A Deletion Mutation within the Ligand Binding Domain Is Responsible for Activation of Epidermal Growth Factor Receptor Gene in Human Brain Tumors

Two transplantable cell lines of human glioblastoma multiforme GL-3 and GL-5 carried an amplification and overexpression of structurally altered epidermal growth factor (EGF) receptor gene: the 140 kilodalton EGF receptors in these cases exhibited a constitutively expressed tyrosine kinase activity without the ligand. Here, we isolated the abnormal EGF receptor cDNA from GL-5 cell line, and demonstrated that this cDNA bears a single large intramolecular deletion mutation 801 base pairs long within the ligand binding domain of EGF receptor. In other regions no amino acid substitution was observed. At the level of genomic DNA, this deletion appeared to start from the 1st intron and terminate in the 6th intron of the EGF receptor gene. However, in the two lines of glioblastoma, GL-3 and GL-5, the positions of the start or the end of the deletion mutation in these introns were not identical, suggesting an involvement of a unique recombination mechanism in the formation of deletion mutation. A weak but ligand-independent transforming activity was observed in the deletion-carrying EGF receptor cDNA.     

膀胱移行细胞癌Pgp、突变p 53 蛋白、EGFR 表达的预后判定价值

 目的　探讨 Pgp、突变 p53蛋白、EGFR表达在膀胱移行细胞癌预后方面的判定价值。方法　应用免疫组化 SP法 ,检测 83例随 3年以上、术前未经化疗的原发性膀胱移行细胞癌中Pgp、突变 p53蛋白和 EGFR表达情况。结果　 Pgp、突变 p53蛋白、EGFR的阳性表达率分别为63.9%、74.7%、67.5% ,三者的过表达均与膀胱癌的病理分级、临床分期和复发有关 ;生存分析显示 Pgp、突变 p53蛋白、EGFR表达与患者术后存活率密切相关。结论　Pgp、突变 p53蛋白、EGFR过表达是判定膀胱移行细胞癌恶性程度和预后的重要指标。     

乳腺癌组织中表皮生长因子受体（EGFR）的研究

用￣（１２５）Ｉ标记的表皮生长因子（￣（１２５）Ｉ－ＥＧＦ）作为配基，用标准的ＥＧＦ作为竞争剂，采用单点饱和分析法测定了３６例乳腺癌组织中的ＥＧＦＲ含量，范围在１～１２２ｆｍｏｌ／ｍｇ膜蛋白之间，以１０ｆｍｏｌ／ｍｇ膜蛋白以上为阳性，乳腺癌阳性率为３８％。按乳腺癌临床分期的结果表明，临床分期越高，阳性率也越高。有淋巴结转移者较无淋巴结转移的病人阳性率有增高趋势。证明表皮生长因子受体与乳腺癌的恶性程度有关，但癌各组织学类型之间阳性率未见差别。     

Immunohistochemical Study of Estradiol, Epidermal Growth Factor, Transforming Growth Factor Alpha and Epidermal Growth Factor Receptor in Endometrial Neoplasia

In a total of 113 cases of endometrial neoplasm, we studiedthe immunohistochemical expression of estradiol (E2), epidermalgrowth factor (EGF), transforming growth factor alpha (TGF),and epidermal growth factor receptor (EGFR). Positive immunoreactivityof E2 was found in 61% of the neoplasms. E2 immunoreactivitycorrelated well with high histologic grade and early clinicalstage. Positive immunoreactivity for ECF or ECFR was found in25.6% or 53.1% of the neoplasms, respectively. However, thiswas unrelated to histologic grade or clinical stage. On theother hand, TGF immunoreactivity was found in 67% of endometrialneoplasias and was correlated with poor histologic grade andadvanced stage. Contingency tables indicated a significant negativeassociation between the status of E2 and that of TGF. Simultaneousexpression of E2, EGF and EGFR, or E2, TGF and EGFR was foundin 6.8% and 15.9% of endometrial carcinomas, respectively. Theseresults suggest that a predominant number of endometrial carcinomasescape autocrine/paracrine growth regulation by EGF and E2 orTGF and E2, and that TGF may be involved in the progressionof endometrial carcinoma.     

Radioimmunoscintigraphy of Intracranial Glioma Xenograft with a Technetium-99m-Labeled Mouse Monoclonal Antibody Specifically Recognizing Type III Mutant Epidermal Growth Factor Receptor

The type III mutant epidermal growth factor receptor (EGFR) is expressed on the cell surface of a subset of glioma, but not of normal tissues. In this study, we investigated the in vivo kinetics of 3C10 mouse monoclonal antibody (mAb), specifically recognizing the type III mutant EGFR (EGFRvIII), using athymic nude mice bearing the intracranial glioma xenograft overexpressing the EGFRvIII.Human glioma cell line, U87MG, expressing the wild type EGFR and the transfectant, named U87MGEGFR, expressing the EGFRvIII, were transplanted subcutaneously or intracranially to nude mice. 3C10 mAb labeled with a technetium-99m (^99mTc) was intravenously injected into these nude mice and then the mice were sacrificed at 24h later, and the ^99mTc-uptake by xenografts and major normal organs was measured to determine the biodistribution of mAb. Furthermore, at 3, 6 and 24h after injection of ^99mTc-labeled 3C10 mAb, whole-body scintigraphy was obtained with a gamma camera to localize the tumor site.3C10 mAb significantly accumulated to U87MGEGFR xenografts transplanted subcutaneously or intracranially in nude mice, showing high tumor-to-blood ratio of 10.30 and 4.01, respectively. In contrast, uptake of control antibody in the intracranial tumor was as low as 0.43. In scintigrams, intracranially transplanted U87MGEGFR xenografts were detectable at 3h after injection of ^99mTc-labeled 3C10 mAb.These results suggest that intravenously injected 3C10 mAb specifically accumulated to the subcutaneous or intracranial glioma xenograft expressing the EGFRvIII and 3C10 mAb is a potential diagnostic and therapeutic agent for patients with gliomas expressing the EGFRvIII.     

表皮生长因子受体在喉癌及癌前病变中的表达

目的：探讨表皮生长因子受体的表达在喉癌和癌前病变中的作用。方法：应用免疫组化ＡＢＣ法检测喉鳞癌３１例,喉上皮非典型增生１６例,正常喉粘膜１０例的表皮生长因子受体（ＥＧＦＲ）的表达。结果：发现正常喉粘膜组织全部阴性,喉癌的ＥＧＦＲ阳性率为４８％,非典型增生ＥＧＦＲ的阳性率为５６％,并随异型增生程度的增高ＥＧＦＲ表达增加,其差异有显著性（Ｐ〈０．０５）。但ＥＧＦＲ的表达与喉癌发生部位、肿瘤分期、组织分     

Expression of Epidermal Growth Factor, Transforming Growth Factor-α and Their Receptor Genes in Human Gastric Carcinomas; Implication for Autocrine Growth

The expressions of mRNA for epidermal growth factor (EGF), transforming growth factor-α (TGF-α) and EGF receptor (EGFR) genes were examined in 7 human gastric carcinoma cell lines and 15 gastric carcinoma tissues and the corresponding normal mucosas. All of the gastric carcinoma cell lines expressed mRNA for EGFR and TGF-α genes. TMK-1 and MKN-28 cells also expressed EGF mRNA. Production of EGF, TGF-α and EGFR protein by gastric carcinoma cell lines was also confirmed by EGF and TGF-α specific monoclonal antibody binding. As for surgical specimens, EGFR and TGF-α mRNA were detected at high levels in all the tumor tissues. Interestingly, EGF mRNA was detected in 5 (33.3%) of the 15 gastric carcinomas but it was not detected in normal tissues. Moreover, anti-EGF and anti-TGF-α monoclonal antibodies inhibited the spontaneous ³H-TdR uptake by gastric carcinoma cells. These results suggest that EGF and/or TGF-α produced by tumor cells act as autocrine growth factors for gastric carcinomas.     

表皮生长因子受体表达与乳腺癌激素受体水平和预后的关系

应用免疫组化ＡＢＣ方法研究７５例乳腺癌冰冻组织表皮生长因子受体（ＥＧＦＲ）的表达，结合临床资料和ＥＲ、ＰＲ测定结果进行分析，探讨ＥＧＦＲ表达与乳腺癌预后的关系。结果表明，ＥＧＦＲ阳性３０例（４０％），ＥＧＦＲ表达与肿瘤大小、腋淋巴结状况，临床分期和年龄无关，与ＥＲ、ＰＲ存在着显著的负相关（Ｐ＜０．００５）。全组中位随诊时间为６０个月，ＥＧＦＲ阳性组术后总生存率明显低于阴性组（Ｐ＜０．００１）。在无腋淋巴结转移的病例中，ＥＧＦＲ阳性组和阴性组术后生存情况也有显著差异（Ｐ＜０．０１），提示ＥＧＦＲ表达与乳腺癌不良的预后有关。调整分析乳腺癌有关的预后因素，各组病例中均以ＥＧＦＲ表达阳性组的预后为差，说明ＥＧＦＲ对乳腺癌预后具有独立的作用，不受其他因素的影响。经Ｃｏｘ模型多因素分析显示，ＥＧＦＲ和腋淋巴结受累与否是对乳腺癌术后生存情况有显著性影响的两个因素。     

选择性EGFR 酪氨酸激酶抑制剂吉非替尼对宫颈癌离体细胞的放射增敏作用

 目的 探讨表皮生长因子受体酪氨酸激酶抑制剂吉非替尼对宫颈癌离体细胞的放射增敏作用。方法 以宫颈鳞癌Siha细胞，腺癌HeLa细胞为研究对象，利用MTT法检测吉非替尼对Siha和HeLa细胞的增殖抑制作用；利用集落形成实验检测吉非替尼对Siha、HeLa细胞的放射增敏效应。结果 吉非替尼能够抑制Siha、HeLa细胞的增殖，其JC20，值分别是0．15μmol／L、0．32μmol／L，而且抑制作用呈剂量依赖性；吉非替尼作用于Siha、HeLa细胞72h后，放射增敏比SER分别为1．693、1．228。结论 吉非替尼对宫颈癌Siha、HeLa细胞具有明显的放射增敏作用。     

胰腺癌组织中表皮生长因子受体、基质金属蛋白酶9的表达及其意义

目的 探讨胰腺癌组织中表皮生长因子受体(EGFR)、基质金属蛋白酶9(MMP-9)的表达及其 与胰腺癌临床病理特征的关系。方法 应用免疫组织化学SP法检测44例胰腺癌、相应癌旁胰腺组织、 13例慢性胰腺炎和7例正常胰腺组织中EGFR、MMP-9的表达,并分析其与临床病理特征的相关性。 结果 正常胰腺组织中均无EGFR及MMP-9的表达。慢性胰腺炎组织中EGFR、MMP-9的阳性表达 率分别为23.1%(3/13)和15.4%(2/13)。胰腺癌组织中EGFR、MMP-9的阳性表达率分别为61.4%(27/44) 和54.5%(24/44);相应癌旁组织中的阳性表达率分别为34.1%(15/44)和29.5%(13/44)。胰腺癌组织中 的EGFR及MMP-9阳性表达率均显著高于相应癌旁组织(P<0.05);胰腺癌组织及癌旁组织中EGFR及 MMP-9的表达均显著高于慢性胰腺炎组织和正常胰腺组织(P均<0.05)。EGFR和MMP-9的表达与胰腺 癌临床分期、分化程度、血管侵犯及淋巴结转移相关。结论 胰腺癌组织中EGFR的表达与MMP-9表 达密切相关,EGFR的表达与MMP-9的表达水平可作为了解胰腺癌生物学行为和判断预后的指标。     

C－erbB－2，人表皮生长因子及其受体在大肠癌中表达的意义

用ＡＢＣ免疫组化法测定２００例大肠癌组织中Ｃ－ｅｒｂＢ－２，人表皮生长因子（ｈＥＧＦ）及其受体（ＥＧＦＲ）。结果发现：１）Ｃ－ｅｒｂＢ－２，ｈＥＧＦ，ＥＧＦＲ在２００例大肠癌中阳性表达分别为３６％、４４％、４７％，三者共同阳性为１６．５％。２）ｈＥＧＦ，ＥＧＦＲ在大肠癌ＤｕｋｅｓＣ、Ｄ期，肿瘤＞２ｃｍ、低分化腺癌，有深度浸润和淋巴结转移者阳性率显著高于其它各型（Ｐ＜０．０１）。３）Ｃ－ｅｒｂＢ－２，ｈＥＧＦ和ＥＧＦＲ阳性病例存活率明显低于这些阴性病例（Ｐ＜０．０１）。结果表明，Ｃ－ｅｒｂＢ－２，ｈＥＧＦ和ＥＧＦＲ在大肠癌的侵袭性生长中起重要作用，ｈＥＧＦ和ＥＧＦＲ可作为大肠癌患者高度恶性的生物学指标。     

Evaluation of Novel Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors

The epidermal growth factor system is a well characterized growth factor receptor pathway, the deregulation of which has been be associated with neoplastic growth. Overexpression or amplification of the epidermal growth factor receptor (EGFR) or one of its ligands has been linked with the malignant transformation of cells and is correlated with poor prognosis in patients. PD 153035, a quinazoline, has been shown to inhibit the tyrosine kinase activity of EGFR by blocking ATP binding (Fry et al., Science 265: 1093-1095, 1994). We set out to determine whether the growth inhibition caused by this agent and five related compounds is a direct result of the blocking of EGFR signaling. The effects on cell proliferation produced by these agents were tested on several tumor cell lines and EC50 values obtained. The EGF responsive cell lines A-431 and MDA-MB-468 exhibit EC50 values of 3 and 6.7 micro M, respectively, for PD 153035 which was found to be the most potent. The agents were then tested for their ability to block the paradoxical high dose EGF induced inhibition of A-431 and MDA-MB-468 cell growth as well as EGF induced phosphorylation in A-431 cells. These compounds are able to completely block the effects of exogenously added EGF at 0.5 microM or less. However, higher doses (EC50's >or= 2 microM) were needed to block the growth of human tumor cell lines potentially implicating a second site of action for these compounds.     

表皮生长因子受体的表达与喉癌预后关系的初步研究

采用免疫组化ＬＳＡＢ法，用抗ＥＧＦ－Ｒ单克隆抗体对３８例喉鳞状细胞癌进行标记，用图像分析技术对染色结果定量分析， 阳性单位ＰＵ值代替染色级别。结果显示：喉鳞状细胞癌Ⅲ极的ＰＵ值明显高于Ⅰ－Ⅱ级的ＰＵ值，淋巴结转移组的ＰＵ值高于无淋巴结转移组的ＰＵ值，取得完整随访资料３４例，绘ａｐｌａｎ－Ｍｅｉｅｒ生存曲线，经Ｌｏｇｒａｎｋ检验，ｘ＾２＝８．６２，Ｐ〈０．０５。