C-MET scores of 0, 1+, 2+, and 3+ were observed in 1.4%, 24.9%, 54.7%, and 19.0% of tumors, respectively. C-MET overexpression correlated with higher frequency of LNM (P = 0.002), but no significant difference of PFS was detected between patients with different protein levels. In terms of concordance between MET FISH and IHC results, MET copy number showed no difference in c-MET IHC 0/1+ (3.35 ± 0.18), 2+ (3.29 ± 0.11) and 3+ (3.58 ± 0.22) cohorts, and the MET-to-CEP7 ratio showed no difference in three groups (1.09 ± 0.02, 1.10 ± 0.01, and 1.09 ± 0.03).

CONCLUSION

In CRC, focal MET amplification was a rare event. Polysomy-induced MET amplification correlated with adverse pathological characteristics and poor prognosis. IHC was a poor screening tool for MET amplification.

Role of savolitinib in advanced gastric adenocarcinoma with meningeal carcinomatosis and cerebellar metastasis: A case report

BACKGROUND

Brain metastases (BM) are very rare in gastric adenocarcinoma (GaC), and patients with BMs have a higher mortality rate due to stronger tumor aggressiveness. However, its pathogenesis remains unclear. Genetic testing revealed cellular-mesenchymal epithelial transition factor receptor (MET) amplification. Therefore, treatment with savolitinib, a small molecule inhibitor of c-Met, was selected.

CASE SUMMARY

A 66-year-old woman was diagnosed with advanced GaC 6 months prior to presentation due to back pain. Cerebellar and meningeal metastases were observed during candonilimab combined with oxaliplatin and capecitabine therapy. The patient experienced frequent generalized seizures and persistent drowsiness in the emergency department. Genetic testing of cerebrospinal fluid and peripheral blood revealed increased MET amplification. After discussing treatment options with the patient, savolitinib tablets were administered. After a month of treatment, the intracranial lesions shrank considerably.

CONCLUSION

BM is very rare in advanced GaC, especially in meningeal cancer, that is characterized by rapid disease deterioration. There are very few effective treatment options available; however, technological breakthroughs in genomics have provided a basis for personalized treatment. Furthermore, MET amplification may be a key driver of BM in gastric cancer; however, this conclusion requires further investigation.

Cancer Cell-Selective PD-L1 Inhibition via a DNA Safety Catch to Enhance Immunotherapy Specificity

Immune checkpoint protein blockade (ICB) has emerged as a powerful immunotherapy approach, but suppressing immune-related adverse events (irAEs) for noncancerous cells and normal tissues remains challenging. Activatable ICB has been developed with tumor microenvironment highly-expressed molecules as stimuli, but they still lack precision and efficiency considering the diffusion of stimuli molecules in whole tumor tissue. Here we assemble PD-L1 with a duplex DNA strand, termed as "safety catch", to regulate its accessibility for ICB. The safety catch remains at "on" status for noncancerous cells to prevent ICB binding to PD-L1. Cancer cell membrane protein c-Met acts as a trigger protein to react with safety catch, which selectively exposes its hybridization region for ICB reagent. The ICB reagent is a retractable DNA nanostring with repeating hairpin-structural units, whose contraction drives PD-L1 clustering with endocytosis-guided degradation. The safety catch, even remained at "safety on" status, is removed from the cell membrane via a DNA strand displacement reaction to minimize its influence on noncancerous cells. This strategy demonstrates selective and potent immunotherapeutic capabilities only against cancer cells both in vitro and in vivo, and shows effective suppression of irAEs in normal tissues, therefore would become a promising approach for precise immunotherapy in mice.

Bispecific antibody drug conjugates: Making 1+1>2

Bispecific antibody‒drug conjugates (BsADCs) represent an innovative therapeutic category amalgamating the merits of antibody‒drug conjugates (ADCs) and bispecific antibodies (BsAbs). Positioned as the next-generation ADC approach, BsADCs hold promise for ameliorating extant clinical challenges associated with ADCs, particularly pertaining to issues such as poor internalization, off-target toxicity, and drug resistance. Presently, ten BsADCs are undergoing clinical trials, and initial findings underscore the imperative for ongoing refinement. This review initially delves into specific design considerations for BsADCs, encompassing target selection, antibody formats, and the linker-payload complex. Subsequent sections delineate the extant progress and challenges encountered by BsADCs, illustrated through pertinent case studies. The amalgamation of BsAbs with ADCs offers a prospective solution to prevailing clinical limitations of ADCs. Nevertheless, the symbiotic interplay among BsAb, linker, and payload necessitates further optimizations and coordination beyond a simplistic "1 + 1" to effectively surmount the extant challenges facing the BsADC domain.

TWIST1 is a critical downstream target of the HGF/MET pathway and is required for MET driven acquired resistance in oncogene driven lung cancer

MET amplification/mutations are important targetable oncogenic drivers in NSCLC, however, acquired resistance is inevitable and the majority of patients with targetable MET alterations fail to respond to MET tyrosine kinase inhibitors (TKIs). Furthermore, MET amplification is among the most common mediators of TKI resistance. As such, novel therapies to target MET pathway and overcome MET TKI resistance are clearly needed. Here we show that the epithelial-mesenchymal transition (EMT) transcription factor, TWIST1 is a key downstream mediator of HGF/MET induced resistance through suppression of p27 and targeting TWIST1 can overcome resistance. We found that TWIST1 is overexpressed at the time of TKI resistance in multiple MET-dependent TKI acquired resistance PDX models. We have shown for the first time that MET directly stabilized the TWIST protein leading to TKI resistance and that TWIST1 was required for MET-driven lung tumorigenesis as well as could induce MET TKI resistance when overexpressed. TWIST1 mediated MET TKI resistance through suppression of p27 expression and genetic or pharmacologic inhibition of TWIST1 overcame TKI resistance in vitro and in vivo. Our findings suggest that targeting TWIST1 may be an effective therapeutic strategy to overcome resistance in MET-driven NSCLC as well as in other oncogene driven subtypes in which MET amplification is the resistance mechanism.

Unlocking c-MET: A comprehensive journey into targeted therapies for breast cancer

Breast cancer is the most common malignancy among women, posing a formidable health challenge worldwide. In this complex landscape, the c-MET (cellular-mesenchymal epithelial transition factor) receptor tyrosine kinase (RTK), also recognized as the hepatocyte growth factor (HGF) receptor (HGFR), emerges as a prominent protagonist, displaying overexpression in nearly 50% of breast cancer cases. Activation of c-MET by its ligand, HGF, secreted by neighboring mesenchymal cells, contributes to a cascade of tumorigenic processes, including cell proliferation, metastasis, angiogenesis, and immunosuppression. While c-MET inhibitors such as crizotinib, capmatinib, tepotinib and cabozantinib have garnered FDA approval for non-small cell lung cancer (NSCLC), their potential within breast cancer therapy is still undetermined. This comprehensive review embarks on a journey through structural biology, multifaceted functions, and intricate signaling pathways orchestrated by c-MET across cancer types. Furthermore, we highlight the pivotal role of c-MET-targeted therapies in breast cancer, offering a clinical perspective on this promising avenue of intervention. In this pursuit, we strive to unravel the potential of c-MET as a beacon of hope in the fight against breast cancer, unveiling new horizons for therapeutic innovation.

MET is a new confirmed gene responsible for familial distal arthrogryposis

In this Correspondence, F. Mari and colleagues report a second two-generation family with distal arthrogryposis caused by a mutation in MET tyrosine kinase.

Comparison of an amplicon-based large panel next generation sequencing (NGS) assay with conventional testing methods for MET and HER2 amplification in lung and breast cancers

The frequency of MET and HER2 amplification being detected by next generation sequencing (NGS) is increasing due to NGS being increasingly adopted for molecular profiling of cancers. However, the accuracy of NGS in detecting these gene amplifications remains uncertain due to conflicting reports in the scientific literature. We studied the accuracy of an amplicon-based large panel NGS assay in detecting MET and HER2 amplification in lung and breast cancers, respectively, by comparing it against conventional testing methods. Amongst 48 lung cancers, four of five cancers that were MET amplified on fluorescence in situ hybridisation (FISH) were classified as amplified on NGS while 42 of the remaining 43 non-amplified cancers were classified as non-amplified on NGS, giving a sensitivity of 80%, specificity of 97.7% and overall concordance of 95.8%. Of the 46 breast cancers tested, only six of the nine cancers that were HER2-positive on immunohistochemistry (IHC)/FISH were HER2-positive on NGS, while all the remaining HER2-negative cases were negative on NGS, giving a sensitivity of 66.7%, specificity of 100% and overall concordance of 93.5%. All the false-negative cases had low level gene amplification (MET:CEP7 or HER2:CEP17 FISH ratio of <3). The low sensitivity for HER2 amplification may be confounded by the small sample size and disproportionate number of cases with low level amplification. In summary, the NGS assay has good concordance with conventional testing methods but may be less sensitive in detecting low level gene amplification.

Unraveling the Significance of MET Focal Amplification in Lung Cancer: Integrative NGS, FISH, and IHC Investigation

MET amplification (METamp) represents a promising therapeutic target in non-small cell lung cancer, but no consensus has been established to identify METamp-dependent tumors that could potentially benefit from MET inhibitors. In this study, an analysis of MET amplification/overexpression status was performed in a retrospectively recruited cohort comprising 231 patients with non-small cell lung cancer from Shanghai Chest Hospital (SCH cohort) using 3 methods: fluorescence in situ hybridization (FISH), hybrid capture-based next-generation sequencing, and immunohistochemistry for c-MET and phospho-MET. The SCH cohort included 130 cases known to be METamp positive by FISH and 101 negative controls. The clinical relevance of these approaches in predicting the efficacy of MET inhibitors was evaluated. Additionally, next-generation sequencing data from another 2 cohorts including 22,010 lung cancer cases were utilized to examine the biological characteristics of different METamp subtypes. Of the 231 cases, 145 showed MET amplification/overexpression using at least 1 method, whereas only half of them could be identified by all 3 methods. METamp can occur as focal amplification or polysomy. Our study revealed that the inconsistency between next-generation sequencing and FISH primarily occurred in the polysomy subtype. Further investigations indicated that compared with polysomy, focal amplification correlated with fewer co-occurring driver mutations, higher protein expressions of c-MET and phospho-MET, and higher incidence in acquired resistance than in de novo setting. Moreover, patients with focal amplification presented a more robust response to MET inhibitors compared with those with polysomy. Notably, a strong correlation was observed between focal amplification and programmed cell death ligand-1 expression, indicating potential therapeutic implications with combined MET inhibitor and immunotherapy for patients with both alterations. Our findings provide insights into the molecular complexity and clinical relevance of METamp in lung cancer, highlighting the role of MET focal amplification as an oncogenic driver and its feasibility as a primary biomarker to further investigate the clinical activity of MET inhibitors in future studies.