MBD1 RNA干扰对胰腺癌细胞VIMENTIN、GRP78表达影响的实验研究

目的：观察下调甲基化CpG结合域蛋白1（MBD1）表达后对胰腺癌细胞甲基化相关基因VIMENTIN、GRP78表达的影响,探讨MBD1介导的甲基化调控网络在胰腺癌发生、发展中的重要作用。方法：人工设计合成针对MBD1基因的小分子干扰RNA,构建MBD1-siRNA重组质粒,脂质体法转染人胰腺癌细胞株BxPC-3,RT-PCR和Western印迹法检测转染前后MBD1、VIMENTIN和GRP78 mRNA与蛋白表达的变化。结果：MBD1-siRNA重组质粒成功转染胰腺癌细胞系BxPC-3,并筛选得到稳定表达的细胞株。转染后胰腺癌BxPC-3细胞株MBD1、VIMENTIN和GRP78的mRNA与蛋白表达水平均明显降低。结论：MBD1下调可使胰腺癌细胞VIMENTIN和GRP78表达下降：MBD1可能通过调控甲基化相关基因的表达,在胰腺癌的发生、发展过程中起重要的作用。     

微管不稳定蛋白Stathmin对胰腺癌侵袭转移的影响及其相关甲基化调控

目的 探讨微管不稳定蛋白Stathmin在胰腺癌侵袭转移中的作用及其与甲基化调控的关系.方法 免疫组化检测40例胰腺癌组织和15例正常胰腺组织中MBDI和Stathmin的蛋白表达,分析其与胰腺癌临床病理特征的关系.利用RNA干扰技术将Stathmin-siRNA转染BxPC-3细胞,将细胞分为Stathmir-siRNA组和空质粒对照组.Transwell小室侵袭实验测定细胞迁移侵袭能力的变化,将两组细胞接种裸鼠,观察肿瘤转移的情况.去甲基化药物5-Aza-2’-dC( AZA)处理人胰腺癌细胞BxPC-3,定量RT-PCR和Western blot检测AZA处理前后Stathmin mRNA与蛋白的表达变化.结果 免疫组化显示,MBDI和Stathmin蛋白在40例胰腺癌标本中分别有28例(70.0％)和24例(60.0％)阳性表达,明显高于正常胰腺组织(P＜0.05).MBDI和Stathmin蛋白的阳性表达呈正相关(r=0.356,P=0.037,MBDI的表达与淋巴结转移有关(P=0.023),Stathmin的表达则与临床分期、淋巴结转移有关(P=0.002,0.001).Transwell小室侵袭实验显示,与对照组相比,Stathmin-siRNA组细胞的侵袭能力明显减弱(P＜0.05);动物实验显示,Stathmin-siRNA组细胞接种于裸鼠后,肝转移发生率明显低于空质粒对照组(P＜0.05);AZA处理BxPC-3细胞后,Stathmin mRNA 和蛋白表达明显下降.结论 微管不稳定蛋白Stathmin在胰腺癌中存在高表达,并与胰腺癌的侵袭转移特性有关;Stathmin的表达受到DNA甲基化调控,去甲基化可降低胰腺癌中Stathmin的表达.     

MBD1甲基化调控胰腺癌BxPC-3细胞株mdr1转录及其表达的研究

目的 观察MBD1通过对mdr1转录区域结合位点甲基化影响,在转录水平间接调控胰腺癌mdr1基因表达.方法 应用RNA干扰技术对人胰腺癌细胞株BxPC-3中MBD1基因进行抑制;应用定量荧光聚合酶链式反应(FQ-PCR)技术、MSP(甲基化专用聚合酶链式反应)方法分别检测转染前后细胞株中的mdr1 mRNA的表达差异和转录区域结合位点甲基化变化.结果 成功构建并转染MBDI siRNAs至人原位胰腺腺癌细胞BxPC-3(BxPC-3)细胞中,证实MBDI mRNA水平明显下调(下调幅度为93.19%).MBD1下调后,mdr1 DNA转录区域(-110GC和-50GC)甲基化分别上调(上调幅度分别为181.98%和409.57%);mdr1 mRNA表达明显下调(下调幅度为97.79%).结论 MBD1可通过对mdr1转录区域结合位点甲基化的影响,在转录水平间接调控胰腺癌mdr1基因表达.     

MBD1甲基化调控胰腺癌BxPC-3细胞株mdr1转录及其表达的研究

目的 观察MBD1通过对mdr1转录区域结合位点甲基化影响,在转录水平间接调控胰腺癌mdr1基因表达.方法 应用RNA干扰技术对人胰腺癌细胞株BxPC-3中MBD1基因进行抑制;应用定量荧光聚合酶链式反应(FQ-PCR)技术、MSP(甲基化专用聚合酶链式反应)方法分别检测转染前后细胞株中的mdr1 mRNA的表达差异和转录区域结合位点甲基化变化.结果 成功构建并转染MBDI siRNAs至人原位胰腺腺癌细胞BxPC-3(BxPC-3)细胞中,证实MBDI mRNA水平明显下调(下调幅度为93.19%).MBD1下调后,mdr1 DNA转录区域(-110GC和-50GC)甲基化分别上调(上调幅度分别为181.98%和409.57%);mdr1 mRNA表达明显下调(下调幅度为97.79%).结论 MBD1可通过对mdr1转录区域结合位点甲基化的影响,在转录水平间接调控胰腺癌mdr1基因表达.     

MBD1甲基化调控胰腺癌BxPC-3细胞株mdr1转录及其表达的研究

目的 观察MBD1通过对mdr1转录区域结合位点甲基化影响,在转录水平间接调控胰腺癌mdr1基因表达.方法 应用RNA干扰技术对人胰腺癌细胞株BxPC-3中MBD1基因进行抑制;应用定量荧光聚合酶链式反应(FQ-PCR)技术、MSP(甲基化专用聚合酶链式反应)方法分别检测转染前后细胞株中的mdr1 mRNA的表达差异和转录区域结合位点甲基化变化.结果 成功构建并转染MBDI siRNAs至人原位胰腺腺癌细胞BxPC-3(BxPC-3)细胞中,证实MBDI mRNA水平明显下调(下调幅度为93.19%).MBD1下调后,mdr1 DNA转录区域(-110GC和-50GC)甲基化分别上调(上调幅度分别为181.98%和409.57%);mdr1 mRNA表达明显下调(下调幅度为97.79%).结论 MBD1可通过对mdr1转录区域结合位点甲基化的影响,在转录水平间接调控胰腺癌mdr1基因表达.     

MBD1 RNA干扰对胰腺癌细胞株BxPC-3生长影响的实验研究

目的 观察阻断MBD1表达后对胰腺癌细胞生长增殖的影响,探讨MBD1在胰腺癌发生发展中的作用.方法 采用RNA干扰技术,构建MBD1-siRNA重组质粒,脂质体介导转染人胰腺癌细胞株BxPC-3,RT-PCR和Western印迹检测转染前后MBD1 mRNA与蛋白的表达变化,MTT法检测转染前后BxPC-3细胞的生长曲线,将细胞接种于裸鼠,观察转染前后胰腺癌细胞体内移植瘤的生长情况.结果 转染siRNA-MBD1质粒后胰腺癌细胞株BxPC-3 MBD1的mRNA与蛋白表达水平明显降低.MTT法检测细胞的生长曲线,发现转染组较转染空质粒组和未转染组生长明显缓慢(P<0.01);体内实验显示,将转染前后的细胞接种于裸鼠,转染组移植瘤生长速度明显较其他两组减慢(P<0.01),RT-PCR检测移植瘤MBD1mRNA表达的变化,转染组中未能测到明显的MBD1表达.而转染组中CDH1、Rb等抑癌基因mRNA的表达明显高于转染空质粒组和未转染组.结论 通过RNA干扰技术,可在转录和翻译水平降低MBD1在胰腺癌细胞株BxPC-3中的表达,并能抑制肿瘤细胞的生长,但其作用机制尚不清楚,MBD1介导的转录抑制作用可能在胰腺癌的发生发展过程中起到重要的作用.     

甲基化CpG结合域蛋白1在胰腺癌组织中的表达和意义

目的：检测甲基化CpG结合域蛋白I（MBD1）蛋白在胰腺癌组织中的表达，并探讨其临床意义。方法：应用S-P免疫组织化学法检测38例胰腺癌、17例胰腺癌旁组织、8例胰腺良性肿瘤、3例慢性胰腺炎和6例正常胰腺组织中MBD1蛋白的表达。结果：MBD1在胰腺癌组织、正常胰腺组织、胰腺良性肿瘤、胰腺癌旁组织中的表达阳性率分别是76．32％（29/38）、16．67％（1／6）、25．0％（2／8）、29．41％（5／17），3例慢性胰腺炎标本中未见表达；胰腺癌阳性表达率明显高于正常胰腺、慢性炎症、良性肿瘤和癌旁对照组织（P〈0．05）。MBD1表达水平的高低与病人的性别、年龄、肿瘤部位、肿瘤大小、分化程度和TNM分期无显著性差异（P〉0．05）；而与淋巴结转移密切相关，有淋巴结转移者胰腺癌组织MBD1的表达阳性率为92．31％（24／26），高于无淋巴结转移者的41．67％（5／12）（P〈0．01）。结论：胰腺癌中MBD1呈高水平表达，并与胰腺癌的高转移侵袭活性有关，其机制可能与MBD1介导抑制多个甲基化相关抑癌基因的表达有关。MBD1的转录调控机制有待进一步研究。     

微小RNA-125b靶向调控乳腺癌易感基因相关蛋白1调节胰腺癌细胞增殖及侵袭

目的探究微小RNA(miR)-125b可否通过调节乳腺癌易感基因相关蛋白1(BAP1)调节胰腺癌细胞的发生与发展进程, 探讨其在胰腺癌中的作用。方法采用实时定量聚合酶链反应和蛋白印迹检测2018年1月至2020年12月21例在我科接受手术患者的胰腺癌组织、癌旁组织和胰腺癌细胞系中miR-125b和其靶蛋白的表达水平。通过细胞克隆实验、流式细胞凋亡检测技术、划痕实验以及细胞侵袭实验检测转染前后胰腺癌细胞增殖、凋亡、细胞迁移和侵袭能力, 组间比较采用t检验。结果 miR-125b在胰腺癌组织中的表达显著上调(2.48±0.46比0.68±0.15, t=13.991, P<0.01)。过表达miR-125b组的BAP1的表达明显低于对照组(465.57±11.28比933.80±15.46, t=5.894, P<0.01)。过表达miR-125b组Panc-1和BxPC-3A细胞的增殖、迁移和侵袭能力明显高于对照组(214.56±8.45比78.43±5.15, t=3.482, P<0.01)。过表达BAP1组Panc-1和BxPC-3A细胞的增殖、迁移和侵袭能力明显...     

长链非编码RNA HOST2对胰腺癌细胞增殖迁移和侵袭的影响

目的:探讨长链非编码RNA(lncRNA)HOST2对胰腺癌细胞增殖、迁移和侵袭的影响及机制。方法:qRT-PCR检测正常胰腺上皮细胞系HPDE6-C7及胰腺癌细胞系Panc-1、AsPC-1、BxPC-3、HPAC中lncRNAHOST2表达水平。将Panc-1细胞分别转染siRNA-HOST2(si-HOST2组)和阴性对照序列(阴性对照组)后,用MTT法测定细胞增殖,细胞划痕和Transwell实验测定细胞迁移和侵袭,Westernblot测定上皮-间质转化(EMT)相关蛋白vimentin、Snail、Twist的表达。以无转染的Panc-1细胞为空白对照组。结果:与正常胰腺上皮细胞HPDE6-C7相比,lncRNAHOST2在各胰腺癌细胞系中的表达均明显上调(均P0.05)。与空白对照组比较,si-HOST2组细胞增殖、迁移和侵袭能力均明显减弱,vimentin、Twist1、Snail蛋白相对表达量均明显下调(均P0.05),而阴性对照组上述指标均无明显变化(均P0.05)。结论:lncRNAHOST2在胰腺癌细胞中高表达,且与胰腺癌增殖、迁移和侵袭密切相关,其机制可能与调节EMT相关蛋白的表达有关。     

以白细胞介素4-受体为靶标的胰腺癌靶向治疗研究

目的 检测白细胞介素4受体(IL-4R)在胰腺癌组织及人胰腺癌细胞株中的表达,观察以抗白细胞介素-4受体单抗(MAIL4R)为载体构建的免疫毒素MAIL4R-CTX对胰腺癌细胞的靶向杀伤作用.方法 应用免疫组织化学检测IL-4R在26例胰腺癌组织、15例胰腺正常组织中的表达;免疫细胞化学染色检测IL-4R在人胰腺癌PANC-1、BxPC-3细胞和人肺腺癌H1299细胞中的表达;采用噻唑蓝(MTT)法观察MAIL4R、眼镜蛇毒细胞毒素(CTX)、免疫毒素MAIL4R-CTX对体外培养PANC-1,BxPC-3细胞和H1299细胞生长的影响.结果 IL-4R在26例胰腺癌组织中均呈不同程度的阳性表达,而15例胰腺正常组织中仅1例呈弱阳性表达,余均为阴性表达;人胰腺癌PANC-1,BxPC-3细胞均表达IL-4R,H1299细胞不表达IL-4R;CTX对PANC-1,BxPC-3和H1299细胞均有明显抑制作用,但对3株细胞的抑制率差异无统计学意义(P＞0.05);MAIL4R对PANC-1、BxPC-3和H1299细胞均无明显抑制作用;MAIL4R-CTX对过表达IL-4R的BxPC-3和PANC-1细胞的生长具有显著的抑制作用,并且为剂量依赖性,而对低表达IL-4R的H1299细胞不敏感,在浓度为18.75 mg/L,作用4h时PANC-1和BxPC-3细胞分别有86.4%和95.2%被杀伤,H1299细胞仅死亡26.8%(P＜0.01).结论 IL-4R过表达于胰腺癌组织和胰腺癌细胞株,而低表达于正常胰腺组织中,免疫毒素MAIL4R-CTX在体外对过表达IL-4R的细胞株PANC-1、BxPC-3有靶向性杀伤作用.     

Glial fibrillary acidic protein and neurofilament protein in medulloblastoma

Medulloblastoma is the most common primitive neuroectodermal tumor (PNET) with the potential to differentiate along glial or neuronal lines. Thirty cases of medulloblastoma were tested by the peroxidase-antiperoxidase (PAP) method with anti-GFAP serum (DAKO) and by the avidin-biotin peroxidase complex (ABC) method with 68kd subunit of anti-NF antibody. All the cases were classified into three subtypes based on these immunohistochemical findings and were analyzed in relation to clinico-pathological features. Fifteen of thirty medulloblastomas contained GFAP positive cells, seventeen showed cells reacting to NF. The reactions for both proteins were present in eight medulloblastomas (PNET-BD, bipotential differentiation). Seventeen medulloblastomas reacted to only one protein (PNET-MD, monopotential differentiation). No reaction for either was found in five cases (PNET-NOS, not otherwise specified). The two year survival rate was 12.5% for PNET-BD compared to 49.2% for PNET-MD and 53.3% for PNET-NOS. Nine variables, i.e. age, tumor stage, metastatic stage, operation, radiotherapy, chemotherapy, histology, GFAP and NF, were analyzed using Cox's proportional hazard model. This revealed that the significant factors were tumor stage (p = 0.0002), GFAP (p = 0.0008) and operation (p less than 0.05). In conclusion, GFAP is the most important histological factor for prognosis and medulloblastoma without glial differentiation has a much better prognosis than one with glial differentiation.     

Sperm protein carbonylation

The cryopreservation of sperm is a well established technique that plays an essential role in dissemination of elite germplasm of livestock. Despite having numerous advantages, the cryopreservation induces certain stresses on sperm including structural and functional damages leading to impaired sperm quality and fertility, which might be associated with production of reactive oxygen species (ROS). In addition, the ROS upon reacting with sperm lipids, DNA and proteins may lead to a cascade of sperm damages. The sperm membrane contains a rich amount of polyunsaturated fatty acids, which increases their susceptibility to oxidative stress induced damages, leading to formation of secondary products. These secondary products result in oxidation of sperm proteins via carbonylation. The carbonylation could lead to disturbances in specific proteins that are involved in capacitation. The present review deals with sperm protein carbonylation.     

Angiogenic protein therapy

Therapeutic angiogenesis, in the form of growth factor protein administration or gene therapy, has emerged as a new method of treatment for patients with severe, inoperable coronary artery disease. Improved myocardial perfusion and function after the administration of angiogenic growth factors has been demonstrated in animal models of chronic myocardial ischemia. A recent clinical study reported beneficial long-term effects of therapeutic angiogenesis using FGF-2 protein in terms of freedom from angina and myocardial perfusion on nuclear imaging and suggested that protein angiogenic therapy has the potential to extend treatment options to patients who are not optimal candidates for conventional methods of myocardial revascularization. The ultimate role that angiogenesis will play in the treatment of ischemic heart disease will, however, be determined from adequately powered, randomized, double-blind, placebo-controlled trials. It is likely that endogenous antiangiogenic influences, intrinsic lack of response of patients with severe endothelial dysfunction, and other limitations will have to be overcome before angiogenesis becomes standard therapy for the treatment of coronary artery disease.     

Plasma protein derivatives

Plasma protein derivatives produced from human plasma include albumin, blood coagulation factors, immuno globulins, haptoglobin, and c1-inactivator and have been widely used clinically. However, the HIV-tainted blood scandal in which HIV was transmitted to many Japanese patients through blood coagulation factors, must be remembered. The safety of blood products has increased since then in response to that event. Because blood products are provided by volunteer donors, there is a risk of contamination by unknown pathogens and they must be used appropriately. In addition, blood products including plasma derivatives are defined as "special biological products" and regulated by the new Medicine Act. All physicians who prescribe plasma derivatives should understand not only their clinical use but also social expectations and legal regulations.