Project description:To investigate the mechanisms mediating the inhibitory effects of DCC-2036 on LoVo, gene expression profiling analysis using data obtained from RNA-seq of LoVo cells treated with/without DCC-2036.
Project description:LoVo cells were cultured in sEV-depleted (160,000xg, 16h) complete medium and the supernatant were collected after 72h. sEVs were purified and centrifuged at 100,000xg for 2.5h using a Beckman SW41Ti rotor to know the miRNA in LoVo cells and LoVo-Small Extracellular Vesicles
Project description:Six non- and drug-resistant colorectal cancer cell lines were selected in this study, which were non-resistant cell lines: HCT116 and LoVo, four drug-resistant cell lines: HCT116-OxPt, HCT116-SN38, LoVo-OxPt, LoVo-SN38.Proteins extraced from three HCT116 related cell lines were labled and pooled together, and proteins from other three LoVo related cell lines were labled and pooled together.
Project description:PEAK1 overexpression vector and negative control vector were transiently transfected into LoVo cells, respectively, and named LoVo-PEAK1 and LoVo-control groups. LoVo cells of different groups were determined to investigate the different expressions of mRNA using a global gene microarray.
Project description:Irinotecan, an analogue of camptothecin, is frequently used in combination with various anticancer drugs or as a single agent in treatment of colorectal cancer. But drug resistance of tumor is still a major obstacle to overcome for the success of cancer treatment. In this study, We established chronic irinotecan resistant cell line for new marker to increase the sensitivity to irinotecan and investigated gene expression profiles of the irinotecan-resistant colorectal cancer cell line. To create stable CRC cell line chronically resistant to Irinotecan, LoVo cell was exposed to an initial Irinotecan concentration of 0.1 M-NM-<mol/L in RPMI 1640 supplemented with 10% FBS. When the growth of the cultured cells reaches at 80% confluency, cells were passaged twice at same drug concentration to ensure adaptation and then concentration of Irinotecan was sequentially increased in the same manner to 8 M-NM-<mol/L and then we investigated the gene expressions between parental colorectal cancer cell line, LoVo and Irinotecan resistant LoVo cell lines
Project description:Here we exploit the essential process of X-chromosome dosage compensation to elucidate basic mechanisms that control the assembly, genome-wide binding, and function of gene regulatory complexes that act over large chromosomal territories. We demonstrate that a subunit of C. elegans MLL/COMPASS, a gene-activation complex, acts within the dosage compensation complex (DCC), a condensin complex, to target the DCC to both X chromosomes of hermaphrodites and thereby reduce chromosome-wide gene expression. The DCC binds to two categories of sites on X: rex sites that recruit the DCC in an autonomous, sequence- dependent manner, and dox sites that reside primarily in promoters of expressed genes and bind the DCC robustly only when attached to X. We find that DCC mutants that abolish rex-site binding do not eliminate dox-site binding, but instead reduce it to the level observed at autosomal binding sites in wild-type animals. Changes in DCC binding to these non-rex sites occur throughout development and correlate with transcriptional activity of adjacent genes. Moreover, autosomal DCC binding is enhanced by rex-site binding in cis in X-autosome fusion chromosomes. Thus, dox and autosomal sites exhibit similar binding properties. Our data support a model for DCC binding in which low-level DCC binding at dox and autosomal sites is dictated by intrinsic properties correlated with high transcriptional activity. Sex-specific DCC recruitment to rex sites then greatly elevates DCC binding to dox sites in cis, which lack intrinsically high DCC affinity on their own. We also show here that the C. elegans DCC achieves dosage compensation through its effects on transcription.
Project description:The essential process of dosage compensation equalizes X-chromosome gene expression between C. elegans XO males and XX hermaphrodites through a dosage compensation complex (DCC) that resembles condensin. The DCC binds to both X chromosomes of hermaphrodites to repress transcription by half. Here we show that post-translational modification by the SUMO conjugation pathway is essential for sex-specific assembly of the DCC onto X. Depletion of the SUMO peptide in vivo severely disrupts binding of particular DCC subunits and causes changes in X-linked gene expression similar to those caused by disrupting genes encoding DCC subunits. Three DCC subunits are themselves SUMOylated, and depletion of SUMO preferentially reduces their binding to X, suggesting that SUMOylation of DCC subunits is essential for robust association with X. DCC SUMOylation is triggered by the signal that initiates DCC assembly onto X. The initial step of assembly--binding of X-targeting factors to recruitment sites on X (rex sites)--is independent of SUMOylation, but robust binding of the complete complex requires SUMOylation. SUMOylated DCC subunits are enriched at rex sites, and SUMOylation enhances interactions between X-targeting factors and condensin subunits that facilitate DCC binding beyond the low level achieved without SUMOylation. DCC subunits also participate in condensin complexes essential for chromosome segregation, but their SUMOylation occurs only in the context of the DCC. Our results reinforce a newly emerging theme in which multiple proteins of a complex are SUMOylated in response to a specific stimulus, leading to accelerated complex formation and enhanced function.