BACKGROUND: Thyroid cancer stem cells are essential to the recurrence and metastasis of thyroid carcinoma. Leukemia inhibitory factor receptor (LIFR) shows a downward trend in a variety of malignant tumors, and its overexpression can inhibit the recurrence and metastasis of malignant tumors. OBJECTIVE:To explore the effect of LIFR on the stemness maintenance and lung metastasis of thyroid cancer stem cells in vivo. METHODS: Primary thyroid cancer cells TCLM were isolated from the lung metastases of a metastatic thyroid cancer patient. Serum-free suspension culture was used to form tumor cell balls. Flow cytometry was used to screen CD133+phenotype of metastatic thyroid cancer stem cell subpopulation TCLM-S. The overexpressed recombinant lentiviral plasmid containing LIFR and its negative control containing the empty plasmid were infected into thyroid cancer stem cells TCLM-S at the ratio of virus/cell number=20, and screened with 2.0 mg/L puromycin to construct TCLM-SLIFRand TCLM-Scontrolstem cells which stably expressed LIFR and its control. Real-time quantitative PCR (qRT-PCR) was used to detect the expression of LIFR in TCLM-SLIFRand TCLM-Scontrolstem cells. Flow cytometry was used to detect the percentage of CD133+phenotype cell subsets, western blot assay was used to detect the expression of tumor stemness related factors SOX2, Oct4, Nanog and tumor invasion and metastasis related proteins E-cadherin, matrix metalloproteinase (MMP)-2, MMP-7 in TCLM-SLIFRand TCLM-Scontrol stem cells. TCLM-SLIFRand TCLM-Scontrolstem cells were respectively injected into BALB/c nude mice by tail vein, and the lung metastasis model of thyroid cancer stem cells was constructed. The effect of LIFR overexpression on lung metastasis was observed. RESULTS AND CONCLUSION: Compared with TCLM-Scontrolcells, the expression of LIFR in TCLM-SLIFRcells was significantly increased, the proportion of CD133+phenotype stem cell subsets was significantly decreased, the expression of SOX2, Oct4 and Nanog were significantly decreased, the expression of E-cadherin was significantly increased, and the expression of MMP-2 and MMP-7 was significantly decreased. Moreover, the number of lung metastasis in nude mice given TCLM-SLIFRcells was significantly decreased as compared with those given TCLM-Scontrol cells.To conclude,LIFR overexpression can decrease the stemness and ability of lung metastasis in vivo.

OBJECTIVEThe co-culture model of Syrian hamster embryo (SHE) normal (primary cell) and preneoplastic cells mimicking in vivo status was established and used to study the chemopreventive effects of epigallocatechin-3-Gallate (EGCG) on cell growth, proliferation, apoptosis and regulated genes expression of SHE preneoplastic cells and discussed on the mechanism of EGCG's chemopreventive effect of carcinogenesis.

METHODSThe SHE cell preneoplastic and normal cells were cultured on the plates with 1:10,000, 1:1000, 1:100, 1:10 rates for 7 days, and the co-culture model was established. The different concentration of EGCG (0, 0.5, 1, 5, 10, 50 micromol/L) were used to treat the cells and the SHE cells growth assay, in situ cell apoptosis assay, in situ cell proliferation assay and microarray assay were used to determined the growth, apoptosis and proliferation of SHE preneoplastic cells.

RESULTSThe co-culture model of SHE cells with the 1:100 rate between SHE preneoplastic cells and normal cells was established. 0.5, 1, 5, 10 micromol/L EGCG increased the colony growth and proliferation of SHE normal cells. In the coculture model of SHE cells with 1:200 rate, compared the the control group, 5, 10 micromol/L EGCG suppressed the growth of different size of SHE preneoplastic cells clone. The DNA proliferation index and apoptosis index in the control group were 39.3% and 6.5%, respectively. After treatment of 5, 10 micromol/L EGCG, the proliferation index were decreased to 25.6% and 24.8%, and the apoptosis index were increased to 12.65% and 14.5%. EGCG suppressed the growth and proliferation of SHE preneoplastic cells in co-culture model and increased its apoptosis. The pathway of cell apoptosis was regulated through the P53, NF-kappaB, bcl-2 signal pathway, and the pathway of cell proliferation was regulated through the growth arrest at G1/S phase of cell cycle.

CONCLUSIONThe selective regulation of EGCG to normal and preneoplastic cells, the interaction of EGCG, SHE normal cells and SHE preneoplastic cells in co-culture model indicate that the suppression of proliferation and induction of apoptosis of preneoplastic cells by EGCG might be the mechanism of green tea' s chemopreventive effects to tumorigenicity.

Animals ; Apoptosis ; drug effects ; CHO Cells ; Catechin ; analogs & derivatives ; pharmacology ; Cell Division ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cricetinae ; Cricetulus ; Female ; Precancerous Conditions ; Pregnancy ; Tea ; chemistry

E.coli single-stranded DNA-binding protein (SSB) plays an important role in replication, recombination and repair of DNA and is thus crucial for the survival of the bacteria.We described a high expression and efficient purification scheme and kinetic assay of interaction with its substrate, single-stranded DNA (ssDNA). A ssb gene (537 bp) for encoding SSB was obtained by PCR amplification from E.coli K-12 genome. The expression vector of the fusion protein SSB was constructed by attaching ssb gene to pQE30. SSB fusion protein was expressed in M15 E.coli strain induced by IPTG. SDS-PAGE analysis revealed that the expected protein with a molecular weight 20.6kDa was soluble and amounted to about 30% of the total bacterial protein. SSB protein was purified by immobilized metal (Ni2+) chelation affinity chromatography and the purity was about 90%. The resulting SSB protein was a correctly folded tetramer analyzed by gel filtration. It could bind ssDNA with equilibrium dissociation constant (KD) of 4.79×10-7 mol/L as determined by surface plasmon resonance.

Single-Strand Conformation Polymorphism(SSCP) is an effect method for investigating environment microbial genetic polymorphism, with its characterization of rapidness, simplicity, and sensitivity. However, many factors can influence the results of SSCP in the analysis of complex environment samples, and its optimization is highly needed. In this paper, optimal PCR-SSCP conditions were discussed based on PAGE concentration, formamide deionized in denaturing loading buffer, electrophoresis time and temperature. The resluts showed that the optimal conditions were as follows: 16S rDNA V1~V3 was selected as the targeted gene, the ratio of acrylamide to N, N-dimethylacrylamide in 12% polyacrylamide gel electrophoresis(PAGE)gel was 49:1, the ratio of formamide deionized in denaturing loading buffer was 1:3, running the SSCP gel at 300 V for 18 h (under 4 ℃). Aside from this, the validations using samples from a simultaneous desulfurification and denitrification bioreactor were conducted under this optimal conditions.

Purpose To investigate the clinicopathologic characteristics, diagnosis, differential diagnosis and prognosis of malignant solitary fibrous tumor/hemangiopericytoma ( SFT/HPC). Methods Sixteen cases of intracranial malignant SFT/HPC were retrospectively studied. The clinical data, imaging features, histopathological and immunohistochemical characteris-tics were analyzed. Results The 8 male and 8 female patients were between 31 and 71 years of age ( mean 51). The median age was 51 years (range, 31-71 years). 16 malignant SFT/HPC cases were originated from intracalvarium. The imaging features showed intracranial neoplasms with relatively clear surrounding boundaries. Microscopically spindle shaped cells were hypercel-lular, and exhibited≥5 mitoses per 10 HPF. Cytological atypia was mild. The clinicopathologic characteristics included pattern-less growth pattern, storiform or fascicular growth pattern, solita-ry fibrous tumor-like regions and hemangiopericytoma-like re-gions. Tnere were 2 cases with abundant papillary structure and 2 with sarcomatous structure, 2 with focal necrosis, 2 with inva-ded cerebral tissues, and 10 with invaded meninges. Immuno-histochemically, 93. 75% ( 15/16 ) cases were positive for STAT6, with 15/16 showing diffuse staining. 87. 5% (14/16) cases were positive for CD34, with 37. 5% (6/16) showing dif-fuse staining. 81. 25% (13/16) cases were positive for BCL-2. 68. 75% (11/16) cases were positive for CD99. The Ki-67 in-dex ranged from 5% to 40% . Sixteen patients were followed up for 1-64 months, and 7 patients ( 43. 75% ) had recurrences. Conclusion Malignant SFT/HPC shares malignant behaviours. STAT6 is a specific marker for the diagnosis of this tumor. The prognosis of malignant SFT/HPC is related to the extent of tumor excision and long-term follow-up.

Purpose: Gastric cancer (GC) is the second most lethal cancer globally and is associated with poor prognosis. Fatty acid-binding proteins (FABPs) can regulate biological properties of carcinoma cells. FABP5 is overexpressed in many types of cancers; however, the role and mechanisms of action of FABP5 in GC remain unclear. In this study, we aimed to evaluate the clinical and biological functions of FABP5 in GC. Materials and Methods: We assessed FABP5 expression using immunohistochemical analysis in 79 patients with GC and evaluated its biological functions following in vitro and in vivo ectopic expression. FABP5 targets relevant to GC progression were determined using RNA sequencing (RNA-seq). Results: Elevated FABP5 expression was closely associated with poor outcomes, and ectopic expression of FABP5 promoted proliferation, invasion, migration, and carcinogenicity of GC cells, thus suggesting its potential tumor-promoting role in GC. Additionally, RNA-seq analysis indicated that FABP5 activates immune-related pathways, including cytokinecytokine receptor interaction pathways, interleukin-17 signaling, and tumor necrosis factor signaling, suggesting an important rationale for the possible development of therapies that combine FABP5-targeted drugs with immunotherapeutics. Conclusions These findings highlight the biological mechanisms and clinical implications of FABP5 in GC and suggest its potential as an adverse prognostic factor and/or therapeutic target.

Adult ; Aged ; Aged, 80 and over ; Esophageal and Gastric Varices ; complications ; Female ; Gastrointestinal Hemorrhage ; etiology ; Humans ; Logistic Models ; Male ; Middle Aged ; Young Adult

OBJECTIVETo study the prevalence of severe acute respiratory syndrome coronavirus (SARS-CoV) like virus in animals at a live animal market of Guanzhou in 2004 before and after culling of wild animal action taken by the local authority, in order to predict the re-emerging of SARS from animal originals in this region.

METHODSAnimals at live animal market were sampled for rectal and throat swabs in triplicate. A single step realtime reverse transcription-polymerase chain reaction (RT-PCR) diagnostic kit was performed for screening SARS-CoV like virus, the manual nested RT- PCR and DNA sequencing were performed for confirmation. Only specimens which tested positive for both of the N and P genes by nested RT-PCR were scored as positive.

RESULTSIn 31 animals sampled in January 5 2004 before culling of wild animals at Guangdong Province, including 20 cats (Felis catus), 5 red fox (Vulpes vulpes) and 6 Lesser rice field rats (Rattus losea), 8 (25.8%) animals were tested positive for SARS-CoV like virus by RT-PCR methods, of which 4 cats, 3 red fox and one Lesser rice field rats were included. However, two weeks after culling of animals and disinfection of the market were implemented, in 119 animals sampled in January 20 2004, including 6 rabbits (Oryctolagus cuniculus), 13 cats, 46 red jungle fowl (Gallus gallus), 13 spotbill duck (Anas platyrhynchos), 10 greylag goose (Anser anser), 31 Chinese francolin (Franclinus pintadeanus), only rectal swab from one greylag goose was tested positive for SARS-CoV like virus. Furthermore, in 102 animals that including 14 greylag gooses, 3 cats, 5 rabbits, 9 spotbill duck (Anaspoecilorhyncha), 2 Chinese francolin (Franclinus pintadeanus), 8 common pheasant (Phasianus colchicus), 6 pigeons, 9 Chinese muntjac (Muntiacus reevesi), 19 wild boar (Sus scrofa), 16 Lesser rice field rats, 5 dogs, 1 mink (Mustela vison), 3 goats, 2 green peafowl (Pavo muticus) sampled in April, May, June, July, August and November, only rectal swab from one pig was tested positive. However, of 12 and 10 palm civets sampled in November and December including five of which had been at the live animals market for 2 days, none of them was tested positive.

CONCLUSIONThis findings revealed that animals being sampled in April, May, June, July, August and November of 2004, only one rectal swab from a pig was tested positive as SARS-CoV like virus, much lower than the results from the previous year, suggesting that the possibility of re-emerging of human infection from animal origins is low for the winter of 2004-2005.

Animals ; Animals, Wild ; virology ; China ; DNA, Viral ; analysis ; Felidae ; virology ; Reverse Transcriptase Polymerase Chain Reaction ; SARS Virus ; isolation & purification

Objective:To determine the prevalence of facility-based HIV testing and its associated factors among men who have sex with men （MSM） in Shanghai. Methods:From June 2018 to December 2020， MSM were recruited by a community organization “Shanghai CSW&MSM Center （SCMC）”. A total of 3 251 MSM were included as follows： being 18 years old and above， being HIV-negative or with unknown HIV status， living in Shanghai， had homosexual behavior in the past year， and completed informed consent. Using a self-designed questionnaire， we performed an online survey powered by www.wjx.cn to collect information on demographics， sexual behavior， and facility-based HIV testing. A total of 3 240 valid questionnaires were collected. Univariate and multivariate logistic regression were used to determine the factors associated with facility-based HIV testing. Results:A total of 3 240 MSM participated in the study with mean age of （29.7±6.2） years .The prevalence of facility-based HIV testing was 63.2% （2 049/3 240）， Multivariate logistic regression showed that the participants with a college degree or above were less likely to have facility-based HIV testing（OR=0.73，P=0.008）， compared to those with lower educational background. The proportion of the MSM who sought sexual partners through the internet received facility-based testing was 68.7%. Compared to the participants with the sexual role being 0 （only be penetrated）， those being 0.5 （both penetrated and be penetrated） and 1 （only penetrated） were both more likely to have the HIV testing （both P<0.05）. Those who used condoms during the last homosexual behavior were more likely to be tested than those who did not （OR=1.39， P=0.001）. Those who had been diagnosed with sexually transmitted diseases were more likely to be tested than those who did not （OR=2.05， P<0.001）. The participants who had used HIV self-testing kits in the past were more likely to be tested than those who did not （OR=2.31， P<0.001）. Conclusion:MSM in Shanghai have lower utilization of facility-based HIV testing， which may be improved by strengthening the advocacy of facility-based HIV testing services through the internet and peer education， and innovating service models.