Celastrol inhibits colorectal cancer through TGF-β1/Smad signaling

BACKGROUND: There are few clinical challenges associated with the treatment of colorectal cancer (CRC). Studies have shown that TGF-β plays a crucial role in CRC. Importantly, celastrol, a major components of the root extract of the traditional Chinese herb Tripterygium wilfordii Hook F, has been shown to inhibit the growth, adhesion, and metastasis of human CRC cells through the inhibition of TGF-β1/Smad signaling. MATERIALS AND METHODS: Real-time PCR and Western blot tests were proceeded to present TGF-β1, TGF-β receptor type I (TGFβRI), TGF-β receptor type II (TGFβRII), Smad2/3, p-Smad2/3, Smad4, and glyceraldehyde-3-phosphate dehydrogenase expression in human colon cancer cell samples. RESULTS: Our results indicated that celastrol can reduce the expression levels of TGF-β1, TGFβRI, and TGFβRII in HCT116 and SW620 cells. Furthermore, celastrol could also prevent the increase in Smad4 and p-Smad2/3 in HCT116 and SW620 cells. CONCLUSION: Celastrol could inhibit tumor growth through TGF-β1/Smad signaling and might be a promising therapeutic component against CRC.