Adiponectin receptor agonist AdipoRon induces apoptotic cell death and suppresses proliferation in human ovarian cancer cells.

Abstract

We tested the hypothesis that stimulation of adiponectin receptors with the synthetic agonist AdipoRon suppresses proliferation and induces apoptotic death in human high grade serous ovarian tumor cell lines and in ex vivo primary tumors, mediated by activation of 5' AMP-activated protein kinase (AMPK) and inhibition of mechanistic target of rapamycin (mTOR). We determined the effect of AdipoRon on high grade serous ovarian tumor cells lines (OVCAR3, OVCAR4, A2780) and ex vivo primary tumor tissue. Western blotting analysis was performed to examine changes in activation of AMPK and mTOR signaling and flow cytometry was utilized to examine changes in cell cycle progression. Immunofluorescence of cleaved caspase-3 positive cells and flow cytometry of annexin V positive cells were used to determine changes in apoptotic response. The CyQUANT proliferation assay was used to assess cell proliferation. AdipoRon treatment increased AMPK phosphorylation (OVCAR3 P = 0.01; A2780 P = 0.02) but did not significantly alter mTOR activity. AdipoRon induced G1 cell cycle arrest in OVCAR3 (+ 12.1%, P = 0.03) and A2780 (+ 12.0%, P = 0.002) cells. OVCAR3 and OVCAR4 cells treated with AdipoRon underwent apoptosis based on cleaved caspase-3 and annexin V staining. AdipoRon treatment resulted in a dose dependent decrease in cell number versus vehicle treatment in OVCAR3 (-61.2%, P < 0.001), OVCAR4 (-79%, P < 0.001), and A2780 (-56.9%, P < 0.001). Ex vivo culture of primary tumors treated with AdipoRon resulted in an increase in apoptosis measured with cleaved caspase-3 immunohistochemistry. AdipoRon induces activation of AMPK and exhibits an anti-tumor effect in ovarian cancer cell lines and primary tumor via a mTOR-independent pathway.

• Authors: Amin A Ramzan, Benjamin G Bitler, Douglas Hicks, Kelsey Barner, Lubna Qamar, Kian Behbakht, Theresa Powell, Thomas Jansson, Heidi Wilson
• Journal: Molecular and cellular biochemistry (Mol Cell Biochem) Vol. 461 Issue 1-2 Pg. 37-46 (Nov 2019) ISSN: 1573-4919 [Electronic] Netherlands
• PMID: 31292831 (Publication Type: Journal Article)

Chemical References

• AdipoRon
• Piperidines
• Receptors, Adiponectin
• Mechanistic Target of Rapamycin Complex 1
• AMP-Activated Protein Kinases

Topics

• AMP-Activated Protein Kinases (metabolism)
• Apoptosis (drug effects)
• Cell Cycle Checkpoints (drug effects)
• Cell Line, Tumor
• Cell Proliferation (drug effects)
• Female
• Humans
• Mechanistic Target of Rapamycin Complex 1 (metabolism)
• Mitosis (drug effects)
• Models, Biological
• Neoplasm Grading
• Neoplasms, Cystic, Mucinous, and Serous (enzymology, pathology)
• Ovarian Neoplasms (enzymology, pathology)
• Piperidines (pharmacology)
• Receptors, Adiponectin (agonists, metabolism)