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Biology subjects

Dou, P.

Publications and source records attributed to Dou, P..

4 recordsLinked to original sources

1,3- and 1,4-linked Polysaccharides Uptake in Intestinal Cells Relies on Clathrin/Dynamin 1/Rab5-dependent Endocytosis

Natural polysaccharides are considered to be a promising feedstock for manufacturing sustainable materials. However, polysaccharides are believed by most biologists that they could not be absorbed by intestinal mucosa to enter circulation system owing to their high hydrophilicity and large molecule size. Herein, {beta}-1,3-linked glucan (GFPBW1) and -1,4-linked glucan (WGE) is used as the model polysaccharide and the transport experiments show that different linked and charged polysaccharides can permeate Caco-2 cell monolayers. The in vivo experiments demonstrate that GFPBW1 and WGE are detectable in rodent plasma and liver after oral administration the isotope (99mTc, 3H) and fluorescein labeled polysaccharides. Further study show that polysaccharide uptake requires clathrin heavy chain (CLTC) and its associated factors Rab5 and dynamin1 in intestinal cells using gene-knockdown strategies and inhibitors. Strikingly, polysaccharide absorption is attenuated in both CLTC intestine deficient mice and Rab5, dynamin1 conventional-knockout mice. Importantly, membrane receptors bone morphogenetic protein receptor type IA (BMPRIA), Dectin-1 and epidermal growth factor receptor (EGFR) are also critical for specific structural polysaccharide internalization. These findings provide novel insight to understand polysaccharide absorption mechanism and lay foundation for oral polysaccharide- based new drugs development.

pharmacology and toxicology↗

BNIP3 upregulation characterizes cancer cell subpopulation with increased fitness and proliferation

BNIP3 is a BH3 only protein with both pro-apoptotic and pro-survival roles depending on the cellular context. It remains unclear how BNIP3 RNA level dictates cell fate decisions of cancer cells. Here we undertook a quantitative analysis of BNIP3 expression and functions in single cell datasets of various epithelial malignancies. Our results demonstrated that BNIP3 upregulation characterizes cancer cell subpopulations with increased fitness and proliferation. We further validated the upregulation of BNIP3 in liver cancer organoids compared with 2D culture. Taken together, the combination of in silico perturbations using public single cell datasets and experimental cancer modeling using organoids ushered in a new approach to address cancer heterogeneity.

systems biology↗

Discovery of novel ID2 antagonists from pharmacophore-based virtual screening as potential therapeutics for glioma

Glioma, especially the most aggressive type glioblastoma multiforme, is one of the central nervous system malignant cancer with a poor prognosis. Traditional treatments are mainly surgery combined with radiotherapy and chemotherapy, which is still not satisfactory. Therefore, it is of great clinical significance to find new therapeutic agents. Served as an inhibitor of differentiation, protein ID2 (inhibitor of DNA binding 2) plays an important role in neurogenesis, neovascularization and malignant development of gliomas. It has been shown that ID2 affects the malignant progression of gliomas through different mechanisms. In this study, a pharmacophore-based virtual screening was carried out and 16 hit compounds were purchased for pharmacological evaluations on their ID2 inhibitory activities. Based on the cytotoxicity of these small-molecule compounds, two compounds were shown to effectively inhibit the viability of glioma cells in the low micromolar range. Among them, AK-778-XXMU was chosen for further study due to its better solubility in water. A SPR assay proved the high affinity between AK-778-XXMU and ID2 protein with the KD value as 129 nM. The plausible binding mode in the biding site of ID2 was studied by molecular docking. Subsequently, the cancer-suppressing potency of the compound was characterized both in vitro and in vivo. The data demonstrated that compound AK-778-XXMU is a potent ID2 antagonist which has the potential to be developed as a therapeutic agent against glioma. HighlightsO_LITwo pharmacophores were built from the first-in-class pan-ID antagonists AGX51 C_LIO_LIA pharmacophore-based virtual screening was carried out and 16 hit compounds were purchased for pharmacological evaluations in glioma inhibition C_LIO_LICompound AK-778-XXMU was identified to be a potent ID2 antagonist in the low submicromolar range (KD: 159 nM) C_LI

cancer biology↗

The depletion of MARVELD1 leads to placenta accreta via integrin β4-dependent trophoblast cell invasion

AstractThe mammalian placenta is a remarkable organ. It serves as the interface between the mother and the fetus. Proper invasion of trophoblast cells into the maternal decidua is required for a successful pregnancy. Previous studies have found that the adhesion molecule integrin {beta}4 plays important roles during trophoblast cell invasion. Here, we found that the overall birth rate of the MARVELD1 knockout mouse is much lower than that of the wild-type mouse (P<0.001). In E18.5 MARVELD1 knockout mice, we observed an over-invasion of trophoblast cells, and indeed, the pregnant mice had a partial placenta accreta phenotype. The HTR8/SVneo cell line was used as an in vitro model to elucidate the underlying mechanisms of MARVELD1-mediated trophoblast invasion. We detected a diminished expression of integrin {beta}4 upon the downregulation of MARVELD1 and enhanced migration and invasive abilities of trophoblast cells both in vivo and in vitro. The integrin {beta}4 rescue assay also supported the results. In conclusion, this study found that MARVELD1 mediated the invasion of trophoblast cells via regulating the expression of integrin {beta}4.

developmental biology↗