E-钙粘蛋白和S100钙结合蛋白A4在乳腺癌组织中的表达及其与病理特征的关系

目的:探讨E-钙粘蛋白(E-cadherin)和S100钙结合蛋白A4(S100A4)在乳腺癌组织中的表达及其与病理特征的关系。方法:选取2010年3月-2017年12月期间梅州市人民医院收集的乳腺癌石蜡块标本50例为乳腺癌组,另选取同时期病理检查为良性肿瘤的石蜡块标本38例为对照组,应用免疫组化法检测E-cadherin和S100A4在乳腺癌组与对照组的表达情况,分析E-cadherin和S100A4与乳腺癌病理特征的关系,并采用Spearman相关性分析方法分析E-cadherin和S100A4的相关性。结果:E-cadherin在乳腺癌组中的阳性表达率低于对照组,S100A4阳性表达率高于对照组(P0.05)。E-cadherin和S100A4阳性表达率与乳腺癌患者的年龄、是否绝经及病灶直径无关(P0.05),有淋巴结转移、临床分期为Ⅲ-Ⅳ期、病理分级为Ⅲ级的乳腺癌患者中E-cadherin阳性表达率低于无淋巴结转移、临床分期为Ⅰ-Ⅱ期、病理分级为Ⅰ-Ⅱ级者,而有淋巴结转移、临床分期为Ⅲ-Ⅳ期、病理分级为Ⅲ级的乳腺癌患者中S100A4阳性表达率高于无淋巴结转移、临床分期为Ⅰ-Ⅱ期、病理分级为Ⅰ-Ⅱ级者(P0.05)。经Spearman相关性分析显示,E-cadherin阳性表达与S100A4阳性表达呈负相关(P0.05)。结论:S100A4在乳腺癌组织中呈现高表达,E-cadherin乳腺癌组织中呈现低表达,且其与患者淋巴结转移、临床分期及病理分级存在一定的相关性。     

EZH2在乳腺癌中的表达及其临床意义

目的 探讨EZH2在乳腺癌中的表达及其临床意义.方法 用免疫组化的方法研究105例乳腺癌中EZH2蛋白表达情况,并进一步探讨其与乳腺癌临床病理因素及其预后的关系.结果 EZH2蛋白在乳腺癌组织中表达明显高于乳腺良性疾病,其表达与患者年龄、肿瘤大小、TNM分期、PR和c-erbB-2表达无关(P＞0.05),与淋巴结转移、病理组织学分级、ER表达及乳腺癌预后相关(P＜0.05).EZH2蛋白表达在三阴性乳腺癌中表达明显高于非三阴性乳腺癌(P＜0.05).结论 EZH2在乳腺癌淋巴结转移及侵袭中扮演一定的角色,其与乳腺癌预后相关,与ER阴性的乳腺癌发生发展有关.     

乳腺癌中Abi1和c-Abl及WAVE 2的表达及其相互关系

目的研究乳腺癌组织中Abi1、c-Abl和WAVE2蛋白的表达及其相互关系。方法应用免疫组化SP法检测66例乳腺癌组织和24例正常乳腺组织中Abi1、c-Abl和WAVE2蛋白的表达情况。结果 1.正常乳腺组织与乳腺癌组织相比,Abi1和WAVE2蛋白表达有显著性差异(P0.05),而c-Abl蛋白表达无显著性差异(P0.05),但有定位的改变。2.Abi1强阳性率与乳腺癌的肿瘤大小、组织学分级、淋巴结转移及临床分期呈负相关性(P0.05);与患者年龄无关(P0.05)。c-Abl阳性率及WAVE2强阳性率均与乳腺癌的组织学分级、淋巴结转移及临床分期呈负相关性(P0.05);与患者年龄及肿瘤大小无关(P0.05)。3.Abi1蛋白表达与c-Abl和WAVE2蛋白表达呈正相关(P0.05)。结论乳腺癌中Abi1低表达与预后不良有关。乳腺癌中Abi1蛋白表达的变化可影响c-Abl蛋白的定位和WAVE2蛋白的表达。推测Abi1在Abl/Abi1/WAVE2通路中具有至关重要的地位。     

Livin蛋白在乳腺癌中的表达及与Bcl-2关系

目的 探讨凋亡抑制基因Livin和Bcl-2蛋白在乳腺癌组织中表达及与临床病理参数的关系.方法 应用western blot和免疫组织化学SP法检测90例乳腺癌、30例乳腺良性病变和15例乳腺癌旁组织中Livin和Bel-2蛋白的表达情况,分析两种蛋白表达的相关性.结果 Livin蛋白在乳腺癌组织中的阳性表达率及蛋白表达量明显高于癌旁组织和乳腺良性病变,差异有显著性(P＜0.05).Livin蛋白在乳腺癌中的阳性表达与肿瘤大小,组织学类型,组织学分级及淋巴结转移无关(P＞0.05),但随临床分期的增加而升高(P＜0.05);Livin和BcI-2蛋白在乳腺癌组织中的表达显著相关(P＜0.05).结论 Livin蛋白在乳腺癌组织巾表达上调,且与病理分期有关,提示Livin蛋白可通过抑制细胞凋亡促进乳腺癌的发生、发展,Livin与Bel-2蛋白可能在乳腺癌的演进中起着协同作用.     

ERK1和E-cadherin在胃腺癌中的表达及其临床病理意义

目的探讨原发性胃腺癌(gastric adenocarcinoma,GAC)组织中ERK1和E-cadherin蛋白的表达情况及其临床病理意义。方法应用免疫组织化学ElivisionTM plus法检测261例GAC组织和100例正常胃黏膜组织中ERK1和E-cadherin蛋白的表达。结果在正常胃黏膜组织中,ERK1和E-cadherin蛋白的阳性表达率分别为26.0%和100%;在GAC组中,ERK1和E-cadherin蛋白的阳性表达率分别为49.8%和41.4%,两组之间,差异有统计学意义(P0.05)。ERK1和Ecadherin蛋白的阳性表达水平在肿瘤组织的不同分化程度、淋巴结转移与否、浸润深度及临床分期等之间差异有统计学意义(全部P0.05);ERK1蛋白的阳性表达率与E-cadherin蛋白的阳性表达率呈负相关关系(P0.05)。Kaplan-Meier生存分析表明,ERK1蛋白表达阳性的患者其生存时间显著低于其阴性表达患者(P0.001);E-cadherin蛋白表达阳性的患者其生存时间显著高于其阴性表达患者(P0.001)。多因素Cox回归分析:ERK1、E-cadherin蛋白的表达水平以及TNM分期是影响GAC患者术后生存率的独立预后因素。结论 ERK1和E-cadherin蛋白的表达水平与GAC患者肿瘤组织的分化程度、浸润深度、淋巴结转移、临床分期及预后等均有关;在GAC组织中联合检测ERK1和E-cadherin对判断GAC患者淋巴结转移及预后均有重要意义。     

Fas 相关死亡结构域蛋白在乳腺癌中表达的临床病理研究

目的:探讨Fas相关死亡结构域蛋白(Fas-associated death domain protein,FADD)在乳腺癌中表达的临床病理学意义。方法:收集乳腺癌病例及相应的临床资料包括随访资料,应用免疫组织化学技术检测乳腺良性病变,有/无淋巴结转移的乳腺癌及配对淋巴结转移灶中FADD的表达,观察分析FADD表达与乳腺癌患者年龄、肿块大小、临床分期、组织学类型和分级、雌孕激素受体水平等临床病理指标间的关系。结果:免疫组化检测结果显示良性乳腺病变组中FADD的阳性表达率(85.1%,40/47)与无淋巴结转移的乳腺癌组(45.8%,38/83),伴有淋巴结转移的乳腺癌组(67.3%72/107)和淋巴结转移灶(45.8%,49/107)组织中FADD阳性表率均有显著性差异(P值分别0.001,=0.022和0.001);此外,伴有淋巴结转移的乳腺癌组中FADD阳性表达率也均与其它三组中FADD阳性表达率之间具有显著性差异(P值分别为0.003,0.001和0.022)。FADD与患者的确诊年龄(P=0.049)和淋巴结转移有显著性相关(P=0.003),与肿瘤大小、临床分期、组织学类型、组织学分级、雌孕激素受体及cerb B-2的表达情况和月经史无明显相关性(P0.05)。生存分析显示FADD阳性表达的患者较FADD阴性患者的生存期更短。结论:FADD与乳腺癌淋巴结转移和预后有关。     

CD133 蛋白在非小细胞肺癌组织中的表达及其与临床病理参数及预后的关系

目的:研究CD133蛋白在非小细胞肺癌(NSCLC)组织中的表达及其与临床病理参数及预后的关系。方法:选择2011年4月~2012年4月间我院收治的42例NSCLC的临床资料,采用免疫组织化学染色法检测癌组织和其中30例癌旁边正常组织CD133的表达,并分析其与肺癌临床病理参数及预后的关系。结果:癌症组织CD133蛋白阳性表达率为57.1%,高于癌旁边正常组织的16.7%,差异有统计学意义(P均0.05);CD133蛋白阳性表达与NSCLC患者年龄、性别以及肿瘤大小、肿瘤位置、组织学类型、组织分化程度以及不同临床分期无关(均P0.05),与淋巴结转移有关,差异有统计学意义(P0.05);CDD133阳性及阴性患者近3年生存率比较,1年生存率比较差异不显著(P0.05),2、3年生存率比较,差异显著有统计学意义(P0.05)。结论:CD133蛋白在NSCLC组织中的高表达,且与NSCLC转移及预后密切相关,对于患者临床特征及预后的关系具有重要的研究价值。     

pSTAT3和SOCS3在人乳腺癌组织中的表达及意义

目的 研究激活STAT3( pSTAT3)蛋白和SOCS3在人乳腺癌和乳腺良性病变组织中的蛋白表达及其临床意义.方法 应用免疫组织化学检测160例乳腺癌和36例乳腺良性病变组织pSTAT3和SOCS3蛋白的表达情况,分析它们与患者临床病理特征的关系.结果 人乳腺癌组织中pSTAT3和SOCS3蛋白表达阳性率分别为69.4％和40.0％,乳腺良性病变组织中pSTAT3和SOCS3蛋白表达阳性率分别为33.3％和22.2％,前者与后者相比具有统计学意义(P＜0.01和P＜0.05);乳腺癌pSTAT3蛋白表达与肿瘤的大小、淋巴结转移和临床分期均呈显著正相关(均P＜0.01),但与患者年龄、肿瘤的组织学分级、雌孕激素受体表达和c-erBb-2表达均无显著相关(均P＞0.05);SOCS3蛋白表达与肿瘤大小呈显著正相关(P＜0.05),但与患者年龄、淋巴结转移、临床分期、肿瘤的组织学分级、雌孕激素受体表达和c-erBb-2表达均无显著相关(均P＞0.05);乳腺癌pSTAT3和SOCS3表达呈显著正相关(r=0.237,P＜0.01).结论 乳腺癌pSTAT3和SOCS3表达状况与肿瘤生长、侵袭和转移等呈密切相关,提示STAT3和SOCS3可能在乳腺癌发生发展过程中发挥了重要作用.     

三阴性乳腺癌中Ki-67 的表达及其临床病理意义

目的:探讨三阴性乳腺癌中Ki-67的表达及其临床病理意义。方法:回顾性分析2010年11月1日至2015年12月31日辽宁省肿瘤医院收治的110例行乳腺癌根治术的三阴性乳腺癌患者的临床病理资料,检测其乳腺癌组织中Ki-67的表达,并分析其与患者年龄、绝经情况、组织学分型、临床分期、淋巴结转移、肿瘤大小等临床病理资料的关系。进一步采用Kaplan-Meier生存分析法绘制生存曲线,比较高表达Ki-67和低表达Ki-67患者的3年、5年生存率。结果:Ki-67在三阴性乳腺癌患者50岁以下和50岁以上相比较,差异具有统计学意义(P0.05);Ki-67在三阴性乳腺癌患者绝经情况、组织学分型、临床分期、淋巴结转移、肿瘤大小的表达相比较,差异不具有统计学意义(P0.05);高表达Ki-67组3年生存率为79.49%,5年生存率为30.77%;低Ki-67组的3年生存率为85.92%,5年生存率为46.48%;两组3年生存率相比较差异不具有统计学意义(P0.05);两组5年生存率相比较差异具有统计学意义(P0.05);两组总生存时间相比较,差异具有统计学意义(P0.05)。结论:三阴性乳腺癌中Ki-67呈高表达,可作为乳腺癌预后不良的危险因素。     

乳腺癌中WISP2的表达及与ER、PR、HER2的关系研究

目的分析人乳腺癌(breast cancer)中Wnt-1诱导分泌蛋白2(Wnt-1inducible secreted protein-2,WISP2)的表达情况,探讨WISP2在乳腺癌发生、发展的作用及对患者预后的影响,旨在寻找预测乳腺癌患者预后的新指标。方法采用免疫组织化学ElivisionTMPlus法检测87例浸润性乳腺癌、60例乳腺原位癌和20例正常乳腺组织中WISP2的表达情况。统计分析在浸润性乳腺癌中WISP2与临床病理参数、WISP2与雌激素受体(Estrogen Receptor,ER)、孕激素受体(Progesterne Receptor,PR)、原癌基因人类表皮生长因子受体2(human epidermal growth factor receptor-2,HER2)的相关性以及分析WISP2对乳腺癌患者五年生存率的影响。结果 WISP2在浸润性乳腺癌中阳性率低于在乳腺原位癌(ductal carcinoma in situ,DICS)中阳性率,同时高于其在正常乳腺组织中的阳性率,组间比较差异均有意义(P0.05)。在浸润性乳腺癌中,无淋巴结转移组的WISP2蛋白表达高于有淋巴结组(P0.05));临床分期Ⅰ、Ⅱ期组的WISP2蛋白表达高于Ⅲ、Ⅳ期组(P0.05);随着肿瘤体积增大,WISP2的蛋白表达降低(P0.05);肿瘤组织分级越高,WISP2蛋白表达阳性率越低(P0.05)。Spearman相关性分析显示:WISP2阳性表达与ER、PR阳性表达成正相关(P0.05)。Log-rank单因素生存分析在浸润性乳腺癌中WISP2阳性组的患者五年生存率(90.9%)高于阴性组(60.5%)(P0.05)。结论 WISP2在不同乳腺组织中表达存在差异,它可能是一个保护基因,起到抑制乳腺癌患者病情进一步恶化的作用。在浸润性乳腺癌中它的表达水平可能与ER、PR表达水平有关,检测其蛋白表达情况对判断患者预后可能具有一定意义。     

E-cadherin regulates the function of the EphA2 receptor tyrosine kinase.

EphA2 is a member of the Eph family of receptor tyrosine kinases, which are increasingly understood to play critical roles in disease and development. We report here the regulation of EphA2 by E-cadherin. In nonneoplastic epithelia, EphA2 was tyrosine-phosphorylated and localized to sites of cell-cell contact. These properties required the proper expression and functioning of E-cadherin. In breast cancer cells that lack E-cadherin, the phosphotyrosine content of EphA2 was decreased, and EphA2 was redistributed into membrane ruffles. Expression of E-cadherin in metastatic cells restored a more normal pattern of EphA2 phosphorylation and localization. Activation of EphA2, either by E-cadherin expression or antibody-mediated aggregation, decreased cell-extracellular matrix adhesion and cell growth. Altogether, this demonstrates that EphA2 function is dependent on E-cadherin and suggests that loss of E-cadherin function may alter neoplastic cell growth and adhesion via effects on EphA2.     

EphA2、E-钙黏素在肿瘤中的研究

Eph受体激酶是受体酪氨酸激酶(RTKs)家族中最大的一个亚族.EphA2是Eph受体中的一员,可以调节细胞生长、迁移和血管生成.EphA2受体广泛过表达于上皮来源的肿瘤细胞,导致正常细胞恶性转化,增强肿瘤细胞的侵袭性、浸润性和转移性.E-cadherin是一种常见的上皮黏附分子,可以介导细胞之间的黏附,细胞向正常及肿瘤组织的移动并定位,同时可以影响其它蛋白的定位和转化,进一步促进肿瘤的恶型性.研究证明:许多上皮性肿瘤中,包括食管癌、宫颈癌、乳腺癌、结肠癌等都发现EphA2和E-cadherin均有异常表达,且与肿瘤的恶性程度和疾病的预后有密切的关系.本文从EphA2、E-cadherin的结构、功能、相互关系以及在肿瘤中的研究加以综述.     

Livin蛋白在乳腺癌中的表达及与Bcl-2的关系

目的 探讨凋亡抑制基因Livin和Bel-2蛋白在乳腺癌组织中表达及与临床病理参数的关系。方法应用western blot和免疫组织化学SP法检测90例乳腺癌、30例乳腺良性病变和15例乳腺癌旁组织中Livin和Bcl-2蛋白的表达情况,分析两种蛋白表达的相关性。结果Livin蛋白在乳腺癌组织中的阳性表达率及蛋白表达量明显高于癌旁组织和乳腺良性病变,差异有显著性（P〈0．05）。Livin蛋白在乳腺癌中的阳性表达与肿瘤大小,组织学类型,组织学分级及淋巴结转移无关（P〉0．05）,但随临床分期的增加而升高（P〈0．05）;Livin和Bel-2蛋白在乳腺癌组织中的表达显著相关（P〈0．05）。结论Livin蛋白在乳腺癌组织中表达上调,且与病理分期有关,提示Livin蛋白可通过抑制细胞凋亡促进乳腺癌的发生、发展,Livin与Bel-2蛋白可能在乳腺癌的演进中起着协同作用。     

E-cadherin promoter methylation can regulate its expression in invasive ductal breast cancer tissue in Chinese woman

Promoter methylation is an important mechanism of regulating E-cadherin expression. Methylation-specific PCR (MSP) assay was done to evaluate the promoter methylation status of E-cadherin gene in primary tumor samples from 23 cases of Chinese women with invasive ductal breast cancers. Western blotting assay was employed for E-cadherin and beta-actin expressions. Positive MSP results occurred in 26.1% (6/23) of primary tumor samples and none of four normal skin samples. These molecular events tended to occur in breast cancers associated with poor prognosis. Whereas the mean ratio of CDH1/beta-actin for six MSP-positive cases was 0.0290 +/- 0.0355, the mean ratio for 17 MSP-negative cases was 0.4726 +/- 0.5049 (P = 0.046). In conclusion, aberrant E-cadherin methylation preferentially occurs in invasive ductal breast cancer associated with poor prognosis and is one of the mechanisms of E-cadherin expression silence in breast cancers from Chinese women.     

Ephexin4 and EphA2 mediate cell migration through a RhoG-dependent mechanism

EphA2, a member of the Eph receptor family, is frequently overexpressed in a variety of human cancers, including breast cancers, and promotes cancer cell motility and invasion independently of its ligand ephrin stimulation. In this study, we identify Ephexin4 as a guanine nucleotide exchange factor (GEF) for RhoG that interacts with EphA2 in breast cancer cells, and knockdown and rescue experiments show that Ephexin4 acts downstream of EphA2 to promote ligand-independent breast cancer cell migration and invasion toward epidermal growth factor through activation of RhoG. The activation of RhoG recruits its effector ELMO2 and a Rac GEF Dock4 to form a complex with EphA2 at the tips of cortactin-rich protrusions in migrating breast cancer cells. In addition, the Dock4-mediated Rac activation is required for breast cancer cell migration. Our findings reveal a novel link between EphA2 and Rac activation that contributes to the cell motility and invasiveness of breast cancer cells.     

MicroRNA-335 suppresses the proliferation,migration, and invasion of breast cancer cells by targeting EphA4

MicroRNAs (miRNAs) are small noncoding RNAs that exert their functions by targeting specific mRNA sequences. Many studies have demonstrated that miRNAs are crucial for cancer progression, during which they can act as either oncogenes or tumor suppressors. Previous research has shown that miR-335 is downregulated in breast cancer, and it has been shown to be a breast cancer suppressor. In addition, emerging evidence indicates that erythropoietin-producing hepatocellular A4 (EphA4) is implicated in cancer cell proliferation, migration, and invasion. However, little is known about the relationship between miR-335 and EphA4 in breast cancer. In the present study, we used bioinformatic and biochemical analyses to demonstrate that EphA4 is a direct downstream target of miR-335 in human breast cancer MCF-7 and MDA-MB-23 cells and revealed that miR-335 negatively regulates the expression of EphA4 in these cells. Further investigation revealed that miR-335 overexpression inhibits MCF-7 and MDA-MB-231 cell proliferation and that this inhibition is attenuated by EphA4 coexpression. Similarly, miR-335 overexpression also inhibited growth and downregulated EphA4 expression in tumors in nude mice. Moreover, our results demonstrated that miR-335 overexpression suppresses migration and invasion in MCF-7 and MDA-MB-231 cells, an effect that was reversed by EphA4 overexpression. These findings confirmed that EphA4 is a direct target gene of miR-335 and that miR-335 suppresses breast cancer cell proliferation and motility in part by directly inhibiting EphA4 expression.     

EphA2: A promising therapeutic target in breast cancer

Ephrin type-A receptor 2(EphA2), a receptor tyrosine kinase, is overexpressed in human breast cancers often linked to poor patient prognosis. Accumulating evidence demonstrates that EphA2 plays important roles in several critical processes associated with malignant breast progression, such as proliferation,survival, migration, invasion, drug resistance, metastasis, and angiogenesis. As its inhibition through multiple approaches can inhibit the growth of breast cancer and restore drug sensitivity, EphA2 has become a promising therapeutic target for breast cancer treatment. Here, we summarize the expression,functions, mechanisms of action, and regulation of EphA2 in breast cancer. We also list the potential therapeutic strategies targeting EphA2. Furthermore, we discuss the future directions of studying EphA2 in breast cancer.     

凋亡抑制基因livin与survivin在乳腺癌中的表达差异

目的探讨凋亡抑制基因livin在乳腺癌发生、发展中的作用及其与survivin基因的表达和乳腺癌生物学行为之间的关系。方法采用逆转录聚合酶链反应(RT-PCR)检测44例乳腺癌组织、40例癌旁正常组织及4个乳腺癌细胞系中livinmRNA和survivin mRNA的表达,并用免疫组化(IHC)EnVision法检测上述组织和细胞中livin和survivin蛋白的表达。结果livin mRNA和survivin mRNA在乳腺癌组织中的阳性表达率分别为72.7%(32/44)和61.4%(27/44),在癌旁正常组织中的阳性率分别为7.50%(3/40)和5.00%(2/40),二者在癌组织中的表达均显著高于在正常组织中的表达(P<0.01)。livin和survivin蛋白表达情况与mRNA结果相似(P<0.01)。livin和survivin在乳腺癌组织中的表达无显著相关性(P>0.05)。4个乳腺癌细胞系中均有survivin mRNA和蛋白的表达,而MCF-7及MDA-MB-435细胞系中呈阴性表达。survivin基因在伴有淋巴结转移的乳腺癌组织中的表达明显高于无淋巴结转移的乳腺癌组织(P=0.0047),livin在雌激素受体(ER)阴性或者Her2/neu阳性表达的乳腺癌中的阳性率有升高的趋势,但并无显著性差异(P>0.05)。结论livin和survivin基因在人乳腺癌组织中表达上调,提示其可能在乳腺癌发生、发展中起重要促进作用,sur-vivin和淋巴结转移的密切关系表明它的高表达可能反映患者较差的预后。livin和survivin基因一样可能成为乳腺癌治疗中的一个靶基因。     

TGF-β1对乳腺癌细胞系Snail表达的影响

目的通过TGF-β1诱导乳腺癌MCF-7发生上皮-间质转化(epithelial-mesenchymal transition,EMT)后检测锌指转录因子Snail表达的改变,探讨Snail在EMT及乳腺癌发生发展中的作用。方法常规培养乳腺癌细胞株MCF-7后,用TGF-β1诱导其发生EMT,用Transwell侵袭小室法进行细胞体外侵袭能力检测;用免疫组织化学方法及免疫荧光检测E-cadherin、Vi mentin、Snail的表达;用real ti me PCR检测E-cadherin、Vi mentin、Snail mRNA的表达。结果TGF-β1处理72h后的MCF-7细胞穿透能力明显增强。E-cadherin蛋白及mRNA表达减少,Vi mentin、Snail蛋白及mRNA表达增加。结论E-cadherin、Vi mentin是细胞发生EMT的重要生物学标志,Snail可能在转录水平上调控E-cadherin、Vi mentin蛋白的表达,Snail在EMT和乳腺癌的发生发展中起着重要的作用。     

Eph receptor A10 has a potential as a target for a prostate cancer therapy

We recently identified Eph receptor A10 (EphA10) as a novel breast cancer-specific protein. Moreover, we also showed that an in-house developed anti-EphA10 monoclonal antibody (mAb) significantly inhibited proliferation of breast cancer cells, suggesting EphA10 as a promising target for breast cancer therapy. However, the only other known report for EphA10 was its expression in the testis at the mRNA level. Therefore, the potency of EphA10 as a drug target against cancers other than the breast is not known. The expression of EphA10 in a wide variety of cancer cells was studied and the potential of EphA10 as a drug target was evaluated. Screening of EphA10 mRNA expression showed that EphA10 was overexpressed in breast cancer cell lines as well as in prostate and colon cancer cell lines. Thus, we focused on prostate cancers in which EphA10 expression was equivalent to that in breast cancers. As a result, EphA10 expression was clearly shown in clinical prostate tumor tissues as well as in cell lines at the mRNA and protein levels. In order to evaluate the potential of EphA10 as a drug target, we analyzed complement-dependent cytotoxicity effects of anti-EphA10 mAb and found that significant cytotoxicity was mediated by the expression of EphA10. Therefore, the idea was conceived that the overexpression of EphA10 in prostate cancers might have a potential as a target for prostate cancer therapy, and formed the basis for the studies reported here.