Brief Article
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World J Gastroenterol. Aug 28, 2010; 16(32): 4089-4094
Published online Aug 28, 2010. doi: 10.3748/wjg.v16.i32.4089
Altered expression of MUC2 and MUC5AC in progression of colorectal carcinoma
Xiao-Dong Bu, Nan Li, Xiao-Qiang Tian, Li Li, Jin-Song Wang, Xiao-Jin Yu, Pei-Lin Huang
Xiao-Dong Bu, Nan Li, Xiao-Qiang Tian, Pei-Lin Huang, Department of Pathology, School of Medicine, Southeast University, Nanjing 210009, Jiangsu Province, China
Li Li, Jin-Song Wang, Department of Pathology, Nanjing First Hospital of Nanjing Medical University, Nanjing 210006, Jiangsu Province, China
Xiao-Jin Yu, Department of Epidemiology and Statistics, School of Public Health, Southeast University, Nanjing 210009, Jiangsu Province, China
Author contributions: Bu XD, Li N and Tian XQ contributed equally to this work and performed the majority of experiments; Li L and Wang JS collected the tissue samples and performed the diagnoses; Yu XJ performed the statistical analysis; Bu XD and Huang PL designed the study and wrote the manuscript.
Correspondence to: Pei-Lin Huang, Professor, Department of Pathology, School of Medicine, Southeast University, Nanjing 210009, Jiangsu Province, China. hplwpp@yahoo.cn
Telephone: +86-25-83792919 Fax: +86-25-83792076
Received: April 7, 2010
Revised: May 27, 2010
Accepted: June 4, 2010
Published online: August 28, 2010
Abstract

AIM: To study the expression profiles of MUC2 and MUC5AC in tumorigenesis of colorectal carcinoma and in its different pathologic types.

METHODS: Formalin-fixed, paraffin-embedded human colorectal tissue specimens were immunostained with antibodies against MUC2 and MUC5AC. Six samples of normal mucosa (NM), 12 samples of hyperplastic polyp (HP), 15 samples of tubular adenoma with low-grade dysplasia (LGD), 14 samples of tubular adenoma with high-grade dysplasia (HGD), 26 samples of conventional colorectal adenocarcinoma (CCA), 15 samples of mucinous carcinoma (MC), and 8 samples of signet-ring cell carcinoma (SRCC) were collected.

RESULTS: MUC2 was the most widely expressed protein in each study group, although the number of MUC2-positive cases was less in CCA group than in other groups (P < 0.05). The staining score for MUC2 was significantly decreased in the HP-LGD-HGD-CCA sequence (r = -0.73436, P < 0.0001). Among the neoplasms, MC and SRCC were more frequently associated with the high expression of MUC2 (P < 0.05) than with that of CCA. MUC5AC expression was detected in all groups but not in NM group. Furthermore, the staining score for MUC5AC was higher in HP, LGD, HGD, MC and SRCC groups than in NM and CCA groups (P < 0.05). The frequency of simultaneous expression of MUC proteins was significantly higher in MC and SRCC groups than in CCA group (P < 0.05).

CONCLUSION: Alterations in MUC expression occur during colorectal tumorigenesis. The transformation process in MC and SRCC may be different from that in the traditional adenoma-carcinoma sequence.

Keywords: Colorectum, Tumorigenesis, MUC2, MUC5AC, Immunohistochemistry