乳腺肿瘤组织中GATA3的表达及临床意义

目的：探讨乳腺肿瘤组织中转录因子GATA3的表达及其与临床病理特征的相关性。方法应用免疫组化EnVision两步法检测132例乳腺恶性肿瘤组织、29例乳腺良性肿瘤组织及35例乳腺癌旁组织中GATA3蛋白的表达,并将GATA3的表达与临床病理特征进行对比分析。结果(1)GATA3在正常人乳腺腺腔细胞中表达,乳腺癌组织中GATA3的阳性率为77%;(2)乳腺弥漫性大B细胞淋巴瘤和梭形细胞恶性肿瘤中GATA3不表达;(3) GATA3在三阴型乳腺癌中的阳性率低于其他分子类型乳腺癌(χ2=29．354,P<0．001)。结论 GATA3表达与乳腺肿瘤的病理类型和病理分级相关,可作为乳腺癌鉴别诊断和预后的标志物。     

RhoA、ROCK在乳腺癌组织中的表达及其意义

目的：研究RhoA、ROCK在乳腺癌组织中的表达,探讨其与乳腺癌转移的相关性。方法：应用免疫组化S-P法,检测30例正常乳腺、58例乳腺癌组织中RhoA、ROCK蛋白的表达情况。分析其表达结果与临床病理特征的关系。结果：①RhoA、ROCK蛋白在正常乳腺组织中的表达率分别为0%、0%,在乳腺癌组织中的表达率分别为70.7%、81.0%,两者在乳腺癌组织中的表达水平明显高于正常乳腺组织（P〈0.05）。②RhoA、ROCK蛋白表达与患者年龄、组织学分级无关（P〉0.05）,与肿瘤大小、临床分期及有无淋巴结转移有关。③RhoA、ROCK蛋白两者表达水平呈正相关关系（P〈0.05）。结论：RhoA、ROCK蛋白的表达与乳腺癌转移及预后有一定关系。结论：RhoA、ROCK的表达对评估乳腺癌的转移和预后具有一定的临床价值。     

SASH1和p-ERK在乳腺浸润性导管癌中的表达及意义

目的观察SASH1和p-ERK在乳腺浸润性导管癌组织和正常乳腺组织中的表达,探讨其与乳腺浸润性导管癌生物学行为和预后的关系。方法应用免疫组织化学方法检测100例乳腺浸润性导管癌及40例正常乳腺组织中SASH1和p-ERK的表达,并结合肿瘤临床病理特征进行分析。Western blot方法检测20例新鲜乳腺浸润性导管癌组织及10例新鲜正常乳腺组织中SASH1和p-ERK的表达水平;实时荧光定量PCR方法检测两组SASH1mRNA和p-ERK mRNA的表达水平。结果 SASH1蛋白在乳腺癌组织表达率(31%)低于在正常乳腺组织表达率(80%),表达与组织学分级、淋巴结转移有关,而与肿瘤大小、TNM分期、发病年龄、激素受体表达无明显相关性。p-ERK蛋白在乳腺癌组织表达率(62%)高于正常乳腺组织(20%),表达与肿瘤大小、组织学分级呈正相关,与发病年龄、TNM分期、组织学分级、有无淋巴结转移、激素受体表达无明显相关。乳腺癌中SASH1的表达与p-ERK表达呈负相关(P0.005)。Western blot与实时PCR结果显示,与正常乳腺组织相比,SASH1蛋白与mRNA在乳腺癌组织中表达水平显著降低,p-ERK蛋白与mRNA在乳腺癌组织中表达水平显著升高(P0.01)。结论 SASH1的低表达和p-ERK的高表达与乳腺浸润性导管癌的发生发展密切相关。     

BMP-2和VEGF在乳腺癌的表达及意义

目的探讨骨形成蛋白-2(BMP-2)和血管内皮生长因子(VEGF)在乳腺癌的表达及其与乳腺癌临床病理因素的关系。方法应用免疫组织化学S-P法检测68例乳腺浸润性导管癌组织BMP-2和VEGF的表达情况,应用WesternBlot方法检测30例乳腺癌、5例癌旁正常组织中BMP-2和VEGF的表达情况。结果BMP-2蛋白阳性信号位于乳腺癌细胞浆内,VEGF蛋白主要分布于乳腺癌与正常乳腺上皮细胞的胞浆内。有淋巴结转移的乳腺癌组织BMP-2和VEGF的表达明显高于无淋巴结转移者(<0.01);且BMP-2和VEGF表达与临床分期有关,与患者年龄、肿瘤大小无明显相关性。Western Blot结果显示BMP-2和VEGF在有淋巴结转移患者中表达高于无淋巴结转移者(<0.01)。结论BMP-2和VEGF在乳腺癌高表达与乳腺癌的淋巴结转移和临床分期有关。     

乳腺癌组织中Caveolin-1、MMP-2的表达及意义

目的 探讨Caveolin-1及MMP-2蛋白在乳腺癌及正常乳腺组织中的表达及两者的相关性.方法 采用EnVision法免疫组化检测86例乳腺癌及20例正常乳腺组织中Caveolin-1及MMP-2蛋白的表达.结果 乳腺癌中Caveolin-1的阳性率(52.3%)低于正常乳腺组织(95.0%)(P<0.05),而MMP-2的阳性率高于正常乳腺组织(P<0.05).Caveolin-1在乳腺癌的表达与淋巴结转移、临床分期相关(P<0.05),而与患者年龄、组织学分级及肿瘤大小无关(P>0.05).MMP-2在乳腺癌的表达与淋巴结转移、组织学分级及临床分期相关(P<0.05),而与患者年龄及肿瘤大小无关(P>0.05).在乳腺癌中Caveolin-1和MMP-2的表达呈负相关(r=-0.472,P<0.05).结论 Caveolin-1低表达与MMP-2过表达可能是乳腺组织恶性转变以及乳腺癌发生浸润转移的重要生物学标志,联合检测Caveolin-1和MMP-2对预测乳腺癌的浸润转移有重要意义.     

乳腺癌中Caveolin-1蛋白的表达及临床意义

目的 观察窖蛋白(Caveolin-1,Cav-1)在正常乳腺组织、良性增生性乳腺病及乳腺癌中的表达及其与乳腺癌临床病理特征的关系.方法 采用免疫组化SP法检测10例正常乳腺组织、15例良性增生性乳腺病和48例乳腺癌组织中Cav-1的表达,分析Cav-1在不同乳腺病变中表达的差异.结果 Cav-1在正常乳腺组织、良性增生性乳腺病及乳腺癌中的阳性率分别为40%、46%和100%,平均表达强度积分(±s)分别为0.90±0.83、0.93±1.16和6.24±2.18.其在正常乳腺组织与良性增生性乳腺病之间表达差异无统计学意义(P>0.05);在正常乳腺组织、良性增生性乳腺病与乳腺癌之间表达差异具有显著性(P<0.01);在乳腺癌不同组织学类型、病理分级、临床分期、细胞增殖指数(MIB-1/Ki-67)和有无淋巴结转移中阳性率和表达强度差异均无显著性(P>0.05).结论 Cav-1在正常乳腺组织及良性增生性乳腺病中呈低表达,在乳腺癌中呈高表达,表明Cav-1与乳腺癌的发生密切相关,但与乳腺癌的组织学类型、病理分级、临床分期、有无淋巴结转移和细胞增殖指数(MIB-1/Ki-67)无明显相关性.     

乳腺癌中RNF2的表达及其临床意义

目的 观察RNF2在乳腺病变组织及乳腺上皮细胞系中的表达,探讨其表达与乳腺癌临床病理特征的关系。方法 运用免疫组化En Vision两步法检测21例乳腺良性病变组织和112例乳腺癌组织中RNF2蛋白的表达,分析其表达与乳腺癌临床病理特征的关系。应用qRT-PCR法检测2株乳腺正常上皮细胞系和5株乳腺癌细胞系中RNF2基因的表达。结果 乳腺癌组织中RNF2蛋白表达水平与乳腺良性病变组织相比显著升高(P0.05),且其表达与乳腺癌肿瘤直径、腋窝淋巴结转移数目、TNM分期显著相关(P均0.05);与患者年龄、组织学分级、ER、PR、HER-2表达情况无显著相关(P均0.05);乳腺癌细胞系RNF2 mRNA水平亦高于乳腺良性上皮细胞系(P0.05)。结论 RNF2在乳腺癌组织中高表达,可作为乳腺癌治疗的潜在靶点。     

膜联蛋白A2在乳腺癌及乳腺纤维腺瘤中的表达及意义

目的 研究膜联蛋白A2 (Annexin Ⅱ,ANX A2)在乳腺浸润性导管癌和乳腺纤维腺瘤中表达,以探讨其在乳腺癌发生发展中的作用.方法 分别使用免疫组织化学染色(SP)法和逆转录聚合酶链反应(RT-PCR)法检测乳腺浸润性导管癌和乳腺纤维腺瘤中ANX A2的蛋白表达水平和mRNA表达水平,并分析其在不同病理分级、临床分期及有无淋巴结转移的乳腺浸润性导管癌组织中的表达情况.结果 免疫组化结果显示乳腺浸润性导管癌组织中ANX A2表达高于乳腺纤维腺瘤(P＜0.05),RT-PCR结果也显示乳腺浸润性导管癌中ANX A2 mRNA的表达高于乳腺纤维腺瘤(P＜0.05).乳腺癌中ANX A2的表达与年龄、病理分级、临床分期和淋巴结转移呈正相关.结论 乳腺浸润性导管癌中annexinA2表达明显高于乳腺纤维腺瘤,annexinA2可能是乳腺癌的生物学标记物之一,其在乳腺癌的发生发展中可能扮演重要的角色.     

受体酪氨酸激酶EphA7在乳腺癌中的表达及其临床意义

目的观察受体酪氨酸激酶EphA7在乳腺癌和正常乳腺组织中的表达,探讨EphA7蛋白表达的临床意义。方法应用免疫组化En Vision法染色检测乳腺正常细胞系、乳腺癌肿瘤细胞系和150例浸润性导管癌组织中EphA7的表达,分析其表达与临床病理特征的相关性。结果 EphA7蛋白在乳腺癌细胞系和浸润性导管癌中表达丢失,其表达水平与患者年龄(r_s=-0.157,P=0.055)、肿瘤分级(r_s=-0.331,P0.001)呈负相关;与淋巴结转移(r_s=0.245,P=0.002)、TNM分期(r_s=0.217,P=0.008)、HER-2表达(r_s=0.179,P=0.028)呈正相关。结论 EphA7在多数乳腺癌细胞中表达丢失,可能在乳腺癌发生和转移中发挥重要作用。     

肿瘤标志物SURVIVIN及P27蛋白在肾细胞癌中表达的临床意义

目的：探讨新的凋亡相关基因Survivin蛋白和p27蛋白肿瘤标志物在人肾细胞癌中的表达及临床意义。方法：采用免疫组化SP法分别测定50例肾癌和12例正常肾组织中Survivin蛋白及p27蛋白的表达,并分析其与肾癌临床、病理的关系。结果：Survivin蛋白在肾癌组织中表达阳性率为68%（34/50）,而正常组织中未见表达,两者有统计学意义（P〈0.01）。肾癌中Survivin蛋白的表达与肾癌的病理分级呈正相关（P〈0.05）。而p27蛋白在正常肾组织中的阳性率为83.3%（10/12）,在肾癌组织中的阳性率为42%（21/50）,两者有统计学意义（P〈0.01）。p27蛋白表达与肾癌的分级呈负相关（P〈0.01）。结论：Survivin蛋白表达水平与肾癌的临床分期、淋巴结转移密切相关,且与p27蛋白呈负相关。联检Survivin蛋白和p27蛋白有助于提高对肾癌预后的评估,并可作为判定肾癌生物学行为的客观指标。     

宫颈癌组织中survivin和CD44v6的表达及其与HPV16/18感染的相关性

目的研究survivin、CD44v6在宫颈癌组织中的表达及其与HPV16/18感染的相关性,以探讨宫颈癌的发生机制。方法用免疫组化方法进行survivin和CD44v6的检测,用PCR检测HPV16/18感染情况。结果survivin和CD44v6的阳性率在宫颈癌组织中远高于CIN和正常宫颈组织,差异显著(均P<0.01),其表达率与淋巴结转移有关(均P<0.05)。CD44v6随着临床分期、病例分级的升高阳性率升高(P<0.05),survivin的阳性率则随着病例分级的升高而增加(P<0.05)。HPV16/18在正常宫颈组织、CIN和宫颈癌中的阳性率逐渐升高(P<0.01),但与临床分期、病理分级、淋巴转移无关。survivin与HPV16/18感染有相关性(P<0.05)。结论宫颈癌组织中survivin的异常表达与HPV16/18感染有关。survivin和CD44v6与宫颈癌的恶变程度有关,可作为宫颈癌筛查预后判断的有利指标。     

Expression of Bcl-2 and Survivin in uterine cervical carcinogenesis and correlation between the expression and infection of HPV_(16/18)

Carcinomaofthecervixisthesecondleading causeofdeathamongwomenworldwide.Each year,anestimated500000casesarenewlydiag nosed[1].Manystudiesshowedinfectionofhu manpapillomavirus(HPV)wasoneofthemost importantetiologicfactorsforcervicalcarcinoma[24].Morethan95%ofallcervicalcarcinomas havebeenfoundtobeassociatedwithHPV(ma inlytypes16and18)[5].Thestudiesinmolec ularoncologyrecentlyshowedthatitresultedin occurrenceanddevelopmentofcervicalcarcinomasthatcarcinogenicfactorsmadeproto oncogene activatean…     

Survivin expression in ovarian carcinoma: correlation with apoptotic markers and prognosis.

Survivin is a novel inhibitor of apoptosis commonly detected in tissues during fetal development and in cancer, but not usually in normal tissues. Expression of this protein may be of prognostic significance and therapeutically relevant in many cancers. We assessed survivin expression in ovarian carcinoma, correlating results with expression of other anti-apoptotic (bcl-2, bcl-x, mutant p53) and pro-apoptotic (bax) markers, with prognostic parameters, and prognosis. Paraffin-embedded sections of 49 ovarian carcinoma were immunostained for survivin, bcl-2, bcl-x, bax, and p53. Expression was evaluated in nuclei and cytoplasm, as intensity (0-3+), and percentage of positive cells was scored on a four-tiered system with <10% as negative. Frequency of survivin, bcl-2, bcl-x, bax, and p53 was 73.5%, 36.7%, 93.9%, 77.6%, and 60.4%, respectively. There was significant correlation between nuclear survivin expression and grade (P =.0014), histologic type (P =.0376), and mutant p53 (P =.0414). Survivin expression did not correlate with bcl-2, bcl-x, or bax expression, stage, or overall or disease-free survival. The majority (74%) of ovarian carcinoma show survivin expression, which correlates with poor prognostic parameters (high grade, histologic type, p53 mutation) but not with survival. Therapeutic targeting of survivin in ovarian carcinoma is a future possibility.     

Survivin expression in non-small-cell lung carcinomas: correlation with apoptosis and other apoptosis-related proteins, clinicopathologic prognostic factors and prognosis.

The role of survivin that regulates the biological behavior of non-small-cell lung carcinoma (NSCLC) is still controversial. We aimed to investigate survivin expression in NSCLC and to define any correlation with expressions of p53, bcl-2, bax, apoptotic index (AI), tumor cell proliferation, clinicopathologic variables, and overall survival. Tumors of 63 patients with NSCLC were examined for expressions of survivin, p53, bcl-2, bax, and Ki-67 by immunohistochemistry. AI was also evaluated. Results for each antibody were correlated with each other, and with clinicopathologic variables including age, sex, histologic subtype, TNM (T: primary tumor, N: regional lymph node metastasis, M: distant metastasis) stage, lymph node status, smoking history, and prognosis. Nuclear survivin expression was inversely correlated with p53 expression (P = 0.04, r = - 0.367), and tumor stage (P = 0.03, r = - 0.273), and positively correlated with tumor cell proliferation (P = 0.009, r = 0.329). Cytoplasmic survivin expression positively correlated with smoking history (P = 0.02, r = 0.282). Survivin/bax ratio was inversely correlated with AI (r: - 0.004). By Kaplan-Meier analysis, TNM stage (P < or = 0.001), lymph node metastasis (P = 0.04), and Ki-67 index (P < or = 0.001) were associated with survival, whereas survivin was not. In multivariate analysis, only TNM stage was an independent predictor. Although survivin and other apoptosis-related protein expressions fail to predict the clinical outcome, the present findings suggest that survivin is involved in tumor cell apoptosis and proliferation and may play a role in critical steps of cancer progression in NSCLC.     

宫颈癌组织中Bcl-2、Survivin、CD44v6的表达及其与HPV16/18感染的相关性

目的 研究Bcl-2、Survivin和CD44v6在宫颈癌组织中的表达及其与细胞凋亡、HPV16／18感染的相关性，以探讨宫颈癌的发生机制，指导其诊断预后。方法 采用免疫组化对宫颈组织石蜡标本进行Bcl-2、Survivin、CD44v6的检测，同时采用TUNEL和PCR技术检测细胞凋亡指数（AI）和HPVl6／18感染情况。结果 Bcl-2、Survivin、CD44v6的阳性率和AI在宫颈癌组织中与CIN、正常宫颈组织有差异，且随着临床分期、病理分级的升高阳性率有差异，其表达率与淋巴结转移有关。HPV16／18在正常宫颈组织、CIN和宫颈癌中的阳性率逐渐升高，差异有统计学意义。Bcl-2、Survivin和AI均与HPV16／18感染有相关性。结论 宫颈癌组织中Bcl-2、Survivin、CD44v6的异常表达和HPV16／18感染有关，与宫颈癌的恶变程度有关，可作为宫颈癌筛查预后判断的有利指标。     

Major histocompatibility complex status in breast carcinogenesis and relationship to apoptosis

Major histocompatibility complex (MHC) molecules are of central importance in regulating the immune response against tumors. In this study we used immunohistochemistry to study human leukocyte antigen (HLA) class I and II antigen expression in normal breast tissues and benign, preneoplastic, primary, and metastatic breast lesions using antibodies against beta-2-microglobulin (beta2-m), heavy-chain, and HLA-DR antigens. Whereas all normal tissues and benign lesions were positive for beta2-m and HLA-A, -B, and -C antigens, total loss of HLA class I antigens was found in 37% (11 of 30) of in situ carcinomas, in 43% (56 of 131) of the primary tumors, and in 70% (31 of 45) of the lymph node metastases. HLA-DR was also underexpressed in breast cancer cells; thus 20% (6 of 30) of in situ carcinomas, 15% of invasive carcinomas (20 of 131), and only 1 metastatic case were positive for this antigen. Both HLA class I and II antigen expression were more frequently down-regulated in metastatic lesions than in primary breast lesions (P <0.05), and a tendency toward a simultaneous defective expression of HLA class I and II antigens was observed in primary carcinomas (P = 0.07). However, no correlation was found between the expression of any of the aforementioned molecules and pathological parameters or survival. Interestingly, HLA class I expression was expressed more frequently in tissues with high apoptotic activity and was significantly associated with the expression of the proapoptotic bax gene (P = 0.02), and was inversely associated with expression of the antiapoptotic bcl-2 gene (P = 0.03). We conclude that alterations in HLA class I and II antigen expression are early events in breast carcinogenesis and play significant roles in metastatic progression. In addition, their expression is correlated with apoptosis-regulating proteins, which may influence the cytotoxicity of T cells against HLA class I-specific tumor antigens.     

Survivin, a member of the inhibitors of apoptosis family, is down-regulated in breast carcinoma effusions

We analyzed the expression and prognostic role of inhibitors of apoptosis in breast carcinoma effusions. We used immunoblotting to analyze 22 effusions for XIAP, survivin, and livin expression. Based on immunoblotting results, 49 effusions and 46 corresponding solid tumors were immunostained for XIAP and survivin. Results were analyzed for association with anatomic site, clinicopathologic parameters, and survival. Immunoblotting showed frequent expression of XIAP and survivin and no expression of livin. Carcinoma cells in effusions showed lower survivin immunostaining compared with lymph node metastases (P = .008) and primary carcinomas (P = .041). Higher cytoplasmic survivin expression correlated with poor disease-free survival for patients with postchemotherapy effusions (P = .035). XIAP and survivin, but not livin, are frequently expressed in advanced breast carcinoma. Survivin is down-regulated in effusions compared with solid tumors, possibly in relation to the different cellular economy at this anatomic site. Survivin expression may predict disease-free survival for patients with postchemotherapy effusions.     

宫颈癌组织中MCM4、TFF2的表达及其与HPV_(16/18)感染的相关性研究

研究MCM4、TFF2在宫颈癌组织中的表达及其与HPV16/18感染的相关性,以探讨宫颈癌的发生机制,进一步寻找有利于宫颈癌诊断的新的分子标志物,以指导其诊断与预后。采用免疫组织化学方法对50例宫颈癌石蜡标本、宫颈上皮内瘤变CINⅠ20例、CINⅡ-Ⅲ20例、正常宫颈组织20例进行MCM4、TFF2的检测,同时采用PCR技术检测HPV16/18感染情况。结果:(1)在宫颈癌组织中MCM4的阳性率高于CIN和正常宫颈组织,差异有统计学意义(P<0.05),且MCM4阳性表达率与病理分级、淋巴结转移有关,差异有统计学意义(均P<0.05)。在宫颈癌组织中MCM4的阳性表达率与年龄分组、临床分期无关(均P>0.05)。在宫颈癌组织中TFF2的阳性率低于CIN和正常宫颈组织,差异有统计学意义(P<0.05),且TFF2阳性表达率与年龄分组有关,差异有统计学意义(P<0.05),其阳性表达率均与临床分期、病理分级、淋巴转移无关(均P>0.05);(2)HPV16/18在正常宫颈组织、CIN和宫颈癌中的阳性率逐渐升高,差异有统计学意义(P<0.05),但与年龄、临床分期、病理分级、淋巴转移无关(均P>0.05);(3)在宫颈癌组织中,MCM4与HPV16/18感染呈正相关(rs=0.634,P<0.01),TFF2与MCM4、HPV16/18感染呈负相关(rs=-0.375,P<0.01;rs=-0.500,P<0.01)。宫颈上皮内瘤变及宫颈癌组织中MCM4、TFF2表达的改变可能与HPV16/18感染有关,且互相作用,共同影响CIN的发展及宫颈癌的发生。这些指标综合分析可能为阐明HPV16/18的恶性转化机制以及为提高宫颈癌及其癌前病变诊断率提供参考依据。MCM4的异常表达与宫颈癌的恶变程度有关,可作为宫颈癌筛查、预后判断的有利指标。     

Prognostic significance of anti-apoptosis proteins survivin and bcl-2 in non-small cell lung carcinomas: a clinicopathologic study of 102 cases.

Inhibitors of apoptosis, including bcl-2 and survivin (a novel gene encoding a unique apoptosis inhibitor), regulate cell proliferation by promoting cell survival. Although survivin has been detected in several human cancers, its prognostic significance and relationship to bcl-2 are not well characterized in lung cancer. Tissue sections from 102 non-small cell lung carcinomas (NSCLC) were immunostained using antibodies against survivin and bcl-2. Staining results were correlated with prognostic variables. Immunoreactivity for survivin and bcl-2 was observed in 53% and 21% of NSCLCs, respectively. Fifty-two percent of the 50 squamous cell carcinomas and 54% of the 52 adenocarcinomas expressed survivin. Survivin positivity correlated with tumor stage in squamous cell carcinoma. On univariate analysis, survivin expression correlated with decreased patient survival in NSCLC and in the subset of squamous cell carcinomas, but not in adenocarcinomas. On multivariate analysis, survivin was an independent predictor, along with distant metastasis and large tumor size. Eighteen percent of squamous cell carcinomas and 24% of adenocarcinomas expressed bcl-2. On univariate analysis, bcl-2 expression correlated with increased patient survival in NSCLC and in the subset of squamous cell carcinomas. An inverse correlation between the expression of survivin and bcl-2 was noted. Survivin immunoreactivity is an independent predictor of shortened survival in NSCLC, while bcl-2 protein expression correlated with prolonged patient survival. These findings indicate an inverse relationship between survivin and bcl-2 expression and suggest that these two inhibitors of apoptosis function through different pathways in the regulation of tumorigenesis in NSCLC.     

IL-6, its receptors and its relationship with bcl-2 and bax proteins in infiltrating and in situ human breast carcinoma

AIMS: To characterize the expression pattern of IL-6 and its receptors (IL-6R(alpha) and gp130), to relate this pattern to bcl-2 and bax expression and to elucidate the effects on the proliferation/apoptosis equilibrium in benign conditions and in situ and infiltrating breast cancer. METHODS AND RESULTS: The immunoexpression of IL-6 and its receptors (IL-6R(alpha) and gp130), and their relationship with bcl-2 and bax proteins, were studied in in situ and infiltrating tumours and in benign breast lesions by means of Western blotting and immunohistochemistry. The percentages of samples positive for IL-6, bcl-2 and bax and their immunoreaction densities were higher in in situ carcinomas and infiltrating tumours than in benign lesions; although in in situ lesions were not so high as in infiltrating tumours, except for bax, whose immunoexpression was as weak as in benign conditions, resulting in a bcl-2/bax ratio higher than in infiltrating tumours. CONCLUSIONS: The high expression of IL-6 and its receptors in tumours might be related to the enhanced cell proliferation occurring in breast cancer. IL-6 could act by increasing bcl-2 expression and thus altering the proliferation/apoptosis balance toward neoplastic cell proliferation. The increased bax immunoreactivity observed only in infiltrating tumours, which was not so high as the increase in bcl-2 immunoreactivity, might be interpreted as an attempt to hinder cell proliferation.