功能性单克隆抗体40E11靶向治疗肺癌的实验研究

目的:检测分析抗肺癌单克隆抗体40E11识别的靶抗原在肺癌细胞系及肺癌组织中的表达,研究单克隆抗体40E11体内外抑瘤功能,并初步鉴定其识别的抗原蛋白,为肺癌的靶向治疗提供候选抗体药物及靶标.方法:应用细胞免疫荧光检测单克隆抗体40E11所识别的靶抗原在肺癌细胞系中的表达及定位,免疫组化检测其在人肺癌组织中的表达;CCK-8法检测分析40E11对肺癌细胞增殖的影响.裸鼠体内治疗实验研究40E11对移植瘤生长的抑制作用.Western bloting鉴定该单克隆抗体识别的抗原的分子量.结果:单克隆抗体40E11识别的抗原在人肺腺癌细胞(A549、GLC-82、ANIP-973)、人肺鳞癌细胞(GLC-P)的胞内及胞膜均有表达;该抗原在84.6％的人肺癌组织中的表达较癌旁组织显著上调;CCK-8法检测结果显示单克隆抗体40E11明显抑制肺癌细胞体外生长;抗体治疗实验结果表明单克隆抗体40E11明显抑制体内肺癌细胞生长,其抑制率达64.4％,P＜0.05;蛋白质印迹法显示40E11识别的抗原相对分子质量约为100×103.结论:抗肺癌单克隆抗体40E11在体内外能显著抑制肺癌细胞的生长,为肺癌的靶向治疗提供具有重要应用价值的候选抗体药物.     

单克隆抗体12H6的靶抗原在肺癌细胞中的表达及功能研究

[目的]分析抗肺癌单抗12H6的靶抗原在肺癌细胞系和肺癌组织中的表达,研究单抗12H6体内外生物学功能.[方法]细胞免疫荧光、流式细胞荧光法检测单抗12H6靶抗原在3种肺癌细胞系中的表达及其定位,免疫组化法检测其在人肺癌组织中表达及特异性;Transwell法和CCK-8法分别检测12H6体外对肺癌细胞系侵袭和增殖功能的影响.共接种模型裸鼠体内治疗实验研究12H6对移植瘤生长的抑制作用.[结果]单抗12H6的靶抗原在人肺腺癌细胞(A549、GLC-82)、人肺鳞癌细胞(GLC-P)的胞内及胞膜均有表达,在3种细胞系胞膜的表达比例分别为31.2％、15.4％和16.7％.单抗12H6在人肺癌组织中的表达比例为80.6％,较配对癌旁组织显著上调.单抗12H6在体外能明显抑制肺癌细胞侵袭和增殖;体内能明显抑制移植瘤生长,抑制率为40％.[结论]单抗12H6具有优良的体内外抑瘤功能,可能为肺癌靶向治疗提供潜在的靶向治疗药物.     

肺癌抑制性抗体及其抗原的鉴定

目的：鉴定抑制肺癌细胞生长的功能性单克隆抗体1E2及其抗原，为治疗肺癌提供有潜力的靶向抗体治疗剂和分子靶位。方法：采用活细胞荧光、MTT细胞增殖实验、ELISA、动物体内治疗实验等方法检测鼠单克隆抗体1E2对人肺癌细胞增殖的抑制、单抗与癌细胞的结合部位、单抗的亚类和单抗对肺癌移植瘤的抑制，以Western blotting和MALDITOF质谱方法鉴定该功能性单抗的抗原。结果：单抗1E2能够与肺癌细胞GLC82和NCI-H520的细胞膜结合，在体外能够明显抑制肺癌细胞的增殖。动物实验表明单抗1E2能够抑制肺癌移植瘤的生长，抑制率达49％。Western blotting显示其抗原相对分子质量约110000，质谱鉴定该抗原为氨甲酰磷酸合成酶（carbamoyl-phosphate synthetase1，CPS1）。结论：单抗1E2能够在体内外抑制肺癌的生长，具有成为肺癌靶向治疗剂的潜力。该抗体识别的抗原CPS1可表达于肺癌细胞的细胞膜，可能是一个肺癌靶向治疗的新靶位。     

功能差异细胞模型筛选抗肺癌功能性单克隆抗体及其抗原

目的:筛选获取抗肺癌细胞膜的功能性单克隆抗体及其靶抗原，为肺癌靶向治疗提供候选治疗剂及靶标。方法: 将新鲜人肺癌组织细胞免疫BALB/c小鼠,采用脾细胞融合法制备大容量单克隆抗体库。建立肺癌细胞增殖、侵袭、迁移等定向功能差异细胞模型，采用活细胞免疫荧光与功能差异模型筛选其抗原在定向功能（细胞增殖、迁移、侵袭）差异模型细胞膜上差异表达的单抗，再经体外相应功能实验筛选具有抑制作用的功能性单抗，Western blotting鉴定这些单抗的抗原，裸鼠体内抑瘤实验鉴定部分单抗对肺癌的抑制作用。结果: 细胞融合后共获得2 893株杂交瘤克隆，其中与肺癌细胞膜结合反应的309株。分别建立了3种体外肺癌细胞增殖、侵袭、迁移差异模型用于筛选，筛选获得20株单抗能显著抑制肺癌细胞增殖、10株单抗能显著抑制肺癌细胞侵袭、5株单抗能显著抑制肺癌细胞迁移（P<0.05或P<0.01）。Western blotting鉴定了其中6株的抗原。选取其中2株单抗均能在裸鼠体内显著抑制肺癌移植瘤的生长（P<0.05或P<0.01）。结论: 采用大容量功能性单抗库技术结合功能差异细胞模型可批量筛选获得具有体内外抑制肺癌细胞恶性生物学行为的功能性单抗，为筛选肺癌靶向治疗剂及靶标提供了一种潜在的新方法。     

高表达HMGB1肺癌细胞系的筛选及意义

背景与目的 在人肺鳞癌细胞株YTMLC-9、人肺腺癌细胞株A549、人大细胞肺癌细胞株L9981及人小细胞癌细胞株NCI-H446中筛选高表达HMGB1的细胞株,作为人肺癌细胞HMGB1基因研究的理想材料.方法 采用实时荧光定量PCR和Western blot方法对人肺癌细胞HMGB1基因在4株细胞中的mRNA和蛋白水平的表达进行检测,筛选出高表达HMGB1基因的人肺癌细胞株.结果 人肺鳞癌细胞株YTMLC-9、人肺腺癌细胞株A549、人大细胞肺癌细胞株L9981及人小细胞癌细胞株NCI-H446中均有HMGB1基因表达,其中人大细胞肺癌细胞株L9981表达水平最高,mRNA是表达量最低的人肺腺癌细胞株A549mRNA表达量的10.3倍;人大细胞肺癌细胞株L9981 HMGB1蛋白表达水平最高,与其它3种人肺癌细胞株相比有统计学差异(P<0.001).结论 人大细胞肺癌L9981细胞株为HMGB1高表达细胞株,可作为进行肺癌细胞中研究HMGB1的实验材料.     

miR-200a抑制YAP1基因表达对肺癌细胞增殖的影响

  目的   研究微小RNA-200a（miR-200a）对肺癌细胞增殖的影响,并探讨其分子机制。   方法   采用Real-time PCR检测15例非小细胞肺癌组织和对应癌旁组织、人肺癌细胞株（A549、NCI-H520、SK-MES-1）及人正常肺支气管上皮细胞株16HBE中miR-200a的表达水平。用CCK-8法检测miR-200a对A549肺癌细胞增殖活性的影响。通过生物信息学方法预测miR-200a可能的靶基因,双荧光素酶报告基因实验结合Real-time PCR和Western blot验证miR-200a对靶基因YAP1的调控作用。CCK-8法检测下调靶基因YAP1对A549肺癌细胞株增殖活性的影响。   结果   miR-200a在非小细胞肺癌组织和肺癌细胞系中表达明显降低（P < 0.01）。上调miR-200a表达后明显抑制A549肺癌细胞的增殖活力（P < 0.01）。双荧光素酶报告基因显示miR-200a可以直接作用于靶基因YAP1的3'-UTR区域抑制荧光素酶活性（P < 0.01）,Real-time PCR和Western blot检测显示上调miR-200a的表达能够明显下调A549肺癌细胞YAP1 mRNA和蛋白的表达水平（P < 0.01）。CCK-8法显示下调YAP1的表达能够明显抑制A549肺癌细胞的增殖活性（P < 0.01）。   结论   miR-200a通过靶向作用于YAP1基因来抑制肺癌细胞的增殖,从而在肺癌中发挥抑癌基因的功能。      

腺病毒介导的FasL基因转移及对肺癌细胞生长和凋亡的影响

目的：探讨FasL基因对人肺癌的作用以及FasL基因治疗肺癌的可能性。方法：通过腺病毒载体介导FasL基因转移到低水平表达FasL的人肺腺癌细胞系A549,对FasL基因的表达、细胞生长的抑制和肿瘤生长模型的治疗效果进行分析。结果：外源性FasL基因在靶细胞高水平的表达显著抑制了A549的生长和集落形成，流式细胞仪检测显示细胞G1期阻滞并发生了凋亡。瘤内注射Ad-FasL对裸鼠体内移植瘤有一定的抑瘤作用。结论：FasL基因参与了肿瘤细胞凋亡的诱导，能抑制肺腺癌细胞的生长，因此本基础在肿瘤的基础治疗上有着广泛的应用前景。     

人肺癌细胞株中hnRNP A2/B1表达的研究

目的 研究人肺癌细胞株中核内不均一核糖核蛋白(hnRNP)A2/B1及hnRNP B1的表达。方法 采用特异性hnRNP A2／B2及hnRNP B1引物,应用RT-PCR方法研究肺癌细胞株hnRNP A2／B1 mRNA的表达,以抗hnRNP B1单克隆抗体免疫细胞化学染色方法研究肺癌细胞hnRNP A2/B1蛋白的亚细胞定位。结果 RT—PCR显示人肺腺癌细胞株SPC-A1及Y-90,小细胞肺癌细胞株NCI-H446及鳞癌细胞株A431均表达hnRNP A2／B1及hnRNP B1,其PCR产物分子量分别在661及1039bp左右,与预期大小的hnRNP A2/B1 cDNA片断相符。免疫细胞化学研究发现,肺腺癌细胞株SPC—A1及Y-90．小细胞肺癌细胞株NCI—H446及鳞癌A431的细胞浆及细胞核内均可见特异的hnRNP B1染色,鳞癌A43l及小细胞肺癌NCI—H446 hnRNP B1染色较肺腺癌细胞株SPC—A1及Y-90明显。结论 肺癌细胞株hnRNP A2／B1及hnRNP B1表达明显增高。     

Hsa-let-7诱导肺癌细胞凋亡与G0/G1期阻滞及其分子机制

目的：研究hsa-let-7对肺癌细胞功能的影响并探索其机制.方法：构建重组质粒pGenesilTM-let-7a和pGenesilTM-control,经脂质体介导稳定转染人肺鳞癌细胞系KUM-LK2、肺腺癌细胞系A549,小细胞肺癌细胞系H446,经qRT-PCR检测转染后3种肺癌细胞中let-7a的表达差异,Western blot检测let-7a下游基因Ras、ERK的表达差异,流式细胞仪检测细胞凋亡率及细胞周期,探索let-7a通过MAPK信号转导通路影响肺癌细胞的功能及机制.结果：转染pGenesilTM-let-7a后,let-7a在实验组肺癌细胞中的表达显著高于对照组肺癌细胞,Western blot证实p-Ras、p-ERK在实验组细胞中的表达显著低于对照组（P＜0.05）,而t-Ras及t-ERK的表达差异不显著（P＞0.05）;同时实验组肺癌细胞的凋亡率显著高于对照组肺癌细胞,实验组肺癌细胞S期比例显著低于对照组,而G0/G1期比例显著高于对照组（P＜0.05）.结论：Let-7a通过作用于靶基因Ras,影响ERK的表达,调节MAPK信号转导通路,促进肺癌细胞的凋亡,使G0/G1期肺癌细胞比例增加,可能在肺癌的发生发展中起重要的作用.     

放射诱导抑瘤素M靶向肿瘤表达治疗肺癌实验研究

目的利用放射敏感性调控序列诱导抑瘤素M(OSM)靶向肺癌表达，探索肺癌治疗新方法。方法利用基因重组构建放射可调控的OSM表达载体pEO，转染肺腺癌A549细胞，观察γ线照射后细胞OSM表达及其对细胞相对存活分数和存活曲线的影响。利用肺癌移植瘤观察不同处理的抑瘤效应。结果γ线可诱导OSM在pEO转染肺癌细胞表达显著上调，呈剂量依赖性。pEO转染肺癌细胞株对辐射敏感性增强，增殖活性显著受抑。6Gy照射联合pEO转染可显著抑制移植瘤生长，并可使30％的移植瘤完全消退。结论由辐射敏感性启动子驱动的OSM肿瘤靶向性表达，可望为肺癌治疗提供一条新途径。     

Targeted Efficacy of Dihydroartemisinin for Translationally Controlled Protein Expression in a Lung Cancer Model

Objective: Lung cancer is one of the malignant tumors with greatest morbidity and mortality around theworld. The keys to targeted therapy are discovery of lung cancer biomarkers to facilitate improvement of survivaland quality of life for the patients with lung cancer. Translationally controlled tumor protein (TCTP) is one ofthe most overexpressed proteins in human lung cancer cells by comparison to the normal cells, suggesting thatit might be a good biomarker for lung cancer. Materials and Methods: In the present study, the targeted efficacyof dihydroartemisinin (DHA) on TCTP expression in the A549 lung cancer cell model was explored. Resultsand Conclusions: DHA could inhibit A549 lung cancer cell proliferation, and simultaneously up-regulate theexpression of TCTP mRNA, but down-regulate its protein expression in A549 cells. In addition, it promotedTCTP protein secretion. Therefore, TCTP might be used as a potential biomarker and therapeutic target fornon-small cell lung cancers.     

吉非替尼对肺癌细胞生长的抑制作用

目的探讨靶向治疗药物吉非替尼(ZD1839)对肺癌细胞生长的抑制作用。方法应用细胞培养和MTT等方法研究了ZD1839对13株人肺癌细胞生长的抑制作用。结果在13株肺癌细胞中,有一株肺癌细胞PC-9对ZD1839高度敏感,一株肺癌细胞A549中度敏感,有效率15.38%。其余11株肺癌细胞对ZD1839不敏感。结论吉非替尼是一种新型有效的肺癌分子靶向治疗药物。     

Human interferon-gamma enhances expression of ganglioside GM2 on human lung cancer cells and their susceptibility for antiganglioside GM2 monoclonal antibody-dependent cellular cytotoxicity

Interferons are known to modulate several cellular functions by the induction of various proteins. In this study, we demonstrated that human interferon-gamma (HuIFN-gamma) enhanced the expression of ganglioside GM2 (GM2), which is a kind of tumor-associated antigen substantially expressed in human lung cancer and that human lung cancer cells expressing GM2 became more susceptible to anti-GM2 monoclonal antibody (mAb)-dependent tumor cell killing mediated by human effector cells after HuIFN-gamma treatment. GM2 expression on human lung cancer cells treated with or without HuIFN-gamma was measured by flow cytometry. The antibody-dependent cellular cytotoxicity (ADCC) activity was assessed by 4-h 51Cr release assay. HuIFN-gamma enhanced GM2 expression on human small-cell lung cancer (SCLC), SBC-3, and human non-small-cell lung cancer (NSCLC), A549 cells in a dose-dependent manner. The optimal concentration of HulIFN-gamma was 1,000 U/ml. The effect of HulFN-gamma reached maximum after 4 days of culture. HulFN-gamma did not have any effect to enhance the expression of other gangliosides in SBC-3 cells. No other cytokines used in this study modulated GM2 expression in SBC-3 cells. Anti-GM2 mAb-dependent ADCC activities induced by lymphocytes and monocytes were more potent against IFN-gamma-treated SBC-3 and A549 cells than nontreated cells. Taken together, HulFN-gamma combined with anti-GM2 mAb may be useful for immunotherapy against GM2-positive human lung cancer.     

一株靶向CD90+MHCC97-L细胞单克隆抗体治疗肝癌的实验研究

目的:研究抗人肝癌干细胞单抗28C10体内外功能,为肝癌干细胞的靶向治疗提供有应用价值的候选治疗剂。方法:采用无血清成球实验、侵袭实验和CCK-8方法等检测分析28C10单抗对MHCC97-L sphere的细胞自我更新、侵袭和耐药的影响。裸鼠体内治疗实验研究单抗28C10联合顺铂对MHCC97-L移植瘤生长的作用。Western-Blot方法鉴定该单抗识别抗原的分子量。结果:流式细胞检测结果显示单抗28C10能够识别MHCC97-L中CD90阳性细胞的比例为2.75%。体外功能实验结果显示单抗28C10能显著抑制MHCC97-L sphere细胞的无血清成球能力和侵袭能力,抑制率分别达33.33%和53.8%。28C10能显著抑制MHCC97-L sphere的顺铂耐药能力,其IC50为0.74 μg/ml,而对照组的IC50为1.42 μg/ml。抗体体内治疗实验结果显示,低、高剂量抗体28C10均能抑制肝癌移植瘤的生长,抑制率分别达到了24.0%和67.7%,单独顺铂组肝癌移植瘤的抑制率为35.9%,而顺铂联合高剂量抗体28C10组对肝癌移植瘤的抑制率达到70.1%。Western-Blot结果显示单抗28C10识别的抗原蛋白分子量约100 kD。结论:筛选获得了1株抗肝癌干细胞的功能性单抗,为靶向肝癌干细胞治疗肝癌奠定了重要的基础。     

Detection of locally recurrent colorectal cancer with radiolabeled monoclonal antibody H-15.

H-15 (HT-29-15) is an IgG1 mouse monoclonal antibody (mAb) to a cell surface antigen (molecular mass, 200,000 daltons) present on virtually all colorectal cancers and also in normal pancreatic ducts and bile ducts, but not in other normal tissues. The biological distribution and imaging characteristics of iodine-131 (131I)-labeled mAb H-15 were studied in 5 primary colorectal cancer patients and 9 patients with local recurrence of colorectal cancer. H-15 mAb labeled with 0.5-10 mCi of 131I was administered 7 to 8 days before surgery at 4 dose levels, ranging from 0.2 to 6 mg. Selective mAb H-15 localization to tumor tissues was demonstrated in 6 of 12 patients with antigen-positive tumors: in two patients, recurrent tumors were negative to H-15 mAb, although the primary tumors were positive. In six patients with positive radioimaging, tumor:normal tissue ratios ranged from 2.05 to 5.35 and tumor:serum ratios from 1.18 to 2.73. The clarity of images seems to correlate well with the latter ratios. Technetium-99 (99mTc)-albumin blood pool studies in selected cases showed that local recurrence of colorectal cancers was hypovascular, emphasizing the selective localization of mAb H-15 despite poor blood flow distribution in the tumors. The results altogether demonstrated that radioimmunodetection with 131I mAb H-15 is valuable for differentiating recurrent colorectal cancer from granuloma formation after surgery.     

In vitro and in vivo targeting properties of iodine-123- or iodine-131-labeled monoclonal antibody 14C5 in a non-small cell lung cancer and colon carcinoma model.

PURPOSE: The monoclonal antibody (mAb) 14C5 is a murine IgG1 directed against a yet undefined molecule involved in cell substrate adhesion found on the surface of malignant breast cancer tissue. mAb 14C5 is able to inhibit cell substrate adhesion and invasion of breast cancer cells in vitro. In normal tissues as well as in the stroma surrounding in situ carcinomas of the breast, no expression of the antigen 14C5 occurs. The aim of this study was to investigate the in vitro and in vivo targeting properties of 123I- and 131I-labeled mAb 14C5 as a novel agent for radioimmunodetection and radioimmunotherapy. EXPERIMENTAL DESIGN: Internalization of mAb 14C5 was investigated with 125I-labeled mAb 14C5 and by confocal laser scanning microscopy. Biodistribution studies of 131I-labeled mAb 14C5 and planar gamma imaging were done in nude mice bearing an A549 (non-small cell lung carcinoma) or a LoVo (colon carcinoma) tumor. RESULTS: Internalization studies with both A549 and LoVo cells showed that 125I-labeled mAb 14C5 is slowly internalized with approximately 30% of the initially bound mAb 14C5 internalized after 2 hours at 37 degrees C. Internalization of mAb 14C5 could be visualized with confocal laser scanning microscopy. In vivo, radioisotope uptake peaked at 24 hours for both tumor models (n = 5) with no significant difference in percentage of injected dose/g tissue (A549 10.4 +/- 0.8 and LoVo 9.3 +/- 0.8). Via planar gamma camera imaging, A549 lung tumors as well as LoVo colon tumors could be clearly visualized. CONCLUSIONS: The in vitro and in vivo targeting properties of 123I- and 131I-labeled mAb 14C5 are promising and could provide a new antibody-based agent for radioimmunodetection and radioimmunotherapy of patients bearing antigen 14C5-expressing tumors.     

肺癌组织中HIF-1α的表达及低氧条件下A459细胞miR-15a的表达

目的:研究肺癌组织中缺氧诱导因子-1α的表达以及A549肺癌细胞在常氧和低氧条件下miR-15a的表达。方法:取30例肺癌患者的石蜡切片组织样本(其中有肺癌的组织及其相对应正常肺组织）,进行苏木精-伊红染色和免疫组化染色来观察肺癌组织和正常肺组织HIF-1α染色的强弱程度。将A549细胞分别在培养条件为37℃、5％CO2的常氧条件下和培养条件为37℃、5％CO2、1％O2的低氧条件下培养48h 后通过实时荧光定量PCR技术来检测miR-15a的表达。结果:HIF-1α主要在肺癌细胞胞核及细胞质中表达,呈棕黄色颗粒状,有明显的异质性,肿瘤间质细胞也可见少量表达。癌旁正常的肺组织无 HIF-1α的表达。在30例肺癌组织中,有8例HIF-1α表达为（-）,7例表达为（+）,9例表达为（++）,6例表达为（+++）,阳性率为73%。miR-15a在正常氧条件下培养的A549细胞中相对表达量为1.82546±1.62784,在低氧条件下培养的A549细胞相对表达量为0.17598±0.11046。MiR-15a在低氧条件下培养的A549细胞中表达量低于在常氧条件下培养的A549细胞中的表达量。结论:肺癌组织中HIF-1α高表达,而正常肺组织中无HIF-1α的表达。表明肺癌中存在着缺氧微环境。在低氧状态下培养48h的肺癌A549细胞与常氧状态下培养48h的A549细胞比较,miR-15a的表达是明显下调的,表明在缺氧时肿瘤细胞中miR-15a的表达是下调的,也提示miR-15a可能作为一个肺癌早期筛查、早期诊断的生物学标志物,并为肺癌靶向治疗提供线索。     

凋亡肿瘤细胞致敏的树突状细胞疫苗治疗肺癌的实验研究

目的：用凋亡肿瘤细胞致敏的树突状细胞（dendritic cells，DCs）激发肿瘤抗原特异性的细胞毒T细胞（cytotoxic T lymphocytes，CTL）活性，观察其体内外抗肺癌的特性。方法：常规方法从健康人外周血单个核细胞中诱导DCs，采用或不采用凋亡肿瘤细胞负载DCs，并利用激发型CD40单克隆抗体（CD40mAb）诱导DCs成熟；成熟DCs与自体T细胞共育，分别获得Ag-CTL及non-Ag-CTL，流式细胞仪检测Ag-CTL细胞表型的变化；^3H-TdR掺入法测定DNA片段形成率；建立人肺癌细胞株A549荷瘤裸鼠模型，过继回输Ag-CTL和non-Ag-CTL，评价其在体内的抗肿瘤活性。结果：CD40mAb激发可使DCs上调CD1a、CD80、CD86、CD83、HLR-DR的表达；凋亡肿瘤细胞负载联合CD40mAb激发可进一步促进DCs的成熟；成熟DCs和自体的T细胞共育活化后CD8^＋T细胞明显上调；Ag—CTL对A549具有高效特异的杀伤力，明显强干Ag-CTL对肝癌细胞株HepG2的作用（P〈0．01），且Ag-CTL对A549的杀伤力明显强于non—Ag-CTL（P〈0．01），而non-Ag-CTL对A549及HepG2细胞的杀伤力无显著性差异；体内实验表明，Ag-CTL可有效抑制裸鼠皮下移植瘤的生长，与生理盐水组（NS组）、non-Ag-CTL组相比在统计学意义上有显著差异（P〈0．05），non-Ag-CTL组与NS组相比在统计学意义上有差异（P〈0．05）。结论：凋亡肿瘤细胞致敏的树突状细胞疫苗激发的Ag—CTL在体内外均呈现抑制肺癌细胞的特性。     

Prognostic significance of blood group antigen expression of tumor tissue in lung cancer patients

AIMS AND BACKGROUND: Many prognostic factors have been evaluated both for SCLC and NSCLC. The prognostic significance of blood group antigen expression of tumor tissues has been studied particularly in NSCLC, yielding divergent results. The aim of the present study was to investigate the prognostic value of the tumoral expression of blood group antigens ABH in lung cancer. METHODS: The presence of blood group antigens was assessed immunohistochemically in paraffin-embedded tumor samples from 92 patients diagnosed between 1996 and 1997. Monoclonal antibodies were used to detect blood group antigens. RESULTS: The median survival was longer in NSCLC patients whose tumors were positive for blood group antigen A (P = 0.009). Since the expression of blood group antigen A in tumor cells was limited to patients with type A or AB blood, survival analysis of these patients showed survival to be longer in non-small cell lung cancer patients with blood group antigen A-positive tumors (P= 0.0019). CONCLUSIONS: Expression of blood group antigen A in tumor cells is an important, favorable prognostic factor in patients with non-small cell lung cancer, which could be useful to stratify patients with blood group A or AB according to possible outcome, and to guide therapeutic decision-making. The expression of blood group antigens ABH should be evaluated in larger series of lung cancer patients (including small and non-small cell lung cancer) with all blood types.