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ABSTRACT: ObjectiveTo construct tree models for nasopharyngeal carcinoma (MPC) and colorectal carcinoma (CC) and explore the oncogeneic process
of NPC and CC.
MethodsBased on the software that Desper et al. developed, tree models were constructed for CC from the comparative genomic hybridization
(CGH) data of 118 CC patients and for NPC from the CGH data of 140 southern Chinese patients, respectively.
ResultsTree models for CC suggested that loss of 18q and gain of 20q were important early events in colorectal carcinogenesis. As
changes in - 18q occurred prior to those in —17p, a cause-effect relationship might exist between them. Tree models for NPC
suggested that loss of 3p was an important early event in nasopharyngeal carcinogenesis, and deletion of 11q. 14q. 16q and
9p were also nonrandom genetic events in carcinogenesis. suggesting that there might be tumor -associated genes existing on
these chromosome arms. The tree model also indicated the existence of oncogenes on the short arm of chromosome 12.
ConclusionConstructing tree models based on the CGH data to demonstrate the initiation and progression of NPC might help elucidate its
multigene, multistep and muitipathway development. It may provide valuable clues to explore the mechanism of tumorigenesis.
Chinese Journal of Clinical Oncology 04/2012; 1(3):196-201.
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ABSTRACT: Allelic loss of chromosome 3p, including the 3p21.3 region, is found in 95-100% of primary nasopharyngeal carcinoma (NPC) biopsies, suggesting that this region should harbor some tumor suppressor genes (TSGs) closely related to NPC development. Several TSGs located at 3p21.3, such as RASSF1A, LTF and BLU, have been demonstrated to be involved in NPC development. LARS2 (leucyl-tRNA synthetase 2, mitochondrial) is another gene located in the chromosome 3 common eliminated region-1 (C3CER1) at 3p21.3. In this study, we focussed on the epigenetic and genetic alterations of LARS2 in NPC. The mRNA expression of LARS2 was detected in 36 NPC and 8 chronic nasopharyngitis (NP) tissues by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and real-time RT-PCR. Subsequently, the mutation, allelic loss, and methylation status of LARS2 were analysed by polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP), homozygous deletion (HD) analysis and methylation-specific polymerase chain reaction in primary NPC tissues. No expression or downregulation of LARS2 was observed in 78% of primary NPC tissues. No mutations, assessed by PCR-SSCP and DNA sequencing, were found in the promoter region and exon 1 of LARS2 in NPC tissues, whereas HD was detected in 28% of NPC specimens at the LARS2 locus. In addition, hypermethylation of LARS2 was found in 64% of NPC samples but only in 12.5% of NP biopsies. Our data indicate that inactivation of LARS2 by both genetic and epigenetic mechanisms may be a common and important event in the carcinogenesis of NPC.
Acta Biochimica et Biophysica Sinica 02/2009; 41(1):54-62. · 1.38 Impact Factor
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ABSTRACT: Cross-linked polyacrylic resin supported-cobalt (II) catalyst was successfully employed in controlled/“living” radical polymerization
of various monomers including n-butyl acrylate (BA), ethyl methacrylate (EMA) and styrene (St). Well-defined polymers with predetermined molecular weight
and relatively narrow molecular weight distribution were synthesized. After polymerization, the supported cobalt (II) catalyst
was easily and effectively removed from the polymerization system by simple centrifugation and very pure polymer products
were obtained (Co residue <0.1ppm). Using the obtained polymers as macroinitiators, polymerization of methyl methacrylate
(MMA) and fluorinated methacrylate ether 2-[(perfluorononenyl)oxyl] ethyl methacrylate (FNEMA) were performed, respectively.
Well-defined and pure diblock copolymers PBA-b-PMMA, PS-b-PMMA and PS-b-PFNEMA were synthesized.
Polymer Bulletin 01/2009; 62(2):151-166. · 1.53 Impact Factor
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ABSTRACT: Deleted in liver cancer-1 (DLC-1), encoding a Rho GTPase-activating protein (GAP), is considered as a promising candidate tumor suppressor gene in nasopharyngeal carcinoma (NPC). The single-nucleotide polymorphism (SNP) -29A/T upstream of ATG start codon was found when gene mutation profile of DLC-1 in NPC was analyzed. To evaluate the correlation between SNP -29A/T in the promoter region of DLC-1 gene and risk of NPC, a total of 521 samples from a Chinese population, including 320 healthy individuals and 201 NPC patients, were collected for SNP analysis by PCR-single-strand conformation polymorphism and sequencing. The differences in allele and genotype frequencies between NPC patients and controls were tested using logistic regression statistical method. No significant differences were found in allele or genotype frequencies between NPC patients and controls or among different NPC clinical stages. Hence, our data indicate that the SNP -29A/T of DLC-1 gene is not associated with NPC susceptibility.
Genetic Testing 09/2008; 12(3):345-9. · 1.17 Impact Factor
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Journal of Polymer Science Part A Polymer Chemistry 12/2007; 46(4):1416 - 1426. · 3.92 Impact Factor
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ABSTRACT: Perfluorosulfonated ionomer (PFSI) was synthesized and PFSI membranes were prepared via a solution-cast method and annealed at different temperatures from 150 to 230°C. The annealing effect on water content, proton conductivity, and methanol permeability were reported and discussed. X-ray diffraction and small angle X-ray scattering were used to test the structure of the membranes. It was found that annealing increased the proton conductivity of the membranes because heat-treatment helped to free the sulfonic groups that were buried in the polymer segments and form more organized ionic clusters. Water content and methanol permeability of the annealed membranes decreased with increasing annealing temperature. Simultaneously, annealing induced more compact chain packing structure, which eventually affected the transport of the proton and methanol through these ionomer membranes. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Journal of Applied Polymer Science 09/2007; 107(1):396 - 402. · 1.29 Impact Factor
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ABSTRACT: To explore the expression and the role of PTX1 located at the amplified 12p12-p11 region in nasopharyngeal carcinoma (NPC).
Semi-quantitative RT-PCR and real-time RT-PCR were applied to detect the expression level of PTX1 in 36 NPC and 8 chronic nasopharyngitis (NP) biopsies. RNAi vector targeting PTX1 was constructed and transfected into NPC cell line 6-10B. The RNAi effect was determined by detecting the expression level of PTX1 in transfected 6-10B cell line. Finally, the cell biological characteristics were compared between transfected 6-10B and parental 6-10B by analyzing the cell cycle distribution and apoptosis status using flow cytometry.
RT-PCR and real-time RT-PCR revealed that PTX1 gene was over-expressed in NPC tissues (P<0.05). PTX1 expression was suppressed in NPC cell line 6-10B by approximately 65% by RNAi, confirmed by RT-PCR. The depletion of PTX1 could effectively block the proliferation and induce the apoptosis of NPC cells.
Blocking the expression of PTX1 on mRNA level changed the characterization of NPC cell line 6-10B by RNAi, suggesting that PTX1 identified in the amplified 12p12-p11 region may be involved in the genesis and development of NPC via promoting the cell proliferation and inhibiting the cell apoptosis.
Zhong nan da xue xue bao. Yi xue ban = Journal of Central South University. Medical sciences 05/2007; 32(2):235-40.
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ABSTRACT: Nasopharyngeal carcinoma (NPC) is a malignancy that is prevalent among populations from Southeast Asia. The carcinogenesis of NPC is thought to be a multistep process involving several genetic changes. Our previous study based on distance and branching-tree models for NPC carcinogenesis indicated +12p11-p12 was an early event and should play an important role in NPC development. To understand the role of +12p11-p12 as the tree model predicted and evaluate which gene located at 12p11-p12 might be involved in NPC development, semiquantitative RT-PCR was applied to examine the expression status of 18 genes selected from 12p11-p12 in 36 NPC and 8 normal nasopharynx (NP) biopsies. The results revealed that BCAT1, KCNJ8, PTX1, and KRAS2 genes were overexpressed in NPC tissues and BCAT1 was of particular interest based on its function reported in other tumors. To further elucidate the function of BCAT1 gene in NPC, BCAT1 expression was specifically suppressed in 5-8F NPC cell line by RNA interference (RNAi), confirmed by RT-PCR and Western blotting. As expected, the depletion of BCAT1 could effectively block the proliferation of NPC cells. The BCAT1 identified in the amplified 12p11-p12 region may play a certain role in NPC development.
Oncology Research Featuring Preclinical and Clinical Cancer Therapeutics 02/2007; 16(9):405-13. · 1.30 Impact Factor
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Journal of Polymer Science Part A Polymer Chemistry 04/2006; 44(12):3853 - 3858. · 3.92 Impact Factor
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ABSTRACT: Well-defined poly(vinyl acetate-b-methyl methacrylate) block copolymers were successfully synthesized by the atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) in p-xylene with CuBr as a catalyst, 2,2′-bipyridine as a ligand, and trichloromethyl-end-grouped poly(vinyl acetate) (PVAc–CCl3) as a macroinitiator that was prepared via the telomerization of vinyl acetate with chloroform as a telogen. The block copolymers were characterized with gel permeation chromatography, Fourier transform infrared, and 1H-NMR. The effects of the solvent and temperature on ATRP of MMA were studied. The control over a large range of molecular weights was investigated with a high [MMA]/[PVAc–CCl3] ratio for potential industry applications. In addition, the mechanism of the polymerization was discussed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1089–1094, 2006
Journal of Applied Polymer Science 04/2006; 101(2):1089 - 1094. · 1.29 Impact Factor
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ABSTRACT: To design and clone all known and predicted coding genes of Epstein-Barr virus (EBV) as the cDNA probes for preparing the microarray for EBV detection, thereby to facilitate further investigation of the pathogenetic role of EBV.
Oligo 6.0 software, BLAST program and Primer Premier 5 software were employed to design and screen the cDNA probes of the whole EBV genome, whose length ranged from 300 to 600 mer each with high specificity. These cDNA probes obtained through PCR and reverse transcriptase (RT)-PCR amplification from the genomic DNA and RNA of B95-8 cells and nasopharyngeal carcinoma (NPC) tissue were cloned into T/A clone vector, followed by identification of these probes by sequencing analysis.
A total of 85 gene fragments (BWRF1 gene-contained 7 repeats of open reading frames) coding for proteins and 2 EBERs in EBV genome were successfully cloned, not including LF1 and LF3 genes that did not exist in EBV genome of B95-8 cells, which provides the basis for preparing microarray to explore the role of EBV genome in its related diseases.
Di 1 jun yi da xue xue bao = Academic journal of the first medical college of PLA 04/2005; 25(3):246-50.
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ABSTRACT: To study the gene expression profile of human polymeric immunoglobulin receptor gene (hpIgR)-transfected mouse nasopharyngeal epithelial cells transformed with n, n'-dinitrosoperazine (TMNE) before and after EBV infection using cDNA array and investigate the role of Epstein-Barr virus (EBV) infection in the tumorigenesis of nasopharyngeal carcinoma (NPC).
The total RNAs of hpIgR-transfected TMNE cells before and after EBV infection were extracted, reversely transcribed, and labeled with alpha -(32)P-dATP. The cDNA probes were hybridized to the Atlas mouse cancer array 1.2, and the signals analyzed by AtlasImage software.
Twenty-five genes differentially expressed in cells before and after EBV infection, including 23 up-regulated genes and 2 down-regulated genes.
The gene expression profile of hpIgR-transfected TMNE cells may change after EBV infection, suggesting that these genes are probably involved in the tumorigenesis and progression of NPC.
Di 1 jun yi da xue xue bao = Academic journal of the first medical college of PLA 10/2004; 24(9):1001-5.
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ABSTRACT: To construct tree models for nasopharyngeal carcinoma (NPC)and explore the oncogenesis process of NPC.
Based on the software which Desper et al developed, tree models were constructed for colorectal carcinoma (CC) from the comparative genomic hybridization (CGH) data of 118 CC patients and for NPC from the CGH data of 140 southern Chinese patients, respectively.
Tree models for CC suggested that changes in -18q and +20q were important early events in colorectal carcinogenesis. As changes in -18q occurred prior to those in -17p, there might be some cause-effect relationship. Tree models for NPC suggested that change in -3p was an important early event in nasopharyngeal carcinogenesis, and those in -11q, -14q, -16q, -9p were also non-random genetic events in carcinogenesis, suggesting that there might be tumor-associated genes existing on these chromosome arms. The tree model also suggested the existence of oncogene on the short arm of chromosome 12.
Constructing tree models based on the CGH data to demonstrate the initiation and progression of NPC might help elucidate its multigene, multistep and multipathway development. It may provide valuable clues to explore the mechanism of tumorigenesis.
Zhonghua zhong liu za zhi [Chinese journal of oncology] 04/2004; 26(3):135-8.
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ABSTRACT: In order to elucidate the role of EBV-LMP1 in the nasopharyngeal carcinogenesis, the expression vector was constructed with subjecting the N-LMP1 gene to double regulation of two specific regulators: EDL-2 and PLUNC-p. The N-LMP1 related transgenic mice model has been constructed successfully by pronucleus microinjection. 58 founder mice were born, 4 of which were founded to be positive by PCR and Southern blot. Immunohistochemistry assay showed that N-LMP1 protein was expressed in the nasopharynx, tongue and forestomach of transgenic mice.
Sheng wu hua xue yu sheng wu wu li xue bao Acta biochimica et biophysica Sinica 01/2004; 35(12):1072-6.
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ABSTRACT: The GATA-1 of Xenopus (xGATA-1), which has two subtypes xGATA-1a and xGATA-1b, is a necessary factor for erythroid differentiation and maturation as similar as that of other GATA-1s. Although both xGATa-1a and xGATA-1b are able to stimulate erythropoiesis, only xGATA-1b is capable of inhibiting neurogenesis in Xenopus embryos. Compared between their structures, xGATA-1a and xGATA-1b are very similar in nucleotide and amino acids composition, but not identical. Therefore, it is responsible for studying the role of the diverse codons between the two genes, so the desired mutations: S(168), H(169) double deletion and point mutation of T(304)-->A, T(359)-->A, were introduced into xGATA-1b gene through site-directed mutagenesis. Then, mRNA from each mutant as well as wtxGATA-1b was co-injected with DN-BR mRNA or separately injected into Xenopus stage 2 embryos, and the role of mutants in erythropoiesis and neurogenesis was analyzed by using animal cap culture system. The results showed that the neural-inhibiting activity of xGATA-1b, but not hematopoiesis-inducing activity, was aborted because of deletion of Ser(168) and His(169) or point mutation of T(359)-->A. So it is demonstrated for the first time that Ser(168) and His(169) or Thr(359)in xGATA-1b may be one of the structural basis for explanting the different function between xGATA-1b and xGATA-1a.
Sheng wu hua xue yu sheng wu wu li xue bao Acta biochimica et biophysica Sinica 01/2004; 35(12):1105-10.
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ABSTRACT: The mechanism of how stromal cell play an important role in nasopharyngeal carcinogenesis is now a hotspot. This study was designed to elucidate the possible mechanism of stromal cell in the occurrence and progression of nasopharyngeal carcinoma (NPC) through the analysis of the characteristics of gene expression in pericancerous stromal cells of NPC by cDNA array.
The atlas human select tumor arrays were used to compare the expression profiles between NPC tissue and NPC cell lines.
Pericancerous stromal cells in NPC expressed at least 40 genes specifically.
The specific expression of these genes in pericancerous stromal cells provides energy materials for growth of NPC cells; furthermore, it can accelerate the degradation of extracellular matrix, thus promoting the metastasis of NPC cells.
Ai zheng = Aizheng = Chinese journal of cancer 03/2003; 22(3):235-8.
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ABSTRACT: Microdissection has become indispensable for the selective analysis of stroma-free tumor cell. However, To obtain sufficient RNA from microdissected cells is difficult. The study was designed to seek a specific way to separate nasopharyngeal carcinoma (NPC) cells from stromal cells and to amplify the RNA from microdissected NPC cells.
NPC cells were obtained using microdissection from frozen NPC tissue sections, then RNA was extracted from the microdissected NPC cells and reverse transcribed in vitro. The expression levels of beta-actin and GADPH in amplified RNA were detected using RT-PCR.
About 20,000-40,000 NPC cells were obtained, RNA was extracted from the cells, about 0.5-2.5 kb RNA fragments were obtained after RNA linear amplification and beta-actin and GADPH levels were integral.
Microdissection combined with RNA linear amplification can be used to successfully obtain pure NPC cells, the integrity of amplified RNA is good and can be used in further research.
Ai zheng = Aizheng = Chinese journal of cancer 09/2002; 21(9):1022-5.
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ABSTRACT: To compare gene expression gene profile of nasopharyngeal carcinoma (NPC) tissue with that of normal nasopharyngeal tissues by cDNA array and to discuss possible functions of DNA repair-related genes in NPC tissue.
After hybridization of atlas human cancer cDNA expression array 7742 - 1, atlas hybridization results were analyzed by Atlas Image 1.01 a software package. Using RT-PCR was used to confirm the results.
Of 63 differentially expressed genes in quadrangle C including DNA damage response, repair & recombination-related genes, 6 DNA repair-related genes were up-regulated, 12 were down-regulated.
DNA repair-related genes may be involved in patho-physiological process of nasopharyngeal carcinoma.
Zhonghua zhong liu za zhi [Chinese journal of oncology] 03/2002; 24(2):114-7.
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ABSTRACT: Objective: To compare gene expression profiles of nasopharyngeal carcinoma (NPC) tissue with that of control tissue by cDNA
Array and to discuss possible reasons of TP53 accumulation in NPC tissue. Methods: (1) hybridization of Atlas Human Cancer
cDNA Expression Array 7742-1; (2) analysis of Atlas Arrays using Atlasimage 1.01a; (3) verification of results of array by
RT-PCR; (4) verification of protein expression alterations by immunohistochemistry. Results: (1) Of 588 tumor-related genes,
134 genes were upregulated, 88 downregulated; (2) Of 32 TP53-regulated genes, 13 genes were shown differential expression,
11 upregulated, 2 downregulated; (3) ATM and JNK2 were upregulated; (4) mRNA expression of ubiquitin-conjugating enzyme E2
(M74524) and ubiquitin-conjugating enzyme E2 (L22005) has no evident changes; Conclusion: (1) TP53 dysfunction exists in NPC
tissues; (2) ATM and JNK might be the important causes of TP53 accumulation.
Chinese Journal of Cancer Research 02/2002; 14(1):28-32. · 0.18 Impact Factor
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ABSTRACT: To construct an animal model of nasopharygeal carcinoma with a nasopharynx-specific regulator, we cloned the gene YH1, which is specifically and highly expressed in human nasopharynx and trachea, through scanning high-density gene filtering. A BLAST screen against GenBank showed that this gene is a close homologue to the PLNUC gene, which is strictly expressed in mouse embryonic palate, nasal epithelium and lung and in the trachea of the adult mouse. The same result was obtained by using the polymerase chain reaction with reverse transcription. We cloned and sequenced the 5' flanking sequence of PLUNC with a GenomeWalker kit; this new sequence has been submitted to GenBank (No. 225964). Its promoter activity was confirmed by a luciferase report gene test. The core promoter was 200 base pairs upstream from the transcription starting site. We constructed a green fluorescent protein expression vector with the new promoter, and it showed a specific expression profile in a transgenic Xenopus model. We are now using this promoter to induce the expression of the EBV-BNLF1 gene, and we will transfer this vector to mice by microinjection of fertilized pronuclear eggs.
Nature Genetics. 03/2001;
