EXPRESSION OF RAS P21 IN BENIGN AND MALIGNANT THYROID LESIONS

It is now widely accepted that human neoplasms arise as a result of a sequence of mutations affecting the structure of genes involved in gro wth control. Identifying the nature of such genetic mutations in thyro id neoplasms and their prevalence in the various tumor phenotypes is c ritical to the understanding of their pathogenesis. Mutational activat ion of ras oncogenes has been associated with human thyroid neoplasia. We examined the expression of ras oncogene in benign hyperplastic or inflamatory lesions of the goiter, as well as in benign and malignant thyroid tumors. Although no significant differences of ras oncogene ex pression was found between benign and malignant lesions, the overexpre ssion in proliferative areas generally suggests the possible involveme nt of ras oncogene in the trophic hormone control of the thyroid.