Distribution of Transforming Growth Factor-β and Its Receptors in Gastric Carcinoma Tissue

The distribution of the three mammalian isoforms of transforming growth factor (TGF)-β (TGF-β1,-β2, and -β3) as well as their signaling receptors, TGF-β type I and type II receptors (TβR-I and TβR-II, respectively), in gastric carcinoma tissue was examined by immunohistochemistry using specific antibodies. Tissue specimens were obtained from 25 cases of gastric carcinoma, which were classified into two groups according to Lauren's classification, i.e. 15 cases of diffuse carcinoma and 10 cases of intestinal carcinoma. In normal gastric mucosa apart from carcinoma nests, all of TGF-β1, -β2, -β3, TβR-I and TβR-II were clearly demonstrated in fundic glands. In sharp contrast, none of them was detectable in surface mucous cells. In carcinoma cells, strong staining for TGF-β1, -β2 and β3 was obtained only in diffuse-type carcinoma. In particular, carcinoma cells scattered as single cells or small nests had a tendency to show strong staining for TGF-βs. The receptors tended to be distributed concomitantly with the ligands, and diffuse-type carcinoma showed stronger receptor staining than intestinal-type carcinoma. In cancer stroma, TGF-βs and receptors were detected in both diffuse and intestinal types, but the area with positive staining was wider and more dispersed in diffuse-type carcinoma than in intestinal carcinoma. These results suggest that TGF-β may contribute in part to the variety of histogenesis and mode of progression of gastric carcinoma.     

Detection of Active Form of Transforming Growth Factor-β in Cerebrospinal Fluid of Patients with Glioma

We examined transforming growth factor-β (TGF-β) activity in cerebrospinal fluid of 39 patients with various brain tumors, and found it in 10 glioma cases that had lesions related to subarachnoid space or ventricle. In one glioma case, TGF-β detected on admission disappeared after radiation and chemotherapy. We confirmed that five glioma cell lines produced TGF-β, and that four of them produced active form of TGF-β directly. The active form of TGF-β was also identified from cerebrospinal fluid before the acidification treatment in two cases. The calculated contents were 110 ng/ml and 18 ng/ml. These results indicate that active form of TGF-β is directly produced by tumor cells in patients with glioma, and may contribute to immunodeficiency of the host.     

神经酰胺通过非p53途径诱导鼻咽癌细胞中p21WAF1的表达

[目的]探讨第二信使神经酰胺信号传导诱导鼻咽癌细胞p21^WAF1表达的机理。[方法]Western blot法检测p53,p21,Jun,NFкB基因表达,试剂盒检测SAPK/JNK的活性。[结果]在鼻咽癌CNE2细胞中阿霉素能刺激p53表达,不能上调p21^WAF1的表达,可见在CNE2细胞中p53为功能异常型,C2-神经酰胺处理CNE2细胞后,可见p53蛋白呈现下降趋势;而p21^WAF1蛋白在处理4、16小时时,p21^WAF1表达明显增高,但36小时后p21^WAF1恢复到基础水平,在6.25μmmol/L,12.5μmmol/L,25μmmol/L的C2-神经酰胺处理24小时后p21^WAF1上升,而50μmmol/L的C2-神经酰胺处理24小时后,p21^WAF1开始下降,C2-神经酰胺处理CNE2细胞2小时后,JNK的活性开始增加,6小时时保持激活状态,12小时时下降,c-Jun/AP1蛋白在神经酰胺处理后3小时开始明显增高,持续到12小时,24小时下降至基础水平;C2-神经酰胺对CNE2细胞中NFкB蛋白表达没有明显的变化。[结论]C2-神经酰胺在鼻咽癌细胞CNE2中,通过p53非依赖性途径诱导p21^WAF1的表达,神经酰胺激活JNK,从而激活AP-1因子,可能是其诱导p21^WAF1表达的机理。     

Potentiation of Metastatic Capacity by Transforming Growth Factor-β1 Gene Transfection

This study was designed to assess whether the excessive secretion of transforming growth factor-β1 (TGF-β1) by Chinese hamster ovary (CHO) cells transfected with TGF-β1 gene may be linked to the development of a metastatic phenotype. We observed large numbers of metastatic colonies in the lungs of nude mice inoculated with the transfected CHO cells. The tumors derived from these transfected cells demonstrated marked angiogenesis. We postulate that the overproduction of TGF-β1 by these tumors may participate in the metastatic progression following establishment of angiogenesis at the primary tumor site.     

Elevated Levels of Plasma Transforming Growth Factor-β in Patients with Hepatocellular Carcinoma

We measured the plasma transforming growth factor-β (TGF-β) concentration in 14 patients with human hepatocellular carcinoma (HCC) and 9 age-matched normal subjects using growth inhibition assay of mink lung epithelial cells. The calculated plasma TGF-β concentration in the patients with HCC was 28.6 ± 27.9 ng/ml (mean± SE), showing significant elevation compared with that in 9 normal subjects (5.3 ± 3.3 ng/ml, P<0.01). In three cases, we could measure plasma TGF-β levels before and after their treatment for HCC. The plasma TGF-β levels decreased from 59.0 to 18.2 ng/ml after hepatic resection in one case, and from 24.0 to 10.7 ng/ml and from 12.4 to 3.4 ng/ml after transhepatic arterial embolization in the other two cases. These data indicate that plasma TGF-β level is elevated in patients with HCC, probably due to release from HCC tissues.     

Mutations and Reduced Expression of the Transforming Growth Factor-β Receptor II Gene in Rat Lung Adenocarcinomas Induced by N-Nitrosobis-(2-hydroxypropyl)amine

Mutations and expression of the transforming growth factor-β receptor type II (TGF-βRII) gene were investigated in lung adenocarcinomas induced by N -nitrosobis(2-hydroxypropyl)amine (BHP) in rats. Males of the Wistar strain, 6 weeks old, were given 2000 ppm of BHP in their drinking water for 12 weeks and then maintained without further treatment until killed at week 25. Total RNA was extracted from 12 adenocarcinomas and mutations in TGF-βRII were investigated by RT-PCR-restriction-SSCP analysis followed by sequencing analysis. Two out of 12 adenocarcinomas showed band shifts, indicative of mutations (16.7%). One was a CTG-to-TTG (Leu to Leu) transition at codon 308 without amino acid alteration and the other a frameshift deletion of one of two guanines at nucleotides 1434 to 1435 (codon 477 to 478). Semi-quantitative RT-PCR analysis demonstrated significantly reduced TGF-βRII expression in adenocarcinomas, as compared with normal lung tissue. These results suggest that TGF-βRII alterations may play a role in the acquisition of growth advantage by lung adenocarcinomas induced by BHP in rats.     

CyclinD1 c-myc和p53的表达与肝细胞癌生物学行为关系

目的:探讨肝细胞癌(Hepatocellularcarcinoma,HCC)及癌旁肝组织CyclinD1、c-myc及p53蛋白表达的意义及其与肝癌生物学行为关系。方法:采用EnVisionTMplus免疫组织化学方法检测CyclinD1、c-myc及p53蛋白在52例HCC及癌旁肝组织中的表达。结果:CyclinD1及c-myc在HCC组织中的阳性率明显高于在癌旁肝组织中的阳性率(P<0.05),在HCC中p53的阳性表达与CyclinD1、c-myc的阳性表达呈正相关(r=0.4637,P=0.0022、r=0.3445,P=0.0273,);CyclinD1、c-myc及p53在人肝癌组织中的检出率与肝外转移、术后复发及肿瘤分化程度明显有关(P<0.05),CyclinD1的检出率与门静脉癌栓明显有关(P<0.05),p53的检出率与血清AFP和TSGF水平有显著性差异(P<0.05);CyclinD1、c-myc及p53的检出率与临床分期、肿瘤大小、肿瘤个数、HBsAg状况无明显关系。结论:CyclinD1、c-myc及p53蛋白的过表达可促使肝癌细胞增殖,使肝癌细胞具有更强的侵袭力,与肝癌的发生、发展密切相关。     

p53和p21WAF1在鼻咽癌rAd-p53瘤内注射前后的表达及其与近期预后的关系

目的探讨重组人p53腺病毒(rAd-p53)瘤内注射前后鼻咽癌(NPC)组织中p53蛋白和p21WAF1蛋白的表达情况,及其与鼻咽癌近期疗效的关系。方法应用免疫组织化学法检测12例鼻咽慢性炎组织和63例确诊中晚期鼻咽癌组织的p53和p21WAF1蛋白表达情况。63例中晚期鼻咽癌随机分为2组:p53治疗组(32例):rAd-p53瘤内注射+同步放化疗;常规治疗组(31例):同步放化疗。分析两组治疗前及放疗至20 Gy时p53和p21WAF1蛋白表达情况及其与预后的关系。结果 NPC组织中p53和p21WAF1蛋白阳性表达率分别为49.21%和46.03%,和鼻咽黏膜慢性炎相比差异有统计学意义(P<0.05)。NPC组织中p53和p21WAF1蛋白表达有相关性(rs=0.556,P=0.000)。放疗前及放疗至20 Gy时,鼻咽癌p53治疗组和p21WAF1蛋白阳性表达率差异有统计学意义(P<0.05);两组p53蛋白和p21WAF1蛋白阳性表达与1年无瘤生存率有关(P<0.05)。结论 rAd-p53瘤内注射后p53和p21WAF1蛋白的阳性表达可能在抑制鼻咽癌复发或转移进程中起着重要作用,并预示较好的预后。     

GW843682X对鼻咽癌细胞中PLK1和p53表达的影响

[目的]研究Polo样激酶（PLK）抑制剂GW843682X对鼻咽癌5-8F细胞中PLK1和p53表达水平的影响。[方法]用不同浓度的GW843682X处理鼻咽癌5-8F细胞,在不同时间点倒置显微镜下观察细胞形态,RT-PCR及Western blot分别检测PLK1和p53的mRNA和蛋白表达水平的变化。[结果]GW843682X能够显著抑制5-8F细胞的增殖,呈剂量和时间依赖性。RT-PCR结果表明GW843682X可下调PLK1和p53的mRNA表达水平。Western blot结果显示GW843682X降低PLK1和p53的蛋白表达水平。[结论]GW843682X抑制鼻咽癌5-8F细胞中PLK1和p53的表达。     

鼻咽癌p53 p21 WAF1和MDM2蛋白异常表达的临床意义

目的：探讨p53、p21^WAF1、MDM2蛋白在原发鼻咽癌（NPC）异常表达的临床意义。方法：采用LSAB法检测69例原发NPC组织中p53、p21^WAF1和MDM2蛋白的表达状况。结果：1）p53、p21^WAF1和MDM2蛋白在原发NPC组织的阳性表达率分别为79．7％、84．1％、和82．6％；高表达率分别为50．7％、46．4％和31．9％。2）p53蛋白的高表达率随TNM分期的升高而增多，P＝0．042。3）p53或MDM2蛋白高表达者的复发间期显著短于相应蛋白低表达／阴性者，分别P＝0．038和P＝0．002。4）p53和MDM2蛋白同时高表达者、MDM2蛋白高表达同时p21^WAF1蛋白低表达／阴性者的复发间期明显短于对照组，分别P＜0．001；p21^WAF1蛋白高表达同时p53蛋白低表达／阴性者、p53和MDM2蛋白同时低表达／阴性者的复发间期显著长于对照组，分别P＝0．002和P＝0．014。5）p53和MDM2蛋白高表达同时p21^WAF1蛋白低表达／阴性者的复发间期明显短于对照组，P＜0．001；p53和MDM2蛋白低表达阴性同时p21^WAF1蛋白高表达者的复发间期明显长于对照组，P＝0．002。结论：p53或MDM2蛋白高表达提示有促进NPC复发的作用，p21^WAF1蛋白高表达提示有抑制NPC复发的作用。单独检测p53或MDM2蛋白在原发NPC组织的表达情况可以和为预测NPC复发倾向和临床预后的参考指标；如同时检测p53、MDM2和p21^WAF1蛋白的两项或三项指标，预测意义更理想。     

X射线照射诱导鼻咽癌细胞mdrⅠ和p53基因的表达及临床意义

目的：探讨X射线照射后鼻咽癌CNE-1细胞产生多药耐药的机制。方法：采用RT—PCR和Western blot方法，检测X射线照射后CNE-1细胞mdr1和p53基因的表达。结果：照射后细胞mdr1 mRNA和P-gp表达均增强，p53蛋白的表达也增强．并与p-gP表达呈正相关性（P〈0．05）。结论：X射线照射可诱导CNE—1细胞mdr1和p53基因的表达．两者的相互协调作用可能是照射后肿瘤细胞产生多药耐药的重要机制之一。     

Transforming Growth Factor-β and Hepatocyte Growth Factor Produced by Gastric Fibroblasts Stimulate the Invasiveness of Scirrhous Gastric Cancer Cells

Scirrhous gastric carcinoma is characterized by cancer cells that infiltrate rapidly in the stroma with extensive growth of fibroblasts. In the present study, we examined the effect of gastric fibroblasts on the invasiveness of a Scirrhous gastric cancer cell line, OCUM-2D, using an invasion assay. Gastric fibroblast-derived conditioned medium (CM) significantly stimulated the invasiveness of OCUM-2D cells, as did transforming growth factor- β (TGF- β ) and hepatocyte growth factor (HGF). The stimulating activity of gastric fibroblast-derived CM was inhibited significantly by anti-TGF- β neutralizing antibody or anti-HGF neutralizing antibody. TGF- β and HGF were detected in the gastric fibroblast-derived CM, and TGF- β receptor and C-met (HGF receptor) were expressed on OCUM-2D cells. Thus, TGF- β and HGF produced by gastric fibroblasts appear to affect the invasiveness of scirrhous gastric cancer cells. TGF- β was also detected in the conditioned medium derived from OCUM-2D cells, though HGF was not. TGF- β appears to affect the invasiveness of OCUM-2D cells in both paracrine and autocrine fashions.     

重组腺病毒载体介导的人野生型p53基因增强肝癌细胞对化疗药物的敏感性

目的： 观察表达人野生型p53,GM-CSF和B7-1基因的重组腺病毒载体（BB-102）提高肝癌细胞对化疗药物的敏感性。方法： BEL-7402,HLE和HuH-7 3株肝癌细胞被50 MOI的BB-102转染后,Western blot检测p53基因的表达,MTT方法检测肝癌细胞对化疗药物的敏感性。结果： 当MOI为50 pfu/细胞时,腺病毒载体对3株肝癌细胞的转染效率均达到80％以上。转染BB-102后,HLE和HuH-7细胞对顺铂的敏感性分别提高11倍和28倍,对丝裂霉素-C的敏感性分别提高3.75倍和20倍。而BB-102的转染对BEL-7402细胞的化疗敏感性没有影响。结论： BB-102腺病毒载体转染后能显著提高p53基因突变的HLE和HuH-7细胞对顺铂和丝裂霉素-C的敏感性,因而增强顺铂和丝裂霉素-C对HLE和HuH-7细胞的杀伤作用。     

重组腺病毒载体介导的人野生型p53基因增强肝癌细胞对化疗药物的敏感

目的：观察表达人野生型和p53,GM－CSF和B7－1基因的重组腺病毒载体（BB－102）提高肝癌细胞对化疗药物的敏感。方法：BEL－7402,HLE和HuH-73株肝癌细胞被50MOI的BB－102转染后,Western blot检测p53基因的表达,MTT方法检测肝癌细胞对化疗药物的敏感性。结果：当MOI为50pfu／细胞时,腺病毒载体对3株肝癌细胞的转染的效率均达到80％以上。转染BB－102后,LHE和HuH-7细胞对顺铂的敏感性分别提高11倍和28倍,对丝裂霉素－3的敏感性分别提高3．75倍和20倍,而BB－102的转染对BEL－7402细胞的化疗敏感性没有影响。结论：BB－102腺病毒载体转染后能显著提高p53基因突变的HEL和HuH-7细胞对顺铂和丝裂霉素－C的敏感性,因而增强顺铂和丝裂霉素－C对HLE和HuH-7细胞的杀伤作用。     

p53基因对人胃癌细胞生长及致瘤性的抑制作用

p53基因异常是人类肿瘤中最常见的基因变异之一．是最有希望用于肿瘤基因治疗的目的基因。在人胃癌组织中有较高频率的p53基因缺失和突变，为探讨p53基因用于胃癌治疗的可行性，我们采用脂质体介导方法将外源性野生型p53基因转染一株p53基因有部分缺失的人胃癌BGC823细胞，获得较高的转染效率，对转染后细胞DNA，RNA和蛋白进行分析．结果表明外源性p53基因已整合人细胞并获稳定表达，表达有外源性野生型p53基因的细胞生长速度，软琼脂集落形成率及裸鼠致瘤性均有部分抑制。这一结果进一步证明p53基因在胃癌发生发展过程中起重要作用．本研究为采用野生型p53基因转染进行胃癌基因治疗提供了细胞学实验依据。     

BAG-1在喉鳞癌组织中表达及其与p53基因和细胞凋亡的相关性

目的最近研究发现在恶性肿瘤细胞中存在BAG-1蛋白表达水平和活性异常升高。本研究探讨在喉鳞状细胞癌(laryngealsquamouscellcaicinomas,LSCC)中BAG-1表达临床意义及其与p53、细胞凋亡的关系,以了解BAG-1与喉癌发生发展及预后的关系。方法运用免疫组化技术及TUNEL法检测68例LSCC组织及30例癌旁组织中BAG-1、p53蛋白的表达及癌细胞凋亡指数(apoptosisindex,AI),并应用计算机图像分析系统对其阳性表达进行定量分析。结果BAG-1在LSCC及癌旁组织中的阳性率分别为76.5%、16.7%,BAG-1蛋白在LSCC组织的表达较癌旁组织中的表达高(P<0.05),5年生存者BAG-1蛋白表达阳性率显著低于5年死亡者(P<0.05),且细胞核BAG-1阳性者较细胞浆阳性者预后更差(P<0.05);BAG-1蛋白阳性组及BAG-1蛋白阴性组的p53蛋白阳性率差异无显著性(P>0.05);BAG-1阳性患者的AI均数显著低于阴性患者(P<0.01),且表达呈负相关(r=-0.602)。结论BAG-1可能在LSCC的细胞凋亡及肿瘤发生中起着重要作用,并对LSCC...     

p33ING1、p53在结直肠癌中的表达及其相互关系

目的：探讨p33^ING1、p53在结直肠癌中的表达及其相互关系。方法：应用免疫组化SP法检测60例结直肠癌组织及相应正常黏膜组织中p33^ING1、p53的表达。结果：结直肠癌组织、相应正常黏膜组织中p33^ING1蛋白的阳性表达率分别为43．3％（26／60）、100％（60／60）（P〈O．01），p53蛋白分别为51．6％（31／60）、0％（0／60）。p33^ING1在无淋巴结转移组及淋巴结转移组癌组织中的阳性表达率分别为57．6％（19／33）、25．9％（7／27）（P〈0．05）；在DukesA、B期、Dukes C、D期病例中分别为56．7％（17／30）、30．0％（9／30）（P〈0．05）。在p53表达阴性的29例中有12例（41．4％，12／29）p33^ING1表达缺失，而p53阳性的31例病例中有22例（71．0％，22／31）p33^ING1表达阴性（P〈0．05），在p53蛋白表达阳性的病例中p33^ING1蛋白表达明显缺失，两者表达呈负相关。结论：p33^ING1在结直肠癌组织中低表达，与p53互相协同，在结直肠癌的发生、发展中可能起重要作用。