Induction of chromosomal rearrangement by tumor necrosis factors produced by primary B lymphoblastoid cells derived from cancer patients

We have previously reported the isolation of the cytotoxic factors, tumor necrosis factor-α (TNF-α), from monocytes and lymphotoxin or TNF-β, from an established human B lymphoblastoid cell line. In the current study, we examined the production of cytotoxic factors by primary lymphoid cells derived from patients with different malignancies and correlated it with the chromosomal abnormalities in producer cells. Lymphoid cell lines were established from 78 untreated patients with breast carcinoma, 2 with cervical carcinoma, 24 with colon carcinoma, 12 with prostate carcinoma, 3 with melanoma, and the remaining from asymptomatic family members. Lymphoid cells from all 119 patients and their asymptomatic family members constitutively produced as much as 240 units/ml of TNF-β in vitro. In contrast, TNF-α was produced by lymphoid cells from only 6 patients; a related cytokine with similar biological properties to TNF-β. Sixty-five of these 119 samples were also analyzed for chromosomal abnormalities by standard cytogenetic technique. The production of TNFs was accompanied with varying degrees of chromosomal abnormalities in the cells from all patients. These included both structural and numerical abnormalities. We also examined the direct effect of TNF-β on the induction of chromosomal abnormalities in growing cultures of both T and B lymphocytes. Our preliminary results indicate that treatment of lymphocytes with this cytokine induced chromosomal rearrangements in a dose- dependent manner. Thus, we provide for the first time both indirect and direct evidence that a soluble mediator such as TNF-β can induce chromosomal alterations commonly associated with different types of tumors.