[show abstract][hide abstract] ABSTRACT: Chronic exposure to nickel compounds is associated with increased incidence of certain types of human cancer, including lung and nasal cancers. Despite intensive investigation, the oncogenic processes remain poorly understood. Apoptosis resistance is a key feature for tumor cells to escape physiological surveillance and acquire growth advantage over normal cells. Although NiCl2 exposure induces transformation of human lung epithelial cells, little information is available with regard to its molecular mechanisms, it is also not clear if the transformed cells are apoptosis resistant and tumorigenic. We explored the apoptosis resistance properties of nickel chloride‑transformed human lung epithelial cells and the underlying mechanisms. The results showed that transformed BEAS-2B human lung epithelial cells are resistant to NiCl2-induced apoptosis. They have increased Bcl-2, Bcl-xL and catalase protein levels over the passage matched non‑transformed counterparts. The mechanisms of apoptosis resistance are mitochondria‑mediated and caspase-dependent. Forced overexpression of Bcl-2, Bcl-xL and catalase proteins reduced NiCl2-induced cell death; siRNA‑mediated knockdown of their expression sensitized the cells to nickel-induced apoptosis, suggesting that Bcl-2, Bcl-xl and catalase protein expression plays a critical role in apoptosis resistance. Akt also participates in this process, as its overexpression increases Bcl-xL protein expression levels and attenuates NiCl2-induced apoptosis. Furthermore, transformed cells are tumorigenic in a xenograft model. Together, these results demonstrate that nickel-transformed cells are apoptosis‑resistant and tumorigenic. Increased expression of Bcl-2, Bcl-xL and catalase proteins are important mechanisms contributing to transformed cell oncogenic properties.
International Journal of Oncology 07/2013; · 2.66 Impact Factor
[show abstract][hide abstract] ABSTRACT: BACKGROUND: Adoptive transfer of chimeric antigen receptor (CAR)-modified T cells appears to be a promising immunotherapeutic strategy. CAR combines the specificity of antibody and cytotoxicity of cytotoxic T lymphocytes, enhancing T cells' ability to specifically target antigens and to effectively kill cancer cells. Recent efforts have been made to integrate the costimulatory signals in the CAR to improve the antitumor efficacy. Epidermal growth factor receptor variant III (EGFRvIII) is an attractive therapeutic target as it frequently expresses in glioma and many other types of cancers. Our current study aimed to investigate the specific and efficient antitumor effect of T cells modified with CAR containing inducible costimulator (ICOS) signaling domain. METHODS: A second generation of EGFRvIII/CAR was generated and it contained the EGFRvIII single chain variable fragment, ICOS signaling domain and CD3zeta chain. Lentiviral EGFRvIII/CAR was prepared and human CD3+ T cells were infected by lentivirus encoding EGFRvIII/CAR. The expression of EGFRvIII/CAR on CD3+ T cells was confirmed by flow cytometry and Western blot. The functions of EGFRvIII/CAR+ T cells were evaluated using in vitro and in vivo methods including cytotoxicity assay, cytokine release assay and xenograft tumor mouse model. RESULTS: Chimeric EGFRvIIIscFv-ICOS-CD3zeta (EGFRvIII/CAR) was constructed and lentiviral EGFRvIII/CAR were made to titer of 106 TU/ml. The transduction efficiency of lentiviral EGFRvIII/CAR on T cells reached around 70% and expression of EGFRvIII/CAR protein was verified by immunoblotting as a band of about 57 kDa. Four hour 51Cr release assays demonstrated specific and efficient cytotoxicity of EGFRvIII/CAR+ T cells against EGFRvIII expressing U87 cells. A robust increase in the IFN-gamma secretion was detected in the co-culture supernatant of the EGFRvIII/CAR+ T cells and the EGFRvIII expressing U87 cells. Intravenous and intratumor injection of EGFRvIII/CAR+ T cells inhibited the in vivo growth of the EGFRvIII expressing glioma cells. CONCLUSIONS: Our study demonstrates that the EGFRvIII/CAR-modified T cells can destroy glioma cells efficiently in an EGFRvIII specific manner and release IFN-gamma in an antigen dependent manner. The specific recognition and effective killing activity of the EGFRvIII-directed T cells with ICOS signaling domain lays a foundation for us to employ such approach in future cancer treatment.
[show abstract][hide abstract] ABSTRACT: To investigate a baculovirus insect cell system for expressing an interferon alpha 2b (IFNa2b)/immunoglobulin G-4 (IgG4) Fc fusion protein, which has long-acting antiviral effects. Human IFNa2b and IgG4 Fc cDNAs were generated by molecular cloning and inserted into a baculovirus shuttle vector, which was then transposed into the DH10 Bac strain to form recombinant Bacmid-IFN/Fc. The Bacmid-IFN/Fc was transfected into High five insect cells, and expression of the IFN/Fc fusion protein was detected by Western blotting and its biological activity was assessed by the cytopathic effect inhibition method. The IFNa2b and IgG4 Fc cDNA fragments were successfully amplified by RT-PCR using human peripheral lymphocytes. After cloning into the baculovirus shuttle vector, pFastBac1, and transforming into DH10 Bac competent cells, screening identified positive clones carrying the recombinant Bacmid-IFN/Fc. A Bacmid-IFN/Fc clone was successfully transfected into the High five insect cells and packaged into the baculovirus for expression of the IFN/Fc fusion protein. Western blotting revealed that the fusion protein expression was specific, and yielded a protein of 45 kD in size. The in vitro antiviral activity of the IFN/Fc fusion protein was 580 IU/mL. A novel IFN/Fc fusion protein was successfully generated using a baculovirus insect cell system, which may prove useful for providing future experimental data for development of a new long-acting interferon to treat chronic viral hepatitis.
Zhonghua gan zang bing za zhi = Zhonghua ganzangbing zazhi = Chinese journal of hepatology 08/2012; 20(8):617-20.
[show abstract][hide abstract] ABSTRACT: To study the relationship between COX-2 gene and hereditariness to Nonalcoholic fatty liver disease by detecting single nucleotide polymorphisms in the promoter of COX-2 gene.
Genotypes of 200 case patients with NAFLD and 206 control subjects were examined by polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP). The DNA samples were extracted from the peripheral blood of all subjects.
Two SNPs, -1195G more than A and -765 G more than C, were identified with frequencies of variant alleles 54% and 5% in patients with NAFLD and 48% and 2% in control, respectively. A case-control analysis revealed a 1.13-fold (95% CI = 1.01-2.46) and a 2.35-fold (95% CI = 1.17-3.65) excess risk of developing NAFLD for -1195AA or -765CG genotype carriers compared with noncarriers. Compared with G-1195-G-765 containing haplotype, a greater risk of developing NAFLD was observed for A-1195-G-765 (OR =1.42; 95% CI =1.11-1.63) and A-1195-C-765 (OR = 4.24; 95% CI =1.72-14.22) containing haplotypes. A greater risk of developing NAFLD was observed for A-1195 and C-765 containing haplotype compared with other haplotype, suggesting an interaction between the -1195A and -765C in the context of haplotype.
These findings suggest that genetic variants in the COX-2 promoter may play an important role in mediating susceptibility to developing NAFLD in a Chinese population. -1195G more than A and -765G more than C in promoter region of Cyclooxygenase-2 gene, whose single nucleotide polymorphisms are related with development of NAFLD, are the significance factors of the susceptibility of NAFLD.
Zhonghua gan zang bing za zhi = Zhonghua ganzangbing zazhi = Chinese journal of hepatology 10/2010; 18(10):773-7.
[show abstract][hide abstract] ABSTRACT: To study the action of hepatitis virus infection-associated genes at transcription level during liver regeneration (LR).
Hepatitis virus infection-associated genes were obtained by collecting the data from databases and retrieving the correlated articles, and their expression changes in the regenerating rat liver were detected with the rat genome 230 2.0 array.
Eighty-eight genes were found to be associated with liver regeneration. The number of genes initially and totally expressed during initial LR [0.5-4 h after partial hepatectomy (PH)], transition from G0 to G1 (4-6 h after PH), cell proliferation (6-66 h after PH), cell differentiation and reorganization of structure-function (66-168 h after PH) was 37, 8, 48, 3 and 37, 26, 80, 57, respectively, indicating that the genes were mainly triggered at the early stage of LR (0.5-4 h after PH), and worked at different phases. These genes were classified into 5 types according to their expression similarity, namely 37 up-regulated, 9 predominantly up-regulated, 34 down-regulated, 6 predominantly down-regulated and 2 up/down-regulated genes. Their total up- and down-regulation frequencies were 359 and 149 during LR, indicating that the expression of most genes was enhanced, while the expression of a small number of genes was attenuated during LR. According to time relevance, they were classified into 12 groups (0.5 and 1 h, 2 and 4 h, 6 h, 8 and 12 h, 16 and 96 h, 18 and 24 h, 30 and 42 h, 36 and 48 h, 54 and 60 h, 66 and 72 h, 120 and 144 h, 168 h), demonstrating that the cellular physiological and biochemical activities during LR were fluctuated. According to expression changes of the genes, their expression patterns were classified into 23 types, suggesting that the cellular physiological and biochemical activities during LR were diverse and complicated.
The anti-virus infection capacity of regenerating liver can be enhanced and 88 genes play an important role in LR.
World Journal of Gastroenterology 01/2007; 12(47):7626-34. · 2.55 Impact Factor
[show abstract][hide abstract] ABSTRACT: To study the effectiveness of an artificial liver support system.
Thirty-two patients with medicamentous liver insufficiency were treated with an artificial liver support system in addition to the routine medicinal therapy. Thirty patients treated with routine medicinal therapy only served as controls.
The clinical symptoms (e.g. hepatic encephalopathy) and the laboratory indices (serum total bilirubin and prothrombin time) of the treatment group patients were obviously improved compared with those of the control group patients (P < 0.05). The cure rate and hospitalization days were 90.6% (26/32) and 47 days respectively in the treatment group, and 43.3% (13/30) and 72 days in the control group (P < 0.05).
Using an artificial liver support system combined with routine medicinal therapy is more effective than using medication alone.
Zhonghua gan zang bing za zhi = Zhonghua ganzangbing zazhi = Chinese journal of hepatology 11/2005; 13(11):836-8.
[show abstract][hide abstract] ABSTRACT: A I M : T o i n v e s t i g a t e t h e g e n e e x p r e s s i o n profiles in tissues of normal human liver, chronic hepatitis B, cirrhosis and hepatocellular carcinoma (HCC) by oligonucletide chip, and to screen HCC-related genes. METHODS: The total RNA was extracted and reverse transcribed into double-strand cDNA, and then transcribed into biotin-labled cRNA target probes. The probes were hybridized with oligonucleotide chip containing 19378 genes re- spectively. Subsequently, the signal images were scanned by gene Scanner 3000 and analyzed with GenePix Pro 3.0 software. RESULTS: Eighty-one genes differentially ex- pressed among tissues of chronic hepatitis B, cir- rhosis and HCC were screened out in the gene expression profiles. Of the 81 genes, 53 genes were consistently up-regulated, while 28 genes were consistently down-regulated. CONCLUSION: The oligonucleotide chip of gene expression profile is powerful for screen- ing HCC-related genes. Our results indicate that multiple genes take part in the carcinogenesis of HCC.