SYNTHESIS OF MESSENGER-RNAS FOR TRANSFORMING GROWTH FACTOR-ALPHA AND FACTOR-BETA AND THE EPIDERMAL GROWTH-FACTOR RECEPTOR BY HUMAN-TUMORS

Abstract

Human tumors and tumor cell lines were analyzed for the presence of mRNA coding for transforming growth factors .alpha. and .beta. (TGF-.alpha. and -.beta.) and the epidermal growth factor receptor. TGF-.alpha. mRNA was not detectable in hematopoietic tumor cell lines but was found in a variety of solid tumor cells, particularly carcinomas. Many of the tumors that contained TGF-.alpha. mRNA also expressed high levels of epidermal growth factor receptor mRNA. The concentration of TGF-.alpha. in the media of several tumor cell lines did not necessarily correlate with TGF-.alpha. mRNA levels, as a substantial fraction of TGF-.alpha. can remain cell associated. The levels of TGF-.beta. mRNA in tumor cell lines and tumor specimens were variable, but higher in tumors than in the adjacent normal tissues.