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Yi-xin Zeng

Publications and source records attributed to Yi-xin Zeng.

12 recordsLinked to original sources
PubMed2006

[Cytokine-induced killer cell fusion to lower recurrence of hepatocellular carcinoma after transcatheter arterial chemoembolization sequentially combined with radiofrequency ablation: a randomized trial].

OBJECTIVE: To ed evaluate the clinical effects of autologous cytokine-induced killer cell (CIK) fusion to lower recurrence of primary hepatocellular carcinoma (HCC) and the anti-hepatitis B virus (HBV) effect after transcatheter arterial chemoembolization (TACE) sequentially combined with radiofrequency ablation (RFA). METHODS: Sixty-four HCC patients underwent TACE sequentially combined with RFA without residual tumor or extrahepatic metastasis were randomly divided into 2 groups: study group (n = 33), receiving autologous CIK fusion of the dose of (1.1 - 1.5) x 10(10) via the peripheral vein or hepatic artery, firstly once every 3 - 4 weeks for 4 times, and then once every 4 weeks for 4 times; and control group (n = 31). All patients were followed up for 1 year. RESULTS: In the study group, 29 patients (29/33) were recurrence-free during the 1 year follow-up, 3 had recurrence in the liver 5, 6, and 7 months later respectively, and 1 patient had lymphoadenopathy in the hepatic portal 9 months later. In the control group, 23 patients (68.01%) were recurrence-free, 7 had recurrence in the liver within 1 year, and 1 had lung metastasis 11 months later. In the study group, the number of the patients with the HBV DNA content < 1 x 10(3) before treatment was 19, and increased to 29 after the treatment; 2 of the 19 patients who were HBsAg positive before the treatment became HBsAg negative after the treatment, and number of the patients with the HBV DNA content of 10(3) - 10(4) was 3 before the treatment, and became 13 after the treatment among which 1 patient had his HBV DNA content dropping from 1.6 x 10(7) to 1.6 x 10(4). In the control group, only 1 patient showed his HBV DNA content dropping from 1.1 x 10(5) to below 10(3). CONCLUSION: Capable of reducing recurrence, prolonging the recurrence-free span, and attacking HBV, autologous CIK fusion after TACE sequentially combined with RFA is an effective novel therapeutic strategy for HCC.

Adult↗
PubMed2006

[Study on genetic polymorphisms of CYP2F1 gene in Guangdong population of China].

OBJECTIVE: To investigate the genetic polymorphism of CYP2F1 gene, a member of CYP450 gene family in the healthy population and the patients with nasopharyngeal carcinoma (NPC) of Guangdong province, and furthermore analyze the relationship between CYP2F1 genetic polymorphism and the risk of developing NPC. METHODS: By direct gene sequencing, all of 10 exons of CYP2F1 gene were detected in 40 peripheral blood specimens of patients with primary NPC. For the genetic polymorphism with high allelic frequency, mismatch PCR-RFLP technique was developed to identify the different frequency between 368 NPC cases and 344 cancer-free controls. RESULTS: There were totally 35 SNPs identified in all of 10 exons and exon-intron junctions of CYP2F1 gene from 40 NPC patients, which included 10 missense mutations and 1 frame shift mutation. The most important mutation was C insertion located in 15-16 bp, which caused the frame shift. The allelic frequency of C insertion was 25%. However, there was no significant difference found between 368 NPC cases and 344 controls in allelic frequency of 15-16 bp C insertion mutation (P>0.05). CONCLUSION: A lot of genetic polymorphism of CYP2F1 gene is found in Guangdong population of China. However, no single genetic polymorphism associated with the individual susceptibility to NPC can be identified. The cooperated operations with multiple genetic polymorphisms of one or more genes may be critical factors contributing to the development and progression of NPC.

Asian People↗
PubMed2005

[NP9 gene inhibits tumorigenicity of nasopharyngeal carcinoma].

OBJECTIVE: To study the effect of NP9 on the growth of transplanted nasopharyngeal carcinoma (NPC) in nude mice and explore the mechanisms involved. METHODS: Recombinant pRc/CMV2-NP9 plasmid was constructed and transfected into the NPC cell lines by lipofectamine 2000. Cell clones stably expressing NP9 were obtained by detecting the mRNA expression of NP9 in G418-resistant clones with RT-PCR. The tumorigenicity and size of transplanted tumors were assessed after inoculation of NPC cells and their transgene clones into Balb/C mice. The expression of PCNA and cyclin D1 in transplanted tumors was detected by immunohistochemistry. RESULTS: The expression of NP9 was detected in some of NP9 gene-transfected G418-resistant clones of CNE1 and SUNE1. In vivo experiments showed that the tumorigenicity of CNE19 clone was decreased significantly compared to that of CNE1 and its vector control, and the transplanted tumors grew more slowly from SUNE1/NP9 than from SUNE1 and SUNE1/vector. Compared with the vector control, the expression of cyclin D1 and PCNA in CNE1/NP9 transplants was decreased. CONCLUSION: NP9 inhibits tumorigenicity and growth of NPC transplanted tumor by down-regulating the expression of cyclin D1 and PCNA.

Animals↗
PubMed2004

p21WAF1/CIP1 gene DNA sequencing and its expression in human osteosarcoma.

BACKGROUND: Mutation and expression change of p21WAF1/CIP1 may play a role in the growth of osteosarcoma. This study was to investigate the expression of the p21WAF1/CIP1 gene in human osteosarcoma, p21WAF1/CIP1 gene DNA sequence change and their relationships with the phenotype and clinical prognosis. METHODS: p21WAF1/CIP1 gene in 10 normal people and the tumours of 45 osteosarcoma patients were examined using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) with silver staining. The PCR product with an abnormal strand was sequenced directly. The p21WAF1/CIP1 gene mRNA and P21 protein of 45 cases of osteosarcoma were investigated by using in situ hybridization and immunohistochemistry, respectively. RESULTS: The occurrence of P21 protein in osteosarcoma was 17.78% (8/45), and p21WAF1/CIP1 mRNA expression in osteosarcoma was 42.22% (19/45). The p21WAF1/CIP1 gene DNA sequencing of amplified production showed that in p21WAF1/CIP1 gene exon 3 of 36 cases of human osteosarcoma, there were 17 cases (47.22%) with C-->T at position 609; 10 normal blood samples' DNA sequence analysis yielded 8 cases (80.00%) with C-->T at the same position. CONCLUSIONS: Along with the increase of malignancy, the expression of p21WAF1/CIP1mRNA and P21 protein in osteosarcoma tends to decrease. It is uncommon for the p21WAF1/CIP1 gene mutation to occur in human osteosarcoma. As a result, the possible existence of tumour subtypes of p21WAF1/CIP1 gene mutation should be investigated. Our research leads to the location of p21WAF1/CIP1 gene polymorphism of Chinese osteosarcoma patients, which can provide a basis for further research.

Cyclin-Dependent Kinase Inhibitor p21↗
PubMed2004

Inhibition of tumor growth in xenografted nude mice with adenovirus-mediated endostatin gene comparison with recombinant endostatin protein.

BACKGROUND: Inhibition of tumor growth by endostatin has been shown to be an effective strategy in cancer therapy in mice. However, its widespread application has been hampered by difficulties in a large-scale production of the recombinant endostatin protein, rapid loss bioactivity of the protein, and the cumbersome daily administration. These limitations could be resolved by in vivo delivery and expression of the endostatin gene. In this study, we observed the effect and advantage of endostatin gene therapy mediated by a recombinant adenoviral vector (Ad/hEndo) on the growth of hepatocellular carcinoma BEL-7402 xenografted tumors, comparison with recombinant endostatin protein. METHODS: Hepatocellular carcinoma BEL-7402 cells were inoculated subcutaneously in the flank of Balb/c nude mice. Nine days after tumor cell inoculation, animals were given a cycle of four courses of intra-tumoral injections of Ad/hEndo of 5 x 10(8) pfu (low-dose group) and 1 x 10(9) pfu (high-dose group) at intervals of six days, respectively. Recombinant human endostatin protein (rhEndo) was administrated daily subcutaneously at a dose of 10 mg.kg(-1).d(-1) at a site nearby the tumor for ten days. The expression of endostatin mRNA in tumor tissue was analyzed by reverse transcription-polymerase chain reaction (RT-PCR) after Ad/hEndo injection. Dynamic changes of concentration of endostatin protein in tumor tissue were quantitated by enzyme-linked immunosorbent assay (ELISA). RESULTS: After 4 courses of treatment, the tumor growth rates of high-dose treated group with 1 x 10(9) pfu of Ad/hEndo were inhibited by 42.26% compared with the Ad/LacZ control group (P = 0.001) and by 46.26% compared with the NIH buffer control group (P = 0.003), respectively. However, in this study, Ad/hEndo at low dose of 5 x 10(8) pfu failed to demonstrate significant inhibition of tumor growth, compared with control groups. After daily administration of recombinant human endostatin protein (rhEndo) for 9 days, the ratio of T/C (rhEndo group versus PBS group) was less than 47%. However, two days after rhEndo treatment ceased, the ratio of T/C was more than 50%. The peak of expression of endostatin mRNA in tumor tissue was at 2 or 3 days after administration intratumorally with Ad/hEndo of 1 x 10(9) pfu and gradually dropped undetectable by day 7. Dynamic analysis of endostatin concentration in tumor tissue showed that the highest level of mRNA is up at the third day after injection, and dropped to basal level three weeks later. CONCLUSIONS: Endostatin gene therapy mediated by a recombinant adenoviral vector had significantly inhibited the growth of hepatocellular carcinoma BEL-7402 xenografted tumors at a high dose of 1 x 10(9) pfu compared with other groups. The analysis of dynamic expression of endostatin in vivo indicated that Ad/hEndo had acquired a high-level, relatively long-term expression in vivo and bioactivity capability.

Adenoviridae↗
PubMed2003

[Inhibitive effects of recombinant adenovirus-mediated human endostatin on the growth of human hepatocellular carcinoma xenograft in nude mice].

OBJECTIVE: To investigate the inhibitive effect on the growth of hepatocellular carcinoma (HCC) xenografted in nude mice by adenovirus-mediated human endostatin gene. METHODS: The expression efficiency of endostatin was examined after ECV-304 cells infected with Ad/hEndo by western blot. The hepatoma BEL-7402 cells were injected into Balb/c nude mice to detect the inhibition of Ad/hEndo on the growth of HCC xenografted in nude mice. The expression of endostatin mRNA in tumor tissue was analyzed with RT-PCR, and its distribution in vivo was also analyzed. RESULTS: High level expression of endostatin achieved in infected ECV-304 cells by western blot. Ad/hEndo significantly inhibited the growth of xenografted BEL-7402 tumors (F=4.061, P<0.05). The intratumoral microvessel density (MVD) decreased significantly in the treated mice (6.88+/-1.08 vs 13.60+/-1.71, t=9.216, P<0.01). The expression of endostatin mRNA in tumor tissue was detected by RT-PCR in 3 days after administration intratumorally with Ad/hEndo and almost disappeared in 7 days. Endostatin mRNA was mainly located in tumor tissue with a higher concentration than that in heart, lung, spleen and liver after Ad/hEndo administration. CONCLUSION: Adenovirus-mediated human endostatin gene can be expressed efficiently in vitro and in vivo, and significantly inhibit the growth of BEL-7402 xenografted tumors in nude mice.

Adenoviridae↗
PubMed2002

[A method to detect gene transfection efficacy by flow cytometry].

BACKGROUND & OBJECTIVE: Analysis of gene transfer and expression is conventionally inferred from the percentage of positive cells expressing reporter gene in total cells, referred as transfection rate, by investigators counting under a microscope or fluoroscope, which was called as manual counting. But in many cases, it is not accurate and easily influenced by the subjectivity of observer. This study was designed to seek a convenient method to assess objectively and accurately the efficacy of gene transfer and expression. METHODS: Hepatocellular carcinoma(HCC) HepG2 cells were infected with a recombinant adenovirus expressing green fluorescent protein(AdCMV/GFP) at a series of multiplicities of infection(MOIs). 24 h later, the transfection rates were assessed by manual counting under fluorescent microscope. Meanwhile, besides transfection rates, fluorescent indices(FIs) which indicated the efficiency of gene transfer and expression were analyzed by flow cytometry (FCM). Transfection efficiencies of AdCMV/GFP to HCC Hep3B, Bel7402, SMMC7721 cells and nasopharyngeal carcinoma CNE-2 cells were also tested by FCM. RESULTS: Although transfection rates by FCM were slightly higher than that by manual counting, both were logarithmic correlative with vector doses. The stirring was that FIs by FCM showed compellent linear correlation with vector doses (r = 0.9984, P < 0.001). The efficiency of gene transfer in other cells by FCM were similar to that in HepG2. CONCLUSION: The efficiency of gene transfer and expression in mammalian cells can be easily analyzed by flow cytometry, which is more sensitive, objective, and accurate than manual counting, especially in assessing the efficiency of multiple gene transfer (multi-copies per cell) and expression.

Adenoviridae↗
PubMed2002

[Gene expression profiling in nasopharyngeal carcinoma determined by high density cDNA microarray].

BACKGROUND & OBJECTIVE: Multiple steps and gene expression changes were involved in the development and progression of nasopharyngeal carcinoma (NPC), but the molecular mechanism is not understanding clearly. This study was designed to investigate the profiling of differently expressed genes in nasopharyngeal carcinoma compared with noncancerous nasopharynx tissues to explore the feature of gene expression in NPC and identify new candidate genes related to the development and progression of NPC. METHODS: Differently expressed genes of NPC in 21 cases, which were divided into three pools, were investigated by using high density cDNA microarray representing 18,000 cDNA clones. The alterations in gene expression levels were confirmed by reverse-transcription PCR in 2 randomly selected genes. RESULTS: A total of 317 genes were identified to be differently expressed in NPC of three pools as compared with noncancerous controls. Among the 317 genes, 23 genes were found to be consistent in at least two NPC sample pools, including 16 up-regulated genes and 7 down-regulated genes. Six genes were found to be consistent in all the three NPC sample pools. The 6 genes include 2 up-regulated unknown genes, 3 up-regulated unknown genes and 1 down-regulated unknown gene. CONCLUSION: The present study represents a global view of gene expression of NPC and provides important clues for further study of NPC related genes.

Gene Expression↗
PubMed2002

[Molecular genetic progression on nasopharyngeal carcinoma].

The aim of this paper was to discuss the molecular genetic events in the development and progression of nasopharyngeal carcinoma (NPC), and the correlation between genetic alterations and clinicopathological changes of NPC. Analyzed by LOH (loss of heterozygosity) and CGH (comparative genomic hybridization) in primary NPC, high frequent allelic losses were observed on chromosomes 1p, 3p, 9p, 9q, 11q, 13q, 14q, 16q, and 19q, and the minimum deletion regions were also localized; there are closely association between LOH on certain deletion regions in NPC and the clinicopathological parameters. In the group of NPC with higher LOH value (FAL), together with higher antibody titers of EBV IgA/VCA and IgA/EA, most of the NPC showed more invasive of primary T stage (T3 + T4), TNM (III + IV stage) and far lymph node metastasis. High frequent chromosomal gain regions were observed on chromosomes 1q, 2q, 3q, 6p, 6q, 7q11.2, 8q, 11q13, 12, 15q, 17q, and 20q, indicating that there may exist oncogenes which are activated on the gain regions in NPC. CGH analysis showed that gains on chromosome 1q, 8q, 18q, and loss on 9p were closely related to advanced stage of NPC. LOH study also showed high frequent LOH on 3p in normal nasopharyngeal epithelium (74%) and dysplasia lesions (75%) from the Southern Chinese, suggesting that LOH at 3p may be an earlier genetic event of NPC tumorigenesis. Linkage analysis indicate that the HLA gene and cytochrome p4502E gene may be susceptibility genes of NPC. New potential susceptibility gene locus has also been localized by this study. cDNA microarray demonstrated differential expression of cell cycle proteins, anti-apoptotic factors, oncogenes/tumor suppressors, growth-enhancing factors of EGR1, tumor-derived growth factor 1, platelet-derived growth factor A chain; differential expression were also observed in different clinical stage NPC. Genetic instabilities (losses and gains) are common molecular events in NPC, and play very important role in the development and progression of NPC. Through LOH, CGH, linkage, and cDNA microarray study, we can find specific biomarkers of NPC, and will support us biomarkers which can be used for earlier diagnosis and prognosis of NPC. More importantly, these biomarkers may be useful in the development of a NPC molecular staging system, which could augment current clinicopathological classification and staging systems.

Chromosome Aberrations↗
PubMed2002

[Mutation analysis of KLF6 gene in human nasopharyngeal carcinomas].

BACKGROUND & OBJECTIVE: Nasopharyngeal carcinoma (NPC) is one of the most common cancers in South China and Southeast Asia. The etiological factor is believed to be the interaction between genetic susceptibility, EBV infection and environmental factors, involved in the multi-step process of carcinogenesis and development of NPC. However, the molecular pathology of NPC is unclear yet. Kruppel-like factor 6(KLF6) is a ubiquitously expressed nuclear transcription factor, which is deleted and/or mutated with high frequency in a subset of prostate cancer. This study was designed to investigate KLF6 mutation in NPC tumors and NPC cell lines. METHODS: Genomic DNAs from 19 NPC tumor biospies and 3 NPC cell lines were used in mutation detection of KLF6 coding region and splice sites by PCR-sequencing. 100 chromosomes from 50 random healthy individuals were used as control. RESULTS: In 3 of 19 NPC tissues, 3 different mutations (Glu75Val, Ser136Arg, Arg243 Lys) in KLF6 gene were found by PCR-sequencing. None of the 3 mutations were detected in the 50 random healthy individuals. CONCLUSION: KLF6 gene may be involved in carcinogenesis of sporadic NPC.

Base Sequence↗