Frequency of the phosphatidylinositol3-kinase, catalytic, α-polypeptide gene amplification in ovarian cancer among Sudanese women: a cross-sectional study

Background: Phosphatidylinositol3-kinase, catalytic, α-polypeptide (PIK3CA) gene is frequently amplified in ovarian carcinoma (OC). To the best of our knowledge, there is a dearth of published reports about the amplification of the PIK3CA gene among Sudanese women with OC. This study aimed to detect the amplification of the PIK3CA gene and its relationship with clinicopathological variables among Sudanese women with OC. Methods: This cross-sectional study included 90 ovarian cases: 83 cases of women diagnosed with OC at Omdurman Maternity Hospital in the period 2013-2018; 7 cases of women with normal ovarian tissues were used as a control to normalize the results. Formalin-fixed paraffin-embedded tissue sections (FFPE) were used to extract RNA at the Institute of Endemic Diseases, Sudan. PIK3CA gene amplification was assessed using quantitative real-time PCR. Results: Amplification of PIK3CA was observed in 33.7% (n = 28/83) of women, with a high frequency in women with clear cell (66.7%; n = 4/6), undifferentiated (50.0%; n = 1/2), serous (35.5%; n = 11/31), mucinous (33.3%; n = 4/12),other (30.8%; n = 4/13), and endometrioid (21.1%; n = 4/19) carcinomas. High frequency was seen in women with higher (39.5%; n = 17/43) rather than in lower grade carcinomas (27.5%; n = 11/40), and in older (43.4%; n = 11/32) rather than younger (30.0%; n = 12/40) women. No significant association between PIK3CA amplification and tumor histologic type, grade, and age of women was observed (Fisher’s Exact test: p = 0.660, 0.698 and 0.687, respectively). Conclusion: PIK3CA gene amplification occurs in about one third of Sudanese women with OC, more frequently in high tumor grades and older women, but not to a statistically significant level. These findings support previous studies suggesting that oncogenic PIK3CA has an essential role in OC progression and may offer a strategy for exact targeted therapy and prognostic evaluation