Abstract:
Expression of the E-cadherin/β-catenin complex in oral squamous cell carcinoma and its
correlation with histomorphology and metastasis.
The immunohistochemical expression of E-cadherin and β-catenin was examined in 30
primary oral squamous cell carcinomas in patients with (n=19) and without (n=11) nodal
metastasis, as confirmed on histopathological examination of the resected regional lymph
nodes. The corresponding primary and nodal metastases tissue samples were available for 17
patients. The 30 primary carcinomas were histologically graded according to the invasive
tumour front grading system and by conventional Broders’ criteria. None of the 30 primary
carcinomas showed homogenous, membranous E-cadherin and β-catenin expression when
compared to the normal oral squamous epithelium. Staining was heterogeneous in 73%
(22/30) and in 77% (23/30) of the primary carcinomas stained for E-cadherin and β-catenin
respectively. There was a highly significant reduction (P<0,001) of both E-cadherin and β-
catenin expression with progression from the well-differentiated areas to the less
differentiated tumour cells at the invasive tumour front. At the invasive tumour front,
however, irrespective of the nodal status and invasive tumour front grading score, 28/30
(93%) tumours showed loss of E-cadherin expression. Loss of β-catenin expression was
recorded in 22/30 (73%) cases.
These findings indicate that E-cadherin and β-catenin play a key role in the loss of
differentiation of tumour cells in oral squamous cell carcinoma and while they may be
permissive for metastasis, in isolation, E-cadherin and β-catenin are probably not predictive
of metastatic potential in oral squamous cell carcinoma.
