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Background: Hereditary breast and ovarian cancer (HBOC) is an autosomal dominant inherited cancer susceptibility disorder. Both BRCA1 and BRCA2 genes are considered as high penetrance genes of this syndrome. The identification of BRCA1/2 genetic alterations before cancer development, grant patients the chance to benefit from various medical cancer prevention approaches. Therefore, the appearance of recent advanced technologies in molecular analysis such as next generation sequencing has simplified full BRCA1/2 analysis. Many attempts took place in hope of understanding the molecular germline spectrum of these two genes in Moroccan HBOC patients. However, most of the past projects focused only on young breast cancer cases, lacked ovarian cancer cases in their cohort and only a limited number of these studies were able to analyze the entire exons or copy number variations for both genes. In attempt of gaining more information regarding the molecular profile of BRCA1/2 in HBOC, we conducted a study in which we analyze their molecular profile on selected Moroccan patients suspected of having HBOC syndrome.Methods: In this study we obtained blood samples from 64 selected Moroccan patients, who suffered from Breast and/or ovarian cancer and had a strong family history for cancer. To analyze BRCA1/2 punctual variants and copy number variations, we used the Ion Personal Genome Machine (PGM) and Oncomine BRCA1/2 research assay panel. Afterward, we correlated the molecular results with the clinic-pathologic data using IBM SPSS Statistics ver 2.Results: From the 64 selected cases, Forty-six had breast cancer, fifteen had ovarian cancer and three had both breast and ovarian cancer. The molecular analysis revealed that 18 patients from the 64 harbored a pathogenic variant (28%). Twelve had six different BRCA1 pathogenic variants and six had six different BRCA2 pathogenic variants. In this study, we report four pathogenic variants that to the best of our knowledge has never been reported in the Moroccan population before. Regarding copy number variation analysis, No CNV was detected in both genes for all the 64 successfully sequenced and analyzed patients in our cohort.Conclusion: Work like the present has an important implication on public health and science. It is critical that molecular profiling studies are performed on underserved and understudied population like Morocco. [ABSTRACT FROM AUTHOR]

Background: Triple Negative Breast Cancer (TNBC) is an aggressive form of breast cancer, that represents 10-20% of all breast carcinomas and characterized by the lack of a specific cell surface marker compared to other breast cancer subtypes. Due to the absence of molecular markers for TNBC his treatment options remains limited, without proven targeted therapies, which emphasize the need for discovering molecular markers that could be targeted for patient treatment, An important number of TNBC cases harbor aberrations in the phosphoinositide 3-kinase (PI3K) pathway, leading to constitutive activation of the downstream signaling pathway. Among mechanisms of PI3K enhancement, PIK3CA mutations are most frequently (~ 30%) observed, along with protein loss of PTEN and AKT activation by phosphorylation (pAkt). Therefore, we propose to analyze clinocopathologic and molecular characteristics of PI3K/AKT/PTEN pathway in Moroccan triple negative breast cancer patients.Methods: We conducted a retrospective study of 39 patients diagnosed with triple negative breast cancer between early 2013 and 2016. In this study, we used the Ion Personal Genome Machine (PGM) and Ion Torrent Ampliseq Cancer panel to sequence hotspot regions from PIK3CA, AKT and PTEN genes to identify genetic mutations in 39 samples of TNBC subtype from Moroccan patients and to correlate the results with clinical-pathologic data.Results: All patients were female with a median age of 46 years from (34-65). Most patients have had invasive ductal carcinoma (84.6%) and 69.2% of them were grade III SBR. Among the 39, 9 were right sided tumor patients and the remaining 30 were left-sided. Mutational analysis of PIK3CA gene was achieved in all TNBC patients. PIK3CA hotspot mutations were detected in 5/39 of TNBC (13%), in detail, among these 5 TNBC patients, one harbored mutation in exons 9 and four in exon 20.Conclusion: The PI3KCA gene is highly activated and plays a crucial role in the pathogenesis of TNBC more, therefore, may be a potential therapeutic target to improve outcomes in patients. [ABSTRACT FROM AUTHOR]

At present, breast cancer is the most common type of cancer in females. The majority of cases are sporadic, but 5-10% are due to an inherited predisposition to develop breast and ovarian cancers, which are transmitted as an autosomal dominant form with incomplete penetrance. The beneficial effects of clinical genetic testing, including next generation sequencing (NGS) for BRCA1/2 mutations, is major; in particular, it benefits the care of patients and the counseling of relatives that are at risk of breast cancer, in order to reduce breast cancer mortality. BRCA genetic testing was performed in 15 patients with breast cancer and a family with positivity for the heterozygous c.6428C>A mutation of the BRCA2 gene. Informed consent was obtained from all the subjects. Genomic DNAs were extracted and the NGS for genes was performed using the Ion Torrent Personal Genome Machine (PGM) with a 316 chip. The reads were aligned with the human reference HG19 genome to elucidate variants in the BRCA1 and BRCA2 genes. Mutations detected by the PGM platform were confirmed by target direct Sanger sequencing on a second patient DNA sample. In total, 4 BRCA variants were identified in 6 families by NGS. Of these, 3 mutations had been previously reported: c.2126insA of BRCA1, and c.1310_1313delAAGA and c.7235insG of BRCA2. The fourth variant, c.3453delT in BRCA1, has, to the best of our knowledge, never been previously reported. The present study is the first to apply NGS of the BRCA1 and BRCA2 genes to a Moroccan population, prompting additional investigation into local founder mutations and variant characteristics in the region. The variants with no clear clinical significance may present a diagnostic challenge when performing targeted resequencing. These results confirm that an NGS approach based on Ampliseq libraries and PGM sequencing is a highly efficient, speedy and high-throughput mutation detection method, which may be preferable in lower income countries. [ABSTRACT FROM AUTHOR]

Breast cancer is the most common cancer affecting women all over the world. The World Health Organization estimated that 1.38 million breast cancers were diagnosed worldwide in 2008. In Morocco, according to the Greater Casablanca Cancer Registry, breast cancer seems to be the first female cancer with a standardized incidence of 36.4 for an average age of 49.5 years. Germline mutations that inactivate BRCA1 and BRCA2 are responsible for breast and ovarian cancer susceptibility. The prevalence of BRCA1 and BRCA2 mutations where family history shows more than one occurrence of breast cancer under the age of 50 ranges from 8 to 21.2%. High throughput methods such as next generation sequencing are increasingly used in molecular diagnosis. Massive parallel sequencing allows the generation of millions of DNA sequences in a single run with low cost per base. Recently, next generation sequencing methods for the mutation analysis of the BRCA1 and BRCA2 genes in patients with breast and ovarian cancer have been described using both high capacity and bench top platforms. We utilized a workflow using the Ion Torrent Personal Genome Machine (IT-PGM; Life Technologies) an NGS platform, to screen germline mutations in BRCA1 and BRCA2 genes using the Ion AmpliSeq BRCA1 and BRCA2 Community Panel (Life Technologies). Till now, 16 breast cancer patients, considered being at high risk, due to medicinal examination were selected for molecular genetic testing of BRCA1 and BRCA2 genes. Mutations detected by IT-PGM platform were confirmed by traditional mutation detection assay Sanger sequencing. We show that the IT-PGM platform is sensitive and specific and can be used for routine mutational screening of patient with hereditary breast and ovarian cancers. [ABSTRACT FROM AUTHOR]