Published online Feb 21, 2015. doi: 10.3748/wjg.v21.i7.2191
Peer-review started: July 13, 2014
First decision: August 15, 2014
Revised: October 27, 2014
Accepted: November 7, 2014
Article in press: November 11, 2014
Published online: February 21, 2015
Processing time: 213 Days and 4.9 Hours
AIM: To investigate semaphorin 4D (Sema4D) and hypoxia-inducible factor-1α (HIF-1α) expression in colorectal carcinoma and evaluate their clinicopathological and prognostic significance.
METHODS: Eighty-six curatively resected colorectal carcinoma patients at different stages of disease were randomly selected from the group of patients who underwent surgery, and none of them received preoperative radiochemotherapy. Normal proximal adjacent bowel tissue, which served as an internal control, was obtained from 52 randomly selected patients. Immunohistochemistry was performed to analyze the expression of Sema4D and the tumor angiogenesis-related protein HIF-1α in normal colorectal tissues and colorectal carcinoma tissues. The relationships between the expression and clinical characters and prognosis were analyzed.
RESULTS: HIF-1α and Sema4D were positively expressed in 58% and 60% of colorectal carcinoma tissues, respectively. Significantly lower expression levels were observed in normal mucosa (8% and 12%, respectively). HIF-1α and Sema4D expression was closely correlated with histological tumor type, tumor-node-metastasis (TNM) stage, and lymphatic metastasis (P < 0.05), but not with age or tumor size (P > 0.05). HIF-1α and Sema4D protein expression was significantly correlated with prognosis of colorectal carcinoma, as determined by Spearman rank correlation analysis (r = 0.567; P < 0.01). Multivariate Cox analysis revealed that only Sema4D expression played a significant role in predicting patient prognosis (P < 0.05).
CONCLUSION: These findings suggest that HIF-1α and Sema4D expression correlates with histological tumor type, TNM stage, and lymphatic metastasis in colorectal carcinoma and that Sema4D is a prognostic indicator of colorectal carcinoma.
Core tip: Although originally identified in the context of neurodevelopment, semaphorin 4D (Sema4D) is also important in angiogenesis. Sema4D is widely expressed in several types of malignant solid tumors. However, its function and expression in colorectal carcinoma are not understood. This study indicates that Sema4D expression is positively correlated with HIF-1α in colorectal carcinoma and that Sema4D is a novel indicator of poor prognosis for colorectal carcinoma patients. We expect that Sema4D could be used as a reliable tool to the early and accurate prediction of tumor recurrence, and it represents a potential therapeutic target for colorectal cancer patients.