转化生长因子α及其受体促进肝癌细胞生长

已经发现转化生长因子α（ＴＧＦα）及其受体表皮生长因子受体（ＥＧＦＲ）在多种人类恶性肿瘤中有表达，并与这些肿瘤病人的预后有密切关系。本实验观察了体外培养人肝癌细胞，荷人肝癌裸鼠模型，以及肝癌病人的肿瘤标本中ＴＧＦα和ＥＧＦＲ的表达及其与肝癌生长的关系。结果显示两种裸鼠模型中，ＥＧＦＲ表达强的肿瘤生长快；培养肝癌细胞在ＴＧＦα刺激下ＥＧＦＲ表达明显增强，同时细胞分裂指数也明显增加；在一组人肝癌标本中     

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。     

表皮生长因子受体和血管内皮生长因子在非小细胞肺癌中的表达及意义

目的　观察非小细胞肺癌（ＮＳＣＬＣ）组织中表皮生长因子受体（ＥＧＦＲ）和血管内皮生长因子（ＶＥＧＦ）的表达情况以及与临床病理参数的关系。方法　免疫组织化学法检测７６例ＮＳＣＬＣ组织和１４例非恶性肺组织ＥＧＦＲ和ＶＥＧＦ的表达。结果　ＥＧＦＲ和ＶＥＧＦ在７６例ＮＳＣＬＣ组织中的阳性表达率分别为４７.４％（３６／７６）和５１.３％（３９／７６）,在１４例非恶性肺组织表达率分别为７１４％（１／１４）和７.１４％（１／１４）,两组ＥＧＦＲ、ＶＥＧＦ表达差异显著（Ｐ＜０.０５）。Ⅲ期ＮＳＣＬＣ组织的ＥＧＦＲ表达率为５６.８％（２５／１９）,高于Ⅰ ～Ⅱ期患者的３１.３％（１０／３２）,两者差异显著（Ｐ＜０.０５）,ＥＧＦＲ表达与其他临床病理参数均无关;淋巴结阳性的ＮＳＣＬＣ组织ＶＥＧＦ表达率为７７.８％（２８／３４）,明显高于淋巴结阴性的２７.５％（１１／４２）,两者差异显著（Ｐ＝０.０００）,ＶＥＧＦ表达与肿瘤分期、性别、年龄、肿瘤细胞分化等临床病理参数亦无关。ＥＧＦＲ和ＶＥＧＦ在ＮＳＣＬＣ组织中表达无相关性（Ｐ＞０.０５）。结论　ＮＳＣＬＣ组织中ＥＧＦＲ和ＶＥＧＦ常常为高表达,ＥＧＦＲ表达与肿瘤的ＴＮＭ分期有关,ＶＥＧＦ与淋巴结转移有关;但是ＥＧＦＲ和ＶＥＧＦ的表达之间无相关性。     

胃癌上皮生长因子及其受体与雌激素受体的表达及相互关系

用免疫组化ＡＢＣ方法，检测胃癌和正常胃粘膜中上皮生长因子（ＥＧＦ）及其受体（ＥＧＦＲ）、雌激素受体（ＥＲ）的表达。结果：６４例胃癌中，ＥＧＦ阳性３９例（６０．９％），ＥＧＦＲ阳性３３例（５１．６％），ＥＲ阳性１２例（１８．８％）；５８例正常胃组织中，ＥＧＦ、ＥＧＦＲ阳性各３例，ＥＲ阴性。癌与正常对照组间差异有显著性（Ｐ＜０．０５）。提示，ＥＧＦ、ＥＧＦＲ、ＥＲ与胃癌有关。胃癌ＥＧＦ、ＥＧＦＲ的阳性率又非常显著高于ＥＲ（Ｐ＜０．００５），说明ＥＧＦ、ＥＧＦＲ在胃癌发展中的调节作用远较雌激素重要。结果还提示，ＥＧＦ、ＥＧＦＲ、ＥＲ的相互关系影响胃癌细胞的发生、种植和转移。     

乳腺癌上皮生长因子受体的临床病理观察及预后意义

用免疫组化法检测了８９例乳腺癌的上皮生长因子受体（ＥＧＦＲ）表达状况，并结合其雌激素受体（ＥＲ）表达和ＤＮＡ含量的分析结果，发现乳腺癌ＥＧＦＲ的阳性率为３９．３％，ＥＧＦＲ阳性乳癌中ＥＲ的阳性率为１１．４％（４／３５），而ＥＧＦＲ阴性组中ＥＲ阳性率为７７．８％（４２／５４），两者阳性率的分布状况有显著性差异（Ｐ〈０．０１）；同样，经流式细胞术ＦＣＭ分析，ＥＧＦＲ为阳性的乳癌组异倍体出现率也明显高于     

ＥＧＦＲ和ＶＥＧＦ在大肠癌组织中的表达及临床意义

目的：通过免疫组化检测表皮生长因子受体（ＥＧＦＲ）、血管内皮生长因子（ＶＥＧＦ）在大肠癌（ＣＲＣ）和大肠正常组织中的表达,探讨其与临床病理特征的相关性。方法：应用免疫组化ＥｎＶｉｓｉｏｎ法检测５８例大肠癌组织（其中２０例患者年龄＜４０岁）和癌旁正常组织２８例中的ＥＧＦＲ和ＶＥＧＦ的表达水平,并结合临床资料进行统计学分析。结果：大肠癌组织中的ＥＧＦＲ和ＶＥＧＦ阳性表达率分别为４３.１０％和４８.２７％;癌旁正常组织ＥＧＦＲ和ＶＥＧＦ阳性表达率分别为７.１４％和１０.７１％,大肠癌组织中ＥＧＦＲ和ＶＥＧＦ表达率均明显高于癌旁正常组织（Ｐ＜０.０１）。ＥＧＦＲ和ＶＥＧＦ的表达与大肠癌的ＴＮＭ分期以及有无淋巴结转移有关（Ｐ＜０.０５）。ＥＧＦＲ和ＶＥＧＦ阳性表达率在年龄＜４０岁的大肠癌组明显高于其在年龄≥４０岁的大肠癌组（Ｐ＜０.０５）;在年龄＜４０岁的大肠癌组中,两者共阳性表达伴淋巴结转移率高（Ｐ＜０.０１）。结论：ＥＧＦＲ和ＶＥＧＲ在大肠癌组织中高表达,与大肠癌临床分期及淋巴结转移密切相关,可作为临床判断转移及预后等生物学行为的重要参考指标。年龄＜４０岁的早发性大肠癌具有更高的ＥＧＦＲ和ＶＥＧＦ阳性率及共表达率,提示其侵袭性更强、预后更差。     

胃癌中幽门螺杆菌感染与表皮生长因子及其受体表达的研究

目的探讨幽门螺杆菌感染与表皮生长因子的表达与胃癌的关系。方法应用ＰＣＲ法及快速尿素酶法检测幽门螺杆菌（ＨＰ）,免疫组化法（ＡＢＣ法）检测表皮生长因子（ＥＧＦ）和表皮生长因子受体（ＥＧＦＲ）,对３０例胃癌,３０例癌前病变,３０例慢性胃炎的病理组织进行了检测。结果胃癌组ＨＰ的阳性率为４６７％,癌前病变组为７６７％,胃炎组为７０％,胃癌组的ＨＰ阳性率低于癌前病变组和慢性胃炎组,胃癌组的ＥＧＦ和ＥＧＦＲ表达明显强于其它两组,癌前病变组的ＥＧＦＲ表达强于胃炎组（Ｐ＜００１）。另外,ＨＰ阳性组的ＥＧＦＲ阳性表达强于ＨＰ阴性组（Ｐ＜０００５）。结论ＨＰ感染与胃癌及癌前病变有关,ＨＰ感染可能主要作用于癌变的起始阶段;ＥＧＦ和ＥＧＦＲ在胃癌有很强的表达。     

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。     

鼻咽癌内血管内皮生长因子的表达及其病理临床意义初探

目的探讨血管内皮生长因子（ＶＥＧＦ）在鼻咽癌中的表达及其与病理、临床各因素之间的关系。方法利用免疫组化ＳＰ方法检测１０例鼻咽正常粘膜、１６例鼻息肉及５６例鼻咽鳞癌石蜡标本中ＶＥＧＦ的表达,用Ⅷ因子相关抗原显示肿瘤内的微血管数。结果鼻咽正常粘膜中ＶＥＧＦ均为阴性;１６例鼻息肉中有２例粘膜层呈ＶＥＧＦ阳性表达;鼻咽癌中ＶＥＧＦ表达阳性率为７１．４％（４０／５６）。ＶＥＧＦ阳性组血管密度明显高于ＶＥＧＦ阴性组（Ｐ＜０．０５）;ＶＥＧＦ的表达也与放疗后局部复发、远地转移及预后差有关,但与肿瘤的组织学分级及临床分期无关。结论ＶＥＧＦ表达与肿瘤血管生成有关,也是预测鼻咽癌复发、远地转移以及预后差的有用指标。     

血管内皮生长因子在大肠癌中的表达及预后价值

目的：研究血管内皮生长因子（ＶＥＧＦ）在朋肠癌中的表达及其与临床病理特征的关系。方法：采用免疫组织化学方法检测８０例大肠癌手术标本肿瘤组织内的血管内皮生长因子（ＶＥＧＦ）和微血管计数（ＭＶＤ）。结果：ＶＥＧＦ表达阳性率为６１．２％,ＶＥＧＦＤ表达阳性的肿瘤组织其ＭＶＤ明显高于阴性者（Ｐ＜０．０５）。ＶＥＧＦ表达与肿瘤的浸润性生长、浆膜浸润、淋巴结转移和肝转移有明显相关性（Ｐ＜０．０５）。此外,ＶＥ     

吉非替尼对肺癌细胞株HCC827和H358放射敏感性的影响及其机制研究

背景与目的表皮生长因子受体(epidermal growth factor receptor,EGFR)是决定放疗效应的一个重要因素,其过表达或是下游通路的激活与包括非小细胞肺癌在内的肿瘤的放疗抵抗相关,因而阻断EGFR的信号通路可能会增强放疗敏感性。本研究旨在探讨小分子EGFR酪氨酸激酶抑制剂吉非替尼能否增加肺癌细胞株HCC827和H358的放疗敏感性及其可能的机制。方法选取HCC827和H358这两个非小细胞肺癌细胞株,分为单纯X线组和X线+吉非替尼两组。单纯X线组采用单纯X线照射,X线+吉非替尼组经1μmol/L吉非替尼作用24h后再行X线照射。克隆形成实验比较两株细胞中不同分组细胞放射敏感性,免疫荧光激光共聚焦显微镜观察X线照射后各时间点细胞核中的磷酸化H2AX(γ-H2AX)及EGFR焦点在细胞中的定位情况,Western blot法检测放疗后胞质胞核蛋白中EGFR的表达。结果克隆形成实验中,H358细胞实验组与对照组在各放疗剂量点的SF2值分别为0.355和0.433;HCC827细胞实验组与对照组在各放疗剂量点的SF2值分别为0.223和0.242,差别不明显。激光共聚焦显微镜观察照射4Gy后各时间段实验组H358细胞核中g-H2AX斑点相比对照组要多,且持续时间更长。而对照组和实验组的HCC827细胞g-H2AX斑点在各时间段并无明显差异;激光共聚焦显微镜观察照射4Gy后对照组H358的EGFR蛋白在1h内入核,而经吉非替尼处理后EGFR蛋白几乎不入核;实验组及对照组HCC827细胞的EGFR表达位置均在细胞质中,胞核中很少或者没有,可以认为并无入核现象;Western blot结果显示,H358细胞在经4Gy放射处理后有入核现象,而预先经吉非替尼处理后,EGFR蛋白几乎不在核内表达而仍位于细胞浆内。对于HCC827细胞,实验组及对照组的EGFR蛋白均在细胞质中表达,胞核中很少或没有,且两组并无明显差异。结论吉非替尼可增加肺癌细胞株H358的放射敏感性,这可能与其阻止放疗后EGFR入核、影响放疗后双链断裂(double strand break,DSB)修复有关;而对HCC827细胞无影响,可能与其放疗后EGFR不入核相关。     

EGF mRNA和EGFR mRNA在肝细胞癌组织中的表达及其意义

背景和目的有众多证据表明表皮生长因子受体(epidermalgrowthfactorreceptor,EGFR)家族在一系列恶性肿瘤的发生发展中起重要作用,但EGFR与肝癌的关系目前尚未明确。本文旨在探讨表皮生长因子(epidermalgrowthfactor,EGF)及其受体的mRNA在人肝细胞癌(hepatocellularcarcinoma,HCC)组织中的表达及其意义。方法用逆转录聚合酶链反应(RT-PCR)技术检测60例HCC患者癌组织及癌旁肝组织中EGFmRNA和EGFRmRNA的表达情况。结果EGFmRNA阳性率在肝癌组织中(60%,36/60)显著低于癌旁组织(80%,48/60)(P<0.05);EGFRmRNA阳性率在肝癌组织中(60%,36/60)显著高于癌旁组织(41.67%,25/60)(P<0.05)。EGFRmRNA在肝癌组织中的检出率与临床分期、门静脉癌栓、肝外转移、术后复发、肿瘤数目等明显有关,而与肿瘤直径、血清AFP水平、分化程度以及癌旁肝硬化无明显关系。EGFmRNA检出率与肿瘤直径明显有关,而与临床分期、门静脉癌栓、肝外转移、术后复发、肿瘤数目、血清AFP水平、分化程度以及癌旁肝硬化等无明显关系。结论本研究结果提示EGF可能与肝癌的发生、发展无关;而EGFR与肝癌的发生、发展及术后复发有关;可作为预测肝癌复发、转移的参考指标。     

EGF和EGFR在肝细胞癌中的表达及临床意义

目的研究表皮生长因子(EG F)及其受体(EG FR)在肝细胞癌(H C C)组织中的表达及其与临床病理的关系。方法应用免疫组化S蛳P方法检测55例H C C患者癌组织及癌旁肝组织中EG F和EG FR的表达情况。结果在55例H C C患者癌组织及其癌旁组织中,EG F阳性表达率分别为54.55%(30/55)和76.36%(42/55),两者差异有显著性(P<0.05);EG FR阳性表达率分别为58.18%(32/55)和36.36%(20/55),两者差异有显著性(P<0.05)。EG FR在H C C组织中的阳性表达率与临床分期、门静脉癌栓、肝外转移、术后复发等显著相关,而与肿瘤直径、肿瘤数目、血清AFP水平以及分化程度无明显关系。EG F阳性表达率与各临床病理参数无关。结论EG F可能与H C C的发生、发展无关;而EG FR与H C C的发生、发展有关,可作为预测H C C复发、转移的参考指标。     

Epidermal growth factor receptor (EGFR) status in primary colorectal tumors does not correlate with EGFR expression in related metastatic sites: implications for treatment with EGFR-targeted monoclonal antibodies.

PURPOSE: We hypothesized that the detection of epidermal growth factor receptor (EGFR) expression performed in primary tumors for treatment with EGFR-targeted monoclonal antibodies could not always correlate with EGFR status in metastatic sites, thus making cancer cells in these sites resistant to therapy. The aim of our study was to correlate EGFR expression on primary tumors and related metastases in order to find out whether assessing EGFR status on primary cancer is to be considered an effective tool for planning treatment with EGFR-targeted antibodies. PATIENTS AND METHODS: We retrospectively evaluated EGFR immunohistochemistry from primary tumors and related metastatic sites in 99 colorectal cancer patients. The site of primary tumor was colon in 77 patients (78%) and rectum in 22 patients (22%). Metastatic sites analyzed were liver in 84 patients (81%), lung in 13 patients (13%), bone in one patient (1%), and brain in five patients (5%). EGFR status was defined as positive if the percentage of malignant cells stained was > or = 1%. RESULTS: EGFR status was positive in 53 primary tumors (53%). In 19 primary tumors expressing EGFR (36%), the corresponding metastatic site was found negative, whereas it was found positive in seven metastases (15%) from EGFR-negative primary cancers. The difference between these two groups of patients (ie, EGFR-positive to EGFR-negative v EGFR-negative to EGFR-positive) was statistically significant (P = .036). CONCLUSION: Our results suggest that the detection of the EGFR in primary colorectal cancer could be inadequate for planning therapy with EGFR-targeted monoclonal antibodies in a considerable proportion of both EGFR-positive and -negative primary tumors (36% and 15%, respectively).     

Blockage of epidermal growth factor receptor by quinazoline tyrosine kinase inhibitors suppresses growth of human hepatocellular carcinoma

Epidermal growth factor receptor (EGFR) is highly expressed in many human tumors including hepatocellular carcinoma (HCC). Therefore, inhibition of EGF receptors could be a potential target for anticancer therapy. In this study, we investigated the effects of two EGFR tyrosine kinase inhibitors, PD153035 and its analogue 4-[[3-chloro-4-fluorophenyl]amino]-6,7-dimethoxyquinazoline hydrochloride (ANAPD) on human HCC cell lines by cell proliferation assay, flow cytometry and Western blot. Our results demonstrated that both EGFR inhibitors inhibited tumor cell growth in a dose-dependent manner, but ANAPD was more potent than PD153035. These specific inhibitors not only blocked EGF-stimulated EGFR autophosphorylation but also targeted EGFR signaling including MAPK and Akt pathways. Furthermore, EGFR inhibitors induced a delay in cell cycle progression and a G(1) arrest together with a partial G(2)/M block. EGFR inhibitors also induced tumor cells to undergo apoptosis. In conclusion, this study demonstrated that both PD153035 and ANAPD inhibit tumor cell growth in HCC through inhibition of EGFR signaling pathway, and ANAPD is a more potent inhibitor than PD153035. This suggested that blockage of EGF receptors may provide an effective therapeutic approach for human HCC and ANAPD could be a potential drug candidate for the treatment of HCC.     

Epidermal growth factor receptor in human breast cancer

For the purpose of demonstrating the relationship between epidermal growth factor receptor (EGFR) content in the tumor and histopathologic characteristics, 45 women with breast cancer who underwent mastectomy were analyzed. EGFR content was measured by competitive binding assay using 125I, while EGFR was detected by immunocytochemical staining. Tumors with more than 1 fmol/mg protein EGFR were defined as positive, and a good correlation between competitive binding assay and staining was observed. Seventeen of them (37.8%) had EGFR-positive tumors. Eight of the 17 EGFR-positive tumors (47.1%) were positive for estrogen receptor (ER), whereas 24 of the 28 EGFR-negative tumors (85.7%) were ER-positive. This inverse relation was statistically significant (chi 2; p less than 0.05). Twelve of the 17 EGFR-positive cases (70.6%) had axillary node involvements, against 11 of the 28 (39.3%) in the EGFR-negative cases. There was no difference in the size of primary tumor between the two groups. These results suggested that EGFR-positive tumors have more malignant potency than EGFR-negative tumors. In 8 cases, EGFR content in metastatic axillary nodes was compared with that in primary tumors. More EGFR content indicated in metastatic axillary nodes than in primary tumors without significant difference.     

erbB家族在肝细胞癌中的表达及临床意义

目的:探讨erbB家族在肝细胞癌(HCC)组织中的表达及其意义.方法:采用免疫组化SP法检测55例HCC患者癌组织及癌旁组织中erbB家族中表皮生长因子受体(EGFR)、C-erbB-2、C-erbB-3、C-erbB-4的表达情况.结果:55例HCC患者癌组织及癌旁组织中,EGFR阳性表达率分别为58.18%(32/55)和36.36%(20/55),两者差异有显著性(P＜0.05);C-erbB-4阳性表达率分别为47.27%(26/55)和72.73%(40/55),两者差异有显著性(P＜0.05);而C-erbB-2、C-erbB-3在癌组织及癌旁组织中阳性表达率差异无显著性(P＞0.05).EGFR在HCC组织中的阳性表达率与临床分期、门静脉癌栓、肝外转移、术后复发等有关,C-erbB-2、C-erbB-3、C-erbB-4阳性表达率与各临床病理参数无关.结论:EGFR与肝癌的发生、发展有关,可作为HCC预后不良的参考指标;C-erbB-2及C-erbB-3可能与肝癌的发生、发展无关,而C-erbB-4低表达可能与HCC的发生有关.     

Impact of bevacizumab in combination with erlotinib on EGFR‐mutated non–small cell lung cancer xenograft models with T790M mutation or MET amplification

Erlotinib (ERL), an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, shows notable efficacy against non–small cell lung cancer (NSCLC) harboring EGFR mutations. Bevacizumab (BEV), a humanized monoclonal antibody to vascular endothelial cell growth factor (VEGF), in combination with ERL (BEV+ERL) significantly extended progression‐free survival in patients with EGFR‐mutated NSCLC compared with ERL alone. However, the efficacy of BEV+ERL against EGFR‐mutated NSCLC harboring T790M mutation or MET amplification, is unclear. Here, we examined the antitumor activity of BEV+ERL in four xenograft models of EGFR‐mutated NSCLC (three harboring ERL resistance mutations). In the HCC827 models (exon 19 deletion: DEL), ERL significantly inhibited tumor growth by blocking EGFR signal transduction. Although there was no difference between ERL and BEV+ERL in maximum tumor growth inhibition, BEV+ERL significantly suppressed tumor regrowth during a drug‐cessation period. In the HCC827‐EPR model (DEL+T790M) and HCC827‐vTR model (DEL+MET amplification), ERL reduced EGFR signal transduction and showed less pronounced but still significant tumor growth inhibition than in the HCC827 model. In these models, tumor growth inhibition was significantly stronger with BEV+ERL than with each single agent. In the NCI‐H1975 model (L858R+T790M), ERL did not inhibit growth or EGFR signal transduction, and BEV+ERL did not inhibit growth more than BEV. BEV alone significantly decreased microvessel density in each tumor. In conclusion, addition of BEV to ERL did not enhance antitumor activity in primarily ERL‐resistant tumors with T790M mutation; however, BEV+ERL enhanced antitumor activity in T790M mutation‐ or MET amplification‐positive tumors as long as their growth remained significantly suppressed by ERL.     

Role of epidermal growth factor receptor expression in primary breast cancer: results of a biochemical study and an immunocytochemical study

Summary We have conducted two series of studies, a biochemical study and an immunocytochemical study, to investigate the role of epidermal growth factor receptor (EGFR) expression in primary breast cancer patients. In the biochemical study, a consecutive 115 patients were included and EGFR was measured by a competitive binding assay with multipoint Scatchard analysis. In the immunocytochemical study comprising 126 patients, EGFR status was determined by immunostaining with anti-EGFR antibody EGFR1. Several agreements were found from these two studies. EGFR status was inversely correlated with estrogen receptor (ER) status. No significant correlation was found between EGFR status and tumor size, nodal metastases, or the expression of c-erbB-2 protein. Ki-67 immunoreactivity, a cellular proliferation marker, was enhanced in EGFR positive tumors over EGFR negative tumors, suggesting a linkage of EGFR expression to cellular proliferative activity. Post-operative follow up showed that relapse-free survival for EGFR positive patients was significantly worse than that for EGFR negative patients, particularly in node-positive patients. Multivariate analysis demonstrated a significance of EGFR status as an independent prognostic indicator in primary breast cancer. The group expressing EGFR and c-erbB-2 protein indicated a particularly high risk for relapse.