Androgen deprivation therapy (ADT) can lead to metabolic syndrome (MS) and is implicated in ADT-resistance. Metformin showed antineoplastic activity through mTOR inhibition secondary AMPK-activation.
To investigate whether metformin mitigated ADT-related MS, we conducted a randomized double-blind phase II trial of metformin 500 mg TID or placebo in non-diabetic patients with biochemically-relapsed or advanced PC due for ADT. Fasting serum glucose, insulin, PSA, metformin, weight and waist circumference (WC) were measured at baseline, week 12 and 28. The primary endpoint was a group of MS metrics. Secondary endpoints include PSA response, safety, serum metformin concentrations and analysis of downstream an mTOR target, phospho-S6-kinase.
36 men were randomized to either metformin or placebo. Mean age was 68.4. Mean weight, WC and insulin levels increased in both arms. At week 12 and 28, no statistical differences in weight, WC or insulin were observed in either arm. No significant difference in percentage of patients with PSA <0.2 at week 28 between metformin (45.5%) vs. placebo (46.7%). Analysis in the metformin-arm showed variable down-regulation of phospho-S6 kinase.
In our small study, metformin added to ADT did not show a reduced risk of ADT-related MS or differences in PSA response.
Oncotarget. 2023 Jun 19*** epublish ***
Devalingam Mahalingam, Salih Hanni, Anthony V Serritella, Christos Fountzilas, Joel Michalek, Brian Hernandez, John Sarantopoulos, Paromitta Datta, Ofelia Romero, Sureshkumar Mulampurath Achutan Pillai, John Kuhn, Michael Pollak, Ian M Thompson
Division of Hematology and Oncology, University of Texas Health Science Center, San Antonio, TX 77030, USA., Robert H Lurie Comprehensive Cancer Center of Northwestern University, Chicago, IL 60611, USA., Institute for Drug Development, Mays Cancer Center at University of Texas Health, San Antonio, TX 78229, USA., Audie Murphy VA Hospital, San Antonio, TX 78229, USA., Division of Experimental Medicine, Lady Davis Institute of Medical Research, Jewish General Hospital, McGill University, Montreal, Canada.