Role of Glutathione S-Transferase M1 and Glutathione S Transferase Theta 1 Gene Polymorphism, Histopathological, and Immunohistochemistry in Carcinoma Breast.

Background: Breast cancer is the most common invasive cancer in females in developing countries such as India. It is the most common malignancy in females in the Punjab state.

Objectives: (1) The purpose of this study was to calculate the prevalence of the four subtypes of breast cancer based on molecular classification and (2) to determine the association of polymorphisms in Glutathione S-Transferase M1 (GSTM1) and Glutathione S transferase theta 1 (GSTT1) gene in carcinoma of the breast with histopathological grading.

Materials And Methods: This study analyzed histologically confirmed 100 cases of carcinoma breast; immunohistochemistry and reverse transcription polymerase chain reaction molecular tests were performed for further grading, molecular typing, and gene polymorphism.

Results: Out of 24 Grade I tumors, 18 (75.00%) expressed the GSTM1 gene and 6 (25.00%) were negative. Out of 48 Grade II tumors, 30 (62.50%) expressed the GSTM1 gene and 18 (37.50%) were negative. Out of 28 Grade III tumors, 8 (28.57%) expressed the GSTM1 gene and 20 (71.43%) were negative. Out of 24 Grade I tumors, 17 (70.83%) expressed the GSTT1 gene and 7 (29.17%) were negative. Out of 48 Grade 2 tumors, 28 (58.33%) expressed the GSTT1 gene and 20 (41.67%) were negative. Out of 28 Grade III tumors, 8 (28.57%) expressed the GSTT1 gene and 20 (71.43%) were negative.

Conclusion: Our study shows that polymorphism of both GSTM1 and GSTT1, either individually or in combination, influences the risk of developing carcinoma due to DNA damage caused by many factors including environmental and genetic.