Immunocytochemically detectable TGF-beta associated with malignancy in thyroid epithelial neoplasia.
The possible role of changes in TGF-beta expression in the multistage development of thyroid cancer was assessed. The presence of TGF-beta 1 in thyroid epithelial cells was analyzed in sections of normal and tumor tissue using an immunoperoxidase technique employing an antibody directed against the amino-terminal 30 amino acids of mature TGF-beta 1. Specific immunostaining was clearly detected in epithelial cells in 58% of malignant thyroid tumours (including follicular, papillary, and anaplastic variants). However, no positive cells were seen in any of 7 benign tumors nor in any normal thyroid epithelium. Within the cancer group as a whole, there was no significant correlation with pathological grade or clinical stage of tumor but in one subgroup--follicular carcinomas--a significant association was noted between TGF-beta immunostaining and the presence of a specific mutation of the H-ras oncogene (codon 61, gln----arg). We conclude that a major alteration in expression of TGF-beta occurs specifically in the malignant stage of tumor development in thyroid follicular epithelium and speculate on its possible role in this process.
Jasani
B
B
Department of Pathology, University of Wales College of Medicine, Cardiff, United Kingdom.
Wyllie
F S
FS
Wright
P A
PA
Lemoine
N R
NR
Williams
E D
ED
Wynford-Thomas
D
D
D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism; D000236:Adenoma / Q000235:genetics / Q000378:metabolism; D002291:Carcinoma, Papillary / Q000235:genetics / Q000378:metabolism; D011905:Genes, ras; D006801:Humans; D007150:Immunohistochemistry; D009154:Mutation; D013961:Thyroid Gland / Q000378:metabolism; D013964:Thyroid Neoplasms / Q000235:genetics / Q000378:metabolism*; D015291:Transforming Growth Factors / Q000378:metabolism*
D015291:Transforming Growth Factors