1.Remodeling characteristics and construction of a survival prediction model based on enhancers and regulome in intestinal type gastric cancer
Xu CHEN ; Zhaole CHU ; Bijun QIN ; Biying LIU ; Xianfeng LI ; Tao WANG ; Wenkang LIU ; Bin WANG
Journal of Army Medical University 2024;46(7):695-704
Objective To explore the genome-wide distribution of histone H3K27ac in intestinal type gastric cancer,analyze remodeling features of enhancers and regulome and construct a prediction model for prognosis.Methods H3K27ac CUT&Tag sequencing and RNA sequencing were performed in intestinal type gastric cancer tissues from 15 patients and normal gastric mucosa tissues from 18 healthy volunteers.Bioinformatics analysis was performed to identify the differences in genome distribution of H3K27ac modifications.Based on the distribution characteristics of H3K27ac,the enhancer elements were identified and the remodeling characteristics of enhancer and related regulome were explored.The prediction model for prognosis based on enhancer related target genes was constructed by univariate Cox and multivariate Cox regression analyses.Results The histone H3K27ac modification was mainly distributed in the enhancer region and displayed no significant differences in the genomic distribution patterns between normal and cancer tissues.Compared with normal gastric mucosa,the level of enhancer H3K27ac modification was higher in intestinal type gastric cancer.A total of 8847 enhancers with increased activity in intestinal type gastric cancer were identified,accounting for 8.3%of all enhancers,which might promote malignant behaviors such as proliferation and adhesion of gastric cancer cells.A prognosis-predicting model established based on a panel of 6 genes that upregulated by the acquired enhancer in cancers,which was able to predict the overall survival of patients.Conclusion Enhancer remodeling is one of the significant epigenetic features of intestinal type gastric cancer.These enhancers may drive malignant growth and adhesion of cancer cells by upregulating the expression of MYC,E2F3 and other genes.A prognosis model based on enhancer target genes is constructed.
2.Expression of peroxisome proliferators-activated receptor in glioma and its effect on the growth of human glioma cells.
Yan SHI ; Wenkang LUAN ; Tao TAO ; Jiajia WANG ; Jin QIAN ; Qingsheng DONG ; Ning LIU ; Yongping YOU
Chinese Journal of Medical Genetics 2014;31(3):317-321
OBJECTIVETo study the expression of peroxisome proliferators-activated receptor (PPAR) in human glioma tissue and its influence on tumor growth.
METHODSExpression of PPAR mRNA in glioma tissue was determined by real-time reverse transcription polymerase chain reaction (RT-PCR). Subsequently, MTT (3-(4, 5)-dimethylthiahiazo(-z-y1)-3, 5-di-phenytetrazoliumromide) assay, flow cytometry, reactive oxygen species assay kit and Western blotting were used to assay U87 cells with agonist activity of PPAR.
RESULTSThe data demonstrated that the expression of PPAR in glioma was low and negatively correlated with its pathological grade. Activation of PPAR suppresses tumor cell proliferation, delays the cell cycle at G1 phrase, and induces apoptosis and accumulation of reactive oxygen species (ROS) in U87 cells.
CONCLUSIONThe expression of PPAR mRNA in human glioma was low. PPAR protein plays a critical role in the progression of glioma via the PPAR signal pathway.
Apoptosis ; Cell Cycle Checkpoints ; Cell Line, Tumor ; Cell Proliferation ; Gene Expression ; Glioma ; genetics ; metabolism ; physiopathology ; Humans ; PPAR alpha ; genetics ; metabolism ; Signal Transduction
3.Protective effect of folic acid against cholestatic liver injury in mice caused by bis(2-ethylhexyl) phthalate exposure
Mengzhen HOU ; Yun YU ; Qianqian HUANG ; Lun ZHANG ; Wenkang TAO ; Yue JIANG ; Jianqing WANG
Journal of Clinical Hepatology 2024;40(10):2062-2069
ObjectiveTo investigate the protective effect of folic acid against cholestatic liver injury in mice induced by bis(2-ethylhexyl) phthalate (DEHP) exposure and its mechanism. MethodsICR mice were randomly divided into control group, high-dose folic acid (H-FA) group, DEHP group, DEHP+low-dose folic acid (DEHP+L-FA) group, and DEHP+high-dose folic acid (DEHP+H-FA) group, with 6 mice in each group. The mice in the H-FA group, the DEHP+L-FA group, and the DEHP+H-FA group were given folic acid by gavage at the corresponding dose, and those in the control group and the DEHP group were given an equal volume of PBS solution by gavage. After 2 hours, the mice in the DEHP group, the DEHP+L-FA group, and the DEHP+H-FA group were given corn oil containing 200 mg/kg DEHP, and those in the control group and the H-FA group were given an equal volume of pure corn oil, by gavage for 4 weeks. Body weight and food intake were recorded every day, and blood and liver tissue samples were collected. A biochemical analyzer was used to measure the serum levels of total bile acid (TBA) and alkaline phosphatase(ALP); HE staining was used to observe the histopathological changes of liver tissue; kits were used to measure the content of malondialdehyde (MDA) and superoxide dismutase (SOD) in the liver; LC-MS/MS was used to measure serum bile acid profiles; Western blot was used to measure the expression levels of proteins associated with hepatic bile acid metabolism. A one-way analysis of variance was used for comparison of continuous data between multiple groups, and the least significant difference t-test was used for further comparison between two groups. ResultsCompared with the control group, the daily food intake of the mice in the DEHP group decreased significantly, and the body weight decreased significantly from day 10 (P<0.05), and compared with the DEHP group, the DEHP+L-FA group and the DEHP+H-FA group had basically unchanged body weight and daily food intake (P>0.05). Compared with the control group, the DEHP group had significant increases in liver weight index and the serum levels of TBA and ALP (all P<0.05), with enlarged portal area, bile duct deformity and hyperplasia, and a small amount of inflammatory cell infiltration in liver tissue; compared with the DEHP group, the DEHP+L-FA group and the DEHP+H-FA group had a significant reduction in liver weight index (P<0.01), and the DEHP+H-FA group had significant reductions in the serum levels of TBA and ALP (P<0.05), with a significant improvement in liver histomorphology and structure after folic acid intervention. Compared with the control group, the DEHP group had a significant reduction in the content of SOD (P<0.05) and a significant increase in the content of MDA in the liver (P<0.01), and compared with the DEHP group, the DEHP+H-FA group had significant reductions in the content of MDA and SOD (P<0.05). Compared with the control group, the DEHP group had significant increases in the serum levels of α-muricholic acid (α-MCA),β- muricholic acid (β-MCA),deoxycholic acid (DCA), lithocholic acid (LCA), taurocholic acid (TCA), taurodeoxycholic acid (TDCA), tauroursodeoxycholic acid (TUDCA), tauro-β-muricholic acid (T-β-MCA), tauro-α-muricholic acid (T-α-MCA), taurohyodeoxycholic acid (THDCA), and taurolithocholic acid (TLCA) (P<0.05) and a significant reduction in ursodeoxycholic acid (UDCA)(P<0.05); compared with the DEHP group, the DEHP+H-FA group had significant reductions in the serum levels of DCA, LCA, TCA, TDCA, TUDCA, T-β-MCA, T-α-MCA, THDCA, and TLCA (P<0.05). Compared with the control group, the DEHP group had significant increases in the protein expression levels of FXR and CYP3A11 in the liver (P<0.01) and significant reductions in the protein expression levels of CYP7A1 and MRP2 (P<0.01); compared with the DEHP group, the DEHP+L-FA group and the DEHP+H-FA group had significant reductions in the protein expression levels of FXR and CYP3A11 in the liver (P<0.05) and a significant increase in the protein expression level of MRP2 (P<0.05), and the DEHP+H-FA group had a significant increase in the protein expression level of CYP7A1 (P<0.05). ConclusionFolic acid has a protective effect against cholestatic liver injury in mice induced by DEHP exposure, possibly by regulating bile acid synthesis, catabolism, and transport and maintaining bile acid homeostasis.