Project description:Recent studies have shown that circular RNAs (circRNAs) are abundant, widely expressed in mammals, and can display cell-type specific expression. However, how production of circRNAs is regulated and their precise biological function remains largely unknown. To study how circRNAs might be regulated during colorectal cancer progression, we used three isogenic colon cancer cell lines that differ only in KRAS mutation status. Cellular RNAs from the parental DLD-1 cells that contain both wild-type and G13D mutant KRAS alleles and isogenically-matched derivative cell lines, DKO-1 (mutant KRAS allele only) and DKs-8 (wild-type KRAS allele only) were analyzed using RNA-Seq. We developed a bioinformatics pipeline to identify and evaluate circRNA candidates from RNA-Seq data. Hundreds of high-quality circRNA candidates were identified in each cell line. Remarkably, circRNAs were significantly down-regulated at a global level in DLD-1 and DKO-1 cells compared to DKs-8 cells, indicating a widespread effect of mutant KRAS on circRNA abundance. This finding was confirmed in two independent colon cancer cell lines HCT116 (KRAS mutant) and HKe3 (KRAS WT). In all three cell lines, circRNAs were also found in secreted extracellular-vesicles, and circRNAs were more abundant in exosomes than cells. Our results suggest that circRNAs may serve as promising cancer biomarkers.
Project description:Fibroblasts isolated from human colon submucosal and subperitoneal layer were stimulated by colon cancer cell line (DLD-1) cultured medium. Peritoneal invasion in colon cancer is an important prognostic factor, and the fibrosis with α-SMA was a significant pathological feature of the cancer microenvironment formed by peritoneal invasion (CMPI). The result indicated that the gene expression of subperitoneal fibroblasts showed more various gene modification than submucosal fibroblasts. And ACTA2 expression was higher in fibroblasts from subperitoneal layer than that from submucosal layer. Together with this concordant stromal protein expression in CMPI, this in vitro model is able to reflect the special microenvironment in CMPI. 3 cases of human colon submucosal and subperitoneal fibroblasts were isolated, and these fibroblasts were stimulated with DLD-1 cultured medium. Total RNA were extracted from these samples and hybridized in Affymetrix microarray to compare their gene expression changes through the DLD-1 stimulation
Project description:Gene expression profile of two reporgrammed cell lines iPSC CRL1831 (induced pluripotent stem cells) and CSC DLD1 (cancer stem-like cells) derived from normal colon CRL1831 and colorectal cancer DLD-1 cells, after transfer to 3D cell culture conditions and cell lines treated with single or fractionated ionizing radiation doses under 3D cell culture conditions. There are no data that cancer metastases arise due to specific mutations of cancer cells. Therefore ongoing investigation of reprogrammed cancer cells grown in three-dimensional (3D) cell culture models might provide researchers with essential data studying tumor oncogenesis and metastases formation. 3D culture models were shown to mimic in vivo cell microenvironment more accurately than the standard two-dimensional cell monolayer (2D) cultures. Also, growing evidence suggests that 2D and 3D cultured cells gene expression pattern variance following irradiation is highly dependent on cancer cell state and their interaction with microenvironment.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.