Enhancing Radiation Therapy Response in Prostate Cancer Through Metabolic Modulation by Mito-Lonidamine: A 1H and 31P Magnetic Resonance Spectroscopy Study

Radiation therapy (RT) is the cornerstone treatment for prostate cancer; however, it frequently induces gastrointestinal and genitourinary toxicities that substantially diminish the patients' quality of life. While many individuals experience transient side effects, a subset endures persistent, long-term complications. A promising strategy to mitigate these toxicities involves enhancing tumor radiosensitivity, potentially allowing for lower radiation doses. In this context, mito-lonidamine (Mito-LND), an antineoplastic agent targeting the mitochondrial electron transport chain's complexes I and II, emerges as a potential radiosensitizer. This study investigated Mito-LND's capacity to augment RT efficacy and reduce adverse effects through comprehensive in vitro and in vivo assessments using hormone-sensitive and hormone-refractory prostate cancer models. Employing a Seahorse analysis and ¹H/³¹P magnetic resonance spectroscopy (MRS), we observed that Mito-LND selectively suppressed lactate production, decreased intracellular pH, and reduced bioenergetics and oxygen consumption levels within tumor cells. These findings suggest that Mito-LND remodels the tumor microenvironment by inducing acidification, metabolic de-energization, and enhanced oxygenation, thereby sensitizing tumors to RT. Our results underscore the potential of Mito-LND as a therapeutic adjunct in RT to improve patient outcomes and reduce radiation-associated toxicities in early-stage prostate cancer.