LAPTM4B GENE EXPRESSION AND POLYMORPHISM AS DIAGNOSTIC MARKERS OF BREAST CANCER IN EGYPTIAN PATIENTS

Background: The aim of this study was to investigate the association between LAPTM4B gene polymorphism and the risk of breast cancer among Egyptian female patients. Also, measurement was done of its serum level to evaluate its significance as a diagnostic marker for breast cancer. Methods: This case control study was done on 88 breast cancer patients, 40 with fibroadenoma and 80 healthy subjects. Genotyping of the LAPTM4B polymorphism was determined by PCR. Serum LAPTM4B level was measured using ELISA. Results: There was a significant difference in the (*1/2+*2/2) genotypes in breast cancer patients (59.1) compared to the control subjects (43.8%) (P=0.047; OR=1.86; 95% CI=1.01-3.43). The frequency of the allele 2* of the LAPTM4B gene was significantly higher in breast cancer patients (36.4%) than in the control (25.6%) (p=0.034; OR=1.66; 95% CI=1.04-2.65). Genotypes (*1/2+*2/2) were significantly associated with the differential classification of TNM. Serum level of LAPTM4B was significantly higher in breast cancer patients than in control and fibroadenoma and in fibroadenoma patients than in control. In breast cancer patients, serum LAPTM4B was significantly higher in stage III and in large tumor size. Serum LAPTM4B was significantly higher in the cancer patients' genotypes (*1/2+*2/2). Conclusions: Genetic polymorphism of LAPTM4B is a potential risk factor for the development of breast cancer. Serum LAPTM4B may be used as a diagnostic and prognostic marker for breast cancer.