核因子κB抑制蛋白α在膀胱癌细胞系的表达与上皮-间质转化及体外侵袭能力负相关

目的探讨核因子-κB抑制蛋白α(IκBα)在不同膀胱癌细胞系的表达与上皮-间质转化(EMT)及肿瘤细胞体外侵袭能力的关系。方法 Western blot法比较人膀胱癌RT4细胞、5637细胞、235J细胞、J82细胞、T24细胞IκBα、上皮性钙黏素(E-cadherin)、神经钙黏素(N-cadherin)和波形蛋白(vimentin)的表达差异;通过TranswellTM实验比较5种细胞体外侵袭能力的差异;显微镜下观察并比较5种细胞形态学差异。结果 RT4细胞和5637细胞具有上皮细胞的形态学特征,253J细胞、J82细胞和T24细胞具有间质细胞的形态学特征。RT4细胞和5637细胞具有较高的E-cadherin表达水平,但不表达vimentin和N-cadherin。253J细胞、J82细胞和T24细胞E-cadherin表达部分(253J)或完全(J82、T24)缺失,但vimentin和N-cadherin表达水平较高。RT4细胞和5637细胞的体外侵袭能力明显弱于253J细胞、J82细胞和T24细胞。RT4细胞和5637细胞IκBα表达水平明显高于253J细胞、J82细胞和T24细胞。结论 IκBα在膀胱癌细胞的表达水平与EMT及体外侵袭能力负相关。     

下调长链非编码RNA PVT1表达对胰腺癌BxPC-3细胞凋亡、侵袭及转移的影响

目的研究下调长链非编码RNA PVT1的表达对胰腺癌细胞增殖、凋亡及侵袭转移能力的影响。方法体外转染PVT1干扰序列si PVT1-1和si PVT1-2降低胰腺癌细胞系Bx PC-3 PVT1表达,同时转染阴性对照si PVT1-NC作为对照组。CCK-8实验检测细胞增殖,流式细胞术检测细胞凋亡,细胞划痕实验和Transwell实验检测细胞侵袭转移;qRT-PCR检测E-cadherin、N-cadherin、β-catenin、vimentin和PVT1 mRNA表达;Western blot检测凋亡相关蛋白(Bax、Bcl-2、caspase-3)和上皮间质转化相关蛋白(E-cadherin、N-cadherin、β-catenin、vimentin)表达。结果下调胰腺癌细胞Bx PC-3 PVT1表达能明显抑制细胞增殖、促进细胞凋亡和减少细胞侵袭转移数目(P0.05);E-cadherin蛋白和分子水平升高,N-cadherin、β-catenin、vimentin蛋白和分子水平降低(P0.05);Bax和caspase-3蛋白水平升高,而Bcl-2蛋白水平降低(P0.05)。结论下调长链非编码RNA PVT1表达能抑制胰腺癌细胞增殖和侵袭转移能力,促进胰腺癌细胞凋亡,且能够逆转胰腺癌细胞上皮间质转化。     

HMGA2在胃癌细胞上皮-间充质转化中的作用

目的:探讨HMGA2在胃癌细胞上皮-间充质转化(EMT)中的作用及机制。方法:采用Western blot和RT-qPCR实验检测不同分化程度的人胃癌细胞株MKN45、MKN28和SGC7901以及人永生化胃黏膜上皮细胞株GES-1中HMGA2的表达水平;采用脂质体转染法将pcDNA3.0-HMGA2质粒转染至MKN28细胞中,将si-HMGA2干扰片段转染至MKN45细胞中,并采用Western blot和RT-qPCR实验检测转染效率;CCK-8实验检测HMGA2上调对MKN28细胞活力的影响以及HMGA2下调对MKN45细胞活力的影响;采用细胞迁移和侵袭实验检测HMGA2上调对MKN28细胞迁移和侵袭能力的影响;采用Western blot和RT-qPCR实验检测HMGA2过表达对MKN28细胞EMT相关标志蛋白上皮型钙黏蛋白(E-cadherin)、神经型钙黏蛋白(N-cadherin)和波形蛋白(vimentin)表达的影响以及敲减HMGA2表达对MKN45细胞E-cadherin、N-cadherin和vimentin表达的影响;采用RT-qPCR实验检测过表达HMGA2的MKN28细胞Wnt/β-catenin信号通路相关分子表达的变化。结果:HMGA2在不同分化程度的胃癌细胞中的表达水平是不同的(P0.05)。上调MKN28细胞HMGA2的表达水平能够抑制细胞活力(P0.05);而在MKN45细胞中下调HMGA2的表达水平能够增强细胞活力(P0.05)。上调MKN28细胞HMGA2的表达水平能够促进细胞的迁移和侵袭能力(P0.05),且E-cadherin表达降低,N-cadherin和vimentin表达升高(P0.05);敲减HMGA2在MKN45细胞的表达水平使E-cadherin表达升高,而N-cadherin和vimentin表达降低(P0.05)。上调MKN28细胞中HMGA2的表达水平,细胞内Wnt/β-catenin通路的β-catenin及其下游分子c-Myc和cyclin D1的mRNA表达水平显著增加(P0.05)。结论:HMGA2与胃癌细胞迁移和侵袭能力密切相关,并且能够通过激活细胞内Wnt/β-catenin通路,促进胃癌细胞EMT。     

Livin通过Akt信号途径促进胃癌SGC7901细胞的上皮细胞间质转换

目的探讨胃癌SGC7901细胞中Livin基因的表达对细胞上皮细胞间质转换(EMT)的影响。方法用Livin基因的shRNA慢病毒感染胃癌SGC7901细胞,筛选稳定沉默的细胞株,Transwell检测细胞的侵袭能力,细胞划痕实验检测细胞迁移能力,Western blot检测E-cadherin和vimentin表达,同时检测Akt信号通路的激活状态。结果沉默Livin基因后,胃癌SGC7901细胞侵袭迁移能力明显降低(P0.05),E-cadherin明显上调,vimentin则明显下调(P0.05),同时明显抑制Akt信号通路信号的激活(P0.05)。结论 Livin能够通过激活Akt信号通路从而诱导SGC7901细胞发生EMT,从而促进肿瘤细胞体外侵袭及迁移能力。     

X线电离辐射诱导人鼻咽癌CNE-2细胞发生上皮-间充质转化及其潜在机制

目的:探讨X线电离辐射诱导鼻咽癌CNE-2细胞发生上皮-间充质转化(epithelial-mesenchymal transition,EMT)及其可能的信号通路。方法:分别采用0 Gy、2 Gy、4 Gy和8 Gy的X线照射鼻咽癌CNE-2细胞,通过倒置显微镜观察照射24 h后细胞形态的改变;应用细胞划痕实验和Transwell实验观察细胞迁移和侵袭能力的变化;分别采用real-time PCR和Western blot法检测EMT相关蛋白E-钙黏蛋白(E-cadherin)、N-钙黏蛋白(N-cadherin)和波形蛋白(vimentin)mRNA及蛋白水平的变化,并采用Western blot法检测Akt和p-Akt蛋白水平的变化。结果:经X线照射后鼻咽癌CNE-2细胞呈典型的"鹅卵石"样或纺锤形,且伸出伪足,细胞间隙增大,细胞的侵袭和迁移能力增强(P0.01);real-time PCR和Western blot法检测结果显示,与未照射组相比,各照射组细胞中E-cadherin mRNA和蛋白的表达水平均显著下调(P0.01),而N-cadherin和vimentin mRNA和蛋白的表达水平明显上调(P0.05);PI3K/Akt信号通路中p-Akt蛋白的水平显著升高(P0.01),而Akt的表达无明显变化。结论:X线电离辐射能够诱导鼻咽癌CNE-2细胞发生EMT,其机制可能与PI3K/Akt信号通路的激活有关。     

Sox5促进胰腺癌细胞迁移侵袭和上皮间质化

目的:探讨Sox5对胰腺癌细胞迁移侵袭和上皮间质化的影响。方法:人正常胰腺细胞HPDE6-C7(HPDE6-C7组)、胰腺癌细胞PANC-1(PANC-1组)和AsPC-1(AsPC-1组)正常培养至对数生长期,采用qRT-PCR法和Western blot法分别检测各组细胞中Sox5mRNA和蛋白水平。将shSox5、shControl、pcDNA 3.1-Sox5和载体pcDNA 3.1以脂质体法转染胰腺癌细胞PANC-1,分别标记为shSox5组、shControl组、pcDNA 3.1-Sox5组和Scrambled组,采用qRT-PCR法检测各组细胞中Sox5、E-cadherin、N-cadherin、Vimetin、Snail和Twist1的mRNA表达;Western blot检测各组细胞中Sox5、E-cadherin、N-cadherin、Vimetin、Snail和Twist1的蛋白表达;Transwell法检测各组细胞的迁移和侵袭。结果:与HPDE6-C7组相比,PANC-1组和AsPC-1组中Sox5mRNA和蛋白水平均升高(P0.01);与shControl组比较,shSox5组Sox5、N-cadherin、Vimetin、Snail和Twist1的mRNA和蛋白以及细胞迁移和侵袭水平均显著降低(P0.01),E-cadherin mRNA和蛋白水平均显著升高(P0.01);与Scrambled组比较,pcDNA-3.1-Sox5组Sox5、N-cadherin、Vimetin、Snail和Twist1的mRNA和蛋白以及细胞迁移和侵袭水平均显著升高(P0.01),E-cadherin mRNA和蛋白水平均显著降低(P0.01)。结论:Sox5可促进胰腺癌细胞迁移、侵袭和EMT,将为胰腺癌的靶点治疗提供新靶标。     

Gli2基因沉默逆转肝癌细胞系SMMC-7721的上皮间质转化

目的探讨胶质瘤相关癌基因同源蛋白2(Gli2)对肝癌细胞系SMMC-7721上皮间质转化(EMT)和侵袭能力的影响及机制。方法合成shRNA-Gli2、shRNA-NC病毒载体,实验设shRNA-Gli2组、shRNA-NC组和空白组,转染SMMC-7721细胞。用Transwell小室和细胞黏附实验观察细胞侵袭及黏附能力;用qRT-PCR和Western blot检测细胞间Gli2、E-cadherin、N-cadherin及vimentin基因和蛋白的表达。结果在不同肝癌细胞系中,随着肝癌细胞系侵袭能力的增强,Gli2的表达逐渐增高,shRNA-Gli2组与对照组相比侵袭能力降低,同种黏附能力增加,异种黏附能力降低(P0.05)。shRNA-Gli2组与对照组相比,E-cadherin表达明显增高而N-cadherin和vimentin表达明显降低(P0.05)。结论沉默Gli2的表达能够促进肝癌细胞SMMC-7721 EMT的反转,并降低其侵袭能力,机制可能与E-cadherin的上调和N-cadherin、vimentin的下调有关。     

IMP3 基因沉默介导Notch 信号通路对结直肠癌上皮间质转化及血管生成的影响

目的:探究胰岛素样生长因子ⅡmRNA结合蛋白3(IMP3)基因沉默介导Notch信号通路对结直肠癌上皮间质转化(EMT)及血管生成的调控机制。方法:收集我院73例结直肠癌患者肿瘤切除术后癌组织及癌旁组织。免疫组化检测结直肠癌组织及癌旁组织中IMP3蛋白表达。将人结肠癌细胞系SW620细胞进行IMP3沉默或Notch通路抑制处理,设置阴性对照。Western blot检测处理后的细胞中Notch1、Hes1、Vimentin、E-cadherin、N-cadherin、VEGF、TNF-α和TGF-β蛋白表达。MTT比色法检测各组细胞活力。Transwell实验测定各组细胞侵袭能力。结果:免疫组化实验发现IMP3在癌组织中高表达。细胞实验表明IMP3沉默可下调Notch通路相关蛋白Notch1及Hes1表达。与阴性对照组相比,沉默IMP3或抑制Notch通路后,SW620细胞活力、转移能力、EMT管生成明显受到抑制(P0.05)。细胞经沉默IMP3联合抑制Notch通路处理,对上述指标的抑制效果较单独处理(沉默IMP3或抑制Notch通路)更加显著(P0.05)。结论:IMP3基因沉默能够抑制Notch通路活化进而抑制结直肠癌EMT及血管生成。     

子宫颈鳞状细胞癌中GDF-15与EMT相关蛋白的表达及相关性

目的检测子宫颈鳞状细胞癌组织中GDF-15及上皮-间质转化(epithelial-mesenchymal transition, EMT)相关蛋白E-cadherin、N-cadherin、vimentin的表达,探讨GDF-15在子宫颈鳞状细胞癌发生、侵袭中的生物学作用。方法采用免疫组化EliVision两步法检测85例子宫颈鳞状细胞癌组织及其配对癌旁子宫颈组织中GDF-15、E-cadherin、N-cadherin、vimentin的表达,分析GDF-15表达与子宫颈鳞状细胞癌临床病理特征的关系及GDF-15与EMT相关蛋白表达的相关性。结果与癌旁子宫颈组织相比,子宫颈鳞状细胞癌组织中GDF-15、N-cadherin和vimentin表达上调,E-cadherin表达下调,差异有统计学意义(P均0.05)。子宫颈鳞状细胞癌组织中GDF-15表达与N-cadherin和vimentin表达呈正相关(r_s=0.422,r_s=0.374),与E-cadherin表达呈负相关(r_s=-0.305)。结论 GDF-15与EMT相关蛋白在子宫颈鳞状细胞癌组织中异常表达,过表达GDF-15在子宫颈癌的发生、侵袭中发挥重要作用,可能与诱导子宫颈癌EMT有关。     

纺锤菌素抑制胃癌细胞的侵袭和转移

目的探讨纺锤菌素(netropsin)对胃癌细胞侵袭和转移能力的影响及其分子机制。方法用Transwell检测胃癌细胞侵袭和转移能力,用Western blot检测EMT相关标志物E-cadherin和vimentin表达,用免疫荧光检测β-catenin的细胞定位,验证netropsin作用前后Wnt/β-catenin信号通路活性。结果 Netropsin浓度25μmol/L时对MKN28细胞增殖有抑制作用,netropsin可以降低上皮标志物E-cadherin的表达,上调间质标志物vimentin的表达;netropsin可以通过抑制胃癌细胞的EMT,降低胃癌细胞侵袭和转移能力(P0.05),同时可阻止β-catenin进入细胞核。结论 Netropsin可以通过与HMGA2竞争结合转录因子结合位点抑制Wnt/β-catenin信号通路,降低胃癌细胞EMT的发生,从而抑制胃癌细胞侵袭能力。     

Pain and Effusion and Quadriceps Activation and Strength

Context:

Quadriceps dysfunction is a common consequence of knee joint injury and disease, yet its causes remain elusive.

Objective:

To determine the effects of pain on quadriceps strength and activation and to learn if simultaneous pain and knee joint effusion affect the magnitude of quadriceps dysfunction.

Design:

Crossover study.

Setting:

University research laboratory.

Patients or Other Participants:

Fourteen (8 men, 6 women; age = 23.6 ± 4.8 years, height = 170.3 ± 9.16 cm, mass = 72.9 ± 11.84 kg) healthy volunteers.

Intervention(s):

All participants were tested under 4 randomized conditions: normal knee, effused knee, painful knee, and effused and painful knee.

Main Outcome Measure(s):

Quadriceps strength (Nm/kg) and activation (central activation ratio) were assessed after each condition was induced.

Results:

Quadriceps strength and activation were highest under the normal knee condition and differed from the 3 experimental knee conditions (P < .05). No differences were noted among the 3 experimental knee conditions for either variable (P > .05).

Conclusions:

Both pain and effusion led to quadriceps dysfunction, but the interaction of the 2 stimuli did not increase the magnitude of the strength or activation deficits. Therefore, pain and effusion can be considered equally potent in eliciting quadriceps inhibition. Given that pain and effusion accompany numerous knee conditions, the prevalence of quadriceps dysfunction is likely high.Key Words: arthrogenic muscle inhibition, central activation failure, voluntary activation, muscles

Key Points

• Knee pain and effusion resulted in arthrogenic muscle inhibition and weakness of the quadriceps.
• The simultaneous presence of pain and effusion did not increase the magnitude of quadriceps dysfunction.
• To reduce arthrogenic muscle inhibition and improve muscle strength, clinicians should employ interventions that target removing both pain and effusion.

Quadriceps weakness is a common consequence of traumatic knee joint injury^1,2 and chronic degenerative knee joint conditions.^3,4 Arthrogenic muscle inhibition (AMI), a neurologic decline in muscle activation, results in quadriceps weakness and hinders rehabilitation by preventing gains in strength.⁵ The inability to reverse AMI and restore muscle function can lead to decreased physical abilities,⁶ biomechanical deficits,⁷ and possibly reinjury.⁵ Furthermore, researchers^8,9 have suggested that quadriceps weakness resulting from AMI may place patients at risk for developing osteoarthritis in the knee. In light of the substantial influence of quadriceps AMI on these clinically relevant outcomes, we need to improve our understanding of the factors that contribute to this neurologic decline in muscle activity so efforts to target and reverse it can be implemented and gains in strength can be achieved more easily.Joint injury and disease are accompanied by numerous sequelae (ie, pain, swelling, tissue damage, inflammation), so ascertaining which one ultimately leads to neurologic muscle dysfunction is difficult. Whereas a joint effusion can result in AMI,^10–12 the effects of pain are less understood despite many clinicians attributing AMI to pain. Using techniques that introduce knee pain without accompanying injury may provide insights into the role of pain in eliciting AMI.The degree of knee joint damage may play a role in the quantity of AMI that manifests. Hurley et al^13,14 demonstrated that quadriceps AMI, measured using an interpolated-twitch technique, was greater in patients with extensive traumatic knee injury (eg, fractured tibial plateau, ruptured medial collateral ligament, and medial meniscectomy) than patients with isolated joint trauma (ie, isolated anterior cruciate ligament [ACL] rupture). Similarly, patients with more knee joint symptoms (ie, greater number of symptoms and increased severity of symptoms) may present with greater magnitudes of quadriceps inhibition. Recently, investigators¹⁵ have suggested that patients with more pain display less quadriceps strength, supporting this tenet. Given that effusion and pain often present simultaneously with joint injuries and diseases, such as ACL injury and osteoarthritis, examining both the isolated and cumulative effects of these sequelae appears warranted to determine if they influence the magnitude of muscle inhibition.Experimental joint-effusion and pain models are safe and effective experimental methods that allow for the isolated examination of their effects on muscle function. The effusion model, whereby sterile saline is injected directly into the knee joint capsule,⁷ produces a clinically relevant magnitude of the joint effusion that may be present with traumatic injury. Effusion is thought to activate group II afferents responding to stretch or pressure,^16–18 which in turn may facilitate group Ib interneurons and result in quadriceps AMI.⁵ The pain model involves injecting hypertonic saline into the infrapatellar fat pad to produce anteromedial knee pain similar to that described in patients with patellofemoral pain syndrome.¹⁹ Pain is considered to initiate AMI through activation of group III and IV afferents that act as nocioceptors to signal damage or potential damage to joint structures.^16–18 The firing of these afferents then may lead to facilitation of group Ib interneurons, the flexion reflex, or the gamma loop, ultimately resulting in quadriceps inhibition.²⁰ Thus, these models allow us to create symptoms that are associated with knee injury and have the added benefit of providing a way to examine their effects in isolation.Therefore, the purpose of our study was to determine the effects of pain on quadriceps strength and activation and to learn if simultaneous pain and knee joint effusion would affect the magnitude of quadriceps dysfunction. We hypothesized that pain alone would result in quadriceps inhibition and that the magnitude of inhibition would be greater when effusion and pain were present simultaneously.     

即早基因c-fos与脑血管病及学习记忆

即早基因c-fos是广泛存在于原核细胞和真核细胞的高度保守基因.在正常情况下,c-fos基因参与细胞生长、分化、信息传递、学习和记忆等生理过程,而在病理情况下c-fos基因表达及调控变化与多种疾病的发生和发展有关.C-fos在中枢神经系统的某些部位可有基础水平的表达,但表达很低,当受到如脑缺血、脑出血、痫性发作、应激等刺激后,其在数十分钟内做出反应,在对外界刺激-转录耦联的信忠传递过程中起着核内第三信使的重要作用.     

Opportunities and challenges in the prevention and control of cancer and other chronic diseases: children's diet and nutrition and weight and physical activity

OBJECTIVE: The purpose of this article is to review the role of behavioral research in disease prevention and control, with a particular emphasis on lifestyle- and behavior-related cancer and chronic disease risk factors--specifically, relationships among diet and nutrition and weight and physical activity with adult cancer, and tracking developmental origins of these health-promoting and health-compromising behaviors from childhood into adulthood. METHOD: After reviewing the background of the field of cancer prevention and control and establishing plausibility for the role of child health behavior in adult cancer risk, studies selected from the pediatric published literature are reviewed. Articles were retrieved, selected, and summarized to illustrate that results from separate but related fields of study are combinable to yield insights into the prevention and control of cancer and other chronic diseases in adulthood through the conduct of nonintervention and intervention research with children in clinical, public health, and other contexts. RESULTS: As illustrated by the evidence presented in this review, there are numerous reasons (biological, psychological, and social), opportunities (school and community, health care, and family settings), and approaches (nonintervention and intervention) to understand and impact behavior change in children's diet and nutrition and weight and physical activity. CONCLUSIONS: Further development and evaluation of behavioral science intervention protocols conducted with children are necessary to understand the efficacy of these approaches and their public health impact on proximal and distal cancer, cancer-related, and chronic disease outcomes before diffusion. It is clear that more attention should be paid to early life and early developmental phases in cancer prevention.