Author(s): Hadil El-burai, Mazen Alzaharna, Rajy Isleem, Mahmoud El-Hindi and Fadel Sharif

Abstract: Colorectal cancer is one of the commonest tumors worldwide, and the third cause of death among all cancers. Over the years, several herbal plants have proved efficacy in modulating this disease. In this study, plant parts of Rosmarinus officinalis, Avena sativa, Punicagranatum and Portulaca oleracea were investigated for their possible antitumor effects. The plants were extracted using Soxhlet using different solvent. Using MTT, the viability of Caco-2 cells wasassessed after treatments with the crude extracts. The most potent extracts were treated in a combination manner with 5-Fluorouracil against Caco-2 and quantified using Chou-Talalay method. Results show that R. officinalis chloroformic and A. sativa ethanolic extracts have given the best antiproliferative and cytotoxic effects with IC₅₀ 77 and 67 μg/ml, respectively. Combination experiments of those extracts with 5-Fluorouracil have shown various synergies. The two extracts show potentiality for cancer therapy; however, further studies needed to assess their active components and their effects in vivo.