Association of BRCA1/2 Mutation and TP53 Over-Expression with Sporadic vs. Hereditary Iraqi Ovarian Cancer Patients

Aims: In Iraq, ovarian cancer is the fifth most common cause of death, and the 6th in the list of most common cancers. While TP53 is the most common tumor suppressor gene involved with human malignancies, ovarian cancer is already known to be linked to the variations in the breast cancer genes, BRCA1 and BRCA2. Herein we aim to estimate the rate of BRCA1, BRCA2 gene mutation and TP53 immuno-expression in patients with hereditary vs. sporadic ovarian cancer and to show the correlation of these biomarkers to some clinicopathological parameters.
Study Design: This is a correlational case-control study design.
Place and Duration of Study: The present study was performed in the Department of microbiology; Genetic section, College of Medicine, Babylon University. Samples taken from patients referred to general teaching hospitals and some of the private laboratories in Al-Hilla and Al-Najaf governorate, in the middle of Iraq, over a period from January 2013 to November 2013.
Methodology: Fifty-eight patients with ovarian carcinoma (30 sporadic and 28 hereditary), their ages ranging between 28-77 years, and thirty healthy women as control were included in this study. Genetic study using PCR technique was employed for BRCA1/2 gene mutation detection. Avidin-Biotin Complex (ABC) method was employed for immune-histochemical detection of Tp53 gene over-expression.
Results: BRCA1l2 gene mutation was found in 21 and 13 cases out of 28 hereditary and 30 sporadic ovarian cancer cases respectively. TP53 over-expression was detected in 18 and 17 cases out of 28 hereditary and 30 sporadic ovarian cancer cases. BRCA1l2 gene mutation and TP53 over-expression was reported more frequently in higher stage of tumor (P=0.05). The large majority of cases were diagnosed in later ages, patients with sporadic cancer got the disease later than hereditary ones.
Conclusion: BRCA1/2 and Tp53 genes alterations appears to be more important in hereditary than in sporadic ovarian cancer pathogenesis and evolution, as they are frequently associated with biologically aggressive tumors (high stages). Furthermore, TP53 gene over-expression was found to be more correlated with the cancer occurrence than BRCA1/2 mutation.