Danggui Buxue Tang potentiates the cytotoxicity of 5‐fluorouracil on colorectal adenocarcinoma cells: A signaling mediated by c‐Jun N‐terminal kinase

Danggui Buxue Tang (DBT) is a well-known Chinese herbal recipe often prescribed in clinical treatment for menopausal and cardiovascular symptoms. 5-Fluorouracil (5-FU) is a chemotherapy drug that treats several cancers; however, it causes severe adverse effects and multidrug resistance. Combining natural medications can reduce the side effects of 5-FU use. Hence, we aimed to determine the role of DBT in strengthening the anticancer capabilities of 5-FU in a cultured colorectal adenocarcinoma cell line (HT-29 cell) and xenograft nude mice. HT-29 cells cultured with DBT did not exhibit cytotoxicity. However, co-administration of DBT with 5-FU significantly increased apoptosis and the expression of apoptotic markers. The inhibition of proliferation induced by DBT and 5-FU was shown to be mediated by c-Jun N-terminal kinase signaling. In addition, the potentiation effect of 5-FU and DBT was demonstrated in reducing tumor size, expressions of Ki67 and CD34 in HT-29 xenograft mice. This finding suggests that DBT can work with 5-FU as a novel chemotherapeutic strategy for treating colon cancer.