Project description:DNA CpG methylation profiling of LC patients samples were performed to understand genotype to phenotype corrlelations , novel molecular subtypes and cell of origins Lung carcinoids (LCs) are rare and slow growing primary lung neoplasms that are understudied. Here, we performed targeted exome sequencing using a 354-cancer gene panel (n=29), mRNA sequencing (n=30) and DNA methylation assay (n=18) on macro-dissected lung carcinoids. The mutations we identified were enriched for genes involved in covalent histone modification/chromatin remodeling (34.5%) (MEN1, ARID1A, KMT2C and KMT2A were recurrently mutated) as well as DNA repair (17.2%) pathways. Unsupervised clustering and principle component analysis on gene expression and DNA methylation profiles showed 3 robust molecular subtypes (LC1, LC2, LC3) with distinct clinical features. MEN1 gene mutations were found to be enriched and exclusively in the LC2 subtype (p-value<0.001). The LC3 subtype is predominately found at endobronchial lung and earlier age of diagnosis. Immunohistochemical staining of two biomarkers, ASCL1 and S100, is sufficient to stratify the three subtypes. This molecular classification of lung carcinoids into three subtypes may help improve treatment decision and clinical management.
Project description:Lung carcinoids (LCs) are rare and slow growing primary lung neoplasms that are understudied. Here, we performed targeted exome sequencing using a 354-cancer gene panel (n=29), mRNA sequencing (n=30) and DNA methylation assay (n=18) on macro-dissected lung carcinoids. The mutations we identified were enriched for genes involved in covalent histone modification/chromatin remodeling (34.5%) (MEN1, ARID1A, KMT2C and KMT2A were recurrently mutated) as well as DNA repair (17.2%) pathways. Unsupervised clustering and principle component analysis on gene expression and DNA methylation profiles showed 3 robust molecular subtypes (LC1, LC2, LC3) with distinct clinical features. MEN1 gene mutations were found to be enriched and exclusively in the LC2 subtype (p-value<0.001). The LC3 subtype is predominately found at endobronchial lung and earlier age of diagnosis. Immunohistochemical staining of two biomarkers, ASCL1 and S100, is sufficient to stratify the three subtypes. This molecular classification of lung carcinoids into three subtypes may help improve treatment decision and clinical management.
Project description:Although there has been increased knowledge about the molecular biology of neuroendocrine tumors (NETs), little is known about thymic carcinoids and even less about those with excessive hormone disorders, such as ectopic ACTH syndrome. This study was designed to gain insights into molecular networks underlying the tumorigenesis of thymic carcinoids with ACTH secretion. By an approach integrating cDNA microarray and methods of computational biology, we compare gene expression profile between ACTH-producing thymic carcinoids and normal thymus. Totally there are 63 biological categories increased and 108 decreased in thymic carcinoids. Cell proliferation was stimulated which may explain the relatively uncontrolled cell growth of the tumor. Dysregulation of Notch signaling pathway was likely underlying the neuroendocrine features of this type of tumors. Moreover, the inhibition of the immunity and the increased neuropeptide signaling molecules, POMC and its sorting molecule CPE, made the clinical manifestation reasonable and thus validated the array data. In conclusion, thymic carcinoids have distinguished gene expression pattern from the normal thymus and they are characterized by deregulations of a series of biofunctions, which may be involved in the development of neuroendocrine tumor. This study hence has provided not only a detailed comprehension of the molecular pathogenesis of thymic carcinoid with ectopic ACTH syndrome, but also a road map to approach thymic neuroendocrine tumors at the system level.
Project description:Although there has been increased knowledge about the molecular biology of neuroendocrine tumors (NETs), little is known about thymic carcinoids and even less about those with excessive hormone disorders, such as ectopic ACTH syndrome. This study was designed to gain insights into molecular networks underlying the tumorigenesis of thymic carcinoids with ACTH secretion. By an approach integrating cDNA microarray and methods of computational biology, we compare gene expression profile between ACTH-producing thymic carcinoids and normal thymus. Totally there are 63 biological categories increased and 108 decreased in thymic carcinoids. Cell proliferation was stimulated which may explain the relatively uncontrolled cell growth of the tumor. Dysregulation of Notch signaling pathway was likely underlying the neuroendocrine features of this type of tumors. Moreover, the inhibition of the immunity and the increased neuropeptide signaling molecules, POMC and its sorting molecule CPE, made the clinical manifestation reasonable and thus validated the array data. In conclusion, thymic carcinoids have distinguished gene expression pattern from the normal thymus and they are characterized by deregulations of a series of biofunctions, which may be involved in the development of neuroendocrine tumor. This study hence has provided not only a detailed comprehension of the molecular pathogenesis of thymic carcinoid with ectopic ACTH syndrome, but also a road map to approach thymic neuroendocrine tumors at the system level. Transcriptome profilings were performed to identify differentially expressed cDNAs between five samples (NCs) from thymic tumor-suffering patients with ectopic ACTH syndrome (i.e., NC1, NC2, NC3, NC4, NC5, NC6) and six samples (ACs) of the noncancerous thymuses (i.e., AC1, AC2, AC3, AC4, AC5).
Project description:Background: It is still uncertain whether carcinoids of the lung and gastrointestinal (GI) tract have a common origin or whether they are closer in origin to carcinomas of the same organs. MicroRNA (miRNA) expression may clarify their nature and origin. Methods: First, to verify whether formalin-fixed paraffin-embedded (FFPE) samples retain the expression signature of the tissue, miRNA expression was compared between FFPE and frozen samples. Second, we selected surgically resected FFPE samples of pulmonary and GI carcinoids, as well as other types of tumors and normal tissues from each organ, and we compared the comprehensive expression patterns of miRNAs by microarray. These data were analyzed by hierarchical clustering and consensus clustering with non-negative matrix factorization (NMF). Results: The miRNA expression profiles of FFPE and frozen samples correlated quite well. In the first hierarchical clustering, most of the carcinoids formed one major cluster with loose subpartitioning into each organ type, while the second major cluster mainly comprised adenocarcinomas and normal tissues. The NMF approach largely supported hierarchical clustering. In the additional cluster analysis comparing carcinoids to small-cell lung carcinomas (SCLCs), carcinoids formed a distinct cluster, while SCLCs grouped together with pulmonary adenocarcinomas and normal lung tissues in another major cluster. Furthermore, we found some miRNAs that exhibited significant expression in carcinoids. Conclusion: Carcinoids had a characteristic pattern of miRNA expression, suggesting a common origin for pulmonary and GI carcinoids. The expression profiles were different in carcinoids and SCLCs, indicating distinct histogenesis of these neuroendocrine tumors.