Curcumin inhibits liver cancer by inhibiting DAMP molecule HSP70 and TLR4 signaling.

Curcumin has been revealed to inhibit liver cancer, however, no studies have reported that the mechanism of curcumin's action on liver cancer is related to damage-associated molecular pattern (DAMP) molecules heat shock protein 70 (HSP70) and the toll-like receptor 4 (TLR4) signaling. This study aimed to investigate whether the activation of TLR4 signaling by HSP70 could be inhibited by curcumin, thus investigating the possible mechanism of curcumin in the inhibition of liver cancer. Western blotting was used to evaluate the expression of the HSP70 and TLR4 in HepG2 cells and ELISA was used to detect the concentration of HSP70 in cell culture medium. A thermal tolerance HepG2 (HepG2TT) cell model was established to simulate HSP70 accumulation in the microenvironment. A certain concentration of curcumin was co-cultured with HepG2 and HepG2TT cells to observe the changes of HSP70 and TLR4. Our results revealed that heat stress significantly increased the expression of extracellular HSP70 (eHSP70) and TLR4 (P<0.01), but significantly reduced the expression of intracellular HSP70 (P<0.01). Curcumin inhibited proliferation, invasion, and metastasis of HepG2 cells, caused cells to remain in the DNA S phase, promoted apoptosis, and significantly reduced intracellular HSP70, eHSP70 and TLR4 levels of HepG2TT cells. Following the removal of curcumin, eHSP70 increased again. In summary, our results demonstrated that the antitumor effect of curcumin was related to the inhibition HSP70-TLR4 signaling.

Pseudomonas aeruginosa mannose-sensitive hemagglutinin inhibits proliferation and invasion via the PTEN/AKT pathway in HeLa cells.

We investigated the effects of Pseudomonas aeruginosa mannose-sensitive hemagglutinin (PA-MSHA) on the proliferation and invasion of human cervical cancer cell lines, as well as the molecular pathways underlying these effects. MTT cell proliferation assays revealed a time- and concentration-dependent cytotoxic effect of PA-MSHA on HeLa cells but not H8 cells. Flow cytometry with propidium iodide and annexin-V-fluorescein isothiocyanate labeling (FITC) indicated that various concentrations of PA-MSHA could induce apoptosis and G2-M cell cycle arrest in HeLa cells. PA-MSHA also impaired the migration and invasion abilities of HeLa cells in Wound healing and Transwell invasion assays. Western blot results demonstrated that PA-MSHA reduced the expression of p-AKT, p-GSK3ß, BCL-2, Vimentin and ß-catenin, but increased the levels of PTEN, BAD, BAX and E-cadherin in HeLa cells. Importantly, PTEN siRNA induced the activity of p-AKT, while PA-MSHA partly inhibited this induction, indicating that PA-MSHA may reduce the cell proliferation and invasion potential by activating PTEN and thus inhibiting the AKT pathway in vitro. These data suggest the potential application of PA-MSHA to the treatment of human cervical cancer.

Schistosoma japonicum scFv-IL18 fusion DNA ameliorates hepatic fibrosis in schistosomiasis-infected mice via improving local concentration of IL-18 in liver.

The pathogenesis of chronic schistosomiasis is caused by irritation of the schistosome eggs trapped in liver that induce delayed hypersensitive reactions from the surrounding tissues, leading to the formation of inflammatory granuloma and subsequent fibrosis. A Schistosoma japonicum (S. japonicum) single-chain fragment variable (SjscFv) which specifically binds to the S. japonicum soluble immature egg antigen (SIEA) can be used as a target to deliver specific cytokine towards the site of hepatic fibrosis. To test this hypothesis, a novel recombinant plasmid, pVAX1/SjscFv-IL18, was constructed by fusing SjscFv to IL-18 gene with a 45bp glycine-rich linker. Furthermore, experiments on mice showed that pVAX1/SjscFv-IL18 could effectively express IL-18 in the liver and in serum. Hepatic contents of IL-2 and IFN-γ (Th1-type) in S. japonicum-infected mice vaccinated with pVAX1/SjscFv-IL18 increased significantly but those of their IL-4 and IL-10 (Th2-type) decreased as compared to the analyzed results of 4 cytokines in the liver cells of control mice vccinated with pVAX1/IL18. Consistent with the levels of Th1 and Th2 cytokines, mice vaccinated with pVAX1/SjscFv-IL18 developed much less hepatic fibrosis 20weeks after infection, which was evaluated by average volumn of granuloma and collagen contents. These data suggested that the linkage of IL-18 to the target-specific SjscFv molecule appears to be a potentially promising trial route of therapy, the hepatic fibrosis in S. japonicum-infected mice may be ameliorated through effective expression of IL18 in liver.

A piezoelectric immunosensor using hybrid self-assembled monolayers for detection of Schistosoma japonicum.

BACKGROUND: The parasite Schistosoma japonicum causes schistosomiasis disease, which threatens human life and hampers economic and social development in some Asian countries. An important lesson learned from efforts to reduce the occurrence of schistosomiasis is that the diagnostic approach must be altered as further progress is made towards the control and ultimate elimination of the disease. METHODOLOGY/PRINCIPAL FINDINGS: Using mixed self-assembled monolayer membrane (mixed SAM) technology, a mixture of mercaptopropionic acid (MPA) and mercaptoethanol (ME) was self-assembled on the surface of quartz crystals by gold-sulphur-bonds. Soluble egg antigens (SEA) of S. japonicum were then cross-linked to the quartz crystal using a special coupling agent. As compared with the traditional single self-assembled monolayer immobilization method, S. japonicum antigen (SjAg) immobilization using mixed self-assembled monolayers exhibits much greater immunoreactivity. Under optimal experimental conditions, the detection range is 1:1500 to 1:60 (infected rabbit serum dilution ratios). We measured several infected rabbit serum samples with varying S. japonicum antibody (SjAb) concentrations using both immunosensor and ELISA techniques and then produced a correlation analysis. The correlation coefficients reached 0.973. CONCLUSIONS/SIGNIFICANCE: We have developed a new, simple, sensitive, and reusable piezoelectric immunosensor that directly detects SjAb in the serum. This method may represent an alternative to the current diagnostic methods for S. japonicum infection in the clinical laboratory or for analysis outside the laboratory.