Meta-Analysis
Copyright ©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. May 15, 2024; 16(5): 2168-2180
Published online May 15, 2024. doi: 10.4251/wjgo.v16.i5.2168
Association of complement components with risk of colorectal cancer: A systematic review and meta-analysis
Xiao-Lin Zhu, Lu Zhang, Su-Xia Qi
Xiao-Lin Zhu, Su-Xia Qi, Department of Gastroenterology, Qingdao Municipal Hospital, Qingdao 266071, Shandong Province, China
Lu Zhang, Department of Medical Administration, Qingdao Municipal Hospital, Qingdao 266071, Shandong Province, China
Author contributions: Zhu XL and Qi SX designed the project; Zhu XL and Zhang L performed the literature search, data acquisition, and data extraction, and supported the writing of the paper; Zhu XL performed the statistical analyses; all authors read and approved the final manuscript.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Su-Xia Qi, MA, Department of Gastroenterology, Qingdao Municipal Hospital, No. 5 Donghai Middle Road, Qingdao 266071, Shandong Province, China. qisuxia_0@163.com
Received: December 15, 2023
Peer-review started: December 15, 2023
First decision: December 22, 2023
Revised: January 11, 2024
Accepted: March 4, 2024
Article in press: March 4, 2024
Published online: May 15, 2024
Abstract
BACKGROUND

Complement components could contribute to the tumor microenvironment and the systemic immune response. Nevertheless, their role in colorectal cancer (CRC) remains a contentious subject.

AIM

To elucidate the relationship between complement components and CRC risk and clinical characteristics.

METHODS

Searches were conducted in PubMed, the Cochrane Library, and the China National Knowledge Infrastructure database until June 1, 2023. We included cohort studies encompassing participants aged ≥ 18 years, investigating the association between complement components and CRC. The studies were of moderate quality or above, as determined by the Agency for Healthcare Research and Quality. The meta-analysis employed fixed-effects or random-effects models based on the I² test, utilizing risk ratio (RR) and their corresponding 95% confidence interval (CI) for outcomes. Sensitivity and subgroup analyses were performed to validate the robustness of the collective estimates and identify the source of heterogeneity.

RESULTS

Data from 15 studies, comprising 1631 participants that met the inclusion criteria, were included in the meta-analysis. Our findings indicated that protein levels of cluster of differentiation 46 (CD46) (RR = 3.66, 95%CI: 1.75-7.64, P < 0.001), CD59 (RR = 2.86, 95%CI: 1.36-6.01, P = 0.005), and component 1 (C1) (RR = 5.88, 95%CI: 1.75-19.73, P = 0.004) and serum levels of C3 (standardized mean difference = 1.82, 95%CI: 0.06-3.58, P = 0.040) were significantly elevated in patients with CRC compared to healthy controls. Strong expression of CD55 or CD59 was associated with a higher incidence of lymph node metastasis, whereas strong CD46 expression correlated with a higher incidence of tumor differentiation compared to low CD46 expression (P < 0.05 for all). Although specific pooled results demonstrated notable heterogeneity, subgroup analyses pointed to regional differences as the primary source of inconsistency among the studies.

CONCLUSION

Our analysis underscores that increased levels of specific complement components are associated with a heightened risk of CRC, emphasizing the potential significance of monitoring elevated complement component levels.

Keywords: Complement components, Colorectal cancer, Lymph node metastasis, Systematic review, Meta-analysis

Core Tip: This meta-analysis provides evidence emphasizing that increased levels of specific complement components are associated with a high risk of colorectal cancer (CRC). Compared with the healthy control group, protein levels of cluster of differentiation 46 (CD46), CD59, and component 1 (C1), and serum levels of C3 were significantly elevated in patients with CRC. Significantly, patients with pronounced expression of CD55 or CD59 have a higher incidence of lymph node metastasis. Nevertheless, these findings emphasize the need for methodologically rigorous studies with larger sample sizes to corroborate these preliminary conclusions.