Genetic landscape of patients with ALK-rearranged non-small-cell lung cancer (NSCLC) and response to ceritinib in ASCEND-1 study

A Poor Prognostic ALK Phenotype: A Review of Molecular Markers of Poor Prognosis in ALK Rearranged Nonsmall Cell Lung Cancer

BACKGROUND

Patients with nonsmall cell lung cancer with anaplastic lymphoma kinase (ALK) rearrangements derive a significant and durable clinical benefit from tyrosine kinase inhibitors (TKIs). However, early progression/death on treatment occurs in a subset of patients, which we term the poor prognostic ALK phenotype. This review aims to summarize the known molecular mechanisms that underlie this phenotype with a focus on variant 3 and TP53 mutations.

METHODS

A scoping review was performed using scientific databases such as Ovid Medline, Ovid Embase, and Cochrane Central Register of Controlled Trials. Studies included molecular markers of poor prognosis, with a focus on TP53 mutations, variant 3 re-arrangements, and poor clinical response to TKIs.

RESULTS

Of 4371 studies screened, 108 were included. Numerous studies implicated a negative prognostic role of variant 3, likely mediated through the acquisition of on-target resistance mutations and TP53 mutations which are associated with greater chromosomal instability and mutational burden. Co-occurring variant 3 and TP53 mutations were associated with even worse survival. Other mediators of early resistance development include aberrations in cell cycle regulators and mutations in cell signaling pathways. Comprehensive genomic analysis from first-line TKI clinical trial data was unable to identify a singular genomic signature that underlies the poor prognostic phenotype but implicated a combination of pathways.

CONCLUSIONS

This scoping review highlights that the poor prognostic ALK phenotype is likely composed of a heterogeneous variety of genomic factors. There remains an unmet need for a genomic assay to integrate these various molecular markers to predict this ALK phenotype.

Unraveling the Potential of ALK-Targeted Therapies in Non-Small Cell Lung Cancer: Comprehensive Insights and Future Directions

Background and Objective: This review comprehensively explores the intricate landscape of anaplastic lymphoma kinase (ALK), focusing specifically on its pivotal role in non-small cell lung cancer (NSCLC). Tracing ALK's discovery, from its fusion with nucleolar phosphoprotein (NPM)-1 in anaplastic large cell non-Hodgkin's lymphoma (ALCL) in 1994, the review elucidates the subsequent impact of ALK gene alterations in various malignancies, including inflammatory myofibroblastoma and NSCLC. Approximately 3-5% of NSCLC patients exhibit complex ALK rearrangements, leading to the approval of six ALK-tyrosine kinase inhibitors (TKIs) by 2022, revolutionizing the treatment landscape for advanced metastatic ALK + NSCLC. Notably, second-generation TKIs such as alectinib, ceritinib, and brigatinib have emerged to address resistance issues initially associated with the pioneer ALK-TKI, crizotinib. Methods: To ensure comprehensiveness, we extensively reviewed clinical trials on ALK inhibitors for NSCLC by 2023. Additionally, we systematically searched PubMed, prioritizing studies where the terms "ALK" AND "non-small cell lung cancer" AND/OR "NSCLC" featured prominently in the titles. This approach aimed to encompass a spectrum of relevant research studies, ensuring our review incorporates the latest and most pertinent information on innovative and alternative therapeutics for ALK + NSCLC. Key Content and Findings: Beyond exploring the intricate details of ALK structure and signaling, the review explores the convergence of ALK-targeted therapy and immunotherapy, investigating the potential of immune checkpoint inhibitors in ALK-altered NSCLC tumors. Despite encouraging preclinical data, challenges observed in trials assessing combinations such as nivolumab-crizotinib, mainly due to severe hepatic toxicity, emphasize the necessity for cautious exploration of these novel approaches. Additionally, the review explores innovative directions such as ALK molecular diagnostics, ALK vaccines, and biosensors, shedding light on their promising potential within ALK-driven cancers. Conclusions: This comprehensive analysis covers molecular mechanisms, therapeutic strategies, and immune interactions associated with ALK-rearranged NSCLC. As a pivotal resource, the review guides future research and therapeutic interventions in ALK-targeted therapy for NSCLC.

Prediction of Resistance Mutations Against Upcoming Anaplastic Lymphoma Kinase Inhibitors

BACKGROUND

Chromosomal aberrations involving the anaplastic lymphoma kinase (ALK) gene have been observed in approximately 4% of patients with non-small cell lung cancer (NSCLC). Although these patients clinically benefit from treatment with various ALK tyrosine kinase inhibitors (ALK-TKIs), none of these can inhibit the development of resistance mutations. Considering inevitable drug resistance and the variety of available ALK-TKIs, it is necessary to predict the pattern of drug-resistance mutations to determine the optimal treatment strategy.

OBJECTIVE

We aimed to establish a polymerase chain reaction (PCR)-based system to predict the development of resistance mutations against ALK-TKIs and identify therapeutic strategies using the upcoming ALK-TKIs repotrectinib (TPX-0005) and ensartinib (X-396) following recurrence on first-line alectinib treatment for ALK-positive NSCLC.

METHODS

An error-prone PCR-based method for predicting drug resistance mutations was established and the half-maximal inhibitory concentration (IC₅₀) values of the predicted ALK mutations were evaluated in a Ba/F3 cell-based assay.

RESULTS

We predicted several resistance mutations against repotrectinib and ensartinib, and demonstrated that the next-generation ALK-TKI TPX-0131, was active against repotrectinib-resistant mutations and that the FLT3 inhibitor gilteritinib was active against ensartinib-resistant mutations.

CONCLUSIONS

We developed a PCR-based system for predicting drug resistance mutations. When this system was applied to repotrectinib and ensartinib, the results suggested that these drugs can be used for the second-line treatment of ALK-positive NSCLC. Predicting resistance mutations against TKIs will provide useful information to aid in the development of effective therapeutic strategies.

Identification of a novel RMST-ALK rearrangement in advanced lung adenocarcinoma and durable response to ceritinib: A case report

Next-generation sequencing technology has enabled the identification of fusion partners of anaplastic lymphoma kinase (ALK) in non-small cell lung cancer, and various ALK fusion partners have been confirmed. Here, a novel rhabdomyosarcoma 2-associated transcript (RMST)-ALK rearrangement was identified in an 80-year-old Chinese man with advanced lung adenocarcinoma. The patient was prescribed ceritinib and achieved a partial response, which has been sustained for more than 18 months. This is the first report of the RMST-ALK rearrangement, and we showed that a patient with lung adenocarcinoma carrying this rearrangement can benefit from ceritinib treatment; therefore, this is a significant finding in clinical practice.

Identification and therapeutic evaluation of ALK rearrangements in non-small-cell lung cancer

This study aimed to present a comprehensive assessment of anaplastic lymphoma kinase (ALK) rearrangements evaluated by DNA/RNA-based next-generation sequencing (NGS) and Ventana immunohistochemistry (IHC) in patients with non-small-cell lung cancer (NSCLC) and to evaluate the therapeutic outcomes of ALK tyrosine kinase inhibitor (TKI) treatment. We investigated ALK gene fusions in 14,894 patients with NSCLC using Ventana IHC and NGS, including 12,533 cases detected via DNA-based NGS and 2,361 cases using RNA-based NGS. The overall percentage agreement (OPA), positive percentage agreement (PPA), and negative percentage agreement (NPA) were calculated when comparing the results between NGS and IHC. The therapeutic responses to ALK-TKIs were also evaluated. In total, 3.50% (439/12,533) of specimens were NGS ALK-positive (NGS-p) in the DNA-based NGS cohort and 3.63% (455/12,533) were IHC ALK-positive (IHC-p). The OPA of NGS was 99.60%, whereas its PPA and NPA were 92.75 and 99.86%, respectively. In the adenocarcinoma (ADC) subcohort, the PPA was 95.69%. In the RNA-based NGS cohort, 2.20% (52/2,361) of specimens were NGS-p and 2.63% (62/2,361) were IHC-p. The OPA of NGS was 99.49%; its PPA and NPA were 82.26 and 99.96%, respectively. Thirteen patients with discordant results received ALK-TKI treatment. In the seven NGS-p/IHC-negative (IHC-n) patients, the overall response rate (ORR) was 85.4% (6/7) and the disease control rate (DCR) was 100%. In the six NGS-negative/IHC-p patients, the ORR was 66.7% (4/6) and the DCR was 100%. In summary, a high concordance of ALK gene fusion detected via NGS and IHC was observed in this study. DNA-based NGS had a higher OPA, PPA, and PPA in the ADC subcohort, whereas RNA-based NGS had a higher NPA. Overall, the results suggest that the combination of NGS and IHC can improve the accuracy of ALK fusion detection; hence, a result determination algorithm for clinical detection of ALK gene fusion was also proposed.