Acquired MET D1228N Mutations Mediate Crizotinib Resistance in Lung Adenocarcinoma with ROS1 Fusion: A Case Report

Progress of non-small-cell lung cancer with ROS1 rearrangement

ROS1 rearrangement is found in 0.9%-2.6% of people with non-small-cell lung cancers (NSCLCs). Tyrosine kinase inhibitors (TKIs) target ROS1 and can block tumor growth and provide clinical benefits to patients. This review summarizes the current knowledge on ROS1 rearrangements in NSCLCs, including the mechanisms of ROS1 oncogenicity, epidemiology of ROS1-positive tumors, methods for detecting rearrangements, molecular characteristics, therapeutic agents, and mechanisms of drug resistance.

Durable response to amivantamab in treatment refractory NSCLC harboring EGFR and complex MET mutations: A case report

Targeted therapies have revolutionized treatment for metastatic non-small cell lung cancer (NSCLC) with oncogenic driver mutations. However, challenges arise in managing concurrent mutations and overcoming resistance. We present the case of a patient with epidermal growth factor receptor (EGFR) (L747_A750delinsP exon19 deletion) and mesenchymal-epithelial transition factor (MET) mutations (D1228H, D1228N, D1228Y, Y1230H, MET amplification) who achieved a durable response to amivantamab (14 months ongoing) after progression on multiple lines of therapy including platinum-based chemotherapy, EGFR tyrosine kinase inhibitors (TKI) and combination TKI and MET inhibitors. This case highlights the utility of longitudinal next-generation sequencing (NGS) testing to identify acquired resistance and the need for continued research into understanding mechanisms of resistance to help develop future treatment strategies.

Analysis of CD74 Occurrence in Oncogenic Fusion Proteins

CD74 is a type II cell surface receptor found to be highly expressed in several hematological and solid cancers, due to its ability to activate pathways associated with tumor cell survival and proliferation. Over the past 16 years, CD74 has emerged as a commonly detected fusion partner in multiple oncogenic fusion proteins. Studies have found CD74 fusion proteins in a range of cancers, including lung adenocarcinoma, inflammatory breast cancer, and pediatric acute lymphoblastic leukemia. To date, there are five known CD74 fusion proteins, CD74-ROS1, CD74-NTRK1, CD74-NRG1, CD74-NRG2α, and CD74-PDGFRB, with a total of 16 different variants, each with unique genetic signatures. Importantly, the occurrence of CD74 in the formation of fusion proteins has not been well explored despite the fact that ROS1 and NRG1 families utilize CD74 as the primary partner for the formation of oncogenic fusions. Fusion proteins known to be oncogenic drivers, including those of CD74, are typically detected and targeted after standard chemotherapeutic plans fail and the disease relapses. The analysis reported herein provides insights into the early intervention of CD74 fusions and highlights the need for improved routine assessment methods so that targeted therapies can be applied while they are most effective.

Targeting MET: Discovery of Small Molecule Inhibitors as Non-Small Cell Lung Cancer Therapy

MET has been considered as a promising drug target for the treatment of MET-dependent diseases, particularly non-small cell lung cancer (NSCLC). Small molecule MET inhibitors with mainly three types of binding modes (Ia/Ib, II, and III) have been developed. In this Review, we provide an overview of the structural features, activation mechanism, and dysregulation pathway of MET and summarize progress on the development and discovery strategies utilized for MET inhibitors as well as mechanisms of acquired resistance to current approved inhibitors. The insights will accelerate discovery of new generation MET inhibitors to overcome clinical acquired resistance.

A pharmacological exploration of targeted drug therapy in non-small cell lung cancer

Lung cancer is the prime cause of cancer-related deaths globally, with a contribution of 85% from non-small cell lung cancer. Before a few decades back, conventional chemotherapy was the most chosen treatment option for NSCLC but with side effects. Now, the treatment approaches have shifted to a new trend, targeted therapy, and a better treatment strategy with minimal side effects compared to chemotherapy. Advances in technologies and understanding the pathways lead to the discovery of new targets and through which it is possible to improve treatment outcomes and patient compliance. Unlike chemotherapy, targeted therapy focuses on the tumor cells and does not produce toxicity to healthy cells. The last two decades were very crucial in the development of many small molecules with the capability to target-specific proteins or genes in the disease progression pathway. Although the targeted therapy approach was a gemstone with many successful drugs for the treatment of NSCLC, various resistance mechanisms and activation of bypass signaling pathways put many of these drugs in the trash. In this review, we will discuss the major targeted proteins involved in NSCLC as well as the inhibitor drugs developed to target them for now and along with the future directions.

Foretinib can overcome common on-target resistance mutations after capmatinib/tepotinib treatment in NSCLCs with MET exon 14 skipping mutation

Background

Capmatinib and tepotinib are guideline-recommended front-line treatments for non-small-cell lung cancer (NSCLC) patients with MET exon 14 skipping mutations (METex14). However, the emergence of acquired resistance to capmatinib/tepotinib is almost inevitable partially due to D1228X or Y1230X secondary mutations of the MET. In this study, we explored agents that are active against both D1228X and Y1230X MET to propose an ideal sequential treatment after capmatinib/tepotinib treatment failure in NSCLC patients with METex14.

Methods

The inhibitory effects of 300 drugs, including 33 MET-TKIs, were screened in Ba/F3 cells carrying METex14 plus MET D1228A/Y secondary mutations. The screen revealed four-candidate type II MET-TKIs (altiratinib, CEP-40783, foretinib and sitravatinib). Therefore, we performed further growth inhibitory assays using these four MET-TKIs plus cabozantinib and merestinib in Ba/F3 cells carrying MET D1228A/E/G/H/N/V/Y or Y1230C/D/H/N/S secondary mutations. We also performed analyses using Hs746t cell models carrying METex14 (with mutant allele amplification) with/without D1228X or Y1230X in vitro and in vivo to confirm the findings. Furthermore, molecular dynamics (MD) simulations were carried out to examine differences in binding between type II MET-TKIs.

Results

All 6 type II MET-TKIs were active against Y1230X secondary mutations. However, among these 6 agents, only foretinib showed potent activity against D1228X secondary mutations of the MET in the Ba/F3 cell and Hs746t in vitro model and Hs746t in vivo model, and CEP-40783 and altiratinib demonstrated some activity. MD analysis suggested that the long tail of foretinib plays an important role in binding D1228X MET through interaction with a residue at the solvent front (G1163). Tertiary G1163X mutations, together with L1195F/I and F1200I/L, occurred as acquired resistance mechanisms to the second-line treatment foretinib in Ba/F3 cell models.

Conclusions

The type II MET-TKI foretinib may be an appropriate second-line treatment for NSCLCs carrying METex14 after campatinib/tepotinib treatment failure by secondary mutations at residue D1228 or Y1230.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13045-022-01299-z.

ROS-1 Fusions in Non-Small-Cell Lung Cancer: Evidence to Date

The ROS-1 gene plays a major role in the oncogenesis of numerous tumors. ROS-1 rearrangement is found in 0.9–2.6% of non-small-cell lung cancers (NSCLCs), mostly lung adenocarcinomas, with a significantly higher rate of women, non-smokers, and a tendency to a younger age. It has been demonstrated that ROS-1 is a true oncogenic driver, and tyrosine kinase inhibitors (TKIs) targeting ROS-1 can block tumor growth and provide clinical benefit for the patient. Since 2016, crizotinib has been the first-line reference therapy, with two-thirds of the patients’ tumors responding and progression-free survival lasting ~20 months. More recently developed are ROS-1-targeting TKIs that are active against resistance mechanisms appearing under crizotinib and have better brain penetration. This review summarizes current knowledge on ROS-1 rearrangement in NSCLCs, including the mechanisms responsible for ROS-1 oncogenicity, epidemiology of ROS-1-positive tumors, methods for detecting rearrangement, phenotypic, histological, and molecular characteristics, and their therapeutic management. Much of this work is devoted to resistance mechanisms and the development of promising new molecules.

A rapid and durable response to cabozantinib in an osimertinib-resistant lung cancer patient with MET D1228N mutation: a case report

Osimertinib has efficacy superior to that of standard epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) for the first-line treatment of patients with EGFR-mutant advanced non-small cell lung cancer (NSCLC). However, patients treated with osimertinib eventually acquire drug resistance. MET missense mutations have been demonstrated to mediate resistance to MET-TKIs, such as crizotinib. But the role of MET missense mutations in mediating EGFR TKI resistance is undefined. With the increasing use of next-generation sequencing (NGS) at diagnosis, many mechanisms of acquired resistance have been discovered in patients with activated tyrosine kinase receptors. Herein, we report the first case of MET D1228N mutation mediating acquired resistance to osimertinib in a MET TKI-naïve NSCLC. The patient with advanced lung adenocarcinoma harboring EGFR exon 19 deletion initially responded to osimertinib with progression-free survival (PFS) lasting 11 months and then developed resistance with an acquired mutation of MET D1228N. Subsequently, combination therapy of cabozantinib and osimertinib was administrated to the patient, and her clinical symptoms were rapidly relieved within one week with good tolerance. She remained on the combined treatment for 10 months. Finally, she achieved an overall survival (OS) of 25 months. Based on our findings, patient with MET D1228N mutant lung adenocarcinoma clinically benefited from combinatorial therapy of cabozantinib and osimertinib after osimertinib resistance.

MET D1228N and D1246N are the Same Resistance Mutation in MET Exon 14 Skipping

Comprehensive genetic profiling using next-generation sequencing technologies has become an integral part of precision oncology. Variant annotation requires translating the DNA findings into protein level predictions. In this article we highlight inconsistencies in variant annotation for the MET D1228N exon 19 resistance mutations. MET D1228N and D1246N represent the same resistance mutation in MET exon 14 skipping alterations annotated on different transcripts. Additional examples of relevant variants annotated on different transcripts emphasize the importance of avoiding erroneous interpretation when realizing precision oncology.

HGF/c-MET pathway in cancer: from molecular characterization to clinical evidence

This review provides a comprehensive landscape of HGF/c-MET (hepatocyte growth factor (HGF) /mesenchymal-epithelial transition factor (c-MET)) signaling pathway in cancers. First, we generalize the compelling influence of HGF/c-MET pathway on multiple cellular processes. Then, we present the genomic characterization of HGF/c-MET pathway in carcinogenesis. Furthermore, we extensively illustrate the malignant biological behaviors of HGF/c-MET pathway in cancers, in which hyperactive HGF/c-MET signaling is considered as a hallmark. In addition, we investigate the current clinical trials of HGF/c-MET-targeted therapy in cancers. We find that although HGF/c-MET-targeted therapy has led to breakthroughs in certain cancers, monotherapy of targeting HGF/c-MET has failed to demonstrate significant clinical efficacy in most cancers. With the advantage of the combinations of HGF/c-MET-targeted therapy, the exploration of more options of combinational targeted therapy in cancers may be the major challenge in the future.

Case Report: High-Level MET Amplification as a Resistance Mechanism of ROS1-Tyrosine Kinase Inhibitors in ROS1-Rearranged Non-Small Cell Lung Cancer

Background

Although C-ros oncogene 1 (ROS1) targeted therapies have demonstrated remarkable efficacy in ROS1-rearranged non-small cell lung cancer (NSCLC), patients inevitably develop resistance to ROS1-tyrosine kinase inhibitors (TKIs). Commonly acquired resistance mechanisms include a second mutation of the ROS1 kinase domain and activation of bypass signaling pathways. However, MMNG HOS Transforming gene (MET) amplification has not been reported as a novel mechanism of ROS1-TKIs resistance.

Case Presentation

We report a case of a 62-year-old man diagnosed with ROS1-rearranged metastatic lung adenocarcinoma, who received first-line treatment with crizotinib for 19 months. During the course of disease, the primary lung tumor was under control while the brain metastasis progressed despite the treatment with lorlatinib. The biopsy and genetic tests of the metastatic brain tumor showed a high level of MET amplification (32 copies). However, fluorescence in situ hybridization of the primary cancer showed no MET amplification, suggesting that MET amplification may be associated with an acquired resistance to ROS1-TKIs.

Summary

This case suggested that MET amplification could be explored as a potential mechanism for developing ROS1-TKIs resistance. Combination treatment with highly potent and selective MET-TKIs warrants further investigations.