Inhibition of IRES-dependent translation of caspase-2 by HuR confers chemotherapeutic drug resistance in colon carcinoma cells.

ABSTRACT: HuR plays an important role in tumor cell survival mainly through posttranscriptional upregulation of prominent anti-apoptotic genes. In addition, HuR can inhibit the translation of pro-apoptotic factors as we could previously report for caspase-2. Here, we investigated the mechanisms of caspase-2 suppression by HuR and its contribution to chemotherapeutic drug resistance of colon carcinoma cells. In accordance with the significant drug-induced increase in cytoplasmic HuR abundance, doxorubicin and paclitaxel increased the interaction of cytoplasmic HuR with the 5'untranslated region (5'UTR) of caspase-2 as shown by RNA pull down assay. Experiments with bicistronic reporter genes furthermore indicate the presence of an internal ribosome entry site (IRES) within the caspase-2-5'UTR. Lucifer

SUBMITTER: Badawi A 

PROVIDER: S-EPMC5915078 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature