Abstract

Previous studies reported the critical role of the brefeldin A–inhibited guanine nucleotide exchange protein 3–prohibitin 2 (BIG3‐PHB2) complex in modulating estrogen signaling activation in breast cancer cells, yet its pathophysiological roles in osteosarcoma (OS) cells remain elusive. Here, we report a novel function of BIG3‐PHB2 in OS malignancy. BIG3‐PHB2 complexes were localized mainly in mitochondria in OS cells, unlike in estrogen‐dependent breast cancer cells. Depletion of endogenous BIG3 expression by small interfering RNA (siRNA) treatment led to significant inhibition of OS cell growth. Disruption of BIG3‐PHB2 complex formation by treatment with specific peptide inhibitor also resulted in significant dose‐dependent suppression of OS cell growth, migration, and invasion resulting from G2/M‐phase arrest and in PARP cleavage, ultimately leading to PARP‐1/apoptosis‐inducing factor (AIF) pathway activation–dependent apoptosis in OS cells. Subsequent proteomic and bioinformatic pathway analyses revealed that disruption of the BIG3‐PHB2 complex might lead to downregulation of inner mitochondrial membrane protein complex activity. Our findings indicate that the mitochondrial BIG3‐PHB2 complex might regulate PARP‐1/AIF pathway–dependent apoptosis during OS cell proliferation and progression and that disruption of this complex may be a promising therapeutic strategy for OS.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.