Abstract

Colon cancer is the third most common cancer worldwide. Conventional therapies have shown moderate efficacy with severe adverse effects, therefore there is an urgent need for safer alternatives. In this study, Cistanche tubulosa, local name Thanoon, was considered as a potential phytotherapeutic strategy because of its known high therapeutic potential in traditional medicine and wide abundance in the Middle East region. Bioactive compounds were extracted from powdered C. tubulosa and tested for their anticancer properties against four colon cancer cell lines including two derived from primary tumor (CaCo2 and HCT116) and two derived from metastatic site (LoVo and SW620). Effect of C. tubulosa on induction of apoptosis and cellular redox homeostasis were also investigated. C. tubulosa exhibited a concentration and time-dependent inhibition of proliferation of all tested cancer cell lines by more than 60% upon 72 hours treatment with 1 mg/mL of crude extract. Inhibition of proliferation was marked by induction of apoptosis, intracellular reactive oxygen species production and mitochondrial superoxides. This data suggest that C. tubulosa is a promising candidate for additive anti-colon cancer therapy. This is the first study showing anticancer bioactivity of C. Tubulosa against colon cancer cells.

Key words: Cistanche tubulosa, colon cancer, redox homeostasis, anticancer bioactivity