Heat shock protein 27 was up-regulated in cisplatin resistant human ovarian tumor cell line and associated with the cisplatin resistance

To understand the molecular basis for failure of cisplatin (CDDP) based che motherapy, we compared gene expressions between CDDP sensitive and resistan t ovarian tumor cell line, 2008 and 2008/C13*5.25, by mRNA differential dis play. We detected both up-regulated and down-regulated bands in the resista nt cell and found some of them to be positive on Northern blotting, DNA seq uencing revealed one to be mitochondrial heat shock protein 75. We found th at HSP27 and HSP70 were also up-regulated in the resistant cell by Western blotting. Further, transient transfection with the HSP27 sense gene made th e sensitive cell more resistant, while transient transfection with the anti sense gene made it more sensitive. (C) 2001 Elsevier Science Ireland Ltd. A ll rights reserved.