A test for foetal gene expression at the level of transcription in hepatoms

The presence of a variety of embryonic and foetal gene products in neoplasms is well documented. Two such products, i.e. carcinoembryonic antigen and alpha foetoprotein, are currently being used for clinical diagnosis and the assessment of prognosis. The purpose of this study has been to examine the possibility of the reactivation of a foetal gene associated with foetal liver in the Morris 5123C hepatoma and host liver after prolonged tumour bearing. The foetal gene for globin was chosen for study as production of foetal globin in cancer patients has been observed and the technique for quantiation of globin messenger RNA is available. The quantitation of globin mRNA permits the identification of a gene product which is not related to the tissue of origin of the tumor being studied and which is influenced by pre-translational control mechanisms only. The influence of tumour bearing on foetal globin gene expression by the host liver is also reported. We report molecular hybridization studies of total nucleic acid extracts from foetal, 2-day neonatal, adult and host liver and the Morris 5123C transplantable hepatoma with a complementary DNA copy of globin messenger RNA. The results indicate that there is no activation of the foetal globin gene in these tissues in spite of erythrocytosis in the host animal.