子宫内膜癌组织中PTEN基因突变及蛋白表达的检测

背景与目的:肿瘤抑制基因———第10染色体同源丢失性磷酸酶-张力蛋白基因(phosphataseandtensinhomologdeletedonchromosometen,PTEN)被称为子宫内膜的看家基因。但有关PTEN基因在子宫内膜癌发生发展中的确切作用尚不清楚。本研究旨在检测子宫内膜癌组织中PTEN基因的突变及蛋白表达情况。方法:应用聚合酶链反应-单链构象多态性分析(polymerasechainreaction-singlestranconformationpolymorphism,PCR-SSCP)和DNA序列分析法,检测52例子宫内膜癌组织和10例正常子宫内膜组织中PTEN基因第5和第8外显子的突变;免疫组织化学法检测PTEN蛋白的表达,并结合临床病理特征进行分析。结果:子宫内膜癌组织的PTEN基因突变率和蛋白缺失率分别为25%和60%,高于正常子宫内膜组织(0%),差异有显著性(P<0.05)。病理学分级为G1、G2及肌层浸润深度<1/2的组织的PTEN基因突变率高于病理学分级为G3及肌层浸润深度≥1/2者,而病理学分级为G1、G2组织的PTEN蛋白表达缺失率低于病理学分级为G3者,差异有显著性(P<0.05)。PTEN基因突变率和蛋白表达缺失率在子宫内膜样腺癌和其它组织类型之间比较,差异有显著性(P<0.05),而在不同手术分期之间差异无显著性(P>0.05)。结论:PTEN基因突变和蛋白阳性表达常发生在病理学分级较低的子宫内膜癌病例     

c-erbB-2基因在子宫内膜癌组织中的表达及临床意义

[目的]探讨c-erbB-2在子宫内膜癌中表达及临床意义.[方法]采用免疫组化法检测子宫内膜癌、子宫内膜不典型增生和正常子宫内膜组织中c-erbB-2基因的表达,并分析其与临床病理的相关性.[结果]c-erbB-2基因的阳性表达率在子宫内膜癌组(34.62%)明显高于正常子宫内膜(11.11%)和子宫内膜不典型增生组织(13.79%)(P<0.05),并与子宫内膜癌的病理分级、临床分期、肌层浸润深度和淋巴转移明显相关(P<0.05),但与增生的程度无关(P0.05).[结论]c-erbB-2基因表达与子宫内膜癌的浸润、转移密切相关,可作为判断子宫内膜癌生物学行为及预后的重要参考指标.     

子宫内膜癌及其癌前病变组织中PTEN基因突变的研究

目的:研究抑癌基因PTEN在子宫内膜癌及其癌前病变组织中的突变,并探讨其与子宫内膜癌发生发展的关系。方法:应用聚合酶链反应-单链构象多态性分析(PCR-SSCP)方法检测60例子宫内膜癌、32例子宫内膜癌前病变(复杂型增生12例和不典型增生20例)和20例正常子宫内膜癌组织中PTEN基因的突变情况。结果:子宫内膜癌、子宫内膜癌前病变和正常子宫内膜组织中PTEN基因的突变率分别为36·67%(22/60)、9·38%(3/32)和0(0/20),三者之间差异有统计学意义,P<0·05。统计分析表明PTEN基因突变与子宫内膜癌的组织学分级、组织病理类型和肌层浸润深度有关,P<0·05。子宫内膜癌组织中,PTEN基因突变率在G1~G2级、浅肌层浸润分别高于G3级、深肌层浸润的子宫内膜癌。结论:PTEN基因突变主要发生在组织学分化好、肌层浸润浅的子宫内膜癌中。PTEN基因突变可能是子宫内膜癌发生过程中的早期分子事件。     

子宫内膜癌中诱导型一氧化氮合酶表达及与肿瘤血管形成关系

[目的]探讨诱导型一氧化氮合酶(induciblenitricoxidesynthase,iNOS)在子宫内膜癌组织中表达及与肿瘤血管形成的关系。[方法]采用免疫组化S-P法检测30例子宫内膜癌组织中iNOS和血管内皮生长因子(vascularendothelialgrowthfactor,VEGF)的表达和微血管密度(microvesseldensity,MVD)。[结果]iNOS在30例子宫内膜癌组织中的阳性表达率为73.3%;而对照组正常子宫内膜均未见表达。子宫肌层浸润深度>1/2的iNOS表达明显高于肌层未受累或≤1/2的患者(100%vs57.9%,P<0.05)。iNOS表达阳性组和阴性组MVD均值分别为45.6±3.5和20.8±4.5,两组比较差异有显著性(P<0.01)。iNOS的表达与VEGF及MVD均呈正相关(r=0.95,P<0.01;r=0.25,P<0.01)。[结论]iNOS在子宫内膜癌组织中的高表达与肿瘤血管形成及子宫肌层浸润程度的密切相关性,提示iNOS的高表达可能参与诱导肿瘤血管的形成。     

Maspin与EGFR在胃癌中的表达及临床意义

[目的]探讨Maspin与EGFR在胃癌组织中的表达及临床意义。[方法]采用免疫组化技术检测63例胃癌术后和20例正常胃组织的石蜡标本中Maspin与EGFR的表达水平,结合患者临床及病理特征进行相关性分析。[结果 ]Maspin、EGFR在胃癌组织中的阳性表达率分别为47.6%和84.1%,在对照组中为85.0%和0,两组之间有显著性差异(P<0.05)。Maspin、EGFR与肿瘤的浸润深度、淋巴结转移及临床分期相关(P<0.05),而与患者的性别、年龄、肿瘤大小、发生部位无关;另外,高中分化的胃癌组织中Maspin的阳性表达率(18/26)显著高于低分化组(69.2%vs.32.4%),而EGFR的表达与患者病理分化程度无明显关系。经Spearman等级相关检验分析,Maspin蛋白与EGFR的表达存在负相关。[结论]同时检测胃癌组织中Maspin与EGFR表达水平,对判断胃癌浸润转移潜能有一定参考价值。     

子宫内膜癌组织中抑癌基因PTEN突变分析

目的了解子宫内膜癌组织中磷酸酶基因PTEN突变情况及其与临床病理特征的关系.方法采用聚合酶链反应-单链构象多态性方法(PCR-SSCP)对70例子宫内膜癌组织进行PTEN基因9个外显子的突变检测.结果70例子宫内膜癌组织中PTEN基因突变率为38.57%(27/70),突变较多地分布在第5、7、8号外显子上;子宫内膜样癌突变率(44.8%)明显高于浆液性和粘液性腺癌(8.3%),P＜0.05,G1级、G2级、G3级的突变率分别为53.3%、45.5%、18.2%(P＜0.05),Ⅰ期、Ⅱ期、Ⅲ～Ⅳ期的突变率分别为52.4%、28.6%、14.3%(P＜0.05),肌层浸润程度越深,突变率越低(P＜0.05).结论PTEN基因突变是子宫内膜癌发生的早期事件,并与预后良好的临床病理特点相关.     

KAI1/CD82和E-cadherin在子宫内膜癌的表达

[目的]研究KAI1/CD82与E-cadherin在子宫内膜癌组织中的表达及其与临床病理参数的关系。[方法]采用免疫组织化学EnVision二步法检测76例子宫内膜癌,15例非典型增生子宫内膜和20例正常增生期子宫内膜组织中KAI1/CD82、E-cadherin的表达。[结果]KAI1/CD82在正常增生期子宫内膜、非典型增生内膜、子宫内膜癌的阳性表达率分别为95%、93.3%和60.5%;E-cadherin在正常增生期子宫内膜、非典型增生内膜、子宫内膜癌的异常表达率分别为0、6.67%和55.26%。KAI1/CD82在子宫内膜癌的表达与组织学分级、肌层浸润程度呈负相关(P=0.000,P=0.01)。E-cadherin在子宫内膜癌的表达与组织学分级及组织学类型有关。KAI1/CD82与E-cadherin在子宫内膜癌中的表达呈显著性相关(P<0.01)。[结论]KAI1/CD82表达下调和E-cadherin异常表达增高与子宫内膜癌的进展有关。     

EGFR-TKI靶向治疗EGFR 19或21突变的非小细胞肺癌临床分析

[目的]探讨表皮生长因子受体酪氨酸激酶抑制剂(EGFR-TKI)对于EGFR活化突变(外显子19缺失或外显子21点突变)的非小细胞肺癌(NSCLC)患者的临床效果。[方法]回顾性分析2013年1月至2017年12月在我院接受EGFR-TKI治疗的363例NSCLC患者。其中184例外显子19缺失,179例外显子21 L858R位点突变。[结果]与EGFR外显子21 L858R位点突变组比,EGFR外显子19缺失组的OS明显增加(92个月vs. 65个月,P<0.001)。两组中位PFS无统计学差异(12个月vs. 14个月,P>0.05)。与EGFR外显子21 L858R位点突变患者比,EGFR外显子19缺失组的客观缓解率增加(28.35%vs. 22.87%),疾病控制率增加(93.70%vs. 84.31%,P=0.014)。EGFR外显子19缺失组的患者人群中,接受EGFR-TKI治疗的患者表现出较高客观缓解率和疾病控制率,18例患者中有16例达到稳定疾病。[结论] EGFR活化突变的NSCLC患者手术后接受EGFR-TKI治疗安全有效。外显子19缺失的患者比外显子21 LS58R位点突变的患者疗效更优。     

50例子宫内膜癌Survivin表达分析

[目的]探讨survivin表达异常在子宫内膜癌的形成与侵袭和转移中的作用。[方法]采用RT-PCR、Westernblotting技术对50例子宫内膜癌组织及其相应正常内膜组织进行survivinmRNA及蛋白质表达的检测。[结果]SurvivinmRNA在子宫内膜癌中的表达明显高于正常内膜组织(P<0.05)。在手术分期为Ⅲ期患者的表达水平显著高于Ⅰ、Ⅱ期患者(P<0.05),并随着期别的升高,表达水平升高。在浅肌层的表达明显低于其它病理分期组(P<0.05),宫颈浸润组与宫颈未浸润组无明显差别(P>0.05),淋巴结转移组明显高于淋巴结未转移组(P<0.05),G3组明显高于G1、G2组(P<0.05)。Survivin蛋白质的表达情况基本同SurvivinmRNA。[结论]Survivin高表达与子宫内膜癌的发生及侵袭转移有关。     

MTA2、PGK1在子宫内膜癌组织中的表达及其与肿瘤进展的关系

目的探讨子宫内膜癌组织中转移相关基因2(MTA2)、磷酸甘油酸激酶1(PGK1)的表达与肿瘤进展的关系。方法选取80例子宫内膜癌组织(癌组织)、因子宫脱垂等手术获取的正常子宫内膜组织标本40例(正常组织),采用免疫组化法检测2组标本中的MTA2蛋白、PGK1蛋白阳性表达率,分析不同国际妇产联盟(FIGO)分期、组织学分级、是否发生淋巴结转移、不同浸润深度的子宫内膜癌组织中MTA2蛋白、PGK1蛋白阳性表达率差异。结果子宫内膜癌组织中MTA2、PGK1蛋白阳性表达率分别为71.25%、65.00%,正常子宫内膜组织中的MTA2、PGK1蛋白阳性表达率分别为25.00%、32.50%,2组有统计学差异(P<0.05);在不同FIGO分期、不同组织学分级、是否发生淋巴结转移、不同肌层浸润深度的子宫内膜癌患者MTA2蛋白阳性表达率差异无统计学意义(P>0.05);在不同FIGO分期、不同组织学分级、是否发生淋巴结转移的子宫内膜癌患者PGK1蛋白阳性表达率比较,差异均具有统计学意义(P<0.05);不同肌层浸润深度的子宫癌患者PGK1蛋白阳性表达率差异无统计学意义(P>0.05)。结论MTA2、PGK1在子宫内膜癌组织中表达上调,PGK1蛋白与肿瘤的发展关系密切。     

Occupy EGFR

Erlotinib and gefitinib inhibit the growth of non-small cell lung cancer tumors that harbor activating epidermal growth factor receptor (EGFR) mutations but are ineffective against EGFR variants found in glioblastoma. New studies by Barkovich and colleagues and Vivanco and colleagues show that these drugs only occupy the active sites of glioblastoma-derived EGFR mutants to a limited extent and fail to inhibit the activated receptor. Other EGFR inhibitors that target distinct receptor conformations are more effective in the treatment of glioblastoma. These studies reveal distinct drug selectivities for different EGFR mutations and show that an analysis of binding-site occupancy should be considered as a biomarker for inhibitor efficacy in targeting EGFR.     

Brk/PTK6 sustains activated EGFR signaling through inhibiting EGFR degradation and transactivating EGFR

Epidermal growth factor receptor (EGFR)-mediated cell signaling is critical for mammary epithelial cell growth and survival; however, targeting EGFR has shown no or only minimal therapeutic benefit in patients with breast cancer. Here, we report a novel regulatory mechanism of EGFR signaling that may explain the low response rates. We found that breast tumor kinase (Brk)/protein-tyrosine kinase 6 (PTK6), a nonreceptor protein-tyrosine kinase highly expressed in most human breast tumors, interacted with EGFR and sustained ligand-induced EGFR signaling. We demonstrate that Brk inhibits ligand-induced EGFR degradation through uncoupling activated EGFR from casitas B-lineage lymphoma-mediated EGFR ubiquitination. In addition, upon activation by EGFR, Brk directly phosphorylated Y845 in the EGFR kinase domain, thereby further potentiating EGFR kinase activity. Experimental elevation of Brk conferred resistance of breast cancer cells to cetuximab (an EGFR-blocking antibody)-induced inhibition of cell signaling and proliferation, whereas knockdown of Brk sensitized the cells to cetuximab by inducing apoptosis. Our findings reveal a previously unknown role of Brk in EGFR-targeted therapy.     

Rolling-translated EGFR variants sustain EGFR signaling and promote glioblastoma tumorigenicity

Background Aberrant epidermal growth factor receptor (EGFR) activation is observed in over 50% of cases of adult glioblastoma (GBM). Nevertheless, EGFR antibodies are ineffective in clinical GBM treatment, suggesting the existence of redundant EGFR activation mechanisms. Whether circular RNA (circRNA) encodes a protein involved in EGFR-driven GBM remains unclear. We reported an unexpected mechanism in which circular EGFR RNA (circ-EGFR) encodes a novel EGFR variant to sustained EGFR activation.Method We used RNA-seq, Northern blot, and Sanger sequencing to confirm the existence of circ-EGFR. Antibodies and a liquid chromatograph tandem mass spectrometer were used to identify circ-EGFR protein products. Lentivirus-transfected stable cell lines were used to assess the biological functions of the novel protein in vitro and in vivo. Clinical implications of circ-EGFR were assessed using 97 pathologically diagnosed GBM patient samples.Results The infinite open reading frame (iORF) in circ-EGFR translated repeating amino acid sequences via rolling translation and programmed −1 ribosomal frameshifting (-1PRF) induced out-of-frame stop codon (OSC), forming a polymetric novel protein-complex, which we termed rolling-translated EGFR (rtEGFR). rtEGFR directly interacted with EGFR, maintained EGFR membrane localization and attenuated EGFR endocytosis and degradation. Importantly, circ-EGFR levels correlated with the EGFR signature and predicted the poor prognosis of GBM patients. Deprivation of rtEGFR in brain tumor-initiating cells (BTICs) attenuated tumorigenicity and enhanced the anti-GBM effect.Conclusion Our findings identified the endogenous rolling-translated protein and provided strong clinical evidence that targeting rtEGFR could improve the efficiency of EGFR-targeting therapies in GBM.     

EGFR and cancer prognosis

Elevated levels of the epidermal growth factor receptor (EGFR), a growth-factor-receptor tyrosine kinase, and/or its cognate ligands have been identified as a common component of multiple cancer types and appear to promote solid tumour growth. This article examines the relationship between EGFR expression and cancer prognosis based on literature compiled on PubMed between 1985 and September 2000. More than 200 studies were identified that analysed relapse-free-interval or survival data directly in relation to EGFR levels in over 20000 patients. Analysis of the data showed that 10 cancer types both express elevated levels of EGFR relative to normal tissues and have been studied in sufficient depth to allow sound judgements to be made concerning the association between EGFR and patient outlook. The EGFR was found to act as a strong prognostic indicator in head and neck, ovarian, cervical, bladder and oesophageal cancers. In these cancers, increased EGFR expression was associated with reduced recurrence-free or overall survival rates in 70% (52/74) of studies. In gastric, breast, endometrial and colorectal cancers, the EGFR provided more modest prognostic information, correlating to poor survival rates in 52% (13/25) of studies, while in non-small cell lung cancer (NSCLC), EGFR expression only rarely (3/10 studies) related to patient outlook. However, it is likely that the true prognostic significance of the EGFR has been underestimated as the published studies only assessed total cellular EGFR levels, rather than the activated form of the receptor, and were not standardised with regard to patient populations or assay methods. Finally, it is important to stress that failure to detect a prognostic significance for EGFR in any one cancer type does not necessarily preclude patients from benefiting from anti-EGFR therapies.     

表皮生长因子受体与肿瘤治疗

表皮生长因子受体(EGFR)是一个家族,在不同肿瘤中均有高表达.EGFR活化会增加肿瘤细胞的增殖、侵袭、转移,因此EGFR的抑制剂成为重要的治疗肿瘤新药,EGFR成为治疗肿瘤的分子靶区.EGFR抑制剂包括小分子化合物和单克隆抗休两大类,临床试验表明在肿瘤治疗上两者都有很大价值.     

EGFR–Co-Mutated Advanced NSCLC and Response to EGFR Tyrosine Kinase Inhibitors

ObjectivesThe evolution of EGFR tyrosine kinase inhibitors (TKIs) has changed the landscape of disease for a subset of patients with NSCLC. Most patients with an EGFR mutation respond to these drugs; however, a proportion show limited or no tumor response. We explored the impact of co-mutation (double or multiple mutation), compared with a single mutation, of the EGFR gene on response to TKIs in a series of patients with metastatic NSCLC.MethodsWe retrospectively analyzed the mutation profiles of nonsquamous NSCLC tested at Royal Prince Alfred Hospital between 2012 and 2015 by MassArray using the OncoCarta v1.0 panel. Patients with metastatic disease whose tumors had sensitizing EGFR mutation(s) were included. The primary end point was progression-free survival (PFS). We used the Kaplan-Meier method for PFS and overall survival; the log rank test was used to compare groups with and without co-mutation. Multivariable analysis was done for PFS; response rate was assessed using chi-square and logistic regression analysis.ResultsA total of 62 patients were included, and of these, eight (12.9%) had a co-mutation. The median PFS and overall survival times were 11.5 and 26.3 months, respectively. Patients with EGFR co-mutation had a significantly shorter median PFS than those with a single mutation (5.7 months versus 12.3 months, p = 0.02). The response rate to TKIs was significantly worse in those with co-mutation compared with in those without co-mutation (38% versus 89%, p < 0.001).ConclusionsTaking into account the small number of patients in this study, PFS in patients with EGFR co-mutation appeared significantly shorter, and response rate significantly lower, than in patients with a single mutation. Data from multipanel testing may identify subgroups of patients who are likely to respond poorly to standard treatment. Clarification of these subgroups may improve patient care.     

EGFR过表达和EGFR基因扩增与胶质母细胞瘤预后关系的Meta分析

目的:探讨表皮生长因子受体(EGFR)过表达和EGFR基因扩增对胶质母细胞瘤(GBM)预后的影响.方法:以相对危险比(RH)为效应统计量,应用Meta分析方法对有关EGFR过表达和EGFR扩增与GBM预后的文献进行定量综合分析.结果:纳入的12篇文献.研究EGFR过表达的文献7篇,累计病例626例,阳性率为52.9%;研究EGFR扩增的6篇,累计病例433例,阳性率为33.5%.EGFR过表达与GBM预后关系的合并相对危险比(RH)及95%可信区间(CI)分别为1.06和0.73～1.53;EGFR扩增与GBM预后关系的合并RH及95%C1分别为1.11和0.81～1.53.结论:EGFR过表达和EGFR扩增可能均与GBM预后无关.     

EGFR endocytosis is a novel therapeutic target in lung cancer with wild-type EGFR

Oncogenic alterations of epidermal growth factor receptor (EGFR) signaling are frequently observed in lung cancer patients with worse differentiation and poor prognosis. However, the therapeutic efficacy of EGFR-tyrosine kinase inhibitors (TKIs) is currently limited in selected patients with EGFR mutations. Therefore, in this study, we investigated the potential molecular mechanism that contributes to cell viability and the response of gefitinib, one of the EGFR-TKIs, in lung cancer models with wide-type EGFR (wtEGFR). Interestingly, we found that EGF-induced EGFR endocytosis is existed differently between gefitinib-sensitive and -insensitive lung cancer cell lines. Suppressing EGFR endocytos decreased cell viability and increased apoptotic cell death in gefitinib-insensitive lung cancer with wtEGFR in vitro and in vivo. In addition, we found that Rab25 was differentially expressed in between gefitinib-sensitive and -insensitive lung cancer cells. Rab25 knockdown caused the changed EGFR endocytosis and reverted the gefitinib response in gefitinib-sensitive lung cancer with wtEGFR in vitro and in vivo. Taken together, our findings suggest a novel insight that EGFR endocytosis is a rational therapeutic target in lung cancer with wtEGFR, in which the combined efficacy with gefitinib is expected. Furthermore, we demonstrated that Rab25 plays an important role in EGFR endocytosis and gefitinib therapy.