Emerging roles of hsa_circ_0005075 targeting miR-431 in the progress of HCC.

Circular RNAs (circRNAs) are non-coding RNAs that play key roles in the pathogenesis of diseases and are associated with human hepatocellular carcinoma (HCC). Previous reports have shown the circRNA hsa_circ_0005075 is highly expressed in HCC tissues, but its function is unknown. In this study, we confirmed circ_0005075 is significantly increased in HCC tissues and cell lines. This overexpression was associated with increased numbers of proliferative, migrated and invasive SMMC-7721 cells. In addition, hsa_circ_0005075 inhibited the transcription activity of miR-431 measured by dual-luciferase reporter assays. In contrast, silencing hsa_circ_0005075 decreased cell number. Finally, effects after hsa_circ_0005075 silencing were rescued by co-transfection with miR-431 inhibitor. These results suggest hsa_circ_0005075 promotes HCC via miR-431 regulation.

Cryptolepine derivative-6h inhibits liver fibrosis in TGF-ß1-induced HSC-T6 cells by targeting the Shh pathway.

Liver fibrosis is a worldwide problem with a significant morbidity and mortality. Cryptolepis sanguinolenta (family Periplocaceae) is widely used in West African countries for the treatment of malaria, as well as for some other diseases. However, the role of C. sanguinolenta in hepatic fibrosis is still unknown. It has been reported that Methyl-CpG binding protein 2 (MeCP2) had a high expression in liver fibrosis and played a central role in its pathobiology. Interestingly, we found that a cryptolepine derivative (HZ-6h) could inhibit liver fibrosis by reducing MeCP2 expression, as evidenced by the dramatic downregulation of α-smooth muscle actin (α-SMA) and type I collagen alpha-1 (Col1α1) in protein levels in vitro. Meanwhile, we also found that HZ-6h could reduce the cell viability and promote apoptosis of hepatic stellate cells (HSCs) treated with transforming growth factor beta 1(TGF-ß1). Then, we investigated the potential molecular mechanisms and found that HZ-6h blocked Shh signaling in HSC-T6 cells, resulting in the decreased protein expression of Patched-1 (PTCH-1), Sonic hedgehog (Shh), and glioma-associated oncogene homolog 1 (GLI1). In short, these results indicate that HZ-6h inhibits liver fibrosis by downregulating MeCP2 through the Shh pathway in TGF-ß1-induced HSC-T6 cells.

NLRC5 promotes cell proliferation via regulating the AKT/VEGF-A signaling pathway in hepatocellular carcinoma.

NLRC5, a newly found member of the NLR family and the largest member of nucleotide-binding, has been reported to regulate immune responses and is associated with hepatocellular carcinoma (HCC). We investigated the mechanisms and signaling pathways of NLRC5 in HCC progression. Increased expression of NLRC5, vascular endothelial growth factor-A (VEGF-A) were found in human HCC tissue. There was a positive correlation between NLRC5 and VEGF-A expression and cell proliferation were enhanced in NLRC5-overexpressing HepG2 cells, but inhibited in cells with NLRC5 silencing treatment. Interestingly, we found that up-regulation of NLRC5 also coordinated the activation of PI3K/AKT signaling pathway. An AKT inhibitor LY294002 blocked VEGF-A expression and AKT phosphorylation in HepG2 cells and NLRC5-overexpressing HepG2 cells. These results demonstrate that NLRC5 promotes HCC progression via the AKT/VEGF-A signaling pathway.

Reversal of endothelial progenitor cell dysfunction in patients with type 2 diabetes using a conditioned medium of human embryonic stem cell-derived endothelial cells.

BACKGROUND: The potential clinical application of bone marrow or peripheral blood-derived progenitor cells for cardiovascular regeneration in patients with diabetes mellitus (DM) is limited by their functional impairment. We sought to determine the mechanisms of impaired therapeutic efficacy of peripheral blood-derived progenitor cells in type 2 DM patients and evaluated the use of cell-free conditioned medium obtained from human embryonic stem cell-derived endothelial-like cells (ESC-ECs) to reverse their functional impairment. METHODS: The angiogenic potential of late outgrowth endothelial cells (OECs) and cytokine profile of the conditional medium of proangiogenic cells (PACs) derived from peripheral blood-mononuclear cells of healthy control and DM patients and ESC-ECs was compared by in vitro tube formation assay and a multiplex bead-based immunoassay kit, respectively. The in vivo angiogenic potential of ESC-ECs derived conditioned medium in rescuing the functional impairment of PB-PACs in DM patients was investigated using a hindlimb ischemia model. RESULTS: Human ESC-ECs had similar functional and phenotypic characteristics as OECs in healthy controls. Cytokine profiling showed that vascular endothelial growth factor, stromal cell-derived factor 1 and placental growth factor were down-regulated in PACs from DM patients. Tube formation assay that revealed functional impairment of OECs from DM patients could be rescued by ESC-ECs conditioned medium. Administration of ESC-ECs conditioned medium restored the therapeutic efficacy of PB-PACs from DM patients in a mouse model of hindlimb ischemia. CONCLUSIONS: Our results showed that peripheral blood-derived progenitor cells from DM patients have impaired function because of defective secretion of angiogenic cytokines, which could be restored by supplementation of ESC-ECs conditioned medium.

Molecular mechanism of interaction and electron transfer between dihydric phenols and L-cysteine.

The mechanism and electron transfer for pollutant dihydric phenol and biomolecule L-Cysteine (L-Cys) interaction in aqueous solution were studied by means of electrochemistry and UV-VIS spectrophotometry. Two forms of L-Cys, fixed on Au-electrode and free dissolved in the solution, were examined. The results showed that L-Cys of an ordered monolayer fixed on an Au electrode facilitated electron transfer and electrocatalytic redox of three isomers of dihydric phenol. However, free L-Cys does not show such facility. Furthermore, neither cleavage of the original chemical bond nor formation of a new chemical bond was observed in the molecules investigated, suggesting that L-Cys molecules may associate tightly with dihydric phenol molecules to form L-Cys . C(6)H(6)O(2)or (L-Cys) (2) . C(6)H(6)O(2) complex molecule via hydrogen-bonding. Different coordination numbers influence the electrochemical activity and behavior of associated complexes; thus, the function of biomolecules could be affected.

[Cytotoxicity of cytotoxic T lymphocytes induced by keratin 19-sensitized dendritic cells against MCF-7 cells in vitro].

OBJECTIVE: To investigate the cytotoxicity of cytotoxic T lymphcytes (CTL) induced by keratin 19 (K19)-sensitized dendritic cells (DC) against MCF-7 cells in vitro. METHODS: DC isolated from peripheral blood mononuclear cells were cultured in vitro and sensitized by K19 peptide to generate specific CTL. The phenotypes and intracytoplasm cytokine of DC were analyzed by flow cytometry. Mixed leukocyte responses were evaluated by (3)H-TdR incorporation assay. The T cells were generated by DC pulsed with K19 antigen and T cell cytotoxicity was measured by (51)Cr release assay. RESULTS: The DCs derived from peripheral blood mononuclear cells expressed high levels of CD40, CD86, CD80 and CD83. Mixed leukocyte responses induced by the DCs pulsed with K19 was stronger than that induced by naive DCs (P<0.01). The cytotoxicity rate of CTL induced by the sensitized DCs was higher than that of CTL induced by naive DCs (P<0.01). The cytotoxity activity was enhanced by increasing the effector/target ratio (P<0.01). CONCLUSION: After sensitization with K19 antigen, the DCs can stimulate T cell proliferation and induce cytotoxicity activity against MCF-7 cells. Increased effector/target ratio may enhance the cytotoxity activity. Sensitized DCs possess the potential for amplification in immunotherapy of carcinoma.