Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jul 21, 2017; 23(27): 5018-5033
Published online Jul 21, 2017. doi: 10.3748/wjg.v23.i27.5018
High expression of anti-apoptotic protein Bcl-2 is a good prognostic factor in colorectal cancer: Result of a meta-analysis
Qi Huang, Shu Li, Pu Cheng, Mei Deng, Xin He, Zhen Wang, Cheng-Hui Yang, Xiao-Ying Zhao, Jian Huang
Qi Huang, Pu Cheng, Mei Deng, Zhen Wang, Cheng-Hui Yang, Jian Huang, Department of Surgical Oncology, the Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Hangzhou 310009, Zhejiang Province, China
Shu Li, Xin He, Xiao-Ying Zhao, Department of Hematology, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310009, Zhejiang Province, China
Author contributions: Li S, Cheng P and Deng M reviewed and screened the articles included in our meta-analysis; Huang Q and He X performed the analysis work needed in this work and draft the manuscript; Wang Z and Yang CH drew the essential diagrams; Zhao XY and Huang J designed the study and edited the manuscript.
Conflict-of-interest statement: The authors deny any conflict of interest.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (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:
Correspondence to: Jian Huang, MD, PhD, Professor, Department of Surgical Oncology, the Second Affiliated Hospital, Zhejiang University School of Medicine, Zhejiang University, Jiefang88 Road, Hangzhou 310009, Zhejiang Province, China.
Telephone: +86-571-87784642 Fax: +86-571-87784642
Received: February 7, 2017
Peer-review started: February 8, 2017
First decision: February 8, 2016
Revised: March 5, 2017
Accepted: April 21, 2017
Article in press: April 21, 2017
Published online: July 21, 2017

To systematically evaluate the prognostic-predictive capability of Bcl-2 in colorectal cancer (CRC).


A systematic literature search was conducted using PubMed, Web of Science and EMBASE databases. Any eligible study must meet the following criteria: (1) bcl-2 expression was evaluated in human CRC tissues by immunohistochemistry; (2) assessment of the relationships between bcl-2 expression and overall survival (OS), disease free survival (DFS), recurrent free survival (RFS) or clinic-pathological characteristics of CRC was included; (3) sufficient information was provided to estimate the hazard ratio (HR) or odds ratio and their 95% confidence intervals (CIs); and (4) the study was published in English. The impact of Bcl-2 expression on survival of CRC patients were evaluated through this meta-analysis.


A total of 40 eligible articles involving 7658 patients were enrolled in our final analysis. We drew the conclusion that Bcl-2 high expression was significantly correlated with favorable OS (pooled HR = 0.69, 95%CI: 0.55-0.87, P = 0.002) and better DFS/RFS (pooled HR = 0.65, 95%CI: 0.50-0.85, P = 0.001). Additionally, the subgroup analysis suggested that Bcl-2 overexpression was significantly associated with prognosis (OS) especially in patients came from Europe and America but not Asian and patients who did not receive any adjuvant therapy before surgery. Finally, our present results indicated that expression of bcl-2 protein was associated with high differentiation grade and A/B Ducks’ stage.


Bcl-2 high expression was significantly correlated with favorable OS and better DFS/RFS. Hence, we propose that Bcl-2 may be a valuable prognostic-predictive marker in CRC.

Keywords: Bcl-2, Colorectal cancer, Meta-analysis, Prognostic, Apoptotic

Core tip: No consensus is available in the literature about the prognostic value of Bcl-2 expression in patients with colorectal cancer (CRC). This is the first systematic review and meta-analysis indicating that Bcl-2 is a good prognostic factor in CRC. We investigated the relation in terms of overall survival, disease free survival/recurrent free survival, number of patients, nations, therapy methods, pathological grade.