OBJECTIVETo construct a recombinant lentiviral vector that stably express hepatocyte nuclear factor 6 (HNF6) in colorectal cancer cell line and examine its effects on the invasive ability of SW620 cells.

METHODSThe lentiviral vector pLeno-DCE-HA-HNF6 was constructed and transfected into 293T cells. The supernatant containing the lentivirus particles was harvested to determine the virus titer. A stable cell line was established by infecting SW620 cells with the lentivirus particles, and the transfection efficiency was examined by fluorescence microscopy and flow cytometry. The invasion ability of the transfected SW620-HNF6 cells was assessed by wound healing and transwell assays.

RESULTSThe recombinant lentiviral vector was correctly constructed and verified by sequencing. SW620-HNF6 cell line with stable HNF6 expression was established successfully, and the transfection efficiency reached 82.3%. Western blotting and quantitative PCR demonstrated significantly upregulated HNF6 expression in SW620-HNF6 cells, which showed obviously suppressed invasive ability in wound healing and transwell assays.

CONCLUSIONWe have successfully established a colorectal cancer cell line SW620-HNF6 stably expressing HNF6, which shows a lowered migration activity in vitro.

Cell Line, Tumor ; Cell Movement ; Colorectal Neoplasms ; metabolism ; pathology ; Genetic Vectors ; genetics ; Hepatocyte Nuclear Factor 6 ; biosynthesis ; genetics ; Humans ; Lentivirus ; genetics ; metabolism ; Neoplasm Invasiveness ; Neoplasm Metastasis ; Recombinant Proteins ; biosynthesis ; genetics ; Transfection

We compared the efficiency of cloning goat using human lactoferrin (hLF) with genetically modified donor cells marked by single (Neo(r)) or double (Neo(r)/GFP) markers. Single marker expression vector (pBLC14) or dual markers expression vector (pAPLM) was delivered to goat fetal fibroblasts (GFF), and then the transgenic GFF was used as donor cells to produce transgenic goats. Respectively, 58.8% (20/34) and 86.7% (26/30) resistant cell lines confirmed the transgenic integration by PCR. Moreover, pAPLM cells lines were subcultured with several passages, only 20% (6/30) cell lines was observed fluorescence from each cell during the cell passage. Somatic cell nuclear transfer using the donor cells harbouring pBLC14 or pAPLM construct, resulting in a total of 806 reconstructed embryos, a pregnancy rate at 35 d (53.8%, 39.1%) and 60 d (26.9%, 21.7%), and an offspring birth rate (1.9%, 1.4%) with 5 and 7 newborn cloned goats, respectively. Transgene was confirmed by PCR and southern-blot in all cloned offspring. There were no significant differences at the reconstructed embryo fusion rates, pregnancy rates and the birth rate (P > 0.05) between single and double markers groups. The Neo(r)/GFP double markers could improve the reliability for accurately and efficiently selecting the genetically modified donor cells. No adverse effect was observed on the efficiency of transgenic goat production by SCNT using somatic cells transfected with double (Neo(r)/GFP) markers vector.
Animals ; Animals, Genetically Modified ; genetics ; Cloning, Molecular ; Cloning, Organism ; methods ; veterinary ; Fetus ; Fibroblasts ; cytology ; Genetic Markers ; Goats ; embryology ; genetics ; Green Fluorescent Proteins ; genetics ; Humans ; Lactoferrin ; biosynthesis ; genetics ; Neomycin ; Nuclear Transfer Techniques ; veterinary ; Recombinant Proteins ; biosynthesis ; genetics ; Transfection ; veterinary

Estrogen has anti-colorectal cancer effects which are thought to be mediated by mismatch repair gene (MMR) activity. Estrogen receptor (ER) expression is associated with microRNA (miRNA) expression in ER-positive tumors. However, studies of direct link between estrogen (especially estradiol E2), miRNA expression, and MMR in colorectal cancer (CRC) have not been done. In this study, we first evaluated the effects of estradiol (E2) and its antagonist ICI182,780 on the expression of miRNAs (miR-31, miR-155 and miR-135b) using COLO205, SW480 and MCF-7 cell lines, followed by examining the association of tissue miRNA expression and serum E2 levels using samples collected from 18 colorectal cancer patients. E2 inhibited the expressions of miRNAs in COLO205 cells, which could be reversed by E2 antagonist ICI 182.780. The expression of miR-135b was inversely correlated with serum E2 level and ER-beta mRNA expression in CRC patients' cancer tissues. There were significant correlations between serum E2 level and expression of ER-beta, miR-135b, and MMR in colon cancer tissue. This study suggests that the effects of estrogen on MMR function may be related to regulating miRNA expression via ER-beta, which may be the basis for the anti-cancer effect in colorectal cells.
Adaptor Proteins, Signal Transducing/genetics/metabolism ; Adult ; Aged ; Cell Line, Tumor ; Colorectal Neoplasms/*genetics/metabolism ; DNA Mismatch Repair/*genetics ; Estradiol/analogs & derivatives/blood/*pharmacology ; Estrogen Antagonists/pharmacology ; Estrogen Receptor beta/genetics/*metabolism ; Female ; *Gene Expression Regulation, Neoplastic ; Humans ; Male ; MicroRNAs/genetics/*metabolism ; Middle Aged ; MutS Homolog 2 Protein/genetics/metabolism ; Nuclear Proteins/genetics/metabolism ; RNA, Messenger/biosynthesis

In addition to DNA repair pathways, cells utilize translesion DNA synthesis (TLS) to bypass DNA lesions during replication. During TLS, Y-family DNA polymerase (Polη, Polκ, Polı and Rev1) inserts specific nucleotide opposite preferred DNA lesions, and then Polζ consisting of two subunits, Rev3 and Rev7, carries out primer extension. Here, we report the complex structures of Rev3-Rev7-Rev1(CTD) and Rev3-Rev7-Rev1(CTD)-Polκ(RIR). These two structures demonstrate that Rev1(CTD) contains separate binding sites for Polκ and Rev7. Our BIAcore experiments provide additional support for the notion that the interaction between Rev3 and Rev7 increases the affinity of Rev7 and Rev1. We also verified through FRET experiment that Rev1, Rev3, Rev7 and Polκ form a stable quaternary complex in vivo, thereby suggesting an efficient switching mechanism where the "inserter" polymerase can be immediately replaced by an "extender" polymerase within the same quaternary complex.
Binding Sites ; Crystallography, X-Ray ; DNA Repair ; DNA-Binding Proteins ; chemistry ; genetics ; metabolism ; DNA-Directed DNA Polymerase ; chemistry ; genetics ; metabolism ; Fluorescence Resonance Energy Transfer ; Humans ; Mad2 Proteins ; Nuclear Proteins ; chemistry ; genetics ; metabolism ; Nucleotidyltransferases ; chemistry ; genetics ; metabolism ; Protein Binding ; Protein Structure, Quaternary ; Protein Structure, Tertiary ; Proteins ; chemistry ; genetics ; metabolism ; Recombinant Proteins ; biosynthesis ; chemistry ; genetics

OBJECTIVETo study the effect of pGCsi-H1-APRIL on the growth of human colorectal cancer cells in transplated tumor in nude mice and to improve the effect of APRIL on proliferation and apoptosis of colorectal cancer (CRC).

METHODSHuman CRC model was established in nude mice, and the nude mice were treated with APRIL siRNA twice per week for 2 weeks. APRIL mRNA expression was surveyed by PCR and APRIL protein expression was detected by immunohistochemistry. The expression of PCNA protein was detected by ELISA. The expression of bcl-2 and bcl-xl was assessed by immunohistochemical staining, and TUNEL staining was used to detect apoptosis.

RESULTSThe expression of APRIL mRNA in the APRIL siRNA group was (0.13 ± 0.05) × 10(-3), significantly lower than that in the vector group (0.95 ± 0.04) × 10(-3) and the PBS group (0.96 ± 0.05) × 10(-3). The expression of APRIL protein in the APRIL siRNA group was (87.5 ± 5.0)% lower than that in the vector and PBS groups (P < 0.05). APRIL siRNA significantly suppressed the growth of SW480 tumor: the IR (inhibitory rate) of APRIL siRNA group was (60.7 ± 1.5)% (P < 0.05). The expression of PCNA in APRIL siRNA group was (176.8 ± 18.1) ng/ml, was (56.5 ± 2.0)% lower than that of PBS group (328.4 ± 22.8) ng/ml. Furthermore, the expressions of anti-apoptosis proteins bcl-2 and bcl-xl of APRIL siRNA group were (82.6 ± 4.5)% and (79.2 ± 3.5)% lower than those of the PBS group. The apoptotic rate of the APRIL siRNA group was 40.1% ± 2.5%, significantly higher than that in the vector group (2.5 ± 0.1)% and PBS group (2.5 ± 0.2)% (P < 0.05).

CONCLUSIONAPRIL siRNA may significantly suppress the growth and promote apoptosis in transplanted tumor of human colorectal cancer in nude mice. APRIL may become a candidate gene of gene therapy of human colorectal cancer.

Animals ; Apoptosis ; Cell Line, Tumor ; Cell Proliferation ; Colorectal Neoplasms ; genetics ; metabolism ; pathology ; Female ; Humans ; Ligands ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Neoplasm Transplantation ; Proliferating Cell Nuclear Antigen ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; RNA, Messenger ; metabolism ; RNA, Small Interfering ; genetics ; Random Allocation ; Tumor Necrosis Factor Ligand Superfamily Member 13 ; biosynthesis ; genetics ; bcl-X Protein ; metabolism

OBJECTIVETo obtain monoclonal antibodies (mAbs) against Chlamydia trachomatis Tarp protein.

METHODSChlamydia trachomatis serovar D recombinant Tarp fusion protein was cloned and expressed. Balb/c mice were immunized with recombinant Tarp fusion protein, and the spleen cells of the immunized mice were fused with SP2/0 mouse myeloma cells. The hybridoma cell lines secreting mAbs against Tarp protein were screened by an indirect immunofluorescence assay and subcloned by limiting dilution culture. The specificities of these mAbs to Tarp were determined by ELISA, and their isotype and chlamydial species specificity identified by an indirect immunofluorescence assay.

RESULTSRecombinant GST-Tarp fusion protein with a relative molecular mass of about 136 000 was successfully cloned and expressed. Seven hybridoma cell lines stably secreting specific mAbs against Tarp protein were obtained. All the 7 mAbs reacted strongly with Tarp protein but not with other chlamydial proteins. Two mAbs were identified to belong to IgG2a isotype and the other 5 to IgG1 isotype. All the 7 mAbs reacted strongly with chlamydia serovar A, D, and L2, but not with MoPn, 6BC, or AR39.

CONCLUSIONThe highly specific mAbs against Tarp protein have been obtained to facilitate further study of the structure and function of Chlamydia Tarp protein.

Animals ; Antibodies, Monoclonal ; biosynthesis ; Antibody Specificity ; Bacterial Proteins ; immunology ; Cell Line, Tumor ; Chlamydia trachomatis ; immunology ; HeLa Cells ; Humans ; Mice ; Mice, Inbred BALB C ; Nuclear Proteins ; immunology ; Recombinant Fusion Proteins ; immunology

Formation and nuclear export of pre-ribosomes requires many nucleolar complexes, hNoc4L which contains a conserved Noc doman is a homolog of nucleolar complex associated 4 (S. cerevisiae), but its function is completely unclear. Here, we successfully got the recombinant lentiviral vector p113.7-EF1-hNoc4L-Flag by replacing the U6 promoter in p113.7 with EF1alpha promoter, and then inserted hNoc4L to down-stream of the EF1alpha prompter. We determined the transduction efficiency in different mammalian cell lines based on lentiviral packaging system. Subsequently, we analyzed the immunogenicity of the recombinant lentivirus and stable expression of hNoc4L in RAW264.7 cells. The results showed that the recombinant lentivirus characterized a high transduction efficiency, long-term expression and low immunogenicity. Therefore, we pave the way for further identification of the biological activity of hNoc4L protein during ribosome biogenesis in mammalian.
Animals ; Cell Line ; Genetic Vectors ; genetics ; Lentivirus ; genetics ; metabolism ; Mice ; Nuclear Proteins ; biosynthesis ; genetics ; Promoter Regions, Genetic ; Recombinant Proteins ; biosynthesis ; genetics ; Saccharomyces cerevisiae Proteins ; biosynthesis ; genetics

MHC class II expression is controlled mainly at transcriptional level by class II transactivator (CIITA), which is a non-DNA binding coactivator and serves as a master control factor for MHC class II genes expression. Here, we describe the function of a novel splice-isoform of CIITA, DC-expressed caspase inhibitory isoform of CIITA (or DC-CASPIC), and we show that the expression of DCCASPIC in DC is upregulated upon lipopolysaccharides (LPS) induction. DC-CASPIC localizes to mitochondria, and protein-protein interaction study demonstrates that DC-CASPIC interacts with caspases and inhibits its activity in DC. Consistently, DC-CASPIC suppresses caspases-induced degradation of nitric oxide synthase-2 (NOS2) and subsequently promotes the synthesis of nitric oxide (NO). NO is an essential regulatory molecule that modulates the capability of DC in stimulating T cell proliferation/activation in vitro; hence, overexpression of DC-CASPIC in DC enhances this stimulation. Collectively, our findings reveal that DC-CASPIC is a key molecule that regulates caspases activity and NO synthesis in DC.
Alternative Splicing ; Amino Acid Sequence ; Animals ; Base Sequence ; CARD Signaling Adaptor Proteins ; genetics ; metabolism ; Cell Line ; Dendritic Cells ; drug effects ; immunology ; metabolism ; Humans ; In Vitro Techniques ; Lipopolysaccharides ; pharmacology ; Lymphocyte Activation ; Mice ; Mice, Inbred C57BL ; Mitochondria ; metabolism ; Molecular Sequence Data ; Nitric Oxide ; biosynthesis ; Nitric Oxide Synthase Type II ; metabolism ; Nuclear Proteins ; genetics ; metabolism ; Protein Isoforms ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; T-Lymphocytes ; immunology ; metabolism ; Trans-Activators ; genetics ; metabolism ; Up-Regulation ; drug effects

OBJECTIVEConstruction of a small interfering RNA (siRNA) eukaryotic expression vector specific to mouse myocardin gene and study on the role of myocardin-siRNA on differentiation of mouse bone mesenchymal stem cells (MSCs) into smooth muscle-like cells induced by PDGF-BB in vitro.

METHODSMouse MSCs were isolated from bone marrow and cultured with 50 mg/L PDGF-BB and fetal bovine serum (20%). Specific myocardin-siRNA sequence was cloned into a plasmid pGenesil-1.0 vector, which contained U6 promoter. The recombinant plasmid and control plasmid were transfected into MSCs which had been cultured with PDGF-BB for 6 days beforehand. The expression of myocardin mRNA was detected by RT-PCR 48 hours after the transfection. Immunohistochemistry was used to detect the SM-MHC and to identify the smooth muscle-like cells.

RESULTSThe recombinant plasmids carrying myocardin-siRNA sequences were constructed successfully and the myocardin mRNA was reduced 42.86% by pGen-myo-shRNA in comparing with that of the controls (P<0.01); and the expression of SM-MHC protein was down-regulated (P<0.01).

CONCLUSIONSubset of mouse MSCs have the potential to differentiate into smooth muscle-like cells, a possible cell source responsible for atherosclerotic plaque formation, and myocardin expression may play an important role during this process.

Animals ; Bone Marrow Cells ; cytology ; metabolism ; Cell Differentiation ; Cells, Cultured ; Down-Regulation ; Gene Silencing ; Genetic Vectors ; Male ; Mesenchymal Stromal Cells ; cytology ; metabolism ; Mice ; Muscle, Smooth, Vascular ; cytology ; Myocytes, Smooth Muscle ; cytology ; metabolism ; Myosin Heavy Chains ; metabolism ; Nuclear Proteins ; biosynthesis ; genetics ; physiology ; Plaque, Atherosclerotic ; pathology ; Plasmids ; Platelet-Derived Growth Factor ; pharmacology ; Proto-Oncogene Proteins c-sis ; RNA, Messenger ; metabolism ; RNA, Small Interfering ; Trans-Activators ; biosynthesis ; genetics ; physiology ; Transfection

OBJECTIVETo study the effects of antisense Bmi-1 (B cell-specific moloney murine leukemia virus insertion site 1) RNA on the growth, cell cycle and apoptosis of lung cancer cell line A549.

METHODSRecombinant plasmids carrying antisense Bmi-1 RNA were transfected into A549 cells, which expressed a high level of endogenous Bmi-1. The mRNA level of A549 cell was analyzed by real time quantitative RT-PCR and the protein level was determined using Western blot. MTT growth curve and plate colony forming assay were used to measure the effect of antisense Bmi-1 RNA expression on the growth of A549. Flow cytometry was used to analyze cell cycle and apoptosis.

RESULTSAntisense Bmi-1 RNA reduced the Bmi-1 expression at the protein level, but did not alter the mRNA level in A549 cells. Compared with the control cells, A549 cells transfected with antisense Bmi-1 RNA showed a strong inhibition of the cell growth. The number of plate colony formation of the antisense Bmi-1 transfected cells (0.67 +/- 0.50) was less than those of the control (73.0 +/- 4.1) and cells transfected with empty vector (67.0 +/- 4.0, P < 0.01). Transfection of antisense Bmi-1 RNA arrested the A549 cells at G₀/G₁ phase of the cell cycle and did not increase the apoptosis.

CONCLUSIONAntisense Bmi-1 RNA expression inhibits A549 cells proliferation, likely through the interference of Bmi-1 leading to an arrest of the proliferating cells at the G₀/G₁ phase.

Apoptosis ; Cell Cycle ; Cell Line, Tumor ; Cell Proliferation ; Down-Regulation ; Gene Expression Regulation, Neoplastic ; Humans ; Lung Neoplasms ; genetics ; metabolism ; pathology ; Nuclear Proteins ; biosynthesis ; genetics ; Polycomb Repressive Complex 1 ; Proto-Oncogene Proteins ; biosynthesis ; genetics ; RNA, Antisense ; pharmacology ; RNA, Messenger ; metabolism ; Recombinant Proteins ; genetics ; metabolism ; Repressor Proteins ; biosynthesis ; genetics ; Transfection