Clinical Implications of the BIM Deletion Polymorphism in Advanced Lung Adenocarcinoma Treated With Gefitinib

Metastatic pulmonary carcinoids with EML4-ALK fusion response to ALK inhibitors: two case reports and review of literature

Background

Pulmonary carcinoids (PC), including typical (TC) and atypical carcinoids (AC), are low-grade neuroendocrine tumors (NETs) which account for 1–5% of all lung tumors. Due to the low prevalence of PC and extreme rarity of anaplastic lymphoma kinase (ALK) rearrangements in patients with PC, the advances in targeted therapy development in PC are still limited and there is no standard treatment. Even though in patients with PC harboring ALK rearrangements there is a room for a success in targeted therapy. To our knowledge, case 1 was the first report to detect ALK gene p.I1171N mutation after taking alectinib and sensitive to ceritinib in patients with atypical carcinoid.

Case Description

Herein, we report the cases of 2 non-smoking patients, 51 year-old female with tumor in left lower lobe and 49 year-old female with tumor in right upper lobe, both with metastatic PC who harbored EML4-ALK fusion and were sensitive to small-molecule ALK inhibitors. The first patient initially received alectinib, then therapy was switched to ceritinib after developing drug resistance due to the missense mutation of ALK gene p.I1171N mutation in exon 22 detected by next-generation sequencing (NGS), and finally died of intracranial disease progression. The second patient also received alectinib, and her treatment is currently ongoing with good effect and tolerance. After conducting comprehensive review of literature, we found that 14 lung NETs with ALK rearrangements have been reported to date. The clinical outcome was partial response for 6 NETs patients and 5 patients exhibited stable disease after treatment with ALK inhibitors.

Conclusions

According to the effectiveness of ALK inhibitors in our cases and previous articles, we recommend alectinib for the first-line treatment of metastatic PC with EML4-ALK fusion and highlight the need for molecular profiling of metastatic lung NETs patients and that ALK inhibitors are feasible in the treatment for metastatic lung NETs patients with ALK rearrangements. Finally, further studies to assess the real prevalence of ALK gene fusions and their spectrum of sensitivity to different ALK inhibitors are needed in larger cohorts.

Prognostic Value of BIM Deletion in EGFR-Mutant NSCLC Patients Treated with EGFR-TKIs: A Meta-Analysis

BACKGROUND

Resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) is inevitable in EGFR-mutant non-small-cell lung cancer (NSCLC) patients. A germline 2903 bp deletion polymorphism of Bcl-2-like protein 11 (BIM) causes reduced expression of proapoptotic BH3-only BIM protein and blocks TKI-induced apoptosis of tumor cells. Yet the association between the deletion polymorphism and response to EGFR-TKI treatment remains inconsistent among clinical observations. Thus, we performed the present meta-analysis.

METHODS

Eligible studies were identified by searching PubMed, Embase, and ClinicalTrials.gov databases prior to March 31, 2021. Hazard ratios (HRs) and 95% confidence intervals (CIs) of progression-free survival (PFS) and overall survival (OS) and odds ratios (ORs) and 95% CIs of objective response rate (ORR) and disease control rate (DCR) were calculated by using a random effects model. Sensitivity, metaregression, and publication bias analyses were also performed.

RESULTS

A total of 20 datasets (3003 EGFR-mutant NSCLC patients receiving EGFR-TKIs from 18 studies) were included. There were 475 (15.8%) patients having the 2903-bp intron deletion of BIM and 2528 (84.2%) wild-type patients. BIM deletion predicted significantly shorter PFS (HR = 1.35, 95% CI: 1.10-1.64, P = 0.003) and a tendency toward an unfavorable OS (HR = 1.22, 95% CI: 0.99-1.50, P = 0.068). Patients with deletion polymorphism had lower ORR (OR = 0.60, 95% CI: 0.42-0.85, P = 0.004) and DCR (OR = 0.59, 95% CI: 0.38-0.90, P = 0.014) compared with those without deletion.

CONCLUSION

BIM deletion polymorphism may confer resistance to EGFR-TKIs and can be used as a biomarker to predict treatment response to EGFR-TKIs in EGFR-mutant NSCLC patients from Asian populations.

Oncogene HSPH1 modulated by the rs2280059 genetic variant diminishes EGFR-TKIs efficiency in advanced lung adenocarcinoma

Although epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) therapy is effective for most advanced non-small-cell lung cancer (NSCLC) patients with mutant EGFR, some patients show little or no response. Germline variations, such as single-nucleotide polymorphisms (SNPs), have been proved to be involved in disease progression after EGFR-TKI therapy. In this study, we hypothesized that the functional HSPH1 SNP may affect gene expression and, thus, prognosis of NSCLC patients treated with EGFR-TKIs. We systematically examined impacts of HSPH1 SNPs on NSCLC survival in two independent cohorts consisted of 319 EGFR-TKI treated stage IIIB/IV NSCLC patients. The promoter rs2280059 polymorphism was significantly associated with patient survival in both cohorts. In vitro and In vivo assays elucidated that rs2280059 G allele shows higher capability to drive HSPH1 promoter activities. Silencing HSPH1 significantly increases the antineoplastic effects of gefitinib on NSCLC cells. Our findings demonstrated potential implications of HSPH1 in clinic, which may lead to better understanding and outcome assessment of EGFR-TKI treatment.

Efficacy of EGFR tyrosine kinase inhibitors in patients having EGFR-activating mutations with or without BIM polymorphisms

PURPOSE

Patients with epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer with BIM deletion polymorphism may have a limited response to EGFR tyrosine kinase inhibitors (EGFR-TKIs). However, some results of previous reports are discordant. It is necessary to evaluate the relationship between BIM polymorphism and the efficacy of EGFR-TKIs.

METHODS

We retrospectively analyzed patients treated with EGFR-TKIs. We collected serum samples from patients before EGFR-TKI administration. We analyzed BIM deletion polymorphism and BIM single nucleotide polymorphism in exon 5 c465C > T by the Invader^® assay.

RESULTS

BIM deletion polymorphism was identified in 27 of 194 patients (13.9%). BIM single nucleotide polymorphism was identified in 29 of 194 patients (14.9%). The overall response ratio was 81.5% in patients with BIM deletion polymorphism, 89.7% with BIM single nucleotide polymorphism, and 83.6% with BIM wild type. Median progression-free survival was 10.3 months with BIM deletion polymorphism, 8.5 months with BIM single nucleotide polymorphism, and 10.4 months with BIM wild type. Overall survival was 38.4 months with BIM deletion polymorphism, 29.1 months with BIM single nucleotide polymorphism, and 31.6 months with BIM wild type. There were no significant differences between the groups in overall response ratio, progression-free survival, and overall survival.

CONCLUSIONS

BIM polymorphism does not affect EGFR-TKI efficacy.

Hypoxia Induces Resistance to EGFR Inhibitors in Lung Cancer Cells via Upregulation of FGFR1 and the MAPK Pathway

Development of resistance remains the key obstacle to the clinical efficacy of EGFR tyrosine kinase inhibitors (TKI). Hypoxia is a key microenvironmental stress in solid tumors associated with acquired resistance to conventional therapy. Consistent with our previous studies, we show here that long-term, moderate hypoxia promotes resistance to the EGFR TKI osimertinib (AZD9291) in the non-small cell lung cancer (NSCLC) cell line H1975, which harbors two EGFR mutations including T790M. Hypoxia-induced resistance was associated with development of epithelial-mesenchymal transition (EMT) coordinated by increased expression of ZEB-1, an EMT activator. Hypoxia induced increased fibroblast growth factor receptor 1 (FGFR1) expression in NSCLC cell lines H1975, HCC827, and YLR086, and knockdown of FGFR1 attenuated hypoxia-induced EGFR TKI resistance in each line. Upregulated expression of FGFR1 by hypoxia was mediated through the MAPK pathway and attenuated induction of the proapoptotic factor BIM. Consistent with this, inhibition of FGFR1 function by the selective small-molecule inhibitor BGJ398 enhanced EGFR TKI sensitivity and promoted upregulation of BIM levels. Furthermore, inhibition of MEK activity by trametinib showed similar effects. In tumor xenografts in mice, treatment with either BGJ398 or trametinib enhanced response to AZD9291 and improved survival. These results suggest that hypoxia is a driving force for acquired resistance to EGFR TKIs through increased expression of FGFR1. The combination of EGFR TKI and FGFR1 or MEK inhibitors may offer an attractive therapeutic strategy for NSCLC. SIGNIFICANCE: Hypoxia-induced resistance to EGFR TKI is driven by overexpression of FGFR1 to sustain ERK signaling, where a subsequent combination of EGFR TKI with FGFR1 inhibitors or MEK inhibitors reverses this resistance. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/21/4655/F1.large.jpg.

Targeting apoptosis in cancer therapy

For over three decades, a mainstay and goal of clinical oncology has been the development of therapies promoting the effective elimination of cancer cells by apoptosis. This programmed cell death process is mediated by several signalling pathways (referred to as intrinsic and extrinsic) triggered by multiple factors, including cellular stress, DNA damage and immune surveillance. The interaction of apoptosis pathways with other signalling mechanisms can also affect cell death. The clinical translation of effective pro-apoptotic agents involves drug discovery studies (addressing the bioavailability, stability, tumour penetration, toxicity profile in non-malignant tissues, drug interactions and off-target effects) as well as an understanding of tumour biology (including heterogeneity and evolution of resistant clones). While tumour cell death can result in response to therapy, the selection, growth and dissemination of resistant cells can ultimately be fatal. In this Review, we present the main apoptosis pathways and other signalling pathways that interact with them, and discuss actionable molecular targets, therapeutic agents in clinical translation and known mechanisms of resistance to these agents.

EGFR exon 20 insertion mutations in Chinese advanced non-small cell lung cancer patients: Molecular heterogeneity and treatment outcome from nationwide real-world study

OBJECTIVES

To describe the treatment patterns and outcomes of Chinese non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) exon 20 insertion (ex20ins) mutations in real-world as EGFR ex20ins consist of a diverse group of mutations with limited information on the clinical outcome of these patients treated with chemotherapy or EGFR tyrosine kinase inhibitors (TKIs).

MATERIALS AND METHODS

Real-world treatment outcomes of Chinese NSCLC patients harboring EGFR ex20ins were retrospectively analyzed based on medical records at different institutions and detailed web-based patient questionnaires.

RESULTS

Between March 17, 2018 and December 20, 2018, 165 advanced EGFR ex20ins NSCLC patients treated in 99 hospitals from 26 different regions in China were analyzed. Thirty-nine different molecular variants of EGFR ex20ins were identified with V769_D770insASV being the most common (23.0 %). Central nervous system (CNS) metastasis occurred in 23.0 % of patients at the time of baseline diagnosis. Median progression-free survival (PFS) was significantly longer in patients who received first-line platinum-based chemotherapy (6.4 m; 95 % CI: 5.7-7.1) than all-generation EGFR TKIs (2.9 m; 95 %CI: 1.5-4.3; P < 0.001) or 1st-generation EGFR TKIs (2.0 m; 95 %CI: 0.2-3.8; P < 0.001). Median PFS was numerically longer in patients who received second-line chemotherapy (4.0 m; 95 %CI: 3.2-4.8) than those received second-line EGFR TKIs (2.0 m; 95 %CI: 1.1-2.9; P = 0.342). Patients with CNS metastasis had numerically shorter median PFS than those without CNS metastasis when treated with 1st-line chemotherapy (3.6 m; 95 %CI: 0-8.0 vs. 6.5 m; 95 %CI: 4.9-8.1; P = 0.645) or 1st-line EGFR TKIs (2.0 m; 95 %CI: 0.8-3.2 vs. 2.9 m; 95 %CI: 2.1-3.7; P = 0.058).

CONCLUSION

Chemotherapy is superior to current approved EGFR TKIs as 1st- or 2nd-line treatment of EGFR ex20ins mutations. CNS metastasis conferred numerically shorter PFS with chemotherapy or EGFR TKIs treatment. Targeted agent against EGFR ex20ins with CNS activity is urgently needed.

DACT2 modulated by TFAP2A-mediated allelic transcription promotes EGFR-TKIs efficiency in advanced lung adenocarcinoma

Patients with epidermal growth factor receptor (EGFR)-mutant advanced non-small-cell lung cancer (NSCLC) benefits from EGFR-tyrosine kinase inhibitor (TKI) treatment. However, drug resistance to EGFR-TKIs remains a great challenge. Single nucleotide polymorphisms (SNPs) may significantly influence prognosis of EGFR-TKI therapy. Herein, we hypothesized that the functional SNP in DACT2, coding a pivotal inhibitor of the Wnt/β-catenin signaling, may affect gene expression, which in turn, impact prognosis of NSCLC treated with EGFR-TKIs. Genotypes of the DACT2 promoter rs9364433 SNP were determined in two independent cohorts consisted of 319 EGFR-TKI treated stage IIIB/IV NSCLC patients. The allele-specific regulation on DACT2 expression by rs9364433 and impacts of DACT2 on gefitinib sensitivity was evaluated in vitro and in vivo. Cox regression analyses demonstrated that rs9364433 was significantly associated with patient survival in both cohorts (all P < 0.05). Reporter gene assays and Electrophoretic Mobility Shift Assays demonstrated that rs9364433 has an allele-specific effect on gene expression modulated by transcription factor TFAP2A. The G allele associated with diminished TFAP2A binding leads to significantly decreased DACT2 expression in NSCLC cell lines and tissues. Consistently, DACT2 could evidently increase the anti-proliferation effect of gefitinib on NSCLC cells. Our findings elucidated potential clinical implications of DACT2, which may result in better understanding and outcome assessment of EGFR-TKI treatments.

Resistance to paclitaxel is associated with a variant of the gene BCL2 in multiple tumor types

Paclitaxel, the most commonly used form of chemotherapy, is utilized in curative protocols in different types of cancer. The response to treatment differs among patients. Biological interpretation of a mechanism to explain this personalized response is still unavailable. Since paclitaxel is known to target BCL2 and TUBB1, we used pan-cancer genomic data from hundreds of patients to show that a single-nucleotide variant in the BCL2 sequence can predict a patient’s response to paclitaxel. Here, we show a connection between this BCL2 genomic variant, its transcript structure, and protein abundance. We demonstrate these findings in silico, in vitro, in formalin-fixed paraffin-embedded (FFPE) tissue, and in patient lymphocytes. We show that tumors with the specific variant are more resistant to paclitaxel. We also show that tumor and normal cells with the variant express higher levels of BCL2 protein, a phenomenon that we validated in an independent cohort of patients. Our results indicate BCL2 sequence variations as determinants of chemotherapy resistance. The knowledge of individual BCL2 genomic sequences prior to the choice of chemotherapy may improve patient survival. The current work also demonstrates the benefit of community-wide, integrative omics data sources combined with in-lab experimentation and validation sets.

IL-37 promotes cell apoptosis in cervical cancer involving Bim upregulation

Background: Growing evidence has indicated that interleukin-37 (IL-37) is a potential anticancer molecule that mainly plays an inhibiting role in different kinds of cancers, but data for the role of IL-37 on cell apoptosis in cancers remains rare. The present study aimed to explore the role of IL-37 in cell apoptosis in cervical cancer, and the involved apoptosis-related molecules.

Methods: IL-37 was overexpressed by transfecting the pIRES2-EGFP-IL-37 plasmid in HeLa and C33A cells. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed to detect the mRNA expression of IL-37, Bcl-2, Bax and Bim. Western blotting was performed to detect the protein expression of IL-37 and Bim. Cell apoptosis was detected by flow cytometry.

Results: IL-37 upregulated the mRNA expression levels of Bim by 138.40% for HeLa (P<0.05) and 58.95% for C33A (P<0.05), and increased the protein expression levels of BimL by 69.10% (P<0.05) and 56.66% (P<0.05) in HeLa and C33A, respectively. Overexpression of IL-37 increased the apoptosis rates by 152.86% for HeLa (P<0.01) and 25.4% for C33A (P<0.05). Knockdown of Bim by specific siRNA interference fragments (SiBim) reduced the apoptosis rates by 36.00% for HeLa (P<0.05) and 14.66% for C33A (P<0.05). Compared with the IL-37 overexpression group, the apoptosis rate in cotransfecting the IL-37 overexpression plasmid and SiBim group decreased by approximately 31% (P<0.05) and 24.35% (P<0.05) in HeLa and C33A, respectively.

Conclusion: IL-37 upregulated Bim in cervical cancer cells. Furthermore, IL-37 can promote cervical cancer cell apoptosis, but Bim knockdown decreased this promotion through IL-37. Thus, IL-37 can promote cervical cancer cell apoptosis, which involve the upregulation of Bim.

miR-608 and miR-4513 significantly contribute to the prognosis of lung adenocarcinoma treated with EGFR-TKIs

Tyrosine kinase inhibitors (TKIs) targeting epidermal growth factor receptors (EGFR) significantly prolong the survival of lung adenocarcinoma patients with sensitizing EGFR mutations. Unfortunately, 10-30% patients do not show objective responses to EGFR-TKIs, and undergo rapid disease progression during the EGFR-TKIs therapy. Single nucleotide polymorphisms (SNPs) in mature microRNA (miRNA) sequences may influence target site interactions and modulate downstream pathways, such as the EGFR pathway. For this reason, we hypothesized that miRNA SNPs may impact the prognosis of lung adenocarcinoma patients after EGFR-TKI treatment. By systematically screening of the miRbase and the 1000 genomes project databases, we successfully identified five mature miRNA SNPs. Genotypes were determined in two independent cohorts (Hubei and Shandong cohorts) that include 319 EGFR-TKI treated stage IIIB/IV patients. The impact of miR-608 and miR-4513 on the drug sensitivity of gefitinib was examined in lung adenocarcinoma cells. miR-608 rs4919510 or miR-4513 rs2168518 significantly contributed to the progression-free survival (PFS) in the Hubei cohort (hazard ratio [HR] = 0.63, confidence interval [CI] = 0.49-0.81, P = 3.0 × 10^-4 or HR = 0.46, 95% CI = 0.31-0.67, P = 8.0 × 10^-5). These observations were further validated in the Shandong cohort (P = 0.005 or P = 0.001). Similarly, the miR-608 rs4919510 CC genotype or the miR-4513 rs2168518 GA genotype was significantly associated with decreased death risk after gefitinib treatment, compared with the rs4919510 GG genotype (Hubei cohort: P = 5.0 × 10^-4; Shandong cohort: P = 0.004) or the rs2168518 GG genotype (P = 4.9 × 10^-5; P = 0.002). Consistently, miR-608 significantly increased the anti-proliferation effect of gefitinib in both lung adenocarcinoma PC9 and H1299 cells, whereas miR-4513 increased cells' resistance to gefitinib. Our findings suggest that miR-608 and miR-4513 SNPs are independent candidate biomarkers to predict lung adenocarcinoma patients' survival after EGFR-TKIs treatment. These miRNAs and polymorphisms provide clinical potential in patient-tailored treatment decision-making.

BIM deletion polymorphism predicts poor response to EGFR-TKIs in nonsmall cell lung cancer: An updated meta-analysis

BACKGROUND

A germline deletion in BIM (B cell lymphoma-2-like 11) gene has been shown to impair the apoptotic response to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in vitro but its impact on response to EGFR-TKIs in patients of nonsmall cell lung cancer (NSCLC) remains controversial.

METHODS

Eligible literature were searched and screened. Objective response rate (ORR) and disease control rate (DCR) were extracted and aggregated with odds ratio (OR). Hazard ratio (HR) and 95% confidence interval (CI) for progression-free survival (PFS) and overall survival (OS) were extracted and aggregated based on random-effect model.

RESULTS

Fourteen studies including 2694 NSCLC patients were eligible. Individuals harboring BIM deletion polymorphism had inferior ORR (OR = 0.49, 95% CI: 0.34-0.70, P < .001), inferior DCR (OR = 0.50, 95% CI: 0.30-0.84, P = .009). Patients with BIM deletion had shorter OS despite of the heterogeneity between countries (in subgroup of South Korea and Taiwan, HR = 1.34, 95% CI: 1.18-1.53, P < .001; in subgroup of other countries, HR = 2.43, 95% CI: 2.03-2.91, P < .001). The pooled analysis of PFS showed great heterogeneity (I = 79%). All the reported characteristics did not account for the heterogeneity. However, 2 subgroups could be obtained through sensitivity analysis. In one subgroup, patients with BIM deletion polymorphism had shorter PFS (HR = 2.03, 95% CI: 1.71-2.40, P < .001), while in the other subgroup, no significant difference was observed (HR = 0.92, 95% CI: 0.79-1.06, P = .25).

CONCLUSION

NSCLC patients with BIM deletion polymorphism show poor ORR, DCR, and OS after EGFR-TKIs treatment. BIM deletion polymorphism indicates poor response to EGFR-TKIs, and it could be used as a predictor to identify those who would benefit from EGFR-TKIs in NSCLC patients.