Researchers say mouse models and data from 5 million health fund members show sildenafil (the active ingredient in Viagra), in combination with statins, can improve outcomes by blocking the supply of cholesterol that cancer cells need to metastasize.

https://www.timesofisrael.com/in-world-first-israeli-scientists-find-active-ingredient-in-viagra-may-stop-cancer-spread/

https://aacrjournals.org/cancerres/article/doi/10.1158/0008-5472.CAN-26-1818/786876/PDE5a-Inhibition-Restricts-Cancer-Metastasis-by