Expression and mechanism of miR-208a in rat myocardial ischemia reperfusion injury and ischemic postconditioning

Abstract:

Objective：To establish hypoxia drug resistance model（HDRM） of human ovarian cancer cell lines A2780 and SKOV3 by chemical induction method of Cobalt Chloride（CoCl2） and to compare the drug resistant characteristics of those two cell lines. Methods：CoCl2 with different concentrations（0，50，100，150，200，300 μmol/L） was added to A2780 and SKOV3 cells for 12，24，48，72 h. Cell proliferation activity（CPA） was detected by methyl thiazolyl tetrazolium（MTT）. MTT was used to detect the drug resistance multiple（DRM） of paclitaxel under the different concentrations of CoCl2. The same cell lines without CoCl2 were taken as normoxic control. CoCl2 with concentration of 150 μmol/L was added to A2780 and SKOV3 cells medium for 24 h respectively and the expression of HIF-1α mRNA was detected by the real time polymerase chain reaction. The same cell lines without CoCl2 were taken as normoxic control. Results：The proliferation activity of A2780 and SKOV3 cells was correlated with CoCl2 in a dose and time dependent manner（A2780 group：F=1 165.416，P＝0.000；SKOV3 group：F=2 802.394，P＝0.000）. Paclitaxel resistance fold of those two kinds of cells was increased with the increase of CoCl2 concentration（F=7 842.711，P＝0.000）. With the same concentration of CoCl2，DRM of SKOV3 cells was significantly higher than that of A2780 cells（50 μmol/L group：t=-48.287，P＝0.000；100 μmol/L group：t=-263.205，P＝0.000；150 μmol/L group：t=-143.305，P＝0.000）. With 150 μmol/L CoCl2 culturing for 24 h，DRM of A2780 and SKOV3 cells reached to 9.84±0.11 and 21.08±0.08，respectively. The increase of HIF-1α mRNA expression in SKOV3 cells was significantly higher than that of A2780 cells（t=-5.573，P＝0.000）. Conclusion：Ovarian cancer HDRM can be successfully established by CoCl2 induction method and DRM is related with cell characteristics. Under the same condition，SKOV3 cell line is easier to establish HDRM than A2780 cell line，and SKOV3 is an ideal cell line for hypoxia resistance reversal study.