Triple negative breast cancer (TNBC) accounts for about 10-15% of all breast cancers. It is a heterogeneous disease, characterized by early relapse, aggressive behavior, and poor prognosis, when compared to other breast cancer subtypes. Interestingly, most of the heat shock protein 90 (Hsp90) client proteins are oncoproteins, and some are closely related to the key factors that promote the progression of TNBC. Anacardic acid (AA), which is commonly seen in natural plants of Anacardiaceae, exhibits potent Hsp90 ATPase inhibition activity. In this study, the anticancer effects of AA on TNBC MDA-MB-231 cells were investigated. The results of our study showed that AA inhibited cell proliferation, induced G0/G1-phase cell cycle arrest, suppressed cell invasion and migration, and induced apoptosis in the MDA-MB-231 cells. Regulation of the key Hsp90-dependent tumor-related molecules or endoplasmic reticulum stress (ERS) related molecules, such as GRP78, Hsp70, CDK-4, MMP-9, Bcl-2, and Mcl-1 by AA may be related to these effects. Taken together, our results suggest that AA shows potential as a possible new drug for therapy of TNBC.
Keywords: Anacardic acid; ERS; Hsp90; TNBC; anticancer effect.