The influence of ESR1 rs9340799 and ESR2 rs1256049 polymorphisms on prostate cancer risk.

Estrogen receptor 1 (ESR1) and estrogen receptor 2 (ESR2) may play a role in the development of prostate cancer. Many studies focused on ESR1 rs9340799 and ESR2 rs1256049 polymorphisms to explore associations with prostate cancer risk. These studies showed inconsistent and conflicting results. The aim of this meta-analysis was to investigate the pooled association of ESR1 rs9340799 and ESR2 rs1256049 polymorphisms with prostate cancer risk. A systematic literature search was conducted to identify related studies (up to February 2014) in several online databases including PubMed, Google Scholar, CNKI and Wanfang online libraries. A total of 16 eligible articles were enrolled in this updated meta-analysis. The result suggested that ESR1 rs9340799 polymorphism was significantly associated with prostate cancer in overall populations (GG+GA vs. AA: P = 0.002; G vs. A: P = 0.004), Caucasians (GG+GA vs. AA: P = 0.008; G vs. A: P = 0.016) and Africans (GG+GA vs. AA: P = 0.005; G vs. A: P = 0.006), but not in Asians (GG+GA vs. AA: P = 0.462; G vs. A: P = 0.665). The result also showed that there was a significant association between ESR2 rs1256049 polymorphism and prostate cancer in Caucasians (AA+AG vs. GG: P = 0.016; A vs. G: P = 0.005), but no association in overall populations (AA+AG vs. GG: P = 0.826; A vs. G: P = 0.478), Asians (AA+AG vs. GG: P = 0.177; A vs. G: P = 0.703) and Africans (AA+AG vs. GG: P = 0.847; A vs. G: P = 0.707). The cumulative meta-analysis and sensitivity analysis showed the results were robust. In conclusion, this meta-analysis indicated that ESR1 rs9340799 polymorphism was associated with prostate cancer risk in overall populations, Caucasians and Africans, while ESR2 rs1256049 polymorphism was associated with prostate cancer risk in Caucasians. However, the biological mechanisms need to be further investigated.

A vaccinia replication system for producing recombinant hepatitis C virus.

AIM: To develop a cell culture system capable of producing high titer hepatitis C virus (HCV) stocks with recombinant vaccinia viruses as helpers. METHODS: Two plasmids were used for the generation of recombinant HCV: one containing the full-length HCV cDNA cloned between T7 promoter and T7 terminator of pOCUS-T7 vector, and the other containing the HCV polyprotein open reading frame (ORF) directly linked to a vaccinia late promoter in PSC59. These two plasmids were co-transfected into BHK21 cells, which were then infected with vTF7-3 recombinant vaccinia helper viruses. RESULTS: After 5 d of incubation, approximately 3.6X10(7) copies of HCV RNA were present per milliliter of cell culture supernatant, as detected by fluorescence quantitative RT-PCR (FQ-PCR). The yield of recombinant HCV using this cell system increased 100- to 1 000- fold compared to in vitro- transcribed HCV genomic RNA or selective subgenomic HCV RNA molecule method. CONCLUSION: This cell culture system is capable of producing high titer recombinant HCV.

[Establishment and identification of recombinant NS-1 cell strain that stably expresses chimeric HBc containing HBV multiepitope short peptides].

OBJECTIVE: To establish recombinant NS-1 cell strain that is capable of stable expression of chimeric HBc particle containing HBV multi epitope short peptides. METHODS: The recombinant plasmid, pHBc-Mep, was transfected into NS-1 cells via Lipofectamine, and the recombinant cell strain was screened with G418 and subclone screening. The expression products of the cells were examined by RT-PCR, ELISA, indirect immunofluorescence assay (IFA) and Western blotting. RESULTS: The results of RT-PCR, ELISA, IFA and Western blotting demonstrated that the recombinant protein HBc-Mep was expressed in the screened cells after continuous cloning for 3 times, but not in cells transfected with pcDNA3.1 or nontransfected cells. CONCLUSION: The recombinant cell strain stably expressing chimeric HBc particle containing multi epitope short peptides of HBV, designated as NS/HBc-Mep, has been established successfully.

[Cloning and expression of hepatitis C core protein gene].

OBJECTIVE: To express hepatitis C virus (HCV) core protein gene fragment in E. coli. METHODS: A fragment of HCV core gene sequence 357 bp in length was amplified by PCR, digested with EcoRI+Hind III and inserted to the plasmid vector pET-32a to construct recombinant HCVc/pET-32a plasmid, which was transformed into E.coli BL-21 and induced by IPTG for its expression. The expressed proteins obtained were identified by SDS-PAGE and Western blotting. RESULTS: The core sequence of HCV was amplified and after IPTG induction, a fusion protein of 32,000 was resulted exhibiting specific reaction with HCV-positive serum and high antigenicity. CONCLUSION: It is possible to efficiently express HCV core protein in E.coli.

[Cloning of hepatitis C virus open reading frame sequence and non structural protein expressions of the virus].

OBJECTIVE: To induce the expressions of the constituent proteins of hepatitis C virus (HCV) using a vaccinia virus expression system. METHODS: The open reading frame (ORF) sequence encoding HCV large polyprotein precursor was cloned into a vaccinia virus promoter to construct the recombinant plasmid pVHCV, which was subsequently used, along with a control plasmid (pSC59) in a parallel experiment, to transfect BHK21 cells via Lipofectamine 2000 reagent, followed by infection of the cells with vTF7-3 vaccinia viruses. After a 48-h culture, the expressions of HCV nonstructural proteins NS3 and NS5a in the cells were detected using Western blotting and immunofluorescence assay. RESULTS: Western blotting analysis presented the nonstructural proteins NS3 and NS5a detected in pVHCV-transfected BKH21 cells as two bands with molecular weights of 70,000 and 56,000, respectively. In the immunofluorescence assay, intense granular fluorescence signal was detected in the cytoplasm of pVHCV-transfected cells, irrespective of the use of either NS3- or NS5a- specific mouse monoclonal antibody. CONCLUSION: HCV nonstructural proteins NS3 and NS5a can be expressed in BKH21 cells.

[Preparation and identification of phage-displayed ICAM-1-mimic peptide].

AIM: To obtain bioactive ICAM-1 mimetic peptide. METHODS: Phages displaying P1 and P2 were prepared by phage amplication and PEG precipitation. The binding between phage-displayed peptides and anti-ICAM-1 mAb 15.2 was evaluated by sandwich ELISA and competitive ELISA. Bioactivities of P1 and P2 was detected by immunohistochemical staining. RESULTS: Phage-displayed peptides P1 and P2 could specifically bind to mAb 15.2, and the binding could be competitively inhibited by ICAM-1. Immunohistochemical staining showed that P1 and P2 could mimic the binding of ICAM-1 to its receptor LFA-1. CONCLUSION: Phage-displayed peptides P1 and P2 are bioactive just as native ICAM-1.