To investigate whether transcription of hepatitis B virus (HBV) gene occurs in human sperm, total RNA was extracted from sperm of patients with chronic HBV infection (test-1), from donor sperm transfected with a plasmid containing the full-length HBV genome (test-2), and from nontransfected donor sperm (control), used as the template for reverse transcription-polymerase chain reaction (RT-PCR). Positive bands for HBV DNA were observed in the test groups but not in the control. Next, to identify the role of host genes in regulating viral gene transcription in sperm, total RNA was extracted from 2-cell embryos derived from hamster oocytes fertilized in vitro by HBV-transfected (test) or nontransfected (control) human sperm and successively subjected to SMART-PCR, suppression subtractive hybridization, T/A cloning, bacterial amplification, microarray hybridization, sequencing and the Basic Local Alignment Search Tool (BLAST) search to isolate differentially expressed genes. Twenty-nine sequences showing significant identity to five human gene families were identified, with chorionic somatomammotropin hormone 2 (CSH2), eukaryotic translation initiation factor 4 gamma 2 (EIF4G2), pterin-4 alpha-carbinolamine dehydratase 2 (PCBD2), pregnancy-specific beta-1-glycoprotein 4 (PSG4) and titin (TTN) selected to represent target genes. Using real-time quantitative RT-PCR (qRT-PCR), when CSH2 and PCBD2 (or EIF4G2, PSG4 and TTN) were silenced by RNA interference, transcriptional levels of HBV s and x genes significantly decreased (or increased) (P < 0.05). Silencing of a control gene in sperm did not significantly change transcription of HBV s and x genes (P > 0.05). This study provides the first experimental evidence that transcription of HBV genes occurs in human sperm and is regulated by host genes.
Animals ; Connectin/genetics* ; Cricetinae ; Eukaryotic Initiation Factor-4G/genetics* ; Gene Expression Regulation/genetics* ; Gene Silencing ; Growth Hormone/genetics* ; Hepatitis B Surface Antigens/genetics* ; Hepatitis B virus/genetics* ; Hepatitis B, Chronic/virology* ; Humans ; Hydro-Lyases/metabolism* ; Male ; Pregnancy-Specific beta 1-Glycoproteins/genetics* ; RNA, Viral/analysis* ; Spermatozoa/virology* ; Trans-Activators/genetics* ; Transcription, Genetic ; Transfection ; Viral Regulatory and Accessory Proteins

No abstract available.
Base Sequence ; Bone Marrow/pathology ; Child, Preschool ; Chromosomes, Human, Pair 12 ; Chromosomes, Human, Pair 17 ; Female ; Gene Rearrangement ; Humans ; Karyotype ; Oncogene Proteins, Fusion/genetics ; Precursor Cell Lymphoblastic Leukemia-Lymphoma/*diagnosis/genetics ; Sequence Analysis, DNA ; TATA-Binding Protein Associated Factors/*genetics ; Trans-Activators/*genetics ; *Translocation, Genetic

To study the effect of micro (mi)RNA on cellular proliferation induced by hepatitis B x protein, HBx, in human liver cells and to investigate the underlying molecular mechanism of this cancer-related effect. The human L02 hepatocyte cell line was stably transfected with HBx (L02/HBx) or an HBx mutant (L02/HBx-d382) that induces higher levels of cellular proliferation. The differential miRNA expression profiles were determined by microarray analysis and confirmed by real-time PCR. Two miRNAs, miR-338-3p and miR-551b, that were found to be significantly down-regulated in the L02/HBx-d382 cells were selected for further study and transfected individually into cells using the lipofectamine procedure. The cell survival rate was analyzed by MTT assay, and cell cycles were assessed by flow cytometry. Expressions of cyclinD1, cyclinG1, and E2F1 were assessed by real-time PCR and Western blotting. Compared with the microarray miRNA profile of L02/pcDNA3.0 cells, six miRNAs were up-regulated and five miRNAs were down-regulated in the L02/HBx-d382 cells, while four miRNAs were up-regulated and 12 were down-regulated in the L02/HBx cells. The microarray results were consistent with real-time PCR results. Transfection of miR-338-3p and miR-551b significantly inhibited the cell survival rates (P less than 0.001) and induced G0/G1 phase cycle arrest. According to MTT results: for L02/HBx-d382 cells, compared with lipofectamine or non-transfected (NC) controls, the t value of miR-338-3p was 10.402, 9.133 and the t value of miR-551b was 8.763, 7.403; for L02/HBx cells, compared with lipofectamine or NC controls, the t value of miR-338-3p was 9.105, 8.074 and the t value of miR-551b was 7.673, 7.52. According to flow cytometry results: for L02/HBx-d382 cells, compared with lipofectamine or NC controls, the t value of miR-338-3p was 12.173, 11.107 and the t value of miR-551b was 15.364, 13.377; for L02/HBx cells, compared with lipofectamine or NC controls, the t value of miR-338-3p was 15.416, 13.378, and the t value of miR-551b was 13.276, 13.109. The protein levels of cyclinD1, cyclinG1, and E2F1 were significantly reduced by both miR-338-3p and miR-551b ( P less than 0.001). For L02/HBx-d382 cells, compared with lipofectamine or NC controls: E2F1 had t = 11.132, 10.031 and 12.017, 10.973, respectively; cyclinD1 had t = 15.654, 15.013 and 15.447, 14.733, respectively; cyclinG1 had t = 8.017, 7.661 and 7.402, 7.417, respectively. For L02/HBx cells, compared with lipofectamine or NC controls: E2F1 had t = 14.244, 13.331 and 15.022, 14.468, respectively; cyclinD1 had t = 8.695, 8.137 and 7.877, 7.503, respectively; cyclinG1 had t = 7.73, 7.471 and 7.596, 7.41, respectively. In contrast, the mRNA levels for E2F1, cyclinD1, and cylcinG1 showed no significant differences between the miRNA transfected cells and controls. Wild-type HBx and the high proliferation-inducing mutant HBx can influence the miRNA expression profile of L02 cells. HBx down-regulates miR-338-3p and miR-551b in L02 cells, and the high proliferation-inducing mutant has a more robust effect. The mechanism of miR-338-3p- or miR-551b-mediated cell growth inhibition appears to be related to the direct modulation of cyclinD1, cyclinG1, and E2F1.
Blotting, Western ; Carcinoma, Hepatocellular ; genetics ; metabolism ; pathology ; Cell Cycle ; Cell Line ; Cell Proliferation ; Cyclins ; genetics ; metabolism ; Gene Expression Regulation, Neoplastic ; Genes, Viral ; Hepatitis B virus ; genetics ; metabolism ; Hepatocytes ; metabolism ; pathology ; Humans ; Liver Neoplasms ; genetics ; metabolism ; pathology ; MicroRNAs ; genetics ; metabolism ; Mutation ; Oligonucleotide Array Sequence Analysis ; RNA, Messenger ; genetics ; Real-Time Polymerase Chain Reaction ; Trans-Activators ; genetics ; metabolism ; Transfection

Exosomes are small membrane vesicles secreted from various types of cells. Tumor-derived exosomes contain MHC class I molecules and tumor-specific antigens, receiving attention as a potential cancer vaccine. For induction of efficient anti-tumor immunity, CD4+ helper T cells are required, which recognize appropriate MHC class II-peptide complexes. In this study, we have established an MHC class II molecule-expressing B16F1 murine melanoma cell line (B16F1-CIITA) by transduction of the CIITA (Class II transactivator) gene. Exosomes from B16-CII cells (CIITA-Exo) contained a high amount of MHC class II as well as a tumor antigen TRP2. When loaded on dendritic cells (DCs), CIITA-Exo induced the increased expression of MHC class II molecules and CD86 than the exosomes from the parental cells (Exo). In vitro assays using co-culture of immunized splenocytes and exosome-loaded DCs demonstrated that CIITA-Exo enhanced the splenocyte proliferation and IL-2 secretion. Consistently, compared to B16-Exo, CIITA-Exo induced the increased mRNA levels of inflammatory cytokines such as TNF-alpha, chemokine receptor CCR7 and the production of Th1-polarizing cytokine IL-12. A tumor preventive model showed that CIITA-Exo significantly inhibited tumor growth in a dose-dependent manner. Ex vivo assays using immunized mice demonstrated that CIITA-Exo induced a higher amount of Th1-polarized immune responses such as Th1-type IgG2a antibodies and IFN-gamma cytokine as well as TRP2-specific CD8+ T cells. A tumor therapeutic model delayed effects of tumor growth by CIITA-Exo. These findings indicate that CIITA-Exo are more efficient as compared to parental Exo to induce anti-tumor immune responses, suggesting a potential role of MHC class II-containing tumor exosomes as an efficient cancer vaccine.
Animals ; Cancer Vaccines/genetics/immunology ; Cell Line, Tumor ; Cell Proliferation ; Dendritic Cells/immunology ; Exosomes/genetics/*metabolism ; Gene Expression Regulation ; Gene Transfer Techniques ; Immunity, Cellular/immunology ; Immunity, Humoral/immunology ; Immunotherapy ; Lymphocyte Activation/immunology ; Melanoma, Experimental/mortality/pathology/*physiopathology ; Mice ; Mice, Inbred C57BL ; Nuclear Proteins/*genetics/*metabolism ; Survival Analysis ; T-Lymphocytes/immunology/metabolism ; Trans-Activators/*genetics/*metabolism ; Transduction, Genetic

BACKGROUNDUncoupling protein (UCP) 2 is related to the dysfunction of beta cells induced by fatty acids. However, whether UCP2 has similar effects on alpha cell is still not clear. This study aimed to investigate the effects of UCP2 and its possible mechanisms in lipotoxicity-induced dysfunction of pancreatic alpha cells.

METHODSThe alpha TC1-6 cells were used in this study to evaluate the effects of palmitate and/or UCP2 inhibit factors on the glucagon secretory function, glucagon content, the glucagon mRNA level and the nitrotyrosine level in the supernatant. Meantime, the expression levels of UCP2 and peroxisome proliferator-activated receptor-γ coactivator-1 alpha (PGC-1 alpha) were measured by real-time reverse transcription polymerase chain reaction (RT-PCR) and Western blotting. Furthermore, the possible relationship between UCP2 and insulin signal transduction pathway was analyzed.

RESULTSPalmitate stimulated alpha cell glucagon secretion and the expression of UCP2 and PGC-1 alpha, which could be partially decreased by the inhibition of UCP2. Palmitate increased nitrotyrosine level and suppressed insulin signal transduction pathway in alpha cells. Inhibition of UCP2 influenced the effects of free fatty acid on alpha cells and may relate to glucagon secretion.

CONCLUSIONUCP2 played an important role on alpha cell dysfunction induced by free fatty acid in vitro, which may be related to its effects on oxidative stress and insulin signal transduction pathway.

Animals ; Cells, Cultured ; Glucagon ; secretion ; Glucagon-Secreting Cells ; drug effects ; physiology ; Insulin ; pharmacology ; Insulin Receptor Substrate Proteins ; metabolism ; Ion Channels ; genetics ; physiology ; Iridoid Glycosides ; pharmacology ; Iridoids ; Mice ; Mitochondrial Proteins ; genetics ; physiology ; Oxidative Stress ; Palmitic Acid ; toxicity ; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha ; Phosphorylation ; RNA, Messenger ; analysis ; Signal Transduction ; Trans-Activators ; genetics ; physiology ; Transcription Factors ; Tyrosine ; analogs & derivatives ; metabolism ; Uncoupling Protein 2

BACKGROUNDADULT syndrome (acro-dermato-ungual-lacrimal-tooth syndrome) is a rare ectodermal dysplasia disorder known as autosomal dominant inheritance. Recent studies have linked p63 gene mutation to the development of this disease. However, the genetic characteristics of ADULT syndrome were still not well understood.

METHODSMutation analysis of p63 gene in the first Chinese ADULT syndrome family was performed using direct DNA sequencing.

RESULTSThe sequence analysis of exon 8 of p63 gene disclosed a heterozygous G>A substitution at nucleotide 893 (R298Q) in the proband. In addition, a single nucleotide polymorphism (SNP) rs16864880 in the downstream flanking region (DFR) of p63 exon 8 was also identified in this family. The proband and the paternal side including her father exhibited the C/G genotype at this position. The C/G variant frequency in the paternal was significantly higher as compared with the maternal (6/10 vs 0/6, P = 0.034).

CONCLUSIONSADULT syndrome may be caused by the p63 gene mutation, and it might have closer genetic association with the paternal side in this family.

Adult ; Asian Continental Ancestry Group ; genetics ; DNA Mutational Analysis ; Ectodermal Dysplasia ; genetics ; Female ; Genetic Predisposition to Disease ; Humans ; Male ; Models, Molecular ; Mutation ; genetics ; Pedigree ; Protein Structure, Tertiary ; Trans-Activators ; chemistry ; genetics ; Transcription Factors ; Tumor Suppressor Proteins ; chemistry ; genetics

OBJECTIVETo investigate whether there were particular HBx gene mutations associated with hepatocellular carcinoma (HCC) development in patients.

METHODSThe HBx genes were examined in 51 paraffin-embedded tumor tissue samples from patients with HCC and 25 serum samples from HBV carriers from southern China by nested polymerase chain reaction (PCR), single-stranded conformational polymorphism analysis, heteroduplex analysis and DNA sequencing. The HBx genes with deletion variations (HBx-d382, HBx-d431) from tumor tissues were cloned and transfected into QSG7701 cells. Then, the biological characteristics of the transfected cells were analyzed in nude mice by MTT assay, soft agar colony formation assay, flow cytometry and xenografting.

RESULTSDeletion mutation and point mutation were found in the HBx genes of HCC tumor tissues, and there were some differences between the HBx gene mutations in genotype B and those in genotype C. More mutations were found in genotype C than those in genotype B (t=-2.522, P < 0.05), but the deletion variations (HBx-d382, HBx-d431) were detected in genotype B HBV from HCC liver tissues. The HBx genes with deletion variations (HBx-d382, HBx-d431) were recombinant with pcDNA3 and transfected into QSG7701 cell lines successfully, which established four permanent transfected QSG7701 cell lines, including pcDNA3/HBx-d382/QSG7701, pcDNA3/HBx-d431/QSG7701, pcDNA3/HBx/QSG7701, and pcDNA3/QSG7701. pcDNA3/HBx-d382/QSG7701 and pcDNA3/HBx-d431/QSG7701 grew faster and had more potential colony formative activity than those of pcDNA3/QSG7701. Moreover, pcDNA3/HBx-d382/QSG7701 and pcDNA3/HBx-431/QSG7701 cells inoculated in nude mice produced tumors more rapidly than those of pcDNA3/HBx/QSG7701, and pcDNA3/QSG7701. The volumes of the tumors in nude mice were also obviously larger in pcDNA3/HBx-d382 and pcDNA3/HBx-d431 groups than those in pcDNA3/HBx/QSG7701 and pcDNA3/QSG7701 groups.

CONCLUSIONOur results suggest that HBx gene mutations occur frequently in HCC tissues, and the deletion at nt382-400 of the HBx gene might play a role in carcinogenesis of HCC in southern China.

Adult ; Aged ; Animals ; Base Sequence ; Carcinoma, Hepatocellular ; virology ; Cell Line, Tumor ; DNA, Viral ; genetics ; Female ; Hepatitis B Surface Antigens ; blood ; Hepatitis B virus ; genetics ; Humans ; Liver Neoplasms ; virology ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Middle Aged ; Point Mutation ; Polymorphism, Single-Stranded Conformational ; Sequence Analysis, DNA ; Sequence Deletion ; Trans-Activators ; genetics ; Transfection

BACKGROUNDHepatitis B virus (HBV) X protein (HBx) and p53 could mutually down-regulate at transcriptional level and HBx could bind with p53 protein within its transactivation domain and inhibit the function of p53 protein. In recent years, effects of arsenic trioxide (As2O3) on the expression of p53 protein have been widely studied, while little is known about the activity of p53 protein. This study was undertaken to delineate the effect of HBV X gene and As2O3 on p53 protein expression (level and activity) in HepG2 cells by small hairpin RNA (shRNA)-mediated RNA interference (RNAi) technique.

METHODSCell line HepG2 and cells with stable expression of HBV X gene (HepG2-X) were treated with 2 micromol/L As2O3, with corresponding untreated cells serving as controls. Cell lysates and nuclear extracts were extracted. Total level and the relative activity of p53 protein were detected by modified enzyme-linked immunosorbent assay (ELISA). HBV X gene sequence-specific shRNA expression vector (pXi-1 and pXi-2) and sequence-unrelated control (pXi-3) were transfected into HepG2-X. Single cell clone with stable expression of shRNA was selected and exposed to propagating culture. The effect of As2O3 on p53 protein expression and activity was re-observed.

RESULTSTotal p53 protein level was up-regulated and its relative activity ratio was enhanced by As2O3 in HepG2 and HepG2-X cells. The total p53 protein level induced by As2O3 was up-regulated by HBV X gene expression, while its relative activity was significantly suppressed. The suppression was removed after HBV X gene expression was repressed by shRNA.

CONCLUSIONSAs2O3 up-regulates p53 protein expression and enhance its activity. HBV X up-regulates As2O3 induced-p53 protein expression while suppresses its activity.

Arsenicals ; pharmacology ; Cell Line, Tumor ; Enzyme-Linked Immunosorbent Assay ; Humans ; Oxides ; pharmacology ; RNA Interference ; Trans-Activators ; genetics ; Tumor Suppressor Protein p53 ; analysis

INTRODUCTIONLong QT syndrome (LQTS), an inherited cardiac arrhythmia, is a disorder of ventricular repolarisation characterised by electrocardiographic abnormalities and the onset of torsades de pointes leading to syncope and sudden death. Genetic polymorphisms in 5 well-characterised cardiac ion channel genes have been identified to be responsible for the disorder. The aim of this study is to identify disease-causing mutations in these candidate genes in a LQTS family.

MATERIALS AND METHODSThe present study systematically screens the coding region of the LQTS-associated genes (KCNQ1, HERG, KCNE1, KCNE2 and SCN5A) for mutations using DNA sequencing analysis.

RESULTSThe mutational analysis revealed 7 synonymous and 2 non-synonymous polymorphisms in the 5 ion channel genes screened.

CONCLUSIONWe did not identify any clear identifiable genetic marker causative of LQTS, suggesting the existence of LQTS-associated genes awaiting discovery.

Adolescent ; Adult ; Child ; DNA Mutational Analysis ; ERG1 Potassium Channel ; Ether-A-Go-Go Potassium Channels ; analysis ; genetics ; Female ; Frameshift Mutation ; Humans ; KCNQ1 Potassium Channel ; analysis ; genetics ; Long QT Syndrome ; genetics ; Male ; Middle Aged ; Muscle Proteins ; analysis ; genetics ; NAV1.5 Voltage-Gated Sodium Channel ; Polymorphism, Genetic ; genetics ; Potassium Channels, Voltage-Gated ; analysis ; genetics ; Sodium Channels ; analysis ; genetics ; Trans-Activators

Animals ; Glucose ; pharmacology ; Homeodomain Proteins ; analysis ; genetics ; physiology ; Immunohistochemistry ; Insulin ; secretion ; Male ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Trans-Activators ; analysis ; genetics ; physiology