S-allylmercaptocysteine effectively inhibits the proliferation of colorectal cancer cells under in vitro and in vivo conditions.

S-allylmercaptocysteine (SAMC), one of the water-soluble organosulfur garlic derivatives, has been demonstrated as a suppressive agent against some tumors. The effects of SAMC on the proliferation and metastasis of colorectal cancer (CRC) under in vitro and in vivo conditions were evaluated here. The viabilities and migrations of CRC cells SW480, SW620, Caco-2 treated with SAMC were measured by MTT, scratch-wound, and transwell assays. The in vivo anticancer effect of SAMC against luciferase-expressing SW620 xenografts in mice was determined by bioluminescence imaging and histopathology observation. The apoptosis of SAMC-treated CRC cells was examined by Western blotting. The results demonstrate that SAMC could effectively suppress the growth and metastasis of colorectal cancer cells both in vivo and in vitro. The anticancer effect of SAMC was related to the decreased proliferation and increased apoptosis as well as necrosis of cancer cells. Oral administration of SAMC in the quantity/concentration used had no apparent toxic side effect on the vital organs of the experimental mice. Taken together, the proliferation and metastasis of CRC cells can be significantly suppressed by SAMC treatment under both in vitro and in vivo conditions. SAMC may thus be a promising candidate for CRC chemotherapy.