Project description:MicroRNA (miRNA) expression profiles for lung cancers were examined to investigate the miRNA involvement in lung carcinogenesis. miRNA microarray analysis identified statistical unique profiles, which could discriminate lung cancers from noncancerous lung tissues.
Project description:Acute myeloid leukemia (AML) carrying NPM1 mutations and cytoplasmic nucleophosmin (NPMc+ AML) accounts for about one-third of adult AML and shows distinct features, including a unique gene expression profile. MicroRNAs (miRNAs) are small noncoding RNAs of 19-25 nucleotides in length that have been linked to the development of cancer. Here, we investigated the role of miRNAs in the biology of NPMc+ AML. The miRNA expression was evaluated in 85 adult de novo AML patients characterized for subcellular localization/mutation status of NPM1 and FLT3 mutations using a custom microarray platform. Data were analyzed by using univariate t test within BRB tools. We identified a strong miRNA signature that distinguishes NPMc+ mutated (n = 55) from the cytoplasmic-negative (NPM1 unmutated) cases (n = 30) and includes the up-regulation of miR-10a, miR-10b, several let-7 and miR-29 family members. Many of the down-regulated miRNAs including miR-204 and miR-128a are predicted to target several HOX genes. Indeed, we confirmed that miR-204 targets HOXA10 and MEIS1, suggesting that the HOX up-regulation observed in NPMc+ AML may be due in part by loss of HOX regulators-miRNAs. FLT3-ITD+ samples were characterized by up-regulation of miR-155. Further experiments demonstrated that the up-regulation of miR-155 was independent from FLT3 signaling. Our results identify a unique miRNA signature associated with NPMc+ AML and provide evidence that support a role for miRNAs in the regulation of HOX genes in this leukemia subtype. Moreover, we found that miR-155 was strongly but independently associated with FLT3-ITD mutations.
Project description:MicroRNA miRNA expression profiles for human ovarian carcinomas were examined to investigate the miRNA involvement in the development of this neoplasia. miRNA microarray analysis identified statistical unique profiles, which could discriminate ovarian carcinomas from noncancerous ovarian tissues, and different groups of tumors classified according to histo-pathological characteristics.
Project description:microRNA expression microarray data for analysis of BAALC- and ERG-related miR-expression signatures in older patients with cytogenetically normal AML. The signal intensity was calculated for each spot making an adjustment for local background (i.e., mean foreground minus the median background). Signal intensities less than one were set equal to one and then log-transformed. Log-intensities from replicate spots were averaged. Quantile normalization was performed on arrays using all human and mouse microRNA probes represented on the array. For each microRNA probe, an adjustment was made for batch effects (ie, differences in expression related to the batch in which arrays were hybridized). The normalized data has not been submitted to ArrayExpress.