High Resolution Melting Technique As an Economic Prognostic Tool for Identifying Deleterious Mutations in BRCA1, BRCA2, and P53 Genes Amongst Breast Cancer Women.

Abstract Introduction: The incidence of breast cancer (BC) has substantially increased among women younger than 50. Due to fragile economic situation in the middle east and lack of awareness, BC women are characterized by late diagnosis and thus, there is an urgent need for a cheap early prognostic tool. BC progression involves several genetic mutations via activating oncogenes or disrupting the functions of tumor suppressor genes, such as; BRCA1, BRCA2, P53. Mutation in these genes are associated with an increased risk of breast cancer and thereof, can be used as prognostic markers. High throughput technologies such as next generation sequencing (NGS) with help of different bioinformatic analysis tools give massive data about deleterious mutations in tumor suppressor genes. Therefore, in this study we aimed to establish High Resolution Melting (HRM) technique as an economic prognostic tool for identifying deleterious mutations in BRCA1/2 and P53 genes amongst familial and non-familial breast cancer patients. Patients and Methods: Forty-eight breast cancer patients (15 Familial and 33 non-familial) and 2 healthy volunteers were enrolled in the present study. Genomic DNA was extracted from breast cancer tissues and screened using NGS to identify types of mutations in both BRCA1/2 genes. All positive samples were screened for presence of mutations in BRCA 1(exon 19), BRCA2 (Exon 11F) and P53 (exon 5) using HRM. All samples were analyzed for identifying types of mutations using sanger sequencing. Results: Our results identified 57 different mutations in the three genes. Deleterious mutations are identified as follows; 13 frameshift (c.5345delA (36.3%), c.5321delC (36%), c.5337delA (27.2%)) and 8 missense mutations (c.T5320C (36.3%), c.T5330W(A/T) (27.2%)) in BRCA1 (Exon 19). 6 frameshift mutations (c.3528delA (27.2%)), 13 missense mutations (c.T3840G (72.7%), c.G3839K(G/T) (27.2%)) and 6 synonymous mutations (c.A3895R (A/G) (45.4%)) in BRCA2 (exon11F). Regarding P53 (exon 5), 10 frameshift mutations (c.813insC (63.6%)) were detected. Additionally, some of the sequences were sent to GenBank and obtained the following accession numbers; (OL512955 and OL512956 for BRCA1(Exon 19) and OL512957 for BRCA2 (Exon 11)). Moreover, mutations in the three high penetrance genes; BRCA1, BRCA2 and P53 were correlated with some clinical parameters and results showed that young age and family history were the most prominent ones. Conclusion: The present study successfully established HRM as an economic prognostic tool for identifying the presence of deleterious mutations in BRCA1/2 and P53 genes which will help correlate the presence of mutations on other affected exons when present with other risk factors as prognostic tool in BC women. STDF Acknowledgement: This project was funded by the Science and Technology Development Fund (STDF), Egypt Grant No.22944. Citation Format: Shaza Ahmed, Nasra F. Abdel Fattah, Shimaa A. Metwally, Marwa A. Abdelwahed, Hossam Taha Mohamed, Sara H. Agwa, AbdelWahab El Ghareeb, Gehan Safwat, Ahmed A. El Sherif, Mohamed M. Moneer, Samah A. Loutfy. High resolution melting technique as an economic prognostic tool for identifying deleterious mutations in BRCA1, BRCA2, and P53 genes amongst breast cancer women [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5842.