Project description:Triple-negative breast cancer (TNBC) is the most aggressive form of breast cancer due to lack of effective targeted therapies. Here, we report that the expression of miR-4417 is suppressed during the progression of TNBC cells from non-malignant to the malignant stage. miR-4417 is localized to chromosome 1p36, a region with high loss of heterozygosity in multiple cancers, and its biogenesis is DICER-dependent. Low expression of miR-4417 is significantly associated with worse prognosis in TNBC patients, while overexpression of miR-4417 is sufficient to inhibit migration and tumorigenecity of TNBC cells in vitro. Overall, our findings suggest that miR-4417 exerts a tumor suppressive effect and thereby could serve as a prognostic biomarker and therapeutic tool against TNBC. We used microarrays to profile the global miRNA changes during EMT to identify putative tumor suppressors and prognostic biomarkers for TNBC.
Project description:DNA oligonucleotide microarrays were designed with 307 probes for 96 internal transcribed spacer (ITS1, located between 18S and 26S rRNA genes) sequences of known species and strains from the genus Pseudo-nitzschia (Bacillariophyceae). In addition, microarrays also carried 1893 probes targeting ITS1 aequences of marine Crenarchaeota and Alphaproteobacteria of SAR11 clade. In order to assign microarray profiles to Pseudo-nitzschia ribotypes and species and to 'train' the data analysis system, we grew cultures of Pseudo-nitzschia in the laboratory with identities confirmed through rDNA sequence analysis. In total, 9 cultures and 35 environmental water samples were hybridized to microarrays, in some cases, in duplicate or triplicate. Analysis of microarray data allowed us to identify and map Pseudo-nitzschia spp. in the coastal waters along Washington and Oregon coast of the Eastern Pacific Ocean, and to observe seasonal changes in diatom community composition.
Project description:Transcriptional profiling of Pichia angusta NCYC 495 leu1.1 cells growing exponentially on mineral medium containing 0.5% glucose versus a shift for 2 hours to mineral medium containing 0.5% methanol.