1.Effects of stanniocalcin l on cell cycle and apoptosis of lung cancer A549 cells
Niya LI ; Xuemei ZUO ; Li LI ; Hua LIU ; Yuzhen DU
China Oncology 2016;26(8):641-647
Background and purpose:Stanniocalcin 1 (STC1) has been reported to be up-regulated in various cancer tissues, and related to malignancy degree of cancer. However, the molecular mechanism of STC1 in lung cancer cells is still not clear. This experiment aimed to investigate the effects of STC1 on cell cycle and apoptosis of lung cancer A549 cells.Methods:A549 cells were transfected with validated siRNA for STC1 A549-STC1-siRNA and a negative control vector RNA A549-Vector. The gene and protein expression of cell cycle-related genes, including CyclinA, CyclinB1, CyclinD1, CyclinE, CDK2 and CDK4, as well as apoptosis-inhibiting genes Bcl-2, Bcl-xl and apoptosis-inducing genes Caspase-3, Bax, Bak and Bid, were detected by real-time lfuorescent quantitative polymerase chain reaction (RTFQ-PCR) and Western blot. The cell cycle distribution was determined with lfow cytometry. Terminal deoxynucleotidyl transferase-mediated nick-end labeling (TUNEL) was used to detect cell apoptosis.Results:After transfection with STC1-siRNA, the gene and protein expression of CyclinA, CyclinB1, CyclinD1, CyclinE, CDK2 and CDK4 decreased signiifcantly in A549 cells (P<0.05). The proportion of cells in G0/G1 phase signiifcantly increased,
whereas the proportion of cells in S phase and G2/M phase decreased (P<0.05). The cell cycle was blocked at G0/G1 phase. Furthermore, compared with that in A549-Vector, the gene and protein expression of Bcl-2 and Bcl-xl in A549-STC1-siRNA was reduced signiifcantly (P<0.05), while the expression of apoptosis-inducing genes Caspase-3, Bax, Bak and Bid increased obviously (P<0.05). In addition, the percentage of apoptotic cells significantly increased in A549-STC1-siRNA compared with that in A549-Vector detected by TUNEL method.Conclusion:Down-regulation of STC1 by RNAi can block the cell cycle of A549 cells, inhibit cell proliferation, and promote cell apoptosis.
2.Adipose stem cell-derived growth factors and proliferation of oral mucosa fibroblasts
Jiajia ZHAO ; Li HU ; Jiarong LIU ; Niya GONG ; Lili CHEN
Chinese Journal of Tissue Engineering Research 2013;(32):5778-5784
Adipose stem cel s have been confirmed to promote the repair of soft tissue after damage, and the action mechanism is possibly related to the paracrine of adipose stem cel s, that is adipose stem cel s secrete a variety of cytokines, which may promote the restoration of damaged cel s. However, little report addressed the types of adipose stem cel s secreted factors, contents of each factor, and role in soft tissue repair after damage, especial y oral mucosa. To observe the influence of vascular endothelial growth factor, platelet-derived growth factor, and basic fibroblast growth factor in adipose stem cel-conditioned medium on the proliferation of oral mucosa fibroblasts. Protein microarray analysis was used to analyze the contents of vascular endothelial growth factor, platelet-derived growth factor, and basic fibroblast growth factor in adipose stem cel-conditioned medium. CCK8 analysis was used to analyze the effects of adipose stem cel-conditioned medium with different concentrations of vascular endothelial growth factor, platelet-derived growth factor, and basic fibroblast growth factor (0, 1, 10, 20, 50 and 100μg/L) or the neutralizing antibody of the three kinds of cytokines on the proliferation of oral mucosa fibroblast on 1, 2, 3, 4 and 5 days. High contents of vascular endothelial growth factor, platelet-derived growth factor, and basic fibroblast growth factor were contained in adipose stem cel-conditioned medium (signal value>300). Adipose stem cel-conditioned medium could promote the proliferation of oral mucosa fibroblasts, wherein, the promotion effects of platelet-derived growth factor and basic fibroblast growth factor were very significant, and the peak changes could be observed with variation of cytokines concentrations. The optimal concentrations of platelet-derived growth factor and basic fibroblast growth factor were 50μg/L and 1μg/L, respectively (P ≤ 0.05). The neutralizing antibody of platelet-derived growth factor and basic fibroblast growth factor inhibited the promotion effect of adipose stem cel-conditioned medium. On the other hand, vascular endothelial growth factor had no significant effect on the proliferation of oral mucosa fibroblasts. Adipose stem cel-conditioned medium can promote the proliferation of oral mucosa fibroblasts, platelet-derived growth factor and basic fibroblast growth factor in adipose stem cel-conditioned medium have obvious promotion effects, which are dependent on the cytokine concentrations. Therefore, we should pay attention to choose the optimal concentrations of cytokines, thereby effectively promoting the proliferation of fibroblasts.
3.Influence of blocking gastrin receptor on the proliferation and apoptosis and expression of keyproteins in related pathway of gastric cancer cell
Hang YUAN ; Chuang WANG ; Qinrong WANG ; Yan ZHAO ; Yajie LI ; Niya LONG ; Jianjiang ZHOU
Chongqing Medicine 2017;46(15):2017-2020
Objective To investigate the effects of blocking gastrin receptor on the proliferation,apoptosis and expression of key proteins in the related pathway in gastric cancer cell lines.Methods In the experimental group,the gastric cancer cell lines SGC-7901 and AGS cells were treated with 5 mmol/L proglumide,a kind of a gastrin receptor antagonist.And the normal cultured gastric cancer cells SGC-7901 and AGS were used in control group.The growth of each group was detected by MTT assay;the cell growth curve was drawn by flow cytometry;the cell cycle of each group was detected by flow cytometry.Annexin V-FITC/PI double staining was used to detect the cell growth of apoptosis.The relative mRNA expression of β-catenin,nuclear factor-P65,mammalian target of rapamycin and glycogen synthase kinase 3 beta in Wnt,NF-κB and PI3K-AKT-MTOR pathways were detected by RT-qPCR.The expression of β-catenin protein was detected by Western blotting.Results After treatment with proglumide,the growth of the cells in the experimental group was lower than that in the control group;and the proportion of S phase cells in the cell cycle was also lower than that in the control group,but the proportion of cells in G0/G1 phase was higher than that in the control group(P<0.05).The percentage of apoptotic cells was also increased after treatment with proglumide(P<0.05).Furthermore,proglumide treatment significantly reduced the expression of β-catenin at both mRNA and protein levels(P<0.05).Conclusion Blocking gastrin receptor can down-regulate the expression of β-catenin,inhibit the cell proliferation and promote the cell apoptosis in gastric cancer cells.
4. Effect of sympathetic overactivity on stroke-associated pneumonia
Yang LI ; Baojun WANG ; Niya MA
International Journal of Cerebrovascular Diseases 2019;27(9):696-699
Stroke-associated pneumonia (SAP), the most common infection complication after stroke, may be associated with immunosuppression caused by post-stroke sympathetic system overactivity. This review discusses the relationship between sympathetic overactivity and SAP. In addition, the evaluation method of sympathetic nervous system activity and the application value of adrenergic receptor blockers are also described.