Isorhamnetin is a phytochemical present in many plants and is also a metabolite of quercetin, which is known to reduce the risk of cancer. There are a few studies which demonstrate similar activity for the isorhamnetin and its glycosides. Researchers, led by Lee HJ, investigated the anticancer effect of isorhamnetin on cultured lung cancer cells and on mice with lung cancer . Their in-vitro study showed that isorhamnetin induced apoptosis, which is mediated by a mitochondria-dependent caspase activation. Their in-vivo test confirmed the anticancer effect of isorhamnetin: injection of the mice with isorhamnetin significantly reduced the weights of tumors. Also in this in-vivo test the researchers found that isorhamnetin acted through caspases-mediated apoptosis.
Another Chinese in-vitro study, lead by Ma G of Sichuan University, concluded that isorhamnetin appears to be a potent drug against esophageal cancer due to its potential to inhibit proliferation and induce apoptosis of cultured esophageal cancer cells . Isorhamnetin significantly reduced the viability of the cancer cells, increased the number of cells in the G(0)/G(1) phase and induced typical apoptotic morphology.
Bao M and co-workers of the East China University of Science and Technology were the first to demonstrate the anticancer effect of isorhamnetin against human liver carcinoma cells. They used isorhamnetin isolated from the traditional Chinese medicine Sea Buckthorn .
 Lee HJ, Lee HJ, Lee EO, Ko SG, Bae HS, Kim CH, Ahn KS, Lu J, Kim SH. " Mitochondria-cytochrome C-caspase-9 cascade mediates isorhamnetin-induced apoptosis." Cancer Letters. 2008 July 8.
 Ma G, Yang C, Qu Y, Wei H, Zhang T, Zhang N. "The flavonoid component isorhamnetin in vitro inhibits proliferation and induces apoptosis in Eca-109 cells."
Chemico-Biological Interactions. 2007 April 25;167(2):153-60.
The Medicine-Biology Laboratory of Life Science, College of Sichuan University, Chengdu, Sichuan Province 610041, People's Republic of China.
 Teng BS, Lu YH, Wang ZT, Tao XY, Wei DZ." In vitro anti-tumor activity of isorhamnetin isolated from Hippophae rhamnoides L. against BEL-7402 cells." Pharmacological Research. 2006 September;54(3):186-94.