“…Similarly, the zinc protoporphyrin, another potent HO-1 inhibitor, has an antineoplastic effect in rats and mice bearing tumors derived from hepatoma and human colon cancer cells (9,76) and also reduces vGPCR-induced tumor growth by 80% (data not shown). Recent evidence shows that HO-1 is overexpressed in pancreatic, gastric, lung, and renal cancer, myeloid leukemia, melanoma, glioma, tongue, thyroid, and hepatocarcinomas (8,12,13,60,61,64,65,70,(75)(76)(77)(78)(79)(80)(81)(82)(83), which are some of the cancer types where RhoA is also overexpressed. Although the link between HO-1 expression and aberrant cell growth is starting to be unraveled, metalloporphyrins that inhibit HO-1 deserve further studies as antitumoral drugs.…”