High susceptibility of an Epstein-Barr virus-converted Burkitt's lymphoma cell line to cytotoxic drugs.

Susceptibility to cytotoxic drugs was studied using an Epstein-Barr virus (EBV) genome-negative Burkitt's lymphoma (BL) cell line (Ramos) originating from the tumor cells and an in vitro EBV-converted Ramos cell line (B7). Decreased doubling time (DT) with increased saturation density (SD) and elevated [3H]thymidine incorporation were shown in B7, indicating more rapid cell proliferation and growth. However, B7 was highly susceptible to cytotoxic drugs when compared to Ramos. These results indicated whether the presence or absence of EBV genome in tumor cells may be beneficial for evaluation of susceptibility to cytotoxic chemotherapy in patients with BL.