Molecular mechanism underlying the functional loss of cyclindependent kinase inhibitors p16 and p27 in hepatocellular carcinoma

Hepatocellular carcinoma （HCC） is one of the most common human cancers, and its incidence is still increasing in many countries. The prognosis of HCC patients remains poor, and identification of useful molecular prognostic markers is required. Many recent studies have shown that functional alterations of cellcycle regulators can be observed in HCC. Among the various types of cell-cycle regulators, p16 and p27 are frequently inactivated in HCC and are considered to be potent tumor suppressors, p16, a G1-specific cell-cycle inhibitor that prevents the association of cyclindependent kinase （CDK） 4 and CDK6 with cyclin DI, is frequently inactivated in HCC via CpG methylation of its promoter region, p16 may be involved in the early steps of hepatocarcinogenesis, since p16 gene methylation has been detected in subsets of pre-neoplastic liver cirrhosis patients, p27, a negative regulator of the G1-S phase transition through inhibition of the kinase activities of Cdk2/cyclin A and Cdk2/cyclin E complexes, is now considered to be an adverse prognostic factor in HCC. In some cases of HCC with increased cell proliferation, p27 is overexpressed but inactivated by sequestration into cyclin D1-CDK4-containing complexes. Since loss of p16 is closely related to functional inactivation of p27 in HCC, investigating both p16 and p27 may be useful for precise prognostic predictions in individuals with HCC.

Interleukin-1 beta up-regulates tissue inhibitor of matrix metalloproteinase-1 mRNA and phosphorylation of c-jun N-terminal kinase and p38 in hepatic stellate cells

AIM： To study the relationship between interleukin-lbeta （IL-1β） up-regulating tissue inhibitor of matrix metalloproteinase-1 （TIMMP-1） mRNA expression and phosphorylation of both c-jun N-terminal kinase （INK） and p38 in rat heffatic stellate cells （HSC）. METHODS： RT-PCR was performed to measure the expression of TIMMP-1 mRNA in rat HSC. Western blot was performed to measure IL-1β-induced JNK and p38 activities in rat HSC. RESULTS： TIMMP-1 mRNA expression （1.191± 0.079） was much higher after treatment with IL-1β （10 ng/mL） for 24 h than in control group （0.545±0.091） （P〈0.01）. IL-1β activated INK and p38 in a time-dependent manner. After stimulation with IL-1β for 0, 5, 15, 30, 60 and 120 min, the INK activity was 0.982±0.299, 1.501±0.720, 2.133±0.882, 3.360±0.452, 2.181±0.789, and 1.385 ± 0.368, respectively. There was a significant difference in JNK activity at 15 min （P〈 0.01）, 30 min （P〈 0.01） and 60 min （P〈0.01） in comparison to that at 0 min. The p38 activity was 1.061±0.310, 2.050±0.863, 2.380±0.573, 2.973±0.953, 2.421±0.793, and 1.755 ± 0.433 at the 6 time points （0, 5, 15, 30, 60 and 120 min） respectively. There was a significant difference in p38 activity at 5 min （P〈0.05）, 15 min （P〈0.01）, 30 min （P〈0.01） and 60 min （P〈0.01） compared to that at 0 min. TIMMP-1 mRNA expression trended to decrease in 3 groups pretreated with different concentrations of SP600125 （10 μmol/L, 1.022±0.113; 20 μmol/L, 0.869±0.070; 40 μmol/L, 0.666±0.123）. Their decreases were all significant （P〈0.05, P〈0.01, P〈0.01） in comparison to control group （without SP600125 treatment, 1.163±0.107）. In the other 3 groups pretreated with different concentrations of SB203580 （10 μmol/L, 1.507±0.099; 20 μmol/L, 1.698±0.107; 40 μmol/L, 1.857±0.054）, the expression of TIMMP-1 mRNA increased. Their levels were higher than those in the control group （without SB203580 treatment, 1.027 ± 0.061） with a significant statistical significance （P〈 0.01）. CONCLUSION： IL-1β has a direct action on hepatic fibrosis by up-regulating TIMMP-1 mRNA expression in ratessionin in rate HSC.JNK and p38 mitogen-activated protein kinases （MAPKs） are involved in IL-1β-induced TIMMP-1 gene expression, and play a distinct role in this process, indicating that p38 and .INK pathways cooperatively mediate TIMP-1 mRNA expression in rat HSC.

Axonal growth inhibitors and their receptors in spinal cord injury:from biology to clinical translation

Axonal growth inhibitors are released during traumatic injuries to the adult mammalian central nervous system, including after spinal cord injury. These molecules accumulate at the injury site and form a highly inhibitory environment for axonal regeneration. Among these inhibitory molecules, myelinassociated inhibitors, including neurite outgrowth inhibitor A, oligodendrocyte myelin glycoprotein, myelin-associated glycoprotein, chondroitin sulfate proteoglycans and repulsive guidance molecule A are of particular importance. Due to their inhibitory nature, they represent exciting molecular targets to study axonal inhibition and regeneration after central injuries. These molecules are mainly produced by neurons, oligodendrocytes, and astrocytes within the scar and in its immediate vicinity. They exert their effects by binding to specific receptors, localized in the membranes of neurons. Receptors for these inhibitory cues include Nogo receptor 1, leucine-rich repeat, and Ig domain containing 1 and p75 neurotrophin receptor/tumor necrosis factor receptor superfamily member 19(that form a receptor complex that binds all myelin-associated inhibitors), and also paired immunoglobulin-like receptor B. Chondroitin sulfate proteoglycans and repulsive guidance molecule A bind to Nogo receptor 1, Nogo receptor 3, receptor protein tyrosine phosphatase σ and leucocyte common antigen related phosphatase, and neogenin, respectively. Once activated, these receptors initiate downstream signaling pathways, the most common amongst them being the Rho A/ROCK signaling pathway. These signaling cascades result in actin depolymerization, neurite outgrowth inhibition, and failure to regenerate after spinal cord injury. Currently, there are no approved pharmacological treatments to overcome spinal cord injuries other than physical rehabilitation and management of the array of symptoms brought on by spinal cord injuries. However, several novel therapies aiming to modulate these inhibitory proteins and/or their receptors are under investigation in ongoing clinical trials. Investigation has also been demonstrating that combinatorial therapies of growth inhibitors with other therapies, such as growth factors or stem-cell therapies, produce stronger results and their potential application in the clinics opens new venues in spinal cord injury treatment.

skp2、p27^(kip1)在正常胃黏膜和胃癌组织中的表达

[目的]探讨细胞S相激酶相关蛋白2(skp2)和细胞周期素依赖性激酶抑制蛋白27(p27kip1)表达与胃癌发生的关系。[方法]用免疫组化SP法检测69例胃癌组织中skp2、p27kip1蛋白的表达,并与28例正常胃黏膜作对比;用RT-PCR方法随机检测其中3例胃癌组织中skp2的mRNA表达,并与其正常胃黏膜作对比。[结果]p27kip1蛋白阳性表达率在胃癌中为46.38%,而正常胃组织中为96.43%(P<0.01)。p27kip1蛋白在胃癌中的阳性表达率随肿瘤分化程度的降低、浸润深度的加深、淋巴结转移、病理分期进展而降低(P<0.05)。skp2mRNA在胃癌组织中的表达明显上调(P<0.01)。skp2蛋白阳性表达率在胃癌中为33.33%,而正常胃组织中为10.71%(P<0.05)。skp2蛋白阳性表达率随肿瘤的分化程度降低而升高(P<0.05)。skp2、p27kip1蛋白在胃癌中的表达呈负相关(P<0.01)。[结论]p27kip1、skp2蛋白检测有助于胃癌的临床诊断及判断预后。

乳腺癌组织中PTEN、MMP-9及p27^(kip1)表达及意义分析

目的分析第10号染色体缺失的磷酸酶及张力蛋白(phosphatase and tensin homolog deleted on chro-mosome ten,PTEN)、基质金属蛋白酶-9(matrix metalloproteinase-9,MMP-9)、细胞周期蛋白依赖性激酶抑制蛋白27(cyclin dependent kinase inhibitor protein 27,p27^(kip1))在乳腺癌组织中的表达情况,讨论其在乳腺癌发生、发展中的意义。方法选取2014年2月至2016年2月本院肿瘤科和乳腺外科收治的55例乳腺癌患者(乳腺癌组)和35例乳腺良性病变患者(乳腺良性病变组)为研究对象。采用免疫组织化学SP法检测入选患者PTEN、MMP-9、p27^(kip1)的表达水平。结果乳腺良性病变组PTEN和p27^(kip1)的表达率(82.86%,85.71%)均显著高于乳腺癌组(45.45%,43.64%)(P<0.05),MMP-9的表达率(42.86%)显著低于乳腺癌组(69.09%)(P<0.05)。乳腺癌组织中PTEN的表达与MMP-9的表达呈负相关(r=-0.587,P<0.05),与p27^(kip1)的表达呈正相关(r=0.532,P<0.05)。结论 PTEN与p27^(kip1)表达异常可能与乳腺癌的发生、发展及预后相关。MMP-9参与乳腺癌的发生、发展,可作为评估乳腺癌浸润和转移的生物学指标。

Stress kinase inhibition modulates acute experimental pancreatitis

AIM: To examine the role of p38 during acute experimental cerulein pancreatitis. METHODS: Rats were treated with cerulein with or without a specific JNK inhibitor (CEP1347) and/or a specific p38 inhibitor (SB203580) and pancreatic stress kinase activity was determined. Parameters to assess pancreatitis included trypsin, amylase, lipase, pancreatic weight and histology. RESULTS: JNK inhibition with CEP1347 ameliorated pancreatitis, reducing pancreatic edema. In contrast, p38 inhibition with SB203580 aggravated pancreatitis with higher trypsin levels and, with induction of acinar necrosis not normally found after cerulein hyperstimulation. Simultaneous treatment with both CEP1347 and SB203580 mutually abolished the effects of either compound on cerulein pancreatitis. CONCLUSION: Stress kinases modulate pancreatitis differentially. JNK seems to promote pancreatitis development, possibly by supporting inflammatory reactions such as edema formation while its inhibition ameliorates pancreatitis. In contrast, p38 may help reduce organ destruction while inhibition of p38 during induction of cerulein pancreatitis leads to the occurrence of acinar necrosis.

Insulin-like growth factor binding protein-5 influences pancreatic cancer cell growth

AIM： To investigate the functional significance of insulin-like growth factor binding protein-5 （IGFBP-5） overexpression in pancreatic cancer （PaC）.METHODS： The effects of IGFBP-5 on cell growth were assessed by stable transfection of BxPC-3 and PANC-1 cell lines and measuring cell number and DNA synthesis. Alterations in the cell cycle were assessed by flow cytometry and immunoblot analyses. Changes in cell survival and signal transduction were evaluated after mitogen and phosphatidylinositol activated protein kinase 3-kinase （PI3K） inhibitor treatment.RESULTS： After serum deprivation, IGFBP-5 expression increased both cell number and DNA synthesis in BxPC-3 cells, but reduced cell number in PANC-1 cells. Consistent with this observation, cell cycle analysis of IGFBP-5-expressing cells revealed accelerated cell cycle progression in BxPC-3 and G2/M arrest of PANC-1 cells. Signal transduction analysis revealed that Akt activation was increased in BxPC-3, but reduced in PANC-1 cells that express IGFBP-5. Inhibition of PI3K with LY294002 suppressed extracellular signal-regulated kinase-1 and -2 （ERK1/2） activation in BxPC-3, but enhanced ERK1/2 activation in PANC-1 cells that express IGFBP-5. When MEK1/2 was blocked, Akt activation remained elevated in IGFBP-5 expressing PaC cells; however, inhibition of PI3K or MEK1/2 abrogated IGFBP-5-mediated cell survival.CONCLUSION： These results indicate that IGFBP-5 expression affects the cell cycle and survival signal pathways and thus it may be an important mediator of PaC cell growth.

p21 and p27 immunoexpression in gastric well differentiated endocrine tumors(ECL-cell carcinoids)

AIM： To investigate the expression of cyclin-dependent kinase inhibitors p21 and p27 in gastric well differentiated endocrine tumors （GWDET） （ECLocell carcinoids）.METHODS： The expressions of p21 and p27 were examined immunhistochemically in endoscopic biopsy specimens from 16 patients matching the diagnostic criteria of GWDET. Percentage of positive nuclear staining either weak or strong was noted. The association of immunoexpressions with age, gender, tumor localization, multifocality and accompanying chronic atrophic gastritis, neuroendocrine cell hyperplasia （NEH）, neuroendocrine dysplasia （NED）, intestinal metaplasia （IM）, Ki-67 proliferation index and clinical outcome were also evaluated.RESULTS： All cases expressed p27 with a mean expression score of 43.6%, while 31.3% of the cases showed any p21 expression, p21 and p27 immunoexpressions were significantly correlated with each other （P 〈 0.01）, and the p21-expressing group had higher p27 expression scores （68% vs 22%）. p21 and p27 expressions were lower in women, in non-atrophic mucosa and cases whose tumors were located somewhere other than fundus without submucosal extension. On contrary, p21 and p27 expressions were higher in males and the patients with submucosal extension and atrophic gastritis. Cases presenting lower p27 scores had solitary tumors showing neither NEH-NED nor IM. Despite, cases with lower p21 expression presented multifocal tumors accompanied by NEH-NED. However, no correlation of p21 and p27 expressions was found with age and Ki-67 expression.CONCLUSION： p27 is widely expressed in GWDETs, while p21 expression is sparse and observed in two thirds of the cases. Loss of p21 and p27 expressions may be correlated with different carcinoid tumor subtypes; however,more studies are needed to assess the role of these prospective markers in gastrointestinal endocrine tumors.

Epidermal growth factor upregulates Skp2/Cks1 and p27^(kip1) in human extrahepatic cholangiocarcinoma cells

AIM:To evaluate the expression status of S-phase kinase-associated protein 2(Skp2)/cyclin-dependent kinases regulatory subunit 1(Cks1)and p27kip1,and assess the prognostic significance of Skp2/Cks1 expression with p27kip1in patients with extrahepatic cholangiocarcinoma.METHODS:Seventy-six patients who underwent curative resection for histologically confirmed extrahepatic cholangiocarcinoma at our institution from December1994 to March 2008 were enrolled.Immunohistochemical staining for Skp2,Cks1,p27kip1,and Ki67,along with other relevant molecular biologic experiments,were performed.RESULTS:By Cox regression analyses,advanced age(>65 years),advanced AJCC tumor stage,poorly differentiated histology,and higher immunostaining intensity of Skp2 were identified as independent prognostic factors in patients with extrahepatic cholangiocarcinoma.Exogenous epidermal growth factor(EGF,especially 0.1-10 ng/mL)significantly increased the proliferation indices by MTT assay and the mRNA levels of Skp2/Cks1 and p27kip1in SNU-1196,SNU-1079,and SNU-245 cells.The protein levels of Skp2/Cks1(from nuclear lysates)and p27kip1(from cytosolic lysate)were also significantly increased in these cells.There were significant reductions in the protein levels of Skp2/Cks1and p27kip1(from nuclear lysate)after the treatment of LY294002.By chromatin immunoprecipitation assay,we found that E2F1 transcription factor directly binds to the promoter site of Skp2.CONCLUSION:Higher immunostaining intensity of Skp2/Cks1 was an independent prognostic factor for patients with extrahepatic cholangiocarcinoma.EGF upregulates the mRNA and protein levels of Skp2/Cks1and p27kip1via the PI3K/Akt pathway and direct binding of E2F1 transcription factor with the Skp2 promoter.

特异性p^(38)MAPK抑制剂SB203580对乳鼠小脑颗粒神经元的保护作用

目的 研究 p38丝裂原激活蛋白激酶 (MAPK)选择性抑制剂SB2 0 35 80对乳鼠小脑颗粒神经元凋亡的保护作用。方法 SD乳鼠小脑颗粒神经元培养 ,琼脂糖凝胶电泳 ,SAPK/JNK分析试剂盒作激酶分析。结果 PI 3 K的特异性抑制剂LY2 940 0 2诱导小脑颗粒神经元凋亡 ,但SB2 0 35 80通过抑制细胞凋亡而促进小脑颗粒神经元的存活 ,且有浓度依赖性。LY2 940 0 2诱导凋亡的颗粒神经元中c Jun的表达量和磷酸化水平均升高 ,JNK被激活。但是 ,当小脑颗粒神经元生长在含SB2 0 35 80的高钾培养基中 ,c Jun的表达量、磷酸化水平和JNK的活性都明显的降低。结论 SB2 0 35 80通过抑制JNK的活性 ,降低c Jun的表达和磷酸化水平 。

UO-126对HeLa细胞增殖及对FBW7表达的影响

目的:观察UO-126对人类宫颈癌细胞株HeLa细胞增殖及对F-盒和含蛋白7的WD重复结构域FBW7表达的影响。方法:采用MTT法观察不同浓度的UO-126对HeLa细胞增殖的影响;免疫荧光法检测FBW7在HeLa细胞中的定位和表达;RT-PCR、Western blot检测FBW7 mRNA及蛋白在UO-126阻断丝裂原活化蛋白激酶(mitogen-activated protein ki-nases,MAPK)信号通路前后的表达情况。结果:MTT结果显示各浓度UO-126具有抑制HeLa细胞增殖的作用,且具有剂量依赖性和时间依赖性(P<0.05)。免疫荧光检测显示UO-126处理HeLa细胞后FBW7阳性表达增强。RT-PCR及West-ern blot结果显示,UO-126作用后HeLa细胞FBW7 mRNA及蛋白表达水平较未处理HeLa细胞明显增高(P<0.05)。结论:MAPK信号通路阻断剂UO-126抑制HeLa细胞增殖,FBW7位于MAPK信号通路的下游。

The involvement of p38 MAPK in transforming growth factor β1-induced apoptosis in murine hepatocytes

We reported in this manuscript that TGF-beta1 induces apoptosis in AML12 murine hepatocytes, which is associated with the activation of p38 MAPK signaling pathway. SB202190, a specific inhibitor of p38 MAPK, strongly inhibited the TGF-beta1-induced apoptosis and PAI-1 promoter activity. Treatment of cells with TGF-beta1 activates p38. Furthermore, over-expression of dominant negative mutant p38 also reduced the TGF-beta1-induced apoptosis. The data indicate that the activation of p38 is involved in TGF-beta1-mediated gene expression and apoptosis.

Effects of histone acetylation and DNA methylation on p21^(WAF1)regulation

Cell cycle progression is regulated by interactions between cyclins and cyclin-dependent kinases (CDKs). p21(WAF1) is one of the CIP/KIP family which inhibits CDKs activity. Increased expression of p21(WAF1) may play an important role in the growth arrest induced in transformed cells. Although the stability of the p21( WAF1) mRNA could be altered by different signals, cell differentiation and numerous influencing factors. However, recent studies suggest that two known mechanisms of epigenesis, i.e.gene inactivation by methylation in promoter region and changes to an inactive chromatin by histone deacetylation, seem to be the best candidate mechanisms for inactivation of p21( WAF1). To date, almost no coding region p21(WAF1) mutations have been found in tumor cells, despite extensive screening of hundreds of various tumors. Hypermethylation of the p21(WAF1) promoter region may represent an alternative mechanism by which the p21(WAF1/CIP1) gene can be inactivated. The reduction of cellular DNMT protein levels also induces a corresponding rapid increase in the cell cycle regulator p21(WAF1) protein demonstrating a regulatory link between DNMT and p21(WAF1) which is independent of methylation of DNA. Both histone hyperacetylation and hypoacetylation appear to be important in the carcinoma process, and induction of the p21(WAF1) gene by histone hyperacetylation may be a mechanism by which dietary fiber prevents carcinogenesis. Here, we review the influence of histone acetylation and DNA methylation on p21(WAF1) transcription, and affection of pathways or factors associated such as p 53, E2A, Sp1 as well as several histone deacetylation inhibitors.

MG132 Induced Apoptosis Pathway in HL-60 Cells and Impact of Allogeneic Mixed Lymphocyte Reaction

Objective： To investigate the proteasome inhibitor MG132-induced apoptosis pathway in HL-60 cells and the role of allogeneic mixed lymphocyte reaction. Methods： Cell apoptosis was analyzed by flow cytometry. The expressions of p21 protein, p27 protein and p53 protein in HL-60 ceils treated with MG132 were measured by Western blot. The proliferation of, peripheral blood mononuclear cells （PBMNCs） after treatment with 75 Gy irradiated HL-60 cells treated with MG132 was measured with CCK-8. Results： High-dose MG132 induced apoptosis in HL-60 cells. No significant change was observed in MG132-induced apoptosis after inhibiting caspase-8 and caspase-9 pathway. The expressions of p21 protein and p27 protein increased in MG132-induced apoptosis. HL-60 cells treated with low-dose MG132 improved the proliferation of PBMNCs from healthy volunteers. Conclusion： High-dose MG132 induced apoptosis and directly killed HL-60 ceils. MG132 induced apoptosis in a caspase-8- and caspase-9-independent pathway, p21 protein and p27 protein were involved in MG132-induced apoptosis in HL-60 cells. HL-60 cells treated with Low-dose MG132 improved the effect of promoting the proliferation of PBMNCs from healthy volunteers.

Effects of an Engineered Anti-HER2 Antibody chA21 on Invasion of Human Ovarian Carcinoma Cell In Vitro

Objective： HER-2 plays an important role in the development and progression of ovarian carcinoma. A number of monoclonal antibodies （MAbs） and engineered antibody fragments （such as scFvs） against the subdomain II or IV of HER-2 extracellular domain （ECD） have been developed. We investigated the effect of chA21, an engineered anti-HER-2 antibody that bind primarily to subdomain I, on ovarian carcinoma cell invasion in vitro, and explored its possible mechanisms. Methods： Growth inhibition of SK-OV-3 cells was assessed using a Methyl thiazolyl tetrazolium （MTT） assay. The invasion ability of SK-OV-3 was determined by a Transwell invasion assay. The expression of matrix metalloproteinase-2 （MMP-2） and its tissue inhibitors （TIMP-2） was detected by immunocytochemical staining, and the expression of p38 and the phosphorylation of p38 were assayed by both immunocytochemistry and Western blot. Results： After treatment with chA21, the invasion of human ovarian cancer SK-OV-3 cells was inhibited in dose- and time-dependent manners. Simultaneously the expression of p38, phospho-p38, MMP-2 and the MMP-2/TIMP-2 ratio decreased, while TIMP-2 expression increased. Additionally, the decrease in phospho-p38 was much greater than that of p38. Conclusion： chA21 may inhibit SK-OV-3 cell invasion via the signal transduction pathway involving MMP-2, TIMP-2, p38 and the activation of p38MAPK.

Expression of positive and negative regulators of cell cycle during wound healing

OBJECTIVE: To detect the expression of cell cycle positive regulators cyclin D(1), cyclin E, CDK(2), CDK(4) and negative regulators p21(cip1), p27(kip1), p16(ink4a) and p15(ink4b) during wound healing in rats. METHODS: Open wounds of full-thickness skin, diameter 1.8 cm, on rat backs were used as the wound model. Wound tissues were harvested on postwounding days 3, 5, 7, 9, 11, 14, 21 and 30. Ki67 expression in granulation tissue was detected by immunohistochemical assay. The patterns of the expression of cyclin D(1), cyclin E, CDK(2), CDK(4) and p21(cip1), p27(kip1), p16(ink4a), p15(ink4b) were detected by Western blot. RESULTS: Cell proliferation in granulation tissue took place predominantly within the first week after injury, with the proliferation peak occurring at postwounding day 5. There were no dramatic variations in the expression of cyclin D(1), CDK(2) and CDK(4) during wound healing. Up-regulated cyclin E was maintained from day 3 to 11 after injury, and then was down-regulated. No expression of p16(ink4a) and p15(ink4b) was found. p21(cip1) was expressed only from day 7 to 14, with peak expression observed on day 9. Constitutive p27(kip1) was expressed throughout wound healing with low levels in the proliferating period of day 3 to 5 and with increased levels in the post-mitotic and remodeling stage. The expression of p21(cip1) and p27(kip1) showed an inverse gradient to that of Ki67. CONCLUSION: p21(cip1) and p27(kip1) play a supervising role in preventing the hyperproliferative tendency in tissue repair.

细胞周期蛋白依赖性激酶抑制蛋白27基因在胃癌中表达及其与启动子甲基化的关系

目的探讨细胞周期蛋白依赖性激酶抑制蛋白27（p27^KiP1）在胃癌中的表达及其与基因启动子甲基化的关系。方法采用免疫组织化学链霉菌抗生物素蛋白．过氧化物酶（SP）法检测97例胃癌标本p27^KiP1蛋白的表达，并选取25例正常胃黏膜组织作对照，同时应用甲基化特异性聚合酶链反应（MSP）方法对启动子甲基化进行检测。结果正常胃黏膜组织中p27^KiP1蛋白表达率明显高于胃癌组（X2=31．02，P〈0．01）。在高／中分化组、黏膜层／黏膜下层组和无淋巴结转移的病例中，p27^KiP1蛋白表达率分别为66．67％（30／45）、92．86％（13／14）、79．07％（34／43），但随着胃癌分化程度的降低，侵及肌层／浆膜层或发生淋巴结转移，p27^KiP1蛋白表达率明显降低，分别为30．77％（16／52）、39．76％（33／83）、22．22％（12／54）（，值分别为12．47、13．55、31．03，P〈0．01）。46例p27^KiP1蛋白高表达病例中仅有5例出现启动子甲基化，而在51例p27^KiP1蛋白低表达病例中启动子甲基化高达21例（X2=11．32，P〈0．01）。结论p27^KiP1与胃癌发生发展密切相关。p27^KiP1蛋白表达降低常提示胃癌的低分化、高侵袭转移能力。p27^KiP1基因启动子甲基化可以引起p27^KiP1蛋白表达下调或缺失．与胃癌的发牛发展密切相关．

B细胞淋巴瘤／白血病-2相关X蛋白和细胞周期蛋白依赖性激酶抑制蛋白27在中心型软骨肉瘤组织的表达及临床意义

目的研究中心型软骨肉瘤（Central chondrosarcoma）中B细胞淋巴瘤／白血病12相关X蛋白（bax）及细胞周期蛋白依赖性激酶抑制蛋白27（p27^kipl）蛋白的表达与病理分级及预后的关系，并探讨两者表达的临床意义。方法选取60例确诊的中心型软骨肉瘤患者，术后随访超过5年，按照病理分型及预后对其病理标本分别进行分组，并选用20例非肿瘤软骨标本作为对照，采用免疫组织化学法检测上述标本中bax和p27^kipl蛋白的表达。结果60例中心型软骨肉瘤中，bax蛋白各级别间阳性表达率分别为Ⅰ级90％、Ⅱ级78．9％、Ⅲ级66．7％，差异有统计学意义（P〈0．05），在不同预后组中bax蛋白阳性表达率分别为治愈组80．0％、复发组75．0％、转移组75．0％，差异无统计学意义（P〉0．05）；p27^kipl州蛋白各级别阳性表达率分别为Ⅰ级90％、Ⅱ级70．9％、Ⅲ级61．9％，差异有统计学意义（P〈0．05），在不同预后分组中p27^kipl蛋白阳性表达率分别为治愈组80．4％、复发组66．7％、转移组37．5％，差异亦有统计学意义（P〈0．05）。结论bax及p27^kipl蛋白的表达与中心型软骨肉瘤的病理分级明显相关，但bax不能作为判断预后的指标，而p27^kipl蛋白则可作为判断预后的指标。

Jab1与头颈肿瘤

p27Kip1是一种细胞周期抑制剂,其低表达与肿瘤的不良预后密切相关,被认为是一种抑癌基因.而c-Jun活化区结合蛋白1(c-jun-activation-domain binding protein,Jab1)是新近发现的一种多功能蛋白,其在头颈肿瘤中的表达有助于了解肿瘤的发生、发展和预后,对肿瘤的治疗提供生物学依据.本文就Jab1与头颈肿瘤的关系做一综述.

Effect of Yanggan Jiedu Sanjie formula on human hepatocellular carcinoma Bel-7402 cells

OBJECTIVE: To observe the effect of Yanggan Jiedu Sanjie(YGJDSJ) formula on human hepatocellular carcinoma Bel-7402 cells.METHODS: Bel-7402 cells were treated with YGJDSJ. Cell proliferation was detected by cell counting kit-8 assay. Cell apoptosis was identified by Hoechst 33258 staining and flow cytometric analysis. Cell cycle distribution was quantified by flow cytometric analysis. Caspase activities were measured by commercial kit. Cell senescence was detected by senescence-associated β-galactosidase(SA-β-gal)staining. Protein expression and phosphorylation were identified by Western blot. Protein expression was knocked-down by siRNA.RESULTS: YGJDSJ inhibited proliferation of Bel-7402 cells in a dose-and time-dependent manner.YGJDSJ induced apoptosis and activated caspase-3, 8, and 9 in Bel-7402 cells. YGJDSJ-induced apoptosis was completely abrogated by a pan caspase inhibitor, Z-VAD-FMK. YGJDSJ also induced cell senescence, up-regulated cyclin-dependent kinase inhibitor 1 a(CDKN1 a) and CDKN2 a expression and down-regulated retinoblastoma protein(RB) phosphorylation in Bel-7402 cells. Specific knockdown of CDKN1 a and CDKN2 a significantly reduced YGJDSJ-induce cell senescence in Bel-7402 cells.CONCLUSION: YGJDSJ inhibited cell proliferation,induced caspase-dependent apoptosis and CDKN1 a/CDKN2 a-RB signalling mediated cell senescence in Bel-7402 cells. Our findings suggest that YGJDSJ might be potential for hepatocellular carcinoma treatment.