The antipsychotic chlorpromazine suppresses YAP signaling, stemness properties, and drug resistance in breast cancer cells

In this study, we identified that the antipsychotic chlorpromazine (CPZ) exhibited potent anti-breast cancer and anti-CSC capabilities. Treatment with CPZ suppressed stemness properties including mammosphere formation, aldehyde dehydrogenase (ALDH) activity, and stemness-related gene expressions in breast cancer cells and CSCs. Moreover, CPZ increased the susceptibility of breast cancer MCF7 cells and drug-resistant MCF7/ADR cells when combined with chemotherapies. Mechanistically, we identified that CPZ suppressed yes-associated protein (YAP) through modulating Hippo signaling and promoting proteasomal degradation of YAP. Elevated expression of YAP was confirmed to be crucial for stemness-related gene expressions, and was associated with invasiveness and stem-like signatures in breast cancer patients. Moreover, overexpression of YAP conferred poor outcomes particularly of basal-like breast cancer patients. Our data showed that YAP is a promising therapeutic target for breast CSCs, and CPZ has the potential to be a repurposed drug for breast cancer treatment.
Source: Chemico Biological Interactions - Category: Biochemistry Source Type: research