K-ras突变导致肺癌细胞对表皮生长因子受体抑制剂耐药的机制

目的 比较不同细胞株引入K-ras突变质粒前后对表皮生长因子受体(EGFR)信号传导通路活性的变化,探讨K-ras突变对于EGFR抑制剂耐药的机制.方法 通过噻唑蓝(MTF)比色法检测HCC827及H292细胞在转染K-ras基因前后的EGFR下游AKT及STAT通路抑制剂敏感性变化,免疫印迹法(Western blot)检测EGFR下游通路激活状态变化.结果 转染后HCC827细胞对于AKT和STAT通路抑制剂敏感性仅下降1.9和5.3倍,H292细胞对于AKT和STAT通路抑制剂敏感性仅下降3.0和2.5倍,远低于吉非替尼敏感性下降程度,转染K-ras的HCC827细胞AKT通路和STAT3通路持续激活,而转染K-ras的H292细胞AKT通路和STAT3通路的活性降低.结论 K-ras导致EGFR抑制剂耐药的原因可能还存在其他耐药机制,携带EGFR基因突变或野生型的肺癌细胞中,K-ras突变对于AKT和STAT通路的影响可能存在不同.

Abstract：

Objective By comparing the activity of signaling pathway in different cell lines affected by K-ras mutation, to investigate the resisitance to epidermal growth factor receptor (EGFR) inhibitors due to K-ras mutation. Methods Methyl thiazol tetrazolium (MTF) method was used to mensure the sensitivity and half maximal inhibitory concentration ( IC50 ) of AKT and STAT inhibitors after transfection of K-ras or blank plasmid into HCC827 and H292 cells. Western blotting was used to compare the activity of downstream signaling pathway in different cell lines. Results After transfection of mutant K-ras, the IC50 of AKT and STAT inhibitors in HCC827 cells was reduced by 1.9 and 5.3 times respectively, and that in H292 cells was reduced by 3.0 and 2. 0 times respectively. The activity of AKT and STAT pathways in HCC827 cells transfected with mutant K-ras was continuously activated, while that in H292 cells was suppressed. Conclusion K-ras-induced resistance to EGFR inhibitors may be related to other mechanisms. In the tumor cells bearing mutant or wild-type EGFR gene, there may exist different influences of K-ras mutations on AKT and STAT pathways.     

表皮生长因子受体及其在肺癌组织中的表达

表皮生长因子受体及其在肺癌组织中的表达黄云超综述杨俊杰周清华审校１９５９年Ｃｏｈｅｎ等在研究神经生长因子时以小鼠颌下腺组织中发现一种能刺激表皮细胞增生、角化的物质，命名为表皮生长因子（ＥｉｐｅｒｍａｌＧｒｏｗｔｈＦａｃｔｏｒ，ＥＧＦ）［１］。进一步研...     

非小细胞肺癌中表皮生长因子受体基因拷贝的检测及其临床意义

目的 检测国人非小细胞肺癌标本中表皮生长因子受体(EGFR)基因高拷贝的发生率及与临床特征的关系.方法 236例非小细胞肺癌标本制作成组织微阵列,使用Vysis公司的荧光原位杂交探针检测EGFR基因拷贝数.结果 193例标本得到结果 ,检测到EGFR基因高拷贝81例(占42.0%),其中42例(21.8%)为高多倍体,39例(20.2%)为基因扩增.其发生与病理、分期、性别、吸烟等临床特征无明显相关,与患者的1-3年生存率无明显相关.结论 国人肺癌中EGFR基因拷贝数的分布情况与西方人类似,与临床特征及预后无明显相关.     

肺癌中表皮生长因子受体过表达与女性、非吸烟、腺癌和基因突变的关系

目的探讨女性和非吸烟的肺腺癌标本中表皮生长因子受体（EGFR）过表达与EGFR基因突变的关系。方法应用组织微阵列和免疫组织化学方法检测137例国人非小细胞肺癌标本（鳞癌71例、腺癌66例）中EGFR的表达，采用测序的方法检测EGFR基因突变。结果EGFR过表达率在肺鳞癌中为63．4％显著高于腺癌的43．9％（P〈0．05），其与性别、吸烟情况无关，也与基因突变无关。结论EGFR的过表达率在女性、非吸烟、腺癌及存在EGFR突变的标本中未见升高，提示这些人群中EGFR抑制剂效果较好的原因与蛋白过表达无关。     

K-Ras突变对表皮生长因子受体抑制剂敏感细胞株的影响

目的 观察K-Ras突变对于携带表皮生长因子受体(EGFR)突变细胞的EGFR抑制剂敏感性的影响.方法 构建K-Ras突变真核表达质粒,采用脂质体转染技术转染肺癌细胞HCC827(EGFR突变,K-Ras野生)和H292(EGFR、K-Ras均野生),噻唑蓝(MTT)比色法测定转染K-Pas突变质粒和空白质粒后各细胞对EGFR抑制剂的半数抑制浓度(IC_(50)).结果 真核表达质粒构建成功.细胞HCC827未转染K-ras突变质粒对吉非替尼(Iressa)的IC_(50)为0.007,转染后对Iressa的IC_(50)为12.3,差异有统计学意义(P<0.01).细胞H292未转染K-ras突变质粒对Iressa的IC_(50)为0.04,转染后对Iressa的IC_(50)为12.0,差异有统计学意义(P<0.01).细胞A549(K-Ras突变)对Iressa的IC_(50)为12.8,与转染K-ras突变质粒的细胞HCC827及H292比较,差异无统计学意义(P>0.05).结论 野生型或突变型EGFR出现K-Ras突变均可引起吉非替尼耐药,其程度与K-Ras突变的细胞株相当.     

烧伤创面内表皮生长因子与表皮生长因子受体蛋白变化的临床研究

目的：观察烧伤创面内表皮生长因子（EGF）与表皮生长因子受体（EGFr）的变化,探讨表皮生长因子在创面愈合中的作用,为临床治疗提供依据。方法：应用免疫组织化学方法对35例烧伤病人创面不同部位内的EGF蛋白和EGFr蛋白的表达强度和分布情况进行了观察。结果：EGF蛋白和EGFr蛋白在烧伤创面内有明显的一致表达,在创面上皮愈合边缘部位EGF蛋白和EGFr蛋白表达最强;在创面中心肉芽部位EGF蛋白和EGFr蛋白表达次之;在创面已经愈合部位EGF蛋白和EGFr蛋白表达相对减弱;正常皮肤对照部位EGF蛋白和EGFr蛋白无明显的表达。结论：烧伤创面内不同部位EGF、EGFr蛋白的表达强度和分布情况不同,其变化与创面愈合密切相关,提示创面内源性的EGF、EGFr蛋白表达变化在促进创面愈合方面有很重要的作用。     

表皮生长因子及其受体在前列腺中作用

表皮生长因于是一种单链多肽生长因子，体外实验证明能刺激前列腺细胞增殖和分化；表皮生长因子受体是一种跨膜糖蛋白，具有酪氢酸激酶活性；前列腺组织中存在表皮生长因子及其受休，它们以自分泌和／或旁分泌方式作用于前列腺，而且与雄激素关系密切并受其调节。     

表皮生长因子受体基因突变非小细胞肺癌腹膜转移5例预后分析

目的分析表皮生长因子受体(EGFR)基因突变阳性的非小细胞肺癌(NSCLC)腹膜转移患者的预后因素。 方法收集2014—2019年收治的EGFR突变阳性NSCLC腹膜转移患者的临床资料。主要观察和分析指标为中位生存期(mOS ),其中mOS1表示从确诊不可切除的中晚期肺癌开始或根治性切除术后发生复发和/或转移开始接受一线酪氨酸激酶抑制剂(TKI)治疗至出现肿瘤耐药的时间,mOS2表示从确诊腹膜转移开始至死亡或随访终点的时间。 结果共收集5例患者,均为异时性转移,第一代TKI治疗耐药后出现腹膜转移。耐药后再次基因检测发现EGFR T790M突变阳性3例。mOS1：总体为14.4个月;EGFR 19外显子突变者为18.8个月,21外显子突变者为16.3个月,18外显子突变者为15.6个月。mOS2：总体为7.5个月;EGFR T790M突变阳性者为10.4个月,EGFR T790M突变阴性者为5.2个月;接受靶向治疗联合血管抑制剂治疗者为12.6个月,单纯靶向治疗者为9.3个月,血管抑制剂联合化学治疗者为6.2个月,单纯血管抑制剂治疗者为4.2个月。 结论EGFR突变阳性NSCLC患者腹膜转移后再次行基因检测非常必要,靶向治疗联合血管抑制剂治疗策略可能使患者获得更长的生存期。     

甲状腺癌中表皮生长因子受体的表达

为了解甲状腺中表皮生长因子受体的表达意义,应用免疫组化方法检测了８１例甲状腺癌中ＥＧＦＲ的表达,并与甲状腺腺瘤和癌旁正常甲状腺组织相比较。结果：甲状腺癌中４５例ＥＧＦＲ表达阳性,而甲状腺腺瘤及癌旁正常甲状腺组织中均未见ＥＧＦＲ表达。ＥＧＦＲ表达阳性率在甲状腺癌的病理类型,临床分期,浸润程度及淋巴结转移诸因素间接羞匀无统计学意义。     

Clinical Significance of the Epidermal Growth Factor Receptor and HER2 Receptor in Resectable Gastric Cancer

Background: Epidermal growth factor receptor (EGFR or HER1) and its homolog c-erbB-2 (HER2) are membrane receptors. Both EGFR and HER2 genes are overexpressed in a variety of solid human cancers and are related to poor prognosis of the patients. The objective of this work was to evaluate the EGFR and HER2 contents in resectable gastric cancer, their possible relationship with clinicopathologic parameters of tumors, and their prognostic significance.Methods: This was a prospective analysis of 63 patients with resectable gastric carcinomas, with a mean follow-up period of 40.7 months. Membranous EGFR levels were examined by radioligand binding assays, and cytosolic HER2 levels were examined by means of an immunoenzymatic assay.Results: There was a wide variability of EGFR (1–1,239 fmol/mg of protein) and HER2 (7–20,863 NHU/mg of protein) levels in tumors. There was no significant correlation between these levels and patient or tumor characteristics. However, high levels of EGFR and HER2 were significantly associated with a shorter overall survival period (P = .03 and P = .02, respectively).Conclusions: There is a wide variability in membranous EGFR levels and in cytosolic HER2 levels in gastric cancer, which seems to be related to the biological heterogeneity of these tumors. In addition, high tumor EGFR and HER2 levels were associated with an unfavorable outcome in patients with resectable gastric cancer.     

Elevated Serum Epidermal Growth Factor Receptor Level in Stage IV Thymoma

Using the enzyme immunoassay for epidermal growth factor receptor (EGFR), we investigated whether serum EGFR levels could be used as a predictor of the development and extension of thymoma. Serum samples were collected from 31 patients with thymoma and 16 patients with nonmalignant thoracic disease before clinical treatment. There was no difference between the serum EGFR levels of the patients with thymoma and the nonmalignant controls, being 49.1 ± 136.3 and 22.6 ± 7.3fm/ml, respectively (P = 0.11). However, patients with stage IV thymoma had significantly higher EGFR levels than those with stage I or stage II thymoma, the respective values being 127.8 ± 243.9, 10.9 ± 9.2 (P = 0.02), and 19.7 ± 10.6 (P = 0.0433) fm/ml. The serum EGFR levels were similar in the pathological subtypes. These findings suggest that serum EGFR levels may serve as a marker that could be used as a diagnostic indicator of the invasion of thymoma.     

Prognostic Significance of Epidermal Growth Factor Receptor Expression in Colon Cancer Patients Undergoing Curative Surgery

Background To investigate the role of epidermal growth factor receptor (EGFR) expression as a prognostic marker for prediction of cancer behavior and clinical outcomes in colon cancer patients undergoing potentially curative surgery. Methods EGFR determination using a commercially available immunohistochemistry kit was performed in tissues from 149 colon cancer patients receiving primary surgical treatment and in 25 normal colon mucosa specimens from noncancer patients. EGFR positivity was correlated in univariate and multivariate analyses with disease recurrence and survival. In addition, p27, p53, and vascular endothelial growth factor expression were assessed by immunohistochemistry in 104 patients and correlated with EGFR tumor expression and clinical outcome. Results EGFR expression was detected in approximately one third of colon cancer patients (53 of 149; 35.6%). In 126 curatively treated patients, EGFR expression was correlated with disease recurrence and worse survival in both univariate and multivariate analyses. In a multivariate model for predicting recurrence and survival, Dukes’ staging, p27, and EGFR expression were the only independent covariates. In particular, in Dukes’ A and B patients the 5-year survival probability was 96% for EGFR-negative and high p27 expression cases and was 30.7% for EGFR-positive and low p27 expression cases. Conclusions EGFR expression was an independent prognostic indicator of disease recurrence and poor survival in colon cancer patients undergoing curative surgery. In the context of novel therapeutic options such as molecularly targeted therapies, these findings suggest that anti-EGFR drugs could be evaluated in the adjuvant treatment of EGFR-positive colon cancer patients.     

Expression of Vascular Endothelial Growth Factor (VEGF) and Epidermal Growth Factor Receptor (EGFR) is an Independent Prognostic Indicator of Worse Outcome in Gastric Cancer Patients

BACKGROUND: Unlike other human tumors, gastric cancer remains a great therapeutic challenge since no standardized postoperative treatment exists. Knowledge of molecular pathways determining the behavior of individual gastric tumors seems to be crucial for therapeutic decisions, and evaluation of vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) expression might be critical for prognosis, assessment, and identification of patients that could be treated with tailored therapies. METHODS: VEGF and EGFR determination was performed in 88 gastric cancer samples as well as 25 normal gastric mucosa specimens from non-cancer patients using a commercially available immunohistochemistry kit. In all samples, the correlation of VEGF and EGFR expression was investigated with each other, and with other prognostic indicators in all samples, and, finally, with survival rates in 69 patients undergoing potentially curative surgery. RESULTS: Forty-eight per cent (42 cases) of gastric cancers expressed VEGF, and 44% (39 cases) stained for EGFR. In curatively treated patients, VEGF and EGFR expression was demonstrated to correlate with worse survival in both univariate and multivariate analyses. Molecular profiling was shown to more accurately estimate the risk of cancer-related death than TNM stage, and, of most interest, to allow sorting out high-risk patients within the same stage. CONCLUSIONS: These findings provide evidence that contemporary evaluation of VEGF and EGFR expression may be crucial to select gastric cancer patients with poor prognosis who may benefit of tailored treatments.     

膜表面核仁素参与表皮生长因子受体信号启动的研究

目的探讨膜表面核仁素（nucleiolin,NCL）在表皮生长因子受体（epidermal growth factor receptor,EGFR）信号启动中的作用。方法采用免疫组化法检测NCL及EGFR在甲状腺乳头状癌组织中的表达;Western blot法检测甲状腺乳头状癌细胞TPC-1中磷酸化EGFR（phosphorylation EGFR,p-EGFR）的表达水平;Transwell小室试验检测TPC-1细胞的迁移能力。结果免疫组化染色结果显示,甲状腺乳头状癌组织中NCL及EGFR的表达阳性率分别为100％（56／56）和80.4％（45／56）;NCL及EGFR的表达与淋巴结转移有关（P〈0.05）,且NCL的表达与EGFR的表达呈正相关关系（r=0.635,P〈0.01）。Western blot法检测结果显示,拮抗甲状腺乳头状癌TPC-1细胞的NCL或EGFR后,其p-EGFR表达水平均明显下调（P〈0.01）。Transwell小室试验发现,拮抗NCL和EGFR后,可明显减少TPC-1细胞的穿膜细胞数（P〈0.01）。结论膜表面NCL可能是EGFR受体信号启动的必要成分,可能通过EGFR参与肿瘤的生长与转移。以NCL为靶点将开拓肿瘤新的治疗领域。     

Epidermal Growth Factor Receptor Expression in Spindle Cell Carcinomas of the Head and Neck

Spindle cell carcinoma (SpCC) is an uncommon head and neck squamous cell carcinoma (SCC) variant consisting of spindled and/or pleomorphic cells with epithelial differentiation. Epidermal growth factor receptor (EGFR) is expressed by >90 % of conventional SCC, and high level expression is associated with a poorer prognosis. Anti-EGFR therapies are commonly used to treat head and neck SCC. However, no studies have evaluated EGFR expression in SpCC. Cases of SpCC were retrieved from department files. The diagnosis required either a biphasic lesion with a squamous neoplastic component, or a purely spindle cell or pleomorphic tumor with immunohistochemical positivity for epithelial markers. EGFR immunohistochemistry was performed and was quantified in quartiles. Medical records were reviewed for clinical follow up information. EGFR was expressed in 21/30 (70 %) cases, including in the squamous component in 18/19 (95 %) and the spindle cell component in only 12/30 (40 %). Where the spindle cell component was positive, the intensity and distribution were lower than for the squamous component. Recurrent tumors were predominantly (80–90 %) of the spindle cell component, and had low (or absent) EGFR expression. Kaplan–Meier survival analysis showed no statistically significant differences in overall or disease free survival between the EGFR expressing and non-expressing groups (p = 0.414 and 0.19, respectively). SpCCs of the head and neck have a poor prognosis, and markedly reduced EGFR expression. EGFR-specific therapies may not be ideal for SpCC patients, which may lack EGFR expression, but further studies are needed.

Electronic supplementary material

The online version of this article (doi:10.1007/s12105-014-0604-y) contains supplementary material, which is available to authorized users.     

表皮生长因子及其受体在睾丸中的分布与功能

睾丸Sertoli细胞和早期生精细胞不仅存在表皮生长因子 (EGF)而且存在EGF受体 (EGFR) ,睾丸Leydig细胞也含有EGFR。EGF通过和EGFR结合 ,发挥特定的生物学效应 ,能刺激睾丸雄激素的合成和生精细胞的成熟。但是高浓度的EGF反而会抑制生精细胞的成熟。     

腹膜透析透出液中表皮生长因子的表达及意义

目的：研究腹膜透析患透出液中表皮生长因子（EGF）的表达情况并探讨其意义。方法：检测16例腹透患血清及腹透液中的β2微球蛋白，转铁蛋白及IgG的浓度并进行线性回归分析。根据血清含量得出透出液中的EGF预测值，与实测值比较。结果：腹透透出液中EGF表达与预期值相比无差异。说明透出液中EGF均为循环转运至腹腔的结果。结论：腹透时腹腔内缺乏局部自分泌及旁分泌及旁分泌机制。这可能是腹膜间皮损伤后修复不全的重要原因。     

Down-Regulation of Osteoblastic Cell Differentiation by Epidermal Growth Factor Receptor

The role of epidermal growth factor receptors (EGF-R) in osteogenic cell differentiation was investigated using preosteoblastic MC3T3-E1 (MC3T3) cells and osteoblast-like ROS 17/2.8 (ROS) cells. When cultured in the presence of β-glycerophosphate (GP) and ascorbic acid (AA), MC3T3 cells underwent spontaneous differentiation into osteoblasts which was confirmed as they expressed osteoblast markers such as alkaline phosphatase (ALP), bone sialoprotein (BSP) and osteocalcin (OC). Interestingly, the number of EGF-binding sites decreased during their differentiation into osteoblasts, and the osteogenic protein-1 (OP-1) treatment, which accelerated their differentiation, lowered the number of EGF-binding sites even further. On the other hand, ROS cells with high expression levels of osteoblast markers and no EGF-R, after being transfected with human EGF-R cDNA (EROS cells), expressed numerous EGF-binding sites as well as EGF-R mRNA and protein; in the process, they ceased to express osteoblast markers, indicating their dedifferentiation into osteoprogenitor cells. Both MC3T3 and EROS cells showed increased cell growth in response to EGF, whereas ROS cells did not. These results imply that the EGF/EGF-R system in osteogenic cells has a crucial function in osteoblast phenotype suppression and osteogenic cell proliferation.