Analysis of aberrant EGFR in malignant gliomas, and the development of immunochemotherapy using the antibody against the receptor

在恶性胶质瘤中发现异常的EGFR，在细胞外域和细胞内域都有异常。40例胶质母细胞瘤中有14例(35%)有EGFR异常表达。8例EGFR异常位于胞外区，4例位于胞内区，2例同时位于胞外区和胞内区。7例(17.5%)胶质母细胞瘤EGFR表达正常。在17例间变性胶质瘤中，3例(17.6%)表达异常的EGFR，而在低级别胶质瘤中未见表达。在生存时间的统计分析中，18例正常表达的胶质母细胞瘤的平均生存期为440天，6例正常表达的胶质母细胞瘤的平均生存期为354天，11例异常表达的胶质母细胞瘤的平均生存期为318天，这些异常可能与肿瘤的恶性程度有关。我们尝试了脂质体包裹的反义EGFR寡核苷酸(D-寡核苷酸)对三种恶性胶质瘤细胞株的杀伤作用。脂质体包裹的反义EGFR寡核苷酸孵育3d后，对3株恶性胶质瘤细胞的增殖抑制率为30%~10%。受抑制的肿瘤细胞DNA合成活性下降约70%。该寡核苷酸还诱导肿瘤细胞聚集在S期和G2+M期。脂质体包被的反义EGFR寡核苷酸有望成为治疗恶性胶质瘤的最佳基因治疗方法之一。我们正在研制针对这种突变的EGFR的单抗，以用于恶性胶质瘤的诊断和抗恶性胶质瘤的免疫化疗。

Aberrant EGFR found in malignant gliomas, have abnormalities in the extracellular domain and intracellular domain. Aberrant EGFR was found in 14 (35%)/40 glioblastomas. Eight aberrant EGFR had an abnormality in the extracellular domain, 4 had abrromality in the intracellular domain and only 2 had abnormalities in both domains. Overepression of normal EGFR eas found in 7 glioblastomas (17.5%). In 17 anaplastic gliomas, aberrant EGFR was expressed in 3 (17.6%), but aberrant EGFR was not expressed in low grade gliomas, IN the statistical analysis of the survival time, the average survival time was 440 days in 18 patients with glioblastomas showing moderate expression of normal EGFR, 354 days in 6 patients with glioblastomas showing overexpression of normal EGFR, 318 days in 11 patients with glioblastomas demonstrating aberrant EGFR.these abnormalities may have a relationship to malignancy of gliomas whth tyrosine kinase activity. We tried an antisence EGFR oligonucleotide (D-oligonucleotide) enveloped with Lipofectin^R against three malignant glioma cell lines. The antisense EGFR oligonucleotide enveloped with Lipofectin^R inhibited the proliferation in three malignant glioma cell lines from 30 to 10% after three days incubation compared as a control incubation. The DNA synthesis activity in the supressed tumor cells dropped out about 70%. This oligonucleotide also induced accumulation of tumor cells in S and G2 + M phase. An antisense EGFR oligonucleotide enveloped with Lipofectin^R was expected to become one of the best gene therapies against malignant gliomas.We are developing the monoclonal antibody to the aberrant EGFR in order to do a diagnosis of malignant gliomas and do a immunochemotheapy against malignant gliomas.