Echinoderm Microtubule-associated Protein-like 4-anaplastic Lymphoma Kinase Research Articles

Successful Treatment with Crizotinib to Overcome Drug Resistance Possibly Due to Mesenchymal-epithelial Transition Amplification in a Lung Cancer Patient with the Echinoderm Microtubule-associated Protein-like 4-anaplastic Lymphoma Kinase Fusion Gene.

Amplification of the mesenchymal-epithelial transition (MET) gene plays an important role in anticancer drug resistance to anaplastic lymphoma kinase-tyrosine kinase inhibitors (ALK-TKIs) in echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK)-rearranged lung cancer cells. We encountered an ALK-rearranged lung cancer patient who developed MET amplification after alectinib treatment and showed an effective response to fifth-line crizotinib. First-line alectinib treatment was effective for 2.5 years; however, liver metastases exacerbated. Liver biopsy specimens revealed MET and human epidermal growth factor receptor 2 (HER2) amplifications. Switching to the MET inhibitor crizotinib improved liver metastases. Crizotinib may be effective in ALK-positive patients with MET amplification.

A Functional Genomics Review of Non-Small-Cell Lung Cancer in Never Smokers.

There is currently a dearth of information regarding lung cancer in never smokers (LCINS). Additionally, there is a difference in somatic mutations, tumour mutational burden, and chromosomal aberrations between smokers and never smokers (NS), insinuating a different disease entity in LCINS. A better understanding of actionable driver alterations prevalent in LCINS and the genomic landscape will contribute to identifying new molecular targets of relevance for NS that will drastically improve outcomes. Differences in treatment outcomes between NS and smokers, as well as sexes, with NSCLC suggest unique tumour characteristics. Epidermal growth factor receptor (EGFR) tyrosine kinase mutations and echinoderm microtubule-associated protein-like 4 anaplastic lymphoma kinase (EML4-ALK) gene rearrangements are more common in NS and have been associated with chemotherapy resistance. Moreover, NS are less likely to benefit from immune mediators including PD-L1. Unravelling the genomic and epigenomic underpinnings of LCINS will aid in the development of not only novel targeted therapies but also more refined approaches. This review encompasses driver genes and pathways involved in the pathogenesis of LCINS and a deeper exploration of the genomic landscape and tumour microenvironment. We highlight the dire need to define the genetic and environmental aspects entailing the development of lung cancer in NS.

Tumor response to radiotherapy and expression of epidermal growth factor receptor mutation and echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase rearrangement in patients with non-small cell lung cancer

BackgroundOne of the main limitations of radiation therapy is the resistance of tumor cells. This study aimed at evaluating the relationship between the expression of epidermal growth factor receptor (EGFR) and echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) and tumor radiosensitivity in patients with non-small cell lung cancer.MethodsMedical case files, pathological results for EGFR and EML4-ALK, and computerized tomography scans of patients with NSCLC treated with thoracic radiation therapy were analyzed.ResultsThe sample size was 101 patients with mean age 58.43 ± 9.89 years. Statistically significant differences were observed in the mean reduction of long tumor diameter during the early treatment phase in EGFR-positive versus EGFR-negative patients (p value = 0.04) and in short tumor diameter during the late treatment phase in EGFR-positive versus EGFR-negative patients (p value = 0.04).ConclusionPatients with overexpression of EGFR mutations are more radiosensitive during the early treatment phase, and EML4-ALK mutations were less radiosensitive regardless of phases.

EML4-ALK fusion gene in non-small cell lung cancer.

Non-small cell lung cancer (NSCLC) is a malignant tumor with a high morbidity and mortality rate that is a threat to human health. With the development of molecular targeted research, breakthroughs have been made on the molecular mechanism of lung cancer. The echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) fusion gene is one of the most important pathogenic driver genes of NSCLC discovered thus far. Four generations of targeted drugs for EML4-ALK have been developed, with patients benefiting significantly from these drugs. Therefore, EML4-ALK has become a research hotspot in NSCLC. The aim of the present study is to introduce the current research progress of EML4-ALK and its association with NSCLC.

Gastric mesenchymal tumor with smooth muscle differentiation and echinoderm microtubule‐associated protein‐like 4‐anaplastic lymphoma kinase (EML4‐ALK) fusion

Gastric mesenchymal tumors are relatively rare, and their molecular pathogeneses are poorly understood, except for gastrointestinal stromal tumor, desmoid, and inflammatory myofibroblastic tumors. We report a case of a gastric mesenchymal tumor with prominent smooth muscle cell differentiation and an echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) fusion. On gross section, the tumor was 26 mm at the largest diameter, well-circumscribed, and located in the submucosal and muscular layers of the stomach wall. Histologically, the tumor comprised intersecting fascicles of spindle cells, non-atypical nuclei, and highly eosinophilic cytoplasm. Myxoid changes were observed focally, but inflammatory infiltrates were only evident in limited areas. Immunochemical staining revealed that the tumor was positive for α-smooth muscle actin and desmin. Diffuse positive staining for h-caldesmon was observed throughout the tumor, which suggested smooth muscle cell differentiation. Intracytoplasmic staining for ALK protein was also observed, and fluorescence in situ hybridization using ALK break-apart probes showed split chromosomal signals. RNA-sequencing analysis identified EML4-ALK fusion transcripts. We concluded that the tumor was a gastric mesenchymal tumor with smooth muscle differentiation based on its distinct differential smooth muscle properties, such as highly eosinophilic cytoplasm and diffuse expression of h-caldesmon. Furthermore, activated ALK may underly the tumor's pathogenesis.

EML4-ALK-mediated activation of the JAK2-STAT pathway is critical for non-small cell lung cancer transformation

BackgroundThe echinoderm microtubule-associated protein-like-4 anaplastic lymphoma kinase (EML4-ALK) fusion gene was identified in a subset of non-small cell lung cancer (NSCLC) patients. They responded positively to ALK inhibitors. This study aimed to characterize the mechanisms triggered by EML4-ALK to induce NSCLC transformation.MethodsHEK293 and NIH3T3 cells were transfected with EML4-ALK variant 3 or pcDNA3.1-NC. H2228 cells were transfected with siRNA-EML4-ALK or siRNA-NC. Cell viability and proliferation were measured by the CCK-8 and EdU methods, respectively. Flow cytometry revealed apoptosis. Gene expression profiles were generated from a signaling pathway screen in EML4-ALK-regulated lung cancer cells and verified by qPCR and Western blotting. The co-immunoprecipitation and immunohistochemistry/ immunofluorescence determined the interaction and colocalization of JAK2-STAT pathway components with EML4-ALK.ResultsMicroarray identified several genes involved in the JAK2-STAT pathway. JAK2 and STAT6 were constitutively phosphorylated in H2228 cells. EML4-ALK silencing downregulated phosphorylation of STAT6. Expression of EML4-ALK in HEK293 and NIH3T3 cells activated JAK2, STAT1, STAT3, STAT5, and STAT6. In EML4-ALK-transfected HEK293 cells and EML4-ALK-positive H2228 cells, activated STAT6 and JAK2 colocalized with ALK. STAT3 and STAT6 were phosphorylated and translocated to the nucleus of H2228 cells following IL4 or IL6 treatment. Apoptosis increased, while cell proliferation and DNA replication decreased in H2228 cells following EML4-ALK knockdown. In contrast, HEK293 cell viability increased following EML4-ALK overexpression, while H2228 cell viability significantly decreased after treatment with ALK or JAK-STAT pathway inhibitors.ConclusionsOur data suggest that the aberrant expression of EML4-ALK leads to JAK2-STAT signaling pathway activation, which is essential for the development of non-small cell lung cancer.

Druggable driver gene alterations in redefined large cell carcinoma in Chinese patients: an observational study.

BackgroundFew reports have investigated the genetic status of large cell carcinoma (LCC) in Chinese patients under the 2015 World Health Organization (WHO) classification. We aimed to analyze the distribution of druggable driver gene alterations, including mutations in epidermal growth factor receptor (EGFR), Kirsten rat sarcoma 2 viral oncogene homolog (KRAS), proto-oncogene B-Raf (BRAF), and phosphatidylinositol-4,5 biphosphate 3-kinase catalytic subunit alpha (PIK3CA) and translocations in echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) and ROS proto-oncogene 1 (ROS1), in a large population of patients with LCC under the 2015 WHO classification, and to assess the clinical outcomes of patients with LCC harboring these genetic alterations.MethodsA cohort of 322 patients with LCC resected between June 2015 and December 2018 was included in this study. The clinical characteristics of the patients and data on the distribution of EGFR, KRAS, BRAF, PIK3CA, EML4-ALK, and ROS1 alterations were retrospectively collected. The disease-free survival (DFS) of patients with LCC was analyzed using the log-rank test.ResultsAmong the patients with redefined LCC, the proportion of males was much higher than that of females. Detection of LCC was more frequent in patients >60 years of age (71.4%). Mutations of EGFR were found in 3.6% of the LCC participants, predominantly in non-smokers. Mutations in KRAS were observed in 7.8% of the LCC patients, mainly in males and smokers. Mutations in PIK3CA and EML4-ALK translocations comprised 2.1% and 0.52% of the identified alterations, respectively. No alterations were identified in ROS1 and BRAF. After molecular stratification, no significant difference in DFS was identified between wild-type (WT) and mutation groups (29.91±3.83 vs. 25.33±6.04 months, P=0.48).ConclusionsUnder the 2015 WHO criteria, LCC was more frequently detected in elderly male patients with inferior prognoses. The frequency of EGFR and KRAS mutations was found to be the highest. Mutations in EGFR occurred more frequently in non-smokers, whereas KRAS mutations occurred predominantly in males and smokers. The PIK3CA mutations and EML4-ALK translocations were rare in patients with LCC. Our data revealed that the identification of clinically actionable molecular alterations in LCC may help guide personalized cancer treatment decisions in the future.

Advances in Drug Resistance Mechanisms and Prognostic Markers of Targeted Therapy in ALK-positive Non-small Cell Lung Cancer

棘皮动物微管相关类蛋白4-间变性淋巴瘤激酶(echinoderm microtubule-associated protein like 4-anaplastic lymphoma kinase, EML4-ALK)融合占非小细胞肺癌(non-small cell lung cancer, NSCLC)患者的3%-5%。随着对该驱动基因的深入研究，以Crizotinib为代表的ALK抑制剂逐渐被开发并应用于临床。然而，不同患者对ALK靶向治疗的反应存在差异，且多数ALK靶向治疗患者最终会不可避免地出现耐药，导致肿瘤进展。利用预后标志物监测患者疗效及时改变治疗方案，以及根据耐药机制选择个体化的后续治疗，可以有效地改善患者的预后。本文将对ALK抑制剂的耐药机制以及相关的预后标志物展开综述，探讨ALK靶向治疗疗效预测以及耐药患者后续治疗方案的选择。

Identification of novel bioactive molecules from garlic bulbs: A special effort to determine the anticancer potential against lung cancer with targeted drugs.

Garlic (Allium sativum L.), is a predominant spice, which is used as an herbal medicine and flavoring agent, since ancient times. It has a rich source of various secondary metabolites such as flavonoids, terpenoids and alkaloids, which have various pharmacological properties. Garlic is used in the treatment of various ailments such as cancer, diabetes and cardiovascular diseases. The present study aims to explore the plausible mechanisms of the selected phytocompounds as potential inhibitors against the known drug targets of non-small-cell lung cancer (NSCLC). The phytocompounds of garlic were identified by gas chromatography-mass spectrometry (GC–MS) technique. Subsequently, the identified phytocompounds were subjected to molecular docking to predict the binding with the drug targets, epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2 (HER2), echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) and group IIa secretory phospholipase A2 (sPLA2-IIA). Molecular dynamics is used to predict the stability of the identified phytocompounds against NSCLC drug targets by refining the intermolecular interactions formed between them. Among the 12 phytocompounds of garlic, three compounds[1,4-dimethyl-7-(1-methylethyl)-2-azulenyl]phenylmethanone, 2,4-bis(1-phenylethyl)-phenol and 4,5–2 h-oxazole-5-one,4-[3,5-di-t-butyl-4-methoxyphenyl] methylene-2-phenyl were identified as potential inhibitors, which might be suitable for targeting the different clinical forms of EGFR and dual inhibition of the studied drug targets to combat NSCLC. The result of this study suggest that these identified phytocompounds from garlic would serve as promising leads for the development of lead molecules to design new multi-targeting drugs to address the different clinical forms of NSCLC.

Distribution of EML4-ALK fusion variants and clinical outcomes in patients with resected non-small cell lung cancer

ObjectivesThe molecular profiles and prognosis of anaplastic lymphoma kinase (ALK) fusion and resectable non-small cell lung cancer (NSCLC) remain unclear. This study aimed to explore the distribution of ALK fusion variants and prognostic factors in patients with surgically resected NSCLC. Material and methodsAmong the 93 ALK positive surgical patients screened by immunohistochemistry (IHC) or real-time polymerase chain reaction (RT-PCR), 63 patients were confirmed as ALK rearrangement by next-generation sequencing (NGS), including 55 cases of stage I-III and 8 cases of stage IV. Medical records were retrospectively reviewed, the distribution of ALK fusion variants and prognostic factors were analyzed. ResultsAll of the 55 early stage patients were histological adenocarcinoma. No other fusion types were found except for echinoderm microtubule-associated protein-like 4- anaplastic lymphoma kinase (EML4-ALK). EML4-ALK variant 1 (E13:A20; 25/55, 45.5 %) was the predominant variant type, followed by EML4-ALK variant 3 (E6:A20; 19/55, 34.5 %) and variant 2 (E20:A20; 8/55, 14.5 %). Concomitant mutations occurred in 22 patients (22/55, 40.0 %), which involved in 32 co-mutations from 12 kinds of mutated genes. TP53 mutations were most common in coexisting mutations (13/32, 40.6 %). TP53 mutations were less frequently occurred in variant 1 group (3/25, 12.0 %) than in non-variant 1 group (10/30, 33.3 %, P = 0.064). The median disease-free survival (DFS) of the 55 patients was 22.1 months, and the median overall survival (OS) was not mature at the time of analysis. Multivariable analysis showed that stage T3 and EML4-ALK variant 3 were independent prognostic factors for shorter DFS. Neither TP53 mutations nor any coexisting mutations were related to prognosis. ConclusionsThis study illustrated the patterns of EML4-ALK fusion variants and gene profiles in patients with resected NSCLC. Advanced T stage and EML4-ALK variant 3 were associated with worse prognosis. The role of TP53 mutations in prognosis is worthy of further study.

Screening of significant oncogenic changes in air pollution-related lung cancer in Chinese population.

BackgroundAir pollution-related lung cancer has been considered as a deteriorating public health problem worldwide, particularly in developing countries. The highly air polluted regions in China particularly Xuanwei and Fuyuan counties have markedly high lung cancer rates and are considered as good models to study air pollution-related lung cancer. The present study investigated the clinically significant oncogenes in air pollution-related lung cancers.MethodsA combination of reverse transcriptase PCR (RT-PCR) and DNA sequencing was applied to examine the expression, mutations, or fusions of target genes, including human epidermal growth factor receptor 2 (HER2), echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK), and cluster of differentiation 74-ROS proto-oncogene 1 (CD74-ROS1).ResultsOf the 82 patients with lung cancer, 20.7% (17/82) exhibited HER2 up-regulation, and 1.2% (1/82) harbored HER2 insertion at exon 20. HER2 overexpression was not associated with air pollution levels and smoking status. A total of 6.1% (5/82) samples exhibited ALK gene rearrangements; two belonged to EML4-E2 + ALK-E20 and three were EML4-E13 + ALK-E20; all the five cases occurred either in smokers or in patients from the most air-polluted region. A total of 3.6% (3/82) carried the CD74-ROS1 fusion gene (CD74-E6 + ROS1-E34); the fusion event was not statistically associated with air pollution levels.ConclusionsThe high rates of prevalence indicated in the present study suggest that the screening of HER2 overexpression and EML4-ALK fusion events may assist in guiding treatment in air pollution-related lung cancer; the RT-PCR-based test proposed in this study may be a useful tool in clinical applications to screen these genetic changes.

Identification of anaplastic lymphoma kinase fusions in clear cell renal cell carcinoma.

As one of the most common types of renal cancer, clear cell renal cell carcinoma (ccRCC) in advanced stages constitutes a continued major challenge for uro-oncologists, as the identification of novel driver mutations and the development of novel targeted therapies against them remain an unmet need. Aberrations in anaplastic lymphoma kinase (ALK), a rational therapeutic target, as verified in lung cancer with ALK rearrangement, have been implicated in the pathogenesis of multiple human cancers. In the present study, we screened ALK expression in 87 pathologically defined ccRCCs via immunohistochemistry (IHC) using a newly developed rabbit anti-human ALK monoclonal antibody (clone D5F3). Four patients tested positive for ALK expression, as confirmed by IHC. Among them, 2 patients were further confirmed with fluorescence in situ hybridization (FISH) assay with the use of the Vysis LSI ALK dual color break-apart probe. Furthermore, we detected the existence of the echinoderm microtubule-associated protein-like 4/anaplastic lymphoma kinase (EML4-ALK) (E13:A20, variant 1) fusion gene in tumors from these two patients by using rapid amplification of cDNA ends (RACE)-coupled PCR sequencing and RT-PCR. Notably, we first showed that enforced EML4-ALK expression could significantly promote in vitro proliferation, clonogenic colony formation and apoptosis resistance in HK2 immortalized normal renal tubal epithelial cells and their in vivo outgrowth when injected into immunocompromised nude mice. Importantly, this pro-tumorigenic effect was completely abolished by the ALK-specific inhibitor crizotinib, indicating the potential effectiveness of ALK-specific inhibitors in treating ALK-rearranged ccRCC patients. Our data revealed that ALK fusions exist in adult ccRCC, providing a rationale for ALK inhibitor therapy in selected patients with ccRCC.

Clinicopathological and Prognostic Significance of EML4-ALK Rearrangement in Patients with Surgically Resected Lung Adenocarcinoma: A Propensity Score Matching Study.

ObjectiveThe echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) fusion gene is a key oncogenic driver in non-small cell lung cancer (NSCLC). This study analyzed the clinicopathological characteristics and prognostic significance of EML4-ALK fusion gene in patients with surgically resected adenocarcinoma.MethodsThe clinicopathological characteristics of 1056 consecutive patients with surgically resected stage I–IIIA adenocarcinoma were collected from February 2014 to October 2014, and EML4-ALK rearrangement was detected using real-time polymerase chain reaction (RT-PCR) technology. To compare the imaging and pathological features, a propensity score matching (PSM) method was performed. The follow-up information was collected to evaluate the long-term outcomes of patients with EML4-ALK rearrangement.ResultsThe prevalence of EML4-ALK rearrangement was 6.6% in 1056 consecutive patients. A total of 70 EML4-ALK-positive and 210 EML4-ALK-negative patients were identified after PSM. Imaging and pathological analyses showed that EML4-ALK rearrangement was significantly associated with less ground-glass opacity (GGO) (adjusted OR=1.38, 95% CI=1.03–1.85, Ptrend=0.029) and higher prevalence of non-invasive mucinous adenocarcinoma mucin-laden adenocarcinomas (non-IMA MLA, adjusted OR=6.79, 95% CI=2.69–17.17, P<0.001). EML4-ALK rearrangement was found to be an unfavorable prognostic factor for disease-free survival (DFS) in female patients (HR=2.26, 95% CI=1.13–4.53, P=0.021).ConclusionOur results suggest that adenocarcinomas harboring EML4-ALK fusion gene exhibit specific radiological and pathological characteristics compared with EML4-ALK-negative adenocarcinomas. In female patients, EML4-ALK rearrangement was associated with shorter DFS.

Elevated levels of pre-treatment lactate dehydrogenase are an unfavorable predictor factor in patients with EML4-ALK rearrangement non-small cell lung cancer treated with crizotinib.

BackgroundTargeted therapy is an important treatment for advanced non-small cell lung cancer (NSCLC) patients with specific genetic mutations, crizotinib can prolong survival in advanced NSCLC patients with echinoderm microtubule-associated protein-like 4–anaplastic lymphoma kinase (EML4-ALK) rearrangement. We performed a retrospective analysis to investigate the association between the lactate dehydrogenase (LDH) levels and progression-free survival (PFS) in patients with EML4-ALK rearrangement NSCLC receiving treatment with crizotinib.MethodsAdvanced (stage IIIb–IV) NSCLC patients with EML4-ALK rearrangement receiving treatment with crizotinib were enrolled between January 2007 and January 2016 at Peking Union Medical College and Cancer Hospital Chinese Academy of Medical Sciences.ResultsOverall, 212 patients were enrolled. Kaplan–Meier univariate analysis showed that elevated pre-treatment LDH level (7.9 vs 14.1 months, HR =1.251, CI: 1.008–1.553, P=0.004) was significantly associated with shorter PFS, while the post-treatment mean-LDH level (13.3 vs 14.3 months, HR=1.439, 95% CI: 0.994–2.082, P=0.970) was not significantly associated with PFS. Cox proportional hazards model also identified that pre-treatment LDH level (HR=2.085, 95% CI: 1.150–3.781, P=0.016) was associated with the PFS. Logistic regression analysis showed that post-treatment LDH level was associated with creatine kinase (OR=6.712, 95% CI 3.395–13.273, P<0.01), creatine kinase isoenzyme (OR=6.297, 95% CI 2.953–13.427, P<0.01), and hemoglobin (OR=4.163, 1.741–9.956, P<0.001).ConclusionAn elevated pre-treatment serum LDH level (>250 U/L) was significantly associated with shorter PFS in patients with EML4-ALK rearrangement NSCLC. Post-treatment elevated serum LDH level was not significantly associated with PFS, which related to adverse events including muscle damage and anemia.

Association of PFS with levels of pretreatment lactate dehydrogenase in patients with EML4-ALK rearrangement non-small cell lung cancer treated with ALK tyrosine kinase inhibitor.

e20513 Background: We performed a retrospective analysis to investigate the association between the lactate dehydrogenase (LDH) levels and progression-free survival (PFS) in patients with echinoderm microtubule-associated protein-like 4-anaplasticlymphoma kinase (EML4-ALK) rearrangement non-small cell lung cancer (NSCLC) receiving treatment with crizotinib. Methods: Advanced NSCLC patients with EML4-ALK rearrangement receiving treatment with crizotinib were enrolled at Peking Union Medical College and Cancer Hospital Chinese Academy of Medical Sciences between January 2007 and January 2016. Pre-treatment or post-treatment serum LDH levels were analyzed with progression-free survival (PFS) and patients’ clinical parameters. Results: Overall, 212 patients were studied. Kaplan-Meier univariate analysis showed that elevated pre-treatment LDH level (7.9 vs. 14.1 months, P = 0.004) were associated with PFS, while the mean value of post-treatment LDH level (14.3 vs. 13.3 months, P = 0.970) were not associated with PFS. Coxproportional hazards model also identified that pre-treatment LDH level (hazard ratio [HR] = 1.841, 95% confidence interval [CI] 1.062-3.190, P = 0.030) was associated with the PFS. Logistic regression analysis showed that post-treatment LDH level was associated with creatine kinase(OR = 6.712, 95% CI 3.395-13.273, P &lt; 0.01), CKMB (OR = 6.297, 95% CI 2.953-13.427, P &lt; 0.01), and hemoglobin(OR = 4.163, 1.741-9.956, P = 0.001). Conclusions: An elevated pre-treatment serum LDH level ( &gt; 250U/L) is significantly associated with shorter PFS in patients with EML4-ALK rearrangement NSCLC. Post-treatment elevated serum LDH level is associated with multiple factors including muscle damage and anemia, rather than PFS.

What are the Uncommon Anaplastic Lymphoma Kinase (ALK) Fusions in Non-Small Cell Lung Cancer?

Lung cancer carcinogenesis is increasingly related to genetic disorders that lead to the use of specific targeted therapies which improve clinical outcome and survival. Gene fusion is one of the mechanisms of lung cancer pathogenesis besides gene mutation. The oncogenic echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) fusion gene was the first described in non-small cell lung cancer (NSCLC) and it’s the most frequent ALK rearrangement which occurs in approximately 5% of NSCLC. The development of sequencing technology has allowed the discovery of other ALK partners that cause an ALK fusion in NSCLC. They are still less known, however. The aim of this review is to report the novel ALK fusions in NSCLC described in the literature and their particular characteristics. We will present the kinesin family member 5B (KIF5B) - ALK fusion, the huntingtin interacting protein 1 (HIP 1)- ALK fusion, and other uncommon ALK fusions.

Apatinib reverses alectinib resistance by targeting vascular endothelial growth factor receptor 2 and attenuating the oncogenic signaling pathway in echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase fusion gene-positive lung cancer cell lines.

Overexpression of insulin growth factor 1 receptor (IGF-1R) and its ligand, insulin growth factor 1 (IGF-1), is related to treatment resistance and worse prognosis in many types of tumors. We reported recently that IGF-1R activation by IGF induces resistance to alectinib and stimulates the production of vascular endothelial growth factor, which indicates that IGF induces alectinib resistance and angiogenesis. This study aimed to determine the effect of bigeminal inhibition of anaplastic lymphoma kinase (ALK) and angiogenesis on human insulin growth factor 1 receptor (hIGF-1)-triggered drug resistance in echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK)-positive lung cancer. Human lung adenocarcinoma H3122 and H2228 cells were exposed to a combination of insulin growth factor 1 receptor (IGF-1), alectinib, or apatinib. The effects of the combination therapy were examined using cell the Cell Counting Kit-8 assay, the colony-forming assay, the scratch test, and flow cytometry analysis, and the molecular mechanism was assessed by western blot. At nontoxic concentrations, apatinib restored alectinib sensitivity by increasing drug-induced apoptosis and inhibiting viability, migration, and invasion in IGF-triggered drug resistant cells. Moreover, we found that apatinib restored sensitivity to alectinib mainly through suppression of the ALK downstream signaling pathway and antiangiogenesis signaling. Taken together, our results indicate that simultaneous inhibition of ALK and vascular endothelial growth factor R2 by the combination of alectinib with apatinib may be useful for controlling progression of EML4-ALK fusion gene lung cancer by reversing ALK-TKI resistance and inhibiting angiogenesis.

Protocol to Improve Genotyping of Non-Small-Cell Lung Cancer Diagnosed Using EBUS-TBNA.

Targeted therapies for non-small-cell lung cancers (NSCLCs) are based on the presence of driver mutations such as epidermal growth factor receptor (EGFR) and the echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) translocation. Endobronchial ultrasound-guided-transbronchial needle aspiration (EBUS-TBNA) is a first-line modality for diagnosing and staging NSCLC. A quality improvement protocol maximizing tissue acquisition for molecular analysis has not been previously described. We instituted a standardized protocol designed from a multidisciplinary meeting of the pulmonology, oncology, and pathology departments for the acquisition and on-site processing of samples obtained through EBUS-TBNA to improve the yield for genetic analysis of EGFR and ALK testing. Preprotocol there were 50 NSCLCs (29 adenocarcinomas) and postprotocol there were 109 NSCLCs (52 adenocarcinomas). A statistically significant increase in yield for molecular analysis was seen in both EGFR (36% preprotocol and 80% postprotocol, P < 0.01) and ALK (41% preprotocol and 80% postprotocol, P < 0.01). There was no difference in complications preprotocol and postprotocol. Implementation of a standardized protocol with EBUS-TBNA was associated with an increase in adequacy for molecular genetic analysis in NSCLC.

LincROR influences the stemness and crizotinib resistance in EML-ALK+ non-small-cell lung cancer cells.

IntroductionEchinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4–ALK) is identified as an important pathogenic factor in patients with non-small-cell lung cancer (NSCLC) and could induce a stem-like phenotype in NSCLC cells. Crizotinib is commonly used for EML4–ALK+ NSCLC treatment, but its acquired resistance results in tumor recurrence. Long intergenic noncoding RNA, regulator of reprogramming (lincROR) is related to the acquisition and maintenance of self-renewal and stemness features of cancer stem cells. It has been documented that lincROR is implicated in chemoresistance. However, the correlations of lincROR and EML4–ALK in stem cell-like properties and of lincROR and crizotinib resistance in NSCLC cells are yet to be elucidated.Patients and methodsIn the present study, we investigated the expression profile of lincROR in EML–ALK NSCLC tissues, and the potential role of lincROR in prognosis was then analyzed. Subsequently, its association with stem cell-like properties of EML–ALK+ NSCLC cells was determined. Furthermore, the correlation of lincROR with crizotinib and the effects of lincROR and crizotinib on cell viability of EML4–ALK+ NSCLC cells were all explored.ResultsThe results showed that lincROR expression was upregulated in EML4–ALK+ NSCLC tissues relative to EML4–ALK− NSCLC tissues. Low-expressed lincROR was related to a favorable prognosis of patients with EML–ALK NSCLC. lincROR overexpression could enhance the stemness features of EML–ALK+ NSCLC cells which were repressed by ALK knockdown.ConclusionWe found that lincROR expression was significantly inhibited because of the increased concentration of crizotinib in EML4–ALK+ NSCLC cells. Furthermore, lincROR overexpression increased cell viability of EML4–ALK+ NSCLC cells, which was impaired by crizotinib. Conjointly, these results suggested the important role of lincROR in EML–ALK+ NSCLC. lincROR may serve as a potential therapeutic target to overcome chemotherapy resistance in EML–ALK+ NSCLC.

Management of Resistance to First-Line Anaplastic Lymphoma Kinase Tyrosine Kinase Inhibitor Therapy.

A decade after the discovery of echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase (EML4-ALK) rearrangements in non-small cell lung cancer (NSCLC), several inhibitors have gained regulatory approval, and their sequential use has deferred platinum-based chemotherapy to later lines of therapy. Nevertheless, although most ALK-driven tumors dramatically respond to ALK TKIs , all patients ultimately develop drug-resistant disease. Analysis of post-progression biopsy samples has provided invaluable insight into the mechanisms of resistance, now informing on subsequent therapeutic strategies. In particular, the identification of secondary ALK mutations, which are a common mechanism of resistance to both first-generation and to an even larger extent to second-generation ALK TKIs, may shape a personalized optimal treatment strategy beyond the current first-line choice. Alectinib has now become a preferred treatment option in the first line of therapy, and extrapolation of data obtained from post-progression samples after second-line next-generation ALK TKIs suggests that acquired resistance is likely to be mediated in more than half of patients by ALK resistance mutations. Nevertheless, clinical and preclinical evidence suggests that multiple resistance mechanisms may co-exist at different levels in the same TKI-resistant patient. Newer ALK tyrosine kinase inhibitors (TKIs) overcome some resistance mutations through higher exposure and potency, and generally present greater CNS activity, but are unlikely to overcome resistance mediated through separate oncogenic pathway activations, or epithelial to mesenchymal transition (EMT) and small cell lung cancer (SCLC) transformation. Furthermore, while resistance mutations can be detected through commonly available sequencing methods, the identification of other mechanisms of resistance is much less straightforward in the clinic. We hypothesize that the ALK resistance mutation status will likely be crucially important in the choice of second-line therapy after a second-generation TKI. Emerging clinical data also refines the optimal placing of PD-1- and PD-L1-directed immunotherapy in the treatment sequence.