Metformin may slow prostate cancer growth

The common diabetes medication metformin helps slow the growth rate of prostate cancer, according to a results of a study presented at the American Association for Cancer Research (AACR) Annual Meeting in Toronto.

Conducted by Princess Margaret Hospital in Toronto, the study followed 22 men with prostate cancer ranging in age from 45 to 70 years.

Researchers assigned patients up to 500 milligrams of metformin three times a day prior to undergoing radical prostatectomy. The median duration of the metformin therapy of 41 days.

“This gave us the ability to compare what the prostate cancer looked like when it was first diagnosed to what it looked like when the prostate cancer was removed from the body,” said Anthony M. Joshua, Ph.D and lead author of the study. “We were able to directly measure the effect of metformin on the prostate cancer.

In addition to reducing the growth rate of the prostate cancer, “Metformin also appeared to reduce one of the main growth pathways that may have contributed to the overall growth of the tumor,” according to Joshua.

Metformin also significantly reduced fasting glucose, insulin growth factor-1, body mass index and waist-to-hip ratio.

Previous laboratory research also had suggested that metformin could slow the growth of cancerous prostate cells.

“This research builds on the hypothesis that metformin has a rule in prostate cancer,” said Joshua. “Exactly what that role will be will depend on the results of the analysis currently being completed by our study team and others worldwide.”

Prostate cancer
Prostate cancer forms in tissues of of the prostate, a gland in the male reproductive system. This type of cancer usually occurs in older men.

Risk factors for prostate cancer include age over 65 years, family history, race, certain prostate changes and certain changes in the chromosomes.

Common urinary symptoms or prostate cancer include not being able to pass urine, having a hard time starting or stopping the urine flow, needing to urinate often, especially at night, weak flow of urine, urine flow that starts and stops, pain or burning during urination.

Other symptoms include blood in the urine or semen, frequent pain in the lower back, hips or upper thighs, and difficulty having an erection.

Sources: American Association for Cancer Research, National Cancer Institute