Proliferating cell nuclear antigen of Ulva prolifera is involved in the response to temperature stress

Ulva prolifera is the most common specie causative to green tide,and its growth is sensitive to temperature stress.However,the mechanisms of U.prolifera response to temperature stress remain elusive.In this study,high temperature(36℃)stimulus promoted the death of unformed cell wall protoplasts and delayed the division of formed cell wall protoplasts,while low-temperature(4℃)stimulus did not,suggesting that the mechanisms of the response of U.prolifera to high and low temperature stresses are different.Transcriptome results show that proliferation-related genes were differentially expressed under high and low-temperature stresses,especially the proliferating cell nuclear antigen(PCNA)and cyclins(CYCs).Subsequently,the interaction between PCNA and Cyclin A was confirmed by Co-immunoprecipitation,yeast two-hybrid,and so on.Furthermore,high-and low temperature stresses induced the expression of PCNA and Cyclin A in varying of degrees,and activated extracellular signal-regulated kinase(ERK)signal pathway.These results suggest,PCNA,Cyclin A,and ERK signal pathway played important roles in the resistance of U.prolifera to temperature stress.Interestingly,high-temperature stress induced an increase of miR-2916 in abundance,and exhibiting reverse expression of PCNA;and PCNA was target gene of miR-2916,suggesting that miR-2916 protected U.prolifera from high-temperature stress via post-transcriptionally regulation of PCNA.This study laid a foundation for understanding the function of PCNA and Cyclin A,moreover,it has a guiding significance to explore the mechanisms of the response to temperature stress from proliferation-related genes regulatory networks in U.prolifera.

Comparative Analysis of Ki-67 Protein as a Proliferative Expression Index in Cutaneous Basal and Squamous Cell Carcinoma in Federal Medical Centre Umuahia, Nigeria

Background: Evaluating the tumor proliferative index helps predict clinical behavior and provides prognostic insights for cutaneous basal cell carcinoma (cBCC) and squamous cell carcinoma (cSCC). Objective: This study aimed to identify differences in the proliferative indices among variants of cBCC and cSCC diagnosed at a tertiary healthcare center. Method: Skin biopsies histologically diagnosed as cBCC and cSCC between 2012 and 2018 at the Federal Medical Centre (FMC) Umuahia, Abia State, Nigeria, were analyzed. Archival formalin-fixed, paraffin-embedded (FFPE) tissue blocks were retrieved along with clinical data, and were prepared on charged microscope slides and the immunohistochemical staining was carried out. The primary antibody used in this study was clone BioCare CRM325C (RM) and adenotonsillar tissue blocks/slides served as positive controls. Ki-67 immunohistochemistry was performed on fresh 4µm sections of the tumor specimens. Results: The application of Ki-67 immunoperoxidase on both BCC and SCC cohort, yielded an intense observable brownish nuclear stain in areas of dense proliferating tumour cells on both cutaneous tumours. The average Ki-67 index for all cSCC cases was 24.7%, with a range of 2.3% - 80%, while the mean for cBCC was 15.8%, ranging from 1.2% - 45.6%. Variants with high proliferative indices were observed in 11.9% of cBCC cases and 29.1% of cSCC cases. Among the low proliferative index category, cSCC accounted for 5.4%, while cBCC represented 14.3%. For mild proliferative indices, cSCC cases made up 7.3% and cBCC, 11.9%. The majority of cases showed moderate proliferative indices, with 61.9% for cBCC and 58.2% for cSCC. Overall, there was a significant difference in proliferative indices between cSCC, cBCC, and their variants. Conclusion: The study found a significantly higher rate of cell proliferation, measured by Ki-67 immunostaining, in cSCC and its variants compared to cBCC. However, certain variants of cBCC also exhibited high Ki-67 expression, indicating they can be as aggressive as some cSCC variants.

Influence of norcantharidin on proliferation,proliferation-related gene proteins prolifera-ting cell nuclear antigen and Ki-67 of human gallbladder carcinoma GBC-SD cells

BACKGROUND: Gallbladder carcinoma is a highly lethal and aggressive disease with early metastasis, strong invasion and poor prognosis. Most patients with this disease are at the advanced and un-resectable stage and should be consi- dered for palliative treatment such as chemotherapy and ra- diotherapy. Unfortunately, reports of chemotherapy and radiotherapy for gallbladder carcinoma are disappointing. We investigated the influence of norcantharidin (NCTD) on proliferation, proliferation-related gene proteins PCNA and Ki-67 of human gallbladder carcinoma GBC-SD cells in vitro. METHODS: GBC-SD cell lines of human gallbladder carci- noma were cultured by the cell culture technique. The ex- periment was divided into NCTD group and control group. The tetrazolium-based colorimetric assay was used to evaluate cell growth. The streptavidin-biotin complex method was used to determine the expressions of prolifera- tion-related gene proteins PCNA and Ki-67 of human gall- bladder carcinoma GBC-SD cells. RESULTS: NCTD inhibited the growth and proliferation of GBC-SD cells from 10 mg/L or after 6 hours in a dose- and time-dependent manner, with the IC50 value of 56.18 μg/ ml at 48 hours. After treatment with NCTD, the expression of PCNA (0.932 ±0.031 vs. 0.318 ±0.023, P<0.001) and Ki-67 (0.964 ±0.092 vs. 0.297 ±0.018, P<0.001) proteins were decreased significantly. CONCLUSION: NCTD inhibits the proliferation of human gallbladder carcinoma GBC-SD cells in vitro and the expres- sion of their proliferation-related gene proteins PCNA and Ki-67.

The Relationship of Expression of bcl-2, p53, and Proliferating Cell Nuclear Antigen (PCNA) to Cell Proliferation and Apoptosis in Renal Cell Carcinoma

To investigate the relationship of bcl-2, p53, proliferating cell nuclear antigen (PCNA) to cell proliferation, apoptosis and pathological parameters, the patterns of cell growth and turnover in renal cell carcinoma (RCC), formalin-fixed and paraffin-embedded tissue blocks from 34 patients with RCC were examined. Cell proliferation activity was detected by PCNA immunostaining and the proliferation index (PI) was expressed as a percentage of the PCNA-positive cells in the tumor cells. Apoptosis was detected by terminal deoxy- nucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL), and the apoptotic index (AI) was expressed as a percentage of the TUNEL-positive cells in the tumor cells. Expressions of bcl-2 and p53 were assessed immunohistochemically. Our results showed that the PI ranged from 6.0 % to 24.0 % (median 12.3 %) and the AI from 2.0 % to 8.0 % (median 5.4 %) in RCC. The expression of the bcl-2 protein was demonstrated in 15 cases (44.1 %); the expression of the p53 protein, however, was seen in only 3 case. bcl-2 positivity was not associated with PI or AI or any pathological parameters. There were close associations between PI and tumor grade and stage, and a significant relationship between AI and the tumor grade of RCC. Our study suggests that bcl-2 positivity was not associated with PI or AI or any pathological parameters. There are close associations between PI and AI and tumor grade and stage of RCC. Active cell proliferation may be accompanied by frequent apoptosis in RCC.

Evaluation of proliferation kinetics in large intestinal neoplasms:Comparative study on the expression of proliferating cell nuclear antigen and AgNOR counting

Expression of proliferating cell nuclear antigen (PCNA) in human colorectal lesions was studied immunohistologically and compared with the results of silver stained nucleolar organized regions (AgNOR)counting for evaluating the changes of proliferative kinetics in adenoma-carcinoma sequence of the large intestine.Ninety-six formalin-fixed paraffin-embedded specimens were used, which consisted of 21 normal colon mucosa,23 adenocarcinomas and 52 adenomas (34 cases with mild atypia, 12 morderate and 6 severe). Three types of PCNA distribution pattern were identified. 73. 9% normal mucosa was type A pattern. Type C pattern was characteristic of adenocarcinoma, and adenoma was of type B or C pattern. Labeling index (LI) of PCNA was an important parameter to evaluate the proliferation activity. In normal mucosa, LI of PCNA was 0. 34±0. 10, while in malignant lesions, it was 0. 71±0. 09. Furthermore, the LI had a tendency to elevate with the degree of atypia in adenoma from 0. 52±0. 10 in mild atypia to 0. 68±0. 07 in severe atypia. The pattern of AgNOR counting changes, which were 1. 97±0. 36 and 4. 16±1. 24 in the normal mucosa and malignant mucosa respectively, was found to be similar to Ll changes of the PCNA in different lesions of the same section. A good correlation was found between the mean number of AgNOR per nucleus and the LI of PCNA in 23 adenocarcinomas (r=0. 59, P <0. 05). These results suggested that proliferation kinetics could be comprehensively evaluated by combining immunohistological staining for PCNA and a simple silver staining for NOR, which would be advantageous for the diagnosis of colorectal lesions and for evaluating the degree of histopathological atypia of adenomas.

Effects of Peptide Nucleic Acids against Ki-67 Gene on the Proliferation and Apoptosis of Human Renal Carcinoma Cell Line

To investigate the effects of anti-sense peptide nucleic acids （PNAs） targeting Ki-67 gene on modulation of the proliferation and apoptosis of human renal carcinoma cell lines, human renal carcinoma cell line 786-0 cells were treated with anti-sense PNAs at different concentrations （1.0 μmol/L, 2.0 μmol/L, 10.0 μmol/L）. The Ki-67 expression of 786-0 cells was detected by immunohistochemical technique and Western blot method respectively. The proliferation of 786-0 cells was studied by cell growth curves and ^3H-thymidine incorporation. The apoptosis of 786-0 cells was detected by TUNEL assay. The control groups were treated with anti-sense oligonucleotide （ASODNs） targeting Ki-67 gene. Our results showed that the Ki-67 expression of 786-0 cells treated with anti-sense PNAs （16.9±0.7） was significantly inhibited as compared with that of the control groups （28.6±0.4） （P〈0.01）. The Ki-67 protein rate of 786-0 cells treated with anti-sense PNAs （42.1 ±2.2） was significantly reduced when compared with that of the control groups （83.6± 1.4） （P〈0.01）. Proliferation of 786-0 cells treated with anti-sense PNAs （20.7 ± 1.5） was significantly inhibited as compared with that of the control groups （58.6± 1.4） （P〈0.01）. The apoptosis rate of 786-0 cells treated with anti-sense PNAs （28.7 ± 2.3） was significantly increased higher compared with that of the control groups （13.8 ±1.0） （P〈0.01）. From these finds we are led to conclude that anti-sense PNAs targeting Ki-67 gene have stronger effects on the inhibition of the proliferation and induction of apoptosis of human renal carcinoma cells than ASODNs targeting Ki-67 gene. The strategies using anti-sense PNAs targeting Ki-67 gene may be a promising approach for the treatment of renal cell carcinoma.

P53、P16及Ki-67与早期食管癌患者ESD术后复发的关系分析

目的 分析研究抑制蛋白基因P53(P53)、抑制蛋白基因P16(P16)及细胞增殖核抗原Ki-67(Ki-67)与早期食管癌患者内镜黏膜下剥离术(ESD)术后复发的关系。方法 选取2019年1月至2023年1月三门峡市中心医院收治80例的早期食管癌患者作为研究对象,均进行ESD治疗。比较所有患者癌组织与癌旁组织(距肿瘤边缘>3 cm,镜下未见肿瘤组织或不典型增生组织)P53、P16、Ki-67蛋白表达。ESD术后对患者随访1年,根据有无术后复发食管癌,将患者分为复发组(n=20)与无复发组(n=60)。比较两组癌组织P53、P16、Ki-67蛋白表达。采用多因素Logistic回归分析早期食管癌患者ESD术后复发的影响因素,并绘制ROC曲线分析P53、P16、Ki-67蛋白表达与早期食管癌患者ESD术后复发。结果 与癌旁组织相比,癌组织P53、Ki-67蛋白表达升高,P16蛋白表达降低(t=9.276、13.987、10.595,均P<0.05);复发组的癌组织P53、Ki-67蛋白表达均高于无复发组,P16蛋白表达低于无复发组(t=5.086、4.648、5.139,均P<0.05);多因素Logistic回归分析显示,肿瘤低分化(OR=1.870)、肿瘤浸润侵犯黏膜下层(OR=1.808)、有淋巴结转移(OR=2.089)、P53蛋白高表达(OR=2.046)、P16蛋白低表达(OR=1.988)及Ki-67蛋白高表达(OR=1.761)均是早期食管癌患者ESD术后复发的独立危险因素(P<0.05);ROC曲线分析显示,P53、P16、Ki-67蛋白表达及联合检测的曲线下面积(AUC)分别为0.803、0.828、0.834、0.942,联合检测优于单一检测(P<0.05)。结论 P53、P16及Ki-67蛋白与早期食管癌患者ESD术后复发情况相关,可以作为辅助预测的相关诊断指标。

Neuron specific enolase,p53蛋白和proliferating-cell nuclear antigen在肺癌组织中的表达及意义

目的：研究神经元特异性烯醇化酶（neuronspecificenolase，NSE）的表达，与p53蛋白和增殖细胞核抗原（prolif－erating－cellnuclearantigen，PCNA）表达的关系及意义．方法：用特异性鼠抗人单克隆抗体，按LSAB免疫组织化学方法检测石蜡包埋的肺癌标本中NSE，p53蛋白和PCNA的表达．结果：在小细胞性肺癌（SmallCellLungCancer，SCLC）中，NSE阳性表达者，PCNA标记指数（LabellingIndex，LI）高于NSE阴性者，而p53蛋白的表达与NSE的表达无关．在非小细胞性肺癌（non－smallcelllungcancr，non－SCLC）中，p53蛋白的表达和PCNALI均与NSE的表达无关．结论：在SCLC的发生及发展过程中，神经内分泌功能可能起了部分作用．而p53抑癌基因在SCLC的发生中并不起着重要的作用．

Evaluation of germ-cell kinetics in infertile patients with proliferating cell nuclear antigen proliferating index

Aim: To explore the usefulness of proliferating cell nuclear antigen proliferating index (PCNA PI) in the pathologicaldiagnosis and treatment of male infertility. Methods: Testicular biopsy specimen obtained from 48 cases of male in-fertility and 2 normal controls were fixed and embedded. The sections were stained with anti-PCNA monoclonal anti-bodies or haematoxylin/eosin. Proliferating index (PI), expressed as the percentage of germ-cell nuclei positivelystained with PCNA antibody, was assessed from more than 20 seminiferous tubules or 600 germ-cells. Results: Theinfertile patients were divided into 4 groups: Group 1, normal spermatogenesis (14 cases); Group 2, hypospermato-genesis (16 cases); Group 3, germinal arrest (10 cases); Group 4, Sertoli cell only syndrome (8 cases). The PCNAPI of normal control testis was 86.5 % (mean value). Group 3 had a significantly lower PCNA PI (29.8 %) than nor-mal testis; Group 1 and 2 had similar Pis (82.3% and 82.3%, respectively) as the control testis. PI of the negativecontrol (Group 4) was 0 as no germ-cells were found. Conclusion: PCNA PI is useful for assessing germ-cell ki-netics, especially for pathological diagnosis of germinal arrest which is difficult to differentiate by routine HE stainingtechnique. In germinal arrest, there is a significantly lowered PCNA PI, which is an indication of DNA synthesis dete-rioration, suggesting the use of therapies be different from those for hypospermatogenesis. (Asian J Androl 2001 Mar;3: 63-66)

Clinical significance of expression of proliferating cell nuclear antigen and E-cadherin in gastric carcinoma

AIM to investigate the expression of proliferating cell nuclear antigen(p CNA)and E-cadherin in gastric carcinoma and to analyze their clinical significance.METHODS A total of 146 patients were selected for this study,including 38 patients with intestinal metaplasia,42with dysplasia,and 66 with primary gastric cancer.In addition,40 patients with normal gastric tissues were selected as controls.the expression of p CNA and E-cadherin was detected by immunohistochemistry.Differences in p CNA and the E-cadherin labeling indexes among normal gastric mucosa,intestinal metaplasia,dysplasia,and gastric carcinoma were compared.Subjects with normal gastric tissues were assigned to a normal group,while gastric cancer patients were assigned to a gastric cancer group.the difference in p CNA and E-cadherin expression between these two groups was compared.the relationship between expression of p CNA and E-cadherin and clinicopathological features was also explored in gastric cancer patients.furthermore,prognosis-related factors,as well as the expression of p CNA and E-cadherin,were analyzed in patients with gastric cancer to determine the 3-year survival of these patients.RESULTS the difference in p CNA and the E-cadherin labeling indexes among normal gastric mucosa,intestinal metaplasia,dysplasia,and gastric carcinoma was statistically significant(p<0.05).During the transition of normal gastric mucosa to gastric cancer,the p CNA labeling index gradually increased,while the E-cadherin labeling index gradually decreased(p<0.05).the p CNA labeling index was significantly higher and the E-cadherin labeling index was significantly lower in gastric cancer than in dysplasia(p<0.05).the expression of p CNA was significantly higher in the gastric cancer group than in the normal group,but E-cadherin was weaker(p<0.05).there was a negative correlation between the expression of p CNA and E-cadherin in gastric carcinoma(r=-0.741,p=0.000).p CNA expression differed significantly between gastric cancer patients with and without lymph node metastasis and between patients at different t stages.E-cadherin expression also differed significantly between gastric cancer patients with and without lymph node metastasis(p<0.05).High t stage and positive p CNA expression were risk factors for the prognosis of patients with gastric cancer(RR>1),while the positive expression of E-cadherin was a protective factor(RR<1).the sensitivity,specificity,and accuracy of p CNA positivity in predicting the 3-year survival of patients with gastric cancer were 93.33%,38.89%,and0.64,respectively;while these values for E-cadherin negativity were 80.0%,41.67%,and 0.59,respectively.When p CNA positivity and E-cadherin negativity were combined,the sensitivity,specificity,and accuracy were66.67%,66.67%,and 0.67,respectively.CONCLUSION Combined detection of p CNA and E-cadherin can improve the accuracy of assessing the prognosis of patients with gastric cancer.

Mast cell density and the context of clinicopathological parameters and expression of p185,estrogen receptor,and proliferating cell nuclear antigen in gastric carcinoma

AIM:To investigate the relationship between the mast cell density(MCD)and the context of clinicopathological parameters and expression of p185,estrogen receptor(ER), and proliferating cell nuclear antigen(PCNA)in gastric carcinoma. METHODS:Mast cell,p185,ER,and PCNA were detected using immunohistochemical S-P labeling method.Mast cell was counted in tissue of gastric carcinoma and regional lymph nodes respectively,and involved lymph nodes(ILN)were examined as usual. RESULTS:MCD was significantly related to both age and depth of penetration(x^2=4.688,P<0.05 for age and x^2=9.350, P<0.01 for depth of penetration)between MCD>21/0.03 mm^2 and MCD≤21/0.03 mm^2 in 100 patients;MCD in 1-6 ILN group patients was significantly higher than that in 7-15 ILN or>15 ILN group patients(u=6.881,8.055,P<0.01); There were significant differences intergroup in positive expression rate of p185,ER and PCNA between MCD>21/ 0.03 mm^2 and MCD≤21/0.03 mm^2 in 100 patients. CONCLUSION:Mast cell may have effect on inhibiting invasive growth of tumor,especially in the aged patients; The number of mast cells,in certain degree,may predicate the number of involved lymph nodes,which is valuable for assessment of prognosis;MCD was related to the expression of p185,ER,and PCNA in gastric carcinoma.It suggests that mast cell accumulation may inhibit the proliferation and the dissemination of the gastric carcinoma. INTRODUCTION Recently,many studies have reported on the association of mast cell with various tumorst.In several malignancies,mast cell has been found to correlate with growth,penetration and prognosis of tumor.Therefore,our study was undertaken to investigate the relationship between the mast cell density (MCD)and the context of clinicopathological parameters and expression of p 185,estrogen receptor(ER),and proliferating cell nuclear antigen(PCNA)in gastric carcinoma.

The Relationship between Apoptosis and the Expression of Proliferating Cell Nuclear Antigen and the Clinical Stages in Gastric Carcinoma

The relationship between the apoptosis and the expression of proliferating cell nuclear antigen (PCNA) and the clinical stages in gastric cancers was studied. By using terminal deoxynucleotidyl transferase mediated nick end labelling (TUNEL) technique and PCNA immunohistochemical staining, the apoptosis and the expression of PCNA in tissue of gastric carcinoma were assayed in situ, the index of apoptosis (AI), index of PCNA (PI) and the rate of AI/PI were calculated. AI and PI in gastric cancer tissues were (6.5±3.7) % and (49.8±15.9) % respectively, and the rate of AI/PI was 0.13±0.05, which were obviously different from those of normal gastric mucosa in paragastric cancer ( P <0.01). With the advanced TNM stages of gastric carcinoma, the AI was decreased, PI was increased and the rate of AI/PI decreased in gastric carcinoma. There was significant difference in them between the gastric cancer tissues and normal gastric mucosa in pericarcinoma in TNM stage Ⅱ to Ⅳ ( P <0.05). It was suggested that the decreased apoptotic cells and the increased proliferating cells were obviously related to the tumor genesis and tumor progression in gastric carcinoma. The AI, PI and the rate of AI/PI would become the prognostic factors in advanced gastric carcinoma.

RELATIONSHIP BETWEEN PROLIFERATING CELL NUCLEARANTIGEN EXPRESSION AND ITS MALIGNANCY POTENTIAL IN COLORECTAL CARCINOMA

Objective: To study the relationship between proliferating cell nuclear antigen expression and its malignancy potential in colorectal carcinoma. Methods: Paraffin sections of 86 patients with advanced colorectal carcinoma were assessed by immunohistochemical study, using a mouse monoclonal antibody (pc-10, DAKO Co. USA) to check proliferating cell nuclear antigen (PCNA). To compare PCNA with conventional clinicopathologic factor, including p53 overexpression, tissue carcinoembnyonic antigen immunoreactivity pattern and flow cytometric DNA ploidy for assessing tumor malignancy potential. In addition, recurrence and survival of patients with advanced colorectal carcinoma after curative resection were analyzed in accordance with degree of PCNA expression. Results: PCNA-labeling index (PCNA-LI) increased significantly as the tumor stage advanced (p=0.0001). Strong correlations were observed between PCNA-LI and various pathologic parameters, including histologic differentiation (P=0.0027), lymphatic invasion (P=0.0001), vascular invasion (P=0.0001), lymph node metastasis (P=0.0001), and liver metastasis (P=0.0036). Mean PCNA-LI was also significantly higher in tumor with DNA aneuploidy (P=0.0006) and negative (P=0.01). Linear relationships were demonstrated between PCNA-LI and clinical outcomes; Recurrence rate was significantly greater in the group with higher than the mean PCNA-LI, who underwent curative resection (P<0.01), and three-year survival rates for curative cases with higher than the mean PCNA-LI were significantly poorer than those with lower than mean PCNA-LI (P<0.005). Conclusion: There were correlations between PCNA-LI and various pathologic parameters, PCNA-LI increased significantly as the tumor stage advanced in colorectal carcinoma, the rates of recurrence and death got higher as PCNA-LI increased after curative resection for colorectal carcinoma.

Cloning and characterization of proliferating cell nuclear antigen gene of Alexandrium catenella (Dinoflagellate) with respect to cell growth

Harmful algal blooms （HABs） have been affecting negatively the shellfish and aquaculture industries around the world. Though a lot of efforts have been made to disclose the changes of environmental factors involved and their effects on the HABs events, the molecular mechanism of this process remains unclear. To address this problem, proliferating cell nuclear antigen gene （pcna） was isolated and characterized from Alexandrium catenella. It showed high homology to those of other dinoflagellates （89% and 91% homology to Pfiesteria piscicid and Pyrocystis lunula, respectively）, and also 42%–43% homology to those of plant and animals. The expression level of pcna revealed by quantitative real time PCR was the lowest at the late lagging cell growth phase, increased to the highest at the late exponential phase, and then decreased at the stationary phase. Though the cell growth rate was also changing, no positive correlation between pcna expression level and cell growth rate was displayed throughout the whole cell growth stages （r 2 =0.024 6）. However, the pcna expression level had the similar trend with the change of cell growth rate throughout the whole growing process, e.g., from increasing at the earlier cell growth stage to decreasing at the following stages, though slightly lagging to the latter.

EXPRESSION OF P53 PROTEIN AND PROLIFERATING CELL NUCLEAR ANTIGEN IN HUMAN GESTATION TROPHOBLASTIC DISEASE

To study the relationship between p53 protein, proliferating cell nuclear antigen (PCNA) expression and benign or malignant gestational trophoblastic disease (MGTD). Methods: The histotomic sections of 48 patients with gestational trophoblastic disease and 24 patients of normal chorionic villi were stained using immunohistochemistry. The monoclonal antibodies were used to determine p53 protein and PCNA. Results: The frequency of p53 and PCNA positive expression were significantly different among the chorionic villi of normal pregnancy, hydratidiform mole (HM) and MGTD. But neither p53 nor PCNA has any relation with the clinical staging or metastasis of MGTD. Conclusion: Both P53 and PCNA are valuable in diagnosis of human gestational trophoblastic disease.

Proliferating cell nuclear antigen clamp associated factor,a potential proto-oncogene with increased expression in malignant gastrointestinal tumors

Gastrointestinal(GI)cancers,including malignancies in the gastrointestinal tract and accessory organs of digestion,represent the leading cause of death worldwide due to the poor prognosis of most GI cancers.An investigation into the potential molecular targets of prediction,diagnosis,prognosis,and therapy in GI cancers is urgently required.Proliferating cell nuclear antigen(PCNA)clamp associated factor(PCLAF),which plays an essential role in cell proliferation,apoptosis,and cell cycle regulation by binding to PCNA,is a potential molecular target of GI cancers as it contributes to a series of malignant properties,including tumorigenesis,epithelial-mesenchymal transition,migration,and invasion.Furthermore,PCLAF is an underlying plasma prediction target in colorectal cancer and liver cancer.In addition to GI cancers,PCLAF is also involved in other types of cancers and autoimmune diseases.Several pivotal pathways,including the Rb/E2F pathway,NF-κB pathway,and p53-p21 cascade,are implicated in PCLAF-mediated diseases.PCLAF also contributes to some diseases through dysregulation of the p53 pathway,WNT signal pathway,MEK/ERK pathway,and PI3K/AKT/mTOR signal cascade.This review mainly describes in detail the role of PCLAF in physiological status and GI cancers.The signaling pathways involved in PCLAF are also summarized.Suppression of the interaction of PCLAF/PCNA or the expression of PCLAF might be potential biological therapeutic strategies for GI cancers.

Abnormal expressions of proliferating cell nuclear antigen and P27 protein in brain glioma

Both proliferating cell nuclear antigen and P27 protein are important factors to regulate cell cycle. While, the combination of them can provide exactly objective markers to evaluate prognosis of patients with brain glioma needs to be further studied based on pathological level. OBJECTIVE： To observe the expressions of proliferating cell nuclear antigen and P27 protein in both injured and normal brain glioma tissues and analyze the effect of them on onset and development of brain glioma. DESIGN： Case contrast observation. SETTING： Department of Neurosurgery, the Second Affiliated Hospital of Xi＇an Jiaotong University. PARTICIPANTS： A total of 63 patients with brain glioma were selected from Department of Neurosurgery, the Second Affiliated Hospital of Xi＇an Jiaotong University from July 1996 to June 2000. There were 38 males and 25 females and their ages ranged from 23 to 71 years. Based on pathological classification and grading standards of brain glioma, patients were divided into grade I - II （n=30） and grade III- IV （n = 33）. All cases received one operation but no radiotherapy and chemiotherapy before operation. Sample tissues were collected from tumor parenchyma. Non-neoplastic brain tissues were collected from another 12 non-tumor subjects who received craniocerebral trauma infra-decompression and regarded as the control group. There were l0 males and 2 females and their ages ranged from 16 to 54 years. The experiment had got confirmed consent from local ethic committee and the collection was provided confirmed consent from patients and their relatives. All samples were restained with HE staining so as to diagnose as the brain glioma. While, all patients with brain glioma received radiotherapy after operation and their survival periods were followed up. METHODS： Primary lesion wax of brain glioma was cut into serial sections and stained with S-P immunohistochemical staining. Brown substance which was observed in tumor nucleus was regarded as the positive expressions of both proliferating cell nuclear antigen and P27 protein. Automatic imaging analytic system was used to quantitatively analyze staining results of tumor. MAIN OUTCOME MEASURES： To compare the expressions of proliferating cell nuclear antigen and P27 protein in brain glioma tissues and non-tumor brain tissues and investigate the effect of various sexes, ages, survival periods and severities on the expressions of them in brain tissues. RESULTS： There was no significant difference of sexes and ages in the expressions of proliferating cell nuclear antigen and P27 protein （P 〉 0.05）; however, the expressions of proliferating cell nuclear antigen and P27 protein were milder in non-tumor brain tissues than those in the brain glioma tissues （P 〈 0.05）. Expression of proliferating cell nuclear antigen in brain tissue of grade III- IV severity was stronger than that of grade I - II severity, and the expression in ≥ 5-year survival periods were also stronger than that in 〈 5-year survival periods （P 〈 0.05）. In addition, expression of P27 protein in brain tissue of grade III- IV severity was stronger than that of grade I - II severity, and the expression in ≥ 5-year survival periods were also stronger than that in 〈 5-year survival periods （P 〈 0.05）. CONCLUSION： Abnormal expressions of proliferating cell nuclear antigen and P27 protein in human brain glioma are closely related to onset, development and prognosis of tumor.

PROLIFERATING CELL NUCLEAR ANTIGEN(PCNA) IN OVARIAN CARCINOMA AND ITS RELATION TO LYMPH NODE METASTASIS AND PROGNOSIS

Objective: To investigate expression of proliferating cell nuclear antigen (PCNA) in ovarian epithelial cancer and its relation to lymph node metastasis, outcome of second look laparotomy (SLL) and prognosis Methods: Monoclonal antibody PC10 was used to stain PCNA in archival paraffin embedded tissues Results: PC10 immunostaining was performed successfully in all 74 primary and 31 intraperitoneal metastatic tumors The expression levels of PCNA were significantly increased in 31 metastatic tumors compared with their primary tumor from the same patients (7 94 vs 6 89, P=0 042) The expression levels was more elevated in bilateral than in unilateral ovarian cancer, but it was not associated with lymph node metastasis, clinical stage, histological grade and subtype In 28 patients with stage III ovarian cancer undergone SLL, the mean immunoreactive score (IRS) of PCNA of the primary tumor was significantly higher in patients with negative SLL than in those with positive SLL (7 59 vs 6 10, P =0 03) Since chemotherapy was performed following surgical debulking, negative SLL more frequently seen in patients with high PCNA expression might suggest better chemotherapeutic sensitivity due to higher proliferation fraction of tumor cell Univariate analysis of survival indicated that the overall survival was inversely associated with the level of PCNA expression, while multivariate analysis with Cox's model showed that independent prognostic factors were the residual tumor after primary debulking ( P<0 001 ) and clinical stage ( P <0 05), followed by PCNA expression( P =0 09) Conclusion: The expression of PCNA may beuseful in predicting the patients' prognosis, but is not correlated with lymph node metastasis

Construction of the Antisense Eukaryotic Vector for Proliferating Cell Nuclear Antigen Gene and Its Expression in Bladder Cancer EJ Cell Line

To explore a novel strategy for antisense gene therapy of cancer,the coding sequence of hum an proliferating cell nuclear antigen(PCNA) c DNA was reversely inserted into the eukaryotic vector p L XSN by molecular cloning techniques and transferred into bladder cancer EJcells with li- posome. The PCNA expression in transferred cells was dynamically detected by immunofluo- rescence and RT- PCR techniques. Changes of proliferation activities of cancer cells were assayed by MTT colorim etric and cloning formation m ethods.In the experiment,the antisense eukaryotic vector was successfully constructed and nam ed as p L APSN.After transfection with it for1- 7 days,PCNA protein and m RNA levels in cancer cells were blocked by16 .74 % - 84 .2 1% (P< 0 .0 5 ) and2 3.2 7% - 86 .15 % (P<0 .0 5 ) respectively.The proliferation activities of transferred cells were inhibited by 2 7.91% - 6 2 .0 7% (P<0 .0 1) ,with cloning formation abilities being de- creased by 5 0 .81% (P<0 .0 1) . Itwas concluded that the in vitro proliferation activities of cancer cells could be effectively inhibited by blocking PCNA expression with antisense technique,which could serve as an ideal strategy for gene therapy of bladder cancer.

Effects of UVB on the expression of proliferating cell nuclear antigen (PCNA) in dinoflagellate Prorocentrum donghaiense Lu

PCNA has been considered as a useful marker for the estimation of growth rates of marine phytoplankton at the species level. Since dinoflagellates are noted for having many prokaryotic features in that they are the only eukaryotes to have permanently condensed chromosomes as well as lacking histones and a nucleosome, the sensitivity to UVB radiation and the validity of PCNA as a maker of growth rate in dinoflagellate need to be evaluated. Prorocentrum donghaiense Lu was investigated to valuate the UVB sensitivity in relation to cellular and molecular aspects of PCNA as a growth indicator. The effects of UVB radiation on PCNA were studied using the methods of western blots technology and whole-cell immunoflurescence with one mono-antibody. UVB changed the cell morphology, halted the growth and increased the cell size, even caused cell death to a certain extent after treatment with UVB radiation in P. donghaiense. Compared with the control, treating the algal cultures in exponential phases with UVB radiation for 24 h caused chromatin release and increases in protein levels of PCNA.