Background: The prognosis of the oral squamous cell carcinoma (OSCC) patients remains very poor, mainly due to their high propensity to invade and metastasize. E-cadherin reduced expression occurs in the primary step of oral tumour progression and gene methylation is a mode by which the expression of this protein is regulated in cancers. In this perspective, we investigated E-cadherin gene (CDH1) promoter methylation status in OSCC and its correlation with Ecadherin protein expression, clinicopathological characteristics and patient outcome. Methods: Histologically proven OSCC and paired normal mucosa were analyzed for CDH1 promoter methylation status and E-cadherin protein expression by methylation-specific polymerase chain reaction and immunohistochemistry. Colocalization of E-cadherin with epidermal growth factor (EGF) receptor (EGFR) was evidenced by confocal microscopy and by immunoprecipitation analyses. Results: This study indicated E-cadherin protein down-regulation in OSCC associated with protein delocalization from membrane to cytoplasm. Low E-cadherin expression correlated to aggressive, poorly differentiated, high grade carcinomas and low patient survival. Moreover, protein down-regulation appeared to be due to E-cadherin mRNA downregulation and CDH1 promoter hypermethylation. In an in vitro model of OSCC the treatment with EGF caused internalization and co-localization of E-cadherin with EGFR and the addition of demethylating agents increased E-cadherin expression. Conclusion: Low E-Cadherin expression is a negative prognostic factor of OSCC and is likely due to the hypermethylation of CDH1 promoter. The delocalization of E-cadherin from membrane to cytoplasm could be also due to the increased expression of EGFR in OSCC and the consequent increase of E-cadherin co-internalization with EGFR. © 2014 Bentham Science Publishers.
The role of E-cadherin down-regulation in oral cancer: CDH1 gene expression and epigenetic blockage / G., Pannone; A., Santoro; A., Feola; P., Bufo; P., Papagerakis; L., Lo Muzio; S., Staibano; F., Ionna; F., Longo; R., Franco; G., Aquino; M., Contaldo; S., De Maria; R., Serpico; A., De Rosa; C., Rubini; S., Papagerakis; A., Giovane; Tombolini, Vincenzo; A., Giordano; M., Caraglia; M., Di Domenico. - In: CURRENT CANCER DRUG TARGETS. - ISSN 1568-0096. - ELETTRONICO. - 14:2(2014), pp. 115-127. [10.2174/1568009613666131126115012]
The role of E-cadherin down-regulation in oral cancer: CDH1 gene expression and epigenetic blockage
TOMBOLINI, Vincenzo;
2014
Abstract
Background: The prognosis of the oral squamous cell carcinoma (OSCC) patients remains very poor, mainly due to their high propensity to invade and metastasize. E-cadherin reduced expression occurs in the primary step of oral tumour progression and gene methylation is a mode by which the expression of this protein is regulated in cancers. In this perspective, we investigated E-cadherin gene (CDH1) promoter methylation status in OSCC and its correlation with Ecadherin protein expression, clinicopathological characteristics and patient outcome. Methods: Histologically proven OSCC and paired normal mucosa were analyzed for CDH1 promoter methylation status and E-cadherin protein expression by methylation-specific polymerase chain reaction and immunohistochemistry. Colocalization of E-cadherin with epidermal growth factor (EGF) receptor (EGFR) was evidenced by confocal microscopy and by immunoprecipitation analyses. Results: This study indicated E-cadherin protein down-regulation in OSCC associated with protein delocalization from membrane to cytoplasm. Low E-cadherin expression correlated to aggressive, poorly differentiated, high grade carcinomas and low patient survival. Moreover, protein down-regulation appeared to be due to E-cadherin mRNA downregulation and CDH1 promoter hypermethylation. In an in vitro model of OSCC the treatment with EGF caused internalization and co-localization of E-cadherin with EGFR and the addition of demethylating agents increased E-cadherin expression. Conclusion: Low E-Cadherin expression is a negative prognostic factor of OSCC and is likely due to the hypermethylation of CDH1 promoter. The delocalization of E-cadherin from membrane to cytoplasm could be also due to the increased expression of EGFR in OSCC and the consequent increase of E-cadherin co-internalization with EGFR. © 2014 Bentham Science Publishers.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.