Reinforcing B16F10/GPI-IL-21 vaccine efficacy against melanoma by injecting mice with shZEB1 plasmid or miR200c agomir

In this study, we hypothesized that the inhibition of epithelial to mesenchymal transition (EMT) program by knockdown of Zinc-finger E-box binding homeobox 1 (ZEB1) or administration of miR200c agomir would strengthen the B16F10 cells transfected with GPI-anchored IL-21 (B16F10/GPI-IL-21) vaccine efficacy in inhibiting the melanoma metastasis. Our findings from the current study indicated that, when compared with the mice immunized with the B16F10/GPI-IL-21 vaccine alone, the mice immunized with B16F10/GPI-IL-21 vaccine combined with injection of shZEB1 plasmid or miR200c agomir not only meaningfully inhibited EMT of melanoma, reduced the EMT characteristic molecular expression in tumor tissues, but also significantly decreased the Treg cells and TGF-β1, enhanced the cytotoxicities of NK cells and cytotoxic T lymphocytes and the IFN-γ level. Furthermore, the immunotherapeutic combination resulted in inhibiting the melanoma growth and lung metastasis. Our study demonstrated that using the B16F10/GPI-IL-21 vaccine in combination with the down-regulated ZEB1 or miR200c administration effectively elicited anti-tumor immunity and reduced melanoma metastasis by inhibiting the EMT program in the B16F10 melanoma-bearing mice.     

过氧化物酶体增殖物激活受体γ激动剂对二氧化硅致成纤维细胞纤维连接蛋白表达的影响（英文）

背景：过氧化物酶体增殖物激活受体γ激动剂对转化生长因子β1致矽肺肺间质纤维化作用的影响及机制尚不明确,罕见报道。目的：观察过氧化物酶体增殖物激活受体γ激动剂对转化生长因子β1致矽肺肺纤维化作用的影响。方法：200mg/LSiO2刺激SD大鼠肺泡巨噬细胞培养上清液作用于中国仓鼠肺成纤维细胞株（CHL）建立矽肺纤维化的体外细胞模型。RT-PCR检测过氧化物酶体增殖物激活受体γ配体15d-PGJ2及其激动剂曲格列酮和齐格列酮对转化生长因子β1诱导CHL的纤维连接蛋白mRNA表达的影响。利用Western印迹技术观察过氧化物酶体增殖物激活受体γ激动剂对转化生长因子β1诱导CHL的纤维连接蛋白表达的影响。结果与结论：①转化生长因子β1mRNA表达呈一定范围内的剂量（0~5μg/L）和时间（0~24h）依赖效应。②过氧化物酶体增殖物激活受体γ配体及激动剂降低了纤维连接蛋白mRNA和蛋白的表达。结果提示过氧化物酶体增殖物激活受体γ激动剂可以抑制转化生长因子β1诱导的SiO2致肺成纤维细胞纤维连接蛋白合成,具有抗SiO2所致肺间质纤维化的潜在作用。     

过氧化物酶体增殖物激活受体γ激动剂对二氧化硅致成纤维细胞纤维连接蛋白表达的影响

背景:过氧化物酶体增殖物激活受体γ激动剂对转化生长因子β1致矽肺肺间质纤维化作用的影响及机制尚不明确,罕见报道.目的:观察过氧化物酶体增殖物激活受体γ激动剂对转化生长因子β1致矽肺肺纤维化作用的影响.方法:200 mg/L SiO2刺激SD大鼠肺泡巨噬细胞培养上清液作用于中国仓鼠肺成纤维细胞株(CHL)建立矽肺纤维化的体外细胞模型.RT-PCR检测过氧化物酶体增殖物激活受体γ配体15d-PGJ2及其激动剂曲格列酮和齐格列酮对转化生长因子β1诱导CHL的纤维连接蛋白mRNA表达的影响.利用Western印迹技术观察过氧化物酶体增殖物激活受体γ激动剂对转化生长因子β1诱导CHL的纤维连接蛋白表达的影响.结果与结论:①转化生长因子β1 mRNA表达呈一定范围内的剂量(0～5 μg/L)和时间(0～24 h)依赖效应.②过氧化物酶体增殖物激活受体γ配体及激动剂降低了纤维连接蛋白mRNA和蛋白的表达.结果提示过氧化物酶体增殖物激活受体γ激动剂可以抑制转化生长因子β1诱导的SiO2致肺成纤维细胞纤维连接蛋白合成,具有抗SiO2所致肺间质纤维化的潜在作用.     

Distinct mechanisms of TGF-beta1-mediated epithelial-to-mesenchymal transition and metastasis during skin carcinogenesis

In the present study, we demonstrated that human skin cancers frequently overexpress TGF-beta1 but exhibit decreased expression of the TGF-beta type II receptor (TGF-(beta)RII). To understand how this combination affects cancer prognosis, we generated a transgenic mouse model that allowed inducible expression of TGF-beta(1) in keratinocytes expressing a dominant negative TGF-(beta)RII (Delta(beta)RII) in the epidermis. Without Delta(beta)RII expression, TGF-beta1 transgene induction in late-stage, chemically induced papillomas failed to inhibit tumor growth but increased metastasis and epithelial-to-mesenchymal transition (EMT), i.e., formation of spindle cell carcinomas. Interestingly, Delta(beta)RII expression abrogated TGF-beta1-mediated EMT and was accompanied by restoration of membrane-associated E-cadherin/catenin complex in TGF-beta1/Delta(beta)RII compound tumors. Furthermore, expression of molecules thought to mediate TGF-beta1-induced EMT was attenuated in TGF-beta1/Delta(beta)RII-transgenic tumors. However, TGF-beta1/Delta(beta)RII-transgenic tumors progressed to metastasis without losing expression of the membrane-associated E-cadherin/catenin complex and at a rate higher than those observed in nontransgenic, TGF-beta1-transgenic, or Delta(beta)RII-transgenic mice. Abrogation of Smad activation by Delta(beta)RII correlated with the blockade of EMT. However, Delta(beta)RII did not alter TGF-beta1-mediated expression of RhoA/Rac and MAPK, which contributed to increased metastasis. Our study provides evidence that TGF-beta1 induces EMT and invasion via distinct mechanisms. TGF-beta1-mediated EMT requires functional TGF-(beta)RII, whereas TGF-beta1-mediated tumor invasion cooperates with reduced TGF-(beta)RII signaling in tumor epithelia.     

胃癌患者组织中EMT相关蛋白、TGF-β1 mRNA相对表达水平与淋巴结转移的相关性分析

目的 观察胃癌患者组织中上皮间质转化(EMT)相关蛋白、转化生长因子(TGF)-β1 mRNA表达与淋巴结转移的相关性.方法 将该院2016年1月至2020年11月收治的51例胃癌合并淋巴结转移患者纳入淋巴结转移组,另将该院同期收治的51例胃癌未合并淋巴结转移患者纳入无淋巴结转移组,收集患者资料,并进行回顾性分析.采用...     

G9a interacts with Snail and is critical for Snail-mediated E-cadherin repression in human breast cancer

Breast cancers are highly heterogeneous but can be grouped into subtypes based on several criteria, including level of expression of certain markers. Claudin-low breast cancer (CLBC) is associated with early metastasis and resistance to chemotherapy, while gene profiling indicates it is characterized by the expression of markers of epithelial-mesenchymal transition (EMT) - a phenotypic conversion linked with metastasis. Although the epigenetic program controlling the phenotypic and cellular plasticity of EMT remains unclear, one contributor may be methylation of the E-cadherin promoter, resulting in decreased E-cadherin expression, a hallmark of EMT. Indeed, reduced E-cadherin often occurs in CLBC and may contribute to the early metastasis and poor patient survival associated with this disease. Here, we have determined that methylation of histone H3 on lysine 9 (H3K9me2) is critical for promoter DNA methylation of E-cadherin in three TGF-β-induced EMT model cell lines, as well as in CLBC cell lines. Further, Snail interacted with G9a, a major euchromatin methyltransferase responsible for H3K9me2, and recruited G9a and DNA methyltransferases to the E-cadherin promoter for DNA methylation. Knockdown of G9a restored E-cadherin expression by suppressing H3K9me2 and blocking DNA methylation. This resulted in inhibition of cell migration and invasion in vitro and suppression of tumor growth and lung colonization in in vivo models of CLBC metastasis. Our study not only reveals a critical mechanism underlying the epigenetic regulation of EMT but also paves a way for the development of new treatment strategies for CLBC.     

高糖诱导肾小管上皮细胞转化的作用

目的观察高糖诱导肾小管上皮的转化,以及转化生长因子13,（TGF-β1）和信号转导蛋白（Smad）受体激活锚定蛋白（SARA）的变化。方法建立高糖诱导肾小管上皮细胞（HKC）转化模型,高糖处理HKC0、12、24、48h后提取总蛋白,Westernblot法检测波形蛋白、钙黏附蛋白、TGF—β1、SARA和Smad2蛋白的表达。结果Westernblot法检测高糖处理HKC0、12、24、48h后,钙黏附蛋白的相对表达量分别为1．13±0．31、0．74±0．1g、0．63±0．18、0．32±0．12,各组之间两两比较差异均有统计学意义（P均〈0．05）;波形蛋白相对表达量分别为0．23±0．09、0．34±0．04、0．83±0．15、1．02±0．22,各组之间两两比较差异均有统计学意义（P均〈0．05）;TGF—B1蛋白的相对表达量分别为0．25±O．08、0．44±O．12、0．72±0．21、0．92±0．28,各组之间两两比较差异均有统计学意义（P均〈0．05）;SARA蛋白的相对表达量分别为0．83±0．21、0．54±0．13、0．42±0．09、0．35±0．12,各组之间两两比较差异均有统计学意义（P均〈0．05）;Smad2蛋白的相对表达量分别为1．14±0．22、0．82±0．15、0.61±0．17、0．30±0．13,各组之间两两比较差异均有统计学意义（P均〈0．05）。结论高糖可诱导HKC转化,TGF—β1通路的激活可能是其主要的作用机制,SARA蛋白的下调和继发的Smad2蛋白降解协同了TGF—β1通路的致纤维化作用。     

SIP1在TGF—β1诱导的人腹膜间皮细胞转分化的作用

【目的】阐明Smad作用蛋白1（Smad interacting proteinl,SIP1）与转化生长因子－β1（transforming growth factor－β1,TGF-β1）诱导的人腹膜间皮细胞（human peritoneal mesothelial cells）转分化（epithelial—mesenchymal transition,EMT）的关系,探讨TGF－β1可能通过调控SIP1引起腹膜间皮细胞EMT的机制。【方法】培养的人腹膜间皮细胞株（HMrSV5）随机分为对照组（TGF-β1刺激Oh）和TGF－β1刺激组,通过western blot及realtime PCR检测细胞中E－钙粘素（E－eadherin）、紧密连接蛋白（claudinl）、波形蛋白（vimentin）及纤维连接蛋白（fibronectin,FN）在不同时间点（12h,24h,48h,72h）的表达;并通过western blot及realtime PCR检测相应时间点细胞中SIP1的表达。【结果】5ng／ml TGF－β1刺激后,HMrsV5细胞E-cadherin、claudinl蛋白及mRNA表达水平呈时间依赖性降低（P〈0．01）;vimentin、FN蛋白及mRNA表达水平呈时间依赖性升高（P〈0．01）;SIP1蛋白及mRNA表达水平呈时间依赖性上调（P〈0．01）。【结论】TGF-β1可能通过上调HMrSV5细胞SIP1表达诱导HMrSV5细胞EMT及细胞外基质（extracellular matrix,ECM）沉积,将为进一步研究腹膜纤维化的分子机制提供新的靶点。     

过氧化物酶体增殖因子活化受体γ在大肠癌中的表达及意义

目的：分析过氧化物酶体增殖因子活化受体（PPAR-γ）的表达与大肠癌临床病理特征之间的关系,并探讨PPAR-γ对大肠癌细胞增殖活性的影响。方法：采用免疫组织化学法,检测56例带有癌旁正常黏膜的大肠癌组织中PPAR-γ与增殖细胞核抗原（PCNA）的表达。结果：PPAR-γ在大肠癌组织中的表达显著高于癌旁正常黏膜组织（P〈0.001）。PPAR-γ的表达与肿瘤分化程度、浸润深度、Dukes分期以及淋巴结转移有密切关系（P〈0.05）。PPAR-γ的表达程度与PCNA显著相关（P〈0.001）。结论：PPAR-γ的表达与大肠癌的分化程度、浸润深度和Dukes分期及淋巴结转移有关;PPAR-γ可促进大肠癌细胞的增殖。     

过氧化物酶体增生物激活受体γ的表达与肺癌生长机制研究

目的研究过氧化物酶体增生物激活受体γ( PPAR γ)经配体活化后抑制肺癌生长的机制.方法通过 RT-PCR和 Western blot检测肺癌细胞株上 PPAR γ的表达,并通过 MTT和细胞计数检测经 PPAR γ的配体作用后的细胞增殖情况,以 TUNEL检测细胞的凋亡情况.结果两种细胞株上均有 PPAR γ的表达; PPAR γ的配体作用后明显抑制细胞生长,且与时间和剂量有关;经配体活化的 PPAR γ能诱导细胞凋亡,使其增殖受抑.结论 PPAR γ在肺癌细胞上表达,经配体活化后能通过诱导凋亡而抑制肺癌细胞的生长,作为肺癌治疗的新靶点.     

The inhibitory effect of heat treatment against epithelial-mesenchymal transition (EMT) in human pancreatic adenocarcinoma cell lines

Epithelial-mesenchymal transition (EMT) plays a crucial role in cancer metastasis. In this study, we evaluated the effect of heat treatment on tumor growth factor-β1 (TGF-β1)-induced EMT in pancreatic cancer cells and tried to ascertain the mechanism related to any observed effects. Human pancreatic cancer cell lines (BxPC-3, PANC-1 and MIAPaCa-2) were stimulated by TGF-β1, and evaluated for morphological changes using immunofluorescence and EMT-related factors (i.e., E-cadherin, Vimentin, Snail or ZEB-1) using RT-PCR. To examine the effect of heat on EMT, the cancer cells were heat-treated at 43°C for 1 h then stimulated with TGF-β1. We then evaluated whether or not heat treatment changed the expression of EMT-related factors and cell migration and also whether Smad activation was inhibited in TGF-β signaling. After being treated with TGF-β1, pancreatic cancer cells resulted in EMT and cell migration was enhanced. Heat treatment inhibited TGF-β1-induced changes in morphology, inhibited the expression of EMT-related factors, and attenuated TGF-β1-induced migration in pancreatic cancer cells. Additionally, we observed that heat treatment blocked TGF-β1-induced phosphorylation of Smad2 in PANC-1 cells. Our results suggest that heat treatment can suppress TGF-β1-induced EMT and opens the possibility of a new therapeutic use of hyperthermia as a potential treatment for cancer metastasis.     

Pivotal role of cardiomyocyte TGF-β signaling in the murine pathological response to sustained pressure overload

The cardiac pathological response to sustained pressure overload involves myocyte hypertrophy and dysfunction along with interstitial changes such as fibrosis and reduced capillary density. These changes are orchestrated by mechanical forces and factors secreted between cells. One such secreted factor is TGF-β, which is generated by and interacts with multiple cell types. Here we have shown that TGF-β suppression in cardiomyocytes was required to protect against maladaptive remodeling and involved noncanonical (non-Smad-related) signaling. Mouse hearts subjected to pressure overload and treated with a TGF-β-neutralizing Ab had suppressed Smad activation in the interstitium but not in myocytes, and noncanonical (TGF-β-activated kinase 1 [TAK1]) activation remained. Although fibrosis was greatly reduced, chamber dysfunction and dilation persisted. Induced myocyte knockdown of TGF-β type 2 receptor (TβR2) blocked all maladaptive responses, inhibiting myocyte and interstitial Smad and TAK1. Myocyte knockdown of TβR1 suppressed myocyte but not interstitial Smad, nor TAK1, modestly reducing fibrosis without improving chamber function or hypertrophy. Only TβR2 knockdown preserved capillary density after pressure overload, enhancing BMP7, a regulator of the endothelial-mesenchymal transition. BMP7 enhancement also was coupled to TAK1 suppression. Thus, myocyte targeting is required to modulate TGF-β in hearts subjected to pressure overload, with noncanonical pathways predominantly affecting the maladaptive hypertrophy/dysfunction.     

Gastric peroxisome proliferator activator receptor-γ expression and cytoprotective actions of its ligands against ischemia-reperfusion injury in rats

The beneficial effects by peroxisome proliferator-activated receptor-γ (PPAR-γ) on gastric injury induced by ischemia-reperfusion have been confirmed, however, the precise mechanism of its cytoprotection is not elucidated thoroughly. The aim of the present study was to determine the gastric localization of PPAR-γ expression in the rat gastric mucosa, and to clarify the mechanism of its cytoprotective properties. The gastric expression of PPAR-γ was confirmed by RT-PCR and western blot, and localized on gastric epithelial cells. The protective effect of PPAR-γ ligands, pioglitazone or 15-deoxy-Δ(12,14)-prostaglandin J(2), on gastric ischemia-reperfusion injury was reversed by the co-administration with PPAR-γ antagonist. The gastric expression of tumor necrosis factor-α and cytokine-induced neutrophil chemoattractant-1 increased significantly in rats treated ischemia-reperfusion, and these increases were significantly inhibited by treatment with pioglitazone. Among the 1,032 probes, 18 probes were up-regulated at least 1.5-fold, 17 were down-regulated at least 1.5-fold by pioglitazone. The network including calnexin, endoplasmic reticulum stress protein, heat shock proteins, and proteasome genes was induced by pioglitazone treatment. In conclusion, activation of gastric epithelial PPAR-γ receptor by its ligands may represent a novel therapeutic approach for gastric inflammation via up-regulation of heat shock proteins and endoplasmic reticulum-related proteins.     

转化生长因子β1/Smads通路在百草枯中毒所致上皮-间充质转变和肺纤维化中的作用研究

目的本研究通过观察百草枯诱导大鼠肺纤维化中转化生长因子β1（TGF-β1）/Smads信号通路的上皮-间充质转变（EMT）现象及相关蛋白的表达。 方法将60只雄性大鼠分为对照组及百草枯组,每组各30只。百草枯组腹腔注射80 mg/kg百草枯建立中毒模型,对照组注射3 mL等渗NaCl溶液。分别在建模后1、3、7、14、21、28 d分批处死大鼠,比较两组大鼠肺组织湿干比重及羟脯氨酸水平,取左肺下叶予苏木素-伊红（HE）染色及Masson染色。评估肺组织病理学和肺纤维化程度,采用Western-blotting检测百草枯中毒后1、3、7、14、21、28 d肺组织中EMT相关指标和TGF-β1/Smads信号通路相关蛋白的表达。 结果两组各时间点肺湿干比重及羟脯氨酸水平的比较,差异有统计学意义（F=9.772、22.541,P均< 0.001）,且百草枯组湿干比重的比值在3、7、14、21、28 d均显著高于对照组（P均<0.05）,而羟脯氨酸表达水平仅在14、21、28 d明显高于对照组（P均<0.05）。病理结果显示百草枯组大鼠中毒后1~7 d,炎症细胞浸润,肺泡间质增厚水肿,中毒后21 d和28 d可见肺泡壁明显增厚及胶原纤维明显增生,而对照组大鼠肺组织无明显改变。对照组与百草枯组各时间点TGF-β1、Smad2/3、p-Smad2/3、Smad4、p-Smad4、Smad7、p-Smad7、E-cad、α-平滑肌肌动蛋白（α-SMA）、Vimentin和成纤维细胞特异性蛋白1（FSP-1）表达水平的比较,差异均有统计学意义（F=10.685、7.381、7.878、10.743、14.575、17.791、33.200、14.453、10.849、25.415、26.263,P均< 0.001）,且百草枯组TGF-β1、Smad2/3、p-Smad2/3、Smad4、p-Smad4、α-SMA、Vimentin及FSP-1表达水平逐渐升高,中毒后21 d达高峰（P均<0.05）。而Smad7、p-Smad7及E-cad表达水平逐渐降低,Smad7、p-Smad7水平在中毒后7 d达到谷底;E-cad表达水平在中毒后21 d达到谷底（P均<0.05）。 结论TGF-β1/Smads信号通路可能通过调节EMT过程影响百草枯诱导的肺纤维化发生。     

Knockdown of TRIM47 inhibits glioma cell proliferation,migration and invasion through the inactivation of Wnt/β-catenin pathway

Tripartite motif 47 (TRIM47), a member of the TRIM protein family, plays a crucial role in tumor development and progression. However, the role of TRIM47 in glioma has not been investigated. In the present study, we investigated the expression of TRIM47 in glioma and explored the role of TRIM47 in glioma proliferation and migration both in vitro and in vivo. Our results showed that TRIM47 expression was significantly increased in glioma tissues compared to the normal brain tissues. Knockdown of TRIM47 in U87 and U251 cells inhibited cell proliferation, as well as cell migration and invasion. TRIM47 knockdown caused significant increase in E-cadherin expression and remarkable decrease in N-cadherin and vimentin expressions in both U87 and U251 cells. In vivo assay proved that knockdown of TRIM47 prevented tumor growth of glioma. Furthermore, TRIM47 silencing significantly inhibited the activation of Wnt/β-catenin pathway. Additionally, treatment with LiCl reversed the inhibitory effects of TRIM47 knockdown on cell proliferation and migration in U87 cells. In conclusion, these findings indicated that knockdown of TRIM47 suppressed cell proliferation and metastasis of glioma both in vitro and in vivo. TRIM47 exerted an oncogenic role in glioma and might be a therapeutic target for the treatment of glioma.     

Wnt/β-catenin signaling accelerates mouse lung tumorigenesis by imposing an embryonic distal progenitor phenotype on lung epithelium

Although mutations in Kras are present in 21% of lung tumors, there is a high level of heterogeneity in phenotype and outcome among patients with lung cancer bearing similar mutations, suggesting that other pathways are important. Wnt/β-catenin signaling is a known oncogenic pathway that plays a well-defined role in colon and skin cancer; however, its role in lung cancer is unclear. We have shown here that activation of Wnt/β-catenin in the bronchiolar epithelium of the adult mouse lung does not itself promote tumor development. However, concurrent activation of Wnt/β-catenin signaling and expression of a constitutively active Kras mutant (KrasG12D) led to a dramatic increase in both overall tumor number and size compared with KrasG12D alone. Activation of Wnt/β-catenin signaling altered the KrasG12D tumor phenotype, resulting in a phenotypic switch from bronchiolar epithelium to the highly proliferative distal progenitors found in the embryonic lung. This was associated with decreased E-cadherin expression at the cell surface, which may underlie the increased metastasis of tumors with active Wnt/β-catenin signaling. Together, these data suggest that activation of Wnt/β-catenin signaling can combine with other oncogenic pathways in lung epithelium to produce a more aggressive tumor phenotype by imposing an embryonic distal progenitor phenotype and by decreasing E-cadherin expression.     

Epithelial stem cell mutations that promote squamous cell carcinoma metastasis

Squamous cell carcinomas (SCCs) originate in stratified epithelia, with a small subset becoming metastatic. Epithelial stem cells are targets for driver mutations that give rise to SCCs, but it is unknown whether they contribute to oncogenic multipotency and metastasis. We developed a mouse model of SCC by targeting two frequent genetic mutations in human SCCs, oncogene Kras^G12D activation and Smad4 deletion, to mouse keratin 15–expressing (K15⁺) stem cells. We show that transgenic mice developed multilineage tumors, including metastatic SCCs. Among cancer stem cell–enriched (CSC-enriched) populations, those with increased side population (SP) cells correlated with epithelial-mesenchymal transition (EMT) and lung metastasis. We show that microRNA-9 (miR-9) contributed to SP expansion and metastasis, and miR-9 inhibition reduced the number of SP cells and metastasis. Increased miR-9 was detected in metastatic human primary SCCs and SCC metastases, and miR-9–transduced human SCC cells exhibited increased invasion. We identified α-catenin as a predominant miR-9 target. Increased miR-9 in human SCC metastases correlated with α-catenin loss but not E-cadherin loss. Our results demonstrate that stem cells with Kras^G12D activation and Smad4 depletion can produce tumors that are multipotent and susceptible to EMT and metastasis. Additionally, tumor initiation and metastatic properties of CSCs can be uncoupled, with miR-9 regulating the expansion of metastatic CSCs.