Copyright
©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
Evaluation of clinical significance of claudin 7 and construction of prognostic grading system for stage II colorectal cancer
Ji-Chuan Quan, Jian Peng, Xu Guan, Zheng Liu, Zheng Jiang, Hai-Peng Chen, Meng Zhuang, Song Wang, Peng Sun, Hong-Ying Wang, Shuang-Mei Zou, Xi-Shan Wang
Ji-Chuan Quan, Xu Guan, Zheng Liu, Zheng Jiang, Hai-Peng Chen, Meng Zhuang, Xi-Shan Wang, Department of Colorectal Surgery, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
Jian Peng, Hong-Ying Wang, State Key Laboratory of Molecular Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
Song Wang, Peng Sun, Department of Colorectal Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin 150081, Heilongjiang Province, China
Shuang-Mei Zou, Department of Pathology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100021, China
Author contributions: Quan JC wrote the manuscript; Wang HY, Zou SM and Wang XS conceived of and designed the study and contributed equally; Guan X, Zhuang M, Wang S, Chen HP, Liu Z and Sun P collected the data; Quan JC, Peng J and Jiang Z analyzed the data; all authors made critical revisions for the manuscript and approved the final version.
Supported by the Beijing Science and Technology Program, No. D171100002617004.
Institutional review board statement: This study was reviewed and approved by the Ethics Committee of the Cancer Hospital, Chinese Academy of Medical Sciences, Beijing, China.
Informed consent statement: Patients were not required to give informed consent to the study because the analysis used anonymous clinical data that were obtained after each patient agreed to treatment by written consent.
Conflict-of-interest statement: All authors declare no conflicts-of-interest related to this article.
Data sharing statement: No additional data are available.
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: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Xi-Shan Wang, MD, Professor, Department of Colorectal Surgery, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 17 Panjiayuan Nanli, Chaoyang District, Beijing 100021, China. wangxsh@126.com
Received: April 5, 2020
Peer-review started: April 5, 2020
First decision: April 22, 2020
Revised: April 27, 2020
Accepted: May 19, 2020
Article in press: May 19, 2020
Published online: June 6, 2020
BACKGROUND
Claudin 7 is often abnormally expressed in cancers and promotes the progression of some malignancies. However, the role of claudin 7 in stage II colorectal cancer (CRC) has not been studied.
AIM
To assess the expression and prognostic value of claudin 7 in stage II CRC.
METHODS
We retrospectively studied 231 stage II CRC patients who underwent radical surgery at our hospital from 2013 to 2014. The protein expression level of claudin 7 was assessed and its relationship with clinicopathological features and prognosis was statistically analyzed. The independent prognostic factors were identified by Cox proportional hazards models. A prognostic grading system was constructed to stratify the survival of CRC patients.
RESULTS
The expression of claudin 7 was significantly reduced in cancer tissues compared with normal tissues (P < 0.001), and its low expression was closely related to recurrence of the disease (P = 0.017). Multivariate analysis confirmed that claudin 7 low expression (claudin 7-low) (P = 0.028) and perineural invasion positivity (PNI+) (P = 0.026) were independent predictors of poor disease-free survival (DFS). A prognostic grading system based on the status of claudin 7 and PNI classified the patients into three prognostic grades: grade A (claudin 7-high and PNI-), grade B (claudin 7-low and PNI-, claudin 7-high and PNI+), and grade C (claudin 7-low and PNI+). The DFS was significantly different among the three grades (grade B vs grade A, P = 0.032; grade C vs grade A, P < 0.001; grade C vs grade B, P = 0.040).
CONCLUSION
Claudin 7 can be used as a new prognostic marker to predict the DFS of patients with stage II CRC. The prognostic grading system with the addition of claudin 7 can further improve prognosis stratification of patients.
Core tip: The clinical significance of claudin 7 in stage II colorectal cancer has not been studied. This is believed to be the first study to assess the expression and prognosis of claudin 7 in stage II colorectal cancer. We found that claudin 7 and perineural invasion were independent prognostic factors associated with disease-free survival. A prognostic grading system was constructed based on the status of claudin 7 and perineural invasion, which can better stratify disease-free survival.
