Heat shock protein 90α inhibitor, PU-H71 in combination with DHEA promoting apoptosis in triple-negative breast cancer cell line MDA-MB-231.

Due to the lack of markers (ER, PR, and HER-2/Neu) for the molecular-targeted therapies triple-negative breast cancer (TNBC) is more challenging than other subtypes of breast cancer. Moreover, the conventional chemotherapeutic agents are still the mainstay of most therapeutic protocols and eventually turn into a refractory drug-resistance , hence, more efficient therapeutic regimens are urgently required. The present study aimed to elucidate the effects of PU-H71 combined with DHEA on triple-negative breast cancer cell line MDA-MB-231 and to assess the synergy using the Chou-Talalay method. The combined therapy controlled the expression of an array of antioxidants and metabolizing enzymes, leading to the induction of oxidative stress which in turn induced apoptotic cell death. Our results indicated that the combined treatment with PU-H71 and DHEA exerts a synergistic anti-tumor effect on MDA-MB-231 triple-negative breast cancer cell line.