Spatial transcriptomics reveals that metabolic characteristics define the tumor immunosuppression microenvironment via iCAF transformation in oral squamous cell carcinoma / 国际口腔科学杂志·英文版

Tumor progression is closely related to tumor tissue metabolism and reshaping of the microenvironment. Oral squamous cell carcinoma (OSCC), a representative hypoxic tumor, has a heterogeneous internal metabolic environment. To clarify the relationship between different metabolic regions and the tumor immune microenvironment (TME) in OSCC, Single cell (SC) and spatial transcriptomics (ST) sequencing of OSCC tissues were performed. The proportion of TME in the ST data was obtained through SPOTlight deconvolution using SC and GSE103322 data. The metabolic activity of each spot was calculated using scMetabolism, and k-means clustering was used to classify all spots into hyper-, normal-, or hypometabolic regions. CD4T cell infiltration and TGF-β expression is higher in the hypermetabolic regions than in the others. Through CellPhoneDB and NicheNet cell-cell communication analysis, it was found that in the hypermetabolic region, fibroblasts can utilize the lactate produced by glycolysis of epithelial cells to transform into inflammatory cancer-associated fibroblasts (iCAFs), and the increased expression of HIF1A in iCAFs promotes the transcriptional expression of CXCL12. The secretion of CXCL12 recruits regulatory T cells (Tregs), leading to Treg infiltration and increased TGF-β secretion in the microenvironment and promotes the formation of a tumor immunosuppressive microenvironment. This study delineates the coordinate work axis of epithelial cells-iCAFs-Tregs in OSCC using SC, ST and TCGA bulk data, and highlights potential targets for therapy.

Advances in biodegradation of polyolefin plastics / 生物工程学报

Polyolefin plastics are a group of polymers with C-C backbone that have been widely used in various areas of daily life. Due to their stable chemical properties and poor biodegradability, polyolefin plastic waste continues to accumulate worldwide, causing serious environmental pollution and ecological crises. In recent years, biological degradation of polyolefin plastics has attracted considerable attention. The abundant microbial resources in the nature offer the possibility of biodegradation of polyolefin plastic waste, and microorganisms capable of degrading polyolefin have been reported. This review summarizes the research progress on the biodegradation microbial resources and the biodegradation mechanisms of polyolefin plastics, presents the current challenges in the biodegradation of polyolefin plastics, and provides an outlook on future research directions.

Lin28 overexpression promotes proliferation and inhibits osteogenic differentiation of human dental pulp stem cells in part through the mTOR signaling pathway / 安徽医科大学学报

Objective @#To investigate the effects of Lin28 overexpression on the proliferation and osteogenic differentiation of human dental pulp stem cells (hDPSCs) through mTOR signaling pathway.@*Methods @#After transfecting lentiviral vectors of Lin28 gene in hDPSCs , the relative expression of Lin28 was detected by Real⁃time PCR. CCK⁃8 assay was applied to detect the effect on cell proliferation. qRT⁃PCR was used to research the expression levels of alkaline phosphatase (ALP) , osteopontin (OPN) and osteocalcin (OCN) . Western blot assay was processed to investigate the effects on the relative expression levels of ALP and OPN proteins. Alizarin red staining was utilized to detect the mineralized nodules. @*Results @#Compared with the control group , the cell proliferation of transfection group was promoted (P < 0. 05) ; The mRNA and protein expression levels of ALP , OPN and OCN in transfection group were significantly lower than those in control group (P < 0. 05) , the expression level of ALP apparently decreased after the addition of mTOR inhibitor rapamycin (P < 0. 05) ; Alizarin red staining showed that the size and number of mineralized nodules formed in transfection group were markedly declined compared with empty carrier group (P < 0. 05) .@*Conclusion @#Overexpression of Lin28 can inhibit the osteogenic differentiation of hDP⁃ SCs through suppress mTOR signaling pathway.