Platinum-containing compound platinum pyrithione suppresses ovarian tumor proliferation through proteasome inhibition

Abstract

BackgroundOvarian carcinoma is one of the most aggressive gynecological malignant neoplasms and makes up 25–30% of all cancer cases of the female genital tract. Currently, resistance to traditional chemotherapy is a great challenge for patients with Epithelial ovarian cancer (EOC). Therefore, identifying novel agents for EOC treatment is essential and urgent.MethodMTS assay was used to analyze the cell viability and proliferation of cancer cells. Flow cytometry was employed to analyze cell cycle distribution and cell apoptosis. Protein signaling pathways were detected by western blot and immunohistochemical staining. Nude mouse experiment was performed to test the in vivo effect of platinum pyrithione (PtPT).ResultsPtPT is a chemically well-characterized synthetic complex of platinum that potently inhibits proteasome-associated deubiquitinases USP14 and UCHL5 activity and shows selective cytotoxicity to multiple cancer cells without damaging DNA. We found that PtPT significantly accumulated ubquitinated-proteins and suppressed the proliferation of multiple EOC cells. Additionally, PtPT induced G2 phase arrest and apoptosis in both A2780 and SKOV3 cells. More importantly, animal experiments showed that PtPT dramatically suppressed the growth of EOC xenografts without obvious side effects.ConclusionThese results suggest that through proteasome inhibition, PtPT significantly suppressed the proliferation of EOC in vitro and in vivo and could be developed as a novel agent for EOC treatment in the future.

Inhibition of USP14 enhances the sensitivity of breast cancer to enzalutamide

“…This assay was performed as we previously reported [28]. Breast cancer cell was exposed to the indicated treatment and the total proteins were extracted using cell lysis buffer.…”

Targeting proteasome-associated deubiquitinases as a novel strategy for the treatment of estrogen receptor-positive breast cancer

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