Common multigenic activation in different human neoplasias

It was previously shown that a common multigenic component, designated as tumor-specific DNA (tsDNA), was transcriptionally active in human lymphoid neoplasias and only slightly active, if at all, in normal lymphoid cells, including the Priess cell line immortalized by Epstein-Barr virus. In the Burkitt lymphoma-derived Raji cell line, tsDNA corresponded to 2500-3000 distinct transcription units, arbitrarily defined as encoding mRNA chains of 1000 kds each. In the present study, radioactive Raji cell tsDNA was isolated by a recycling procedure which eliminates transcribed DNA sequences common to both the Raji cell and the Priess cell, and was used as a probe for homologous transcripts. The major part of this probe could be hybridized to RNAs from all the human neoplasias studied: cultured cell lines derived from leukemias, malignant lymphomas or sarcomas, leukemic cells or solid tumors (sarcomas and carcinomas) recovered from patients. In contrast, only a minor portion of Raji cell tsDNA could be hybridized to RNAs from non-malignant cells, normal human lymphoid cells or fibroblasts grown in culture, fetal and chorioplacental tissues. It is concluded that a common multigenic set is activated in a wide variety of, and perhaps in all, human neoplasias.