Resumen: Background: CDH1 and CTNNA1 remain as the main genes for hereditary gastric cancer. However, they only explain a small fraction of gastric cancer cases with suspected inherited basis. In this study, we aimed to identify new hereditary genes for early-onset gastric cancer patients (EOGC;<50 years old).
Methods: After germline exome sequencing in 20 EOGC patients and replication of relevant fndings by gene-panel sequencing in an independent cohort of 152 patients, CTNND1 stood out as an interesting candidate gene, since its protein product (p120ctn) directly interacts with E-cadherin. We proceeded with functional characterization by generating two knockout CTNND1 cellular models by gene editing and introducing the detected genetic variants using a lentiviral delivery system. We assessed β-catenin and E-cadherin levels, cell detachment, as well as E-cadherin localization and cell-to-cell interaction by spheroid modeling.
Results: Three CTNND1 germline variants [c.28_29delinsCT, p.(Ala10Leu); c.1105C>T, p.(Pro369Ser); c.1537A > G, p.(Asn513Asp)] were identifed in our EOGC cohorts. Cells encoding CTNND1 variants displayed altered E-cadherin levels and intercellular interactions. In addition, the p.(Pro369Ser) variant, located in a key region in the E-cadherin/p120ctn binding domain, showed E-cadherin mislocalization.
Conclusions: Defects in CTNND1 could be involved in germline predisposition to gastric cancer by altering E-cadherin and, consequently, cell-to-cell interactions. In the present study, CTNND1 germline variants explained 2% (3/172) of the cases, although further studies in larger external cohorts are needed. Idioma: Inglés DOI: 10.1007/s10120-024-01504-7 Año: 2024 Publicado en: Gastric Cancer 27, 4 (2024), 747-759 ISSN: 1436-3291 Financiación: info:eu-repo/grantAgreement/EC/HORIZON EUROPE/101079217/EU/TWINNING FOR A EUROPEAN CONSORTIUM OF RECTAL CANCER RESEARCH INSTITUTIONS THROUGH STEPPING UP SCIENTIFIC, TECHNOLOGICAL AND INNOVATION EXCELLENCE OF IORS/STEPUPIORS Financiación: info:eu-repo/grantAgreement/ES/ISCIII/PI16-00599 Financiación: info:eu-repo/grantAgreement/ES/ISCIII/PI20-00113 Financiación: info:eu-repo/grantAgreement/ES/ISCIII/PI21-00333 Financiación: info:eu-repo/grantAgreement/ES/ISCIII/PI22-00537 Tipo y forma: Artículo (Versión definitiva) Área (Departamento): Area Medicina (Dpto. Medicina, Psiqu. y Derm.)