c-Met Expression Research Articles

Targeting c-MET for Endoscopic Detection of Dysplastic Lesions Within Barrett's Esophagus Using EMI-137 Fluorescence Imaging.

Esophageal cancer (EC) carries a poor prognosis with 5-year overall survival of less than 20%. Barrett's esophagus (BE) increases the risk of esophageal adenocarcinoma (EAC). The aim of this study was to investigate the ability of EMI-137, a mesenchymal-epithelial transition factor (c-MET)-targeting optical imaging tracer, to detect dysplasia in BE. c-MET expression in human esophageal tissue was investigated using Gene Expression Omnibus (GEO) datasets, tissue microarrays and BE biopsies. EMI-137 was tested in a dual xenograft mouse model bearing OE33 (c-MET high expression) and FLO-1 (c-MET low expression) tumors. Fluorescence molecular endoscopy (FME) was performed in a mouse model of Barrett's-like metaplasia and dysplasia (L2-IL1β). Tumors and organs-of-interest were evaluated through ex vivo fluorescence imaging. MET mRNA expression analyses and c-MET immunostaining confirmed upregulation of c-MET in BE and EAC compared to normal epithelium. There was strong accumulation of EMI-137 in OE33 xenografts 3 h post injection decreasing by more than 50% on co-injection of a 10-fold molar excess of unlabeled EMI-137. The target-to background ratio (TBR) at 3 h p.i. for OE33 and FLO-1 tumors was 10.08 and 1.42, respectively. FME of L2-IL1β mice showed uptake of EMI-137 in dysplastic lesions within BE with a TBR of 1.9 in vivo, and greater than 2 in ex vivo fluorescence imaging. EMI-137 accumulates in dysplastic lesions within BE and in c-MET positive EAC. EMI-137 imaging has potential as a screening and surveillance tool for patients with BE and as a means to detecting dysplasia and EAC.

Xanthohumol overcomes osimertinib resistance via governing ubiquitination-modulated Ets-1 turnover

Non-small cell lung cancer (NSCLC) is a prevalent and fatal malignancy with a significant global impact. Recent advancements have introduced targeted therapies like tyrosine kinase inhibitors (TKIs) such as osimertinib, which have improved patient outcomes, particularly in those with EGFR mutations. Despite these advancements, acquired resistance to TKIs remains a significant challenge. Hence, one of the current research priorities is understanding the resistance mechanisms and identifying new therapeutic targets to improve therapeutic efficacy. Herein, we identified high expression of c-Met in osimertinib-resistant NSCLC cells, and depletion of c-Met significantly inhibited the proliferation of osimertinib-resistant cells and prolonged survival in mice, suggesting c-Met as an attractive therapeutic target. To identify effective anti-tumor agents targeting c-Met, we screened a compound library containing 641 natural products and found that only xanthohumol exhibited potent inhibitory effects against osimertinib-resistant NSCLC cells. Moreover, combination treatment with xanthohumol and osimertinib sensitized osimertinib-resistant NSCLC cells to osimertinib both in vitro and in vivo. Mechanistically, xanthohumol disrupted the interaction between USP9X and Ets-1, and inhibited the phosphorylation of Ets-1 at Thr38, promoting its degradation, thereby targeting the Ets-1/c-Met signaling axis and inducing intrinsic apoptosis in osimertinib-resistant NSCLC cells. Overall, the research highlights the critical role of targeting c-Met to address osimertinib resistance in NSCLC. By demonstrating the efficacy of xanthohumol in overcoming resistance and enhancing therapeutic outcomes, this study provides valuable insights and potential new strategies for improving the clinical management of NSCLC.

Enhanced tumoricidal activity of PD-1 antibody-secreting c-Met CAR-T cells against pancreatic cancer cells

To construct c-Met CAR-T cells secreting PD-1 antibodies to reduce immune inhibitory effect of tumor cells and enhance the efficacy of CAR-T cell therapy against pancreatic cancer. Kaplan-Meier Plotter, GEPIA, and Timer 2.0 bioinformatics databases were used to analyze c-Met expression in pancreatic cancer and its correlation with survival and immune infiltration status. In clinical samples of pancreatic cancer and pancreatic cancer Aspc-1 cells, c-Met and PD-L1 expressions were detected using immunohistochemistry or flow cytometry. Using gene editing technology, PD-1 secretory antibodies and HIS tags were linked to second-generation c-Met CAR molecules to construct PD-1/c-Met CAR plasmids, which were then packaged into lentiviruses for infection of activated T cells. The positive rate and cell subset distribution of CAR-T cells were analyzed with flow cytometry, and secretory PD-1 antibodies in cell supernatants were detected using Western blotting. The target cell killing efficiency and proliferative activity of the modified CAR-T cells were evaluated after activation, and cytokine secretion was analyzed using ELISA. The expression of c-Met was significantly higher in pancreatic cancer than in normal tissues, and its expression level was negatively correlated with the patients' survival and positively correlated with immune cell infiltration. The clinical samples of pancreatic cancer tissues expressed significantly higher levels of c-Met and PD-L1 than the adjacent tissues, and 90.7% and 57.7% of Aspc-1 cells were positive for c-Met and PD-L1, respectively. The constructed PD-1/c-Met CAR-T cells were capable of secreting PD-1 antibodies and showed a significantly higher killing efficiency against tumor cells than c-Met CAR-T cells at an effector-to-target ratio of 20: 1, with also a higher proliferative activity after target cell stimulation and higher levels of IL-2 and TNF-α secretin. PD-1/c-Met CAR-T cells have higher killing efficiency against pancreatic cancer cells with also higher proliferative activity than c-Met CAR-T cells.

EP.08B.02 The Impact of C-Met Expression on the Immune Microenvironment and Survival in Locally Advanced Non-Small Cell Lung Cancer

EP.08B.02 The Impact of C-Met Expression on the Immune Microenvironment and Survival in Locally Advanced Non-Small Cell Lung Cancer

Histopathologic classification and immunohistochemical features of papillary renal neoplasm with potential therapeutic targets.

Papillary renal cell carcinoma (pRCC) is the second most common histological subtype of renal cell carcinoma and is considered a morphologically and molecularly heterogeneous tumor. Accurate classification and assessment of the immunohistochemical features of possible therapeutic targets are needed for precise patient care. We aimed to evaluate immunohistochemical features and possible therapeutic targets of papillary renal neoplasms. We collected 140 papillary renal neoplasms from three different hospitals and conducted immunohistochemical studies on tissue microarray slides. We performed succinate dehydrogenase B, fumarate hydratase, and transcription factor E3 immunohistochemical studies for differential diagnosis and re-classified five cases (3.6%) of papillary renal neoplasms. In addition, we conducted c-MET, p16, c-Myc, Ki-67, p53, and stimulator of interferon genes (STING) immunohistochemical studies to evaluate their pathogenesis and value for therapeutic targets. We found that c-MET expression was more common in pRCC (classic) (p = .021) among papillary renal neoplasms and Ki-67 proliferation index was higher in pRCC (not otherwise specified, NOS) compared to that of pRCC (classic) and papillary neoplasm with reverse polarity (marginal significance, p = .080). Small subsets of cases with p16 block positivity (4.5%) (pRCC [NOS] only) and c-Myc expression (7.1%) (pRCC [classic] only) were found. Also, there were some cases showing STING expression and those cases were associated with increased Ki-67 proliferation index (marginal significance, p = .063). Our findings suggested that there are subsets of pRCC with c-MET, p16, c-MYC, and STING expression and those cases could be potential candidates for targeted therapy.

Prognostic Significance of EGFR, HER2, and c-Met Overexpression in Surgically Treated Patients with Adenocarcinoma of the Ampulla of Vater.

Adenocarcinoma of the ampulla of Vater (AAC) is a rare malignancy with heterogeneous tumors arising from various histologic subtypes, necessitating new therapeutic strategies. This study examines epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), and c-Met expression in AAC, given their potential as druggable targets. Among 87 patients who underwent curative resection, EGFR overexpression was found in 87.4%, HER2 in 11.5%, and c-Met in 50%. EGFR overexpression was more common in the pancreatobiliary subtype (p = 0.018) and associated with a higher histologic grade (p = 0.008). HER2 did not correlate with clinicopathological features, while c-Met was more common in node-negative groups (p = 0.004) and often co-expressed with EGFR (p = 0.049). EGFR-positive patients had worse disease-free (HR = 2.89; 95% CI, 1.35-6.20; p = 0.061) and overall survival (HR = 6.89; 95% CI, 2.94-16.2; p = 0.026) than EGFR-negative patients. HER2-positive AAC showed a trend towards shorter survival, although not statistically significant, and c-Met had no impact on survival outcomes. In the context of systemic disease, survival outcomes did not vary according to EGFR, HER2, and c-Met expression, but the HER2-positive group showed a trend towards inferior progression-free survival (HR = 1.90; 95% CI, 0.56-6.41; p = 0.166). This study underscores the potential of EGFR, HER2, and c-Met as targets for personalized therapy in AAC, warranting further research to evaluate targeted treatments.

Design, Synthesis and Evaluation of a Novel Teoptinib Derivative as an Effective Anti-hepatocellular Carcinoma Agent.

Hepatocellular Carcinoma (HCC) is a type of liver cancer known for its poor prognosis and high mortality. Teoptinib is a highly selective MET inhibitor that has been used in the treatment of liver cancer. Although good progress has been made in clinical treatment, further improvement is still needed. In this study, a series of novel Teoptinib derivatives were synthesized and evaluated as anti-cancer agents for the treatment of liver cancer, and an oral nanodrug delivery system was also explored. A series of novel Teoptinib derivatives were synthesized, and an oral nanodrug delivery system was also explored. HPLC, high-resolution mass spectrometer and NMR were used to determine the structure and molecular formula of the synthesized compounds. Zeta potential assay was used to access the particle size distribution and zeta potential of the nanoparticles. MTT assay, cell colony formation assay, cell apoptosis inhibition assay, cell scratch assay, and the MHCC-97H xenograft model of nude mice assay were used to evaluate the in vitro and in vivo anti-tumor activity of the synthesized compounds. Compound (R)-10 showed the best antitumor activity with 0.010 μM of the IC50 value against MHCC-97H, a human liver cancer cell line with high c-Met expression. The MHCC-97H xenograft model of nude mice assay showed that nano-prodrug of compound (R)-10 exhibited good in vivo activity with 87.67% of the TGI at the dosage of 8 mg/kg. We designed and synthesized a series of c-Met inhibitors containing different side chains and chiral centers as anti-liver cancer agents. Among them, compound (R)-10 shows a promising effect as a lead molecule for further study in the treatment of liver cancer. The successful incorporation of (R)-10 into a novel oral nanodrug delivery system highlights the importance of effective drug delivery systems for enhanced therapeutic efficacy.

Reproducibility of c-Met Immunohistochemical Scoring (Clone SP44) for Non-Small Cell Lung Cancer Using Conventional Light Microscopy and Whole Slide Imaging.

Emerging therapies for non-small cell lung cancer targeting c-Met overexpression have recently demonstrated promising results. However, the evaluation of c-Met expression can be challenging. We aimed to study the inter and intraobserver reproducibility of c-Met expression evaluation. One hundred ten cases with non-small cell lung cancer (40 biopsies and 70 surgical specimens) were retrospectively selected in a single laboratory (LPCE) and evaluated for c-Met expression. Six pathologists (4 seniors and 2 juniors) evaluated the H-score and made a 3-tier classification of c-Met expression for all cases, using conventional light microscopy (CLM) and whole slide imaging (WSI). The interobserver reproducibility with CLM gave global Cohen Kappa coefficients (ƙ) ranging from 0.581 (95% CI: 0.364-0.771) to 0.763 (95% CI: 0.58-0.92) using the c-Met 3-tier classification and H-score, respectively. ƙ was higher for senior pathologists and biopsy samples. The interobserver reproducibility with WSI gave a global ƙ ranging from 0.543 (95% CI: 0.33-0.724) to 0.905 (95% CI: 0.618-1) using the c-Met H-score and 2-tier classification (≥25% 3+), respectively. ƙ for intraobserver reproducibility between CLM and WSI ranged from 0.713 to 0.898 for the c-Met H-score and from 0.600 to 0.779 for the c-Met 3-tier classification. We demonstrated a moderate to excellent interobserver agreement for c-Met expression with a substantial to excellent intraobserver agreement between CLM and WSI, thereby supporting the development of digital pathology. However, some factors (scoring method, type of tissue samples, and expertise level) affect reproducibility. Our findings highlight the importance of establishing a consensus definition and providing further training, particularly for inexperienced pathologists, for c-Met immunohistochemistry assessment in clinical practice.

Mesenchymal Stem Cell-Derived Exosomes Mitigate Acute Murine Liver Injury via Ets-1 and Heme Oxygenase-1 Up-regulation.

Mesenchymal stem cells (MSCs)-derived exosomes have been previously demonstrated to promote tissue regeneration in various animal disease models. This study investigated the protective effect of exosome treatment in carbon tetrachloride (CCl4)-induced acute liver injury and delineated possible underlying mechanism. Exosomes collected from conditioned media of previously characterized human umbilical cord-derived MSCs were intravenously administered into male CD-1 mice with CCl4-induced acute liver injury. Biochemical, histological and molecular parameters were used to evaluate the severity of liver injury. A rat hepatocyte cell line, Clone-9, was used to validate the molecular changes by exosome treatment. Exosome treatment significantly suppressed plasma levels of AST, ALT, and pro-inflammatory cytokines, including IL-6 and TNF-α, in the mice with CCl4-induced acute liver injury. Histological morphometry revealed a significant reduction in the necropoptic area in the injured livers following exosome therapy. Consistently, western blot analysis indicated marked elevations in hepatic expression of PCNA, c-Met, Ets-1, and HO-1 proteins after exosome treatment. Besides, the phosphorylation level of signaling mediator JNK was significantly increased, and that of p38 was restored by exosome therapy. Immunohistochemistry double staining confirmed nuclear Ets-1 expression and cytoplasmic localization of c-Met and HO-1 proteins. In vitro studies demonstrated that exosome treatment increased the proliferation of Clone-9 hepatocytes and protected them from CCl4-induced cytotoxicity. Kinase inhibition experiment indicated that the exosome-driven hepatoprotection might be mediated through the JNK pathway. Exosome therapy activates the JNK signaling activation pathway as well as up-regulates Ets-1 and HO-1 expression, thereby protecting hepatocytes against hepatotoxin-induced cell death.

Deregulated immune cell recruitment orchestrated by c-MET impairs pulmonary inflammation and fibrosis

BackgroundPulmonary fibrosis (PF) represents the pathologic end stage of several interstitial lung diseases (ILDs) associated with high morbidity and mortality rates. However, current treatments can only delay disease progression rather than provide a cure. The role of inflammation in PF progression is well-established, but new insights into immune regulation are fundamental for developing more efficient therapies. c-MET signaling has been implicated in the migratory capacity and effector functions of immune cells. Nevertheless, the role of this signaling pathway in the context of PF-associated lung diseases remains unexplored.MethodsTo determine the influence of c-MET in immune cells in the progression of pulmonary fibrosis, we used a conditional deletion of c-Met in immune cells. To induce pulmonary fibrosis mice were administered with bleomycin (BLM) intratracheally. Over the course of 21 days, mice were assessed for weight change, and after euthanasia at different timepoints, bronchoalveolar lavage fluid cells and lung tissue were assessed for inflammation and fibrosis. Furthermore, c-MET expression was assessed in cryobiopsy sections, bronchoalveolar lavage fluid cells samples and single cell RNA-sequencing dataset from human patients with distinct interstitial lung diseases.Resultsc-MET expression was induced in lung immune cells, specifically in T cells, interstitial macrophages, and neutrophils, during the inflammatory phase of BLM-induced PF mouse model. Deletion of c-Met in immune cells correlated with earlier weight recovery and improved survival of BLM-treated mice. Moreover, the deletion of c-Met in immune cells was associated with early recruitment of the immune cell populations, normally found to express c-MET, leading to a subsequent attenuation of the cytotoxic and proinflammatory environment. Consequently, the less extensive inflammatory response, possibly coupled with tissue repair, culminated in less exacerbated fibrotic lesions. Furthermore, c-MET expression was up-regulated in lung T cells from patients with fibrosing ILD, suggesting a potential involvement of c-MET in the development of fibrosing disease.ConclusionsThese results highlight the critical contribution of c-MET signaling in immune cells to their enhanced uncontrolled recruitment and activation toward a proinflammatory and profibrotic phenotype, leading to the exacerbation of lung injury and consequent development of fibrosis.

MYTX-011: a pH-dependent anti-cMET antibody-drug conjugate designed for enhanced payload delivery to cMET expressing tumor cells.

Advances in linker payload technology and target selection have been at the forefront of recent improvements in antibody-drug conjugate (ADC) design, leading to several approvals over the last decade. In contrast, the potential of novel ADC technologies to enhance payload delivery to tumors is relatively underexplored. We demonstrate that incorporation of pH-dependent binding in the antibody component of a cMET targeting ADC (MYTX-011) can overcome the requirement for high cMET expression on tumors, an innovation that has the potential to benefit a broader population of patients with lower cMET levels. MYTX-011 drove four-fold higher net internalization than a non-pH engineered parent ADC in non-small cell lung cancer (NSCLC) cells and showed increased cytotoxicity against a panel of cell lines from various solid tumors. A single dose of MYTX-011 showed at least three-fold higher efficacy than a benchmark ADC in mouse xenograft models of NSCLC ranging from low to high cMET expression. Moreover, MYTX-011 showed improved pharmacokinetics over parent and benchmark ADCs. In a repeat dose toxicology study, MYTX-011 exhibited a toxicity profile similar to other MMAE-based ADCs. These results highlight the potential of MYTX-011 for treating a broader range of NSCLC patients with cMET expression than other cMET targeting ADCs. A first in human study is ongoing to determine the safety, tolerability, and preliminary efficacy of MYTX-011 in patients with NSCLC (NCT05652868).

The immunohistochemical expression of c-MET and RON in lung adenocarcinoma with clinicopathologic correlation

The immunohistochemical expression of c-MET and RON in lung adenocarcinoma with clinicopathologic correlation

First-in-human study of ABBV-400, a novel c-Met–targeting antibody-drug conjugate, in advanced solid tumors: Results in colorectal cancer.

3515 Background: c-Met (MET protein) is frequently overexpressed in several advanced solid tumors including colorectal cancer (CRC). There are no approved therapies specific for c-Met–overexpressing tumors in CRC. The antibody-drug conjugate ABBV-400 comprises c-Met–targeting antibody telisotuzumab conjugated to a novel topoisomerase 1 inhibitor payload. A phase 1 study of ABBV-400 was initiated for adults with advanced solid tumors and progression on standard therapies (NCT05029882); results from dose escalation (ESC) at doses 1.6–6.0 mg/kg once every 3 weeks (Q3W) were previously presented and showed preliminary efficacy (Sharma et al. ASCO 2023. Abstract 3015). We present data from dose ESC and expansion (EXP) cohorts in CRC. Methods: During EXP, patients (pts) with CRC were randomized to receive ABBV-400 at 1.6, 2.4, or 3.0 mg/kg Q3W. Primary objectives were to evaluate the safety, tolerability, pharmacokinetics, preliminary efficacy, and the recommended phase 2 dose of ABBV-400. Results: As of Oct 2023, 122 pts (ESC: 29; EXP: 93) were included. Median age: 56 years; 65 (53%) males. Median prior treatments was 4. Follow-up was longer in ESC vs EXP (14.8 vs 3.8 months). Seventy-eight (64%) pts had a grade (G)≥3 treatment-emergent adverse event (TEAE); 41% had a serious TEAE. Most frequent hematologic TEAEs were anemia (52%; G≥3: 30%), neutropenia (37%; G≥3: 25%), leukopenia (25%; G≥3: 12%), and thrombocytopenia (23%; G≥3: 12%); nonhematologic TEAEs were nausea (57%, G≥3: 3%), fatigue (43%; G≥3: 2%), and vomiting (39%, G≥3: 4%). G≥3 diarrhea was < 1%. Unadjudicated interstitial lung disease/pneumonitis rate was 7% (G≥3: 2%). Treatment-related AEs leading to discontinuation occurred in 11 (9%) pts. Preliminary efficacy outcomes are shown in the Table. The majority of tissues expressed c-Met. In pts with higher c-Met expression, an increased ORR of > 30% was observed at efficacious doses (≥2.4 mg/kg). Activity was also seen at lower c-Met expression levels (10–15% ORR). Conclusions: ABBV-400 at 2.4 and 3.0 mg/kg Q3W has a tolerable and manageable safety profile, with promising antitumor activity. Long-term tolerability appears improved at 2.4 relative to 3.0 mg/kg, with higher relative dose intensity and generally lower TEAEs. The study is also evaluating ABBV-400 with bevacizumab in pts with CRC. Clinical trial information: NCT05029882 . [Table: see text]

Phase 1b study evaluating the efficacy and safety of ABBV-400, a c-Met–targeting antibody-drug conjugate, in select advanced solid tumor indications.

TPS3162 Background: c-Met (MET protein) is commonly overexpressed in a number of tumors, including hepatocellular carcinoma (HCC), pancreatic ductal adenocarcinoma (PDAC), biliary tract cancers (BTC), esophageal squamous cell carcinoma (ESCC), breast cancer (BC), and head and neck squamous cell carcinoma (HNSCC). Patients with c-Met–overexpressing tumors represent an underserved population, with the need for more effective c-Met–targeting therapies to become available. ABBV-400 is an antibody-drug conjugate, consisting of the c-Met–targeting antibody telisotuzumab conjugated to a potent topoisomerase 1 inhibitor payload. Initial results from the ongoing first-in-human study (NCT05029882) of ABBV-400 in patients with advanced solid tumors indicate a tolerable safety profile, with a maximum tolerated dose of 3 mg/kg once every 3 weeks (Q3W), and promising antitumor activity, with an overall response rate of 24.4% (1). Herein, we describe a signal-seeking study evaluating ABBV-400 treatment in patients with select solid tumors. Methods: Multicenter, open-label, phase 1 signal-seeking study(NCT06084481). Eligible patients (≥18 years) have confirmed locally advanced/metastatic disease measurable per RECIST v1.1 and Eastern Cooperative Oncology Group performance status ≤1. Approximately 220 patients are planned for enrollment across 7 cohorts (HCC, n=40; PDAC, n=40; BTC, n=20; ESCC, n=40; triple-negative BC, n=20; hormone receptor-positive/HER2-negative BC, n=20; HNSCC, n=40). The primary objectives are to assess efficacy and safety/tolerability of ABBV-400 in each tumor indication. Secondary objectives include the evaluation of pharmacokinetics (PK) and immunogenicity of ABBV-400. Pharmacodynamic (PD) and biomarker analyses are exploratory endpoints. Patients receive intravenous ABBV-400 at 3 mg/kg Q3W until disease progression, intolerable toxicity, or any other per-protocol discontinuation criteria. c-Met expression will be assessed retrospectively by immunohistochemistry. The maximum treatment duration is 2 years. Tumor assessments are performed at screening and every 6 weeks from the first dose of study drug, with objective response rate as primary efficacy endpoint and duration of response, clinical benefit rate, progression-free survival, and overall survival as secondary efficacy endpoints. Safety evaluations include adverse events monitoring (graded according to the NCI CTCAE, v5.0), physical examinations, vital sign measurements, ECG variables, and clinical laboratory testing. Blood samples for PK, PD, and biomarker analysis are collected at designated time points throughout the study. Enrollment started in November 2023. As of 19 January 2024, 24 patients have been enrolled. 1. Sharma et al. JCO 2023;41[16 suppl]:3015. Clinical trial information: NCT06084481 .

Topographic analysis of pancreatic cancer by TMA and digital spatial profiling reveals biological complexity with potential therapeutic implications

Pancreatic ductal adenocarcinoma (PDAC) remains one of the most lethal human malignancies. Tissue microarrays (TMA) are an established method of high throughput biomarker interrogation in tissues but may not capture histological features of cancer with potential biological relevance. Topographic TMAs (T-TMAs) representing pathophysiological hallmarks of cancer were constructed from representative, retrospective PDAC diagnostic material, including 72 individual core tissue samples. The T-TMA was interrogated with tissue hybridization-based experiments to confirm the accuracy of the topographic sampling, expression of pro-tumourigenic and immune mediators of cancer, totalling more than 750 individual biomarker analyses. A custom designed Next Generation Sequencing (NGS) panel and a spatial distribution-specific transcriptomic evaluation were also employed. The morphological choice of the pathophysiological hallmarks of cancer was confirmed by protein-specific expression. Quantitative analysis identified topography-specific patterns of expression in the IDO/TGF-β axis; with a heterogeneous relationship of inflammation and desmoplasia across hallmark areas and a general but variable protein and gene expression of c-MET. NGS results highlighted underlying genetic heterogeneity within samples, which may have a confounding influence on the expression of a particular biomarker. T-TMAs, integrated with quantitative biomarker digital scoring, are useful tools to identify hallmark specific expression of biomarkers in pancreatic cancer.

AHNAK2 Promotes the Progression of Pancreatic Ductal Adenocarcinoma by Maintaining the Stability of c-MET.

Pancreatic ductal adenocarcinoma (PDAC) is extremely malignant and rapidly progresses. The overall response rate of PDAC to current treatment methods is still unsatisfactory. Thus, identifying novel targets and clarifying the underlying mechanisms associated with PDAC progression may potentially offer additional treatment strategies. AHNAK2 is aberrantly expressed in a variety of tumors and exerts pro-tumorigenic effects. However, the biological role of AHNAK2 in PDAC remains poorly understood. The expression of AHNAK2 in PDAC and paired non-tumor tissues was detected by immunohistochemistry (IHC) and quantitative real-time polymerase chain reaction (qRT-PCR). Lentivirus knockdown was performed to investigate the impact of AHNAK2 on the biological function of pancreatic cancer cells. The subcutaneous cell-derived xenograft (CDX) model and the KPC spontaneous mouse model with AHNAK2 silencing were used to observe the effects of AHNAK2 on tumor growth and prognosis. The expression of c-MET at protein level in response to HGF treatment was assessed using western blot. Our results demonstrated that AHNAK2 was highly expressed in PDAC clinical samples and associated with poor prognosis. Knockdown of AHNAK2 significantly inhibited the proliferation, migration, and invasion of pancreatic cancer cells. AHNAK2 knockdown or knockout resulted in tumor growth suppression and prolonged survival in mice with PDAC. In addition, AHNAK2 and c-MET expression levels showed a significant positive correlation at the post-transcriptional level. Mechanistically, AHNAK2 promoted tumor progression by preventing c-MET degradation and persistently activating the HGF/c-MET signaling pathway. Overall, our study revealed that AHNAK2 plays an important role in PDAC progression by modulating the c-MET signaling pathway, and targeting AHNAK2 may be an effective therapeutic strategy for PDAC.

Abstract LB043: VBC101-F11: An innovative EGFR/cMet bispecific antibody drug conjugate (ADC) targeting key oncogenic drivers in solid tumors

Abstract EGFR and cMet are two classic growth factor receptors frequently co-expressed in solid tumors at significantly high levels, while only limited to moderate expression in normal tissues. Beyond their co-expression patten, the aberrant or over expression in their pathway are implicated in oncogenesis. Notably, MET pathway activation either through increased cMet expression or its ligand, is often associated with resistance to EGFR tyrosine kinase inhibitors (TKI). Therefore, the interplay between EGFR and cMet, coupled with their differential expression in tumors versus normal tissue substantiates the rationale for a bispecific approach that targets both receptors to enhance tumor specificity. VBC101-F11 is a bispecific anti-EGFR/cMet ADC engineered to deliver clinically validated cytotoxic agents to tumor cells with a drug-to antibody ratio (DAR) of 4. This innovative design distinguishes VBC101-F11 from other EGFR/cMet-targeting agents on the market or in clinical trials (ABBV399 or AZD9592), optimizing both efficacy and safety. 1. VBC101-F11 features a low-affinity EGFR arm coupled with a high-affinity cMet arm. Incorporating the low-affinity EGFR arm enhances binding avidity and internalization, resulting in a superior cytotoxicity with a 5-fold improvement in IC50 compared to ABBV-399 (targeting cMet only). This nuanced EGFR arm design ensures a reduction in EGFR-related off-target toxicity in normal tissues. 2. The biparatopic design in cMet arm further underscores our strategic rationale by demonstrating a synergistic effect in terms of binding, internalization, and functional blocking with a 10-fold improvement in EC50 compared to the monospecific parental antibodies that target a single epitope. This ensures VBC101-F11’s maximized efficacy in tumor cells. 3. VBC101-F11’s innovative nanobody-based format sets our molecule apart. Living imaging data in mouse model reveals that VBC101-F11 (90kD) achieves superior tumor penetration and accumulation from 1 hour to over 90 hours surpassing the mAb ABBV399 and bispecific antibody AZD9592, both at 150kD. 4. VBC101-F11 has demonstrated outstanding molecular developability in stress tests, particularly in human and non-human primate (NHP) plasma, where both the antibody component and the entire ADC molecule exhibit remarkable stability, positioning VBC101-F11 as a viable candidate for future Chemistry, Manufacturing, and Controls (CMC) development. 5. In in vivo CDX models using various lung cancer cell lines, VBC101-F11 equipped with MMAE warhead displayed a marked superiority in tumor growth inhibition (TGI of 60% vs. 17%) at a single dose of 3mg/kg compared to MMAE conjugating ADC ABBV-399. Further payload exploration, such as DNA replication inhibitor, has also yielded promising results, with VBC101-F11-new payload showing comparable efficacy to the same class ADC AZD9592 in models with low EGFR and high cMet expression (100% TGI) and in those with moderate EGFR/cMet expression (~ 60% TGI). In summary, VBC101-F11, with unique design and distinguished attributes, has demonstrated its remarkable potential in the landscape of anti-EGFR/cMet therapies. The encouraging efficacy observed in preclinical models supports the molecule’s advancement into clinical development, positioning it as a best-in-class bispecific ADC for treating tumors in patients. Citation Format: Wei (Vivian) Wang, Jing Li, Lin Ma, Man Xu, Qun Yin. VBC101-F11: An innovative EGFR/cMet bispecific antibody drug conjugate (ADC) targeting key oncogenic drivers in solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB043.

Abstract LB025: CKD-703, a novel antibody-drug conjugate targeting cMET with an enhanced therapeutic index in solid tumors

Abstract In our pursuit of advancing cancer therapeutics, we introduce CKD-703, a groundbreaking cMET-targeting antibody drug conjugate (ADC) designed to strategically address the challenges posed by cMET overexpression and alteration in various solid tumors. Recognizing the pivotal role of tolerability and efficacy in shaping the therapeutic landscape of ADC, CKD-703 represents a significant advancement, aiming to widen the therapeutic index of cMET-targeted therapies. As we develop CKD-703, an innovative cMET-targeting ADC, we acknowledge the oncogenic potential of cMET alterations, particularly in non-small cell lung cancer (NSCLC), and the prevalent elevation of cMET across various cancers. Antibody drug conjugates targeting cMET (cMET-ADCs) have shown its therapeutic potential in treating cMET positive tumors, irrespective of their dependency on cMET signaling. Clinical success, however, has often been limited to NSCLC patients with the highest cMET levels. In light of this, CKD-703 is crafted to not only improve tolerability but also enhance efficacy, thereby broadening its application to a diverse patient population, including those with moderate cMET expression. To develop a novel cMET-ADC, Chong Kun Dang leverages Synaffix's ADC platform technology, incorporating glycan remodeling to achieve site-specific conjugation of the linker-payload to the antibody and ensuring a homogeneous drug-antibody ratio. These unique characteristics enhance CKD-703's stability in the bloodstream, minimizing the concentration of liberated free payload and significantly improving tolerability. The uniform DAR of CKD-703 contributes to improved pharmacokinetics, ensuring a consistent and sustained therapeutic effect. In comparison to benchmark antibodies, CKD-703 exhibits superior binding affinity to cMET and efficient internalization, resulting in enhanced therapeutic efficacy. This is evidenced in preclinical experiments which performed in several animal models that can mimic the complexities of cMET positive tumors with varying expression levels. The GLP toxicity studies of CKD-703 are ongoing. In conclusion, CKD-703 is a novel cMET-targeting ADC designed to overcome the limitations observed in existing cMET-ADCs in clinical trials as well as significantly improve tolerability and efficacy. By strategically addressing challenges associated with moderate cMET expression levels, CKD-703 emerges as a promising therapeutic candidate, aiming to broaden the therapeutic index in cMET-overexpressing solid tumors. This study highlights the importance of tailored approaches to diverse patient populations in advancing the development of CKD-703 in the pursuit of precision cancer therapies. Citation Format: Kwanwoo Lee, Sue-Youn Kim, Hye-Jin Hong, Eunjeong Park, Jungok Park, Seong-Ho Hong, Daekwon Bae, Nina Ha, Sohn-Ji Yeon, Inchang Hwang, Semi Kim, Yoonseok Lee, Ju-Hee Lee. CKD-703, a novel antibody-drug conjugate targeting cMET with an enhanced therapeutic index in solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB025.

Abstract 4555: c-Met/AXL crosstalk in mediating therapeutic resistance in renal cell carcinoma

Abstract Receptor Tyrosine Kinase (RTK), c-Met, is overexpressed in renal cancer and correlates with a decreased survival rate. Upon binding with its specific ligand, Hepatocyte Growth Factor (HGF), c-Met activates pro-tumorigenic signaling. c-Met/RTK inhibitors are used for the treatment of advanced renal cell carcinoma (RCC). However, acquired therapeutic resistance is a major clinical problem and the underlying mechanisms are largely unknown. Hence, novel therapeutic targets are needed to overcome the clinical hurdles; and the RTK, AXL, can be a potential target. AXL is overexpressed and a poor prognostic marker in RCC. AXL overexpression drives wide-ranging processes, including epithelial-to-mesenchymal transition (EMT), tumor angiogenesis, and resistance to chemotherapeutics. Cabozantinib (XL184/Cabo), is approved for advanced-stage RCC and can inhibit c-Met and VEGFR2 activation (including AXL and a few other RTKs); however, it is not a specific/potent inhibitor of AXL. Hence, inhibiting c-Met alone may not be sufficient when AXL remains active. Therefore, the pro-tumorigenic role of AXL and its cross-talk with c-Met in renal cancer need to be thoroughly investigated. We compared the expression of c-Met and AXL in TCGA and found significantly high expression of both c-Met and AXL in primary renal tumor tissues compared to normal tissues. Our data showed that AXL forms a complex with c-Met and may have a significant cross-talk which can be involved in therapeutic resistance. We have also found that prolonged treatment of c-Met inhibitor Cabo, (including Crizotinib and PF-4217903) induced c-Met and AXL overexpression in RCC cells. Interestingly, c-Met inhibitor(s)-induced overexpressed c-Met can also be increasingly phosphorylated (at low concentrations) in the presence of HGF, which may cause enhanced downstream tumor-promoting signaling. To understand the role of AXL in tumor-promoting pathways and therapeutic resistance, we have generated CRISPR/Cas9-mediated AXL knock-out cells (AXL-KO) and found that silencing AXL can prevent c-Met-inhibitor(s)-mediated c-Met overexpression. Furthermore, to identify the effect of AXL-KO on pro-tumorigenic signaling, transcriptional profiles of control clones and AXL-KO cells were compared. The gene set enrichment analysis (GSEA) showed that genes involved in ‘EMT’, ‘Hypoxia’, and ‘K-Ras’ signaling pathways were significantly downregulated. We have also utilized an AXL-specific small molecule inhibitor, TP-0903, in combination with Cabo and validated our data. We have also generated a Cabo-resistant cell line (Caki-1) and found high expression of c-Met and AXL in these cells. Furthermore, either silencing of AXL (using siRNA) or inhibiting AXL (using TP0903) induced significant apoptosis in these Cabo-resistant cells. Together, our data suggest that inhibition of AXL along with c-Met can be beneficial in preventing acquired therapeutic resistance in RCC. Citation Format: Akash Sabarwal, Laxminarayan Rawat, Johannes Wedel, Murugabaskar Balan, Gwo-Shu Mary Lee, Toni K. Choueiri, Soumitro Pal. c-Met/AXL crosstalk in mediating therapeutic resistance in renal cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4555.

Abstract 1907: MYTX-011: A pH-dependent anti-cMET ADC with increased payload delivery in vivo and potent activity against cMET-expressing tumors of various epithelial origins

Abstract cMET is an oncogenic receptor tyrosine kinase overexpressed in multiple types of solid tumors, including non-small cell lung cancer (NSCLC), gastric, head and neck, liver cancer and others. Several cMET-directed therapies including antibody-drug conjugates (ADCs) have been developed that may benefit a subset of patients with tumors that have high cMET expression, MET amplification, or dependency on cMET signaling. MYTX-011 is an investigational, pH-sensitive, vcMMAE-based ADC that is designed to potentially benefit not only patients whose tumors express high levels of cMET, but also a broader set of patients whose tumors express low to moderate levels of cMET. MYTX-011 is engineered to rapidly dissociate from cMET only at the acidic pH of endolysosomes. We have previously demonstrated that MYTX-011 drives increased internalization and cytotoxicity in tumor cells expressing moderate cMET levels compared to a matched parent non-pH sensitive ADC. MYTX-011 also demonstrated markedly superior efficacy in NSCLC xenografts with moderate cMET expression as compared to either the parent ADC or benchmark ADCs representing clinical-stage anti-cMET ADCs with vcMMAE and maytansinoid payloads. MYTX-011 was efficacious in NSCLC PDX models with moderate cMET expression of adenocarcinoma/squamous histology and in heterogeneous cMET-expressing EGFR mutant models. In these studies, we demonstrate that MYTX-011 exerts enhanced efficacy by delivering increased levels of payload to cMET+ tumors compared to the parent ADC. MYTX-011 treatment induced significantly increased levels of phospho-histone H3 (pHH3), a pharmacodynamic marker of MMAE cytotoxicity, in moderate cMET expressing NCI-H1975 NSCLC xenograft tumors compared to the parent ADC. Further, increased levels of free MMAE were detected in tumors from mice treated with MYTX-011 compared to a matched dose of the parent ADC, indicating that the pH dependent binding engineered into MYTX-011 translated to increased payload delivery to tumors in vivo. To explore the potential efficacy of MYTX-011 in other cMET-expressing tumor types, we tested the activity of MYTX-011 in a panel of cell lines derived from gastric and head and neck cancers. MYTX-011 demonstrated increased cMET-dependent cytotoxicity compared to the parent ADC. MYTX-011 was also highly active in cMET+ xenograft models derived from gastric (non-MET amplified), esophageal, and head and neck cancers. Together, these findings highlight the potential of MYTX-011 as a therapeutic candidate for treating a broader range of cMET-expressing malignancies. Citation Format: Deepak Kanojia, William Comb, William Israelsen, Federico Colombo, Lin Nie, Nimish Gera, Thomas Chittenden, Brian Fiske. MYTX-011: A pH-dependent anti-cMET ADC with increased payload delivery in vivo and potent activity against cMET-expressing tumors of various epithelial origins [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1907.