Yoshimura Chie, Nomura Shosaku, Kanazawa Shigenori, Kuwana Midori, Muramatsu Mikiko, Yamaguchi Kazuyuki, Fukuhara Shirou
First Department of Internal Medicine, Kansai Medical University, 10-15 Fumizonocho, Moriguchi, Osaka 570-8507, Japan.
J Cancer Res Clin Oncol. 2002 Nov;128(11):581-8. doi: 10.1007/s00432-002-0381-y. Epub 2002 Oct 25.
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.
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.
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.
Our findings suggest that the effect of immunotherapy may be insufficient for non-small cell lung cancer without HLA-A2.
近年来，有人提出将免疫疗法用于恶性肿瘤的治疗。为探讨免疫疗法对肺癌的意义，我们研究了两个系统：HLA I类分子和癌症反应性CTL系统，以及Fas-FasL系统。
测定了61例肺癌患者和30名健康对照者的HLA I类分子（HLA-A、-B和-C）抗原。采用血清学技术研究HLA I类分子表型。通过聚合酶链反应序列特异性引物分析研究HLA-A2等位基因。我们用双色表面标记和流式细胞术分析了从61例患者中分离出的淋巴细胞。此外，我们通过酶联免疫吸附测定（ELISA）分析了sFas和sFasL的表达。我们还用共聚焦激光扫描显微镜检查了肺癌细胞系诱导的CD8(+)淋巴细胞凋亡。
61例肺癌患者中有27例检测到HLA-A2等位基因。肺癌患者与对照组之间的HLA-A2等位基因分类没有差异。61例肺癌患者中有36例（57%）的sFas水平升高，61例患者中有16例（26.2%）的sFasL水平升高。携带HLA-A2的肺癌患者的sFas水平显著高于不携带HLA-A2的肺癌患者（P<0.01）。在每种肺癌组织类型中均观察到这种趋势，携带HLA-A2的肺癌患者的sFas水平与携带HLA-A2的肺癌患者的CTL水平显著相关。此外，与不携带HLA-A2的肺癌相比，携带HLA-A2的肺癌中CD8(+) T细胞水平升高。相反，不携带HLA-A2的非小细胞肺癌的sFas水平高于携带HLA-A2的肺癌。在使用肺癌细胞系的体外实验中，我们观察到肺癌细胞诱导的CD8(+)淋巴细胞凋亡。肺癌反应性CTL容易通过HLA-A2的限制而被动员，但这种限制并不总是具有特异性。此外，源自肺癌细胞的FasL可诱导CD8(+) T细胞凋亡，在不携带HLA-A2的小细胞肺癌中这种现象的发生率增加。
我们的研究结果表明，对于不携带HLA-A2的非小细胞肺癌，免疫疗法的效果可能不足。
