Abstract
This study aimed to evaluate the effects of mitochondrial pyruvate carrier (MPC) blockade on the sensitivity of detection and radiotherapy of prostate cancer (PCa).
We investigated glycolysis reprogramming and MPC changes in patients with PCa by using metabolic profiling, RNA-Seq, and tissue microarrays. Transient blockade of pyruvate influx into mitochondria was observed in cellular studies to detect its different effects on prostate carcinoma cells and benign prostate cells. Xenograft mouse models were injected with an MPC inhibitor to evaluate the sensitivity of 18F-fluorodeoxyglucose positron emission tomography with computed tomography and radiotherapy of PCa. Furthermore, the molecular mechanism of this different effect of transient blockage towards benign prostate cells and prostate cancer cells was studied in vitro.
MPC was elevated in PCa tissue compared with benign prostate tissue, but decreased during cancer progression. The transient blockade increased PCa cell proliferation while decreasing benign prostate cell proliferation, thus increasing the sensitivity of PCa cells to 18F-PET/CT (SUVavg, P = 0.016; SUVmax, P = 0.03) and radiotherapy (P < 0.01). This differential effect of MPC on PCa and benign prostate cells was dependent on regulation by a VDAC1-MPC-mitochondrial homeostasis-glycolysis pathway.
Blockade of pyruvate influx into mitochondria increased glycolysis levels in PCa but not in non-carcinoma prostate tissue. This transient blockage sensitized PCa to both detection and radiotherapy, thus indicating that glycolytic potential is a novel mechanism underlying PCa progression. The change in the mitochondrial pyruvate influx caused by transient MPC blockade provides a critical target for PCa diagnosis and treatment.
