2 research outputs found
High expression of claudin-1 protein in papillary thyroid tumor and its regional lymph node metastasis
Claudins, known as major contributors in the
formation of the tight junction, are differentially expressed
in malignant tumors as compared to the corresponding
healthy tissues. Therefore, they are thought to play a role in
carcinogenesis and tumor progression. Altered expression
of claudin-1 has been reported in several tumor types
including endometrial, papillary renal cell and colonic
carcinoma, and increased claudin-1 mRNA levels have
been observed in papillary thyroid carcinoma (PTC). In this
study, we aimed at determining the pattern of claudin-1
expression in various types of thyroid lesions at the protein
level and investigating the immunolocalization of β-catenin
reported to regulate claudin-1 expression. Samples included
19 PTCs, ten cases of corresponding regional lymph node
metastasis, eight papillary microcarcinomas (PMC), 17
follicular thyroid carcinomas (FTC) and 19 follicular
adenomas (FA). All cases were evaluated by quantitative
immunohistochemistry. Conspicuous claudin-1 immunostaining
was detected in the majority of PTC/PMC primary
tumors and lymph node metastases (19/27 and 9/10,
respectively). On the other hand, we found weak or no
claudin-1 expression in any of the FA and FTC cases or
peritumoral non-malignant thyroid tissues. Our data prove
that high claudin-1 protein expression is specific for PTC
and its regional lymph node metastases, while we failed to
verify that claudin-1 is regulated by β-catenin in thyroid
tumors. Based on these results