The combined treatment of PDE5 inhibitor Vardenafil and 5 μM EGCG caused a strong reduction of cell viability not only in multiple myeloma, but also in other models as prostate, gastric, pancreatic, breast cancer, and in acute myeloid and chronic lymphocytic leukemia cell lines [74,164,165]. The gene discussed is PDE5A; the disease is plasma cell myeloma.