Preliminary study of BRCA1 and BRCA2 mutations among Vietnamese ovarian carcinomas population by using ion personal genome machine platforms

Abstract

BRCA1 and BRCA2 are two important tumor suppressor genes. The germline and somatic mutations of these two genes in ovarian carcinomas are sensitive for treatment with ADP-ribose polymerase enzyme inhibitor (PARPi). Recently, several PARPi drugs, such as Olaparib and Rucaparib, have been approved for ovarian cancer with BRCA1/2 germline mutations by Food and Drug Administration (FDA), and for both germline and somatic mutations by European Medicines Agency (EMA). However, there have no been reliable data about the prevalence of mutations of these two genes in ovarian carcinomas population for treatment in Vietnam so far. Therefore, we studied the prevalence of the BRCA1/2 germline and somatic mutations among ovarian carcinomas patients in the Vietnamese population. In this study, we sequenced these two genes by using Ion Torrent PGM. The subjects of the study are 11 formalin-fixed paraffin-embedded tumor (FFPE) samples from 11 patients with ovarian carcinomas obtained from Tu Du Hospital of Obstetrics and Gynecology (Vietnam). Multiplex PCR then was performed on the DNA samples and two controls containing known mutations by using Oncomine BRCA Research Assay. Of the sequenced 11 samples, a pathogenic mutation (1/11 patient, 9.1%) detected on the BRCA1 gene was a nonsense point mutation causing stop codon at the position of amino acid 1772. Consequently, our sequencing workflow shows the success in identifying and investigating the prevalence of BRCA1/2 mutation in a small group of ovarian carcinomas with FFPE tumor samples.