Weizmann Institute researchers found sildenafil curbed the metastatic cascade—not primary tumor growth—with lung metastases falling in mouse models across several cancer types.
PDE5A inhibition drove up cGMP, which blocked the NPC1 cholesterol transporter, trapping cholesterol inside tumor cells, disrupting mitochondrial function and membrane lipid rafts, and starving cells of energy needed to migrate.
5 million health records covering 40,567 male cancer patients showed better five-year survival among Viagra users, with a dose-response pattern that strengthened when statins were also used.
The Viagra-statin pairing created a “metabolic trap” by blocking both cholesterol export and production, delivering the lowest cell migration in lab tests and the lowest metastatic burden in mice.
Metastasis causes about 90% of cancer deaths, but the human evidence here is retrospective, so prospective trials are still needed before the repurposed combination can be adopted in oncology.