A novel nine gene signature integrates stemness characteristics associated with prognosis in hepatocellular carcinoma

Cancer stem cells(CSCs)are heterogeneous with self-renewal and differentiation ability.The mRNA expression-based stemness index(mRNAsi)described the similarity between tumor cells and CSCs,which is positively associated with the poor prognosis of cancer patients.However,the key prognostic genes related to mRNAsi in hepatocellular carcinoma(HCC)remains unclear.A 9-gene signature related to mRNAsi and HCC prognosis including PSMG3,SNRPD1,DTYMK,PIGU,NME1,TXNL4A,IPO4,PES1,and REXO4 was obtained.High expression of this signature indicates poor prognosis of HCC.PIGU was an independent prognostic factor of HCC,which was significantly associated with progression of HCC.Among them,DTYMK and NME1 enriched in pyrimidine metabolism,SNRPD1 and TXNL4A enriched in spliceosome and PIGU enriched in glycosyl phosphatidylinositol(GPI)-anchor biosynthesis pathways.High levels of IPO4,NME1,PES1,PIGU and SNRPD1 were closely associated with metastasis of HCC,and low levels of IPO4,PIGU and REOX4 were significantly associated with sorafenib resistance of HCC.High expression of the 9-gene signature was negatively correlated with the stromal cell infiltration,and positively correlated with specific immune subtypes-related to angiogenesis,M1/M2 macrophage polarization,and M2 response.The 9-gene signature was negatively correlated with the stroma,and SNRPD1 and TXNL4 were positively correlated with immune infiltrate.NME1 was negatively correlated with tumor purity.Therefore,a 9-gene signature related to mRNAsi and poor prognosis in HCC were identified,which can be used as biomarkers for the diagnosis of HCC and functional mechanism exploration of CSCs in HCC.These genes such as IPO4 and PIGU might drive the transition of tumor cells into CSCs which possibly controls the balance between metastasis and drug resistance in HCC.The challenge on balance between metastasis and drug resistance for tumor therapy was firstly reported by the present study.

Cyclic biaxial tensile strain enhances osteogenic differentiation in rat bone marrow-derived mesenchymal stem cells via activating ERα-Wnt3a/β-catenin pathway

The present study was designed to investigate the role of estrogen receptorα(ERα)in biaxial tensile strain(BTS)regulated osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells(rBMSCs).rBMSCs were derived fromrats and overexpressed ERα.The rBMSCs were subjected to BTS at 1Hz with a strain of 2%for 4 h per day,3 days,with or without ERαinhibitor ICI 182,780(ICI).Then,bone mineralization was performed by Alizarin Red Staining.The markers of osteogenic differentiation and downstream Wnt3a/β-catenin signaling were detected by western blotting.Results showed that BTS enhanced the osteogenic differentiation of rBMSCs,increased protein expression levels of alkaline phosphatase(ALP),runt-related transcription factor 2(Runx2),collagen type I(Col I)and osteocalcin(OCN),and it increased the protein expression levels of estrogen receptor(ER)α(ERα),Wnt3a,andβ-catenin.BTS The activated Wnt3a/β-catenin signaling pathway induced by BTS was abolished by ICI 182,780(ICI).In addition,overexpressing ERαin rBMSCs promoted the osteogenic differentiation by BTS.Taken together,BTS induced osteogenic differentiation of rBMSCs via the ERαand downstream canonical Wnt3a/β-catenin pathway.

Single-cell RNA sequencing reveals classical monocytes are the major precursors of rat osteoclasts

To dissect which subset of bone marrow monocyte is the major precursor of osteoclast,3-month-old rat bone marrow was obtained for single-cell RNA sequencing.A total of 6091 cells were acquired for detailed analysis,with a median number of 1206 genes detected per cell and 17,959 genes detected in total.A total of 19 cell clusters were recognized,with the main lineages identified as B cells,Granulocytes,Monocytes,T cells,Erythrocytes and Macrophages.Monocytes were further divided into classical monocytes and non-classical monocytes.Compared with non-classical monocytes,classical monocytes highly expressed osteoclast differentiation related genes Mitf,Spi1,Fos and Csf1r.Additionally,biological processes of classical monocytes were related to osteoclast differentiation.qPCR revealed differentially expressed genes of classical monocytes played a role in osteoclast differentiation.In conclusion,classical monocytes were identified as the main precursors of osteoclasts in rats,and may contribute to osteoclast differentiation by regulating S100a4,S100a6,S100a10,Fn1,Vcan and Bcl2a1.The results of this study contribute to the understanding of the origin of osteoclasts and may provide potential biomarkers for early diagnosis of bone metabolic diseases,as well as molecular and cellular targets for clinical intervention in bone metabolic diseases.