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ABSTRACT: Identification of high-risk prognostic markers for stage II colorectal cancer (CRC) is currently a big challenge. CD133 is one of the most commonly used CRC stem cell markers. However, its specificity is controversial. Recent studies have demonstrated that the AC133 epitope of CD133, not the CD133 protein, is responsible for cancer stem cell identification. The aim of this study was to investigate the clinical significance of AC133 expression in stage II CRC. Two antibodies against CD133, including AC133 and Ab19898, were compared for their expression characteristics. AC133 was chosen for further immunohistochemical assessment on 176 stage II CRC primary tumors with at least 12 examined lymph nodes. The cutoff value for positive rate of AC133 expression was determined by ROC curve analysis. AC133 was analyzed for correlations with clinicopathological and prognostic parameters. The results indicated that AC133 was negative in adjacent noncancerous colorectal mucosa while positive in 116 cases (65.9 %) of primary tumors. AC133 expression was significantly correlated with preoperative serum carcinoembryonic antigen level (p = 0.006) and tumor differentiation grade (p = 0.019). Furthermore, high AC133 expression was identified as a significant predictor for poor disease-free survival and overall survival at both univariate (p = 0.009, 0.013, respectively) and multivariate levels (p = 0.022, 0.026, respectively). Our data suggest that AC133 is an independent adverse prognostic factor and a potential marker for survival classification in stage II CRC patients.
Medical Oncology 03/2013; 30(1):356. · 2.14 Impact Factor
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ABSTRACT: Clock genes drive about 5-15% of genome-wide mRNA expression, and disruption of the circadian clock may deregulate the cell's normal biological functions. Cryptochrome 1 is a key regulator of the circadian feedback loop and plays an important role in organisms. The present study was conducted to investigate the expression of Cry1 and its prognostic significance in colorectal cancer (CRC). In addition, the function of Cry1 in human CRC was investigated in cell culture models.
Real-time quantitative PCR, Western blot analysis and immunohistochemistry were used to explore Cry1 expression in CRC cell lines and primary CRC clinical specimens. MTT and colony formation assays were used to determine effects on cellular proliferation ability. The animal model was used to explore the Cry1 impact on the tumor cellular proliferation ability in vivo. Transwell assays were performed to detect the migration ability of the cell lines. Statistical analyzes were applied to evaluate the diagnostic value and the associations of Cry1 expression with clinical parameters.
Cry1 expression was up regulated in the majority of the CRC cell lines and 168 primary CRC clinical specimens at the protein level. Clinical pathological analysis showed that Cry1 expression was significantly correlated with lymph node metastasis (p = 0.004) and the TNM stage (p = 0.003). High Cry1 expression was associated with poor overall survival in CRC patients (p = 0.010). Experimentally, we found that up-regulation of Cry1 promoted the proliferation and migration of HCT116 cells, while down-regulation of Cry1 inhibited the colony formation and migration of SW480 cells.
These results suggest that Cry1 likely plays important roles in CRC development and progression andCry1 may be a prognostic biomarker and a promising therapeutic target for CRC.
PLoS ONE 01/2013; 8(4):e61679. · 4.09 Impact Factor
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ABSTRACT: The purpose of this research was to develop formulation of docetaxel-loaded biodegradable TPGS-b-(PCL-ran-PGA) nanoparticles for breast cancer chemotherapy. A novel diblock copolymer, d-α-tocopheryl polyethylene glycol 1000 succinate-b-poly(ε-caprolactone-ran-glycolide) [TPGS-b-(PCL-ran-PGA)], was synthesized from ε-caprolactone, glycolide and d-α-tocopheryl polyethylene glycol 1000 succinate by ring-opening polymerization using stannous octoate as catalyst. The obtained copolymers were characterized by (1)H NMR, GPC and TGA. The docetaxel-loaded TPGS-b-(PCL-ran-PGA) nanoparticles were prepared and characterized. The data showed that the fluorescence TPGS-b-(PCL-ran-PGA) nanoparticles could be internalized by MCF-7 cells. The TPGS-b-(PCL-ran-PGA) nanoparticles achieved significantly higher level of cytotoxicity than commercial Taxotere®. MCF-7 xenograft tumor model on SCID mice showed that docetaxel formulated in the TPGS-b-(PCL-ran-PGA) nanoparticles could effectively inhibit the growth of tumor over a longer period of time than Taxotere® at the same dose. In conclusion, the TPGS-b-(PCL-ran-PGA) copolymer could be acted as a novel and potential biologically active polymeric material for nanoformulation in breast cancer chemotherapy.
Integrative Biology 09/2011; 3(10):993-1002. · 4.51 Impact Factor
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ABSTRACT: Overexpressed DNA methyltransferase 1 (DNMT1) strongly contributes to tumor suppressor gene silencing in colorectal cancer (CRC). However, the underlying mechanism of DNMT1 overexpression is still unclear. MicroRNAs (miRNA) have been implicated as gene regulators controlling diverse biological processes, including carcinogenesis. In this study, we investigated whether some miRNA is involved in the regulation of DNMT1 and thus play a functional role in CRC. Our results showed that miR-342 was downregulated in CRC tissues and cell lines. Restoration of miR-342 resulted in a dramatic reduction of the expression of DNMT1 at both messenger RNA and protein levels by directly targeting its 3' untranslated region. This in turn reactivated ADAM23, Hint1, RASSF1A and RECK genes via promoter demethylation. Furthermore, the enhanced expression of miR-342 could significantly inhibit SW480 cell proliferation in vitro (P = 0.006). Further investigation demonstrated G(0)/G(1) cell cycle arrest in SW480 cells, which was associated with an upregulation of p21 and downregulation of cyclinE and CDK2. Overexpression of miR-342 also inhibited SW480 cell invasion. The in vivo antitumor effect was evaluated in SW480 cells with lentivirus-mediated expression of miR-342. Results showed that overexpression of miR-342 significantly inhibited tumor growth and lung metastasis in nude mice (P = 0.034). Our findings describe a new mechanism for the regulation of DNMT1 and aberrant DNA hypermethylation in CRC. This is also the first report to demonstrate that miR-342 may act as a tumor suppressor gene in CRC development. The newly identified miR-342/DNMT1 link provides a new, potential therapeutic target for the treatment of CRC.
Carcinogenesis 05/2011; 32(7):1033-42. · 5.70 Impact Factor
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ABSTRACT: The formulation of docetaxel available for clinical use (Taxotere) contains a high concentration of polysorbate 80 (Tween 80). After incorporation of Tween 80 into poly-ɛ-caprolactone (PCL)-Tween 80 copolymer, the relative amount of Tween 80 should be decreased and the advantages of PCL and Tween 80 should be combined.
A novel PCL-Tween 80 copolymer was synthesized from ɛ-caprolactone and Tween 80 in the presence of stannous octoate as a catalyst via ring opening polymerization. Two types of nanoparticle formulation were made from commercial PCL and a self-synthesized PCL-Tween 80 copolymer using a modified solvent extraction/evaporation method.
The nanoparticles were found by field emission scanning electron microscopy to have a spherical shape and be 200 nm in diameter. The copolymers could encapsulate 10% of the drug in the nanoparticles and release 34.9% of the encapsulated drug over 28 days. PCL-Tween 80 nanoparticles could be internalized into the cells and had higher cellular uptake than the PCL nanoparticles. The drug-loaded PCL-Tween 80 nanoparticles showed better in vitro cytotoxicity towards C6 cancer cells than commercial Taxotere at the same drug concentration.
Nanoparticles using PCL-Tween 80 copolymer as drug delivery vehicles may have a promising outcome for cancer patients.
International Journal of Nanomedicine 01/2011; 6:2679-88. · 3.13 Impact Factor
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Yufang Zuo,
Jiangxue Wu,
Zumin Xu,
Shiping Yang,
Haijiao Yan,
Li Tan,
Xiangqi Meng,
Xiaofang Ying, Ranyi Liu,
Tiebang Kang,
Wenlin Huang
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ABSTRACT: Nonviral vectors are attractively used for gene therapy owing to their distinctive advantages. Our previous study has demonstrated that transfer of human IFNγ gene into nasopharyngeal carcinoma (NPC) by using a novel nonviral vector, minicircle (mc), under the control of cytomegalovirus (CMV) promoter was effective to inhibit tumor growth. However, therapies based on CMV promoter cannot express the targeted genes in cancer tissues. Previous studies indicated that the development of human NPC was closely associated with Epstein-Barr virus (EBV) and demonstrated the transcriptional enhancer function of oriP when bound by EBV protein. Therefore, the present study is to explore the targeted gene expression and the anti-tumor effect of a novel tumor-specific gene therapeutic system (mc-oriP-IFNγ) in which the transgene expression was under the transcriptional regulation of oriP promoter.
Dual-luciferase reporter assay and ELISA were used to assess the expression of luciferase and IFNγ. WST assay was used to assess the cell proliferation. RT-PCR was used to detect the mRNA level of EBNA1. RNAi was used to knockdown the expression of EBNA1. NPC xenograft models in nude mice were used to investigate the targeted antitumor efficacy of mc-oriP-IFNγ. Immunohistochemistry was used to detect the expression and the activity of the IFNγ in tumor sections. Our results demonstrated that mc-oriP vectors mediated comparable gene expression and anti-proliferative effect in the EBV-positive NPC cell line C666-1 compared to mc-CMV vectors. Furthermore, mc-oriP vectors exhibited much lower killing effects on EBV-negative cell lines compared to mc-CMV vectors. The targeted expression of mc-oriP vectors was inhibited by EBNA1-siRNA in C666-1. This selective expression was corroborated in EBV-positive and -negative tumor models.
This study demonstrates the feasibility of mc-oriP-IFNγ as a safe and highly effective targeted gene therapeutic system for the treatment of EBV positive NPC.
PLoS ONE 01/2011; 6(5):e19407. · 4.09 Impact Factor
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ABSTRACT: AML has a dismal prognosis. It was previously shown that the expression of gene coding for the hyperfusogenic gibbon ape leukemia virus envelope glycoprotein (GALV.fus) can efficiently kill leukemic cells. However, target killing effect of GALV.fus on leukemia cells may be limited. Viral vectors, such as retroviruses and adenoviruses, have been developed to deliver heterologous genes into tumors in vivo, but these vectors have some limitations for gene therapy of leukemia. Another virus that has drawn interest as a gene transfer vector is the Sindbis virus. Sindbis virus efficiently infects human tumor cells through the high-affinity 67 kDa Laminin receptor. We found that Laminin-R was obviously expressed in HL-60 and primary human AML cells, but weakly expressed in K562 cells and blood samples of normal human. So we reasoned that Sindbis-virus-based vectors might be ideal for target gene transfer of GALV.fus to acute myeloid leukemic cell. It was shown that Sindbis virus efficiently transduced human acute myeloid leukemic cells with high expression of Laminin-R and exhibited potent cytopathic potential. What is more, we found that CFU-GMs were significantly reduced after Sindbis virus carrying GALV.fus transduced human primary AML cells. Sindbis virus carrying GALV.fus was active against human AML xenografts in vivo. Taken together, we concluded that Sindbis virus carrying GALV.fus may be an useful strategy for gene therapy of acute myeloid leukemia.
Cancer biology & therapy 03/2010; 9(5):350-7. · 2.64 Impact Factor
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ABSTRACT: Nasopharyngeal carcinoma (NPC) is an endemic malignant disease of the head and neck region with unique features including striking ethnic and geographic variations as well as multifactorial etiology. Previous studies have demonstrated the anticancer properties of genistein, the major soy isoflavonoid, in several human cancer cells such as breast, prostate, colon, gastric, lung, and hepatoma. However, the action of genistein in NPC cells has not been determined. In this study, we investigated the inhibitory effects of genistein on NPC cells and its possible underlying mechanisms. We found that genistein dose-dependently inhibited the proliferation of human NPC cell line CNE2 cells. DNA flow cytometric analysis revealed that 30 to 120 microM genistein induced dramatic G2/M phase arrest in NPC cells. The mRNA expression levels, as shown by gene expression array and quantitative real-time polymerase chain reaction, and the protein expression levels of the cell cycle regulators p21(Cip1) and ATR (Ataxia telangiectasia and Rad3 related) were elevated following genistein treatment. Interestingly, we also observed concomitant induction of p15(Ink4b) in genistein induced inhibitory effects in NPC cells. Moreover, selective estrogen receptor modulators did not affect genistein induced growth inhibition. These findings provide new insights into the potential intervention of NPC with genistein.
Nutrition and Cancer 01/2010; 62(5):641-7. · 2.78 Impact Factor
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Peng Zhao,
Rongcheng Luo,
Jiangxue Wu,
Fajun Xie,
Hongli Li,
Xia Xiao,
Liwu Fu,
Xiaofeng Zhu, Ranyi Liu,
Yinghui Zhu,
Zhihui Liang,
Wenlin Huang
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ABSTRACT: E10A, a replication-defective adenovirus carrying human endostatin gene, has finished Phase I clinical trials for solid cancers. We assessed whether the combination of E10A with docetaxel would enhance antiangiogenic activities and inhibit prostate cancer growth and metastases. Combination use of conditioned medium from prostate cancer cells infected by E10A and docetaxel exerted synergistic inhibition of HUVECs proliferation, migration and tube formation, compared with either agent alone. In prostate cancer s.c. xenograft models, combined therapy resulted in significant tumor growth inhibition and survival improvement. The antitumoral effect was tightly correlated with a remarkable decrease in tumor cell proliferation, microvessel, especially immature vasculature and significant increase in apoptosis induction. Systemic administration of E10A and docetaxel also effectively inhibited orthotopic growth and metastases of prostate cancer and achieved better in vivo antiangiogenic effects than either agent alone. Our data indicate that E10A in combination with docetaxel exert enhanced antiangiogenic activities and inhibit prostate cancer growth and metastases. Therefore, this approach may be an effective treatment for advanced prostate cancer and deserves more extensive investigation.
Journal of Cellular and Molecular Medicine 11/2008; · 4.13 Impact Factor
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ABSTRACT: Viral fusogenic membrane glycoproteins (FMGs) are new therapeutic genes for the control of tumor growth, the cellular mechanisms mediating cell death is non-apoptotic. However, the precise molecular mechanism remains to be elucidated. Here, we showed overexpression of HSP70 in HL-60 cells mediated by Gibbon Ape leukemia virus hyperfusogenic envelope protein (GALV-FMG) inhibited the nuclear translocation of p65, the transcriptive activity of NF-kappaB and prevented the degradation of IkappaB. NF-kappaB may negatively regulate HSP70 expression, which made a positive feed back loop for expression of HSP70. FMG expression in HL-60 cells leaded to the formation of multinucleated syncytia and cell death, the main death mode of cells is necrosis. This form of cell death should be effective in vivo, gene therapy basing on FMG deserve further study for the treatment of AML.
Cancer letters 10/2008; 273(1):114-21. · 4.86 Impact Factor
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ABSTRACT: Endostatin is a potent angiogenic inhibitor that has been approved for the treatment of cancer. However, endostatin is unstable in vitro and difficult to produce in large quantities. Endostatin gene therapy is an alternative to overcome these difficulties by expressing sustained bioactive endostatin in vivo. We previously developed a recombinant replication-defective adenovirus, E10A, which carries the human endostatin gene. Phase I trial of E10A given as a weekly intratumoral injection in adult patients with solid tumors has been finished. The clinical application of endostatin gene therapy was limited by the high cost of large-scale production. In the current study, we found that there was a high level (100mg/L) of endostatin in the fermentation supernatant of 293 cells transfected with Ad/rhEndo. A protocol was developed to purify recombinant endostatin in the fermentation supernatant to a yield of 24mg/L and 98% purity by the use of SP Sepharose FF cation exchange chromatography, Sepharose-heparin Hi Trap affinity chromatography and gel filtration chromatography. The anti-proliferative activity of 293 cell-expressed endostatin (ArhEndo) is comparable to that of yeast-expressed endostatin (YrhEndo). Cell migration assay indicated that ArhEndo is more effective than YrhEndo. Moreover, ArhEndo is of higher stability than YrhEndo. These results suggested that purification of recombinant endostatin from fermentation supernatant provided an economic and available strategy for Ad/rhEndo production.
Protein Expression and Purification 01/2008; 56(2):205-11. · 1.59 Impact Factor
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ABSTRACT: ZD6474 is a vascular endothelial growth factor receptor (VEGFR) and epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor. The present study was undertaken to investigate the direct antiproliferative effect of ZD6474 on human nasopharyngeal carcinoma (NPC) in vitro and the antitumor activity on NPC xenografts in vivo. Results indicated that ZD6474 treatment inhibited EGFR phosphorylation and led to a dose- and time-dependent decrease in NPC cell (CNE-1, CNE-2 and C666-1) proliferation. Further investigation demonstrated G0/G1 cell cycle arrest in all 3 cell lines, which was associated with an upregulation of p21 and/or p27, and downregulation of CDK4, CDK6 and CDK2. ZD6474 treatment also induced apoptosis in CNE-1 and CNE-2 cells. The apoptosis mechanisms involved reduction of Bcl-2 and/or Bcl-XL, induction of Bak and/or Bax, and activation of caspases-3, -9 and/or -8. The in vivo antitumor activity was evaluated in CNE-2 and C666-1 xenografted nude mice. Administration of ZD6474 (25-100 mg/kg/day, once-daily, p.o.) produced a dose-dependent inhibition of tumor growth and prolonged survival in both models. This study suggests that ZD6474 exerts direct antiproliferative effects on NPC cell lines in vitro by inducing G0/G1 arrest and apoptosis, and potent antitumor effects on NPC xenografts in vivo. It indicates that ZD6474 may offer a new and effective treatment for human NPC.
International Journal of Cancer 12/2007; 121(9):2095-104. · 5.44 Impact Factor
