乳腺癌细胞药耐中P38MAPK活性与凋亡关系的实验研究

Objective  

The aim of this study was to investigate the relationship between p38MAPK activity and apoptosis during the drug resistance of breast carcinoma cell lines.     

p38MAPK信号转导通路及其与细胞凋亡的关系

丝裂原活化蛋白激酶(Mitogen-activatedproteinkinases,MAPKs)是广泛表达的丝氨酸/酪氨酸激酶,在哺乳动物细胞多种信号转导通路中起重要作用,MAPKs有3个主要家族:ERKs,JNKs和p38MAPKs。p38信号通路是MAPK通路的一重要分支,它在炎症、细胞应激、凋亡、细胞周期和生长等多种生理和病理过程中起重要作用。4种已知的p38异构体包括p38α、p38β、p38γ和p38δ。多年来已发现p38MAPK通路可以由应激包括高渗、热休克、放射线和其他应激反应活化。因此,p38MAPK通路参与了多种刺激引起的信号级联反应,表明它在引起多种细胞反应中起重要作用,并且,p38在细胞凋亡中也显示调节效应。     

脑胶质瘤细胞化疗耐药中p38MAPK信号通路的作用

探讨p38MAPK信号通路在脑胶质瘤细胞化疗耐药中的作用及相关机制。 方法 在 前期建立U251/TMZ胶质瘤耐药细胞株的基础上,用特异性阻断剂SB203580阻断耐药细胞株中 p38MAPK信号通路,替莫唑胺作用下检测耐药株的细胞活性变化,同时检测MDR1、TopoⅡ、BCL-2 等耐药相关基因的蛋白表达变化。 结果 阻断通路后替莫唑胺作用下细胞的抑制率明显低于未阻 断组,两组之间比较差异有统计学意义（P＜0.05）,阻断后耐药细胞中BCL-2、MDR1的表达明 显升高,TopoⅡ的表达明显降低,与未阻断的耐药细胞相比较差异有统计学意义（P＜0.05）。结 论 U251/TMZ胶质瘤耐药细胞中p38MAPK信号通路被阻断后细胞的耐药性增强,其机制可能与耐药 株中耐药相关基因BCL-2、TopoⅡ、MDR1的表达变化有关。     

缺氧对人肝癌HepG2细胞凋亡及p38MAPK通路的影响

目的:探讨缺氧对人肝癌HepG2细胞凋亡及p38MAPK通路的影响。方法:用三气培养箱培养肝癌细胞HepG2,建立缺氧细胞模型,CCK-8 法检测HepG2细胞的增殖率,流式细胞术检测细胞凋亡率,Real-time PCR分析p38MAPK mＲNA的表达,Western blot法检测p38MAPK及p-p38MAPK蛋白的表达变化。结果:缺氧可抑制人肝癌HepG2细胞的增殖,抑制细胞凋亡（P<0.05）;缺氧处理人肝癌HepG2细胞后,p38MAPK mＲNA的表达量下调(P<0.05);Western blot结果显示缺氧可下调p38MAPK、p-p38MAPK蛋白的表达（P<0.05）。结论:缺氧通过抑制p38MAPK通路抑制人肝癌HepG2细胞凋亡。     

p38MAPK在介导TNF-α诱导大鼠胶质瘤细胞凋亡中的作用

目的 :探讨p38MAPK在介导TNF α所致大鼠胶质瘤细胞C6凋亡中的作用。方法 :应用MTT法检测TNF α处理的C6细胞的增殖活性 ,采用透射电镜和流式细胞仪观察凋亡的发生 ,应用SABC法和Westernblot检测p38MAPK的表达 ,应用流式细胞仪及SABC法观察 p38MAPK特异性抑制剂SB2 0 2 1 90对TNF α诱导C6细胞凋亡的影响。结果 :TNF α(2× 1 0 5U/L)对C6细胞增殖的抑制率为 43 .75 % ,透射电镜下可见典型的凋亡细胞 ,流式细胞仪检测凋亡率为 37.5 % ,SABC法和Westernblot显示P38MAPK表达阳性 ;加入SB2 0 2 1 90后 ,其凋亡率为 7.0 % ,未见P38MAPK表达。结论 :TNF α能诱导C6细胞凋亡和 p38MAPK表达 ,p38MAPK的活化促进了C6细胞凋亡的发生     

p38MAPK 在结肠癌细胞凋亡中的作用及与COX-2 的关系

 目的 探讨结肠癌细胞p38MAPK介导celecoxib（COX-2选择性抑制剂）抗肿瘤的作用及与COX-2的关系。方法 用MTT法检测celecoxib对人结肠癌HT-29细胞生长的作用，用Western blot法测定各组细胞COX-2和Phosph—p38MAPK蛋白表达量，采用流式细胞术检测celecoxib和SB203580（p38MAPK特异性抑制剂）作用后HT-29细胞凋亡和细胞周期分布。结果 p38MAPK和COX-2蛋白表达量与对照组（0．23±0.12）（0.95±0．14）相比，celecoxib可使p38MAPK蛋白表达水平明显升高（0．62±0．11），而使COX-2蛋白表达水平降低（0、44±0．11）；SB203580使p38MAPK（0.12±0．05）及COX-2蛋白（0、23±0．13）表达水平均降低；SB203580和celecoxib共同作用后，p38MAPK表达量介于celecoxib和SB203580作用之间（0．43±0．12），COX-2表达量下降最为显著（0．15±0．10））。celecoxib和eeleeoxib＋SB203580均可显著诱导HT-29细胞凋亡（P〈0．01和P〈0．05），与对照纽（4．31％）相比，其凋亡率分别为40．95％、26．24％。结论 在HT29细胞中，celecoxib可通过活化p38MAPK而诱导结肠癌细胞凋亡，p38MAPK是COX-2的上游激酶，COX-2的表达水平受p38MAPK调控，并且COX-2可能对p38MAPK有负反馈调节作用。celecoxib是通过COX-2及其以外的p38MAPK通路诱导肿瘤细胞凋亡而发挥抗肿瘤作用的。     

p38 MAPK在喹乙醇诱导HepG2细胞凋亡中的作用

目的:研究p38 MAPK信号通路在喹乙醇诱导的HepG2细胞凋亡中的作用。方法:分别用不同浓度(0、200、400、800μg/ml)的喹乙醇染毒HepG2细胞24 h和800μg/ml喹乙醇染毒HepG2细胞不同时间(0、0.5、1、2、4、6、12、24 h)后,采用Westernblot法检测细胞内磷酸化p38蛋白和p38总蛋白的表达情况,以p38 MAPK磷酸化水平反映p38 MAPK信号通路的活性。分别采用0、10、20μmol/L的p38 MAPK特异性抑制剂SB203580预处理HepG2细胞1 h后,再用800μg/ml喹乙醇染毒24 h,采用Annexin VFITC/PI法检测细胞凋亡。结果:随着喹乙醇染毒浓度和时间的增加,HepG2细胞的p38磷酸化蛋白表达量逐步增加,其中800μg/ml喹乙醇染毒细胞24 h的实验组与对照组相比,p38磷酸化蛋白的表达量明显上调(P0.01)。10、20μmol/L的SB203580对喹乙醇诱导细胞凋亡有促进作用,细胞的凋亡率分别为35.4%±2.83%、40.2%±3.98%,较喹乙醇对照组(23.1%±3.59%)明显升高(P0.05)。结论:喹乙醇能激活p38 MAPK信号通路,且p38 MAPK信号通路的激活参与抑制喹乙醇介导的HepG2细胞凋亡的过程。     

p38 MAPK信号通路与肿瘤的关系

丝裂原活化蛋白激酶（mitogen-activated protein kinase,MAPK）级联是细胞内广泛存在的丝／苏氨酸蛋白激酶超家族,是将细胞质的信号传递至细胞核并引起细胞核发生变化的重要物质。目前在人类已鉴定了4条MAPK途径：细胞外信号调节蛋白激酶（extra cellular signal—regulated protein kinase,ERK）途径,C—Jun基末端激酶（c—Jun N—terminal kinase,JNK）／应激活化蛋白（stress—activated protein kinase,SAPK）途径,ERKS／大丝裂素活化蛋白激酶1（big MAP MAP kinase,BMK1）途径和p38MAPK（p38 mitogen activated protein kinases,p38MAPK）传导途径。p38信号途径是MAPK家族中的重要组成部分,     

p38MAPK对卵巢癌顺铂耐药作用及机制的探讨

目的:研究p38MAPK在卵巢上皮癌顺铂化疗耐药中的作用,并探讨其作用机制.方法:蛋白质印迹法检测顺铂对卵巢癌中p38MAPK的激活情况 ;MTT法检测p38MAPK抑制剂SB203580处理后及p38 shRNA干扰后细胞顺铂耐药指数的变化 ;实时定量PCR技术检测SB203580处理后及p38 shRNA干扰后,耐药蛋白ERCC1、MDR、LRP、GST-π及凋亡蛋白Caspase-3、Survivin等mRNA的表达变化.结果:在一定时间浓度梯度下,顺铂可诱导卵巢癌顺铂敏感株COC1及耐药株COC1/DDP细胞内p38MAPK的激活,但耐药株的激活程度弱于敏感株 ;p38MAPK抑制剂SB203580及p38 shRNA干扰可增加卵巢癌细胞株的耐药指数(t=4.610,P=0.041 ;t=11.621,P=0.000) ;SB203580及p38 shRNA干扰后Survivin mRNA(t=5.152,P=0.007 ;t=6.008,P=0.004)、ERCC1 mRNA(t=13.742,P=0.005;t=11.621,P=0.000)及LRPmRNA(t=8.173,P=0.001 ;t=16.815,P=0.000)的表达明显上调.结论:p38MAPK受抑制可能导致卵巢上皮性癌顺铂耐药的产生,其机制可能是通过上调Survivin、ERCC1及LRP的mRNA表达来实现.     

白血病细胞多药耐药与细胞凋亡的关系

目的 :探讨白血病细胞多药耐药 (MDR)与细胞凋亡的关系。方法 :在体外用化疗药物阿霉素 (ADM)诱导白血病细胞株 K5 6 2 MDR的产生 ,用 As2 O3诱导细胞的凋亡 ,采用流式细胞仪检测细胞表面 P糖蛋白 (P- gp)的表达 ;荧光定量 PCR检测 MDR1 m RNA;通过流式细胞仪检测Anexin- V判断凋亡细胞数量的多少 ;观察 MDR与细胞凋亡的关系。结果 :5 μm ol/ L 的 ADM能诱导 K5 6 2细胞 MDR的产生 ,随着作用时间的延长 ,P- gp/ MDR1 m RNA的表达逐渐升高 ;P- gp/MDR1 m RNA的表达与细胞凋亡呈负相关 (r=0 .6 8,P<0 .0 1 ) ;在 As2 O3作用下 ,细胞凋亡增加的同时 ,P- gp的表达下调。结论 :抗癌药物能诱导白血病细胞 MDR的产生 ,细胞的耐药性与凋亡抑制相关 ,诱导细胞的凋亡能减低白血病细胞的 MDR。     

RELATIONSHIP BETWEEN EXPRESSIONS OF P38 PROTEIN IN HUMAN BREAST CARCINOMA AND LYMPH NODES METASTASIS

Objective： To detect the change of p38 protein expression and investigate the relationship of p38 and lymph nodes metastasis in human breast carcinomas. Methods： Sixty breast cancer cases were checked by S-P immunohistochemistry technique and 30 breast cancer cases were examined by Western Blot. Results： Immunohistochemical results showed that p38 protein was observed in breast cancer and normal cytoplasm. P-p38 was positive in nucleus in breast cancer. P38 protein expressed positively in 29 out of 38 patients who had lymph nodes metastasis （positive rate 76.3%） and in 9 out of 22 patients who had no lymph nodes metastasis （positive rate 40.9%）. There was a significant difference between these two groups （P〈0.01）. The positive rate of p-p38 in patients who had lymph nodes metastasis was 68.4%, and the positive rate in patients who had no metastasis was 36.4%, and there was a significant difference between these two groups （P〈0.05）. The result of western blot showed that the protein contents of p38 and p-p38 in patients with metastasis was higher than those in patients without metastasis （P〈0.05）. P38 and p-p38 protein expressions had relation with clinical pathological grades in breast cancer, higher in grade Ⅲ than in grade Ⅰ, Ⅱ （P〈0.05）, while had no relation with patients＇ age and tumor size （P〉0.05）. Conclusion： p38 and p-p38 protein expressions had relationship with lymph nodes metastasis and the levels of p38 and p-p38 protein expression in groups with lymph nodes metastasis were higher than in groups without lymph nodes metastasis. P38 and p-p38 protein expressions had relationship with clinical grades and had no relationship with patients＇ age and tumor size.     

乙型肝炎病毒X蛋白对肝癌细胞MKK3,p38MAPK表达的影响

目的：观察乙型肝炎病毒X蛋白对肝癌细胞中丝裂原活化蛋白激酶（MKK3）及其下游分子p38丝裂酶原活化的蛋白激酶（p38MAPK）的表达的影响,探讨相关的信号转导机制,及其对肝癌细胞生物学行为的影响。方法：分别将质粒pCDNA3.1及pCDNA3.1-HBx重组质粒经脂质体介导转染人肝癌细胞株HepG2,G418筛选培养,并用反转录PCR和Western blot鉴定,获得表达X蛋白的稳定细胞株HepG2-HBx和阴性对照细胞株HepG2-pCDNA3.1,以HepG2细胞株作空白对照。通过RT-PCR和Western blot检测上述三种细胞株中MKK3,p38MAPK在mRNA水平和蛋白水平的表达变化,并用细胞免疫荧光法检查磷酸化p38MAPK蛋白在细胞浆及细胞核中的变化;通过MTT实验检测三种细胞株的增殖情况。采用SPSS 12软件进行统计学分析。结果：MKK3在mRNA和总蛋白水平的表达在HepG2-HBx中均高于其他两组,其他两组无明显差异;p38MAPK在mRNA和总蛋白水平三组无明显差异,而其蛋白磷酸化水平和在核蛋白中的表达在HepG2-HBx中较其他两组升高;HepG2-HBx较其他两组细胞有更强的增殖能力。结论：HBx可以通过上调肝癌细胞中MKK3的表达,促进p38MAPK磷酸化和入核,从而进一步激活下游分子发挥生物活性。p38MAPK通路在HBx促进肝癌细胞的增殖中发挥重要作用。可能是导致HBV相关性肝癌与非HBV相关性肝癌临床特点及肿瘤生物学差异的机制之一。     

p38丝裂原活化蛋白激酶信号转导对肿瘤细胞凋亡的调控

p38丝裂原活化蛋白激酶(p38MAPK)信号通路是丝裂原活化蛋白激酶(MAPK)家族的一条重要途径,可被多种细胞外刺激而激活,近年来研究发现在细胞凋亡中发挥重要作用.p38MAPK可通过活化半胱天冬氨酸蛋白酶(caspase)家族成员、调节Bcl-2家族成员的活性、活化p53、参与Fas-FasL通路等多种途径介导肿瘤细胞的凋亡过程.     

乙型肝炎病毒X蛋白对肝癌细胞MKK3,p38MAPK表达的影响

目的:观察乙型肝炎病毒X蛋白对肝癌细胞中丝裂原活化蛋白激酶(MKK3)及其下游分子p38丝裂酶原活化的蛋白激酶(p38MAPK)的表达的影响,探讨相关的信号转导机制,及其对肝癌细胞生物学行为的影响。方法:分别将质粒pCDNA3.1及pCDNA3.1-HBx重组质粒经脂质体介导转染人肝癌细胞株HepG2,G418筛选培养,并用反转录PCR和Western blot鉴定,获得表达X蛋白的稳定细胞株HepG2-HBx和阴性对照细胞株HepG2-pCDNA3.1,以HepG2细胞株作空白对照。通过RT-PCR和Western blot检测上述三种细胞株中MKK3,p38MAPK在mRNA水平和蛋白水平的表达变化,并用细胞免疫荧光法检查磷酸化p38MAPK蛋白在细胞浆及细胞核中的变化;通过MTT实验检测三种细胞株的增殖情况。采用SPSS 12软件进行统计学分析。结果:MKK3在mRNA和总蛋白水平的表达在HepG2-HBx中均高于其他两组,其他两组无明显差异;p38MAPK在mRNA和总蛋白水平三组无明显差异,而其蛋白磷酸化水平和在核蛋白中的表达在HepG2-HBx中较其他两组升高;HepG2-HBx较其他两组细胞有更强的增殖能力。结论:HBx可以通过上调肝癌细胞中MKK3的表达,促进p38MAPK磷酸化和入核,从而进一步激活下游分子发挥生物活性。p38MAPK通路在HBx促进肝癌细胞的增殖中发挥重要作用。可能是导致HBV相关性肝癌与非HBV相关性肝癌临床特点及肿瘤生物学差异的机制之一。     

p38delta/MAPK13 as a diagnostic marker for cholangiocarcinoma and its involvement in cell motility and invasion

Cholangiocarcinoma (CC) and hepatocellularcarcinoma (HCC) are two main forms of liver malignancies, which exhibit differences in drug response and prognosis. Immunohistotochemical staining for cytokeratin markers has been used to some success in the differential diagnosis of CC from HCC. However, there remains a need for additional markers for increased sensitivity and specificity of diagnosis. In this study, we have identified a p38 MAP kinase, p38δ (also known as MAPK13 or SAPK4) as a protein that is upregulated in CC relative to HCC and to normal biliary tract tissues. We performed microarray gene expression profiling on 17 cases of CC, 12 cases of adjacent normal liver tissue, and three case of normal bile duct tissue. p38δ was upregulated in 16 out of 17 cases of CC relative to normal tissue. We subsequently performed immunohistochemical staining of p38δ in 54 cases of CC and 54 cases of HCC. p38δ staining distinguished CC from HCC with a sensitivity of 92.6% and a specificity of 90.7%. To explore the possible functional significance of p38δ expression in CC, we examined the effects of overexpression and knockdown of p38δ expression in human CC cell lines. Our results indicate that p38δ is important for motility and invasion of CC cells, suggesting that p38δ may play an important role in CC metastasis. In summary, p38δ may serve as a novel diagnostic marker for CC and may also serve as a new target for molecular based therapy of this disease.     

p38 MAPK inhibits breast cancer metastasis through regulation of stromal expansion

p38 MAPK signaling controls cell growth, proliferation and the cell cycle under stress conditions. However, the function of p38 activation in tumor metastasis is still not well understood. We report that p38 activation in breast cancer cells inhibits tumor metastasis but does not substantially modulate primary tumor growth. Stable p38 knockdown in breast cancer cells suppressed NF‐κB p65 activation, inhibiting miR‐365 expression and resulting in increased IL‐6 secretion. The inhibitory effect of p38 signaling on metastasis was mediated by suppression of mesenchymal stem cell (MSC) migration to the primary tumor and sites of metastasis, where MSCs can differentiate into cancer‐associated fibroblasts to promote tumor metastasis. The migration of MSCs to these sites relies on CXCR4‐SDF1 signaling in the tumor microenvironment. Analysis of human primary and metastatic breast cancer tumors showed that p38 activation was inversely associated with IL‐6 and vimentin expression. This study suggests that combination analysis of p38 MAPK and IL‐6 signaling in patients with breast cancer may improve prognosis and treatment of metastatic breast cancer.     

A role for p38 MAPK in head and neck cancer cell growth and tumor-induced angiogenesis and lymphangiogenesis

We have recently gained a remarkable understanding of the mutational landscape of head and neck squamous cell carcinoma (HNSCC). However, the nature of the dysregulated signaling networks contributing to HNSCC progression is still poorly defined. Here, we have focused on the role of the family of mitogen activated kinases (MAPKs), extracellular regulated kinase (ERK), c-Jun terminal kinase (JNK) and p38 MAPK in HNSCC. Immunohistochemical analysis of a large collection of human HNSCC tissues revealed that the levels of the phosphorylated active form of ERK1/2 and JNK were elevated in less than 33% and 16% of the cases, respectively. Strikingly, however, high levels of active phospho-p38 were observed in most (79%) of hundreds of tissues analyzed. We explored the biological role of p38 in HNSCC cell lines using three independent approaches: treatment with a specific p38 inhibitor, SB203580; a retro-inhibition strategy consisting in the use of SB203580 combined with the expression of an inhibitor-insensitive mutant form of p38α; and short-hairpin RNAs (shRNAs) targeting p38α. We found that specific blockade of p38 signaling significantly inhibited the proliferation of HNSCC cells both in vitro and in vivo. Indeed, we observed that p38 inhibition in HNSCC cancer cells reduces cancer growth in tumor xenografts and a remarkable decrease in intratumoral blood and lymphatic vessels. We conclude that p38α functions as a positive regulator of HNSCC in the context of the tumor microenvironment, controlling cancer cell growth as well as tumor-induced angiogenesis and lymphangiogenesis.