Study of Oral Metronidazole on Postoperative Chemotherapy in Colorectal Cancer

Gut microbiota are linked to chronic inflammation and carcinogenesis. Chemotherapy failure is the major cause of recurrence and poor prognosis in colorectal cancer patients. Previously in the investigators' research, the investigators find the contribution of gut microbiota to chemoresistance in patients with colorectal cancer. The investigators found that Fusobacterium nucleatum (Fn) was abundant in colorectal cancer tissues in patients with recurrence post chemotherapy, and was associated with patient clinicopathological characterisitcs. Furthermore, the investigators' bioinformatic and functional studies demonstrated that Fn promoted colorectal cancer resistance to chemotherapy. Metronidazole has been known to treat with anaerobe infection, including Fusobacterium. So oral metronidazole would be used to reduce the abundance of Fn in patients with high Fn, so as to explore whether oral metronidazole can improve the efficacy of postoperative chemotherapy in patients with colorectal cancer.