Synergistic antitumor effect of glycosylated recombinant human lymphotoxin with human interferon-gamma on lymphotoxin-sensitive human tumor

Polymorphism in the genes of alpha and beta tumor necrosis factors (TNF-alpha and TNF-beta) and gamma interferon (IFN-gamma) among Iranian women with breast cancer

The association of the polymorphism in the genes of TNF-alpha, TNF-beta and IFN-gamma with breast cancer was investigated in the present study. There were no differences in the TNF-alpha and TNF-beta alleles and genotypes frequencies between breast cancer patients (n=223) and control subjects (n=267). The correlations between TNFA or TNFB alleles or genotypes and clinicopathological indices were also insignificant. However, the frequency of IFN-gamma+874 T/T genotype was significantly higher in breast cancer patients compared to those of controls (P<0.002; OR=2.03, 95% CI=1.28-3.2) which indicates that Iranian women carrying the IFN-gamma+874 T/T genotype may be exposed to an increased risk of breast cancer development.

Tumour growth inhibition in mice by glycosylated recombinant human lymphotoxin: analysis of tumour-regional mononuclear cells involved with its action

We compared the antitumour effects of glycosylated LT (gLT), nonglycosylated LT and TNF against a solid tumour in mice. We found that: (a) The systemic administration of gLT showed significant antitumour activity. These effects were, however, quite small in nude mice. Nonglycosylated LT and TNF attained the same degree of effectiveness as gLT, but at a 5-times higher dose. The serum half-life of gLT was 3-fold longer than that of nonglycosylated LT and 22-fold longer than that of TNF. (b) The effect of gLT was significantly blocked by pretreatment with anti-asialo GM1 antibody. Treatment with gLT produced a significant reduction in numbers of tumour-regional mononuclear cells, which in turn, produced increases intensive necrosis. (c) Mononuclear cells in the tumour tissues before gLT-injection were predominantly IL-2 receptor +/CD3- cells and CD3+ cells. Pretreatment with the anti-asialo GM1 antibody produced a drastic reduction of IL-2 receptor +/CD3- cells. These findings suggest that the efficient antitumour effect of gLT is due to a longer serum half-life than that of nonglycosylated LT or TNF in vivo, and its function is largely mediated by IL-2 receptor +/CD3- cells.