Title: Expression of Alpha-Methylacyl-Coenzyme A Racemase (AMACR) in Colo-Rectal Neoplasms
Authors: Dr S.A.K. Adil, Dr Neha Saroha, Dr Bharathi M
DOI: https://dx.doi.org/10.18535/jmscr/v8i2.112
Abstract
Introduction: Colorectal cancers are gaining importance globally as major cause of morbidity and mortality. AMACR is a dietary enzyme which aids in beta- oxidation of branched chain fatty acids. Hence, its expression in colorectal premalignant lesions and carcinoma suggest possible role in its carcinogenesis.
Aim: To study the expression of AMACR in colorectal neoplasms and its correlation with the histological grade.
Materials and Methods: It is a hospital based retrospective study. 30 blocks were retrieved from tissue samples previously diagnosed as colorectal neoplasms at Mysore Medical College, Mysore during a period of 2 years. AMACR expression was studied by Immunohistochemistry and correlated with histological grade. Mean, frequency and Chi-square tests were used for analysis.
Results: Out of 30 samples with colorectal tumours, 25 were malignant (83.3%) and 5 were benign (16.7%). Age of the study population ranged between 35-75 years. Most of the patients were above 45 years of age (86.6%). Females were affected equally as males representing 50% each. Histological grading revealed 21 cases of well differentiated tumours (84%), 1 case of moderately differentiated tumour (4%) and 3 cases of poorly differentiated tumour (12%). Overall, study showed positive AMACR expression in colorectal neoplasms (63%) and significant correlation between histological grade of carcinoma and AMACR expression.
Conclusion: This study showed increased expression of AMACR in colorectal carcinomas and weakly in adenomas as compared to normal colonic mucosa which suggests its possible role in colorectal carcinogenesis. Loss of AMACR immunostaining in poorly differentiated carcinomas suggests its role in tumour differentiation. AMACR can be used as possible therapeutic agent.
Keywords: Colorectal cancers, Alpha-Methylacyl-Conenzyme A Racemase (AMACR), Immunohistochemistry.
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