Role of cell growth factor (interleukin-2) and its receptors in carcinoma cervix patients

Effect of blood transfusion during radiotherapy on the immune function of patients with cancer of the uterine cervix: role of interleukin-10

PURPOSE

To analyze prospectively the effects of blood transfusion administered during radiotherapy (RT) on the immune function of patients with locally advanced cervical cancer.

METHODS AND MATERIALS

In a total of 15 patients, 7 transfused and 8 untransfused, lymphocyte populations, including CD3+, CD4+, and CD8+ T-cell subsets, B cells (CD19+), and natural killer (NK) cells (CD56+, CD16+, CD3-) were studied before (i.e., time 0), during (i.e., times 1 and 2), and after (i.e., time 3) therapy. Expression of the early (CD25) and late (HLA-DR) activation markers on CD3+ T cells, the intracellular levels of perforin in CD8+ and CD56+ cells, and interferon (IFN)-gamma, interleukin (IL)-2, and IL-4 in CD4+ and CD8+ T cells were also measured. NK cell cytotoxicity against the NK-sensitive target K-562 cells and CD8+ T-cell-directed cytotoxicity against OKT3 hybridoma cells were also assessed. Finally, the plasma levels of the immunoregulatory cytokine IL-10 were analyzed by enzyme-linked immunosorbent assay.

RESULTS

The mean absolute number of all lymphocyte subsets compared with pretreatment levels decreased significantly during RT of both transfused and untransfused patients (p >0.001), with no detectable differences between the two groups in terms of total lymphocytes or relative numbers of CD3+ and CD4+ T cells, CD56+ NK cells, or CD19+ B cells. In contrast, concomitant with an inversion of the CD4/CD8 ratio, a significant increase in the number of CD8+ T cells at time 2 and CD3+ T cells, CD8+ T cells, and NK cells at time 3 was found in the transfused patients compared with the untransfused group. The percentages of CD25+/CD3+ T cells and HLA-DR+/CD3+ T cells increased during RT of the untransfused patients, but CD3+ T cells showed decreased CD25 expression and increased HLA-DR expression in the transfused group. An increase of CD8+ IFN-gamma+ T cells with a concomitant decrease in CD8+ IL-2+ T cells was found in the transfused vs. untransfused group, and no differences were noted in the percentage of CD4+ IFN-gamma+ T cells and CD4+ IL-2+ T cells. The proportion of perforin-positive CD8+ and CD56+ cells was higher in the transfused group than in the untransfused group. However, CD56+ cells and CD8+ T cells from the transfused patients showed markedly diminished cytotoxic function. Finally, IL-10 was detected only in the plasma of the transfused patients.

CONCLUSION

Blood transfusion during primary RT for cervical cancer profoundly alters the magnitude and characteristics of radiation-induced immunosuppression. Elevated serum IL-10 in transfused patients may play a role in the disregulation of lymphocyte function, in particular, the depression of NK- and T-cell cytotoxicity. Investigation of alternatives to blood transfusion during RT that do not diminish host immunity is warranted.

Role of zinc and alpha2 macroglobulin on thymic endocrine activity and on peripheral immune efficiency (natural killer activity and interleukin 2) in cervical carcinoma

Decreased natural killer (NK) activity as well as interleukin 2 (IL-2) are risk factors for the progression of cervical carcinoma. NK activity and IL-2 may be thymus controlled. Plasma levels of active thymulin, a zinc-dependent thymic hormone (ZnFTS), are reduced in cancer because of the low peripheral zinc bioavailability. Zinc and thymulin are relevant for normal immune functions. Alpha2-macroglobulin is an inhibitor of matrix metalloproteases (MMPs) against invasive tumour proliferation. Because alpha2-macroglobulin has a binding affinity (Kd) for zinc that is higher than does thymulin, it may play a key role in immune efficiency in cancer. Plasma samples of 22 patients (age range 35-60 years) with locally advanced squamous cervical carcinoma and with FIGO stage Ib2-IIb were examined. They showed reduced active thymulin, decreased NK activity and IL-2 production, increased soluble IL-2 receptor (sIL-2R) and augmented alpha2-macroglobulin in the circulation, whereas plasma zinc levels were within the normal range for age. Significant positive correlations were found between zinc or active thymulin and alpha2-macroglobulin (r = 0.75, P < 0.01, r = 0.78, P < 0.01, respectively) in cancer patients. In vitro zinc increases IL-2 production from peripheral blood mononuclear cells (PBMCs) of cancer patients. These data suggest that an increase in alpha2-macroglobulin, which competes with thymulin for zinc binding, may be involved in causing a thymulin deficit with a consequent decrease of IL-2 and NK cytotoxicity. Thus, physiological zinc treatment in cervical carcinoma maybe restores impaired central and peripheral immune efficiency.