Expression and intracellular localization of heat shock proteins in multidrug resistance of a cisplatin resistant human ovarian cancer cell line.

TYK-R10 is a cisplatin resistant human ovarian carcinoma cell line and showed a cross resistance to various anti-cancer drugs including adriamycin (ADR), vincristine (VCR) and etoposide, despite a lack of multidrug phenotype. Under normal conditions, various heat shock proteins (HSPs) were expressed in TYK-R10 but not in parental line (TYK-nu). Non-lethal short-term heat shock treatment induced a high tolerance for cisplatin and VCR in TYK-R10 and ADR, and VCR in TYK-nu. This treatment induced and/or enhanced the expression of various types of HSPs in various intracellular localizations in both TYK-R10 and TYK-nu, with minor differences. These findings indicate that combined expression and intracellular localization of HSPs may play an important role in drug resistance of TYK-R10.