Abstract :
Introduction: Mucin deregulation occurs in gastrointestinal lesions progressing to cancer. Evidences
advocate utility of mucin profile to predict malignant transformation in preneoplastic colonic lesions,
however data are controversial.
Objectives: This clinicopathological descriptive study identifies the histochemical profiles of acidic and
neutral mucins in human colonic tissues including inflammatory, non-neoplastic and neoplastic lesions.
Mucin alteration in different histological grades of adenocarcinoma is also evaluated.
Materials and Methods: After collection of relevant data, tissue samples from a cohort of 88 patients
recruited from King Abdul Aziz Specialized Hospital, Taif, Saudi Arabia were examined. Dual Alcian
Blue (AB; pH 2.5)/ Diastase (D) Periodic Acid Schiff (PAS) technique was used to differentiate acidic and
neutral mucins respectively. Statistical analysis including descriptive statistics, Pearson’s chi-square test
and linear regression was performed using SPSS.
Results: Acidic and neutral mucins were positive in 67.1 and 46.6% of lesions, respectively. All ulcerative
colitis tissues were positive for acidic mucin and 75% for neutral mucin. All non-neoplastic polyps were
positive for both mucins. Adenomatous polyps demonstrated reduced mucin but more neutral (59.3%) than
acidic one (44.4%). About 86% of adenocarcinomas revealed acidic mucin and 22.2% showed neutral
mucin with trends for acidic mucin to decrease with grade and for neutral mucin to increase with grade.
Conclusion: Altered both acidic and neutral mucin profiles occur in colonic lesions of different
pathologies. As colonic adenocarcinoma progresses from grade 1 to grade 3, acid mucin declines with
a corresponding increase in neutral mucin. Mucin profile may be of value in evaluating the preneoplastic
colorectal lesions.
Keyword :
Adenocarcinoma, Acidic mucin, Colon, Histochemistry, Neutral mucin.