Viagra turns the immune system on ? to cancer.
Sildenafil ? Viagra and other “impotence drugs” that can produce an erection ? also shows promise in unmasking cancer cells so the immune system can recognize and attack them, scientists at the Johns Hopkins Kimmel Cancer Center found.
Tests on mice with implanted colon and breast tumors showed tumor size decreased to as much as one third their original size in sildenafil-treated animals, compared to mice that did not get the drug.
Lab-grown cancer cells treated with sildenafil showed similar results, as did tissue samples taken from 14 head and neck cancer and multiple myeloma patients.
The study homes in on a tactic used by cancers to avoid detection by the immune system by turning elements of that system to its own advantage, said Dr. Ivan Borrello, assistant professor at the Johns Hopkins Kimmel Cancer Center.
The report, published in the Journal of Experimental Medicine, showed the drugs dampened a specialized cancer cell that diverts the immune system away from tumors, allowing swarms of cancer-attacking T-cells to migrate to tumor sites in the rodents.
“Impotence drugs won?t cure cancer,” Borello cautioned, “but could be used in addition to standard chemotherapy or immunotherapy treatments.” The investigators are planning human studies to begin in the next year. Funding for the study was provided by the Italian Association for Cancer Research.
