Isolation of a new human oncogene from a diffuse B-cell lymphoma

Utilizing DNA transfection analysis with the continuous NIH 3T3 cell line as assay cell, we and other have observed that as many as 10-50% of human haematopoietic tumours contain oncogenes, the vast majority of which are members of the ras proto-oncogene family. In addition, Cooper and co-workers have reported the detection and isolation of specific oncogenes, B-lym and T-lym, which appear to be activated in human and rodent tumours of certain B and T lymphoid cells, respectively. In surveying human haematopoietic malignancies, we observed that DNA of a primary human diffuse B-cell lymphoma induced an unusual transformed focus on transfection of NIH 3T3 cells. Here, we report the molecular cloning and physical characterization of this human oncogene, whose transforming activity was shown to reside within a human DNA sequence of 45 kilobases (kb) cloned in a cosmid vector. Its properties distinguish it from previously reported retroviral or nonretroviral oncogenes.