Detection of circulating hepatocellular carcinoma cells in peripheral venous blood by reverse transcription-polymerase chain reaction

Objective: To detect circulating hepatocellular carcino-ma by demonstrating hepatocellular carcinoma cells orhepatocyte-associated mRNA in the nuclear cell com-ponent of peripheral blood (PBL).Methods: Peripheral blood (5 ml) samples were ob-tained from 93 patients with hepatocellular carcinoma(HCC) and from 33 control subjects (9 with liver cir-rhosis after hepatitis B,14 with chronic hepatitis B,10with normal liver function). To identify HCC cells inperipheral blood, liver-specific human alpha-fetopro-tein (AFP) mRNA was amplified from total RNA ex-tracted from whole blood by reverse transcription-polymerase chain reaction.Results: AFPmRNA was detected in 50 blood samplesfrom the HCC patients (50/93, 53.8%). In contrast,there were no clinical control patients whose samplesshowed detectable AFPmRNA in PBL. The presence ofAFPmRNA in blood seemed to be correlated with thestage (by TNM classification) of HCC, the serum AFPvalue, and the presence of intrahepatic metastasis,portal vein thrombosis, tumor diameter and/or distantmetastasis. In addition, AFPmRNA was detected in theblood of 21 patients with metastasis at extrahepaticorgans (100%) in contrast to 29 (40.3%)of 72 pa-tients without metastasis.Conclusion: The presence of AFPmRNA in peripheralblood may be an indicator of malignant hepatocytes,which might predict hematogenous spreading metasta-sis of tumor cells in patients with HCC.

Exogenous reference gene normalization for real-time reverse transcription-polymerase chain reaction analysis under dynamic endogenous transcription

Quantitative real-time reverse transcription-polymerase chain reaction （qPCR） is widely used to investigate transcriptional changes following experimental manipulations to the nervous system. Despite the widespread utilization of qPCR, the interpretation of results is marred by the lack of a suitable reference gene due to the dynamic nature of endogenous transcription. To address this inherent deficiency, we investigated the use of an exogenous spike-in mRNA, luciferase, as an internal reference gene for the 2ct normalization method. To induce dynamic transcription, we systemically administered capsaicin, a neurotoxJn selective for C-type sensory neurons expressing the TRPV-1 receptor, to adult male Sprague-Dawley rats. We later isolated nodose ganglia for qPCR analysis with the reference being either exogenous luciferase mRNA or the commonly used endogenous reference 13-111 tubulin. The exogenous luciferase mRNA reference clearly demonstrated the dynamic expression of the endogenous reference. Furthermore, variability of the endogenous reference would lead to misinterpretation of other genes of interest. In conclusion, traditional reference genes are often unstable under physiologically normal situations, and certainly unstable following the damage to the nervous system. The use of exogenous spike-in reference provides a consistent and easily implemented alternative for the analysis of qPCR data.

Positive reverse transcription-polymerase chain reaction assay results in patients recovered from COVID-19: Report of two cases

BACKGROUND Coronavirus disease 2019(COVID-19)has spread around the globe.On February 28,2020,the World Health Organization adjusted the risk of spread and impact of COVID-19 to“very high”at the global level.Studies have mainly focused on the etiology,epidemiology,and treatment of COVID-19 to limit further spread and the negative impact of the disease,while less attention has been devoted to the follow-up and reexamination of patients who recovered from COVID-19 or were released from quarantine.CASE SUMMARY This study reports two cases where patients who had negative reverse transcription-polymerase chain reaction(RT-PCR)test results and met the criteria for discharge subsequently had positive RT-PCR test results.The clinical manifestations and computed tomography(CT)findings of these patients were examined.The conversion of RT-PCR test results in these two patients may be related to false-negative and false-positive outcomes of the test.CT images helped track improvement of pulmonary lesions.CONCLUSION The timing of discharge of COVID-19 patients should be determined by comprehensive analysis of CT images and RT-PCR test results.

Detection of hepatocellular carcinoma cells in the peripheral blood with reverse--transcription polymerase chain reaction

In order to detect circulating cells of hepatocellular carcinoma(HCC) in the peripheral blood with reverse transcripition polymerase chain reaction (RT-PCR ), alpha-fetoprotein (AFP ) mRNA was tested in the blood samples of 113 cases of HCC and 69 controls (including 30 cases of liver cirrhosis, 9 cases of metastatic liver cancer and 30 normal subjects). 20/43 (46. 5% ) cases of HCC and 2/30 (6. 7% ) cases of liver cirrhosis are positive and the cases of nletastatic liver cancer and normal controls were negative for human AFP(hAFP) rnRNA. The presence of hAFP mRNA in the peripheral blood seems to be correlated with intrahepatic and distant nletastasls of HCC and portal vein thrombosis. It is concluded that the presence of hAFP mRNA in the peripheral hloocl is an indicator of circulating HCC cells and can be used to diagnose the rnetastasisof HCC through henlatogenous route and RT-PCR amplification of hAFP mRNA is a sensitive and specificprocedure for detecting circulating cells of HCC.

Selection and Evaluation of Optimal Reference Genes for Quantitative Reverse Transcription-Polymerase Chain Reaction Analyses of Gene Expression in Human Spermatozoa

Objective:Optimal reference genes are critical for accurate normalization and reliable interpretation of gene expression quantification data.Recently,several strategies have been utilized for validating reference genes in different human tissues.However,no universal reference genes have been described that accurately summarize transcriptional activity in human spermatozoa.Methods:Using quantitative reverse transcription-polymerase chain reaction(RT-qPCR),we evaluated ten commonly used candidate reference genes between two groups of human cryopreserved donor sperm with different pregnancy rates.We assessed the stability of reference genes using three different algorithms,namely geNorm,NormFinder,and BestKeeper.We then identified the most stable reference genes.Results:Male-enhanced antigen 1(MEA1)was identified as the most stably expressed reference gene,followed by testis-enhanced gene transcript(TEGT).Conclusions:We comprehensively identified MEA1 and TEGT as the most stably expressed reference genes for the normalization of gene expression data in human spermatozoa.

Diagnosis of West Nile virus infections:Evaluation of different laboratory methods

BACKGROUND The diagnosis of West Nile virus(WNV)is challenging due to short-term and low-level viremia,flavivirus cross-reactivity,and long immunoglobulin M(IgM)persistence.AIM To evaluate different methods for WNV detection[reverse transcription-polymerase chain reaction(RT-PCR),IgM/IgG antibodies,IgG avidity]in serum,cerebrospinal fluid(CSF),and urine samples of patients with confirmed WNV infection.METHODS The study included patients with confirmed WNV neuroinvasive infection(n=62),asymptomatic WNV seropositive individuals(n=22),and individuals with false-positive WNV IgM antibodies(n=30).WNV RNA was detected using RT-PCR.A commercial ELISA was used to detect WNV IgM/IgG antibodies with confirmation of cross-reactive samples using a virus neutralization test(VNT).IgG-positive samples were tested for IgG avidity.RESULTS The WNV-RNA detection rates were significantly higher in the urine(54.5%)/serum(46.4%)than in CSF(32.2%).According to the sampling time,the WNV-RNA detection rates in urine collected within 7 days/8-14/≥15 days were 29.4/66.6/62.5%(P=0.042).However,these differences were not observed in the CSF.The median RT-PCR cycle threshold values were significantly lower in urine(32.5,IQR=28-34)than in CSF(34.5,IQR=33-36).The frequency of positive WNV IgM and IgG significantly differed according to the sampling time in serum but not in CSF.Positive IgM/IgG antibodies were detected in 84.3/9.3%of serum samples collected within 7 days,100/71.1%of samples collected 8-14,and 100%samples collected after≥15 days.Recent WNV infection was confirmed by low/borderline avidity index(AI)in 13.6%of asymptomatic individuals.A correlation between ELISA and AI was strong negative for IgM and strong positive for IgG.No significant correlation between ELISA IgG and VNT was found.CONCLUSION The frequency of WNV RNA and antibody detection depends on the sampling time and type of clinical samples.IgG avidity could differentiate recent WNV infections from long-persisting IgM antibodies.

Msi1基因沉默对人肝癌HepG2细胞的影响

目的:探讨siRNA沉默Msi1基因表达后,人肝癌HepG2细胞的增殖与凋亡的情况。方法:设计合成针对Msi1 mRNA序列的siRNA多条序列,分别转染人肝癌HepG2细胞。使用RT–PCR方法检测各组细胞Msi1基因表达情况;Western blot法检测survivin蛋白、caspase3蛋白表达情况;MTT法、平皿克隆实验检测HepG2细胞增殖情况;流式细胞术检测各组HepG2细胞凋亡情况。结果:(1)RT-PCR结果:转染后24 h后,序列a,b,c转染效率分别为65%,64%及62%。其抑制率分别是Msi1 siRNAa(68%)、Msi1 siRNAb(56%)、Msi1 siRNAc(35%)。(2)流式细胞术检测各组细胞凋亡:空白组、阴性组、脂质体组、Msi1 siRNAa组凋亡率分别为(4.14±0.26)%、(4.51±0.78)%、(4.19±1.21)%,(16.8±0.26)%,Msi1 siRNAa组与空白对照组比较差异有统计学意义(P<0.05)。(3)Msi1 siRNAa最能有效抑制肝癌HepG2细胞中Msi1表达,与空白对照组比较,Msi1 siRNAa组HepG2细胞生长、增殖速度明显减缓(P<0.05);survivin蛋白表达水平显著下调(P<0.05),而caspase3蛋白表达水平上调(P<0.05);Msi1 siRNAa组凋亡率增高(P<0.05)。结论:沉默Msi1可抑制人肝癌HepG2细胞的增殖,诱导其凋亡。

Role of microRNAs in gastric cancer

Although gastric cancer(GC)is one of the leading causes of cancer-related death,major therapeutic advances have not been made,and patients with GC still face poor outcomes.The prognosis of GC also remains poor because the molecular mechanisms of GC progression are incompletely understood.MicroRNAs(miRNAs)are noncoding RNAs that are associated with gastric carcinogenesis.Studies investigating the regulation of gene expression by miRNAs have made considerable progress in recent years,and abnormalities in miRNA expression have been shown to be associated with the occurrence and progression of GC.miRNAs contribute to gastric carcinogenesis by altering the expression of oncogenes and tumor suppressors,affecting cell proliferation,apoptosis,motility,and invasion.Moreover,a number of miRNAs have been shown to be associated with tumor type,tumor stage,and patient survival and therefore may be developed as novel diagnostic or prognostic markers.In this review,we discuss the involvement of miRNAs in GC and the mechanisms through which they regulate gene expression and biological functions.Then,we review recent research on the involvement of miRNAs in GC prognosis,their potential use in chemotherapy,and their effects on Helicobacter pylori infections in GC.A greater understanding of the roles of miRNAs in gastric carcinogenesis could provide insights into the mechanisms of tumor development and could help to identify novel therapeutic targets.

Correlation between MMP-2 and NF-κ B expression of intracranial aneurysm

Objective:To investigate the correlation between expressions of MMP-2 and NF-κB in the intracranial aneurysm wall,and explore their role in the mechanism of the occurrence,growth and rupture of intracranial aneurysms.Methods:RT-PCR was used to detect the expression of MMP-2 and NF-κB mRNA of 30 cases of intracranial aneurysm tissue and 10 cases of normal intracranial arterial tissue:Immunohistochemical method was used to detect the expression of MMP-2 and NF-κB protein.Results:the semi-quantitative analysis of MMP-2 and NF-κB in aneurysms tissues and normal tissues were statistically significant different from each other(P【0 05).Immunohistochemical staining results showed NF-κB was expressed in different layers.The expression of them were positive in intimal and medial,and the expression sites were located in the nucleus.MMP-2 were expressed in different layers of the aneurysm wall,and the expressions were positive in media and extima.The MMP-2 and NF-κB-positive expression of aneurysm wall were significantly higher than in normal cerebral arteries(P【0.05).MMP-2 and NF-κB mRNA expression showed positive correlation in the aneurysm wall tissue(r = 0.689,P = 0.005). Conclusions:The expressions of MMP-2 and NF-κB in the intracranial aneurysm wall tissue were significantly higher than in the normal intracranial arterial tissues.They have a synergistic effect on the formation of intracranial aneurysms.

Overexpression of polo-like kinase1 predicts a poor prognosis in hepatocellular carcinoma patients

AIM： To elucidate the role of overexpressed polo-like kinasel （PLK1）in hepatocellular carcinoma （HCC）. METHODS： We prospectively collected clinicopathological, immunohistochemical and semi-quantitative reverse transcription-polymerase chain reaction （RT-PCR） data from 135 HCC patients undergoing successful hepatectomy. The correlations between PLK1 mRNA expression and clinicopathologic variables were analyzed by Mann-Whitney U test. Prognostic factors were identified by univariate and multivariate analyses. RESULTS： Immunohistochemical results showed overexpression of PLK1 was mainly found in tumor tissues compared with tumor-free tissue. A similar mRNA result was obtained by semi-quantitative RT-PCR. A total of 111 samples were positive for PLK1 mRNA expression. The positive expression was correlated with venous invasion, tumor nodules and Edmondson grade. Furthermore, 1, 3, 5-year survival rates in the positive expression group were significantly lower than the negative control group. Multivariate analysis showed that positive PLK1 expression was an independent risk factor for HCC. CONCLUSION： PLK1 could be a potential biomarker for diagnosis and therapy for HCC.

Analysis of Survivin Expression in the Subtypes of Lymphoma

Objective： To detect the expression of survivin in subtypes of lymphoma and its value in classifying subtypes of lymphoma. Methods： Paraffin-embedded samples collected from 219 cases of lymphoma and 13 cases of lymph node reactive proliferation from affiliated hospitals of Sun Yat-sen University during 2001-2003 were examined for the expression of survivin by using immunohistochemical staining. Reverse transcription-polymerase chain reaction （RT-PCR） was used to detect the mRNA expression of survivin in K562, HL60, Raji, and Jurkat cell lines. Semi-quantitative assay was used to evaluate the quantity of survivin protein and mRNA expression in subtypes of lymphoma. Results： Protein expression of survivin was high and strong in diffuse large B-cell lymphoma （DLBL） （88.6%, 70/79）, Burkitt lymphoma （BL） （100%, 2/2）, and lymphoblastic lymphoma （LBL） （92.3%, 12/13）, while their expression was always lower and weaker in follicular lymphoma （FL） （18.2%）, extranodal marginal zone B-cell lymphoma of mucosaassociated lymphoid tissue （MALT lymphoma） （40.9%） and marginal zone lymphoma （MZL） （33.3%）. There was a significant difference between the higher expression group （DLBL, BL and LBL） and lower one （FL, MZL, and MALT） in the expression of survivin （Chi-square test, X^2=24.77, P〈0.01）. Almost all of Reed-Sternberg cells （R-S cells） in Hodgkin lymphoma （HL） strongly expressed survivin. The protein expression of survivin was positively correlated with mRNA （r=0.6270, P〈0.01）. Conclusion： The expression level of survivin mRNA and protein shows significant difference in subtypes of lymphoma. The expression of survivin mRNA might act as a biomarker to classify the subtypes of lymphoma.

Diagnosis of nervous necrosis virus in orange-spotted grouper,Epinephelus coioides, by a rapid and convenient RT-PCR method

Viral nervous necrosis （VNN） causes high mortality in marine fish, especially in the grouper, worldwide and in China. Since there is no effective vaccine or drug to deal with VNN, early detection and prevention is important to block its outbreak. In this study, a reverse transcription-polymerase chain reaction （RT-PCR） was developed for the rapid, convenient, and sensitive detection of the VNN pathogen, nervous necro- sis virus （NNV）, in the grouper. The whole process was completed within 3.5 h from the RNA extraction to PCR product visualization. The detection limit of this method was 200 copies of NNV RNA standard, which corresponded to 200 copies of virus particles. This RT-PCR method was specific to the NNV detection with no cross-reactivity to other fish viral disease pathogens, such as infectious pancreatic necrosis virus （IPNV）, infectious hematopoietic necrosis virus （IHNV）, spring viraemia of carp virus （SVCV）, epizootic haematopoietic necrosis virus （EHNV）, and large yellow croaker iridovirus （LYC1V）. With this method, the orange-spotted grouper （Epinephelus coioides） fry from hatcheries with or without incidence of the VN- N epidemic in Fujian Province were detected. The results showed that all or 93% of the fry from the two hatcheries with incidence of the epidemic were diagnosed as positive, while 40% or 25% of fry from the t- wo hatcheries without the VNN epidemic were also detected as NNV positive, indicating that this RT-PCR method can be used for rapid, sensitive detection of NNV infection and applied in the VNN epidemic alert.

Expression and functional characterization of platelet-derived growth factor receptor-like gene

AIM:To investigate the role of platelet-derived growth factor receptor-like gene(PDGFRL)in the anti-cancer therapy for colorectal cancers(CRC).METHODS:PDGFRL mRNA and protein levels were measured by reverse transcription-polymerase chain reaction(RT-PCR)and immunohistochemistry in CRC and colorectal normal tissues.PDGFRL prokaryotic expression vector was carried out in Escherichia coli(E.coli),and purified by immobilized metal affinity chromatography.The effect of PDGFRL protein on CRC HCT-116 cells was detected by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide(MTT),clone counting,cell cycle,and wound healing assay.RESULTS:Both RT-PCR and immunohistochemistry showed that the expression of PDGFRL in colorectal normal tissues was higher than in cancer tissues.Recombinant pET22b-PDGFRL prokaryotic expression vector was successfully expressed in E.coli,and the target protein was expressed in the form of inclusion bodies.After purification and refolding,recombinant human PDGFRL(rhPDGFRL)could efficiently inhibit the proliferation and invasion of CRC HCT-116 cells detected by MTT,clone counting and wound healing assay.Moreover,rhPDGFRL arrested HCT-116 cell cycling at the G0/G1 phase.CONCLUSION:PDGFRL is a potential gene for application in the anti-cancer therapy for CRC.

Insulin-like growth factor receptor-1 overexpression is associated with poor response of rectal cancers to radiotherapy

AIM: To explore the potential correlation between insulin-like growth factor receptor-1 (IGF-1R) expression and rectal cancer radiosensitivity.

Expression of huCdc7 in colorectal cancer

AIM:To detect the expression of huCdc7 in colorectal cancer.METHODS:The mRNA and protein expression of huCdc7 in 39 colorectal cancer tissue specimens and matched tumor-adjacent normal colorectal tissue specimens was detected by reverse transcription-polymerase chain reaction and immunohistochemistry,respectively.RESULTS:The relative expression level of huCdc7 mRNA in colorectal cancer was significantly higher than that in tumor-adjacent normal colorectal tissues(0.03675 ± 1.00 vs 0.01199 ± 0.44,P < 0.05).huCdc7-positive cells displayed brown granules in the nucleus.Tumor tissues contained many huCdc7-positive cells,whereas normal colorectal tissues contained very few positive cells.CONCLUSION:huCdc7 may play an important role in the development and progression of colorectal cancer.

In advanced gastric cancer:Prognosis and treatment of patients with positive peritoneal cytology

Positive peritoneal cytology in gastric cancer is classified as M1 disease by the 7thEdition of American Joint Committee on Cancer staging system.With the introduction of laparoscopy and peritoneal washing cytology in the staging of gastric cancer a new category of patients has been identified.These are patients with no macroscopic peritoneal metastases but with peritoneal cytology positive(P0C1).Prognosis and treatment of such patientsrepresent a controversial issue.We evaluate the state of the art of staging system in gastric cancer and discusss tandardisation in staging and treatment procedures.There is still a lack of uniformity in the use of laparoscopy with peritoneal cytology in clinical decision making and in the surgical treatment for gastric cancer.Survival of this patient subset remains poor.Multimodal therapies and new therapeutic strategies are required to improve the survival of these patients.

Silencing the enhancer of zeste homologue 2,Ezh2,represses axon regeneration of dorsal root ganglion neurons

Recovery from injury to the peripheral nervous system is different from that of the central nervous system in that it can lead to gene reprogramming that can induce the expression of a series of regeneration-associated genes.This eventually leads to axonal regeneration of injured neurons.Although some regeneration-related genes have been identified,the regulatory network underlying axon regeneration remains largely unknown.To explore the regulator of axon regeneration,we performed RNA sequencing of lumbar L4 and L5 dorsal root ganglion(DRG)neurons at different time points(0,3,6,12 hours,1,3 and 7 days)after rat sciatic nerve crush.The isolation of neurons was carried out by laser capture microscopy combined with NeuN immunofluorescence staining.We found 1228 differentially expressed genes in the injured sciatic nerve tissue.The hub genes within these differentially expressed genes include Atf3,Jun,Myc,Ngf,Fgf2,Ezh2,Gfap and Il6.We verified that the expression of the enhancer of zeste homologue 2 gene(Ezh2)was up-regulated in DRG neurons after injury,and this up-regulation differed between large-and small-sized dorsal root ganglion neurons.To investigate whether the up-regulation of Ezh2 impacts axonal regeneration,we silenced Ezh2 with siRNA in cultured DRG neurons and found that the growth of the newborn axons was repressed.In our investigation into the regulatory network of Ezh2 by interpretive phenomenal analysis,we found some regulators of Ezh2(including Erk,Il6 and Hif1a)and targets(including Atf3,Cdkn1a and Smad1).Our findings suggest that Ezh2,as a nerve regeneration-related gene,participates in the repair of the injured DRG neurons,and knocking down the Ezh2 in vitro inhibits the axonal growth of DRG neurons.All the experimental procedures approved by the Administration Committee of Experimental Animals of Jiangsu Province of China(approval No.S20191201-201)on March 21,2019.

Methods for the extraction and RNA profiling of exosomes

AIM:To develop protocols for isolation of exosomes and characterization of their RNA content.METHODS:Exosomes were extracted from He La cell culture media and human blood serum using the Total exosome isolation(from cell culture media)reagent,and Total exosome isolation(from serum)reagent respectively.Identity and purity of the exosomes was confirmed by Nanosight?analysis,electron microscopy,and Western blots for CD63 marker.Exosomal RNA cargo was recovered with the Total exosome RNA and protein isolation kit.Finally,RNA was profiled using Bioanalyzer and quantitative reverse transcriptionpolymerase chain reaction(q RT-PCR)methodology.RESULTS:Here we describe a novel approach for robust and scalable isolation of exosomes from cell culture media and serum,with subsequent isolation and analysis of RNA residing within these vesicles.The isolation procedure is completed in a fraction of the time,compared to the current standard protocols utilizing ultracentrifugation,and allows to recover fully intact exosomes in higher yields.Exosomes were found tocontain a very diverse RNA cargo,primarily short sequences 20-200 nt(such as mi RNA and fragments of m RNA),however longer RNA species were detected as well,including full-length 18S and 28S r RNA.CONCLUSION:We have successfully developed a set of reagents and a workflow allowing fast and efficient extraction of exosomes,followed by isolation of RNA and its analysis by q RT-PCR and other techniques.

Significance of combined detection of LunX mRNA and tumor markers in diagnosis of lung carcinoma

Objective：To evaluate the significance of combined detection of LunX mRNA,carcinoembryonic antigen （CEA）,neuron-specific enolase （NSE）,and cytokeratin 21-1 fragment （CYFRA21-1） in clinical diagnosis of lung carcinoma.Methods：Based on the quantitative RT-PCR and chemiluminescence immunoassay,the expression levels of LunX mRNA,CEA,NSE,and CYFRA21-1 in 113 patients with lung carcinoma （case group） and 30 healthy participants （control group） were detected.Meantime,the sensitivity,specificity,and accuracy of the combination detection were also explored.Results：The positive rates of LunX mRNA in peripheral blood and CEA,NSE,and CYFRA21-1 in serum were significandy higher in case group than those in control group （x2=17.295,16.825,19.148,and 17.450; P＜0.05）.There was no statistical significance when positive rate of LunX mRNA was evaluated among different pathological types （x2=0.047,P＞0.05）.The positive rate of LunX mRNA in stage Ⅰ ＋ Ⅱ,Ⅲ,and Ⅳ had a significandy increasing tendency （x2=10.565,32.462,P＜0.05）.The positive rate of CYFRA21-1 was highest in squamous carcinoma （78.5％）,the positive rate of NSE was highest in small cell carcinoma （86.7％）,and the positive rate of CEA wag highest in lung adenocarcinoma （80.4％）.The sensitivity and accuracy of the combination detection were 91.1％ and 88.1％,respectively.Conclusions：The combined detection of LunX mRNA and tumor markers （TMs） including CEA,NSE,and CYFRA21-1 in peripheral blood is helpful to increase the diagnostic accuracy of lmg cancer.Also,it can inform the pathological typing of lung carcinoma.

Infiltration Related miRNAs in Bladder Urothelial Carcinoma

This study aimed to investigate infiltration related microRNAs(miRNAs) in bladder urothelial carcinoma(BUC).Twenty patients with BUC were enrolled and divided into 2 groups according to infiltration or not:infiltrating BUC group(n=12) and non-infiltrating BUC group(n=8).Gene chip was used to detect infiltration related miRNAs in the BUC samples.In other recruited 17 patients with BUC who were divided into infiltrating BUC samples(n=14) and non-infiltrating BUC samples(n=3),and in 4 BUC cell lines(EJ,5637,T24 and BIU-87),the expression of miRNAs was assayed by using reverse transcription-polymerase chain reaction(RT-PCR).In infiltrating BUC group,as compared with non-infiltrating BUC group,there were 7 differentially expressed miRNAs:hsa-miR-29c,hsa-miR-200a,hsa-miR-378,hsa-miR-429,hsa-miR-200c and hsa-miR-141 were up-regulated,while hsa-miR-451 was down-regulated.In the BUC samples,the results of RT-PCR were consistent with those by the miRNA array.In the cancer cell lines,RT-PCR in T24 only revealed the similar expression pattern of miRNAs to that by the miRNA array.It is suggested that infiltration of BUC is related with different expression of miRNAs,which may provide a novel platform for further study on function and action mechanism of miRNAs.