Project description:Gene expression profile of lung tumor tissues from EML4-ALK transgenic mouse (generous gift from Prof. H. Mano, Univ. of Tokyo) compared with lung normal tissues
Project description:Oncogenic fusions of EML4 and ALK occur in ~5% of lung adenocarcinomas. EML4- ALK variants have distinct breakpoints within EML4, but the functional differences among these variants remain poorly understood. Here we use CRISPR/Cas9 somatic genome editing to generate autochthonous mouse models of the two most common EML4-ALK variants and show that V3 is more oncogenic than V1. By employing multiplexed genome editing and quantifying the effects of 29 putative tumor suppressor genes on V1- and V3-driven lung cancer growth in vivo we show that many tumor suppressor genes have dramatically variant-specific effects on tumorigenesis. Pharmacogenomic analyses suggest that tumor genotype can also modify responses to therapy. Analysis of a large human EML4-ALK lung cancer cohort identified differences in the genomic landscape depending on the EML4-ALK variant. These findings demonstrate functional heterogeneity between EML4-ALK variants, suggesting that EML4-ALK variants behave more like distinct oncogenes than a uniform entity. More broadly, these findings highlight the dramatic impact of oncogenic fusions partner proteins and coincident tumor suppressor gene alterations on the biology of oncogenic fusion driven cancer.
Project description:Oncogenic fusions of EML4 and ALK occur in ~5% of lung adenocarcinomas. EML4-ALK variants have distinct breakpoints within EML4, but the functional differences among these variants remain poorly understood. Here we use CRISPR/Cas9 somatic genome editing to generate autochthonous mouse models of the two most common EML4-ALK variants and show that V3 is more oncogenic than V1. By employing multiplexed genome editing and quantifying the effects of 29 putative tumor suppressor genes on V1- and V3-driven lung cancer growth in vivo we show that many tumor suppressor genes have dramatically variant-specific effects on tumorigenesis. Pharmacogenomic analyses suggest that tumor genotype can also modify responses to therapy. Analysis of a large human EML4-ALK lung cancer cohort identified differences in the genomic landscape depending on the EML4-ALK variant. These findings demonstrate functional heterogeneity between EML4-ALK variants, suggesting that EML4-ALK variants behave more like distinct oncogenes than a uniform entity. More broadly, these findings highlight the dramatic impact of oncogenic fusions partner proteins and coincident tumor suppressor gene alterations on the biology of oncogenic fusion driven cancer.
Project description:We demonstrate that EML4-ALK siRNAs significantly reduced cell viability in EML4-ALK postive lung cancer cell lines,while overexpression of EML4-ALK increased cell viability in HEK293 cells in vitro. The aim of this study was to analyze the EML4-ALK regulated gene expression in lung cancer.
Project description:Background: Chromosomal inversions involving anaplastic lymphoma kinase (ALK) and echinoderm microtubule associated protein like 4 (EML4) generate a fusion protein EML4-ALK in non-small cell lung cancer (NSCLC). The understanding of EML4-ALK function can be improved by a functional study using normal human cells. Methods: Here we for the first time conduct such study to examine the effects of EML4-ALK on cell proliferation, cellular senescence, DNA damage, gene expression profiles and transformed phenotypes. Results: The lentiviral expression of EML4-ALK in mortal, normal human fibroblasts caused, through its constitutive ALK kinase activity, an early induction of cellular senescence with accumulated DNA damage, upregulation of p16INK4A and p21WAF1, and senescence-associated -galactosidase (SA-β-gal) activity. In contrast, when EML4-ALK was expressed in normal human fibroblasts transduced with telomerase reverse transcriptase (hTERT), which is activated in the vast majority of NSCLC, the cells showed accelerated proliferation and acquired anchorage-independent growth ability in soft-agar medium, without accumulated DNA damage, chromosome aberration, nor p53 mutation. EML4-ALK induced the phosphorylation of STAT3 in both mortal and hTERT-transduced cells, but RNA sequencing analysis suggested that the different signaling pathways contributed to the different phenotypic outcomes in these cells. While EML4-ALK also induced anchorage-independent growth in hTERT-immortalized human bronchial epithelial cells in vitro, the expression of EML4-ALK alone did not cause detectable in vivo tumorigenicity in immunodeficient mice. Conclusions: Our data indicate that the expression of hTERT is critical for EML4-ALK to manifest its in vitro transforming activity in human cells. This study provides the isogenic pairs of human cells with and without EML4-ALK expression.
Project description:Precision oncology has revolutionized the treatment of ALK-positive lung cancer with targeted therapies. However, refractory tumors with compound mutations or diverse resistance mechanisms remain an unmet clinical need. In this study, we established mouse tumor-derived cell models representing the most common EML4-ALK variants in human lung adenocarcinomas and characterized their proteomic profiles. We demonstrated that Eml4-Alk variant 3 confers a worse response to ALK inhibitors, suggesting its role in promoting resistance. In addition, proteomic analysis of brigatinib-treated cells revealed the upregulation of SRC kinase, which is frequently activated in cancer. Co-targeting of ALK and SRC showed remarkable inhibitory effects on both ALK-driven murine tumor growth and ALK-patient-derived cells. This death mechanism is attributed to the profound perturbation of the (phospho)proteomic landscape, together with a synergistic suppressive effect on the mTOR pathway. Taken together, our study identifies the inhibition of ALK and SRC cells and may offer a promising strategy to overcome resistance mechanisms and improve clinical outcomes in ALK-positive lung cancer patients.
Project description:Precision oncology has revolutionized the treatment of ALK-positive lung cancer with targeted therapies. However, refractory tumors with compound mutations or diverse resistance mechanisms remain an unmet clinical need. In this study, we established mouse tumor-derived cell models representing the most common EML4-ALK variants in human lung adenocarcinomas and characterized their proteomic profiles. We demonstrated that Eml4-Alk variant 3 confers a worse response to ALK inhibitors, suggesting its role in promoting resistance. In addition, proteomic analysis of brigatinib-treated cells revealed the upregulation of SRC kinase, which is frequently activated in cancer. Co-targeting of ALK and SRC showed remarkable inhibitory effects on both ALK-driven murine tumor growth and ALK-patient-derived cells. This death mechanism is attributed to the profound perturbation of the (phospho)proteomic landscape, together with a synergistic suppressive effect on the mTOR pathway. Taken together, our study identifies the inhibition of ALK and SRC cells and may offer a promising strategy to overcome resistance mechanisms and improve clinical outcomes in ALK-positive lung cancer patients.
Project description:First line treatment for EML4-ALK fusion-positive lung cancer patient is the use of an ALK tyrosine kinase inhibitor (TKI), such as alectinib. While most patients initially respond to this therapy, many patients often develop relapse, and efficacious therapies for patients with relapse disease are limited. To study EML4-ALK fusion-positive lung cancer, novel murine lung cancer cell lines were generated from C57BL/6 mice using an intratracheally injected Adeno-virus that contains Cas9 and guide RNAs for the EML4-ALK translocation, which leads to the development of lung tumors. Cell lines were derived from these tumors. In an effort to better understand how cells respond to alectinib, we treated EML4-ALK-positive murine cell lines (EA1, EA2, and EA3 cells) in vitro for 1-7 days with either 100nM alectinib or DMSO-control. At each time point, RNA was isolated from each condition. RNA was submitted to RNA-seq. Differential analysis on the RNA-seq data was performed to determine and track gene changes over time between control and treated cells. These data will allow us to better develop novel therapeutics to use in conjunction with alectinib when treating EML4-ALK fusion-positive patients.
Project description:We demonstrate that STAT3 and STAT6 significantly activated after IL4 treatment in EML4-ALK postive lung cancer cell lines The aim of this study was to explore whether IL4 could activate the JAK2-STAT pathway in EML4-ALK-positive cells.
Project description:Cancer-associated fibroblasts (CAFs) are associated with tumor progression and modulate drug sensitivity of cancer cells. However, the underlying mechanisms are often incompletely understood and crosstalk between tumor cells and CAFs can involve soluble secreted as well as adhesion proteins . Interrogating a panel of non-small cell lung cancer (NSCLC) cell lines driven by EML4-ALK fusions we observed substantial CAF-mediated drug resistance to various clinical ALK tyrosine kinase inhibitors (TKIs). Array-based cytokine and kinome profiling of fibroblast-derived conditioned-media identified HGF-MET signaling as a major contributor to CAF-mediated paracrine resistance that can be overcome by MET TKIs. However, ‘Cell Type specific labeling using Amino acid Precursors’ (CTAP)-based expression and phosphoproteomics in direct coculture also highlighted a critical role for the fibronectin-integrin pathway. Flow cytometry analysis confirmed activation of integrin 1 (ITGB1) in lung cancer cells by CAF coculture. Treatment with pharmacological inhibitors, cancer cell-specific silencing or CRISPR-Cas9-mediated knockout of ITGB1 overcame adhesion protein-mediated resistance. Concurrent targeting of MET and integrin signaling effectively abrogated CAF-mediated resistance of EML4-ALK-driven NSCLC cells to ALK TKIs in vitro. Consistently, combination of the ALK TKI, alectinib, with the MET TKI, capmatinib, and/or the integrin inhibitor, cilengitide, was significantly more efficacious than single agent therapy in suppressing tumor growth using an in vivo EML4-ALK-dependent allograft mouse model of NSCLC. In summary, these findings emphasize the complexity of resistance-associated crosstalk between CAFs and cancer cells, which can involve multiple concurrent signaling pathways, and illustrate how comprehensive elucidation of paracrine and juxtacrine resistance mechanisms can lead to more effective therapeutic approaches.