OBJECTIVETo study the effects of losartan, an angiotensin II receptor blocker, in the SCC4 and SCC25 human tongue squamous cell carcinoma cell lines.METHODSCell proliferation was measured by MTS/PMS activity and trypan blue exclusion assays. The levels of the cell proliferation marker, cyclin D1, were analyzed by western blotting. Apoptosis was assessed by caspase-3 activation and Annexin V-FITC/propidium iodide double staining. Activation of epidermal growth factor receptor (EGFR) and ERK1/2 was validated by western blotting.RESULTSModerate concentrations of losartan enhanced the proliferation of SCC4 and SCC25 cells. However, high losartan concentrations induced apoptosis in SCC4 cells. Losartan activated the EGFR/ERK1/2/cyclin D1 signaling axis, which in turn promoted cell proliferation. Afatinib (EGFR inhibitor) and U0126 (ERK1/2 inhibitor) abolished losartan-induced cell proliferation. In contrast, UC2288 (p21 inhibitor) enhanced it.CONCLUSIONSLosartan exhibited dual effects on tongue squamous cell carcinoma cells. Moderate losartan concentrations facilitated cell proliferation, whereas high concentrations induced cytotoxicity in tongue carcinoma cells.

2024-08-01·Cell Death & Differentiation

DNMT1 regulates human erythropoiesis by modulating cell cycle and endoplasmic reticulum stress in a stage-specific manner

Article

作者: Zhang, Hengchao ; Chen, Lixiang ; An, Xiuli ; Zhao, Huizhi ; Sun, Lei ; Qu, Xiaoli ; Yang, Qianqian ; Wang, Ting ; Li, Mengjia ; Wu, Xiuyun

AbstractThe dynamic balance of DNA methylation and demethylation is required for erythropoiesis. Our previous transcriptomic analyses revealed that DNA methyltransferase 1 (DNMT1) is abundantly expressed in erythroid cells at all developmental stages. However, the role and molecular mechanisms of DNMT1 in human erythropoiesis remain unknown. Here we found that DNMT1 deficiency led to cell cycle arrest of erythroid progenitors which was partially rescued by treatment with a p21 inhibitor UC2288. Mechanically, this is due to decreased DNA methylation of p21 promoter, leading to upregulation of p21 expression. In contrast, DNMT1 deficiency led to increased apoptosis during terminal stage by inducing endoplasmic reticulum (ER) stress in a p21 independent manner. ER stress was attributed to the upregulation of RPL15 expression due to the decreased DNA methylation at RPL15 promoter. The upregulated RPL15 expression subsequently caused a significant upregulation of core ribosomal proteins (RPs) and thus ultimately activated all branches of unfolded protein response (UPR) leading to the excessive ER stress, suggesting a role of DNMT1 in maintaining protein homeostasis during terminal erythroid differentiation. Furthermore, the increased apoptosis was significantly rescued by the treatment of ER stress inhibitor TUDCA. Our findings demonstrate the stage-specific role of DNMT1 in regulating human erythropoiesis and provide new insights into regulation of human erythropoiesis.

2024-07-01·Phytomedicine

Ze-Qi-Tang formula inhibits MDSCs glycolysis through the down-regulation of p21/Hif1α/Glut1 signal in psoriatic-like mice

Article

作者: Zhu, Xiaowen ; Zou, Yimeng ; Liu, Mingxi ; Hou, Yifei ; Zou, Chunpu ; Zhu, Yangzhuangzhuang ; Jiang, Wencheng ; Su, Lin ; Yan, Xuewei ; Chen, Xiao ; Xu, Zihang ; Chen, Xi

BACKGROUNDPsoriasis is a chronic immune-mediated inflammatory skin disease that affects the quality of life and mental health of approximately 150 million people worldwide. Ze-Qi-Tang (ZQT) is a classic compound used in China for lung disease; however, its mechanism of action in psoriasis remains unclear. This study aimed to investigate the therapeutic effect of the ZQT formula on psoriasis and explore the underlying molecular mechanisms.METHODSPeripheral blood samples were collected from patients with psoriasis and healthy individuals. Flow cytometry was used to detect changes in the proportions of myeloid-derived suppressor cells (MDSCs) and other immune cells. Psoriasis was induced in mice by the daily application of imiquimod. ZQT was administered separately or in combination with anti-Gr1 antibody to deplete MDSC. The glycolysis levels of the MDSCs were detected using a Seahorse analyzer. The p21/Hif1α/Glut1 pathway was identified and validated by mRNA sequence, RT-qPCR, WB, IF, and the application of p21 inhibitor UC2288.RESULTSThe number of MDSCs was significantly increased in patients with psoriasis, with the increased expression of p21, Hif1α, and Glut1 in MDSCs. ZQT significantly alleviated psoriasis-like skin lesions in mice. ZQT formula significantly reduced the number of MDSCs in psoriatic-like mice and enhanced their suppressive capacity for T cells. The efficacy of ZQT in alleviating psoriatic dermatitis is compromised by MDSC depletion. ZQT decreased the expressions of p21, Hif1α, and Glut1-induced glycolysis in MDSCs, thereby inhibiting Th17 cell differentiation.CONCLUSIONThese suggest that ZQT alleviates IMQ-induced psoriatic dermatitis, by inhibiting p21/Hif1α/Glut1-induced glycolysis in MDSCs.

100 项与 UC2288 相关的药物交易

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