尿脱落细胞增殖细胞核抗原mRNA检测在膀胱癌诊断中的应用价值

目的探讨尿脱落细胞增殖细胞核抗原(PCNA)mRNA检测在膀胱癌诊断中的应用价值。方法收集32例膀胱癌、52例泌尿系统良性疾病患者和10例健康志愿者清晨中、后段尿液,采用RT-PCR法检测尿脱落细胞PCNAmRNA表达,并与尿脱落细胞学检查结果比较。结果PCNAmRNA诊断膀胱癌的特异性为64%,低于尿脱落细胞学检测的88%(P<0.05),敏感性为100%,高于尿脱落细胞学检测的69%(P<0.01)。膀胱良性疾病患者、Ⅰ、Ⅱ、Ⅲ级膀胱癌患者尿脱落细胞PCNAmRNA表达强度分别为0.5128±0.0307、0.5153±0.0402、0.6560±0.0626、0.8657±0.0266。膀胱良性疾病患者与Ⅰ级膀胱癌患者间差异无统计学意义,与Ⅱ、Ⅲ级膀胱癌患者间差异有统计学意义(P<0.05)。膀胱癌患者尿脱落细胞PCNAmRNA表达强度随膀胱癌分级增加而升高(P<0.05)。浸润性膀胱癌患者尿脱落细胞PCNAmRNA表达强度高于浅表性膀胱癌患者(P<0.01),分别为0.8040±0.0807、0.5595±0.0447。结论尿脱落细胞PCNAmRNA检测在膀胱癌早期诊断、常规筛查以及术后复发监测中具有潜在的应用价值。

MCM4促进透明细胞肾细胞癌细胞增殖的研究

目的:探讨微小染色体维持缺陷蛋白4(MCM4)对透明细胞肾细胞癌(ccRCC)细胞的影响。方法:GEPIA数据库分析不同肿瘤MCM4的表达,通过免疫组化染色(IHC)检测ccRCC病理标本中MCM4的表达。将HTB-47和CRL-1932细胞均各分为实验组与对照组,利用RT-PCR、Western印迹、细胞平板克隆形成实验、CCK-8实验验证MCM4对细胞生长的影响。通过GEPIA数据库建立MCM4与增殖细胞核抗原(PCNA)共表达网络,IHC验证ccRCC中MCM4和PCNA的相关性。结果:GEPIA数据库结果显示ccRCC组织中MCM4蛋白有表达,且其高表达提示不良预后(P<0.001)。IHC显示,与正常组织相比,ccRCC肿瘤组织中MCM4表达升高。临床特征显示肿瘤大小与MCM4表达水平相关(χ^(2)=9.199,P<0.05)。在敲低MCM4基因后HTB-47和CRL-1932细胞MCM4蛋白表达下降(T=5.432、4.784,均P<0.05),细胞增殖能力降低(T=4.798、5.278、5.112、4.628,均P<0.05)。在数据库及IHC中均观察到MCM4的表达与PCNA有一致性(R=0.64,χ^(2)=8.414,均P<0.05)。结论:MCM4在ccRCC中高表达,且与不良的临床病理特征相关。敲低MCM4基因可抑制ccRCC细胞增殖,且其与PCNA基因表达高度一致。

肿瘤坏死因子对喉鳞状细胞癌细胞的增殖抑制作用

目的探讨肿瘤坏死因子(TNF)对喉鳞状细胞癌细胞的增殖抑制作用。方法选用人喉鳞癌Hep-2细胞株,分为对照组、20 pg/mL TNF-α组、50 pg/mL TNF-α组、100 pg/mL TNF-α组和200 pg/mL TNF-α组,分别采用相应药物进行处理。采用MTT法检测细胞增殖抑制率,采用流式细胞术检测细胞凋亡率和细胞周期,采用免疫组织化学法检测细胞增殖细胞核抗原(PCNA)表达水平,采用Western blot法检测细胞周期蛋白依赖性激酶4(CDK4)表达水平。结果与对照组比较,各浓度TNF-α组Hep-2细胞增殖抑制率及凋亡率较高,且20 pg/mL TNF-α组<50 pg/mL TNF-α组<100 pg/mL TNF-α组和200 pg/mL TNF-α组;与24 h比较,相同浓度TNF-α作用48 h后细胞增殖抑制率及凋亡率较高,差异有统计学意义(P<0.05);与对照组比较,各浓度TNF-α组Hep-2细胞S期细胞比例较低,G2/M期细胞比例较高;且在20~100 pg/mL浓度范围内,TNF-α浓度越高,G2/M期细胞阻滞越严重(P<0.05);与对照组比较,各浓度TNF-α组Hep-2细胞PCNA表达水平及CDK4活性较低;且20 pg/mL TNF-α组>50 pg/mL TNF-α组>100 pg/mL TNF-α组和200 pg/mL TNF-α组;与24 h比较,相同浓度TNF-α作用48 h后Hep-2细胞PCNA表达水平及CDK4活性较低,差异均有统计学意义(P<0.05)。结论 TNF对喉鳞状细胞癌Hep-2细胞增殖具有抑制作用,其能够使细胞阻滞于G2期,促进细胞凋亡,其作用可能与下调PCNA表达水平和CDK4活性有关。

TGF-β1在宫颈鳞状细胞癌及其细胞外基质中的表达及其与PCNA的关系

目的:检测TGF-β1、PCNA在宫颈癌组织中表达,探讨TGF-β1、PCNA在宫颈癌发生发展中的作用及其相互关系。方法:采用免疫组化方法检测宫颈癌组织中TGF-β1、PCNA的表达。结果:TGF-β1在宫颈癌中的表达高、低分化组,中、低分化组之间具有统计学意义;TGF-β1在细胞外基质中的表达在宫颈癌各临床分期之间具有统计学意义;PCNA在宫颈癌高、中、低分化组中具有统计学意义。结论:瘤细胞内TGFβ1的减少和细胞外基质中TGFβ1分泌的增多具有协同作用,与肿瘤恶性转化、生长、侵袭、浸润转移有关;PCNA的表达是细胞增殖活性的指标。瘤细胞自身分泌TGFβ1反作用肿瘤,可提高PCNA增殖活性,旁分泌TGFβ1为PCNA阳性肿瘤提供了侵袭转移的微环境。

结膜下注射丝裂霉素C的抗瘢痕化效果和安全性研究

目的 研究结膜下注射丝裂霉素C（mitomycin C,MMC）对兔眼瘢痕化模型的抗瘢痕化效果及对兔眼局部组织的毒副作用,探讨其作为青光眼滤过性手术后抗瘢痕形成辅助用药的可行性及有效性。方法 取18只健康成年新西兰大白兔,随机分为3组,分别为A组、B组和C组,每组12眼,建立实验性瘢痕化模型。A组术后3 d结膜下注射0.4 g·L-1的MMC 0.3 m L,B组术中巩膜瓣下放置浸泡0.4 g·L-1MMC的棉片5 min,C组术后3 d结膜下注射生理盐水（normal saline,NS）0.3 m L。应用结膜印迹细胞学检查观察结膜损伤情况。分别于术后7 d、14 d、28 d分批处死实验兔,摘出眼球,应用免疫组织化学染色检查观察成纤维细胞增殖细胞核抗原（proliferation cell nuclear antigen,PCNA）的表达情况,应用光镜观察手术部位的病理改变。结果术后3组均未出现结膜伤口渗漏,A组、B组角膜上皮点状缺损于术后1周消失,C组无角膜上皮点状缺损。结膜印迹细胞学检查显示A组和B组结膜印迹细胞分级均为2~3级,C组为2级。术后7 d、14 d、28 d光镜下,C组手术区球结膜下炎性细胞、纤维细胞、新生毛细血管增多,纤维组织增生较A组和B组显著。免疫组织化学染色结果显示,术后7 d,A组、B组、C组每高倍视野PCNA阳性细胞计数分别为（12.83±2.08）个、（14.37±3.76）个、（28.12±6.74）个;术后14 d,3组PCNA阳性细胞计数分别为（13.81±1.53）个、（16.28±3.78）个、（25.67±4.45）个;术后28 d,3组PCNA阳性细胞计数分别为（11.96±1.45）个、（13.07±2.04）个、（17.69±3.11）个;相应时间点,A组、B组PCNA阳性细胞计数均较C组少（均为P=0.000）,但A组与B组间差异均无统计学意义（均为P〉0.05）。结论 结膜下注射MMC能有效抑制手术后术区的瘢痕化,与术中常规应用MMC相比,其对结膜的损伤程度无明显差异,对其进一步研究有望为青光眼滤过手术后抗瘢痕化提供一种使用方便、安全、有效的局部用药方式。

萎胃康颗粒对慢性萎缩性胃炎大鼠胃黏膜上皮细胞PCNA和EGFR蛋白表达的影响

目的:探讨萎胃康颗粒对大鼠慢性萎缩性胃炎(CAG)的治疗作用及其机制。方法:90只SD大鼠随机取出18只为正常对照组,其余鼠造模后随机分为4组,模型组、萎胃康高、低剂量组、三九胃泰组均采用多重刺激复制大鼠CAG模型。在造模成功后分别ig萎胃康6,3 g.kg-1,三九胃泰1.6 g.kg-1,0.9%的生理盐水20 mL.kg-1。用药30 d后HE染色、透射电镜观察大鼠胃黏膜萎缩情况,免疫组化法观察胃黏膜上皮细胞中增殖细胞核抗原(PCNA)和表皮生长因子受体(EGFR)的表达。结果:光镜和电镜下均显示,萎胃康高、低剂量组胃黏膜病理变化比模型组明显减轻。模型组PCNA标记指数44.96%和EGFR的平均吸光度(A)0.183±0.030,明显高于正常组PCNA标记指数29.30%和EGFR的A 0.125±0.039。萎胃康高、低剂量组PCNA标记指数分别为29.58%,29.97%,EGFR的A分别为0.100±0.023,0.104±0.027,与模型组比较,表达降低(P<0.05或P<0.01)。结论:中药萎胃康颗粒对慢性萎缩性胃炎大鼠胃黏膜有明显修复作用,其作用机制可能是通过抑制胃黏膜PCNA和EGFR的过度表达而抑制细胞增殖和恶性转化实现的。

氟他胺对胚胎期尿道下裂大鼠PCNA、AR表达的影响

目的观察氟他胺(Flu)对胚胎期SD大鼠尿道及睾丸间质细胞增殖细胞核抗原(PCNA)、雄激素受体(AR)表达水平的影响,探讨其引起尿道下裂机制。方法将孕鼠于第12～17天连续皮下注射Flu(6.0546 mg/kg.d)染毒造模,在第20天行破宫产取子代雄鼠的尿道生殖结节和睾丸,用免疫组化检测大鼠尿道生殖结节、间充质细胞、尿道细胞及睾丸间质细胞PCNA、AR表达变化,RT-PCR技术检测睾丸间质细胞PCNA、AR mRNA表达变化。结果免疫组化显示PCNA在Flu染毒组大鼠生殖结节、间充质细胞、尿道细胞及睾丸间质细胞中蛋白表达明显低于对照组(P<0.05),AR在Flu染毒组尿道细胞及睾丸间质细胞表达与对照组无差异(P>0.05);RT-PCR显示:PCNA mRNA在Flu染毒组大鼠睾丸间质细胞中蛋白表达明显低于对照组(P<0.05),AR mRNA在Flu染毒组睾丸间质细胞表达与对照组无差异(P>0.05)。结论 Flu引起尿道下裂不是通过改变AR水平实现,可能是通过降低睾酮激素水平或与雄激素竞争性结合AR而导致尿道下裂的发生。

Multiple biomarkers of colorectal tumor in a differential diagnosis model:A quantitative study

AIM:To evaluate the multiple biomarkers of colorectal tumor and their potential usage in early diagnosis of colorectal cancers. METHODS:Multiple biomarkers (DNA contents,AgNOR, PCNA,p53,c-erbB-2) in 10 normal colorectal mucosae,37 colorectal adenomas and 55 colorectal cancers were analyzed quantitatively in the computed processing imaging system. Discrimination patterns were employed to evaluate the significance of single and multiple indices in diagnosis of colorectal cancers. RESULTS:The mean values of the analyzed parameters increased in order of the normal mucosa,adenoma and adenocarcinoma,and this tendency reflected the progression of colorectal malignancy.The parameters including DNA index,positive rates,densities of AgNOR,c-erbB-2,and p53, shape and density of nucleus were relatively valuable for diagnoses.Then a diagnostic discrimination model was established.The samples were confirmed with the model, the sensitivity rates in cancer group and adenoma group were 96.36% and 89.19%,respectively.The value of proliferating cell nuclear antigen (PCNA) in early diagnosis of colorectal cancers was uncertain. CONCLUSION:The quantitative evaluation of some parameters for colorectal tumor can provide reproducible data for differential diagnosis.The established diagnostic discrimination model may be of clinicopathological value, and can make the early diagnosis of colorectal cancer possible.

红藤提取物联合5-氟尿嘧啶抑制肝癌细胞生长作用及机制研究

目的研究红藤提取物联合5-氟尿嘧啶对人肝癌HepG2细胞生长的抑制作用,并初步探讨其作用机制。方法体外培养HepG2细胞,以不同质量浓度的红藤提取物作用于细胞,采用MTT法检测其对细胞生长的影响,选择后续实验浓度。将HepG2细胞分为对照组、红藤提取物(40 mg/L)组、5-氟尿嘧啶(10μmol/L)组及联合用药(红藤提取物40 mg/L+5-氟尿嘧啶10μmol/L)组,采用MTT法检测细胞增殖抑制率,流式细胞仪检测细胞周期,Western blotting法检测细胞中增殖细胞核抗原(PCNA)、细胞周期蛋白D1(Cyclin D1)及细胞周期依赖性蛋白激酶4(CDK4)表达水平。结果 MTT检测结果显示,红藤提取物呈质量浓度依赖性地抑制HepG2细胞增殖,选择其质量浓度为40mg/L用于后续实验。与对照组比较,红藤提取物组和5-氟尿嘧啶组细胞增殖抑制率显著升高,G_0/G_1期细胞比例显著升高,S期和G2/M期细胞比例显著降低,细胞中PCNA、Cyclin D1、CDK4蛋白的表达显著降低(P<0.05)。与5-氟尿嘧啶组比较,联合用药能显著抑制HepG2细胞增殖,阻滞细胞周期,抑制细胞中PCNA、Cyclin D1、CDK4蛋白表达(P<0.05)。结论红藤提取物联合5-氟尿嘧啶能够增强对HepG2细胞生长的抑制作用,其作用机制可能与抑制细胞中PCNA、Cyclin D1、CDK4蛋白表达水平有关。

Inhibitory effect of a new gossypol derivative apogossypolone (ApoG2) on xenograft of human prostate cancer cell line PC-3

Objective: To investigate the inhibitory effect of apogossypolone (ApoG2) on prostate cancer cell line PC-3 in vivo, and explore its mechanism. Methods: The models of transplantation tumors in Balb/c nu/nu mice were established via subcutaneous injection of PC-3 cells and the tumor-transplanted mice were divided into 4 groups: control group and three ApoG2 treatment groups, with 10 mice in each group. Volumes of the tumor were estimated every 2 d and the morphology of tumor tissues was observed. Immunohistochemistry was employed to observe the expression of Bcl-2, PCNA, CD31, caspase-3 and caspase-8 in tumor tissues. Results: ApoG2 (2.5 mg/kg-10 mg/kg) given intraperitoneally once a day can obviously inhibit the growth of subcutaneous prostatic carcinoma implant. The tumor volume decreased obviously when the treatment dosage was bigger than 5.0 mg/kg (P<0.01). Meanwhile, ApoG2 decreased the expression of PCNA and CD31, and enhanced the expression of caspases-3, caspase-8 in tumor tissues. Conclusion: ApoG2 exert an inhibitory effect on prostatic carcinoma possibly by inducing apoptosis and inhibiting tumor angiogenesis.

Components of the mitogen-activated protein kinase cascade are activated in hepatic cells by Echinococcus multilocularis metacestode

AIM： To explore the effect of Echinococcusmultilocularis on the activation of mitogen-activated protein kinase （MAPK） signaling pathways and on livercell proliferation.METHODS： Changes in the phosphorylation of MAPKs and proliferating cell nuclear antigen （PCNA）expression were measured in the liver of patients withalveolar echinococcosis （AE）. MAPKs, MEK1/2 [MAPK/extracellular signal-regulated protein kinase （ERK）kinase] and ribosomal S6 kinase （RSK） phosphorylationwere detected in primary cultures of rat hepatocytesin contact in vitro with （1） E. multilocu/aris vesicle fluid（EmF）, （2）E. multilocularis-conditioned medium （EmCM）.RESULTS： In the liver of AE patients, ERK 1/2 andp38 MAPK were activated and PCNA expression wasincreased, especially in the vicinity of the metacestode.Upon exposure to EmF, p38, c-Jun N-terminal kinase（JNK） and ERK1/2 were also activated in hepatocytesin vitro, as well as MEK1/2 and RSK, in the absenceof any toxic effect. Upon exposure to EmCM, only JNKwas up-regulated.CONCLUSION： Previous studies have demonstratedan influence of the host on the MAPK cascade inE. multilocularis. Our data suggest that the reverse,i.e. parasite-derived signals efficiently acting onMAPK signaling pathways in host liver ceils, is actuallyoperating.

LOW-DOSE RADIOACTIVE ENDOVASCULAR STENTS PREVENT NEOINTIMAL HYPERPLASIA IN RABBITS RESTENOSIS MODEL

Objective To evaluate the effects of low-dose radioactive stents on the prevention of restenosis in rabbit model. Methods The stents were bombarded with suitable charged particles of adapted energy in the cyclotron to create a proper mixture of the radionuclides 59 Fe, 60 Co, 58 Co, 51 Cr, and 54 Mn. The radioactive stents were implanted in the iliac arteries of rabbits. The effects of radioactive stents on prevention of restenosis were assessed by angiography, histomorphometry and immunocytochemistry. Results All the iliac arteries that had been implanted with radioactive stents were patent on angiography and had no radiation complication during the 1～2 months of follow-up. There was a significant reduction in neointimal area (0.37±0.14mm 2 vs. 0.81±0.10mm 2, P<0.01), percent area stenosis (6.7±2.9% vs. 13.2±1.4%, P<0.01) and PCNA immunoreactive rate (2.00±1.58% vs. 10.88±6.98%, P<0.05) in the radioactive stent group compared with the control stent group. Conclusion Radioactive stents with an active of 0.91～1.65 μCi could inhibit SMC proliferation and neointimal hyperplasia in animal restenosis model. The low-dose radioactive stents are safe and feasible for prevention of restenosis.

Proliferation in rat gastric mucosal cells induced by chronic ethanol feeding through the ROS/BMK1 pathway

Objective: To investigate the correlation between the gastric mucosal cell proliferation and low-concentration alcohol intake in a chronic drinking rat model, and to investigate the possible role of ROS/BMK1 pathway in this process. Methods: SD rats were randomly divided into 4 groups: control group, administered with tap water; ethanol group, with 6% ethanol in the drinking water; quercetin group, with quercetin (100 mg/kg) by intragastric gavage twice a day; ethanol+quercetin group, administered with quercetin combined with 6% ethanol. The cell proliferation in rat gastric mucosa was analyzed by flow cytometery and proliferating cell nuclear antigen (PCNA) immunohistochemical staining. Activation of ERKs and BMK1 was evaluated by the expression and phosphorylation of these kinases using Western Blot analysis. Results: Compared to the controls, the cell proliferation in gastric mucosa of rats exposed to the ethanol for 7 d was enhanced, and the activation of BMK1 was also increased in this period. Otherwise quercetin, as a free radical scavenger, attenuated increased cell proliferation and activation of BMK1 in rat stomach treated with ethanol. However, no changes of ERKs expression and phosphorylation occurred in the rats in all groups. Conclusion: These results suggested that the ROS and BMK1 activation may be a central mechanism, which underlies cell proliferation in rat gastric mucosa stimulus with the chronic low-concentration ethanol.

Curcumin down-regulates PCNA,cyclin D1 and Bcl-X_L expression in human keratinocyte cell lines

Objective：To evaluate the effects of curcumin on regulating the proliferation,cell cycle distribution,apoptosis and relevant mechanisms in keratinocyte cell lines.Methods：The human immortalized human keratinocyte lines（HaCaT cells） were treated with different doses of curcumin.The effects of curcumin on cell viability were measured by MTT assay,and the cell cycle distribution and apoptosis determined by flow cytometry.The mRNA expression changes of proliferating cell nuclear antigen（PCNA）,cyclin D1 and Bcl-xL were from real-time PCR analysis and the protein levels were detected by Western blotting.Results：Data obtained in the study showed that curcumin could cause significantly inhibitory effect on proliferation in HaCaT cells in a time- and dose-dependent manner.Cell arrest at G1/S phase and significant apoptosis were observed after being treated with curcumin for 24 h.In association with these,the expression of PCNA,cyclin D1 and Bcl-xL were decreased both at mRNA and protein levels for the same treatment.Conclusion：Curcumin can inhibit proliferation,induce cell arrest at G1/S phase and cause apoptosis in HaCaT cells.The decreased expression of PCNA,cyclin D1 and Bcl-xL induced by curcumin contributes to the above effects in vitro.

Expression of Smac and the relationship with cell apoptosis and proliferation in hepatocarcinoma tissues

Objective:The aim of the study was to investigate the expression of Smac protein in human hepatocarcinoma and their relationship with cell apoptosis and proliferation.Methods:The expressions of Smac and the proliferating cell nuclear antigen (PCNA) in 41 cancer tissues,41 adjacent cirrhosis tissues and 9 normal control tissues in hemangioma were assessed by two-step immunohistochemical method and apoptosis was detected by TUNEL method.Results:Smac protein was expressed in 14 (34.14%) of the 41 cases of hepatocarcinoma,in 23 (56.10%) of the 41 cases of the adjacent cirrhosis tissues,and in 7 (77.8%) of the normal tissues in hemangioma.Smac protein positive expression rate in hepatocarcinoma was significantly lower than that in the adjacent cirrhosis tissues and the normal control tissues,χ2 were 3.989 and 4.115,respectively,and P were 0.046 and 0.042,respectively.Smac protein expression in cancer was significantly correlated with the ratio of apoptotic index to proliferative index,t'=2.260,P<0.05,but was not with the clinicopathological indicators such as the age and the histological grade,P>0.05.Conclusion:The relatively lower level of the expression of Smac may in a certain extent break the dynamic balance between apoptosis and proliferation of hepatocarcinoma cells,and then plays an important role in the pathogenesis of hepatocarcinoma.

The significance and features of apoptosis and proliferation of NK/T cell lymphoma

Objective:The aim was to study the features and clinical significance of cell apoptosis and proliferation of NK/T cell lymphoma.Methods:TdT-mediated dUTP nick end labeling and immunohistochemical Streptavidin-peroxidase method were used to study cell apoptosis and the expression of proliferation cell nuclear antigen in 25 NK/T cell lymphoma and 10 reactive lymphoid tissues.Results:Apoptotic index(AI) and proliferative index(PI) averaged(1.92%±0.86%) and(41.48%±5.10%) respectively in the 25 NK/T cell lymphomas and(6.70%±1.89%) and(20.10%±2.77%) in the 10 reactive lymphoid tissues.Compared with reactive lymphoid tissues,AI was significantly reduced in NK/T cell lymphoma(t=10.80,P<0.01) while PI significantly increased(t=12.39,P<0.01).In addition,in NK/T cell lymphoma,AI and PI were positively related(r=0.69,P<0.01).Conclusion:In NK/T cell lymphoma,cell apoptosis is reduced while cell proliferation increased.The imbalance between cell apoptosis and cell proliferation is closely related to the development and progression of NK/T cell lymphoma.

Relationship Between Apoptosis and PCNA Expression of Keratinocytes in Condylomata Acuminata

Objecrive: To investigate the relationship between apoptosis and proliferating cell nuclear antigcn (PCNA)expression of keratinocytes in Condylomata acuminata (CA). Methods: PCNA expression was observed byimmunohistochemistry technique (ABC method) in 51 CAspecimens and 1 normal specimens of foreskin or vaginalmucosae. 55 specimens (40 in the CA group and 15 in thecontrol group) were randomly sampled for in situ labelingof apoptotic cells using the TUNEL method. Results: Positive expression of PCNA in CA and controlgroups were 90.2% and 77.8%, respectively, and theproliferation index in CA group was significantly higherthan that in the control group (P<0.001). The positive rateof apoptosis was 42.5% in the LA group and 53.3% in thecontrol group, and there were no significant differences inthe apoptotic index and apoptosis-proliferation ratiobetween two groups (P>0.05). The proliferation indexshowed a significant negativc correlation with theapoptosis-proliferation ratio (r=-0.62, P=0.01) in the CAgrp. Conclusion: It is suggested that the proliferativeappearance of CA could be due to the imbalance betweencell growth and cell death which is caused by moreproliferation and less apoptosis in keratinocytes.

Expression of CD44V6 and PCNA in squamous cell carcinomas

OBJECTIVE: To investigate the expression of cluster of differentiation 44 variant 6 (CD(44V6)) and proliferating cell nuclear antigen (PCNA) in ocular squamous cell carcinomas. METHODS: Streptavidin-biotin complex (SABC) immunohistochemistry was used to explore the expression of CD(44V6) and PCNA in 35 cases of ocular squamous cell carcinomas, 20 cases of papillomas, and 11 cases of normal eyelid tissue. RESULTS: The CD(44V6) positive rate was 62.9% (22/35) in ocular squamous cell carcinomas, 15.0% (3/20) in papillomas, but not detectable in the 11 cases of normal eyelid tissue. The positive expression rates of CD(44V6) in ocular squamous cell carcinomas were significantly higher than in benign tumors (chi(2) = 11.57, P

Interferon-γ inhibits in situ expression of PDGF-β mRNA by smooth muscle cells in injured rabbit arteries after transluminal balloon angioplasty

Objective To elucidate the mechanism of interferon-gamma (IFN-γ) to inhibit the restenosis after successful percutaneous transluminal angioplasty (PTA).Methods A rabbit vascular restenotic model was constructed and the proliferation of intimal smooth muscle cells (SMCs) were observed by monitoring their expression of proliferating cell nuclear antigen (PCNA) and platelet-derived growth factor β chain mRNA (PDGF-β mRNA) at the indicated time points. Results IFN-γ could significantly inhibit the expression of PCNA by intimal SMCs one week after denudation, when counting 200 intimal cells for PCNA-positive reactions with an inhibitory rate of 88.50% (P<0.001). IFN-γ could downregulate in situ expression of PDGF-β mRNA by these cells as we calculated the average number of PDGF-β mRNA positive cells per square millimetre area at ×400 magnification with reduced rates of 86.85% in 1 week group (P<0.001), of 93.66% in 2 week group (P<0.001) and of 52.92% in 4 week group (0.02<P<0.05), respectively. Conclusions The local production of PDGF-β by vascular intimal SMCs via an autocrine mechanism may be responsible for continuous proliferation of these cells and the formation of neointima after injury. This could be inhibited by IFN-γ through downregulating the expression of PDGF-β mRNA. These results provide an in vivo basis for IFN-γ to be used clinically for the management of restenosis after percutaneous transluminal angioplasty.

Ginsenosides stimulated the proliferation of mouse spermatogonia involving activation of protein kinase C

The effect of ginsenosides on proliferation of type A spermatogonia was investigated in 7-day-old mice. Spermatogonia were characterized by c-kit expression and cell proliferation was assessed by immunocytochemical demonstration of proliferating cell nuclear antigen (PCNA). After 72-h culture, Sertoli cells formed a confluent monolayer to which numerous spermatogonial colonies attached. Spermatogonia were positive for c-kit staining and showed high proliferating activity by PCNA expression. Ginsenosides (1.0～10 μg/ml) significantly stimulated proliferation of spermatogonia. Activation of protein kinase C (PKC) elicited proliferation of spermatogonia at 10-8 to 10-7 mol/L and the PKC inhibitor H7 inhibited this effect. Likewise, ginsenosides-stimulated spermatogonial proliferation was suppressed by combined treatment of H7. These results indicate that the proliferating effect of ginsenosides on mouse type A spermatogonia might be mediated by a mechanism involving the PKC signal transduction pathway.