Next Generation Sequencing in Molecular Diagnosis of Lynch Syndrome – a Pilot Study Using New Stratification Criteria

Kašubová, Ivana; Holubeková, Veronika; Janíková, Katarína; Váňová, Barbora; Sňahničanová, Zuzana; Kalman, Michal; Plank, Lukáš; Lasabová, Zora

doi:10.14712/18059694.2018.125

Acta Medica > Archive > 2018, Vol. 61 > Issue 3 > Next Generation Sequencing in Molecular…

Acta Med. 2018, 61: 98-102

https://doi.org/10.14712/18059694.2018.125

Next Generation Sequencing in Molecular Diagnosis of Lynch Syndrome – a Pilot Study Using New Stratification Criteria

Ivana Kašubová^a, Veronika Holubeková^a, Katarína Janíková^a,b, Barbora Váňová^a,c, Zuzana Sňahničanová^a, Michal Kalman^b, Lukáš Plank^b, Zora Lasabová^a,c

^aDivision of Oncology, Biomedical Center Martin, Comenius University in Bratislava, Jessenius Faculty of Medicine in Martin, Slovakia
^bDepartment of Pathological Anatomy, Slovakia, Comenius University in Bratislava, Jessenius Faculty of Medicine University Hospital in Martin, Slovakia
^cDepartment of Molecular Biology, Comenius University in Bratislava, Jessenius Faculty of Medicine in Martin, Slovakia

Received May 15, 2018
Accepted September 10, 2018

The development of the new technologies such as the next-generation sequencing (NGS) makes more accessible the diagnosis of genetically heterogeneous diseases such as Lynch syndrome (LS). LS is one of the most common hereditary form of colorectal cancer. This autosomal dominant inherited disorder is caused by deleterious germline mutations in one of the mismatch repair (MMR) genes – MLH1, MSH2, MSH6 or PMS2, or the deletion in the EPCAM gene. These mutations eventually result in microsatellite instability (MSI), which can be easily tested in tumor tissue. According to the actual recommendations, all patients with CRC that are suspect to have LS, should be offered the MSI testing. When the MSI is positive, these patients should be recommended to genetic counseling. Here we report a pilot study about the application of NGS in the LS diagnosis in patients considered to have sporadic colorectal cancer. The inclusion criteria for the NGS testing were MSI positivity, BRAF V600E and MHL1 methylation negativity. We have used 5 gene amplicon based massive parallel sequencing on MiSeq platform. In one patient, we have identified a new pathogenic mutation in the exon 4 of the MSH6 gene that was previously not described in ClinVar, Human Gene Mutation Database, Ensembl and InSight databases. This mutation was confirmed by the Sanger method. We have shown that the implementation of new criteria for colorectal patients screening are important in clinical praxis and the NGS gene panel testing is suitable for routine laboratory settings.

Keywords

sporadic colorectal cancer, microsatellite instability, Lynch syndrome, MMR genes, next generation sequencing.

Funding

This work was supported by the Biomedical Center Martin (IMTS 26220220187), which is co-financed from EU sources, and by the projects of the Slovak Research and Development Agency no. APVV-14-0273, APVV-16-0066 and VEGA 1/0380/18.