Search

Six new compounds, including a tetralone 1, two xanthones 2 and 3, a flavan derivative 4, and two nor-diterpenoids 7 and 8, accompanied by two known flavan derivatives 5 and 6 and a known olefine acid (9) were isolated from whole bodies of Kronopolites svenhedini (Verhoeff). The structures of the new compounds were determined by 1D and 2D nuclear magnetic resonance (NMR) and other spectroscopic methods, as well as computational methods. Selected compounds were evaluated for their biological properties against a mouse pancreatic cancer cell line and inhibitory effects on iNOS and COX-2 in RAW264.7 cells.

As part of our continuous efforts to discover novel c-Met inhibitors as antitumor agents, four series of thiazole/thiadiazole carboxamide-derived analogues were designed, synthesised, and evaluated for the in vitro activity against c-Met and four human cancer cell lines. After five cycles of optimisation on structure–activity relationship, compound 51am was found to be the most promising inhibitor in both biochemical and cellular assays. Moreover, 51am exhibited potency against several c-Met mutants. Mechanistically, 51am not only induced cell cycle arrest and apoptosis in MKN-45 cells but also inhibited c-Met phosphorylation in the cell and cell-free systems. It also exhibited a good pharmacokinetic profile in BALB/c mice. Furthermore, the binding mode of 51am with both c-Met and VEGFR-2 provided novel insights for the discovery of selective c-Met inhibitors. Taken together, these results indicate that 51am could be an antitumor candidate meriting further development.

BackgroundCXCR5+CD8+ T cells have been demonstrated to play an important role in the control of chronic viral replication; however, the relationship between CXCR5+CD8+ T cells, HIV disease progression, and programmed cell death 1 (PD-1) expression profile on CXCR5+CD8+ T cells during HIV infection remain poorly understood.MethodsWe enrolled a total of 101 HIV patients, including 62 typical progressors, 26 complete responders (CRs), and 13 immune non-responders (INRs). Flow cytometric analysis, immunohistochemical staining, and relative function (i.e., cytokine secretion and PD-1 blockade) assays were performed to analyze the properties of CXCR5+CD8+ T cells.ResultsHIV-specific CXCR5+CD8+ T cells in the peripheral blood and distribution of CXCR5+CD8+ T cells in the lymph node (LN) were negatively correlated with disease progression during chronic HIV infection. PD-1 was highly expressed on CXCR5+CD8+ T cells and positively associated with peripheral CD4+ T cell counts. Functionally, IFN-γ and TNF-α production of CXCR5+CD8+ T cells were reduced by PD-1 pathway blockade, but the production of IFN-γ and TNF-α from CXCR5−CD8+ T cells increased in response to TCR stimulation. Interestingly, PD-1 expression was constantly retained on CXCR5+CD8+ T cells while significantly decreased on CXCR5−CD8+ T cells after successful antiretroviral treatment in chronic HIV-infected patients.ConclusionPD-1+CXCR5+CD8+ T cells are functional cytotoxic T cells during chronic HIV infection. PD-1+CXCR5+CD8+ T cells may represent a novel therapeutic strategy for the disease.