HRAS and neoplasm: To determine whether it can detect the oncogenic activity of cellular DNA derived from four human tumor-cell lines (HeLa, A549, HT-1080, and CEM), DNA (100 μg) was inoculated into newborn CD3 epsilon mice both in the presence of 1 μg of linear pMSV-T24-H-ras/MSV-c-myc as positive control and in its absence.