Colorectal cancer (CRC) is a leading cause of cancer-related death worldwide due to the lack of effective diagnosis and prognosis biomarkers and therapeutic targets, resulting in poor patient survival rates. Circular RNA (circRNA) is a type of endogenous non-coding RNA (ncRNA) with a closed-loop structure that plays a crucial role in physiological processes and pathological diseases. Recent studies indicate that circRNAs are involved in the diagnosis, prognosis, drug resistance, and development of tumors, particularly in CRC. Therefore, circRNA could be a potential new target for improving CRC diagnosis, prognosis, and treatment. This review focuses on the origin and biological functions of circRNA, summarizes recent research on circRNA’s role in CRC, and discusses the potential use of circRNAs as clinical biomarkers for cancer diagnosis and prognosis, as well as therapeutic targets for CRC treatment.

Background and objectives: Anastomotic leakage (AL) is a common postoperative complication of rectal cancer, and the reinforced efficacy of the suture is still contentious. This study aimed to investigate the safety and effectiveness of anastomotic reinforcement suture in the prevention of anastomotic leakage after rectal cancer surgery using the Meta method. Methods: We searched eight major databases (PubMed, Embase, Cochrane Library, Sinomed, Web of Science, Wanfang, VIP, and CNKI) in July 2022 to perform a meta-analysis to evaluate the efficacy of anastomotic reinforcement suture after rectal cancer surgery. The primary outcome measures were anastomotic leakage rate, anastomotic bleeding rate, and infection rate. Results: A total of 10 articles and 1573 subjects were included in the study, including 754 cases in the reinforced suture group and 819 cases in the unreinforced suture group. The results showed that compared to the unreinforced suture, the incidence of anastomotic leakage was less (OR = 0.27, 95% CI 0.17-0.41, P < 0.001) and the incidence of infection was less (OR = 0.43, 95% CI 0.21-0.88, P < 0.05), shorter hospital stay (MD = -0.57, 95% CI -1.15-0.00, P≤0.05), earlier anal exhaust time (MD = -0.3, 95% CI -0.23--0.03, P < 0.05). The operative time (MD = 18.79, 95% CI: 13.57-24.01, P < 0.001) was higher than that of the unreinforced suture group. There were no significant differences in intraoperative blood loss (MD = 0.45, 95% CI -6.96-7.87, P > 0.05), incidence of anastomotic bleeding (OR = 0.44, 95% CI 0.13-1.44, P > 0.05), and incidence rates of intestinal obstruction (OR = 0.71, 95% CI 0.32-1.57, P > 0.05). Conclusions: Existing studies indicate that anastomotic reinforcement suture can significantly reduce the incidence of anastomotic leakage, which has the value of clinical promotion. However, this conclusion still needs multicenter high-quality RCTs with a large sample size to further confirm.