INCREASED EXPRESSION OF c-myc, c-erbB-2 PROTO-ONCOGENES IN HUMAN THYROID CARCINOMA / 中华内分泌代谢杂志

ABSTRACT

The expression, amplification and rearrangement of c-myc and c-erbB-2 genes in thyroid tumor were studied. 32P-dATP-labelled probes of c-myc, c-erbB-2 and v-sis DNA fragments were used to hybridise with the cellular total RNA. We found that c-myc and c-erbB-2 oncogenes were expressed in all samples. The levels of c-myc RNA were three-to eleven-fold higher in 9 out of 15 cancer samples when compared with that in normal tissues. In 7 of 15 cancer samples, c-erbB-2 gene was overexpressed 10~50 times higher than normal. No v-sis RNA was detected in all the samples. Southern blot hybridisation showed that rearrangement of c-myc oncogene were observed in 4 cancer samples, of which one showed a 150-fold amplification of c-myc gene. No amplification or rearrangement of c-erbB-2 gene was detected. These data indicate that the activat.on of c-myc and c-erbB-2 oncogenes may contribute to the development and/or maintenance of the malignant phenotype of the thyroid carcinomas.