Irradiated VEGF164-modified tumor cell vaccine protected mice from the parental tumor challenge.

Vascular endothelial growth factor (VEGF) is an important regulating molecule of angiogenesis in tumor formation and progression. Cancer cells always secrete VEGF to stimulate angiogenesis that facilitate growth and invasion of the tumor. In this study, we established a VEGF164 overexpressing LL/2 lung cancer cell model and found that the postirradiated VEGF164-modified tumor cells protected the host against the challenge with LL/2 wild-type tumor cells. Histochemical assay showed that there were large areas of tumor necrosis with macrophage infiltration in the mice vaccinated with the VEGF164-modified tumor vaccine. T-cells isolated from the vaccinated mice showed cytotoxicity against the parental tumor cells in a dose-dependent manner. Meanwhile, sera from the mice vaccinated with LL/2-VEGF164 showed higher titers of antibodies against parental tumor cells compared with the nonvaccinated groups. Our results indicated that VEGF164-modified tumor vaccine could modulate host antitumor immune response and hold therapeutic potential for cancer.

Vector-based miR-15a/16-1 plasmid inhibits colon cancer growth in vivo.

miR-15 (microRNA 15) and miR-16 are frequently deleted or down-regulated in many cancer cell lines and various tumour tissues, suggesting that miR-15a/16-1 plays important roles in tumour progression and might be a method for cancer treatment. We have developed a vector-based plasmid to explore the anti-tumour efficacy of miR-15a/16-1 in colon cancer in vivo. It is proposed that miR-15a and miR-16-1 target cyclin B1 (CCNB1), which associates with several tumorigenic features such as survival and proliferation. The levels of miR-15a and miR-16-1 in colon cancer cells were inversely correlated with CCNB1 expression, and there was consensus between miR-15a/16-1 and CCNB1 mRNA sequences by analysing homology. Vector-based miR-15a/16-1 expression plasmid was constructed and transfected into HCT 116 and SW620 colon cancer cells in vitro. The effects produced on cell viability and angiogenesis were analysed using flow cytometric analysis, colony formation analysis and tube formation analysis. CCNB1 expression down-regulation was checked by Western blotting. Systemic delivery of miR-15a/16-1 plasmids encapsulated in cationic liposome led to a significant inhibition of subcutaneous tumour growth and angiogenesis in tumour tissues, whereas no effects were observed with liposome carrying the non-specific plasmid. In summary, miR-15a/16-1 has been applied in colon cancer treatment in vivo, and resulted in effective colon tumour xenografts growth arrest and angiogenesis decrease. These findings suggest that systemic delivery of vector-based miR-15a/16-1 expression plasmid can be an approach to colon cancer therapy.

The p53 upregulated modulator of apoptosis (PUMA) chemosensitizes intrinsically resistant ovarian cancer cells to cisplatin by lowering the threshold set by Bcl-x(L) and Mcl-1.

Ovarian cancer is the number one cause of death from gynecologic malignancy. A defective p53 pathway is a hallmark of ovarian carcinoma. The p53 mutation correlates significantly with resistance to platinum-based chemotherapy, early relapse and shortened overall survival in ovarian cancer patients. PUMA (p53 upregulated modulator of apoptosis), a BH3-only Bcl-2 family protein, was recently identified as a transcriptional target of p53 and a potent apoptosis inducer in various cancer cells. In this study, we showed that the induction of PUMA by cisplatin was abolished in p53-deficient SKOV3 cells. Elevated expression of PUMA-induced apoptosis and sensitized A2780s and SKOV3 ovarian cancer cells to cisplatin, and the combination of PUMA and low-dose cisplatin, significantly suppressed xenograft tumor growth in vivo through enhanced induction of apoptosis compared with treatment with PUMA or cisplatin alone. The effects of PUMA were mediated by enhanced caspase activation and release of cytochrome c and Smac (second mitochondria-derived activator of caspase) into the cytosol. Furthermore, PUMA chemosensitized intrinsically resistant SKOV3 cells to cisplatin through downregulation of B-cell lymphoma-extra large (Bcl-x(L)) and myeloid cell leukemia sequence 1 (Mcl-1). PUMA-mediated Bcl-x(L) downregulation mainly happened at the transcription level, whereas PUMA-induced Mcl-1 down-regulation was associated with caspase-dependent cleavage and proteasome-mediated degradation. To our knowledge, these data suggest a new mechanism by which overexpression of PUMA enhances sensitivity of SKOV3 cells to cisplatin by lowering the threshold set simultaneously by Bcl-x(L) and Mcl-1. Taken together, our findings indicate that PUMA is an important modulator of therapeutic responses of ovarian cancer cells and is potentially useful as a chemosensitizer in ovarian cancer therapy.

The effect of miR-7 on behavior and global protein expression in glioma cell lines.

Malignant glioma is a common cancer of the nervous system. Despite recent research efforts in cancer therapy, the prognosis of patients with malignant glioma has remained dismal. MicroRNAs are noncoding RNAs that inhibit the expression of their targets in a sequence-specific manner, and a few have been shown to act as oncogenes or tumor suppressors. Here, we aimed at exploring the precise biological role of microRNA-7 (miR-7) and the global protein changes in glioma cell lines transiently transfected with miR-7. Transfection of miR-7 into glioma cell lines causes inhibition of cell migration and invasion and suppression of tumorigenesis. Moreover, ectopic expression of miR-7 inhibits lung metastases of glioma in vivo. Among 65 protein spots with differential expression separated by 2-DE, 37 proteins were successfully identified by MS/MS analysis. Of those, the 25 downregulated proteins, which include 14-3-3ζ, eukaryotic translation initiation factor 5A (EIF5A), and annexin A4, may be downstream targets of miR-7, a finding that could elucidate some aspects of the behavior of glioma cells at the protein level. In conclusion, the absence of miR-7 function could cause downstream molecules to switch on or off, resulting in glioma development, invasion, and metastases. MiR-7-based gene treatment may be a novel anti-invasion therapeutic strategy for malignant glioma.

RNA interference-mediated silencing of focal adhesion kinase inhibits growth of human malignant glioma xenograft in nude mice.

FAK (focal adhesion kinase), which plays a pivotal role in mediating cell proliferation, survival and migration, is frequently overexpressed in human malignant glioma. The expression of FAK increases with the advance of tumour grade and stage. Based on these observations, we hypothesized that attenuation of FAK expression may have inhibitory effects on the growth of malignant glioma. In the present study, human glioma cell line U251 was transfected with plasmids containing U6 promoter-driven shRNAs (small-hairpin RNAs) against human FAK using cationic liposome. The effects of FAK knockdown in U251 cells in vitro were analysed by using flow cytometry and PI (propidium iodide)-staining assays. Based on the encouraging in vitro results with FAK silencing, plasmids encoding FAK-targeted shRNA were encapsulated by DOTAP (dioleoyltrimethylammonium propane):Chol (cholesterol) cationic liposome and injected via tail vein to evaluate its therapeutic efficiency on suppressing tumour growth in a human glioma xenograft model. PCNA (proliferating-cell nuclear antigen), CD34 immunostaining and TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling) assay were used to assess the changes in tumour angiogenesis, apoptosis and proliferation respectively. The results indicated that DOTAP:Chol cationic liposome could deliver therapeutic plasmids systemically to tumour xenografts, resulting in suppression of tumour growth. Treatment with plasmid encoding FAK-targeted shRNA reduced mean tumour volume by approx. 70% compared with control groups (P<0.05), accompanied with angiogenesis inhibition (P<0.05), tumour cell proliferation suppression (P<0.05) and apoptosis induction (P<0.05). Taken together, our results demonstrated that shRNA-mediated silencing of FAK might be a potential therapeutic approach against human malignant glioma.

[RNA interference targeting focal adhesion kinase inhibited the growth of human hepatocellular carcinoma sk-hep-1].

OBJECTIVE: To test the impact of silencing focal adhesion kinase (FAK) gene on human hepatocellular carcinoma cell line sk-hep-1 using RNA interference (RNAi) in vitro, and its therapeutic effect on human hepatocellular carcinoma xenograft in vivo. METHODS: The plasmids generating short hairpin RNA that target FAK gene were transfected into sk-hep-1 cell line through Fugene HD. The impact was analyzed using flow cytometry, RT-PCR and western bolt. Human hepatocellular carcinoma xenograft in nude mice was established and treated with injection of the plasmids that packaged by cationic liposome into the tail veins the mice. The volumes and weights of the tumors were measured. The tumor tissues were analysed with FAK, CD31 and PCNA immunohistochemistry and TUNEL. RESULTS: The RNAi targeting FAK significantly down regulated the expression of FAK in mRNA and the level of protein (P < 0.001), and increased the cell apoptosis in vitro. The mice treated with pshFAK had slower tumor growth, resulting in smaller tumor size and lower tumor weight (P < 0.001) comparing to the controls. Decrease in FAK protein expression, tumor angiogenesis and proliferation, and increase in tumor apoptosis were found in the mice treated with pshFAK compared to the controls (P < 0.001). CONCLUSION: The shRNA targeting FAK suppresses the FAK expression of human hepatocellular carcinoma cells sk-hep-1, inhibits tumor growth, and promotes cell apoptosis in vitro and in vivo. FAK could become a candidate target for liver cancer treatment.

Bacterial Translocation Associates With Aggression in Schizophrenia Inpatients.

Objective: Accumulating evidence indicates that inflammation abnormalities may contribute to aggression behaviors in psychotic patients, however, the possible sources of inflammation remain elusive. We aimed to evaluate the associations among aggression, inflammation, and bacterial translocation (BT) in aggression-affected schizophrenia (ScZ) inpatients with 2 weeks of antipsychotics discontinuation. Methods: Serum specimens collected from 112 aggression and 112 non-aggression individuals with ScZ and 56 healthy adults were used for quantifications of inflammation- or BT-related biomarkers. Aggression severity was assessed by Modified Overt Aggression Scale (MOAS). Results: Proinflammation phenotype dominated and leaky gut-induced BT occurred only in cases with ScZ with a history of aggression, and the MOAS score positively related to levels of C-reactive protein, interleukin (IL)-6, IL-1ß, and tumor necrosis factor-α. Furthermore, serum levels of BT-derived lipopolysaccharide (LPS), as well as LPS-responded soluble CD14, were not only positively correlated with levels of above proinflammation mediators but also the total MOAS score and subscore for aggression against objects or others. Conclusion: Our results collectively demonstrate the presence of leaky gut and further correlate BT-derived LPS and soluble CD14 to onset or severity of aggression possibly by driving proinflammation response in inpatients with ScZ, which indicates that BT may be a novel anti-inflammation therapeutic target for aggression prophylaxis.

Antitumor and anti-angiogenesis immunity induced by CR-SEREX-identified Xenopus RHAMM.

Immunization with xenogeneic antigens is an attractive approach to induce cross-reactive humoral and cellular immunity to inhibit tumor growth or angiogenesis. To identify novel xenogenic targets for immunotherapy, we have developed a modified serological expression cloning (SEREX) strategy, termed Cross-reactive SEREX (CR-SEREX). Among 78 positive clones identified by CR-SEREX, Xenopus receptor for hyaluronic-acid-mediated motility (xRHAMM) was most frequently identified (18 times), indicating the strongest immunogenic potential for xenogenic immunotherapy. A DNA vaccine based on xRHAMM effectively induced a protective antitumor immunity against local tumor and lung metastasis in B16 melanoma mouse models. Angiogenesis was inhibited and cell apoptosis was increased within tumors. Antitumor activity of xRHAMM worked through stimulation of an antigen-specific cellular response as well as through a specific humoral response against RHAMM, as confirmed by the depletion of immune cell subsets in vivo. Thus, a xenogenic vaccine based on xRHAMM induced an effective immunity against B16 melanoma cells and endothelial cells.

Identification, characterization, and effects of Xenopus laevis PNAS-4 gene on embryonic development.

Apoptosis plays an important role in embryonic development. PNAS-4 has been demonstrated to induce apoptosis in several cancer cells. In this study, we cloned Xenopus laevis PNAS-4 (xPNAS-4), which is homologous to the human PNAS-4 gene. Bioinformatics analysis for PNAS-4 indicated that xPNAS-4 shared 87.6% identity with human PNAS-4 and 85.5% with mouse PNAS-4. The phylogenetic tree of PNAS-4 protein was also summarized. An analysis of cellular localization using an EGFP-fused protein demonstrated that xPNAS-4 was localized in the perinuclear region of the cytoplasm. RT-PCR analysis revealed that xPNAS-4, as a maternally expressed gene, was present in all stages of early embryo development. Whole-mount in situ hybridization showed that xPNAS-4 was mainly expressed in ectoderm and mesoderm. Furthermore, microinjection of xPNAS-4 mRNA in vivo caused developmental defects manifesting as a small eye phenotype in the Xenopous embryos, and as a small eye or one-eye phenotype in developing zebrafish embryos. In addition, embryos microinjected with xPNAS-4 antisense morpholino oligonucleotides (MOs) exhibited a failure of head development and shortened axis.

A novel transdermal plasmid-dimethylsulfoxide delivery technique for treatment of psoriasis.

BACKGROUND: Psoriasis is a chronic and relapsing inflammatory skin disease associated with various immunologic abnormalities. Repeated subcutaneous injection of interleukin-4 (IL-4) has been established as an effective treatment to counteract psoriasis. OBJECTIVE: We investigated whether gene therapy using IL-4 expression plasmid (pIL-4) via transdermal delivery was an alternative treatment for psoriasis. In our experiment, dimethylsulfoxide (DMSO) was used as a penetration enhancer. METHODS: At first, the penetration efficiency of the complex of reporter plasmid accompanied by DMSO was investigated both in vitro and in vivo. Then, the antipsoriasis efficiency of the treatment with pIL-4-DMSO was tested in mice. RESULTS: The expression of the reporter gene was detected in epidermis and dermis both in vitro and in vivo. More importantly, the psoriasis symptoms were relieved, and significant reductions in some psoriasis-associated factors were observed after pIL-4-DMSO treatment. CONCLUSION: We conclude that the topical application of pIL-4-DMSO can treat psoriasis to a significant extent.

RNA interference-mediated silencing of the phosphatidylinositol 3-kinase catalytic subunit attenuates growth of human ovarian cancer cells in vitroand in vivo.

OBJECTIVE: The phosphatidylinositol 3-kinase (PI3K) pathway plays a critical role in ovarian cancer cell survival and proliferation. The aim of this study was to determine whether the suppression of the PI3K catalytic subunit p110alphainhibits the growth of ovarian cancer cells in vitro and in vivo. METHODS: The short hairpin RNA (shRNA) was used to knock down the expression of p110alpha in SKOV3 human ovarian cancer cells. The effects of shRNA on cell viability and apoptosis in vitro were assessed using the MTT assay and flow-cytometric analysis. Furthermore, the growth inhibition capacity of shRNA on ovarian carcinoma xenografts was tested in nude mice. Tumor cell proliferation, apoptosis and angiogenesis were measured by proliferating cell nuclear antigen, TUNEL and CD31 immunohistochemistry, respectively. RESULTS: Using sequence-specific shRNA, we have silenced the expression of p110alpha in SKOV3 cells. shRNA-mediated knockdown of p110alpha correlated in vitro with decreased cell viability and increased apoptosis. Furthermore, inhibition of p110alpha significantly delayed the growth of ovarian carcinoma xenografts, and ultimately resulted in decreased cell proliferation, induction of apoptosis as well as a reduction in microvessel density. CONCLUSIONS: Our findings suggest that shRNA-directed targeting of p110alpharaises the potential of its application in human ovarian cancer therapy.

A promising cancer gene therapy agent based on the matrix protein of vesicular stomatitis virus.

The matrix (M) protein of vesicular stomatitis virus (VSV) plays a key role in inducing cell apoptosis during infection. To investigate whether M protein-mediated apoptosis could be used in cancer therapy, its cDNA was amplified and cloned into eukaryotic expression vector pcDNA3.1(+). The recombinant plasmid or the control empty plasmid pcDNA3.1(+) was mixed with cationic liposome and introduced into various tumor cell lines in vitro, including lung cancer cell LLC, A549, colon cancer cell CT26 and fibrosarcoma cell MethA. Our data showed that the M protein induced remarkable apoptosis of cancer cells in vitro compared with controls. Fifty micrograms of plasmid in a complex with 250 microg cationic liposome was injected intratumorally into mice bearing LLC or MethA tumor model every 3 days for 6 times. It was found that the tumors treated with M protein plasmid grew much more slowly, and the survival of the mice was significantly prolonged compared with the mice treated with the control plasmid. In MethA fibrosarcoma, the tumors treated with M protein plasmid were even completely regressed, and the mice acquired longtime protection against the same tumor cell in rechallenge experiments. Both apoptotic cells and CD8(+) T cells were widely distributed in M protein plasmid-treated tumor tissue. Activated cytotoxic T lymphocytes (CTLs) were further detected by means of (51)Cr release assay in the spleen of the treated mice. These results showed that M protein of VSV can act as both apoptosis inducer and immune response initiator, which may account for its extraordinary antitumor effect and warrant its further development in cancer gene therapy.

Immunotherapy of tumors with recombinant adenovirus encoding macrophage inflammatory protein 3beta induces tumor-specific immune response in immunocompetent tumor-bearing mice.

AIM: Tumor immunotherapy aims at activating the body's own immune system to fight an existing tumor. Effective antitumor responses require tumor antigens to be presented to lymphocytes. We aimed to test the hypothesis that intratumoral administration of recombinant adenovirus encoding MIP3beta would induce antitumor immunity by attracting and facilitating the interaction between lymphocytes and dendritic cells. METHODS: A recombinant adenovirus encoding microphage inflammatory protein 3beta (AdMIP3beta) was constructed. The antitumor activity of AdMIP3beta in BALB/c and C57BL/6 mice bearing CT26 colon adenocarcinoma and Lewis lung cancer was evaluated. RESULTS: Immunotherapy with AdMIP3beta resulted in significant inhibition of tumor growth and prolonged survival of tumor-bearing mice. Tumor-specific immune responses elicited by AdMIP3beta include MHC class I-dependent CD8(+) CTL-mediated immune response and IFN-gamma response. Immunohistochemical staining demonstrated numerous CD11c(+) cells and CD3(+) T lymphocytes within tumor tissues of AdMIP3beta-treated mice. These findings suggest that the mechanism of specific antitumor immunity induced by AdMIP3beta may be involved in the chemoattraction of both T lymphocytes and DCs to the tumor site and thus facilitate the process of antigen capture and mature DC to prime naive T cells. CONCLUSION: The present study may be important in the exploration of the potential application of AdMIP3beta in the treatment of a broad spectrum of tumors.

[Construction and identification of eukaryotic co-expression plasmid carrying FUS1 and recombinant human IL-12 genes and its effection on apoptosis of A549 cells].

OBJECTIVE: To construct a eukaryotic co-expression plasmid containing FUS1 and IL-12, and to investigate the influence of the recombinant plasmid on the cultured human lung cancer cell line A549. METHODS: RT-PCR was applied to amplify FUS1 from MRC-5 cell, the cDNA fragment of IL-12 was derived from pORF-hIL-12 by PCR, FUS1 cDNA fragment and IL-12 cDNA fragment were inserted into the multiple cloning sites of pVITRO2 to generate the eukaryotic co-expression plasmid pVITRO2-FUS1-IL-12. The recombinant plasmid was confirmed by restriction endonuclease treatment and sequenceing and transfected into A549 cells. The expression of genes in pVITRO2-FUS1-IL-12 were identified by RT-PCR, ELISA and Western blot. The function of pVITRO2-FUS1-IL-12 inducing the apoptosis of lung cancer was identified by Hoechst33258 and flow cytometry. RESULTS: The restriction endonuclease digestion and sequencing suggested that co-expression vector pVITRO2-FUS1-IL-12 was constructed successfully, the expression of FUS1 and IL-12 could be detected in A549 cells. The expressions of the two genes in pVITRO2 were not affected. The A549 cells transfected with pVITRO2-FUS1-IL-12 exhibited significant cell apoptosis. CONCLUSION: The recombinant eukaryotic expression vector pVITRO2-FUS1-IL-12 was constructed and expressed in eukaryotic cell successfully, which would contribute to a novel and effective treatment strategies for combined gene therapy for lung cancer.

Human alpha-defensin-1 inhibits growth of human lung adenocarcinoma xenograft in nude mice.

Human alpha-defensin-1 (HNP1), a small antimicrobial peptide, shows cytotoxicity to tumor cells in vitro and inhibitory activity for pathologic neovascularization in vivo. Here, we did a gene therapy with a plasmid that expresses a secretable form of HNP1 for assaying its antitumor activity. The expression and secretion of HNP1 were determined by reverse transcription-PCR and ELISA in vitro. We found that expression of HNP1 in A549 tumor cells caused significant growth inhibition. This effect is most likely cell autonomous, as a significant amount of recombinant HNP1 protein was found to be accumulated in the cytoplasm by immunohistochemical staining using an anti-HNP1 antibody and the supernatant containing secreted HNP1 failed to produce any noticeable antitumor activity. Flow cytometry and Hoechst 33258 staining showed that the number of apoptotic cells among the A549 cells expressing recombinant HNP1 proteins was significantly greater than that of the nontransfected control cultures, suggesting that this growth-inhibitory activity was due to an apoptotic mechanism triggered by the intracellular HNP1. The antitumor activity of intracellularly expressed HNP1 was also shown in vivo. Decreased microvessel density and increased lymphocyte infiltration were observed in tumor tissue from HNP1-treated mice through histologic analysis. These results indicate that intracellularly expressed HNP1 induces tumor cell apoptosis, which inhibits tumor growth. The antiangiogenesis effect of HNP1 may contribute to its inhibitory activity in vivo, and HNP1 might involve the host immune response to tumor. These findings provide a rationale for developing HNP1-based gene therapy for cancer.

[Enhanced expression of human vimentin intermediate filaments in hepatocellular carcinoma cells decreases their proliferative and invasive abilities in vitro].

OBJECTIVE: Expression of vimentin in carcinoma cells is a marker for poor prognosis in patients. The aim of this investigation was to assess the influence of vimentin on the characteristics of carcinoma cells. METHODS: The full-length vimentin gene open reading frame (1401 base pairs) was cloned into the plasmid vector pcDNA 3.1 (+), and these vectors were used to stably transfect the human hepatocellular carcinoma HepG2 cell line. Vimentin gene expression was evaluated by RT-PCR and Western blot. Proliferative activity and invasive potential of tumor cells were determined by the CellTiter 96 aqueous one solution cell proliferation assay and BioCoat GFR Matrigel invasion chamber, respectively. RESULTS: DNA sequencing and restriction endonuclease digestion analysis demonstrated that the recombinant vector was correctly cloned. The stable cell line demonstrated a higher vimentin RNA and protein expression. However, both proliferative and invasive abilities of the cells were reduced in vitro ( P < 0.05). CONCLUSION: A recombinant plasmid pcDNA3. 1-VIM is successfully constructed and a carcinoma cell line HepG2-pV highly expressing vimentin is obtained. Recombinant vimentin protein suppresses the proliferative and invasive abilities of HepG2 cells, suggesting that it might decrease malignant phenotype of tumor cells in vitro. This work makes a foundation for further study on the relationship between vimentin and biological phenotype of carcinoma cells.

[SEREX screening of human placenta antigens].

OBJECTIVE: To screen and obtain the potential human placenta antigens for the further application with serological analysis of recombinant cDNA expression library (SEREX). METHODS: SEREX technique with some modifications was applied. In brief, immune sera from rabbit immunized with human chorionic tissue were used to screen human placenta tissue cDNA expression library. Positive clone plaques were obtained after two rounds of screen. And the positive clone plaques were purified and sequenced. BLAST software was applied to comparison the obtained sequences with those found in GenBank for bioinformatic analysis. RESULTS: 69 positive clones were obtained from two rounds of screen. They were derived from 12 different genes, 9 of these were genes of known biology function, and 3 were genes of unknown biology function depending on the sequence analysis. Among the positive clones, chorionic somatomammotropin hormone 1 and 2 genes (CSH1 and CSH2) were found in 57 of positive clones (82.6%). This implied that the CSH1 and CSH2 might be the gene of encoding the important antigen and other genes obtained were related to the development of embryo. CONCLUSION: Modified xenogeneic immune SEREX technology is a very effective method to screen and isolate human placenta antigens. These antigens identified from this study might contribute to clarify the process of embryo development.

[Research on construction and expression of recombinant eukaryotic expression plasmid for mouse adiponectin].

OBJECTIVE: To construct the recombinant eukaryotic expression plasmid for mouse adiponectin so as to supply experimental basis for research further on the function of adiponectin. METHODS: Extracting the total RNA from mouse adipose tissue, applying RT-PCR to amplify the complete coding region of mouse adiponectin cDNA and connecting the amplified product with pCDNA3.1(+) vector; then verifying the recombinant plasmid by sequencing and detecting in vitro recombinant expression and cellular proliferation depression to mouse breast cancer cell 4T1. RESULTS: A 744 bp fragment was got after PCR amplification with the recombinant plasmid, which was confirmed by sequence and expression detected by Western-blot. Besides, compared with the control in vitro test, visible morphological changes of 4T1 cell could be observed after recombinant plasmid cell transfection for 48 h, with cells collapsed or shrunk and cellular proliferation inhibited. During the flow cytometry analysis, the transfected 4T1 cells could also be observed obviously to have a greater proportion of cell apoptosis than the control could be detected. CONCLUSION: The recombinant eukaryotic expression plasmid for mouse adiponectin is successfully constructed, which has an obvious inhibition effect on the proliferation of mouse breast cancer cell 4T1.

Identification and characterization of two novel variants of the DUF1208 protein FAM92A1.

FAM92A1 (named FAM92A1-271) belongs to the family of proteins with conserved DUF1208 domains. Its function remains elusive. We identified two novel transcript variants (FAM92A1-251, FAM92A1-289) of FAM92A1. The presence of these transcripts in cancerous and normal cells, as well as their influence on cell proliferation and apoptosis, were investigated. The subcellular location of FAM92A1 was determined by fluorescence microscopy. We found that FAM92A1-271 and FAM92A1- 289 were highly expressed in both normal and cancerous cells, but FAM92A1-251 was only expressed at a moderate level in both types of cell. Overexpression of FAM92A1-271, FAM92A1-251 and FAM92A1-289 inhibited cell proliferation, caused S-phase arrest and induced apoptosis. Subcellular localization showed that FAM92A1 localizes to the nucleus. Our results show that FAM92A1 has different splicing variants, and that it may take part in regulating cell proliferation and apoptosis.

Immunotherapy of tumors with protein vaccine based on chicken homologous Tie-2.

PURPOSE: Tie-2 is an endothelium-specific receptor tyrosine kinase known to play a key role in tumor angiogenesis. The present study explores the feasibility of immunotherapy of tumors by using a protein vaccine based on chicken Tie-2 as a model antigen to break the immune tolerance against Tie-2 in a cross-reaction between the xenogeneic homologous and self-Tie-2. EXPERIMENTAL DESIGN AND RESULTS: In this study, a chicken homologous Tie-2 protein vaccine (chTie-2) and a corresponding mouse Tie-2 vaccine as a control were prepared and the antitumor effect of these vaccines was tested in two tumor models (murine B16F10 melanoma and murine H22 hepatoma). Immunotherapy with chTie-2 was found effective in two tumor models. Autoantibodies against mouse Tie-2 were detected in sera of mice immunized with chTie-2 through Western blot analysis and ELISA assay. Anti-Tie-2 antibody-producing B cells were detectable by ELISPOT. Histologic examination revealed that autoantibodies were deposited on the endothelial cells of tumor tissues. Purified immunoglobulins from chTie-2-immunized mice could induce the apoptosis of human umbilical vein endothelial cells in vitro. Importantly, adoptive transfer of purified immunoglobulins led to antitumor effect in vivo; apparently, angiogenesis was significantly inhibited in these tumors. Furthermore, the antitumor activity and production of autoantibodies could be abrogated by depletion of CD4+ T lymphocytes. CONCLUSIONS: Our findings may provide a vaccine strategy for cancer therapy and show the potential utilization of interference with Tie-2 pathway.