Multifaceted p21 in carcinogenesis,stemness of tumor and tumor therapy

Cancer cells possess metabolic properties that are different from those of benign cells.p21,encoded by CDKN1A gene,also named p21Cip1/WAF1,was first identified as a cyclin-dependent kinase regulator that suppresses cell cycle G1/S phase and retinoblastoma protein phosphorylation.CDKN1A(p21)acts as the downstream target gene of TP53(p53),and its expression is induced by wild-type p53 and it is not associated with mutant p53.p21 has been characterized as a vital regulator that involves multiple cell functions,including G1/S cell cycle progression,cell growth,DNA damage,and cell stemness.In 1994,p21 was found as a tumor suppressor in brain,lung and colon cancer by targeting p53 and was associated with tumorigenesis and metastasis.Notably,p21 plays a significant role in tumor development through p53-dependent and p53-independent pathways.In addition,expression of p21 is closely related to the resting state or terminal differentiation of cells.p21 is also associated with cancer stem cells and acts as a biomarker for such cells.In cancer therapy,given the importance of p21 in regulating the G1/S and G2 check points,it is not surprising that p21 is implicated in response to many cancer treatments and p21 promotes the effect of oncolytic virotherapy.

Implication of HPV16 Infection and P21 Gene Mutation in the Carcinogenesis and Prognosis of Gastric Cancer

Objective： To investigate whether there is a synergistic carcinogenesis between the infection of human papilloma virus （HPV） and the P21 gene mutation in gastric cancer tissue and their relationship with prognosis of the patients with gastric cancer. Methods： By using PCR technique, HPV16 infection in 46 gastric cancer tissue samples was measured and by using immunohistochemical S-P method, the P21 gene mutation in gastric cancer was detected. All patients were regularly followed up for 3 years by writing letter or clinics, to detect the infection of HPV16 by PCR and the p21 gene mutation by immunohistochemical method in 46 gastric cancer tissue specimens. Results： The positive rate of HPV16 was 41.3% and the gene mutation rate of p21 was 52.17% respectively. The recurrence or remote metastasis was observed in 21 of 46 patients. The recurrence rate was 73.68% in the patients positive for HPV16 and 66.6% in those positive for p21 gene mutation. In 8 cases positive for both HPV16 and P21, 6 had recurrence or remote metastasis. Conclusion： The HPV16 infection may be one factor causing gastric cancer and it has a synergistic carcinogenesis with the p21gene mutation. The latter may be one of the prognostic indices in gastric cancer.

Alteration of p53 and p21 during hepatocarcinogenesis in tree shrews

AIM: To investigate p53 mutation and p21 expression in hepatocarcinogenesis induced by hepatitis B virus (HBV) and aflatoxin B1 (AFB1) in tree shrews, and to reveal the role of these genes in hepatocarcinogenesis.METHODS: Tree shrews were divided into four groups:group A, those infected with HBV and fed with AFB1 (n = 39);group B, those infected with HBV alone (n = 28); group C,those fed with AFB1 alone (n = 29); and group D, normal controls (n = 20). The tree shrews underwent liver biopsies once every 15 wk. Expression of p53 and p21 proteins and genes in the biopsies and tumor tissues of the experimental tree shrews was detected, respectively, by immunohistochemistry,and by Southem blotting and reverse transcription-polymerase chain reaction and sequencing.RESULTS: The incidence of hepatocellular carcinomas (HCC) was higher in group A (66.7%) than that in group B (3.57%) and C (30%). The time of HCC occurrence was also earlier in group A than that in group C (120.0±16.6 wk vs 153.3±5.8 wk, respectively, P<0.01). p53 protein was not detected by immunohistochemistry in all groups before the 75^th wk of the experiment. At the 105^th wk, the positive rates fo p53 were 78.6%, 60% and 71.4% in groups A, B and C, respectively, which were significantly higher than that in group D (10%) (all P<0.05). An abnormal band of p53 gene was observed in groups A and C. The mutation points of p53gene in tree shrews with HCC were at codons 275, 78 and 13. The nucleotide sequence and amino acid sequence of tree shrew's wild-type p53 showed 91.7% and 93.4% homologies with those of human p53,respectively. The immunopositivity for p21 was found before HCC development. The incidence of HCC was significantly higher in tree shrews that were positive for p21 than those negative for p21 (80.0% vs 11.0%, P<0.001).The incidence of HCC in p21 positive animals in group A was significantly higher than those positive for p21 in group C (P<O.05).CONCLUSION: A remarkable synergistic effect on HCC development exists between HBV and AFB1. p53 mutation promotes the development of HCC. HBV and AFB1 may synergistically induce p53 gene mutation, and stimulate ras gene expression, ras gene is activated at the earlier stage during hepatocarcinogenesis, p21 protein may be an early marker, and the alterations of p53 may be a late event in the development of HCC.

Oncogenic role of p21 in hepatocarcinogenesis suggests a new treatment strategy

A well-known tumor suppressor, p21, acts parado-xically by promoting tumor growth in some cellular conditions. These conflicting functions have been demonstrated in association with the HBx gene and in hepatocarcinogenesis. The molecular behavior of p21 depends on its subcellular localization. Nuclear p21 may inhibit cell proliferation and be proapoptotic, while cytoplasmic p21 may have oncogenic and anti-apoptotic functions. Because most typical tumor suppressive proteins also have different effects according to subcellular localization, elucidating the regulatory mechanisms underlying nucleo-cytoplasmic transport of these proteins would be significant and may lead to a new strategy for anti-hepatocellular carcinoma(HCC) therapy. Chromosome region maintenance 1(CRM1) is a major nuclear export receptor involved in transport of tumor suppressors from nucleus to cytoplasm. Expression of CRM1 is enhanced in a variety of malignancies and in vitro studies have shown the efficacy of specific inhibition of CRM1 against cancer cell lines. Interestingly, interferon may keep p21 in the nucleus; this is one of the mechanisms of its anti-hepatocarcinogenic function. Here we review the oncogenic property of p21, which depends on its subcellular localization, and discuss the rationale underlying a new strategy for HCC treatment and prevention.

Progress in research on correlation among STAT3, CyclinD1, P21 genes and tumors

Objective Along with changes in the ecology system and under the influence of various environmental factors, the incidence of tumor has been increasing year after year. There is a trend in cancer therapy to move to combined therapies involving surgery, radiation chemotherapy and gene therapy. Cancer gene therapy in recent years has brought new opportunities for treatment of tumor. Its advantages include low rate of tolerance, insensitivity to cell cycles, high specificity and coverage for both primary and metastatic tumors1＇2. However, this is a new field of clinical research. Regarding the correlation among the STAT3, CyclinD1 and P21 genes and tumors, research has focused on their expression and regulation. This article provides a summary of related research.

Changes of p53 and Waf1p21 and cell proliferation in esophageal carcinogenesis

AIM To study the correlationship between the changes of p53, Waf1p21 and the cell proliferation determined by PCNA at different stages of human esophageal carcinogenesis. METHODS Biopsied and resected esophageal tissues from a high risk population for esophageal cancer in northern China were used in this study. All the specimens were fixed with 85% alcohol and further processed with routine histology. The avidin biotin peroxidase complex (ABC) method was used for the detection of p53, Waf1p21 and PCNA. RESULTS The strong nuclear staining for p53, Waf1p21 and PCNA was observed in the normal esophageal epithelium and the epithelia with different severities of lesions. As the lesions progressed to dysplasia (DYS) and to esophageal squamons cell carcinoma (SCC), the percentage of Waf1p21 immunoreactivity decreased. The number of Waf1p21 immunostaining positive cells increased slightly from normal to basal cell hyperplasia (BCH), but there was no further increase in DYS and in SCC. The total number of positive cells for Waf1p21 stain appeared to be lower than that of p53 in normal and BCH esophageal epithelia and much lower in DYS and SCC. The Waf1p21 positive immunostaining cells were located at the third and forth cell layers in half of the samples examined, which was 2～4 cell layers higher than that of PCNA and p53 in the same histological categories of normal, BCH and DYS. CLNCLUSION The low levels of Waf1p21 at the stage of DYS may be related to a functional loss of p53. Other mechanisms may also be responsible to the lack of Waf1p21 expression in DYS and SCC.

LncRNA p21调控Hippo-YAP信号通路对小鼠腹主动脉瘤形成的影响及机制

目的 探究长链非编码RNA p21(long non-coding RNA,LncRNA p21)调控Hippo-Yes相关蛋白(Hippo-Yes-associated protein, Hippo-YAP)信号通路对小鼠腹主动脉瘤(abdominal aortic aneurysm, AAA)形成的影响。方法 C57BL/6 ApoE-/-通过皮下植入渗透性微泵构建血管紧张素Ⅱ(angiotensinⅡ,AngⅡ)诱导小鼠AAA模型。将C57BL/6 ApoE-/-随机分为假手术组(sham)、模型组(model)、LncRNA p21阴性对照组(sh-NC)、LncRNA p21敲低组(sh-LncRNA p21)。HE和血管弹力纤维染色(VVG)观察血管形态变化;qRT-PCR检测LncRNA p21表达;Western blot检测MMP-2、MMP-9、TIMP-1表达;原位末端标记法(TUNEL)染色检测平滑肌细胞凋亡;Western blot检测caspase-3、cyclinD1及Hippo-YAP信号通路蛋白表达。结果 与sham组相比,model组小鼠血管弹力纤维断裂紊乱,出现明显损伤,且LncRNA p21、MMP-2、MMP-9、caspase-3表达和细胞凋亡率均增加(P<0.01),TIMP-1、cyclinD1和YAP、TAZ表达均降低(P<0.01)。与model组相比,sh-LncRNA p21组小鼠血管弹力纤维断裂及损伤程度减轻,LncRNA p21、MMP-2、MMP-9、caspase-3表达和细胞凋亡率均降低(P<0.01),TIMP-1、cyclinD1和YAP、TAZ表达均增加(P<0.01)。结论 LncRNA p21能够促进小鼠AAA形成,其机制与调控Hippo-YAP信号、促进细胞凋亡、抑制细胞增殖相关。

血清lncRNA p21表达水平与PCI治疗急性心肌梗死患者预后的关系

目的研究血清lncRNA p21表达水平与经皮冠状动脉介入术(PCI)治疗急性心肌梗死患者预后的关系。方法选取2018年1月至2020年12月沭阳县中医院收治的102例PCI治疗的急性心肌梗死患者,患者术后随访1年,根据急性生理与慢性健康评分(APACHE-Ⅱ)将患者分为预后良好组和预后不良组,预后良好组72例,预后不良组30例。比较两组患者性别、身体质量指数(BMI)、高血压等一般临床资料,比较两组入院时肌钙蛋白(c Tnl)、肌酸激酶同工酶(CK-MB)水平以及治疗前后血清lncRNA p21表达情况,分析血清lncRNA p21表达与患者预后的关系。结果预后良好组患者合并慢性阻塞性肺疾病(COPD)、早发冠心病、合并自身免疫疾病百分比低于预后不良组,差异有统计学意义(P<0.05)。预后良好组入院时cTnl、CK-MB水平均低于预后不良组,差异有统计学意义(P<0.05)。治疗前预后良好组lncRNA p21表达水平高于预后不良组,治疗后两组lncRNA p21表达水平升高且预后良好组高于预后不良组,差异有统计学意义(P<0.05)。Logistic回归分析结果显示:高水平lncRNA p21与糖酵解酶的比值(lncRNA p21/GAPDH)表达是PCI治疗急性心肌梗死患者预后的保护因素,预后>60岁、合并COPD、早发冠心病、合并自身免疫疾病以及高水平CK-MB是PCI治疗急性心肌梗死患者预后的危险因素(P<0.05)。结论LncRNA-p21低表达可以加重心肌细胞及内皮细胞受损程度,内皮细胞损伤可能加重冠脉狭窄,不利于急性心肌梗死患者预后,血清高水平lncRNA p21表达水平是PCI治疗急性心肌梗死预后的保护因素。

Expression of IGF-Ⅱ,p53,p21 and HBxAg in precancerous events of hepatocarcinogenesis induced by AFBI and/or HBV in tree shrews

INTRODUCTIONIn order to study the relationship between oncogeneexpression and HCC generation,we observed theprecancerous hepatic GGT loci,IGF-Ⅱ,p53 andp21 expression during hepatocarcinogenesis of treeshrew induced by hepatitis B virus (HBV) and/oraflatoxin B1 (AFB1).

Antitumor Effect of Apcin on Endometrial Carcinoma via p21-Mediated Cell Cycle Arrest and Apoptosis

Objective Endometrial carcinoma(EC)is a prevalent gynecological malignancy characterized by increasing incidence and mortality rates.This underscores the critical need for novel therapeutic targets.One such potential target is cell division cycle 20(CDC20),which has been implicated in oncogenesis.This study investigated the effect of the CDC20 inhibitor Apcin on EC and elucidated the underlying mechanism involved.Methods The effects of Apcin on EC cell proliferation,apoptosis,and the cell cycle were evaluated using CCK8 assays and flow cytometry.RNA sequencing(RNA-seq)was subsequently conducted to explore the underlying molecular mechanism,and Western blotting and coimmunoprecipitation were subsequently performed to validate the results.Animal studies were performed to evaluate the antitumor effects in vivo.Bioinformatics analysis was also conducted to identify CDC20 as a potential therapeutic target in EC.Results Treatment with Apcin inhibited proliferation and induced apoptosis in EC cells,resulting in cell cycle arrest.Pathways associated with apoptosis and the cell cycle were activated following treatment with Apcin.Notably,Apcin treatment led to the upregulation of the cell cycle regulator p21,which was verified to interact with CDC20 and consequently decrease the expression of downstream cyclins in EC cells.In vivo experiments confirmed that Apcin treatment significantly impeded tumor growth.Higher CDC20 expression was observed in EC tissue than in nonmalignant tissue,and increased CDC20 expression in EC patients was associated with shorter overall survival and progress free interval.Conclusion CDC20 is a novel molecular target in EC,and Apcin could be developed as a candidate antitumor drug for EC treatment.

LncRNA p21通过介导Wnt/β-catenin信号通路在调控胃癌转移中作用和机制

目的研究LncRNA p21通过介导wntβ-catenin信号通路抑制人胃癌MGC-803细胞生长和转移的作用机制。方法观察人胃癌MGC-803细胞转染中慢病毒过表达LncRNA p21,并对其细胞体内外迁移、侵袭、细胞形态和增殖进行分析;检测wntβ-catenin信号通路是否直接参与了LncRNA p21介导的抑制胃癌细胞生长和增殖作用;wntβ-catenin信号通路使用LiC1进行验证。结果LncRNA p21过表达中胃癌MGC-803细胞出现星状形态较圆的低侵袭或纺锤状形态的改变;LncRNA p21在体内外均呈现抑制胃癌MGC-803细胞的生长和增殖,且wntβ-catenin信号通路介导了LncRNA p21对胃癌细胞MGC-803的增殖、侵袭和迁移作用。结论LncRNA p21可于体内外抑制胃癌MGC-803细胞的生长和转移,且LncRNA p21抑制主要通过抑制Wnt/β-catenin信号通路介导以起到抑制的作用。

急性心肌梗死患者血清lncRNA P21表达水平及临床意义

目的探究急性心肌梗死(AMI)患者血清lncRNA p21表达水平及临床意义。方法选取河南科技大学第一附属医院心外科2019年1月至2021年1月收治的92例AMI患者(AMI组),根据冠脉病变程度分为轻度病变组(n=29)、中度病变组(n=43)和重度病变组(n=20);同期选择本院体检健康者92例为对照组。AMI患者在经皮冠状动脉植入术(PCI)术后随访24个月,将患者分为心血管不良事件(MACE)组(n=22)和非MACE组(n=70)。采用实时荧光定量聚合酶链式反应检测研究对象血清中lncRNA P21表达水平。采用Pearson法分析AMI患者血清lncRNA p21水平与肌钙蛋白I(cTnI)、肌酸激酶同工酶(CK-MB)水平的相关性。采用受试者工作特征(ROC)曲线评价血清lncRNA P21水平预测AMI的价值。结果与对照组相比,AMI组血清lncRNA p21相对表达水平较低(P<0.05),CK-MB及cTnI水平较高(P<0.05)。与轻度病变组相比,中度病变组、重度病变组血清lncRNA P21相对表达水平较低(P<0.05),CK-MB、cTnI水平较高(P<0.05);与中度病变组相比,重度病变组血清lncRNA P21相对表达水平较低(P<0.05),CK-MB、cTnI水平较高(P<0.05)。AMI患者血清lncRNA p21水平与cTnI、CK-MB水平均呈负相关(P<0.05)。ROC曲线显示,lncRNA p21水平预测AMI的曲线下面积(AUC)为0.861,其灵敏度、特异度分别为70.70%,89.10%;lncRNA P21联合cTnI、CK-MB预测AMI的AUC为0.956,其灵敏度、特异度分别为89.10%、94.60%。与非MACE组相比,MACE组治疗前血清lncRNA P21相对表达水平较低(P<0.05)。结论AMI患者血清lncRNA p21表达水平下降,lncRNA p21对AMI具有一定的诊断价值。

Genes for RNA-binding proteins involved in neuralspecific functions and diseases are downregulated in Rubinstein-Taybi iNeurons

Taking advantage of the fast-growing knowledge of RNA-binding proteins(RBPs)we review the signature of downregulated genes for RBPs in the transcriptome of induced pluripotent stem cell neurons(iNeurons)modelling the neurodevelopmental Rubinstein Taybi Syndrome(RSTS)caused by mutations in the genes encoding CBP/p300 acetyltransferases.We discuss top and functionally connected downregulated genes sorted to“RNA processing”and“Ribonucleoprotein complex biogenesis”Gene Ontology clusters.The first set of downregulated RBPs includes members of hnRNHP(A1,A2B1,D,G,H2-H1,MAGOHB,PAPBC),core subunits of U small nuclear ribonucleoproteins and Serine-Arginine splicing regulators families,acting in precursor messenger RNA alternative splicing and processing.Consistent with literature findings on reduced transcript levels of serine/arginine repetitive matrix 4(SRRM4)protein,the main regulator of the neural-specific microexons splicing program upon depletion of Ep300 and Crebbp in mouse neurons,RSTS iNeurons show downregulated genes for proteins impacting this network.We link downregulated genes to neurological disorders including the new HNRNPH1-related intellectual disability syndrome with clinical overlap to RSTS.The set of downregulated genes for Ribosome biogenesis includes several components of ribosomal subunits and nucleolar proteins,such NOP58 and fibrillarin that form complexes with snoRNAs with a central role in guiding post-transcriptional modifications needed for rRNA maturation.These nucleolar proteins are“dual”players as fibrillarin is also required for epigenetic regulation of ribosomal genes and conversely NOP58-associated snoRNA levels are under the control of NOP58 interactor BMAL1,a transcriptional regulator of the circadian rhythm.Additional downregulated genes for“dual specificity”RBPs such as RUVBL1 and METTL1 highlight the links between chromatin and the RBP-ome and the contribution of perturbations in their cross-talk to RSTS.We underline the hub position of CBP/p300 in chromatin regulation,the impact of its defect on neurons’post-transcriptional regulation of gene expression and the potential use of epidrugs in therapeutics of RBP-caused neurodevelopmental disorders.

Study on the Function of ORF Genes of Porcine Circovirus-like Virus P1

[Objectives]This study was conducted to determine the functions of eight ORF genes of porcine circovirus-like virus P1.[Methods]The double-copy tandem molecular cloning of porcine circovirus-like virus P1 genome was used to construct molecular clones with eight ORFs deleted by DNA site-directed mutagenesis technology.After transfected into PK15 cells for a certain period of time,RNA were extracted and was used to verify whether the eight ORFs were deleted or not and used for gene microarry analysis.The GO functions and KEGG pathway enrichment of differentially expressed genes were analyzed.[Results]P1 ORF1 is mainly involved in the biological processes of defense response to virus,signal transduction,regulation of Rab GTPase activity,and lipid metabolic process,and involved in the molecular functions of protein phosphatase inhibitor activity,phosphatidylinositol phospholipase C activity,2 iron,2 sulfur cluster binding,phosphoric diester hydrolase activity,and Rab GTPase activator activity,and in the KEGG pathways of secretion of digestive gland and nervous system development.P1 ORF2 is mainly involved in the biological processes of positive regulation of leukocyte chemotaxis,positive regulation of cell proliferation,positive regulation of cell migration,defense response to virus,regulation of cell growth,and involved in the molecular functions of insulin-like growth factor binding,and chemokine activity,and in the KEGG pathways of cytosolic DNA-sensing pathway,RIG-I-like receptor signaling pathway,toll-like receptor signaling pathway,chemokine signaling pathway,and cytokines,cytokine-cytokine receptor interaction.The biological processes,molecular functions and related pathways involving P1 ORF3 and ORF5 are basically similar to those of ORF2.P1 ORF8 is mainly involved in the biological processes of purine ribonucleotide biosynthetic process,amino acid transport,defense response to virus,amino acid transmembrane transport,and involved in molecular functions of N6-(1,2-dicarboxyethyl)AMP AMP-lyase(fumarate-forming)activity,iron-sulfur cluster binding,amino acid transmembrane transporter activity.[Conclusions]The analysis of the ORF functions of P1 virus lays a foundation for the study of its pathogenicity and pathogenesis.

鼻咽癌p53 p21^(WAF1)和MDM2蛋白异常表达的临床意义

目的:探讨p53、p21WAF1、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、p21WAF1和MDM2蛋白的表达状况。结果:1)p53、p21WAF1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p21WAF1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;p21WAF1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p21WAF1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p21WAF1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,p21WAF1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作为预测NPC复发倾向和临床预后的参考指标;如同时检测p53、MDM2和p21WAF1蛋白的两项或三项指标,预测意义更理想。

喉癌切缘组织中p53 p21及PCNA表达及其与肿瘤复发的关系

目的:研究早期喉癌手术切缘阴性组织中p53、p21及PCNA表达的相关性及其与肿瘤复发的关系。方法:选取唐山市协和医院2004年1月至2010年12月间92例早期喉癌患者为研究对象,采用免疫组织化学法联合检测肿瘤及其切缘组织中p53、p21及PCNA的表达情况。电话随访2年以上,对患者生存及肿瘤复发情况进行观察。结果:p53、p21及PCNA蛋白在喉癌组织中的表达与肿瘤的分级及分期无关。92例喉癌患者术后2年内有16例出现复发,复发率为17.39%。喉癌阴性切缘复发和未复发标本中p53、p21及PCNA蛋白表达阳性的切缘复发率分别为50.00%、34.21%和33.33%,明显高于p53、p21及PCNA蛋白表达阴性的切缘(8.33%、5.56%和9.68%)。经统计学分析,喉癌复发标本3种蛋白切缘阳性率明显高于未复发标本,均有显著性差异(P<0.01)。此外,喉癌阴性切缘组织中p53与p21蛋白的表达有明显的相关性,PCNA的表达与p21的表达亦有明显的相关性。结论:早期喉癌手术病理阴性切缘组织中的p53、p21及PCNA是患者预后的重要生物学标志,联合检测喉癌切缘组织中p53、p21及PC-NA的表达有望作为预测喉癌复发的指标。

p16^(INK4)与ras p21在青、老年人胃癌中表达的对比研究

目的：对青老年人胃癌中ｐ１６ＩＮＫ４及ｒａｓｐ２１的表达进行研究，在分子生物学水平上探讨青老年人胃癌的发病学之异同。方法：应用过氧化酶标记的链霉卵白素（ＳＰ）染色法对６５例胃癌（其中青年组３５例，老年组３０例）进行免疫组化染色。由两位研究者对染色结果进行观察，采用已知的乳腺癌阳性切片作为对照。所有数据进行χ２检验。结果：在非选择人群，ｐ１６ＩＮＫ４和ｒａｓｐ２１在胃癌中的阳性表达率分别为３６．９％，７５．４％；ｐ１６ＩＮＫ４的阳性表达率随着胃癌分化程度的降低、浸润深度的加深而增高并与淋巴结转移有关；而ｒａｓｐ２１的阳性表达率随胃癌的分化程度降低而降低。ｐ１６ＩＮＫ４在青年人胃癌中的阳性率（６０％）显著高于老年人（１０％）（Ｐ＜０．０５），而ｒａｓｐ２１在前者的阳性率（６２．８％）则显著低于后者（９０％）（Ｐ＜０．０５）。结论：ｐ１６ＩＮＫ４表达的检测在判断胃癌的恶性程度及淋巴结转移趋势方面具有一定的参考价值。在判断胃癌的恶性程度方面，ｒａｓｐ２１具有一定的参考价值。青老年人胃癌的发病学不尽相同。

抗CD44单抗A3D8对HL-60细胞Cyclin D1 CDK4 p21cip1表达的影响

目的:探讨CD44单克隆抗体A3D8对人急性髓系白血病细胞株HL-60细胞增殖分化影响的分子作用机制。方法:采用FCM、RT-PCR及Westernblot方法检测A3D8作用前后HL-60细胞CyclinD1、CDK4、p21cip1表达的变化。结果:A3D8作用使HL-60细胞发生G0/G1期阻滞。A3D8下调HL-60细胞CyclinD1及CDK4的表达,上调HL-60细胞p21cip1mRNA及P21蛋白表达。结论:A3D8抑制HL-60细胞增殖、诱导其分化的分子机制可能与p21cip1表达上调及CyclinD1、CDK4表达下调有关。

胃癌及癌前病变ras P21,P53的表达意义

近年来的研究结果揭示,胃癌的发生是一个涉及多种癌基因、抑癌基因及多阶段累积的复杂过程,其中癌基因rasp21及抑癌基因p53是与胃癌发生有关的癌相关基因。我们采用SP免疫组化法,同步检测ras p21及p53,观察二种基因蛋白产物在胃癌及癌前病变中的表达情况,以探讨ras癌基因及p53基因在胃癌发生中的作用及意义。 1 材料和方法 1.1 材料胃粘膜活检组织经病理诊断的胃癌42例,不典型增生23例,肠上皮化生26例,慢性萎缩性胃炎14例,慢性浅表性胃炎24例,用100mL·L^(-1)福尔马林液固定,常规组织脱水,石蜡包埋,4μm连续切片。鼠抗人ran P21单克隆抗体及鼠抗人P53单克隆抗体均为美国Maxim Biotech公司产品,试剂盒购自福州迈新生物技术开发公司。 1.2 方法应用免疫组化(SP法)染色,测定方法按试剂盒说明书进行。ras P21蛋白阳性表现为细胞质染色呈棕黄色;P53蛋白阳性表现为细胞核染色呈棕黄色至深棕黄色。