Effect of atractylenolide Ⅲ on zearalenone-induced Snail1-mediated epithelial–mesenchymal transition in porcine intestinal epithelium

Background The intestinal epithelium performs essential physiological functions,such as nutrient absorption,and acts as a barrier to prevent the entry of harmful substances.Mycotoxins are prevalent contaminants found in ani-mal feed that exert harmful effects on the health of livestock.Zearalenone(ZEA)is produced by the Fusarium genus and induces gastrointestinal dysfunction and disrupts the health and immune system of animals.Here,we evaluated the molecular mechanisms that regulate the effects of ZEA on the porcine intestinal epithelium.Results Treatment of IPEC-J2 cells with ZEA decreased the expression of E-cadherin and increased the expression of Snai1 and Vimentin,which induced Snail1-mediated epithelial-to-mesenchymal transition(EMT).In addition,ZEA induces Snail-mediated EMT through the activation of TGF-βsignaling.The treatment of IPEC-J2 cells with atractyle-nolideⅢ,which were exposed to ZEA,alleviated EMT.Conclusions Our findings provide insights into the molecular mechanisms of ZEA toxicity in porcine intestinal epi-thelial cells and ways to mitigate it.

LncRNA MEG3 Inhibits the Epithelial-mesenchymal Transition of Bladder Cancer Cells through the Snail/E-cadherin Axis

Objective This study aimed to investigate the role of the long noncoding RNA(lncRNA)maternally expressed gene 3(MEG3)in the epithelial-mesenchymal transition(EMT)of bladder cancer cells and the potential mechanisms.Methods Cell invasion,migration,and wound healing assays were conducted to assess the effects of MEG3 on the invasive and migratory capabilities of bladder cancer cells.The expression levels of E-cadherin were measured using Western blotting,RT-qPCR,and dual luciferase reporter assays.RNA immunoprecipitation and pull-down assays were performed to investigate the interactions between MEG3 and its downstream targets.Results MEG3 suppressed the invasion and migration of bladder cancer cells and modulated the transcription of E-cadherin.The binding of MEG3 to the zinc finger region of the transcription factor Snail prevented its ability to transcriptionally repress E-cadherin.Additionally,MEG3 suppressed the phosphorylation of extracellular regulated protein kinase(ERK),c-Jun N-terminal kinase(JNK),and P38,thereby decreasing the expression of Snail and stimulating the expression of E-cadherin.Conclusion MEG3 plays a vital role in suppressing the EMT in bladder cancer cells,indicating its potential as a promising therapeutic target for the treatment of bladder cancer.

A Record of the Invasive Golden Apple Snail Pomacea canaliculata (Lamarck 1819) at Black Dragon Spring,Dianchi Basin

The golden apple snail Pomacea canaliculata （Lamarck 1819） was first recorded at Black Dragon Spring, Dianchi Basin, Baiyi Township, Songming County, Kunming City, Yunnan Province, China, in October 2004. The water from the spring flows into the Songhuaba Reservoir, the major drinking water resource for Kunming City, and part of the Dianchi Lake basin. This is the first record of this invasive snail in the Dianchi Lake Basin. Pomacea canaliculata originates from Central and South America, and in Asia the snail has spread through deliberate and accidental introductions to the Philippines, Vietnam, Thailand, Laos, Cambodia, Malaysia, Indonesia, Papua New Guinea, Korea, Japan and South China. It has become a major pest in rice-growing areas, resulting in huge damage to crops. Strict prevention and control measures have to be implemented to prevent the spread of the snail in Yunnan, together with public awareness campaigns to inform the public of the dangers of this invasive snail.

山丘区土壤环境因子对钉螺(Oncomelania Snail)分布的影响

土壤是自然界钉螺孳生繁殖的重要场所，钉螺的分布与土壤环境因子密切相关。对山丘区9种不同土地利用类型土壤环境对钉螺分布影响的研究结果表明：耕地、荒草地、河滩地及灌溉沟渠存在钉螺分布，活螺框出现率的高低顺序为耕地〉河滩地〉灌溉沟渠〉荒草地，活螺密度的大小顺序为河滩地〉灌溉沟渠〉耕地〉荒草地;有螺土壤环境与无螺土壤环境的方差分析结果不显著，土壤全K含量与0.02-0.002mm的土壤颗粒含量存在显著差异;土壤环境因子对钉螺分布影响的灰色关联分析表明，0.02-0.002mm的土壤颗粒、土壤全P含量和土壤水分是影响钉螺的最重要的3个因子，且土壤环境因子对钉螺活螺框出现率及活螺密度影响的大小规律基本一致，不同之处在于土壤全K含量对活螺密度的影响更显著。研究结果可为我国山丘区改造钉螺孳生环境、控制血吸虫病流行及发展区域经济提供依据。

COQ10B在食管鳞癌中的表达及其调控Snail表达促进食管鳞癌细胞增殖与侵袭

目的:探讨COQ10B对食管鳞癌细胞增殖、侵袭能力的影响及可能的分子机制。方法:通过TIMER2.0数据库分析COQ10B基因在各种肿瘤和相邻正常组织之间的表达水平。免疫组织化学检测COQ10B在食管鳞癌组织中的表达水平并进行临床病理特征分析及生存分析;利用慢病毒构建COQ10B敲减稳转株及Snail过表达稳转株,qRT-PCR和Western blot方法检测转染效率。MTT法、Celigo细胞计数及Transwell侵袭小室检测COQ10B对KYSE150细胞系增殖和侵袭能力的影响。通过GEPIA2数据库分析COQ10B表达水平与Snail的相关性;Western blot检测敲减COQ10B对Snail蛋白表达的影响。通过拯救实验分析COQ10B是否通过正调控Snail促进KYSE150细胞系增殖和侵袭能力。结果:COQ10B在ESCC组织及细胞系中均为高表达水平,且表达水平与临床病理特征病理分级相关。COQ10B与ESCC患者预后相关,高表达COQ10B的ESCC患者预后明显较差,且发现性别、肿瘤TNM分期是影响ESCC预后的独立危险因素。敲减COQ10B可降低ESCC细胞增殖及侵袭能力。COQ10B表达水平与Snail呈正相关,并通过正调控Snail促进KYSE150细胞系增殖和侵袭能力。结论:COQ10B通过正向调控Snail基因表达促进食管鳞癌增殖与侵袭。

结肠腺癌组织中Cripto-1蛋白和锌指转录因子Snail与基质金属蛋白酶-9的表达及临床意义

目的研究结肠腺癌组织中畸胎瘤衍生生长因子-1(Cripto-1)、锌指转录因子(Snail)和基质金属蛋白酶-9(MMP-9)的表达情况及临床病理特征。方法回顾性分析2020年1月至2021年8月于韶关市粤北人民医院胃肠外科92例行手术切除结肠腺癌患者的临床资料,手术切除标本92个。另选取癌旁不典型增生组织56例和正常结肠组织35例作为对照。采用免疫组化检测并比较Cripto-1、Snail和MMP-9在结肠腺癌组织、不典型增生和正常结肠黏膜组织中的表达情况,采用Spearman相关分析Cripto-1、Snail和MMP-9与结肠腺癌临床病理特征的相关性。结果结肠腺癌、不典型增生、正常结肠组织的CR-1、Snail和MMP-9阳性率比较差异有统计学意义(P<0.05);结肠腺癌及不典型增生组织中CR-1、Snail和MMP-9阳性率均高于正常结肠组织,结肠腺癌组织中Snail和MMP-9阳性率均高于不典型增生组织,差异均有统计学意义(P<0.05);结肠腺癌组织与不典型增生组织中CR-1阳性率比较差异无统计学意义。肿瘤的浸润深度、临床TNM分期及淋巴结转移情况不同的患者Cripto-1、Snail和MMP-9在结肠腺癌组织中的表达阳性率比较差异有统计学意义(P<0.05)。肿瘤浸润T3~T4、临床分期Ⅲ~Ⅳ期、有淋巴结转移的患者结肠腺癌组织中CR-l、Snail和MMP-9的表达阳性率均高于肿瘤浸润T1~T2、临床分期Ⅰ~Ⅱ期和无淋巴结转移的患者,差异有统计学意义(P<0.05)。结肠腺癌组织中CR-1表达与Snail和MMP-9的表达呈正相关(r>0,P<0.05),MMP-9表达与Snail表达亦呈正相关(r>0,P<0.05)。结论Cripto-1、Snail和MMP-9在结肠癌的浸润和转移中起协同调节作用。

Effects of AIBL on Oncomelania hupensis,the intermediate snail host of Schistosoma japonicum:An enzyme histochemical study

Objective:To explore the effect of AIBL on Oncomelania hupensis,the intermediate snail host of Schistosoma japonicum.Methods:The enzyme histochemical profiles of cholineslerase, cytochrome oxidase,lactate dehydrogenase,nitric oxide synthase,and succinate dehydrogenase in the soft tissues of Oncomelania hupensis,the intermediate host snail of Schistosoma japonicum, were analyzed before and after treatment with the active ingredient of Buddleia lindleyana(AIBL), a potent and safe plant molluscicide.Results:Treatment with AIBL induced a notable decrease in the activities of the five enzymes(P【0.01).Conclusions:The results indicate that AIBL impairs the activities of the enzymes,thereby influencing the transfer of neurotransmitter and energy supply in Oncomelania hupensis and ultimately harming their various physiological functions, which are considered to cause death of the species.

Nrf2 inhibits epithelial-mesenchymal transition by suppressing snail expression during pulmonary fibrosis

OBJECTIVE Epithelial-mesenchymal transition(EMT)is a phenotype conversion that plays a critical role in the development of pulmonary fibrosis(PF).It is known that a transcription factor snail could regulate the progression of EMT.Nuclear factor erythroid 2 related factor 2(Nrf2),a key regulator of antioxidant defense system,protects cells and tissues against oxidative stress.However,it is not known whether Nrf2 regulates snail thereby modulating the development of PF.MEHODS Bleomycin(BLM)was intratracheally injected into both Nrf2-knockout(Nrf2-/-)and wild-type mice to compare the development of PF.Rat type II alveolar epithelial cells(AECs)RLE-6TN were treated with a specific Nrf2activator sulforaphane,or transfected with Nrf2 and snail si RNAs to determine their effects on transforming growth factorβ1(TGF-β1)-induced EMT.RESULTS BLM-induced EMT and lung fibrosis were more severe in Nrf2-/-mice compared to wild-type mice.In vitro,sulforaphane treatment attenuated TGF-β1-induced EMT,accompanied by the down-regulation of snail.Inversely,silencing Nrf2 by si RNA enhanced TGF-β1-induced EMT along with the expression of snail.Interestingly,silencing snail by si RNA reduced TGF-β1-induced EMT even in the presence of sulforaphane in RLE-6TN cells.CONCLUSION These findings suggested that Nrf2 may attenuate EMT and fibrosis process through regulating the expression of snail in PF.

Epidemiological situation and molecular identification of cercarial stage in freshwater snails in Chao-Phraya Basin, Central Thailand

Objective: To investigate the prevalence of cercarial trematode infection in snails and to examine the reconstruction of the phylogenetic relationship to explain the molecular system of cercarial stage trematodes to estimate the infection rate of in the definite host from the Chao-Phraya Basin.Methods: The snails were collected from 10 provinces of the Chao-Phraya Basin,Thailand by stratified sampling method. The snails were examined for cercarial infection by the crushing method. All DNA specimens were amplified with internal transcribed spacer 3(ITS3) and ITS4 primer based on PCR technique. The sequence data were aligned and used to reconstruct the phylogenetic tree by unweighted pair-group method with arithmetic means with 10 000 bootstraps.Results: The overall rate of cercarial infection was found to be 5.90%(122/2 067). Snails in the family Thiaridae were found to be in the highest prevalence followed by Lymnaeidae, Bithyniidae, Planorbidae, Viviparidae, and Ampullariidae, respectively, while the Buccinidae family(Clea helena) did not reveal any infections. The frequently found species of cercariae were parapleurolophocercous cercariae, cercariae and megarulous cercariae. The monophyletic tree separated the snails into five groups comprised of Heterophyidae, Strigeidae, Lecithodendriidae, Philophthalmidae and Echinostomatidae using the sequence of Angiostrongylus cantonensis as an out-group.Conclusions: This study was the first to report on cercarial infection in the Chao-Phraya Basin, Thailand. This revealed that a high variety of freshwater snails were infected by cercariae stage trematodes with a high prevalence. The sequence data of ITS2 can be used to investigate the phylogenetic relationships of trematodes at the family level and in each clade of different families separated by the definitive hosts.

A Defect Formation as Snail Trails in Photovoltaic Modules

In this paper, we discussed the field failures of the brownish discolored lines like snail trails in PV modules. We were successful simulation snail trails in laboratory and outdoor field. We had found out some types EVA (ethylene vinyl acetate) encapsulants and back sheets which had the serious snail trails but others were snail trails free. Furthermore, according to IEC 61215 accelerated aging testing, we also found only within 2% power loss after these modules impacted by snail trails. The main power losses over 5% were come from cell micro cracks before snail trail formation. That snail trails occurrence means solar cells should have micro cracks. In here, we contributed the snail trail effects and avoided the failures in future photovoltaic modules performance.

Methyltransferase like 13 mediates the translation of Snail in head and neck squamous cell carcinoma

Methyltransferase like 13(METTL13),a kind of methyltransferase,is implicated in protein binding and synthesis.The upregulation of METTL13 has been reported in a variety of tumors.However,little was known about its potential function in head and neck squamous cell carcinoma(HNSCC)so far.In this study,we found that METTL13 was significantly upregulated in HNSCC at both mRNA and protein level.Increased METTL13 was negatively associated with clinical prognosis.And METTL13 markedly affected HNSCC cellular phenotypes in vivo and vitro.Further mechanism study revealed that METTL13 could regulate EMT signaling pathway by mediating enhancing translation efficiency of Snail,the key transcription factor in EMT,hence regulating the progression of EMT.Furthermore,Snail was verified to mediate METTL13-induced HNSCC cell malignant phenotypes.Altogether,our study had revealed the oncogenic role of METTL13 in HNSCC,and provided a potential therapeutic strategy.

Modifi cation of wheat bran insoluble and soluble dietary fibers with snail enzyme

Insoluble dietary fiber(IDF)and soluble dietary fiber(SDF)extracted from wheat bran were modifi ed by snail enzyme and their physicochemical properties(water retention capacity and oil retention capacity),functional properties(cholesterol adsorption capacity,glucose adsorption capacity and antioxidant activity)and structural characterizations were evaluated.The results showed that snail enzyme modification led to the significant increase in oil retention capacity of IDF,glucose adsorption capacity and cholesterol adsorption capacity of IDF and SDF.Enzymatic modification also markedly improved the DPPH radical scavenging capacity and reducing power of IDF and SDF.Meanwhile,scanning electron microscopy(SEM)analysis indicated the microstructures of IDF and SDF powders were signifi cantly changed.Fourier transfer-infrared spectrometry(FT-IR)showed that snail enzyme modifi cation could degrade the part of cellulose and hemicellulose of IDF and SDF.All these improved physicochemical and functional properties of IDF and SDF might depend on their structural changes.It suggested that snail enzyme modifi cation could effectively improve physicochemical and functional properties of IDF and SDF from wheat bran.

Effects of key species mud snail Bullacta exarata (Gastropoda) on oxygen and nutrient fluxes at the sediment-water interface in the Huanghe River Delta, China

Since the mud snail Bullacta exarata was introduced for economic aquaculture in the Huanghe River(Yellow River) Delta in 2001, its quick population growth and expanded distribution make it a key-species in the intertidal zone of this area. This significantly contributed to the economic income of the local people, but its potential ecological impact on the benthic ecosystem remains unknown. A mesocosm study was conducted to test whether its bioturbation activities affect the microphytobenthos(MPBs;i.e., sedimentary microbes and unicellular algae)productivity and the nutrient exchange between the sediment-water interface. Our results show that the mud snail significantly impacted the dissolved oxygen(DO) flux across the sediment-water interface on the condition of normal sediment and light treatment, and significantly increased the ammonium efflux during recovery period in the defaunated sediment and dark treatment. The presence of micro-and meiofauna significantly increased the NH4-N flux in dark treatment. Whereas, in light treatment, these small animals had less effects on the DO and NH4-N flux between sediment-water interface. Our results provide better insight into the effect of the mud snail B.exarata on the ecosystem functioning via benthic fluxes.

Developmental stages and quality traits of giant African land snails [<i>Archachatina marginata</i>(swainson)] eggs

Sixty sexually mature purebred black-skinned Archachatina marginata snails with weight ranging from 120.50 g to 135.70 g were used to generate eggs in this study. The eggs collected were incubated in a chamber filled with loamy soil for appropriate observation and assessment (cracking at four days intervals to check snailet’s development). Results obtained from the study showed that at laying snail egg weights ranged from 1.54 - 2.45 g (mean of 2.00 g). The egg lengths and widths ranged from 13.50 - 16.90 mm (mean of 15.20 mm) and 10.00 - 12.70 mm (mean of 11.40 mm) respectively. The results also revealed that at laying (day one) the egg content was translucent or clear (blank) when observed with light from a powered microscope. Observation of eggs on day four showed the formation of embryo with a semi-transparent cup attached to a long string body. On day 12, some specific organs of the snailet had developed, and there was a reduction in the liquid content. On day 28, the snailet was fully formed, but the shell still contained very small volume of liquid. The snailet hatched on day 29.

Nutritional status of four species of giant land snails in Nigeria

Four species of African giant land snails （Archachatina marginata （ovum ） Pfeiffer, Archachatina marginata （saturalis ） Philippi, Achatina achatina and Limicolaria spp.） were assessed for their proximate and mineral compositions aimed at establishing their nutritive values on wet weight basis. Analysis of muscle revealed that composition of crude protein varied from 18.66%±0.57% in Limicolaria spp. and 20.56%±L0.05% in Archachatina marginata （ovum） Pfeiffer; moisture content was 76.56%±0.04% in Archachatina marginata （ovum） Pfeiffer and 78.68%±0.68% in Limicolaria spp. and ash was 1.34%±0.02% in Achatina achatina and 1.44%±0.01% in Archachatina marginata （ovum） Pfeiffer. These values were statistically different from each other （P〈0.05）. Carbohydrate and fat content were generally low. Crude fibre was not detected in any of the species. The concentrations of zinc, iron, manganese, magnesium, calcium, phosphorus, sulphur, potassium and sodium in the flesh of the snails were determined. Values of iron, magnesium, calcium, phosphorus, potassium and sodium were consistently high while cobalt, copper and lead were not detected. Snails complement the required trace and minor elements needed for proper growth and development in human being, so it is recommended for regular consumption.

Spatial analysis of snail distribution in Jiangning county

Objective: To explore the spatial distribution of oncomelenia snails in Jiangning County. Methods: Cluster analysis and the Spatial Scan Statistics were performed based on the density of alive-snails in habitats and its rate infected by the 5. japonicum. Results : Although areas of snail habitats and density of the alive-snails in marshland in 2000 are higher significantly than that in mountain areas in Jiangning County, the numbers of habitats in mountain are more than that in marshland and they distributed sporadically. The snail habitats were classified into 4 in marshlands and 3 classes in mountain areas respectively in cluster analysis. Although they are mainly the one with low density of alive and infected snails, we should alert that there are also some habitats with high snail density and infection rate, which is important for the transmission of schis-tosomia. The analysis of Spatial Scan Statistics detected 2 significant spatial aggregations for alive-snail in marshland and 4 in mountain areas respectively with p-values less than 0. 01. There are also 2 significant spatial aggregations for infected snails in marshland. Conclusion: The significant spatial aggregations for alive-snails and infected snails indicated that there are some factors in the habitats suitable for the survival of snails and the transmission of schistosomia.

Ecology and Species Composition of Fresh Water Snails in Amassoma Community and Niger Delta University Campuses, Bayelsa State, Nigeria

The knowledge about the population dynamics of freshwater snail intermediate host and their roles in disease transmission is little known in Bayelsa State. This study investigated the species composition of fresh water snail intermediate host in Amassoma community and the Niger Delta University Campuses during August 2019-October 2019 across five locations (Main campus Hostel, E.T.F Building, Ogboebi-Ama, Efeke-Ama, Ogbopina). Snails were collected from the water bodies with the aid of a scooping net and hand picking. The morphological identification of the snail intermediate host followed standard procedures. From the result, five hundred and seventy-one freshwater snails belonging to four genera and five species were recorded. The presence of Lymnae and Bulinus in the locations highlights foci for fascioliasis and schistosomiasis. The presence of Melanoides spp. is novel in Bayelsa State. The public health implications of these snails have called for timely control intervention.

Studies on Mechanical and End-Use Properties of Natural Rubber Filled with Snail Shell Powder

A series of natural rubber-snail shell powder vulcanizates were compounded on a two-roll mill, and moulded on a compression moulding machine. The mechanical and end-use properties of the natural rubber vulcanizates were investigated at snail shell powder contents, 0 to 20 pphr. The snail shell powder was characterized for filler properties and sieved to 0.075, and 0.30 μm particle sizes. Carbon black was used as the reference filler. Results showed that the tensile strength, modulus, elongation at break, and resilience of the rubber vulcanizates were not enhanced on addition of snail shell powder. The hardness of the rubber vulcanizes were marginally increased at high snail shell powder content. However, the specific gravity of the rubber vulcanizates showed increases with increase in snail shell powder content. At a filler content above 5 pphr, snail shell powder exhibited good flame retardant property in the vulcanizates. The swelling indices of snail shell powder (0.075 μm) filled natural rubber were generally good, and better than those of snail shell powder (0.30 μm) filled natural rubber. Carbon black was found to show more property improvement for the natural rubber vulcanizates when compared to snail shell powder. Although the mechanical properties of snail shell powder filled natural rubber vulcanizates were not good, there were improvements in the end-use properties, an indication that snail shell powder could still find utilization in the rubber industry where specific end-use property of a rubber product is required.

山奈酚调节AKT/GSK-3β/Snail信号通路对鼻咽癌细胞增殖、凋亡和上皮间质转化的影响

目的:探讨山奈酚对鼻咽癌细胞增殖、凋亡和上皮间质转化(EMT)的影响,并探究其作用机制。方法:将CNE-2细胞分为对照组、山奈酚低浓度组、山奈酚中浓度组、山奈酚高浓度组、山奈酚高浓度+SC-79(AKT激活剂)组。CCK-8法和克隆实验测定细胞增殖,流式细胞术检测细胞凋亡,Western blot检测各蛋白B淋巴细胞瘤-2(Bcl-2)、Bcl-2相关X蛋白(Bax)、天冬氨酸蛋白水解酶-3(Caspase-3)、波形蛋白(Vimentin)、上皮钙黏蛋白(E-cadherin)、神经钙黏蛋白(N-cadherin)、蛋白激酶B(AKT)、磷酸化Akt(p-AKT)、糖原合成酶激酶3β(GSK-3β)、磷酸化GSK-3β(p-GSK-3β)、Snail的表达水平。构建鼻咽癌裸鼠模型,分为裸鼠NC组、山奈酚组、山奈酚+SC-79组,测量肿瘤质量与体积,免疫组化法检测移植瘤组织p-AKT、p-GSK-3β、Snail蛋白表达。结果:山奈酚对人鼻咽癌上皮细胞活力无显著影响(P>0.05);鼻咽癌细胞活力随着山奈酚浓度的升高而逐渐降低(P<0.05),选择CNE-2作为后续实验细胞,选择25、50、100μmol/L山奈酚作为后续实验浓度。与对照组相比,山奈酚低、中、高组细胞活力、Bcl-2、N-cadherin、Vimentin、p-AKT/AKT、p-GSK-3β/GSK-3β、Snail水平显著下降,凋亡率、Bax、Caspase-3、E-cadherin上升(P<0.05);与山奈酚高浓度组相比,山奈酚高浓度+SC-79组细胞活力、Bcl-2、N-cadherin、Vimentin、p-AKT/AKT、p-GSK-3β/GSK-3β、Snail水平显著上升,凋亡率、Bax、Caspase-3、E-cadherin下降(P<0.05)。山奈酚能抑制移植瘤质量和体积,降低p-AKT、p-GSK-3β、Snail蛋白表达(P<0.05);SC-79逆转山奈酚对移植瘤的抑制作用,促进AKT/GSK-3β/Snail通路蛋白表达(P<0.05)。结论:山奈酚能抑制鼻咽癌细胞增殖和EMT,促进细胞凋亡,其作用机制可能与抑制AKT/GSK-3β/Snail信号通路有关。

Transcriptional Factor Snail Mediates Epithelial-Mesenchymal Transition in Human Bronchial Epithelial Cells Induced by Silica

Epithelial-mesenchymal transition （EMT） plays an important role in fibrotic diseases. We have previously showed that silica induces EMT in human bronchial epithelial cells （BECs）; however, the underlying mechanism of silica-induced EMT is poorly understood. In the present study, we investigated the role of Snail in silica-induced EMT in human BECs in vitro. Human BECs were treated with silica at various concentrations and incubation times. Then MTr assay, western blot, electrophoretic mobility shift assay （EMSA）, and small interfering RNA （siRNA） transfection were performed. We found that silica increased the expression and DNA binding activity of Snail in human BECs. SNAI silica-induced expression siRNA upregulated the siRNA inhibited the of Snail. Moreover, SNAI expression of epithelial marker E-cadherin, but attenuated the expression of mesenchymal marker a-smooth muscle actin and vimentin in silica-stimulated cells. These results suggest that Snail mediates the silica-induced EMT in human BECs.