2026-06-14T03:32:32Zhttps://repisalud.isciii.es/rest/oai/request

oai:repisalud.isciii.es:20.500.12105/74052024-11-29T20:54:16Zcom_20.500.12105_2173com_20.500.12105_2051col_20.500.12105_19597

00925njm 22002777a 4500 dc Martín-Sánchez, Esperanza author Mendaza, Saioa author Ulazia-Garmendia, Ane author Monreal-Santesteban, Iñaki author Blanco-Luquin, Idoia author Córdoba, Alicia author Vicente-García, Francisco author Pérez-Janices, Noemí author Escors, David author Megias Vazquez, Diego author López-Serra, Paula author Esteller, Manel author Illarramendi, José Juan author Guerrero-Setas, David author 2017-02-28 The CHL1 gene encodes a cell-adhesion molecule proposed as being a putative tumour-suppressor gene in breast cancer (BC). However, neither the underlying molecular mechanisms nor the clinical value of CHL1 downregulation in BC has been explored. The methylation status of three CpG sites in the CHL1 promoter was analysed by pyrosequencing in neoplastic biopsies from 142 patients with invasive BC and compared with that of non-neoplastic tissues. We found higher CHL1 methylation levels in breast tumours than in non-neoplastic tissues, either from mammoplasties or adjacent-to-tumour, which correlated with lower levels of protein expression in tumours measured by immunohistochemistry. A panel of five BC cell lines was treated with two epigenetic drugs, and restoration of CHL1 expression was observed, indicating in vitro dynamic epigenetic regulation. CHL1 was silenced by shRNA in immortalized but non-neoplastic mammary cells, and enhanced cell proliferation and migration, but not invasion, were found by real-time cell analysis. The prognostic value of CHL1 hypermethylation was assessed by the log-rank test and fitted in a Cox regression model. Importantly, CHL1 hypermethylation was very significantly associated with shorter progression-free survival in our BC patient series, independent of age and stage (p = 0.001). In conclusion, our results indicate that CHL1 is downregulated by hypermethylation and that this epigenetic alteration is an independent prognostic factor in BC. Oncotarget. 2017;8(9):15789-15801. 10.18632/oncotarget.15004 1949-2553 1949-2553 Oncotarget 28178655 http://hdl.handle.net/20.500.12105/7405 CHL1 DNA methylation breast cancer prognostic biomarker CHL1 hypermethylation as a potential biomarker of poor prognosis in breast cancer