Necessity of biotherapeutic treatments inducing TH1 cell functions in colorectal cancer

Abstract

Our previous data on colorectal cancer suggest that there are faults at the level of mechanisms of the proliferative responses of patients peripheral blood mononuclear cells (PBMC) to the interleukin (IL)-2 and IL-2 PBMC production, which increase with the stage advancement. The damages in the proliferative response seem to be eliminated by the costimulator effects of the signals produced by the anti-CD3 monoclonal antibody (antiCD3), and the disregulation in TH subsets of CD4+ T cells with a malfunction of TH1 cells and an expansion of TH2, might contribute to this situation. So, by using biotherapeutic treatments to allow the generation of productive immune response in these patients it is essential to identify the defect in their immune system to discover how these mechanisms should be appropriately manipulated in vivo to switch their immune response from a non-productive to a productive one. We have studied this in a group of patients and healthy subjects as the control group, performing their immunological evaluation by determining these parameters: serum levels of IL-2, interferon (IFN) gamma, IL-4, IL-6, IL-7, IL-8, tumour necrosis factor (TNF) alpha, soluble IL-2 receptor (sIL-2R), intercellular adhesion molecule 1 (sICAM-1) and CD30 (sCD30) molecules; PBMC phenotypic antigens expression (CD3, CD4, CD8, CD19, CD16, CD56, CD57, CD25) on peripheral blood mononuclear cells (PBMC); proliferative response of PBMC to IL-2, IL-4 and anti-CD3 monoclonal antibody (antiCD3). Moreover, since mutant c-Ki-ras oncogene is a very frequent finding in colorectal cancers and there are indications which suggest its involvement in tumour progression, the analysis of c-ki-ras codon 12 and 13 were determined and the statistical evaluation of the above immunological parameters were performed by comparing the patient groups with (M+) and without (M-) these mutations with each other, and with the healthy group. The results underline the necessity of biotherapeutic treatments inducing TH1 cell functions in these patients. Moreover in M+ it seems also important to solve the problem of the switch from B to macrophage cells as immune cells which present antigens, and the possible involvement of c-Ki-ras gene mutations in the impairment of T cell receptor activation (TCR).