Combining natural products as co-adjuvants in 5-fluorouracil (5-FU) chemotherapy might enhance the effectiveness of 5-FU by avoiding a high dosage and/or reducing treatment times. We explored the anticancer efficacy of the phytosterols (PS) at concentrations achievable in the human colon, as well as their potential as sensitizing agents of human colon cancer cells (Caco-2 and HT-29) to 5-FU treatment. Cells proliferation, combination index, cell cycle, apoptosis, caspases activation, ROS production, and ΔΨm were determined. Co-treatment (PS+5-FU) had an antiproliferative additive effect, and moreover, in general a significantly improved efficacy was observed on cell cycle arrest at S phase, apoptosis induction and increase in caspases activation compared to 5-FU alone, while no significant effects were observed on ROS levels and ΔΨm. Our results suggest, for the first time, the ability of PS to sensitize colon cancer cells to 5-FU chemotherapy and warrant further in vivo studies to confirm our preclinical findings.

在5-氟尿嘧啶（5-FU）化疗中结合使用天然产物作为辅助剂可能会避免高剂量和/或减少治疗时间，从而提高5-FU的疗效。我们探讨了植物固醇（PS）在人结肠中可达到的浓度的抗癌功效，以及它们作为人结肠癌细胞（Caco-2和HT-29）对5-FU治疗的敏化剂的潜力。测定细胞增殖，组合指数，细胞周期，凋亡，胱天蛋白酶激活，ROS产生和Δm。联合治疗（PS + 5-FU）具有抗增殖的加成作用，此外，与单独使用5-FU相比，通常观察到在S期细胞周期停滞，凋亡诱导和胱天蛋白酶激活增加方面，疗效显着提高，而没有观察到对ROS水平和Δm的显着影响。体内研究，以确认我们的临床前发现。