ABSTRACT: We performed RNA-seq using 19 human surgically-resected lung adenocarcinomas to investigate of difference between EGFR-mutated and wild-type lung adenocarcinomas.
Project description:PURPOSE: Although epidermal growth factor receptor (EGFR) mutated adenocarcinomas initially have very high response rates to EGFR tyrosine kinase inhibitors (TKIs), most atients eventually develop resistance. Patient derived xenografts (PDXs) are considered preferred preclinical models to study the biology of patient tumors. EGFR-mutant PDX models may be valuable tools to study the biology of these tumors and to elucidate mechanisms of resistance to EGFR-targeted therapies. METHODS: Surgically resected early stage non-small cell lung carcinoma (NSCLC) tumors were implanted into non-obese diabetic severe combined immune deficient (NODSCID) mice. EGFR TKI treatment was initiated at tumor volumes of 150 mm3. Gene expression analysis was performed using microarray platform. RESULTS: Of 33 lung adenocarcinomas with EGFR activating mutations, only 6 engrafted 18%) and could be propagated beyond passage one. Engraftment was associated with upregulation of genes involved in mitotic checkpoint and cell proliferation. A differentially expressed gene set between engrafting and non-engrafting patients could identify EGFRmutant patients with significantly different prognoses in The Cancer Genome Atlas (TCGA) Lung Adenocarcinoma datasets. The PDXs included models with variable sensitivity to first- and second-generation EGFR TKIs and the monoclonal antibody cetuximab. All EGFR-mutant NSCLC PDXs studied closely recapitulated their corresponding patient tumor phenotype and clinical course, including response pattern to EGFR TKIs. CONCLUSIONS: PDX models closely recapitulate primary tumor biology and clinical outcome. They may serve as important laboratory models to investigate mechanisms of resistance to targeted therapies, and for preclinical testing of novel treatment strategies.
Project description:To study heterogenous cellular function and behaviors, we isolated individual cells from freshly resected and dissociated two human primary lung adenocarcinomas, removed DAPI-positive dead cells, and performed single cell analysis using the 10x Genomics Chromium platform.
Project description:Identification of genes up-regulated in ALK-positive and EGFR/KRAS/ALK-negative lung adenocarcinomas. To elucidate molecular characteristics of lung adenocarcinomas (ADCs) with ALK mutations and those without EGFR, KRAS and ALK mutations, 226 primary lung ADCs of pathological stage I-II, examined for the status of EGFR, KRAS and ALK mutations, were subjected to genome-wide expression profiling, and genes up-regulated in lung ADCs with ALK mutations and those without EGFR, KRAS and ALK mutations were identified. One hundred and seventy-four genes, including ALK, were selected as being up-regulated specifically in 79 lung ADCs without EGFR and KRAS mutations. These 79 cases were divided into: 11 cases of ALK-positive ADCs, 36 cases of group A triple-negative ADCs, and 32 cases of group B triple-negative ADCs, by unsupervised clustering according to the expression of the 174 genes. In ALK-positive ADCs, 30 genes, including ALK itself and GRIN2A, were significantly overexpressed. Group A triple-negative ADC cases showed significantly worse prognoses for relapse and death than ADC cases with EGFR, KRAS or ALK mutations and group B triple-negative ADC cases. Nine genes were identified as being significantly up-regulated in group A triple-negative ADC cases and critical for predicting their prognosis. The nine genes included DEPDC1, which had been identified as a candidate diagnostic and therapeutic target in bladder and breast cancers. Genes discriminating this group of ADCs will be useful for selection of patients who will benefit from adjuvant chemotherapy after surgical resection of stage I-II triple-negative ADCs and also informative for the development of molecular targeting therapies for these patients. Expression profiles in of 226 lung adenocarcinomas (127 with EGFR mutation, 20 with KRAS mutation, 11 with EML4-ALK fusion and 68 triple negative cases).
Project description:Identification of genes up-regulated in ALK-positive and EGFR/KRAS/ALK-negative lung adenocarcinomas. To elucidate molecular characteristics of lung adenocarcinomas (ADCs) with ALK mutations and those without EGFR, KRAS and ALK mutations, 226 primary lung ADCs of pathological stage I-II, examined for the status of EGFR, KRAS and ALK mutations, were subjected to genome-wide expression profiling, and genes up-regulated in lung ADCs with ALK mutations and those without EGFR, KRAS and ALK mutations were identified. One hundred and seventy-four genes, including ALK, were selected as being up-regulated specifically in 79 lung ADCs without EGFR and KRAS mutations. These 79 cases were divided into: 11 cases of ALK-positive ADCs, 36 cases of group A triple-negative ADCs, and 32 cases of group B triple-negative ADCs, by unsupervised clustering according to the expression of the 174 genes. In ALK-positive ADCs, 30 genes, including ALK itself and GRIN2A, were significantly overexpressed. Group A triple-negative ADC cases showed significantly worse prognoses for relapse and death than ADC cases with EGFR, KRAS or ALK mutations and group B triple-negative ADC cases. Nine genes were identified as being significantly up-regulated in group A triple-negative ADC cases and critical for predicting their prognosis. The nine genes included DEPDC1, which had been identified as a candidate diagnostic and therapeutic target in bladder and breast cancers. Genes discriminating this group of ADCs will be useful for selection of patients who will benefit from adjuvant chemotherapy after surgical resection of stage I-II triple-negative ADCs and also informative for the development of molecular targeting therapies for these patients.