1.Blocking autophagy magnifies MK-2206-induced DNA damage in SGC-7901 cells
Cui ZHANG ; Wenyan JIANG ; Yumei WU ; Mengwei ZHUANG ; Xishuang WANG ; Peng JIAO
Chinese Journal of Pathophysiology 2015;(9):1545-1549
AIM:To investigate the effect of MK-2206, an inhibitor of protein kinase B (Akt), on the DNA damage of SGC-7901 cells.METHODS: SGC-7901 cells were treated with different concentrations of MK-2206, and phosphorylated histone H2AX (γ-H2AX) foci formation was detected by immunofluorescence staining .Western blot analy-sis was used to exam the levels of DNA damage-related protein.The expression of LC3-Ⅱ was determined to evaluate the change of autophagy .RESULTS:MK-2206 treatment increased the formation of γ-H2AX foci and histone H2AX phospho-rylation in the SGC-7901 cells.The levels of DNA damage response protein were also increased .In addition, MK-2206-treated SGC-7901 cells increased the expression of LC 3-II, a hallmark of autophagy .Inhibition of autophagy significantly enhanced MK-2206-mediated histone H2AX phosphorylation.CONCLUSION:MK-2206 induces DNA damage and auto-phagy in SGC-7901 cells.Blocking autophagy potentiates the response of MK-2206-induced DNA damage .
2.Treatment and Outcome of Merkel Cell Carcinoma in A Single Center
Mengwei REN ; Xuemin XUE ; Peng LIU
Cancer Research on Prevention and Treatment 2023;50(4):364-369
Objective To investigate the clinical features, treatment, and outcome characteristics of patients with Merkel cell carcinoma. Methods The clinical manifestations, laboratory tests, diagnosis and treatment, and follow-up data of six patients with Merkel cell carcinoma were retrospectively analyzed. Results Among the six patients with Merkel cell carcinoma, four were males and two were females, with a median age of 66 years old (57-76 years old). All six patients presented with skin swelling, and the clinical stages were as follows: stageⅠ in three patients, stage Ⅲ in one patient, and stage IV in two patients. Two patients were treated with surgery alone, three patients with surgery combined with radiotherapy and/or chemotherapy, and one patient with immunotherapy combined with chemotherapy. Until the follow-up time, four patients had no disease progression, one patient died because of disease progression, and one patient remained under treatment. Conclusion Limited-stage Merkel cell carcinoma is primarily treated with surgery and radiotherapy, meanwhile, metastatic Merkel cell carcinoma needs systemic therapy, and first-line immune checkpoint inhibitors targeting PD-1/ PD-L1 pathway can achieve better therapeutic results.
3.Mechanism of Xiaoqinglong Decoction and Qingqi Huatan Pills in improving pathological airway mucus based on nuclear factor-κB/microRNA-494 signaling regulation of mucin 5AC and cystic fibrosis transmembrane conductance regulator
Mengwei PENG ; Yan LIU ; Yulong CHEN ; Yan ZHANG ; Yazhou SANG ; Linglun HAO ; Yaosong WU
Chinese Critical Care Medicine 2022;34(8):831-836
Objective:To observe the effects of Xiaoqinglong Decoction and Qingqi Huatan Pills on interleukin-1β(IL-1β)-induced mucushypersecretion model of human airway epithelial H292 cellsand related molecules of nuclear factor-κB/microRNA-494 (NF-κB/miR-494) signaling pathway, and to explore the mechanism of the two medicines in improving pathological airway mucus.Methods:Methyl thiazolyl tetrazolium (MTT) colorimetric method was used to detect the effects of different concentrations of Xiaoqinglong Decoction and Qingqi Huatan Pills on the activity of H292 cellsinduced by IL-1β, and the appropriate concentration was selected for subsequent experiments. Cells were randomly divided into blank group, IL-1β model group (5 μg/L IL-1β), NF-κB inhibitor pyrrolidinedithiocarbamate (PDTC) group (5 μg/L IL-1β+100 μmol/L PDTC), Xiaoqinglong Decoction (5 μg/L IL-1β+1 000 mg/L Xiaoqinglong Decoction) and Qingqi Huatan Pill group (5 μg/L IL-1β+1 000 mg/L Qingqi Huatan Pills). 5 μg/L IL-1β was used to induce H292 cells for 24 hours to establish a model of airway epithelial mucus hypersecretion. Enzyme linked immunosorbent assay (ELISA) method was used to detect the levels of mucin 5AC (MUC5AC), tumor necrosis factor-α (TNF-α) and IL-8 and the synthesis of intracellular MUC5AC and cystic fibrosis transmembrane conductance regulator (CFTR). Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression levels of MUC5AC mRNA, CFTR mRNA, miR-494. Western blotting was used to detect protein expression of key proteins (p65) and NF-κB inhibitors (IκB) in NF-κB signaling pathway.Results:Xiaoqinglong Decoction and Qingqi Huatan Pills with the concentration of 1 000 mg/L were selected for the follow-up experiment. Compared with the blank group, the levels of MUC5AC, TNF-α and IL-8 were significantly increased in the model group, intracellular MUC5AC protein content and mRNA expression were also significantly increased, intracellular CFTR protein content and mRNA expression were significantly decreased, and intracellular p65 protein expression was significantly up-regulated, the expression of IκB protein was significantly down-regulated, and the expression of miR-494 was significantly increased. Compared with the model group, the levels of MUC5AC, TNF-α and IL-8 were significantly reduced in PDTC group, Xiaoqinglong Decoction group and Qingqi Huatan Pill group, intracellular MUC5AC protein content and mRNA expression were also significantly decreased, and intracellular p65 protein expression was significantly down-regulated, and IκB protein expression was significantly up-regulated, miR-494 expression was significantly reduced. Intracellular CFTR protein content and mRNA expression were significantly increased in both PDTC group and Qingqi Huatan Pill group. Compared with the PDTC group, the level of TNF-α in the Xiaoqinglong Decoction group was significantly increased (ng/L: 22.77±3.14 vs. 11.09±3.37, P < 0.05), the content and mRNA expression of CFTR and IκB protein expression was significantly decreased [CFTR protein (ng/L): 97.38±6.62 vs. 227.04±19.48, CFTR mRNA (2 -ΔΔCt): 0.99±0.08 vs. 1.21±0.08, IκB/β-actin: 1.69±0.11 vs. 2.00±0.18, all P < 0.05], the level of TNF-α in Qingqi Huatan Pill group was significantly higher (ng/L: 19.08±3.71 vs. 11.09±3.37, P < 0.05). Compared with Xiaoqinglong Decoction group, the protein content and mRNA expression of CFTR and IκB protein expression in Qingqi Huatan Pill group were significantly increased [CFTR protein (ng/L) : 235.01±22.71 vs. 97.38±6.62, CFTR mRNA(2 -ΔΔCt): 1.32±0.15 vs. 0.99±0.08, IκB/β-actin: 1.94±0.16 vs. 1.69±0.11, all P < 0.05]. Conclusions:The effect of Xiaoqinglong Decoctionin improving the hypersecretion of mucus in the airway epithelium may be related to the inhibition of NF-κB/miR-494 inflammatory signal-mediated MUC5AC hypersecretion, while the effect of Qingqi Huatan Pills may be related to the inhibition of NF-κB/miR-494 inflammatory signal-mediated MUC5AC hypersecretion and CFTR dysfunction. Therefore, the difference in the mechanism of the two treatments of airway pathological mucus is mainly in the regulation of CFTR mRNA and protein.