Establishment and characterization of a canine chondrosarcoma cell line:Mango

In the global progress of bone tumor research,established stable and long-lasting transgenic chondrosarcoma(CSA)cell lines are rare,mainly of murine and human origin,while the establishment of canine CSA cell lines has yet to be reported.This study established a canine CSA cell line to facilitate the basic clinical study of canine CSA.Fifty fve cases of canine osteolytic disease were collected,and more than 10 bone tumor samples from dogs with typical clinical signs were used for primary cell culture.A cell line with stable passaging for more than 100 generations and mouse tumorigenic ability was successfully cultured.According to the clinical characteristics of the dog and the histopathological results of the primary tumor,CSA was diagnosed,and the CSA cell line was designated Mango.Immunohistochemical(IHC)results showed that the immunoreactivity of bone gamma-carboxyglutamate protein(BGLAP),secreted protein acidic and rich in cysteine(SPARC),alkaline phosphatase(ALPL),vimentin(VIM)and S100 were positive.However,the immunoreactivity of pan-cytokeratin(PCK),chromogranin A(CGA),and platelet endothelial cell adhesion molecule-1(CD31)was negative.Immunofuorescence(IF)results showed that the protein expressions in the Mango cell line were consistent with the IHC identifcation of the primary tumor.The Mango cell line’s doubling time was 43.92 h,and the cell formation rate exceeded 20%.There were abnormal chromosome numbers,hetero staining with toluidine blue,and certain calcifcation abilities.It could be passaged stably and continuously without changing the cell morphology and characteristics.In vivo,the cells were successfully injected into the nude mice model with a tumorigenic rate of 100%.The immunophenotype of the xenograft tumor was consistent with that of the primary tumor.Therefore,we efectively established a canine CSA cell line.As a promising cell material,this cell line can be used to construct a tumor-bearing model conducive to the subsequent basic research of canine CSA.Moreover,because of its similarity to human CSA,the animal model of CSA is also indispensable for investigating human CSA.

Characterization of the infectivity of an Indonesian Zika virus strain in mammalian cell lines

Objective:To characterize the infection patterns and growth characteristics of the Zika virus(ZIKV)strain JMB-185 from Indonesia in various mammalian cell lines.Methods:ZIKV was grown in human(A549,HEK293,HepG2,Huh7,Jurkat,and THP-1)and non-human mammalian(RAW264.7,Vero,and Vero76)cell lines.Viral replication kinetics were measured using plaque assay,while intra-and extracellular viral RNA concentrations were assessed using RT-PCR.Flow cytometry was used to quantify the infected cells and cell viability was measured using an MTT assay.The ability of ZIKV to infect cell lines was visualized using a fluorescence immunostaining assay.Results:This ZIKV strain preferentially infected the lung,kidney,and liver cell lines A549,HEK293,Huh7,Vero,and Vero76,but not the immune cells Jurkat,RAW264.7,and THP-1.By contrast,the ZIKV showed no sign of infection in HepG2 cells,while maintaining viral titer over 3 days post-infection,with no infection recorded in immunostaining,no increase in viral RNA,and no indication of cell deterioration.Conclusions:The Indonesian ZIKV strain has a similar infection profile as other strains,except for its poor infectivity on HepG2 cells.Information on the growth characteristics of Indonesia ZIKV will help expand our understanding of the biology of ZIKV which will be useful for various applications including antiviral discovery.

GATA binding protein 2 mediated ankyrin repeat domain containing 26 high expression in myeloid-derived cell lines

BACKGROUND Thrombocytopenia 2,an autosomal dominant inherited disease characterized by moderate thrombocytopenia,predisposition to myeloid malignancies and normal platelet size and function,can be caused by 5’-untranslated region(UTR)point mutations in ankyrin repeat domain containing 26(ANKRD26).Runt related transcription factor 1(RUNX1)and friend leukemia integration 1(FLI1)have been identified as negative regulators of ANKRD26.However,the positive regulators of ANKRD26 are still unknown.AIM To prove the positive regulatory effect of GATA binding protein 2(GATA2)on ANKRD26 transcription.METHODS Human induced pluripotent stem cells derived from bone marrow(hiPSC-BM)INTRODUCTION Ankyrin repeat domain containing protein 26(ANKRD26)acts as a regulator of adipogenesis and is involved in the regulation of feeding behavior[1-3].The ANKRD26 gene is located on chromosome 10 and shares regions of homology with the primate-specific gene family POTE.According to the Human Protein Atlas database,the ANKRD26 protein is localized to the Golgi apparatus and vesicles,and its expression can be detected in nearly all human tissues[4].Moreover,UniProt annotation revealed that ANKRD26 is localized in the centrosome and contains coiled-coil domains formed by spectrin helices and ankyrin repeats[5,6].The most common disease related to ANKRD26 is thrombocytopenia 2(THC2),which is a rare autosomal dominant inherited disease characterized by lifelong mild-to-moderate thrombocytopenia and mild bleeding[7-9].Caused by the variants in the 5’-untranslated region(UTR)of ANKRD26,THC2 is defined by a decrease in the number of platelets in circulating blood and results in increased bleeding and decreased clotting ability[8,10].Due to the point mutations that occur in the 5’-UTR of ANKRD26,its negative transcription factors(TFs),Runt related transcription factor 1(RUNX1)and friend leukemia integration 1(FLI1),lose their repression effect[11].The persistent expression of ANKRD26 increases the activity of the mitogen activated protein kinase and extracellular signal regulated kinase 1/2 signaling pathways,which are potentially involved in the regulation of thrombopoietin-dependent signaling and further impair proplatelet formation by megakaryocytes(MKs)[11].However,the positive regulators of ANKRD26,which might be associated with THC2 pathology,are still unknown.

New 4-imino-4H-Chromeno[2,3-d]Pyrimidin-3(5H)-Amine: Synthesis, Cytotoxic Effects on Tumoral Cell Lines and in Silico ADMET Properties

The synthesis of new 4-imino-4H-chromeno[2,3-d]pyrimidin-3(5H)-amine in four steps including one step under microwave dielectric heating is reported. The structural identity of the synthesized compounds was established according to their spectroscopic analysis, such as FT-IR, NMR and mass spectroscopy. These new compounds were tested for their antiproliferative activities on seven representative human tumoral cell lines (Huh7 D12, Caco2, MDA-MB231, MDA-MB468, HCT116, PC3 and MCF7) and also on fibroblasts. Among them, only the compounds 6c showed micromolar cytotoxic activity on tumor cell lines (1.8 50 50 > 25 μM). Finally, in silico ADMET studies ware performed to investigate the possibility of using of the identified compound 6c as potential anti-tumor compound.

First report on establishment and characterization of the extrahepatic cholangiocarcinoma sarcoma cell line CBC2T-2

BACKGROUND Extrahepatic cholangiocarcinoma sarcoma is extremely rare in clinical practice.These cells consist of both epithelial and mesenchymal cells.Patient-derived cell lines that maintain tumor characteristics are valuable tools for studying the molecular mechanisms associated with carcinosarcoma.However,cholangiocarcinoma sarcoma cell lines are not available in cell banks.AIM To establish and characterize a new extrahepatic cholangiocarcinoma sarcoma cell line,namely CBC2T-2.METHODS We conducted a short tandem repeat(STR)test to confirm the identity of the CBC2T-2 cell line.Furthermore,we assessed the migratory and invasive properties of the cells and performed clonogenicity assay to evaluate the ability of individual cells to form colonies.The tumorigenic potential of CBC2T-2 cells was tested in vivo using nonobese diabetic/severe combined immunodeficient(NOD/SCID)mice.The cells were injected subcutaneously and tumor formation was observed.In addition,immunohistochemical analysis was carried out to examine the expression of epithelial marker CK19 and mesenchymal marker vimentin in both CBC2T-2 cells and xenografts.The CBC2T-2 cell line was used to screen the potential therapeutic effects of various clinical agents in patients with cholangiocarcinoma sarcoma.Lastly,whole-exome sequencing was performed to identify genetic alterations and screen for somatic mutations in the CBC2T-2 cell line.RESULTS The STR test showed that there was no cross-contamination and the results were identical to those of the original tissue.The cells showed round or oval-shaped epithelioid cells and mesenchymal cells with spindle-shaped or elongated morphology.The cells exhibited a high proliferation ratio with a doubling time of 47.11 h.This cell line has migratory,invasive,and clonogenic abilities.The chromosomes in the CBC2T-2 cells were polyploidy,with numbers ranging from 69 to 79.The subcutaneous tumorigenic assay confirmed the in vivo tumorigenic ability of CBC2T-2 cells in NOD/SCID mice.CBC2T-2 cells and xenografts were positive for both the epithelial marker,CK19,and the mesenchymal marker,vimentin.These results suggest that CBC2T-2 cells may have both epithelial and mesenchymal characteristics.The cells were also used to screen clinical agents in patients with cholangiocarcinoma sarcoma,and a combination of paclitaxel and gemcitabine was found to be the most effective treatment option.CONCLUSION We established the first human cholangiocarcinoma sarcoma cell line,CBC2T-2,with stable biogenetic traits.This cell line,as a research model,has a high clinical value and would facilitate the understanding of the pathogenesis of cholangiocarcinoma sarcoma.

Establishment,Characterization and Expression Pattern of a Spleen Cell Line,SMSP,Derived from Turbot(Scophthalmus maximus)

A turbot(Scophthalmus maximus)cell line named SMSP was obtained from the spleen.The origin of the cells was identified by morphology,chromosome number and COI gene.The optimal basic medium,serum concentration and growth temperature of the cells were detected.SMSP cell line is mainly composed of fibroblast-like cells.Most of the SMSP cells contained 44 chromosomes,and the sequence of COI gene confirmed that the cells were originated from turbot.The optimal culture conditions were 24℃,DMEM+10%FBS.The cell line had high transfection efficiency for siRNA and plasmid.After stimulation with lipopolysaccharide(LPS)or poly(I:C),the expressions of immune-related genes such as TNF-β,IL-12s,IL-10 and IL-1βwere up-regulated significantly in the early stage(P<0.05).This study will provide a model for exploring immune mechanism of turbot against pathogen in vitro.

Establishment and characterization of a new human ampullary carcinoma cell line,DPC-X1

BACKGROUND An in-depth study of the pathogenesis and biological characteristics of ampullary carcinoma is necessary to identify appropriate treatment strategies. To date, only eight ampullary cancer cell lines have been reported, and a mixed-type ampullary carcinoma cell line has not yet been reported.AIM To establish a stable mixed-type ampullary carcinoma cell line originating from Chinese.METHODS Fresh ampullary cancer tissue samples were used for primary culture and subculture. The cell line was evaluated by cell proliferation assays, clonal formation assays, karyotype analysis, short tandem repeat(STR) analysis and transmission electron microscopy. Drug resistances against oxaliplatin, paclitaxel, gemcitabine and 5-FU were evaluated by cell counting kit-8 assay. Subcutaneous injection 1 × 106 cells to three BALB/c nude mice for xenograft studies. The hematoxylin-eosin staining was used to detect the pathological status of the cell line. The expression of biomarkers cytokeratin 7(CK7), cytokeratin 20(CK20), cytokeratin low molecular weight(CKL), Ki67 and carcinoembryonic antigen(CEA) were determined by immunocytochemistry assay.RESULTS DPC-X1 was continuously cultivated for over a year and stably passaged for more than 80 generations;its population doubling time was 48 h. STR analysis demonstrated that the characteristics of DPC-X1 were highly consistent with those of the patient’s primary tumor. Furthermore, karyotype analysis revealed its abnormal sub-tetraploid karyotype. DPC-X1 could efficiently form organoids in suspension culture. Under the transmission electron microscope, microvilli and pseudopods were observed on the cell surface, and desmosomes were visible between the cells. DPC-X1 cells inoculated into BALB/C nude mice quickly formed transplanted tumors, with a tumor formation rate of 100%. Their pathological characteristics were similar to those of the primary tumor. Moreover, DPC-X1 was sensitive to oxaliplatin and paclitaxel and resistant to gemcitabine and 5-FU. Immunohistochemistry showed that the DPC-X1 cells were strongly positive for CK7, CK20, and CKL;the Ki67 was 50%, and CEA was focally expressed.CONCLUSION Here, we have constructed a mixed-type ampullary carcinoma cell line that can be used as an effective model for studying the pathogenesis of ampullary carcinoma and drug development.

Screening of the Metastasis-Associated Genes by Gene Chip in High Metastatic Human Ovarian Cancer Cell Lines

Affymetrix U133A oligonucleotide microarrays were used to study the differences of gene expressions between high （H） metastatic ovarian cancer cell line, HO-8910PM, and normal ovarian tissues （C）. Bioinformatics was used to identify their chromosomal localizations. A total of 1,237 genes were found to have a difference in expression levels more than eight times. Among them 597 were upregulated [Signal Log Ratio （SLR） ≥3], and 640 genes were downregulated （SLR≤-3）. Except one gene, whose location was unknown, all these genes were randomly distributed on all the chromosomes. However, chromosome 1 contained the most differentially expressed genes （115 genes, 9.3%）, followed by chromosome 2 （94 genes, 7.6%）, chromosome 12 （88 genes, 7.1%）, chromosome 11 （76 genes, 6.1%）, chromosomes X （71 genes, 5.7%）, and chromosomes l7 （69 genes, 5.6%）. These genes were localized on short-arm of chromosome （q）, which had 805 （65.1%） genes, and the short arms of No.13, 14, 15, 21, and 22 chromosomes were the only parts of the chromosomes where the differentially expressed genes were localized. Functional classification showed that most of the genes （306 genes, 24.7%） belonged to the enzymes and their regulator groups. The subsequent group was the nucleic acid binding genes （144 genes, 11.6%）. The rest of the top two groups were signal transduction genes （137 genes, 11.1%） and proteins binding genes （116 genes, 9.4%）. These comprised 56.8% of all the differentially expressed genes. There were also 207 genes whose functions were unknown （16.7 %）. Therefore it was concluded that differentially expressed genes in high metastatic ovarian cancer cell were supposed to be randomly distributed across the genome, but the majority were found on chromosomes 1, 2, 12, 11, 17, and X. Abnormality in four groups of genes, including in enzyme and its regulator, nucleic acid binding, signal transduction and protein binding associated genes, might play important roles in ovarian cancer metastasis. Those genes need to be further studied.

Reversing effect of Tanshinone on malignant phenotypes of human hepatocarcinoma cell line

AIM To study the reversing effect of Chinese drug tanshinone on malignant phenotype of cancer cells.METHODS Human hepatocarcinoma cell line (SMMC-7721) was treated in vitro with 0.5mg/L tanshinone for 4 days, and variation in cell differentiation was detected.RESULTS The morphology of cancer cells was tended toward well differentiation and cell growth was markedly inhibited. BrdU uptake assay and immunohistochemical stain of PCNA showed that the BrdU labeling rate and PCNA positive rate were lower than the controls, but no difference was found statistically as compared with all transretinoic acid. Flow cytometric assay demonstrated that S phase cells decreased and G0/G1 phase cells increased. Expression of c-myc oncogene protein decreased but the c-fos oncogene protein markedly increased.CONCLUSION Tanshinone could reverse the inducing differentiation in human hepatocarcinoma cells (SMMC-7721). It may become a new prospective inducer of cell differentiation to treat cancers.

Transcription factor EGR-1 inhibits growth of hepatocellular carcinoma and esophageal carcinoma cell lines

AIM: The transcription factor EGR-1 (early growth response gene-1) plays an important role in cell growth, differentiation and development. It has identified that EGR-1 has significant transformation suppression activity in some neoplasms, such as fibrosarcoma, breast carcinoma. This experiment was designed to investigate the role of egr-1 in the cancerous process of hepatocellular carcinoma (HCC) and esophageal carcinoma (EC), and then to appraise the effects of EGR-1 on the growth of these tumor cells. METHODS: Firstly, the transcription and expression of egr-1 in HCC and EC, paracancerous tissues and their normal counterpart parts were detected by in situ hybridization and immunohistochemistry, with normal human breast and mouse brain tissues as positive controls. Egr-1 gene was then transfected into HCC (HHCC, SMMC7721) and EC (ECa109) cell lines in which no egr-1 transcription and expression were present. The cell growth speed, FCM cell cycle, plate clone formation and tumorigenicity in nude mice were observed and the controls were the cell lines transfected with vector only. RESULTS: Little or no egr-1 transcription and expression were detected in HCC, EC and normal liver tissues. The expression of egr-1 were found higher in hepatocellular paracancerous tissue (transcription level P=0.000; expression level P=0.143, probably because fewer in number of cases) and dysplastic tissue of esophageal cancer (transcription level P=0.000; expression level P=0.001). The growth rate of egr-1-transfected HHCC (HCC cell line) cells and ECa109 (EC cell line) cells was much slower than that of the controls. The proportion of S phase cell, clone formation and tumorigenicity were significantly lower than these of the controls' (decreased 45.5% in HHCC cells and 34.1% in ECa109 cells; 46.6% and 41.8%; 80.4% and 72.6% respectively). There were no obvious differences between SMMC7721 (HCC) egr-1-transfected cells and the controls with regard to the above items. CONCLUSION: The decreased expression of egr-1 might play a role in the dysregulation of normal growth in the cancerous process of HCC and EC. Egr-1 gene of transfected HHCC and ECa109 cells showed obvious suppression of the cell growth and malignant phenotypes, but no suppression in SMMC7721 (HCC cell line) cells.

The effect of adenovirus expressing wild-type p53 on 5-fluorouracil chemosensitivity is related to p53 status in pancreatic cancer cell lines

AIM:There are conflicting data about p53 function on cellular sensitivity to the cytotoxic action of 5-fluorouracil (5-FU). Therefore the objective of this study was to determine the combined effects of adenovirus-mediated wild-type (wt) p53 gene transfer and 5-FU chemotherapy on pancreatic cancer cells with different p53 gene status. METHODS:Human pancreatic cancer cell lines Capan-1^(p53mut), Capan-2^(p53wt),FAMPAC^(p53mut),PANC1^(p53mut),and rat pancreatic cancer cell lines AS^(p53wt) and DSL6A^(p53null) were used for in vitro studies.Following infection with different ratios of Ad- p53-particles (MOI) in combination with 5-FU,proliferation of tumor cells and apoptosis were quantified by cell proliferation assay (WST-1) and FACS (PI-staining).In addition,DSL6A syngeneic pancreatic tumor cells were inoculated subcutaneously in to Lewis rats for in vivo studies. Tumor size,apoptosis (TUNEL) and survival were determined. RESULTS:Ad-p53 gene transfer combined with 5-FU significantly inhibited tumor cell proliferation and substantially enhanced apoptosis in all four cell lines with an alteration in the p53 gene compared to those two cell lines containing wt-p53.In vivo experiments showed the most effective tumor regression in animals treated with Ad-p53 plus 5-FU.Both in vitro and in vivo analyses revealed that a sublethal dose of Ad-p53 augmented the apoptotic response induced by 5-FU. CONCLUSION:Our results suggest that Ad-p53 may synergistically enhance 5-FU-chemosensitivity most strikingly in pancreatic cancer cells lacking p53 function.These findings illustrate that the anticancer efficacy of this combination treatment is dependent on the p53 gene status of the target tumor cells.

Effect of a nitric oxide synthase inhibitor NG-nitro-L-arginine methyl ester on invasion of human colorectal cancer cell line SL-174T

AIML To investigate the effect and mechanism of action of the nitric oxide synthase （NOS） inhibitor NG-nitro-L-arginine methyl ester （L-NAME） on invasion and metastasis of human colorectal cancer cell line SL-174T. METHODS： Human colorectal cancer cel4 line SL-174T was cultured and treated separately with four different dosages of L-NAME for 72 h, Nitric oxide （NO） production was measured with Griess reagent, The effect of L-NAME on invasion and migration of SL-174T cells were evaluated by using Transwell chambers attached with polycarbonate filters and reconstituted basement membrane （Matrigel）, RT-PCR was performed to determine the mRNA levels of matrix metalloproteinase-2 （MMP-2） and tissue inhibitor metalloproteinase-2 （TIMP-2）,RESULTS： L-NAME could significantly inhibit NO production of SL-174T in a dose-dependent manner. After being treated for 72 h with 0.2, 0.4, 0.8, and 1.0 mmol/L L- NAME, respectively, the ability of the L-NAME treated SL- 174T cells to invade the reconstituted basement membrane decreased significantly （t = 8.056, P〈0.05; t= 14.467, P〈0.01; t= 27.785, P〈0.01; and t= 29.405, P〈0.01, respectively） and the inhibition rates were 10.29%, 19.62%, 34.08%, and 42.23%, respectively. Moreover, L-NAME could inhibit migration of SL-174T cells, and the inhibition rates were 20.76%, 24.95%, 39.43%, and 46. 85% for L-NAME at 0.2, 0.4, 0.8, and 1.0 mmol/L, respectively （t = 15.116, P〈0.01）. In addition, after treatment with L-NAME, expression of MMP-2 mRNA was significantly decreased （t = 71.238, P〈0.01） and that of TIMP-2 mRNA was markedly increased （t = -13.020, P〈0.01）. CONCLUSION： L-NAME exerts anti-invasive and anti- metastatic effects on SL-174T cell line via downregulating MNP-2 mRNA expression and upregulating TIMP-2 mRNA expression.

Establishment and Characterization of a New Cell Line from the Kidney of Spotted Halibut Verasper variegates

A cell line, SHK, was derived from the kidney of spotted halibut Verasper variegates. The cell line was subcultured more than 40 passages in minimum essential medium （MEM） supplemented with fetal bovine serum （FBS） and 10 ng ml4 basic fibroblast growth factor （bFGF）. Cell morphology from primary culture and subculture was observed continuously by microscopy. The SHK cell line consisted predominantly of fibroblast-like cells. The cell line was able to grow between 20℃ and 30℃ with the optimum growth at 24℃ and with a reduced growth between 12℃ and 20℃. The growth rate of the cells increased as the proportion of FBS increased from 10% to 20% at 28℃ with optimum growth at the concentration of 20%. The doubling time of the cells was determined to be 44.8 h. Chromosome analysis revealed that 52% of the SHK cells maintained a normal diploid chromosome number （2n=46）. The cells were successfully transfected with green fluorescent protein （GFP） reporter plasmids and the expression of GFP gene in the cells indicated the possible utility of the cells in gene expression studies. The cells were infected by lymphosystis disease virus （LCDV） and found to be susceptible to the virus in cytopathic effect （CPE） observation. The infection was confirmed by PCR and electron microscopy experiments, which proved the existence of the viral particles in the cytoplasm of the virus-infected cells.

The effect of antisense oligodeoxynucleotides targeting Aurora A kinase on cell proliferation and chemosensitivity to paclitaxel in human lung cancer cell line A549

Objective： Aurora A kinase representing a family of evolutionadly conserved mitotic serine/threonine kinases has been found elevated in human lung adenocarcinoma cell line A549. It is suggested that the overexpression of Aurora A contributes to the carcinogenesis, chromosomal instability （CIN）, and de-differentiation of lung cancers. To address its possibility as a therapeutic target for lung cancer, we employed the antisense oligodeoxynucleotide （ASODN） technique to inhibit Aurora A expression and investigate its effects on tumor growth and cell cycle of A549, as well as the chemosensitivity to paclitaxel. Methods： Aurora AASODN was synthesized and transfected into A549 cells by lipofectAMINE 2000. Aurora A mRNA and protein expression were examined by reverse transcription-polymerase chain reaction （RT-PCR） and Western blot respectively. Cell cycle distribution was observed by flow cytometer. MTT assay was used to evaluate cell inhibition ratio before and after transfection. Results： The proliferation of the A549 cells was inhibited by Aurora A ASODN dose and time dependently. It was also observed that the IC50 of A549 cells after 48 hours＇ treatment of ASODN was about 300 nmol/L and under such circumstances, the Aurora A mRNA and protein expression significantly decreased （P 〈 0.05）, along with the induction of accumulation of cells in S phase and the G2-M transition. Furthermore, cell inhibition ratio of the combination of Aurora AASODN and paclitaxel was higher significantly than paclitaxel （P 〈 0.05） or Aurora AASODN alone （P 〈 0.05）. Conclusion： Inhibition of Aurora A expression can result in the suppression of cell growth and chemosensitizing activity to paclitaxel in human lung cancer cell line A549.

Inhibition of all-trans retinoic acid on MDM2 gene expression in astrocytoma cell line SHG-44

Objective To investigate the impact of all-trans retinoic acid （ATRA） on MDM2 gene expression in astrocytoma cell line SHG-44, and to provide basic data for further research on the progression mechanism and gene therapy of human astrocytoma. Methods The differential expressions of MDM2 gene and protein in SHG-44 cells were detected by cDNA microarray and Western blot, respectively, before and after treatment of ATRA. The expressions of MDM2 protein in WHO grade Ⅱ and grade Ⅳ astrocytomas were determined by immunohistochemical streptavidin-peroxidase method. Some differentially expressed genes were selected randomly for Northern blot analysis. Results The intensity ratio of ATRA-treated to untreated SHG-44 cell was 0.37 in the cDNA microarray, suggesting that the expression of MDM2 gene was down-regulated in SHG-44 cells after treatment with ATRA. Some genes differentially expressed in the microarray were confirmed by Northern blot. Western blot demonstrated that the optical density ratios of MDM2 to β-actin in ATRA-treated and untreated SHG-44 were 14.02±0.35 and 21.40±0.58 （t = 24.728, P = 0.000）, respectively, suggesting that the expression of MDM2 protein was inhibited in ATRA-treated SHG-44 cells. Moreover, the percentages of MDM2-positive protein were 24.00% （6/25） and 56.52% （13/23） （x^2 = 5.298, P = 0.021） in WHO grade Ⅱ and grade Ⅳ astrocytomas, respectively, suggesting that the expression of MDM2 protein may increase along with the elevation of astrocytoma malignancy. Conclusion ATRA can inhibit MDM2 gene expression in SHG-44 cells, and MDM2 is related to astrocytoma progression.

The Establishment and Characterization of a Continuous Cell Line of Mouse Cervical Carcinoma

OBJECTIVE To establish a murine uterine cervical cancer cell line and to define its biological characters. METHODS Transplanted tumor tissue was used for in vitro primary culture of U14 cervical carcinoma cells. After 20 passages, we examined its morphology, chromosomes, tumorigenicity and produced a growth curve. CK was detected by immunohistochemistry, the cell cycle determined by flow cytometry and the metastatic potential assessed in 615 and C57BL/c mice. We also transfected the cells with the pEGFP-N1 plasmid. RESULTS A newly established murine cell line was passaged 50 times over a period of 10 months. The cells grow as a partially suspended culture, and are immunohistochemically CK（＋）. The cell line is characterized by a hypotetraploid karyotype, a chromosomal number of 64-68 and a doubling time of 21.8 h. Exponential growth occurs by the third and forth day of culture. Cell cycle analysis showed G1 34%, G2 26%, and 40% in the S phase. The tumorigenicity was 100% upon implantation. No mycoplasma contamination was detected. A monoclonal continuous U14-GFP cell strain which was 100% GFP （＋） was also produced. CONCLUSION We successfully established a new murine cervical U14 carcinoma cell line and an U14-GFP monoclonal strain. These cell lines are ideal for combined in vivo and in vitro tumor research.

Cytotoxic Effect of Chitosan Based Nanocomposite Synthesized by Radiation： In Vitro Liver and Breast Cancer Cell Line

A silver nanoparticle （AgNP） is likely to provide an attractive object for combining a variety of biochemical properties with great therapeutic potential by using radiation. The present study explores the ICs0 value of chitosan-poly （vinyl alcohol） hydrogel （Cs/PVA） and Ag-doped chitosan-poly （vinyl alcohol） （Cs/PVA/Ag） nanocomposite in view of their anticancer application. The aim was to develop （Cs/PVA） based hydrogel synthesized by gamma radiation which could behave both as a nanoreactor for Ag nanoparticle with promising anticancer applications. The （Cs/PVA/Ag） nanocomposite was confirmed by FTIR （Fourier transform infrared） spectroscopy, XRD （X-ray diffraction） and EDX （energy dispersive X-ray） analysis. The anti-cancer activity of the prepared nanocomposites was demonstrated in human liver cancer cell line （HEPG2） and breast cancer cell lines （MCF7）. It has significant effects against human liver cancer cell line HEPG2 compared to breast cancer cell line MCF7. Further quantitative analysis on the molecular and protein levels is still required to confirm the impact of chitosan on genotoxic effect before reaching a final conclusion and starting its biomedical application.

INDEPENDENT AND SYNERGIC INHIBITION OF VERAPAMIL AND ELECTRIC BEAM RADIATION ON CLONOGENIC GROWTH IN K562 AND K562/ADM CELL LINES IN VITRO

It was first reported here that verupamil(VP) and electric beam radiation(EBR) were capable of inhibiting,independently or synergically,clonogenic growth in two kinds of K562 cell lines, adriamycin(ADM)-sensitive and ADM-resistant(K562/S and K562/ADM).Results showed that clonogenic rate(CGR) decreased by 3%-99.9% in the prasence of dependent dose-ADM(3.8μg/ml) in K562/ADM cell lines,while treated with 0.5μM-6μM of VP.VP was capable of potentiating radiosensitivity in K562/S and K562/ADM cell lines,whether before or after exposure of them to electric beam radiation,and significantly reduced CGR in these kinds of cell lines(P<0.01).

Differential Proteomics in Malignant and Normal Liver Cell Lines

Objective： To detect differential protein expression in malignant and normal liver cell lines in vitro using the SELDI ProteinChip platform, for investigating the pathogenesis of liver cancer. Methods： Two cell lines, human normal liver cell line L02 and hepatoma cell line SMMC-7721 were cultured routinely, harvested in good condition and lysed. After quantification, the supernatant of the lysate was tested by IMAC3 （Immobilized Mental Affinity Capture） and WCX2 （Weak Cation Exchange） chips on the SELDI-TOF-MS ProteinChip reader. Results： Protein expression differed between the malignant and normal liver cell lines. A total of 20 differentially expressed proteins were found, among which, 7 were captured by the IMAC3 chip and 14 by the WCX2 chip. Peaks at 5,419, 7,979 and 11,265 Da were higher and at 8,103, 8,492, 10,160 and 11,304 Da lower in SMMC-7721 cells by the IMAC3 chip; peaks at 7,517, 7,945 and 7,979 Da were higher and at 5,061, 5,551, 5,818, 7,439, 9,401,10,100, 10,312, 11,621, 11,662, 11,830 and 12,772 Da lower in SMMC-7721 cells by the WCX2 chip. Interestingly, both chips captured the 7,979 Da peak. In addition, the 11,081 Da peak corresponded precisely with the molecular mass of the calcium binding protein S100A10, which may participate in the formation of liver cancer in association with p36. Conclusion： Detecting differential protein expression in malignant and normal liver cell lines using the SELDI ProteinChip platform was simple, sensitive and repeatable. The results we obtained can serve as a basis for investigating the pathogenesis of liver cancer and aid the discovery of new therapeutic targets.

Effect of DRB on the Biological Characteristics of Human Laryngeal Carcinoma Hep-2 Cell Line

In order to study the effect of 5, 6-Dichloro-l-13-D-ribofuranosyl-benzimidazole （DRB） on the biological characteristics of human laryngeal carcinoma Hep-2 cell line in vitro, Hep-2 cells cultured in vitro were treated with different concentrations of DRB. Changes in cell proliferation, apoptotic rate and invasiveness were detected by MTT assay, flow cytometry （FCM） and matrigel in vitro invasion assay, respectively. It was found that DRB inhibited the proliferation of Hep-2 cells in a dose- and time-dependent manner. After being treated with 0, 10, 20, 40, 80 μmmol/L DRB for 24 h, the apoptotic rate in Hep-2 cells was （0.68±0.19）%, （1.95±0.12）%, （8.51±0.26）%, （11.26±0.17）% and （14.99±0.32）%, respectively. The matrigel in vitro invasion assay revealed that DRB began to inhibit the invasion of Hep-2 cells at the concentration of 5 μmmol/L, and with the increase of DRB concentration, the inhibitory effect was enhanced. It was suggested that DRB could influence the essential biological characteristics of Hep-2 cells, inhibit Hep-2 cells proliferation, reduce invasive ability and induce apoptosis of Hep-2 cells.