RESUMEN
Bladder cancer (BC) is the ninth most common cancer worldwide, but molecular changes are still under study. During tumor progression, Epithelial cadherin (E-cadherin) expression is altered and ß-catenin may be translocated to the nucleus, where it acts as co-transcription factor of tumor invasion associated genes. This investigation further characterizes E-cadherin and ß-catenin associated changes in BC, by combining bioinformatics, an experimental murine cell model (MB49/MB49-I) and human BC samples. In in silico studies, a DisGeNET (gene-disease associations database) analysis identified CDH1 (E-cadherin gene) as one with highest score among 130 BC related-genes. COSMIC mutation analysis revealed CDH1 low mutations rates. Compared to MB49 control BC cells, MB49-I invasive cells showed decreased E-cadherin expression, E- to P-cadherin switch, higher ß-catenin nuclear signal and lower cytoplasmic p-Ser33-ß-catenin signal, higher Ephrin-B1 ligand and EphB2 receptor expression, higher Phospho-Stat3 and Urokinase-type Plasminogen Activator (UPA), and UPA receptor expression. MB49-I cells transfected with Ephrin-B1 siRNA showed lower migratory and invasive capacity than control cells (scramble siRNA). By immunohistochemistry, orthotopic MB49-I tumors had lower E-cadherin, increased nuclear ß-catenin, lower pSer33-ß-catenin cytoplasmic signal, and higher Ephrin-B1 expression than MB49 tumors. Similar changes were found in human BC tumors, and 83% of infiltrating tumors depicted a high Ephrin-B1 stain. An association between higher Ephrin-B1 expression and higher stage and tumor grade was found. No association was found between abnormal E-cadherin signal, Ephrin-B1 expression or clinical-pathological parameter. This study thoroughly analyzed E-cadherin and associated changes in BC, and reports Ephrin-B1 as a new marker of tumor aggressiveness.
RESUMEN
Craniofrontonasal syndrome (CFNS) is a rare genetic entity with X-linked dominant inheritance. CFNS is due to mutations in the Ephrin-B1 (EFNB1) gene. It is characterized by brachycephaly, frontonasal dysplasia, palate/lip defects, dental malocclusion, short neck, split nails, syndactyly, toe and finger defects, and minor skeletal defects. Intelligence is usually unaffected. CFNS exhibits unexpected manifestations between males and females as the latter are more affected. Cellular or metabolic interference due to X inactivation explains the more severe phenotype in heterozygous females. One family with several members affected with CFNS and 100 healthy controls were examined. DNA from leukocytes was isolated to analyze the EFNB1 gene. We did molecular modeling to assess the impact of the mutation on the EFNB1-encoded protein. DNA sequencing analysis of the EFNB1 gene of the affected members showed the heterozygous missense mutation c.451G>A in the EFNB1 gene (GRcH38, chrX: 68,839,708; GERP score in hg38 of 9.961). This transition mutation resulted in the substitution of Gly at position 151 by Ser. Analysis of the healthy members of the family and 100 unrelated controls showed a normal sequence of the EFNB1 gene. Phenotypes of the patients in this family differ from the classical CFNS due to the decreased size of sulci and fissures, subarachnoid space and ventricles, and the absence of a cleft lip/palate.