Elevation of soluble interleukin-2 receptor in patients with non-small cell lung cancer treated with gefitinib.

PURPOSE: We previously reported that plasma thromboxan B(2), soluble P-selectin, and serum regulated on activation, normal T-cell expressed and secreted (RANTES) were elevated after gefitinib treatment. We hypothesized that gefitinib could activate T-lymphocytes via activated platelets, and so we measured serum levels of soluble interleukin-2 receptor (sIL-2R) in patients medicated with gefitinib. METHODS: Twenty-one patients with non-small cell lung cancer (NSCLC) were entered into this study. All patients received gefitinib over 2 weeks without severe adverse effects. Blood samples were withdrawn from all patients before and after the administration of gefitinib and plasma soluble P-selectin, serum RANTES, and serum sIL-2R were measured by enzyme-linked immunosolvent assay. In addition, we carried out the basic study of the interleukin-2 receptor (IL-2R) expression on CD4(+) lymphocytes by RANTES. RESULTS: Plasma soluble P-selectin, serum RANTES, and serum sIL-2R levels increased significantly in patients receiving gefitinib treatment for 1 and 2 weeks. RANTES did not induce the expression of IL-2R on CD4(+) lymphocyte. However, the anti-CD3 monoclonal antibody-induced expression of IL-2R was enhanced by the addition of RANTES. CONCLUSION: Our finding indicated that lymphocytes were activated by gefitinib treatment. We think that sIL-2R elevation after gefitinib administration may be a factor positively effecting patients with NSCLC. It is deemed possible that the effect of gefitinib is induced not only by its blocking of the tyrosine kinase of epidermal growth factor receptor but also by antitumor immunity via its activation of T-cells.

Gefitinib affects functions of platelets and blood vessels via changes in prostanoids balance.

Prostaglandins (PGs) and thromboxane (TX) produced by cyclooxygenase (COX) have a great influence on vascular systems and platelet functions. The serum levels of epidermal growth factor (EGF) and PGs were measured in patients with lung cancer treated with gefitinib, and the influence of EGF on platelet aggregation was investigated. Twenty patients were investigated. The serum level of TXB(2) increased significantly in all patients who received gefitinib for 2 weeks (before vs. after = 94.1 +/- 47.3 vs. 190.9 +/- 54.3, p<0.01). TXB(2) also increased significantly in responders without concurrent chemotherapy (before vs. after = 79.3 +/- 35.5 vs. 194.5 +/- 58.1, p<0.05), but not in non-responders (before vs. after = 106. 5 +/- 65.8 vs. 162.2 +/- 52.8, N.S.). PG 6-keto F1alpha and PGE(2) did not exhibit significant changes. Furthermore, EGF showed no significant change (after vs. before = 234 +/- 35 vs. 276 +/- 72, N.S.). Although there was no correlation between the levels of EGF and TXB(2) (N.S.), the PG 6-keto F2alpha/TXB(2) ratio decreased significantly (before vs. after = 0.054 +/- 0.018 vs 0.033 +/- 0.015, p<0.05). The secondary platelet aggregation observed after high-dose adenosine diphosphate stimulation was inhibited after a 1-minute preincubation with EGF. Platelet aggregation in patients after gefitinib administration tended to accelerate and secondary aggregation was observed after low-dose adenosine diphosphate stimulation. We conclude that careful observation is needed for patients with chronic obstructive pulmonary disease, pulmonary fibrosis, and thromboembolic diseases receiving gefitinib. Furthermore, measurement of prostanoids may be a good predictor of the beneficial and adverse effects. Moreover, the combination of gefitinib with a COX inhibitor that regulates TXA(2)/PGI(2) balance should be evaluated.

Monocyte-derived microparticles may be a sign of vascular complication in patients with lung cancer.

We measured and compared the levels of plasma monocyte-derived microparticles (MDMP) and platelet activation markers [plasma platelet-derived microparticles (PDMP), CD62P binding to platelets; plt-CD62P, CD63 binding to platelets; plt-CD63], to develop a better understanding of their potential contribution to vascular complications of lung cancer. The concentrations of MDMP and PDMP in lung cancer patients were significantly higher (P < 0.01) than those in normal subjects. Levels of plt-CD62P and plt-CD63 were significantly higher (P < 0.001 for each) in lung cancer patients than in controls. Levels of sE-selectin were also higher in lung cancer patients than in control subjects. MDMP correlated positively with plt-CD62P, plt-CD63, and PDMP with its relation to PDMP being particularly significant. The number of MDMPs and PDMPs are patients who are non-small cell lung cancer were significantly higher than that in small cell lung cancer patients. In addition, levels of sE-selectin were higher in non-small cell lung cancer than in small cell lung cancer patients. These findings suggest that elevated MDMPs may be a sign of vascular complication in lung cancer patients, particularly those who suffer from non-small cell lung cancer.

Analysis of cytotoxic T lymphocytes and Fas/FasL in Japanese patients with non-small cell lung cancer associated with HLA-A2.

PURPOSE: In recent years, the use of immunotherapy for malignant tumors has been proposed. To explore the significance of immunotherapy for lung cancer, we examined two systems : the HLA class I and cancer-reactive CTL system, and the Fas-FasL system. METHODS: HLA class I (HLA-A, -B, and -C) antigens were determined in 61 patients with lung cancer and in 30 healthy controls. The HLA class I phenotype was investigated by serological techniques. HLA-A2 alleles were investigated by polymerase chain reaction sequence-specific primer analysis. We analyzed lymphocytes isolated from 61 patients with two-color surface labeling and flow cytometry. Furthermore, we analyzed sFas and sFasL expression by enzyme-linked immunosorbent assay (ELISA). We also examined lung cancer cell line-induced apoptosis of CD8(+) lymphocytes using confocal laser scanning microscopy. RESULTS: The HLA-A2 allele was observed in 27 of 61 patients with lung cancer. There were no differences in HLA-A2 allele classifications between lung cancer patients and controls. Thirty-six of the 61 lung cancer patients (57%) had elevated levels of sFas, and 16 of the 61 patients (26.2%) had elevated levels of sFasL. The sFas level of lung cancers with HLA-A2 was significantly higher than that of cancers without HLA-A2 ( P<0.01). This tendency was observed in every lung cancer tissue type, and the sFas levels of lung cancers with HLA-A2 associated significantly with the CTL levels of lung cancers with HLA-A2. Furthermore, compared to lung cancers without HLA-A2, CD8(+) T-cell levels were elevated in lung cancers with HLA-A2. In contrast, sFas levels of non-small cell lung cancers without HLA-A2 were higher than those in lung cancers with HLA-A2. In an in vitro experiment using lung cancer cell lines, we observed apoptosis of CD8(+) lymphocytes induced by lung cancer cells. Lung cancer-reactive CTLs are mobilized easily by restriction of HLA-A2, but this restriction is not always specific. In addition, FasL derived from lung cancer cells can induce apoptosis of CD8(+) T-cells, and the frequency of this phenomenon is increased in small cell lung cancers without HLA-A2. CONCLUSION: Our findings suggest that the effect of immunotherapy may be insufficient for non-small cell lung cancer without HLA-A2.

Aspirin reduces adverse effects of gefitinib.

We measured serum levels of soluble (s) P-selectin and thromboxane B2 (TxB2) in patients with lung cancer treated with gefitinib, and investigated the effect of low-dose aspirin on some adverse effects of gefitinib. The serum levels of sP-selectin and TxB2 increased significantly in all patients who received gefitinib for 2 weeks. Forty patients were recruited, and 28 received gefitinib without low-dose aspirin (Group 1) and 12 were co-administered low-dose aspirin (Group 2). In Group 2, the frequency of adverse events, skin rash and diarrhea was evidently reduced by the low-dose aspirin therapy, despite having shown no remarkable change in gefitinib responsiveness between both groups. In one of the 12 patients in Group 2, aspirin therapy was suspended due to the occurrence of nasal bleeding. Four days after treatment suspension, she developed a skin lesion in her finger. However, the skin lesion improved after re-administration of aspirin without any other medications. After treatment, TxB2 significantly decreased, but not sP-selectin. These results suggest that one of the mechanisms causing gefitinib-related adverse effects depends on platelet activation. Administration of gefitinib with low-dose aspirin to lung cancer patients may prevent the development of gefitinib-related complications.