Protein Tyrosine Kinase Activity in Human Thyroid Papillary Carcinoma

Abstract

We compared the protein tyrosine kinase (PTK) activity in the acytosolic and particulate fractions of homogenates obtained from 10 papillary thyroid adenocarcinomas with the corresponding activity in 10 specimens from adjacent normal thyroid tissue and 8 follicular adenomas. The cytosolic PTK activity of papillary adenocarcinomas was significantly elevated compared to normal and adenoma tissue. The particulate PTK activity was also significantly elevated in the papillary adenocarcinomas. The cellular distribution of PTK activity (cytosolic activity in percentage) in normal thyroid tissue, adenomas, and papillary adenocarcinomas showed no significant difference (62%0, 64% and 63% respectively). These findings indicate that elevated cytosolic PTK activity may be a potentially useful marker for papillary thyroid carcinoma.