MiR-130a activates apoptotic signaling through activation of caspase-8 in taxane-resistant prostate cancer cells [miRNA]

ABSTRACT: Background: The acquisition of drug resistance is one of the most malignant phenotypes of cancer. MicroRNAs (miRNAs) have been implicated in various types of cancers, but its role in taxane-resistance of prostate cancer remains poorly understood. Methods: In order to identify miRNAs related to taxane-resistance, miRNA profiling was performed using prostate cancer PC3 cells and paclitaxel-resistant PC3 cell lines established from PC3 cells. Microarray analysis of mRNA expression was also conducted to search for potential target genes of miRNA. The effects of ectopic expression of miRNA on cell growth, tubulin polymerization, drug sensitivity and apoptotic signaling pathway were investigated in a paclitaxel-resistant PC3 cell line. Results: The expression of miR-130a was down-regulated in all paclitaxel-resistant cell lines compared with parental PC3 cells. Based on mRNA microarray analysis, we identified SLAIN1 and CAV2 as potential target genes for miR-130a. Transfection with a miR-130a precursor into a paclitaxel-resistant cell line suppressed cell growth and increased the sensitivity to paclitaxel. Lastly, ectopic expression of miR-130a did not affect the polymerized tubulin level, but activated apoptotic signaling through activation of caspase-8. Conclusion: These results suggested that miR-130a may be involved in the paclitaxel-resistance and could be a therapeutic target for taxane-resistant prostate cancer. Human hormone-refractory prostate cancer PC3 cells were cultured in RPMI1640 medium supplemented with 10 % of fetal bovine serum, 100 units/ml of penicillin and 100 ug/ml of streptomycin. Paclitaxel-resistant PC3PR20, PC3PR70 and PC3PR200 cells, which respectively could proliferate in the presence of 20, 70 and 200 nM of paclitaxel (Sigma-Aldrich, St. Louis, MO, USA), were previously established from PC3 cells by a stepwise increase of paclitaxel in the culture medium (Kojima et al, 2010, Prostate 70: 1501-12).

ORGANISM(S): Homo sapiens

SUBMITTER: Toshio Kojima 

PROVIDER: E-GEOD-64013 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress