The involvement of small heat shock protein in chemoresistance in ovarian cancer - in vitro study.

Abstract

Ovarian cancer is the most deadly gynecologic malignancy worldwide. Although the primary response to chemotherapy is high, the majority of patients will develop resistance against applied treatment. In this study, we focused on resistance to cisplatin, a first-line drug used for the treatment of ovarian cancer. The mechanism of the resistance development process is widely described, but there is a lack of information about the involvement of members of small heat shock proteins (HSPs) and their transport via exosomes. In this study, we used two cell lines: A2780 and SKOV3, and their cisplatin-resistance variants: A2780 CDDP and SKOV3 CDDP. We have shown that the expression of three small HSPs (HSPB5, HSPB6, and HSPB8) in cisplatin-resistant cell lines differs from their sensitive counterparts. Further, we isolated exosomes and determined the small HSPs in their cargo. In A2780 WT we observed a low amount of HSPB5 and HSPB6. We did not observe the expression of small HSPs in the SKOV3 cell line in both sensitive and resistant variants. Our data suggest the involvement of small HSPs in drug resistance of ovarian cancer and their presence is not related to exosomal transport. Analysis of the biological consequences of the imbalance of small HSPs expression in cisplatin resistance needs further investigation.