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Publications (11)10.4 Total impact

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    ABSTRACT: Previous studies indicate that heparanase (HPA), an endoglycosidase involved in tumor angiogenesis and metastasis, is up-regulated in a variety of malignancies. However, the expression of HPA in neuroblastoma (NB), one of the most common extra cranial solid tumors in children, remains unknown. This study was undertaken to explore the expression and clinical significance of HPA in NB. Immunohistochemical staining was applied to detect the expression of HPA in 42 cases of NB. The relationships among HPA expression, international neuroblastoma staging system (INSS) stages, histopathological classification, and postoperative survival of the NB patients were analyzed. The expression rate of HPA in NB was 61.9% (26/42), mainly in the cytoplasm of neuroblastoma cells. The expression rates of stage 1-2, stage 3-4 and stage 4S were 35.7%, 80.0% and 62.5%, respectively. The differences between stage 1-2 and stage 3-4 were significant (P<0.01). The expression of HPA was significantly higher in the NB cases that had one of the histopathological factors: age more than 1 year (P<0.01), poorer differentiation (P<0.01), and higher mitosis karyorrhexis index (P<0.01). The survival time of HPA-negative patients was significantly longer than that of HPA-positive patients (P<0.05). Although these results indicate that heparanase might be correlated with development and progression of NB, a larger series of patients with a longer follow-up are probably needed to strengthen its role in assessment of NB prognosis.
    World Journal of Pediatrics 08/2009; 5(3):206-10. · 1.08 Impact Factor
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    ABSTRACT: Reoperative orchidopexy is a technical challenge to pediatric surgeons. The laparoscopy-assisted procedure is described for securing the testis in the scrotum in patients with a past history of open orchidopexy and testes in an unsatisfactory position. Thirty-one patients with 35 abnormally positioned testes (4 bilateral) were evaluated. All patients had a past history of inguinal surgery, and ages ranged between 2.5 and 13 years (mean, 5.5 years). Previous surgical procedures included 32 orchiopexies and 3 testicular detorsion of undescended testis. If needed, inguinal dissection was performed to loose the adherence between the cord and inguinal canal. Laparoscopic orchidopexy was applied to allow the testis to remain in the scrotum without tension. Patients underwent follow-up every 3 months after the operation with physical and ultrasound examinations. Ten low inguinal testes were treated directly with open inguinal redo orchidopexy, whereas laparoscopy-assisted orchidopexy was possible in 23 (92%) of the remaining 25 reoperations. In 2 (8%) of these cases, severe scarring was present between the cord and the inguinal canal impeding the laparoscopy-assisted orchidopexy. For laparoscopy-assisted procedure, the operation time was 42 to 67 minutes (mean = 52 min). After the laparoscopy-assisted reoperations, 23 (92%) testes remain within the scrotum after a mean follow-up of 22 months (range, 6-32 months). When feasible, laparoscopy-assisted orchiopexy is a simple and effective technique for securing testicles in reoperative orchiopexy procedures.
    Journal of Pediatric Surgery 05/2009; 44(4):806-10. · 1.38 Impact Factor
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    ABSTRACT: To clone the mouse testis specific gene TSEG-2 via a bioinformatic approach. The expressed sequence tags (EST) in the normal mouse testis were obtained from the online EST database ZooDDD. Their highly homologous EST sequences were retrieved through the dbEST database to construct contigs and spliced with the biomedical software Biolign. The corresponding exons and introns within the genome sequences were predicted with the software GeneScan. Primers were designed according to the open reading frame. RT-PCR was applied in cloning the cDNA of the novel gene from the mouse testis tissue and analyzing its expression patterns in the undescended testis and various organ tissues as well as in different developmental stages of the mouse testis. The sequencing results of TSEG-2 underwent bioinformatic analyses. The novel mouse testis gene TSEG-2 was successfully cloned, with full-length sequence of 451 bp. The open reading frame was 267 bp, coding a protein of 88 amino acid residues, and demonstrated to be correct by RT-PCR. The expression of TSEG-2 was high in the mouse testis, regular in the testis cDNA samples of different postnatal days, and down-regulated in the cryptorchidism model. No obvious homology with other mouse cDNA was found for TSEG-2. The GenBank accession number EU079025 was achieved. Function prediction showed that mouse TSEG-2 was probably a soluble non-secretary protein located at chromosome 15qE3, or a nucleoprotein with 2 phosphorylation sites of protein kinase C (PKC) and 1 of casein kinase II (CK2). A novel mouse testis specific gene TSEG-2 was successfully cloned, which could be down-regulated by cryptorchidism-inducible 17-beta estradiol. This has prepared the ground for further researches on the biological function and expression regulation of TSEG-2.
    Zhonghua nan ke xue = National journal of andrology 03/2009; 15(2):99-105.
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    ABSTRACT: Previous studies have indicated that resistin-like molecule beta (RELM beta), an intestinal goblet cell-specific protein, is markedly increased in the intestinal tumors of min mice and over-expressed in a human colon cancer cell line. We hypothesized that RELM beta might be enhanced in human colon cancer. The aim of this study was to examine the clinical importance of RELM beta expression in colon cancer patients and to correlate its expression with various clinicopathological parameters, upstream regulatory molecule expression, tumor proliferative capacity, and patients' survival. Of the 80 colon cancer patients studied, 65 (81.25%) tested positive for RELM beta, mainly in the cytoplasm of colon mucosa. Contrasting sharply with the strongly RELM beta-positive tumors, normal colon mucous membrane was negative or weakly positive. RELM beta positivity in colon cancer was correlated with histological grade of differentiation and lymph node metastasis, but not with age, gender, tumor location and size, tumor infiltration, Dukes' stage, liver metastasis, and venous invasion. RELM beta expression was significantly correlated with the expression of transcription factor CDX-2 (P < 0.01) but not with that of proliferative index Ki-67 (P > 0.05). The mean postoperative survival time (2.76 years) of RELM beta-positive patients was significantly longer than that (1.26 years) of RELM beta-negative patients (P = 0.032). These findings support evidence of the enhanced RELM beta expression in colon cancer patients and suggest that further investigation is warranted to explore the role of RELM beta in colon cancer.
    Digestive Diseases and Sciences 08/2008; 54(2):274-81. · 2.26 Impact Factor
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    ABSTRACT: This study is to explore the inhibitory effect of methyl jasmonate on cell proliferation and expression of XIAP and survivin of human neuroblastoma cell line BE(2)-C. After cultivation of 1 - 2 mmol x L(-1) jasmonates with BE (2) -C cells for 6 - 24 h, the growth inhibiting rates of BE (2) -C cells were studied by MTT colorimetry. Cell proliferation was detected by colony formation assay. Cell cycle phases were assayed by propidium iodide staining flow cytometery. Cell apoptosis was inspected by acridine orange-ethidium bromide fluorescent staining, Hoechst 33258 fluorescent staining, and Annexin V-FITC and propidium iodide staining flow cytometry. Expressions of cyclin D1, XIAP and survivin were determined by RT-PCR and real-time RT-PCR. Methyl jasmonate inhibited the growth of BE(2)-C cells in a dose- and time-dependent manner. After addition of 1, 1.5 and 2 mmol x L(-1) of methyl jasmonate for 24 h, the inhibiting rates of cell growth reached 20.6% - 85.5% (P < 0.01), and the IC50 was 1.35 mmol x L(-1). The cell cycles were arrested at S phase. A part of cells presented the characteristic morphological changes of apoptosis. The early apoptotic rates were 13.51%, 17.32%, 24.59% (P < 0.01) and the cell death rates were 29.36% , 54.73% , 75.52% (P < 0.01), respectively. The expression of XIAP and survivin mRNA were downregulated by 18.5% - 68.9% , 22.4% - 48.7% (P < 0.05), respectively, without change in that of cyclin D1. The results indicated that methyl jasmonate could significantly inhibit the growth of BE(2) -C cells through inducing cell cycle arrest and apoptosis, downregulating the expression of XIAP and survivin might be one of its molecular mechanisms of action.
    Yao xue xue bao = Acta pharmaceutica Sinica 07/2008; 43(6):584-90.
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    ABSTRACT: Recent evidence has indicated that members of natural jasmonates, a family of plant stress hormones, exhibit anticancer activity. The current study was undertaken to investigate the effects of jasmonates on the in vitro growth of human neuroblastomas, one of the most common solid tumors in children. Cellular proliferation was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide colorimetry and colony formation assay. Apoptosis was detected by Hoechst 33258 staining and flow cytometry. Western blotting was applied to assay gene expression. The administration of natural jasmonates, methyl jasmonate, cis-jasmone, and jasmonic acid to cultured neuroblastoma cell line SH-SY5Y, resulted in a decrease of cell proliferation in a doseand time-dependent manner. However, the in vitro growth of cultured human embryonic kidney (HEK) cell line HEK 293 was not affected by jasmonates. The cell cycles of jasmonate-treated SH-SY5Y cells were arrested at the G2/M phase. The incubation of SH-SY5Y cells with jasmonates resulted in characteristic changes of apoptosis. The anticancer activities of natural jasmonates on SH-SY5Y cells are as follows: methyl jasmonate>cis-jasmone>jasmonic acid. In addition, the expressions of proliferating cell nuclear antigen and N-myc were downregulated by methyl jasmonate. Moreover, methyl jasmonate decreased the expression of the Xlinked inhibitor of apoptosis protein and survivin, critical members of inhibitors of the apoptosis protein family, in SH-SY5Y cells. Jasmonates suppress the growth of human neuroblastoma cell line SH-SY5Y via inhibiting cell proliferation and inducing apoptosis, which lays the groundwork for further investigation into the anticancer activities and its mechanisms of natural jasmonates on human neuroblastomas.
    Acta Pharmacologica Sinica 07/2008; 29(7):861-9. · 2.35 Impact Factor
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    ABSTRACT: Recent evidence indicates that methyl jasmonate, a plant stress hormone, exhibits anticancer activity on human cancer cells. Whether methyl jasmonate could inhibit the growth of human neuroblastoma cells still, however, remains largely unknown. In this study, administration of methyl jasmonate to cultured neuroblastoma cell lines, SK-N-SH and BE(2)-C, resulted in a decrease of cell viability in a dose-dependent and time-dependent manner as demonstrated by MTT colorimetry and colony formation assay. The results from RT-PCR indicated that the expression of proliferating cell nuclear antigen, but not of cyclin D1, was downregulated by methyl jasmonate. Accordingly, the cell cycle of methyl jasmonate-treated neuroblastoma cells was arrested at the G0/G1 phase. Moreover, incubation of SK-N-SH and BE(2)-C cells with methyl jasmonate resulted in characteristic changes of apoptosis, as demonstrated by acridine orange-ethidium bromide (AO/EB) staining, Hoechst 33258 staining and flow cytometry. Moreover, methyl jasmonate decreased the expression of the X-linked inhibitor of apoptosis protein and survivin, critical members of the inhibitors of apoptosis protein family, in neuroblastoma cells. These findings indicate that methyl jasmonate suppresses the growth of cultured human neuroblastoma cells associated with downregulation of proliferating cell nuclear antigen, and induces apoptosis accompanied by downregulation of the X-linked inhibitor of apoptosis protein and survivin, which lays the groundwork for further investigation into the mechanisms of methyl jasmonate-mediated anticancer activities.
    Anti-Cancer Drugs 07/2008; 19(6):573-81. · 2.23 Impact Factor
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    ABSTRACT: The expressed sequence tags (ESTs) of normal mouse testis were obtained from online EST database ZooDDD. Their highly homologous EST sequences were found through the dbEST database to construct contigs, and spliced by the biomedical software Biolign. The corresponding exons and introns within genome sequences were predicted by software GeneScan. According to the open reading frame, the primers were designed. RT-PCR was applied in the cloning of novel gene from mouse testis and analyzing its expression pattern in various mouse tissues. The bioinformatics analysis on the sequencing results of TSEG-1 was conducted. Results indicated that a novel gene TSEG-1 was cloned from 1 668-2 011 kb of mouse X chromosome, with full-length sequence of 510 bp. The open reading frame (ORF) is 336 bp in length and en-codes a deduced amino acid sequence of 111 residues. The molecular weight of TSEG-1 protein is 12.84258 kDa, and its pI is 11.4000. RT-PCR demonstrated the correctness of its ORF. TSEG-1 was distinctively expressed in testis, but not in other tissues of mouse. No obvious homology with other mouse cDNA was found for TSEG-1. The GenBank accession number EU079024 was achieved. It was predicted that TSEG-1 is a kind of transmembrane protein, and the transmembrane domain is from 41 amino acid residue to 61 amino acid residue. Blastn analysis revealed its high homology to human testis-specific gene H2AX. Computational prediction of the 5'-untranslated region of TSEG-1 gene revealed a 680 bp-length promoter region. There are four antigen binding sites and two phosphorylation sites of specific protein kinase in TSEG-1 protein, with subcellular localization in mitochondria. The cloning of mouse testis specific gene TSEG-1 laid a foundation for subsequent research of its biological function and expression regulation.
    Hereditas (Beijing) 04/2008; 30(3):352-8.
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    ABSTRACT: Expressed sequence tags (EST) are short, randomly selected single-pass nucleotide sequence reads derived from cDNA libraries and represent a small part of a gene. Along with the development of bioinformatics and genetic localization, EST has already become a powerful tool for mapping, cloning and expression profiling of genes. Recently, because of the fast distension of EST databases, application of EST in gene mapping and cloning leads to revolutionary change in the strategies for cloning of novel genes. Despite of some insufficiencies, it has been proved that EST could promote the discovery and research of novel genes. In this article, an introduction about EST, especially EST-based strategies for cloning of novel genes will be given in details.
    Hereditas (Beijing) 04/2008; 30(3):257-62.
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    ABSTRACT: Recent evidences indicate that CD133, a kind of transmembrane protein, can be used as a marker to isolate stem cells from tumors originating from neural crest. This study was undertaken to explore the expression and clinical significance of stem cell marker CD133 in neuroblastoma (NB). Immunohistochemical staining was used to detect the expression of CD133 in 32 patients with NB and 8 patients with ganglioneuroblastoma (GNB). The relationships were analyzed among CD133 expression, international neuroblastoma staging system (INSS) stages, pathological classification, and postoperative survival time of NB patients. The expression rates of CD133 in NB and GNB were 46.9% (15/32) and 37.5% (3/8) respectively, mainly in cytoplasm of neuroblastoma cells. The expression rates of stage 1-2, stage 3-4 and stage 4S were 30.7%, 57.9% and 37.5%, respectively. The differences in various stages were significant (P<0.05). The positive rate of CD133 in patients with unfavorable histology (52.4%) was significantly higher than that in patients with favorable histology (36.8%) (P=0.007). The survival time of CD133 negative patients was significantly longer than that of CD133 positive patients (P=0.026). CD133 which might be correlated with the development and progression of NB can serve as one of the important indicators for prognosis of NB.
    World Journal of Pediatrics 02/2008; 4(1):58-62. · 1.08 Impact Factor
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    ABSTRACT: Background: Recent evidences indicated that tumor cells could induce apoptosis of T cells by combining Fas on active T cells' surface with self-expressed FasL to escape immune surveillance. This study was undertaken to detect the expression of the Fas/FasL system in neuroblastoma (NB) tissues and its clinical significance in clinical practice. Methods: Immunohistochemical staining was performed to detect the expression of Fas and FasL in 40 cases of NB. The relations among Fas and FasL expression, clinical stages, pathological types, and postoperative survival time of patients were analyzed. Results: The positive expression rates of Fas in I-II, III-IV and IV-S stages were 64.3%, 22.2% and 50.0% respectively (P