Reduction of E-cadherin expression is associated with non-lobular breast carcinomas of basal-like and triple negative phenotype.
OBJECTIVE
E-cadherin inactivation in breast cancer has been shown to be strongly associated with lobular breast cancer. However, little is known about the levels of E-cadherin expression according to the breast cancer "molecular" subtypes. The aim of this study was to address the distribution of E-cadherin expression according to the different molecular subtypes of breast cancer.


METHODS
E-cadherin expression was immunohistochemically analysed in a tissue microarray containing duplicate cores of 245 invasive breast carcinomas, of which 182 cases were of non-lobular histology, using a semi-quantitative scoring system based on the percentage of cells showing membrane immunopositivity.


RESULTS
In non-lobular breast carcinomas, reduced and/or negative E-cadherin expression was significantly associated with lack of oestrogen receptor expression, low levels of CCND1 expression, positivity for cytokeratins 5/6 and 17, epidermal growth factor receptor and caveolins 1 and 2, p53 expression, high MIB-1 proliferation indices, basal-like phenotype and triple negative phenotype.


CONCLUSIONS
This study demonstrates that in the group of non-lobular breast cancers, reduction/lack of E-cadherin expression is preferentially found in basal-like breast carcinomas.
D014408:Biomarkers, Tumor / Q000378:metabolism*; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D015820:Cadherins / Q000378:metabolism*; D018270:Carcinoma, Ductal, Breast / Q000378:metabolism / Q000473:pathology; D018275:Carcinoma, Lobular / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D009361:Neoplasm Invasiveness; D009363:Neoplasm Proteins / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D010641:Phenotype; D011379:Prognosis; D016019:Survival Analysis
D014408:Biomarkers, Tumor; D015820:Cadherins; D009363:Neoplasm Proteins