胃癌组织中Bmi-1基因表达的研究

目的：多梳基因家族的Bmi．1被认为是一种癌基因,在多种肿瘤组织中均有表达。本研究主要是检测Bmi-1基因在胃癌组织中的表达及探讨其临床意义。方法：应用RT—PCR和Westernblotting方法检测45例胃癌中Bmi-1基因的表达情况,并结合患者的临床病理资料分析与其相关性。结果：Bmi-1基因阳性表达率在胃癌中为88．9％（40／45）,癌旁组织为17．7％（8／45）,差异有显著性（P〈0．05）;Bmi-1基因阳性表达率与患者年龄、性别、肿瘤大小及有无淋巴结转移无关,与肿瘤分化程度及TNM分期有关（P〈0．05）。结论：Bmi-1基因在胃癌中高表达,与胃癌的疾病进展密切相关,检测Bmi-1的表达可作为胃癌生物学行为的一项评估指标。     

Bmi-1 在非小细胞肺癌中的表达及相关性探讨

目的:探讨Bmi-1在非小细胞肺癌(NSCLC)组织中的表达及其与临床病理特征的关系。方法:采用RT-PCR检测30例非小细胞肺癌及20例癌旁组织中Bmi-1mRNA的表达情况,同时应用免疫组织化学SP法检测52例非小细胞肺癌及30例癌旁组织中Bmi-1蛋白表达情况。结果:非小细胞肺癌组织中Bmi-1mRNA表达量明显高于癌旁组织(t=5.188,P<0.01)。肺癌组中Bmi-1蛋白的阳性表达率为67.3%(35/52),明显高于癌旁组13.3%(4/30),且表达量差别有高度统计学意义(Z=-4.837,P<0.01);肺癌组中Bmi-1蛋白阳性表达与癌组织的TNM分期及有无淋巴结转移有关(Z=-2.567,-2.366,P<0.05),而与患者的性别、年龄、组织类型、分化程度等无关(P均>0.05);结论:Bmi-1在非小细胞肺癌中的高表达与肿瘤发生发展及转移相关,可成为早期诊断肺癌及判断转移的重要参考指标。     

胃癌组织中ENO1、M2-PK 蛋白表达及其临床意义

目的:探讨胃癌组织中烯醇化酶-α(enolase-α,ENO1)、肿瘤型丙酮酸激酶(tumor M2 pyruvate kinase,M2-PK)的表达、相互关系及临床病理学意义。方法:应用免疫组织化学SP染色方法分别对55例胃癌组织和23例胃良性病变组织切片染色,观察胃癌组织和良性病变组织ENO1、M2-PK的表达情况及分析两者临床病理关系。结果:胃癌组织中ENO1阳性表达率为67.3%(37/55),明显高于胃良性病变组30.4%(7/23)(P<0.01),其表达与胃癌分化程度、浸润深度、淋巴结转移及TNM分期均显著相关(均P<0.05)。M2-PK在胃癌组织中的阳性表达率为78.2%(43/55),明显高于胃良性病变组织39.1%(9/23)(P<0.01),其表达与胃癌分化程度、浸润深度均显著相关(均P<0.05)。胃癌组织中ENO1与M2-PK的表达呈正相关(r=0.5729,P<0.05)。结论:ENO1和M2-PK的表达上调与胃癌的发生、发展可能有关,联合检测两种蛋白在肿瘤组织中的表达,对临床判断胃癌的预后有一定的指导意义。     

EZH2在胃癌组织中的表达及与Hp-L型感染关系的探讨

目的探讨EZH2在胃癌组织中表达的意义及与幽门螺杆菌L型(Helicobacter pylori-L,Hp-L)感染的关系。方法 (1)应用免疫组织化学Elivision法和革兰染色法检测80例胃癌组织及30例癌旁组织(对照组)中EZH2蛋白的表达和Hp-L型的感染情况;(2)采用逆转录多聚酶链反应(RT-PCR)技术检测30例新鲜胃癌组织及对应切缘正常胃黏膜组织(对照组)中EZH2的mRNA表达。结果胃癌组EZH2蛋白表达的阳性率高于对照组(P<0.05),且EZH2表达水平升高与肿瘤大小、浸润深度、淋巴结转移和TNM分期有关(P<0.05),与性别、年龄无关(P>0.05);RT-PCR显示,肿瘤组织、远端正常对照组织的EZH2表达量差异明显(P<0.01)。胃癌组Hp-L型检出率78.8%(63/80)与对照组23.3%(7/30)有显著性差异(P<0.05),与免疫组化Hp-L型抗原表达率73.8%(59/80)无显著性差异(P>0.05),Hp-L检出阳性率为71.3%(57/80);癌组中Hp-L型感染阳性组的EZH2表达阳性率高于Hp-L型阴性组(P<0.05),且Hp-L型阳性率和EZH2蛋白的表达呈正相关(r=0.250,P<0.05)。结论 EZH2蛋白和mRNA在胃癌中的表达增加,且与胃癌的浸润、转移相关,其机制可能与幽门螺杆菌L型(Hp-L型)感染有关。     

TDGF-1在胃癌中表达的意义及其在上皮间质转化中的作用

探讨胚胎瘤衍生生长因子(teratocarcinoma-derived growth factor-1,TDGF-1)在胃癌中表达的临床意义及其与上皮间质转化(epithelial-mesenchymal transition,EMT)的关系.分别采用免疫组化SP法和逆转录-聚合酶连反应(RT-PCR)方法,检测胃癌组织和正常胃组织中TDGF-1、E-cadherin、Vimentin的表达情况(IHC70例;RT-PCR40例),分析TDGF-1表达与临床病理特征的关系及TDGF-1、E-cadherin、Vimentin三者表达的相关性.TDGF-1、E-cadherin、Vimentin蛋白在胃癌组织中的阳性表达率分别为70%、34.3%、52.9%,在正常胃组织中的阳性表达率分别为38.5%、94.3%、15.7%(P<0.05);TDGF-1、E-cadherin、Vimentin mRNA在胃癌组织中的阳性表达率分别为67.5%、37.5%、52.5%,在正常胃组织中的阳性表达率分别为35%、87.5%、22.5%(P<0.05);TDGF-1蛋白和mRNA的表达均与胃癌的浸润深度、淋巴结转移及TNM分期显著相关(P<0.05);TDGF-1高表达与E-cadherin表达减低显著相关(r=-0.447、P<0.05),TDGF-1高表达与Vimentin表达升高显著相关(r=0.318、P<0.05),E-cadherin表达减低与Vimentin表达升高显著相关(r=-0.283、P<0.05).TDGF-1可能通过调控E-cadherin、Vi-mentin表达促进EMT,从而在胃癌的侵袭转移中发挥重要作用.     

胃癌患者Sox2蛋白和CTHRC-1蛋白的表达与肿瘤发展密切相关

本研究选取病理科收集的自2016年1月至2016年12月的90例术后胃癌组织标本(胃癌组)、45例癌旁组织标本(对照组),采用免疫组化染色法检测两组标本中的Y框蛋白(Sox2)、胶原三股螺旋重叠蛋白-1表达,并分析其与肿瘤TNM分期、淋巴结转移、浸润深度、分化程度的关系,采用Spearman秩相关检验检测两种蛋白的相互关系,试图探讨胃癌患者癌组织中性别决定区Y框蛋白(Sox2)、胶原三股螺旋重叠蛋白-1(CTHRC-1)的表达及其相关性。研究结果表明:胃癌组的Sox2蛋白阳性表达率63.33%显著低于对照组的93.33%(p<0.05),胃癌组的CTHRC-1蛋白阳性表达率78.89%显著高于对照组的24.44%(p<0.05);胃癌组的Sox2蛋白阳性表达与胃癌的分化程度、发生淋巴结转移具有相关性(p<0.05);胃癌组的CTHRC-1蛋白阳性表达与胃癌的淋巴结转移、TNM分期、肿瘤浸润深度具有显著的相关性(p<0.05);胃癌组的Sox2蛋白与CTHRC-1蛋白呈显著的负相关表达(Spearman相关系数r=-0.322, p=0.002<0.05)。本研究的初步结论表明:胃癌组织中Sox2蛋白低表达和CTHRC-1蛋白高表达,并且与肿瘤发展密切相关,且二者表达呈负相关。     

胃癌组织中HER2 基因及p53蛋白表达及其临床意义

目的:研究胃癌组织中HER2基因及P53蛋白表达情况,分析其对临床诊疗的意义与价值。方法:选取2013年7月到2015年7月我院确诊的胃癌患者110例,检测患者胃癌组织中的HER2蛋白表达与基因扩增,及P53蛋白的表达情况,分析HER2基因扩增与P53蛋白表达与病理关系间的关系。结果:HER2基因扩增率为17.3%(19/110),HER2蛋白表达率为42.7%(47/110),P53蛋白表达率为58.2%(64/110),其中HER2蛋白表达3+、2+者HER2基因的扩增比例分别为3/4、6/9与1+表达者的3/16比较具有统计学意义(P0.05);HER2基因扩增和P53蛋白表达与胃癌淋巴结转移以及浸润程度有关(P0.05);相关性分析显示:HER2基因扩增与P53蛋白表达具有正相关关系(P0.05)。结论:胃癌组织中HER2基因扩增和P53蛋白协同表达,促进胃癌浸润和淋巴结转移,对胃癌早期诊断具有重要参考价值。     

PRRX1蛋白在乳腺癌中的表达及其临床意义

目的:探讨配对相关同源框1(PRRX1)在乳腺癌中的表达及其临床病理学意义,为乳腺癌的诊断和治疗提供参考依据。方法:收集2002~2003年湖南省肿瘤医院收治的临床资料及随访资料完整的80例乳腺癌组织标本,应用免疫组织化学技术检测乳腺癌和癌旁正常乳腺组织中PRRX1的表达,并分析PRRX1表达与乳腺癌患者临床病理特征间的关系。结果:PRRX1在80例乳腺癌中的阳性表达率是45%(36/80),在癌旁组织中的阳性表达率为12.5%(5/40),二者比较有显著性差异(P0.05)。PRRX1的阳性表达率与乳腺癌患者的年龄、组织学类型、肿瘤分化程度均无显著性相关(P0.05),而与淋巴结转移、临床分期显著相关(P0.05),淋巴结转移及Ⅲ~Ⅳ期乳腺癌患者PRRX1的阳性表达率显著高于无淋巴结转移及Ⅰ~Ⅱ期的乳腺癌患者(P0.05)。PRRX1表达阴性的乳腺癌患者5年生存率显著高于PRRX1表达阳性的乳腺癌患者(P0.05)。结论:乳腺癌中PRRX1的表达上调与其发生和恶性演进密切相关,可能作为乳腺癌诊断和预后预测的候选标志物。     

胃癌组织中程序性死亡配体-1和粘蛋白1的表达及相关性

目的探讨程序性死亡配体-1(programmed death ligand-1, PD-L1)和粘蛋白1(mucin 1, MUC1)在胃癌组织中的表达与临床病理因素间的关系以及两者间的相互关系。方法应用免疫组织化学S-P方法检测PD-L1和MUC1在120例胃癌组织和40例距癌灶边缘5cm以上的正常胃粘膜组织中的表达。结果在正常胃粘膜组织中未见PD-L1阳性免疫反应,在胃癌组织中PD-L1阳性表达率为32.5%(39/120);MUC1在正常胃粘膜组织中的阳性表达率为100%,在胃癌组织中的阳性表达率是65%(78/120)。在胃癌组织中,PD-L1和MUC1表达与肿瘤大小、肿瘤浸润深度及淋巴结转移有关,与患者年龄、性别、肿瘤分化程度及TNM分期无关;PD-L1和MUC1在胃癌组织中的表达呈正相关。结论 PD-L1和MUC1在胃癌组织中的生物学行为以及两者的相关性提示联合检测更有意义。     

HMGA2与胃癌上皮细胞间质转化的相关性及临床意义

探讨HMGA2、E-cadherin及N-cadherin在胃癌组织中差异性表达的临床意义及其与上皮细胞间质转化的关系.应用RT-PCR方法检测20例胃癌组织及对应的正常胃粘膜组织HMGA2 mRNA的表达,应用免疫组织化学法检测71例胃癌组织及癌旁组织中HMGA2、E-cadherin及N-cadherin的表达情况,与临床资料做统计学分析.HMGA2 mRNA在胃癌组织和癌旁组织中的表达存在显著性差异(P<0.01),在胃癌组织中HMGA2、E-cadherin及N-cadherin的阳性表达率分别为64.7%、29.6%和43.7%,HMGA2和E-cadherin的表达成负相关(P<0.05),和N-cadherin的表达成正相关(P<0.05),HMGA2表达和胃癌患者淋巴结转移及临床分期有显著相关性(P<0.05).HMGA2高表达的胃癌组织中有明显的上皮细胞间质转化表型,其表达与胃癌侵润转移有一定的相关性.     

Silencing of Bmi-1 gene by RNA interference enhances sensitivity to doxorubicin in breast cancer cells

The oncogene Bmi-1 is highly up-regulated in breast carcinoma and is found to be efficient in preventing apoptosis of the cancer cells. Doxorubicin is an important chemotherapeutic agent against breast carcinoma. However, the effective therapeutic response to doxorubicin is often associated with severe toxicity. The present study is targetted at developing a strategy to increase doxorubicin sensitivity to lower doses without compromising its efficacy. A stable cell line with a persistent silencing of Bmi-1 was established. MTT assay was performed to evaluate 50% inhibitory concentration (IC50) values of doxorubicin. Apoptosis was detected by FCM and the expression of related genes [phosphor-Akt (pAkt), totle-Akt (tAkt), Bcl-2 and Bax] was studied by Western blot. In vivo, the sensitivity of the tumor tissues against doxorubicin was evaluated by transplanted MCF-7 nude mice model and the apoptosis of tissue cells was detected by TUNEL assay. The expression of pAkt and Bcl-2 was down-regulated, whereas Bax was up-regulated in Bmi-1 silencing cells. The results obtained indicated that silencing of Bmi-1 can render MCF-7 cells more sensitive to doxorubicin which induced a significantly higher percentage of apoptosis cells in vitro and in vivo. All together these results clearly demonstrate that Bmi-1 siliencing combined treatment of doxorubicin might be a new strategy for biological treatment on breast cancer.     

Bmi-1基因表达在骨髓增生异常综合征中的临床意义

目的:探讨Bmi-1基因表达在骨髓增生异常综合征(MDS)中的临床意义。方法:选择2011年1月~2012年12月我院收治的MDS患者41例为研究组,另选取非恶性血液病患者20例为对照组,检测Bmi-1的表达水平,并检测其骨髓白血病干细胞免疫表型(CD34+CD38-CD123+),然后分析患者Bmi-1的表达水平与骨髓原始细胞比例及骨髓染色体核型的关系。结果:Bmi-1表达水平研究组患者明显高于对照组,且研究组中RA患者明显低于RAEB患者,但RA患者及RAEB患者均高于对照组(P0.01);Bmi-1基因高表达组白血病干细胞免疫表型CD34+CD38-CD123+/CD34+明显高于Bmi-1基因低表达组患者(P0.01);Bmi-1基因高表达组中,骨髓原始细胞5%的病例数及染色体不良核型发生率均高于低表达组。结论:Bmi-1基因的表达可以作为MDS患者在分子水平上的恶性程度标志之一。     

Efficient Immortalization of Primary Nasopharyngeal Epithelial Cells for EBV Infection Study

Nasopharyngeal carcinoma (NPC) is common among southern Chinese including the ethnic Cantonese population living in Hong Kong. Epstein-Barr virus (EBV) infection is detected in all undifferentiated type of NPC in this endemic region. Establishment of stable and latent EBV infection in premalignant nasopharyngeal epithelial cells is an early event in NPC development and may contribute to its pathogenesis. Immortalized primary nasopharyngeal epithelial cells represent an important tool for investigation of EBV infection and its tumorigenic potential in this special type of epithelial cells. However, the limited availability and small sizes of nasopharyngeal biopsies have seriously restricted the establishment of primary nasopharyngeal epithelial cells for immortalization. A reliable and effective method to immortalize primary nasopharyngeal epithelial cells will provide unrestricted materials for EBV infection studies. An earlier study has reported that Bmi-1 expression could immortalize primary nasopharyngeal epithelial cells. However, its efficiency and actions in immortalization have not been fully characterized. Our studies showed that Bmi-1 expression alone has limited ability to immortalize primary nasopharyngeal epithelial cells and additional events are often required for its immortalization action. We have identified some of the key events associated with the immortalization of primary nasopharyngeal epithelial cells. Efficient immortalization of nasopharyngeal epithelial cells could be reproducibly and efficiently achieved by the combined actions of Bmi-1 expression, activation of telomerase and silencing of p16 gene. Activation of MAPK signaling and gene expression downstream of Bmi-1 were detected in the immortalized nasopharyngeal epithelial cells and may play a role in immortalization. Furthermore, these newly immortalized nasopharyngeal epithelial cells are susceptible to EBV infection and supported a type II latent EBV infection program characteristic of EBV-infected nasopharyngeal carcinoma. The establishment of an efficient method to immortalize primary nasopharyngeal epithelial cells will facilitate the investigation into the role of EBV infection in pathogenesis of nasopharyngeal carcinoma.     

Deregulation of Bmi-1 is associated with enhanced migration,invasion and poor prognosis in salivary adenoid cystic carcinoma

Background

Bmi-1 had been found to involve in self renewal of stem cells and tumorigenesis in various malignancies. In this study, we investigated the role of Bmi-1 in the development of salivary adenoid cystic carcinoma (SACC).

Methods

At first, we confirmed that the deregulation of Bmi-1 was a frequent event in SACC; up-regulation of Bmi-1 was correlated with clinical stages, vital status and distant metastasis and associated with reduced overall survival and disease free survival. SACC-LM cells, higher migration and invasion abilities, elevated the expression of Bmi-1 protein, epithelial-mesenchymal transition (EMT) related proteins (Snail, Slug and Vimentin) and cancer stem cells (CSCs) related proteins (ABCG₂, Notch, ALDH-1, Oct-4, Nanog and Epcam) compared to the SACC-83 cells (lower migration and invasion abilities). The migration and invasion abilities were inhibited in SACC-LM cells upon Bmi-1 knockdown. Meanwhile, Bmi-1 knockdown resulted in simultaneous loss of stem cell markers and EMT markers in SACC-LM cells.

Conclusion

Our studies confirm that Bmi-1 deregulation plays an important role in the development of SACC and contributes to the migration and the invasion abilities of SACC, which is involved in EMT and CSCs.

General significance

To our knowledge, this is the first study revealing that Bmi-1 deregulation is associated with enhanced migration, invasion and poor prognosis in salivary adenoid cystic carcinoma.     

Bmi-1在非小细胞肺癌中的表达及相关性探讨

目的：探讨Bmi-1在非小细胞肺癌（NSCLC）组织中的表达及其与临床病理特征的关系。方法：采用RT-PCR检测30例非小细胞肺癌及20例癌旁组织中Bmi-1mRNA的表达情况,同时应用免疫组织化学SP法检测52例非小细胞肺癌及30例癌旁组织中Bmi-1蛋白表达情况。结果：非小细胞肺癌组织中Bmi-1mRNA表达量明显高于癌旁组织（t=5.188,P〈0.01）。肺癌组中Bmi-1蛋白的阳性表达率为67.3%（35/52）,明显高于癌旁组13.3%（4/30）,且表达量差别有高度统计学意义（Z=-4.837,P〈0.01）;肺癌组中Bmi-1蛋白阳性表达与癌组织的TNM分期及有无淋巴结转移有关（Z=-2.567,-2.366,P〈0.05）,而与患者的性别、年龄、组织类型、分化程度等无关（P均〉0.05）;结论：Bmi-1在非小细胞肺癌中的高表达与肿瘤发生发展及转移相关,可成为早期诊断肺癌及判断转移的重要参考指标。     

沉默Bmi-1基因表达稳定细胞株的建立及其生物学特性的研究

B细胞特异性莫洛尼鼠白血病病毒插入位点1(B-cell-specific moloney murine leukemia virus insertionsite 1,Bmi-1)基因是多梳基因家族成员,参与细胞增殖调控.研究发现Bmi-1基因可能参与肿瘤的形成,可能成为肿瘤潜在的治疗靶点.用RNA干扰(RNA interference,RNAi)沉默Bmi-1基因表达观察其对乳腺癌细胞株MCF-7侵袭和转移等生物学特性的影响,以探讨Bmi-1在乳腺癌发生发展中的作用.PT67细胞包装质粒后产生的逆转录病毒感染MCF-7细胞,嘌呤霉素筛选建立稳定细胞株,稳定抑制Bmi-1的细胞株命名为MCF-7/Bmi-1si.通过RT-PCR和Western blot分别从mRNA和蛋白水平检测Bmi-1的表达量;平板克隆形成实验检测细胞克隆形成能力;Transwell侵袭小室模型检测细胞体外侵袭和转移能力.MCF-7/Bmi-1si组与MCF-7和MCF-7/GFPsi组相比,Bmi-1 mRNA和蛋白表达量明显减少,克隆形成数及形成率也明显减少(P<0.05).侵袭和转移实验表明:与MCF-7和MCF-7/GFPsi组相比,MCF-7/Bmi-1si组细胞在Transwell侵袭小室中24 h穿膜细胞数明显减少(P<0.05).结果表明沉默Bmi-1基因表达稳定细胞株构建成功,Bmi-1基因表达的沉默能显著降低MCF-7细胞的体外增殖及侵袭转移能力.     

Bmi-1 confers adaptive radioresistance to KYSE-150R esophageal carcinoma cells

Radiotherapy (RT) is a major modality of cancer treatment. However, tumors often acquire radioresistance, which causes RT to fail. The exact mechanisms by which tumor cells subjected to fractionated irradiation (FIR) develop an adaptive radioresistance are largely unknown. Using the radioresistant KYSE-150R esophageal squamous cell carcinoma (ESCC) model, which was derived from KYSE-150 parental cells using FIR, the role of Bmi-1 in mediating the radioadaptive response of ESCC cells to RT was investigated. The results showed that the level of Bmi-1 expression was significantly higher in KYSE-150R cells than in the KYSE-150 parental cells. Bmi-1 depletion sensitized the KYSE-150R cells to RT mainly through the induction of apoptosis, partly through the induction of senescence. A clonogenic cell survival assay showed that Bmi-1 depletion significantly decreased the radiation survival fraction in KYSE-150R cells. Furthermore, Bmi-1 depletion increased the generation of reactive oxygen species (ROS) and the expression of oxidase genes (Lpo, Noxo1 and Alox15) in KYSE-150R cells exposed to irradiation. DNA repair capacities assessed by γ-H2AX foci formation were also impaired in the Bmi-1 down-regulated KYSE-150R cells. These results suggest that Bmi-1 plays an important role in tumor radioadaptive resistance under FIR and may be a potent molecular target for enhancing the efficacy of fractionated RT.