Growth differentiation factor 15 (GDF15), a direct target gene of p53, is a multifunctional member of the TGF-β/BMP superfamily. GDF15 can be induced and is implicated as a key secretory cytokine in response to multiple cellular stimuli. Accumulating evidence indicates that GDF15 is associated with the development and prognosis of diabetes mellitus, while whether GDF15 can be induced by high glucose is unknown. In the present study, we revealed that high glucose could induce GDF15 expression and secretion in cultured human umbilical vein endothelial cells in a ROS- and p53-dependent manner. Inhibition of high glucose-induced GDF15 expression by siRNA demonstrated that adaptively induced GDF15 played a protective role against high glucose-induced human umbilical vein endothelial cell apoptosis via maintaining the active state of PI3K/Akt/eNOS pathway and attenuating NF-κB/JNK pathway activation. The protective effects of GDF15 were probably achieved by inhibiting ROS overproduction in high glucose-treated human umbilical vein endothelial cells in a negative feedback manner. Our results suggest that high glucose can promote GDF15 expression and secretion in human umbilical vein endothelial cells, which in turn attenuates high glucose-induced endothelial cell apoptosis.

With the development of molecular cloning technology and the deep understanding of antibody engineering, there are diverse bispecific antibody formats from which to choose to pursue the optimal biological activity and clinical purpose. The single-chain-based bispecific antibodies usually bridge tumor cells with immune cells and form an immunological synapse because of their relatively small size. Bispecific antibodies in the IgG format include asymmetric bispecific antibodies and homodimerized bispecific antibodies, all of which have an extended blood half-life and their own crystalline fragment (Fc)-mediated functions. Besides retargeting effector cells to the site of cancer, new applications were established for bispecific antibodies. Bispecific antibodies that can simultaneously bind to cell surface antigens and payloads are a very ideal delivery system for therapeutic use. Bispecific antibodies that can inhibit two correlated signaling molecules at the same time can be developed to overcome inherent or acquired resistance and to be more efficient angiogenesis inhibitors. Bispecific antibodies can also be used to treat hemophilia A by mimicking the function of factor VIII. Bispecific antibodies also have broad application prospects in bone disorders and infections and diseases of the central nervous system. The latest developments of the formats and application of bispecific antibodies will be reviewed. Furthermore, the challenges and perspectives are summarized in this review.

Purpose: Transforming growth factor-β (TGF-β) is a potent immunosuppressor that has been associated with tumor evasion from the host immune surveillance and, thus, tumor progression. We tested a novel immunotherapy for human renal cell cancer (RCC) using a technique that involves the adoptive transfer of autologous tumor-reactive, TGF-β-insensitive CD8 + T cells into human RCC-challenged immunodeficient mice to identify its potent antitumor responses.Experimental Design: The present study was conducted using a one-to-one adoptive transfer strategy to treat tumor-bearing severe combined immunodeficient (SCID/beige) mouse. The SCID/beige mice were humanized with peripheral blood mononuclear cells from patients with RCC (Hu-PBMC-SCID) before adoptive transfer. Autologous CD8 + T cells were expanded ex vivo using autologous patient's dendritic cells pulsed with the tumor lysate and rendered TGF-β insensitive by dominant-negative TGF-β type II receptor. In addition, human RCC cell lines were generated using patients' tumor cells injected into SCID/beige mice. Renal cell carcinoma (RCC) is the most common solid tumor of the kidney in adults. It has previously been reported that the overproduction of TGF-β by RCC cells may lead to tumor evasion from the host immune surveillance and subsequent tumor progression (1-4). Similarly, inhibition of transforming growth factor-βTGF-β signaling using a dominant-negative TGF-β type II receptor construct (TβRIIDN) generates an immune response capable of eradicating tumors in mice challenged with live tumor cells (5).We have previously shown that murine CD8 + T cells that are rendered insensitive to TGF-β could activate the antitumor immune response cycle in prostate cancer and subsequently eradicate lung metastases (6, 7). Moreover, inhibition of TGF-β signaling in DC also enhanced the efficacy of 9). Although such TGF-β inhibition strategies are promising therapeutic approaches,

We investigated the role of a novel chimeric antigen receptor T-immunotherapy based on autologous metastatic castrate-resistant prostate cancer patient-derived prostate-specific membrane antigen (PSMA)-specific, transforming growth factor-ß insensitive CD8 T-cells on PSMA-positive prostate cancer. We found that this chimeric antigen receptor T-cells could kill PSMA-positive prostate cancer specifically. The results suggest that this novel immunotherapy treatment is a potential new approach for men with metastatic castrate-resistant prostate cancer.

RNA interference is highly effective at inhibiting HBV gene expression and replication. However, before small interfering RNA (siRNA) can be used in the clinic, it is essential to develop a system to target their delivery. Antibody-mediated delivery is a novel approach for targeting siRNA to appropriate cells. In this report, we asked whether this siRNA delivery strategy would be effective against HBV. Of 5 candidates, a specific siRNA that effectively inhibited HBV gene expression and replication was determined. Two fusion proteins, s-tP and sC-tP, were constructed to contain a single chain of the human variable fragment, scFv, against hepatitis B surface antigen (HBsAg), a truncated protamine (tP), and in the case of sC-tP, a constant region of the chain (C). S-tP and sC-tP were developed to provide targeted delivery of the siRNA, siRNA expressing cassettes (SEC), and siRNA-producing plasmids. Fluorescein isothiocyanate-siRNA, fluorescein isothiocyanate-SEC, and plasmid DNA were specifically delivered into HBsAg-positive cells using the sC-tP fusion protein, and effectively inhibited HBV gene expression and replication. HBV gene expression was also inhibited by siRNA or siRNA-producing plasmids in HBV transgenic mice. Conclusion: Our results describe a potential method for the targeted delivery of siRNA or siRNAproducing plasmids against HBV, using anti-HBsAg fusion proteins. (HEPATOLOGY 2007;46: 84-94.) R ibonucleic acid interference is a naturally occurring mechanism for silencing homologous genes. 1,2 Synthetic and plasmid-based siRNA expression systems are both effective at suppressing HBV infection, in vitro and in vivo, [3][4][5][6][7][8][9] providing the basis for a new therapeutic strategy against HBV. However, the absence of a suitable delivery system presents a major obstacle against their clinical use. [10][11][12] Targeted delivery of small interfering RNA (siRNA) to relevant cell populations should increase the therapeutic index and minimize potential side effects and cellular toxicity.Antibody-mediated delivery is an effective method of targeting siRNA to particular cells. This involves fusing the nucleic acid-binding domain to a Fab fragment or scFv that recognizes a membrane receptor, resulting in a fusion protein that possesses cell recognition and nucleic acid-binding abilities. The fusion protein can then bind nucleic acids and deliver them into target cells through receptor-mediated endocytosis. This antibody-mediated uptake has been successfully used to deliver plasmid DNA and antisense oligonucleotides. [13][14][15][16][17] Song et al. 18 demonstrated that siRNA targeted delivered to human immunodeficiency virus-infected cells and HER2 positive cells by this strategy executed gene silencing. However, whether this promising strategy for siRNA delivery is applicable to other diseases remains unknown. 19 In this report, we provide evidence that antibody-mediated siRNA delivery is effectively targeted to HBV-infected cells.In a previous study, we have obtained 5 human antihepatitis B sur...

Our aim was to clarify whether substitution of cytosine for adenine at position 1166 (A1166C) polymorphism of the angiotensin II type 1 receptor (AT1R) gene is associated with susceptibility to essential hypertension in Han, Tibetan and Yi populations in China. This study involved 302 normotensive and 446 hypertensive subjects. The polymorphism was detected by polymelase chain reaction of genomic DNA and restriction fragment length polymorphism (PCR-RFLP) in genomic DNA. The data were analyzed by analysis of covariance (ANCOVA), X2 test, and multiple logistic regression. In normotensive controls, the A1166 allele frequencies were 0.979, 0.939 and 0.965 in Han, Tibetan and Yi participants, respectively. There was no significant intergroup variation in frequency of the allele in normotensives (X2=4.166, p=0.125). The frequency of the A1166 allele was significantly higher in Tibetan male hypertensives than that in normotensives (X2=11.46, p=0.001). There was no significant difference in A1166C genotype distribution and allele frequency between normotensives and hypertensives either in the Han (p=0.465) or Yi (p=0.357) populations. Body mass index in the Han and Yi populations (p=0.0001), age in the Tibetan and Yi populations (p=0.0001), and AA genotype in the Tibetan male population (p=0.0034) all were independent risk factors for hypertension. Diastolic blood pressure levels were significantly higher in Tibetan male subjects with the AA genotype than in those with the AC+CC genotype (p=0.0040). We concluded that the A1166 allele is very common in Han, Tibetan and Yi populations, approximately 1.35-fold more common than in Caucasians. The A1166 allele of the AT1R gene may be a predisposing factor for essential hypertension in Tibetan males. A1166C polymorphism of the AT1R gene is probably not involved in the pathogenesis of essential hypertension in Han or Yi populations.

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Ghrelin regulates bone formation and osteoblast proliferation, but the detailed signaling pathway for its action on osteoblasts remains unclear. In human osteoblastic TE85 cells, we observed the effects and intracellular signaling pathway of ghrelin on cell proliferation using BrdU incorporation method. Ghrelin, at 10(-10)-10(-8) M concentration, significantly increased BrdU incorporation into TE85 cells. The action of ghrelin was inhibited by D: -Lys3-GHRP-6, a selective antagonist of GHS-R. Nitric oxide (NO) scavenger hemoglobin and the NO synthase inhibitor NAME eliminated the stimulatory action of ghrelin on proliferation, while NO donor SNAP and NO synthase substrate L-AME stimulated proliferation of osteoblastic TE85 cells. The cGMP analogue, 8-Br-cGMP, stimulated TE85 cell proliferation, and ghrelin did not enhance proliferation in the presence of 8-Br-cGMP. Inhibition of cGMP production by the guanylate cyclase inhibitor prevented ghrelin-induced osteoblastic TE85 cell proliferation. In conclusion, ghrelin stimulates proliferation of human osteoblastic TE85 cells via intracellular NO/cGMP signaling pathway.