Inhibiting Mitophagy as a Novel Mechanism to Kill Prostate Cancer Cells
Abstract
The planned research proposes to examine the ability of inhibition of mitophagy, the mitochondrial-specific form of autophagy, to kill prostate cancer cells. Cancer cells become increasingly dependent on mitophagy as an energy source and the mitochondria themselves become more and more dysfunctional. Therefore, mitophagy may represent a novel target for the prevention of prostate cancer progression. Consequently, the purpose of this research is to test whether inhibition of mitophagy can lead to the death of prostate cancer cells. Key mediators of the mitophagic process, specifically Parkin, dynamin-related protein-1 (Drp1), fission-1 (Fis1), and cyclophilin-D (CypD), will be genetically disrupted by shRNA. The effects that mitophagy blockade has on mitochondrial function, ROS production and ultimately survival of normal prostate cells as well as several different prostate cancer cell lines, especially highly aggressive cells, will then be examined. We experienced considerable problems with the shRNA approach but have successfully circumvented this using siRNAs, such that we now have efficient knockdown of each protein in DU145, LNCaP and PC3 prostate cancer cells. Knockdown of CypD beneficially affected mitochondrial function and reduced reactive oxygen species production (ROS), suggesting that CypD may not be a viable target for the treatment of prostate cancer. In contrast, targeting of Fis1 and especially Drp1 maybe of therapeutic benefit as they were found to induce mitochondrial dysfunction and/or ROS production along with a compensatory increase in general autophagy. We are currently recapitulating these studies in the Parkin-deficient prostate cancer cells and will then test whether the disruption of Fis1, Drp1 and Parkin can sensitize the prostate cancer cells to paclitaxel exposure.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 2013
- Accession Number
- ADA590679
Entities
People
- Christopher P. Baines
Organizations
- University of Missouri