胃癌组织HLA－I类和DR分子免疫组化研究

本文应用免疫组化法对６４例胃癌、癌旁组织和６例胃溃疡大致正常胃粘膜冰冻和石蜡切片进行了染色．结果表明，正常胃粘膜和癌旁胃粘膜上皮细胞ＨＬＡ－Ｉ类分子表达阳性，其着色较均一，ＨＬＡ－ＤＲ染色均阴性．胃癌细胞Ｉ类分子表达缺失（２７／６４例），与癌旁上皮比较差异显著（Ｐ＜０．０１）。粘液细胞癌和低分化癌Ｉ类分子缺失率显著高于高分化癌（Ｐ＜０．０２５）．此外，发生肿瘤转移的病例Ｉ类分子缺失率（１２／１５例）显著高于无转移组（１／５例，Ｐ＜０．０２５）．ＤＲ分子在癌组织表达阳性，其阳性率高达５３．１％（３４／６４例）．低分化癌ＤＲ分子阳性率亦显著高于高分化癌和中分化癌，未分化癌ＤＲ分子阳性率亦显著高于高分化癌（Ｐ＜０．０１～０．０５）．提示（１）ＨＬＡ－Ｉ类分子表达缺失可能与癌细胞逃避宿主免疫监视发生润浸生长和转移有关；（２）分化程度不同的癌组织ＨＬＡ－Ｉ类分子表达差异显著，提示癌细胞分化可能影响Ｉ、Ⅱ类分子表达和肿癌抗原呈递；（３）ＨＬＡ－Ｉ类和ＤＲ分子表达异常可能是上皮恶性转变的标志之一．     

4种癌基因mRNA在胃癌组织中的表达及意义

应用原位分子杂交（ＩＳＨ）技术，检测８８例胃癌组织中Ｋ－ｒａｓ、Ｈ－ｒａｓ、Ｃ－ｍｙｃ和肿瘤转移抑制基因ｎｍ２３（Ｈ１）ｍＲＮＡ．其阳性结果分别为７８．４％、７０％、５８％和３８．６％，胃癌癌旁移行区正常粘膜和正常胃粘膜上皮的阳性率分别为１８．２％、１７％、１９．３％、２１．６％和０、０、０、３／５，与肿瘤区相比较，除ｎｍ２３外差异均非常显著（Ｐ＜０．０１）。Ｋ－ｒａｓ、Ｈ－ｒａｓｍＲＮＡ表达在在细胞膜内侧，Ｃ－ｍｙｃｍＲＮＡ主要表达在细胞核内，ｎｍ２３－Ｈ１ｍＲＮＡ表达在胞浆内。４种癌基因表达与组织学类型无关，ｎｍ２３－Ｈ１的表达与胃癌病人有无淋巴结转移有关（Ｐ＜０．０１）。     

套式PCR和原位杂交技术检测肝病患者单个核细胞？…

目的 了解慢性乙型肝炎（中度）和原发性肝癌（ＨＢｓＡｇ阳性）患者ＰＢＭＣ内ＴＴＶ ＤＮＡ存在情况。方法 采用套式ＰＣＲ以及原位杂交技术检测外周血单个核细胞（ＰＢＭＣ）内ＴＴＶ ＤＮＡ。结果 套式ＰＣＲＳＷＩＭ２６例慢性乙型肝炎（中度）患者ＰＢＭＣ内ＴＴＶ ＤＮＡ阳性７例。阳性率２６．９％,非常显著高于健康对照（Ｘ＾１２＝１４．３,Ｐ〈０．００１）;２１例原发性肝癌（ＨＢｓＡｇ阳性）虱ＰＢＭＣ内ＴＴ     

c-met蛋白表达与胃粘膜病变的关系及预后意义

目的 研究ｃ－ｍｅｔ蛋白在胃粘膜病变演进过程中的表达及关系,探讨ｃ－ｍｅｔ表达对胃癌预后的意义。方法 对１６９例经病理证实的不同胃粘膜病变采用免疫组织化学ＳＰ法检测ｃ－ｍｅｔ蛋白表达,用Ｋａｐｌａｎ－Ｍｅｉｅｒ法的Ｌｏｇ－ｒａｎｋ检验胃癌生存率。结果 在浅表性胃炎、萎缩性胃炎、肠化生、异型增生、早期胃癌和进展期胃癌中,ｃ－ｍｅｔ蛋白表达率分别为２３．５％（４／１７）,３６．８％（１４／３８）,５１．５％（１７／３３）,６１．３％（１９／３１）,６６．７％（８／１２）和７３．７％（２８／３８）,而且肠化生、异型增生、胃癌均显著高于浅表性胃炎（Ｐ〈０．０５）。胃粘膜增殖程度与ｃ－ｍｅｔ阳性表达强度密切关系分析,两者有显著关联（Ｐ〈０．０１）。ｃ－ｍｅｔ阳性表达与胃癌组织类型、浆膜浸润和淋巴结转移密切相关,而且Ｂｏｒ     

慢性肾功能衰竭患者血小板胞浆游离钙浓度及血栓素B2？…

用Ｆｕｒａ－２荧光测定法和ＲＩＡ，对２４例慢性肾功能衰竭（ＣＲＦ）维持血透患者（男１６例，女８例，年龄２６￣７１岁，平均５０．９岁）血小板的胞浆游离钙浓度和血栓素Ｂ２（ＴＸＢ２）含量进行了测定。ＣＲＦ组透析前、后血小板胸浆游离钙浓度均高于正常对照组（Ｐ均〈０．００１），透析后低于透析前（Ｐ〈０．００２）；透前、后血小板ＴＸＢ２均低于正常（Ｐ分别小于０．００１和０．０５），管析后高于透析前（Ｐ〈０．     

良、恶性鼻咽活检组织中EB病毒DNA检测、EBNA的分型及表达

应用ＥＢ病毒ＤＮＡＢａｍＨＩＷ片段、ＥＢＮＡ一２Ａ、Ｂ型分了探针，检测我区鼻咽癌（包括鼻咽原位癌）、临床高度怀疑鼻咽癌（包括鼻咽上皮细胞非典型增生、颈淋巴结肿大及鼻咽结节）和慢性鼻咽炎等活检组织共９６例。各组均以Ａ型病毒感染为主：鼻咽癌组阳性为２７／３５（７７．１％）；临床疑癌组７／１０（７０．０％）；慢性鼻咽炎织１８／２７（６６．７％）。Ｗ和Ａ型均阳性的鼻咽癌组为２０／２９（６９．０％）；非癌组为８／２５（３２．０％）。同时用抗补体免疫荧光法检测ＥＢＮＡ的表达，鼻咽癌组阳性为１９／２０（９５．０％），而慢性炎组为１／１５（６．７％）。以ＥＢ病毒ＤＮＡＢａｍＨＩＷ片段、ＥＢＮＡ一２Ａ型片段和ＥＢＮＡ表达检测中任一项阳性作为ＥＢ病毒感染、整合或表达的依据，则鼻咽癌组与非癌组之间有明显的差别（Ｐ＜０．００１）。这从另一角度提示ＥＢ病毒（特别是ＥＢＮＡ一２Ａ型）感染与我区鼻咽癌病因、发病有密切关系。     

p53和nm23联合表达对食管鳞癌淋巴结转移的影响

目的：探讨ｐ５３ 和ｎｍ２３ 表达作为食管鳞癌转移标志物的实用价值。方法：采用免疫组化方法检测８５ 例原发性食管鳞癌中ｐ５３ 和ｎｍ２３ 蛋白表达。结果：６３－５３ ％ （５４／８５） 肿瘤呈ｐ５３ 阳性表达,ｐ５３ 阳性表达与肿瘤淋巴结转移和ＴＮＭ 分期有关（Ｐ值均为０－００１）。４０ ％（３４／８５） 肿瘤为ｎｍ２３ 低表达。ｎｍ２３ 低表达与肿瘤浸润深度、淋巴结转移、ＴＮＭ 分期有关（ Ｐ值分别为０－０３２、０－００１、０－００１） 。单因素分析显示：ｐ５３ 和ｎｍ２３ 表达为影响淋巴结转移的主要因素（ ＯＲ值分别为６－９８４ 和０－０８７,Ｐ＜０－００１）。多因素分析显示：ｎｍ２３ 表达是影响淋巴结转移的一个独立因素（珘ｂ＝ － ０－８４８１ , ＯＲ＝ ０－１８１, Ｐ＝ ０－０００１） 。ｐ５３阳性肿瘤具有高度淋巴结转移的倾向（珘ｂ＝ ０－３１５０, ＯＲ＝２－２８４,Ｐ＝ ０－０５６５）,其它临床病理学参数与淋巴结转移之间未见明显关系（Ｐ＞ ０－０５） 。ｐ５３ 和ｎｍ２３ 异常表达之间呈负相关（ｒｓ＝ － ０－３８４９ ,Ｐ＝ ０－０００３）,在促进肿瘤的进展和转移过程中起联合作用。结论：ｐ５３ 和ｎｍ２３ 联合表达对判断食管鳞癌患者     

乳腺癌层粘连蛋白受体表达与微血管密度和转移及复 …

目的：探讨乳腺癌层粘连蛋白受体（ＬＮ－Ｒ）与间质微血管密度和肿瘤转移、复发的关系及意义。方法：应用免疫组化ＬＳＡＢ法检测７３例乳腺癌ＬＮ－Ｒ,ＦⅧＡｇ的表达,并对２８例病人进行随访分析。结果：ＬＮ－Ｒ的表达程度与乳腺癌淋巴结转移存在正相关（Ｐ〈０．０００１）,与病理分级无关（Ｐ〉０．０５）,与乳腺癌间质微血管密度（ＭＶＤ）存在正相关（Ｐ〈０．０００１）。淋巴结转移阳性组其ＭＶＤ值明显高于阴性组（Ｐ     

内源性E2,EGFR,PCNA在大肠癌中作用及其相互关系

目的：明确内源性雌激素（Ｅ２）和相生长因（ＥＧＦＲ）在大肠癌中的作用及相互关系，方法；免疫组化检测４８例大肠癌内源性Ｅ２ＥＧＦＲ和ＰＣＮＡ的表达。结果：内源性Ｅ２阳性２９（６０．４％）例，其阳性细胞平均百分率为４１．１％，与肿瘤淋巴结转移呈负相关（Ｐ〈０．０５），ＥＧＦＲ过表达３２（６６．７％）例，ＰＣＮＡ增殖指数高，且两者均与肿瘤淋巴结转移呈正相关（Ｐ〈０．０５），内源性Ｅ２阳性细胞百分率与ＥＧ     

可溶性白介素2受体测定对结核性胸腹水鉴别诊断的价值

用ＥＬＩＳＡ方法检测结核性和非结核性（癌性及漏出液）胸水及血清中的可溶性白细胞介素２受体（ｓＩＬ－２Ｒ）。结果显示：结核组ｓＩＬ－２Ｒ水平明显增高（２４６４±１００１Ｕ／ｍｌ），与癌性胸腹水组（７５２±４１８Ｕ／ｍｌ）及漏出液组（４１０±３１５Ｕ／ｍｌ）比较有显著性差异（Ｐ＜０．００１）。与胸水中腺苷脱氨酶活性（ＡＤＡ）呈正相关（ｒ＝０．６８８，Ｐ＜０．００１）。敏感性及特异性均为９０％以上。提示用本法检测胸腹水的ｓＩＬ－２Ｒ对于结核性胸腹水的诊断及鉴别诊断有重要意义。     

Expression of urokinase-type plasminogen activator,its receptor,and its inhibitor in gastric adenocarcinoma tissues.

The plasminogen and plasmin system, which is mainly regulated by urokinase-type plasminogen activator (uPA), its receptor (uPAR) and its inhibitor (PAI-1), is generally believed to play a role in cancer invasion and metastasis. This study was conducted to investigate the role of uPA, uPAR and PAI-1 in the invasion and metastasis of gastric adenocarcinoma. The expression of mRNAs for uPA and PAI-1 was determined by Northern blot analysis in nine primary gastric cancer tissues, nine paired metastatic lymph nodes and normal gastric mucosa. The mRNA of uPA was not or faintly detected in normal mucosa, while the expression was increased in both primary gastric cancer tissues and metastatic lymph nodes to a similar degree. The mRNA expression for PAI-1 in the gastric cancer tissues was not different from that in the paired metastatic lymph nodes and normal mucosae. uPAR was determined by immunohistochemical staining, demonstrating that five (56%) and six (67%) out of nine primary gastric cancer tissues and nine paired metastatic lymph nodes were positive, respectively and the intensity was stronger in metastatic lymph nodes. The results support the concept that most gastric cancer cells may have an innately moderate level of uPA and uPAR, and that increase of uPAR expression can be considered to be closely associated with cancer invasion and metastasis.     

胃癌中uPA、PAI-1表达及其与血管生成的关系

目的 观察胃癌组织中uPA、PAI-1mRNA及蛋白的表达，并探讨它们与肿瘤分化、血管生成及临床病理因素之间的关系。方法 用原位杂交及免疫组化S-P法检测110例胃癌组织中uPA、PAI-1的表达，根据CD34阳性的血管内皮细胞计数肿瘤组织微血管密度（MVD）。结果 （1）胃癌组织中uPA mRNA和蛋白、PAI-1 mRNA和蛋白阳性表达定位于胞质；uPA的表达随分化程度的降低有逐渐升高的趋势，PAI-1的表达随分化程度的降低有逐渐降低的趋势。（2）110例uPA mRNA及蛋白表达阳性组MVD值显著高于阴性组，差异均具有显著性（P值均＜0．05）。（3）uPA mRNA及蛋白的表达与临床分期呈正相关（P＜0．05），PAI-1的表达与临床分期和淋巴结转移无相关性。（4）uPA mRNA／蛋白与PAI-1 mRNA／蛋白的表达无相关性。结论uPA与促进胃癌的血管生成密切相关，阻断uPA的分泌和作用途径有望对胃癌浸润转移起抑制作用；胃癌组织中PAI-1可能担当重要的调节剂或者是肿瘤细胞防止自身降解的保护剂而不是这个系统的单纯抑制剂。     

c-erbB-2、VEGF和组织蛋白酶D在胃癌中的表达及其相关性

目的：探讨癌基因c-erbB-2、血管内皮生长因子（VEGF）和组织蛋白酶D（Cath-D)在胃癌中的表达及其与胃癌生物学行为的关系。方法：采用免疫组织化学（S－P）法，检测了102例胃癌手术标本中c-erbB-2、VEGF及Cath-D的表达，同时观察了网状纤维分布与c-erbB-2、Cath-D之间的关系，并将检测结果与跟踪随访资料进行了综合分析。结果：102例胃癌组织中c-erbB-2表达阳性率为38.24%（39／102），与胃癌浸润深度（P＜0.05）、淋巴结转移（P＜0.05）密切相关；VEGF表达阳性率为50％（51／102），与胃癌浸润深度（P＜0.01）、生长方式（P＜0.01）、淋巴结转移（P＜0.01）密切相关；Cath-D表达阳性率为81.37%(83/102)，与胃癌浸润深度（P＜0.05）、生长方式（P＜0.05）、淋巴结转移（P＜0.05）及脉管内有无癌栓（P＜0.05）有关。对生存期分析显示：Cath-D、VEGF、c-erbB-2阳性患者预后差，5年生存率低于阴性表达患者。结论：c-erbB-2、VEGF及Cath-D与胃癌的生长、浸润、转移、预后有密切关系，可作为判断胃癌生物学行为和预后的重要指标。     

乳腺癌组织中uPA、uPAR及nm23-H1的表达

目的　观察乳腺癌组织中uPA、uPAR、nm2 3 H1的表达并探讨与腋窝淋巴结转移的关系。方法　用免疫组化EnVi sion两步法检测 6 9例乳腺癌组织中uPA、uPAR和nm2 3 H1表达的分布情况 ,观察其与肿瘤的分化程度以及与腋窝淋巴结转移的关系。结果　 (1)uPA阳性表达定位于癌细胞胞质 ;uPAR和nm2 3 H1阳性表达定位于癌细胞胞膜及胞质 ,多数癌旁乳腺上皮细胞呈nm2 3 H1阳性表达 ;高分化乳腺癌 (Ⅰ级 )uPA和uPAR表达阳性率 (30 0 %和 2 5 0 %)低于中低分化乳腺癌 (Ⅱ、Ⅲ级 ) (分别为 6 8 1%、72 7%和 70 0 %、74 1%) (P <0 0 5 ) ;nm2 3 H1表达阳性率在乳腺癌组织不同分化程度间差异无显著性 (P >0 0 5 ) ;(2 )腋窝淋巴结有转移者uPA和uPAR的表达阳性率 (73 2 %和 75 6 %)高于无淋巴结转移者 (35 7%和35 7%) (P <0 0 5 ) ;有腋窝淋巴结转移者nm2 3 H1的表达阳性率 (2 4 4 %)显著低于无淋巴结转移者 (5 0 0 %) (P <0 0 5 ) ;uPA、uPAR和nm2 3 H1的表达与淋巴结转移的个数均无关 ;(3)uPA阳性表达的癌组织其nm2 3 H1表达阳性率 (15 0 %)低于uPA阴性表达的癌组织 (6 2 1%) (P <0 0 5 )。结论　uPA和uPAR的高表达与乳腺癌腋窝淋巴结转移密切相关 ;uPA、uPAR和nm2 3 H1可以作为乳腺癌侵袭与淋巴结转移的     

Clinicopathologic Characteristics and Prognosis of Advanced Gastric Cancer Simulating Early Gastric Cancer

Background

Although the clinicopathologic features and prognosis of Borrmann type advanced gastric cancer has been well characterized, those of advanced gastric cancer simulating early gastric cancer (AGC simulating EGC) still remains unclear.

Methods

We reviewed 1985 gastric cancer patients who had undergone gastrectomy at our hospital to determine the clinicopathologic characteristics, susceptible sites for lymph node metastasis, and prognosis of AGC simulating EGC in comparison with Borrmann type advanced gastric cancer.

Results

Among 102 patients with AGC simulating EGC, 100 patients (98%) had tumors with depressed type appearance. The frequencies of serosal invasion, lymph node metastasis, lymphatic vessel invasion, blood vessel invasion, and liver metastasis were significantly lower in AGC simulating EGC than in Borrmann type tumors. The prognosis of AGC simulating EGC was significantly better than that of the Borrmann type tumors. Multivariate analysis indicated that the gross appearance was an independent prognostic factor. In patients with AGC simulating EGC which invaded to the the muscularis propria (MP), most lymph node metastasis was restricted with the perigastric lymph nodes (1st-titer lymph nodes) and lymph node metastasis to 2nd-titer lymph nodes was only observed at station 8a.

Conclusion

AGC simulating EGC is less advanced in comparison with Borrmann type advanced gastric cancer. Based on the results of susceptible sites for lymph node metastasis in the current study, limited lymph node dissection could be indicated for AGC simulating EGC whose depth of invasion is MP.     

紧密连接蛋白1 mRNA和蛋白表达与胃癌侵袭转移及预后的相关性

目的 探讨紧密连接蛋白1(ZO-1)mRNA及蛋白表达在胃癌侵袭转移及预后中的意义.方法 Real-time qPCR法检测52例胃腺癌细胞ZO-1 mRNA表达,组织芯片SP免疫组织化学法检测228例胃腺癌细胞ZO-1蛋白表达定位变化情况.结果 81.1%的胃癌组织出现不同程度的ZO-1胞膜表达异位至胞质迷离表达的现...     

Tiam1表达与胃癌侵袭转移关系的临床和实验研究

目的检测T淋巴瘤侵袭转移诱导因子1(Tiam1)在正常胃黏膜组织、胃癌组织以及胃癌细胞系中的表达,探讨其与胃癌侵袭转移的关系。方法(1)应用免疫组化SABC法检测60例胃癌及正常胃黏膜组织中Tiam1蛋白的表达并分析其与胃癌临床病理参数间的关系。(2)应用逆转录PCR和SABC免疫组化技术分别检测Tiam1mRNA与蛋白在胃癌MKN45细胞(MO)及其高(MH)、低(ML)侵袭转移亚株中的表达,分析其与胃癌细胞侵袭转移能力的关系。结果(1)Tiam1蛋白在正常胃黏膜组织中阴性表达显著低于癌组织(0vs78.3%),两者差异有统计学意义(P<0.01),且随胃癌组织分化程度的降低、浸润深度的增加、TNM分期的升高及伴有淋巴结转移,Tiam1蛋白染色阳性率逐渐升高,差异有统计学意义(P<0.05)。但Tiam1蛋白表达水平与胃癌患者的性别、年龄、部位及癌肿大小无关,差异无统计学意义(P>0.05)。(2)Tiam1mRNA和蛋白在胃癌MKN45细胞高侵袭转移亚株中的表达均较其在MKN45细胞及低侵袭转移亚株中的表达为强,差异有统计学意义(P<0.05)。结论Tiam1表达与胃癌侵袭转移能力呈正相关,且其有可能成为反映胃癌恶性生物学行为的一种新型标志物。     

Evaluation of lymphatic invasion in primary gastric cancer by a new monoclonal antibody, D2-40

Lymphatic invasion is known as an independent predictor of lymph node metastasis in gastric cancer. However, the diagnosis of lymphatic invasion is sometimes difficult by hematoxylin-eosin (H&E) staining. Immunostaining using D2-40 was performed to study the distribution of lymphatic vessel and lymphatic invasion in a series of 78 primary gastric cancers. D2-40 showed specific staining for the lymphatic vessels, but not for blood vessels. The lymphatic invasion was most frequently found in the upper half of submucosal layer. Positive rate of lymphatic invasion by H&E staining was 27% (21/78), and that by D2-40 was 44% (34/78). Lymphatic invasion on H&E staining was diagnosed as false negative in 17 (21.8%) of 78 primary gastric cancers and false positive in 4 (5.1%) of 78 primary gastric cancers. Sensitivity for lymph node metastasis by the lymphatic invasion diagnosed by D2-40 was significantly higher (89%, 24/27) than by H&E staining (41%, 11/27). These results suggest that the diagnosis of lymphatic invasion by D2-40 is more sensitive than H&E staining. Sensitivity for the prediction of lymph node metastasis from the lymphatic invasion status in primary tumor by D2-40 was significantly higher than by H&E staining. Based on our results, we recommend the use of D2-40 immunoreactions for the routine evaluation of lymphatic invasion in gastric cancer.     

EGFR、COX-2及P63蛋白表达与甲状腺乳头状癌侵袭转移的关系

目的　探讨甲状腺乳头状癌 (PTC)中表皮生长因子受体 (EGFR)、环氧化酶 2 (COX 2 )和 p6 3蛋白的表达与肿瘤侵袭转移的关系。方法　采用免疫组化S P法检测 6 7例PTC(其中腺内侵袭 4 1例、腺外侵袭 2 6例 ;有淋巴结转移 2 9例、无淋巴结转移 38例 )、3例滤泡癌和 15例甲状腺腺瘤中EGFR、COX 2及 p6 3蛋白的表达。结果　EGFR、COX 2和 p6 3蛋白在PTC组织中的阳性表达率分别为 88 1%、82 1%和 70 2 % ,均显著高于甲状腺腺瘤 (P <0 0 5 ) ;EGFR与COX 2、COX 2与p6 3蛋白在PTC组织中的的表达呈明显正相关 (P <0 0 5 ) ;EGFR和COX 2在PTC腺外侵袭组和有淋巴结转移组阳性表达率均明显高于腺内侵袭组和无淋巴结转移组 (P <0 0 5 ) ,p6 3蛋白阳性表达率与淋巴结转移有关 (P <0 0 5 )、与浸润程度无关。结论　EGFR与COX 2在PTC组织中的高表达可能促进肿瘤的侵袭和转移 ,p6 3蛋白在PTC的高表达提示其与PTC的细胞增殖相关     

Prognostic relevance of urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitors PAI-1 and PAI-2 in gastric cancer

Expression of urokinase-type plasminogen activator (uPA), plasminogen activator inhibitor-1 (PAI-1) and plasminogen activator inhibitor-2 (PAI-2) was evaluated in 125 surgically resected gastric cancers by immunohistochemical analysis. Tissue was stained immunohistochemically with a monoclonal antibody against human uPA and monoclonal antibodies against human PAI-1 and PAI-2. In addition, DNA ploidy patterns were determined by cytofluorometer after staining with propidium iodide. We found that 82 (66%) of the 125 gastric cancers expressed uPA as diffuse cytoplasmic staining, as intensely outlined luminal borders. PAI-1 expression was observed in 62 (50%) of 125 gastric cancer as a fine, diffuse and granular pattern in the cytoplasm. PAI-2 expression was observed in 65 (52%) of the 125 gastric cancers as a diffuse cytoplasmic staining. uPA-positive tumours showed a higher incidence of infiltration, lymph node metastasis and peritoneal dissemination than uPA-negative ones. Patients with uPA-positive tumours proved to have a significantly poorer prognosis than those with negative ones. PAI-1-negative tumours showed a higher incidence of liver metastasis and carried a poorer prognosis than PAI-1-positive ones. There was no significant correlation between uPA or PAI-1 expression and DNA ploidy patterns. Conversely, there was no significant relationship between PAI-2 expression and clinicopathological parameters and prognosis. According to the expression of uPA and PAI-1 status, groups of 19 uPA(–)/PAI-1(–), 44 uPA(+)/PAI-1(–), 23 uPA(–)/PAI-1(+) and 39 uPA(+)/PAI-1(+) were subdivided. Tumours with UPA(+)/PAI-1(–) had a significantly higher incidence of liver metastasis, lymph node metastasis and serosal invasion than the other groups of tumours. Patients with uPA(+)/PAI-1(–) tumours had a significantly poorer prognosis than those with uPA(–)/PAI-1(+) tumours. These results indicate that uPA expression is a useful biological prognostic indicator, and that uPA and PAI-1 may play an important part in the tumour progression and metastasis in gastric cancer.