The NEDD4-1 E3 ubiquitin ligase: A potential molecular target for bortezomib sensitivity in multiple myeloma

E3 ubiquitin ligases primarily determine the substrate specificity of the ubiquitin-proteasome system and play an essential role in the resistance to bortezomib in multiple myeloma (MM). Neural precursor cell-expressed developmentally downregulated gene 4-1 (NEDD4-1, also known as NEDD4) is a founding member of the NEDD4 family of E3 ligases and is involved in the proliferation, migration, invasion and drug sensitivity of cancer cells. In the present study, we investigated the role of NEDD4-1 in MM cells and explored its underlying mechanism. Clinically, low NEDD4-1 expression has been linked to poor prognosis in patients with MM. Functionally, NEDD4-1 knockdown (KD) resulted in bortezomib resistance in MM cells in vitro and in vivo. The overexpression (OE) of NEDD4-1, but not an enzyme-dead NEDD4-1-C867S mutant, had the opposite effect. Furthermore, the overexpression of NEDD4-1 in NEDD4-1 KD cells resensitized the cells to bortezomib in an add-back rescue experiment. Mechanistically, pAkt-Ser473 levels and Akt signaling were elevated and decreased by NEDD4-1 KD and OE, respectively. NEDD4-1 ubiquitinated Akt and targeted pAkt-Ser473 for proteasomal degradation. More importantly, the NEDD4-1 KD-induced upregulation of Akt expression sensitized MM cells to growth inhibition after treatment with an Akt inhibitor. Collectively, our results suggest that high NEDD4-1 levels may be a potential new therapeutic target in MM.     

旋覆代赭汤对反流性食管炎大鼠模型TLR4/NF-κB的影响

目的观察旋覆代赭汤对反流性食管炎(RE)模型大鼠食管黏膜与脂多糖(LPS)、Toll样受体4(TLR4)、核因子κB(NF-κB)表达的影响。方法将60只雄性Wistar大鼠按随机数字表法分为正常对照组、模型组、旋覆代赭汤组(简称中药组,9.89 g/kg)、西药(奥美拉唑+莫沙比利,2.58 mg/kg)组,每组15只。除正常对照组外大鼠采用“4.2 mm幽门夹+2/3胃底结扎术”制备酸碱混合反流RE大鼠模型。术后第7天予相应药物干预,持续干预14天。利用光学显微镜观察大鼠食管下段黏膜组织形态学变化;应用ELISA法检测定外周血中LPS含量;采用Western Blot法与RT-PCR法检测食管黏膜组织中TLR4、NF-κB蛋白和基因表达。结果与正常对照组比较,模型组大鼠食管黏膜镜下损伤最为严重,食管黏膜呈炎性改变,可见急慢性炎细胞浸润,病理积分和外周血中LPS含量升高(P<0.05),食管组织中TLR4、NF-κB蛋白和基因表达升高(P<0.05)。与模型组比较,中药组、西药组病理积分和外周血中LPS含量降低(P<0.05),食管组织中TLR4、NF-κB蛋白和基因表达亦明显降低(P<0.05)。结论旋覆代赭汤能够减轻RE模型大鼠食管黏膜的损伤,抑制TLR4、NF-κB的表达,促进食管黏膜损伤的恢复。     

B7-H4及Fas、FasL与宫颈癌免疫逃逸机制的关系

目的:检测免疫共刺激分子B7-H4及Fas、FasL在不同宫颈组织中的表达，研究三者的异常表达与宫颈癌免疫逃逸机制的关系。方法:选择陕西省肿瘤医院病理科2014-2018年的石蜡包埋标本162例，采用免疫组织化学方法检测20例正常宫颈、30例宫颈上皮内瘤变(CIN)和112例I期-IV期宫颈癌组织中B7-H4及Fas、FasL的表达水平。结果:B7-H4在正常宫颈组、CIN组、宫颈癌组的阳性表达率分别为0、20.0%、47.32%，两两相比，具有显著性差异（P<0.05）。在112例宫颈癌病例中FIGO临床分期I期至IV期各期别宫颈癌组织B7-H4的阳表达率分别为16.67%、43.18%、70.83%、85.71%，各组间相比差异具有统计学意义。正常对照组Fas的阳性表达率是85.00％，CIN组43.33％，宫颈癌组41.96％，正常组与CIN、正常组与宫颈癌组相比差异均具有统计学意义（P<0.05），CIN组与宫颈癌组相比，无明显差异（P>0.05）。FasL的阳性表达率在正常组为20.00%，CIN组为50.00%，宫颈癌组为56.25%，正常组与CIN、宫颈癌组比较，差异具有统计学意义(P<0.05)，CIN组与宫颈癌组比较无显著差异;B7-H4阳性宫颈癌组Fas阳性表达率28.30%明显较B7-H4阴性宫颈癌组Fas阳性表达率54.24%低，差异具有统计学意义（P<0.05）；而B7-H4阳性宫颈癌组FasL阳性表达率79.25%明显高于B7-H4阴性宫颈癌组FasL阳性表达率35.59%，差异具有统计学意义（P<0.05）。结论:负性免疫共刺激分子B7-H4和Fas、FasL凋亡蛋白在宫颈癌的发生、进展中起到了重要作用，其协同作用可能为宫颈癌细胞逃逸机体免疫的机制之一。     

PFKFB4对胃癌细胞侵袭和迁移能力的影响及其作用

目的 探讨激酶PFKFB4是否参与调控胃癌细胞侵袭和迁移并对其作用机理进行初步研究。方法 使用免疫共沉淀检测与PFKFB4有相互作用的SRC家族蛋白,通过转录组测序寻找下游调控基因,利用Western blot和qRT-PCR验证下游基因与磷酸化SRC蛋白的关系,并通过Transwell方法检测PFKFB4相关通路对胃癌细胞迁移和侵袭能力的影响。结果 PFKFB4能够与SRC-2相互作用,但PFKFB4不影响SRC-2的表达,而是磷酸化SRC-2第698位的丝氨酸;SRC-2 Ser698磷酸化后,其下游调控基因LKB1的mRNA和蛋白的表达水平都受到抑制,同时胃癌细胞的迁移和侵袭能力增强。结论 PFKFB4通过磷酸化SRC-2负调控抑癌因子LKB1的表达增强胃癌细胞的迁移和侵袭能力。     

维生素D联合糠酸莫米松乳膏治疗婴幼儿中重度湿疹的临床分析

目的:分析维生素D联合糠酸莫米松乳膏治疗婴幼儿中重度湿疹的临床疗效并探究维生素D对患儿免疫功能的影响。方法:104例中重度湿疹婴幼儿随机分为对照组和治疗组各52例,对照组用0.1%糠酸莫米松乳膏治疗,治疗组在对照组基础上予维生素D制剂阿法骨化醇滴剂治疗。分析治疗后2组患儿治疗总有效率,同时检测患儿治疗前及治疗4周后血清25-(OH)D3、干扰素-γ(IFN-γ)、白细胞介素(IL-2)、IL-4、IL-13水平。结果:治疗组总有效率为92.31%,优于对照组(76.92%),差异有统计学意义(P<0.05)。治疗组治疗后血清IFN-γ、IL-2水平较治疗前上升,并明显高于对照组,血清IL-4、IL-13水平较治疗前下降,并明显低于对照组(P<0.05)。结论:维生素D能调节中重度湿疹婴幼儿免疫功能,因此维生素D联合糠酸莫米松乳膏能提高中重度湿疹婴幼儿治疗疗效,值得在临床上应用。     

Exendin-4 attenuates pain-induced cognitive impairment by alleviating hippocampal neuroinflammation in a rat model of spinal nerve ligation

Glucagon-like peptide-1 receptor has anti-apoptotic,anti-inflammatory,and neuroprotective effects.It is now recognized that the occurrence and development of chronic pain are strongly associated with anti-inflammatory responses;however,it is not clear whether glucagon-like peptide-1 receptor regulates chronic pain via anti-inflammatory mechanisms.We explored the effects of glucagon-like peptide-1 receptor on nociception,cognition,and neuroinflammation in chronic pain.A rat model of chronic pain was established using left L5 spinal nerve ligation.The glucagon-like peptide-1 receptor agonist exendin-4 was intrathecally injected into rats from 10 to 21 days after spinal nerve ligation.Electrophysiological examinations showed that,after treatment with exendin-4,paw withdrawal frequency of the left limb was significantly reduced,and pain was relieved.In addition,in the Morris water maze test,escape latency increased and the time to reach the platform decreased following exendin-4 treatment.Immunohistochemical staining and western blot assays revealed an increase in the numbers of activated microglia and astrocytes in the dentate gyrus of rat hippocampus,as well as an increase in the expression of tumor necrosis factor alpha,interleukin 1 beta,and interleukin 6.All of these effects could be reversed by exendin-4 treatment.These findings suggest that exendin-4 can alleviate pain-induced neuroinflammatory responses and promote the recovery of cognitive function via the glucagon-like peptide-1 receptor pathway.All experimental procedures and protocols were approved by the Experimental Animal Ethics Committee of Renmin Hospital of Wuhan University of China(approval No.WDRM 20171214)on September 22,2017.     

Consensus summary report for CEPI/BC March 12–13, 2020 meeting: Assessment of risk of disease enhancement with COVID-19 vaccines

A novel coronavirus (CoV), Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in late 2019 in Wuhan, China and has since spread as a global pandemic. Safe and effective vaccines are thus urgently needed to reduce the significant morbidity and mortality of Coronavirus Disease 2019 (COVID-19) disease and ease the major economic impact. There has been an unprecedented rapid response by vaccine developers with now over one hundred vaccine candidates in development and at least six having reached clinical trials. However, a major challenge during rapid development is to avoid safety issues both by thoughtful vaccine design and by thorough evaluation in a timely manner. A syndrome of “disease enhancement” has been reported in the past for a few viral vaccines where those immunized suffered increased severity or death when they later encountered the virus or were found to have an increased frequency of infection. Animal models allowed scientists to determine the underlying mechanism for the former in the case of Respiratory syncytial virus (RSV) vaccine and have been utilized to design and screen new RSV vaccine candidates. Because some Middle East respiratory syndrome (MERS) and SARS-CoV-1 vaccines have shown evidence of disease enhancement in some animal models, this is a particular concern for SARS-CoV-2 vaccines. To address this challenge, the Coalition for Epidemic Preparedness Innovations (CEPI) and the Brighton Collaboration (BC) Safety Platform for Emergency vACcines (SPEAC) convened a scientific working meeting on March 12 and 13, 2020 of experts in the field of vaccine immunology and coronaviruses to consider what vaccine designs could reduce safety concerns and how animal models and immunological assessments in early clinical trials can help to assess the risk. This report summarizes the evidence presented and provides considerations for safety assessment of COVID-19 vaccine candidates in accelerated vaccine development.     

艾炷灸命门穴对衰老模型大鼠脑组织中AGEs、RAGE表达影响

目的:观察艾炷灸命门穴对D-半乳糖致衰老大鼠脑组织中AGEs及其受体RAGE表达的影响,探讨艾炷灸命门穴延缓衰老的作用机制。方法:雄性SD大鼠40只,随机分为空白组10只、模型制备组30只,空白组腹腔注射生理盐水,模型制备组进行腹腔注射D-半乳糖500 mg/kg,每日1次,连续60天,模型制备成功后随机选取20只分为模型对照组、命门穴治疗组,艾炷灸治疗4周。酶联免疫吸附测定法(Elisa)观察各组大鼠脑组织匀浆中AGES、RAGE表达水平,RT-PCR观察RAGE mRNA的表达水平。结果:模型对照组大鼠脑组织中AGES、RAGE及RAGE mRNA表达水平比空白组明显增加(P<0.01);命门穴治疗组脑组织中AGES、RAGE及RAGE mRNA表达水平明显低于模型对照组(P<0.01)。结论:艾炷灸命门穴可以延缓衰老,其机制可能是AGEs的水平下调减少了对蛋白的直接修饰及抑制AGEs与特异性配体RAGE结合而引发一系列的生物学效应而达到延缓衰老的目的。     

Functional beta-cells derived from umbilical cord blood mesenchymal stem cells for curing rats with streptozotocin-induced diabetes mellitus

INTRODUCTIONThis study aimed to investigate the therapeutic response to injected human umbilical cord blood mesenchymal stem cells (UCBMSCs) among albino rats with streptozotocin (STZ)-induced diabetes mellitus.METHODSControl group (GI; n = 25) rats were fed with standard rat diet. Rats with STZ-induced diabetes mellitus without (GII; n = 25) and with (GIII; n = 25) differentiated human UCBMSCs implantation were the test groups. Rats were sacrificed in Week 11 following implantation. Liver biopsies were sectioned and stained in order to highlight both the presence and function of impregnated cells in the liver tissue.RESULTSHaematoxylin and eosin-stained sections in GI and GII rats showed normal liver architecture while GIII rats showed presence of cell clusters inside the liver tissue and around the central veins. Cell clusters with blue cytoplasm were present in sections in GIII rats but absent in GI and GII rats, indicating the presence of injected differentiated human UCBMSCs. The anti-human insulin immunostaining of GIII rats showed clusters of cells within the liver parenchyma and around central veins, indicating that these cells were active and secreting insulin.CONCLUSIONUCBMSCs are proficient in differentiating into insulin-producing cells in vivo under specific conditions and, when transplanted into the liver of albino rats with STZ-induced diabetes mellitus, were able to secrete insulin and partially control the status of diabetes mellitus in rats.