Objective To clarify whether Helicobacter pylori (H. pylori) can promote metastasis of gastric cancer cells via the high-expression of induced B cell specific Moloney murine leukemia virus integration site 1 (Bmi-1). Methods The gastric cancer tissue specimens from 82 patients were collected for this study. The protein and gene expression level of Bmi-1 in gastric adenocarcinoma tissue were detected by immunohistochemistry and real time quantitative PCR, respectively. And meanwhile the correlation between Bmi-1 levels and pathological features, and prognosis of gastric cancer were analyzed retrospectively. Then, the GES-1 cells were transfected with pLPCX-Bmi-1 plasmid and infected with H. pylori respectively. After the Bmi-1 overexpression in GES-1 cells, the invasion ability of the GES-1 cells was detected by Transwell assay, and the cell cycle and apoptosis were detected by flow cytometry. Results The mRNA and protein of Bmi-1 expression in gastric cancer tissues were higher than tumor-adjacent tissue, and the high expression of Bmi-1 was positively correlated with tumor invasion, TNM stage, tumor differentiation, lymph node metastasis and H. pylori infection. When expression of Bmi-1 was up-regulated as a result of H.pylori infection or pLPCX-Bmi-1 transfection, the GES-1 cells had higher invasiveness and lower apoptosis rate with the above treatment respectively. Conclusion H. pylori infection can inhibit the apoptosis of gastric cancer cells and promote their invasion via up-regulating expression of Bmi-1.
Humans ; Cell Line, Tumor ; Helicobacter Infections/genetics* ; Helicobacter pylori ; Lymphatic Metastasis ; Retrospective Studies ; Stomach Neoplasms/pathology* ; Polycomb Repressive Complex 1/genetics*

OBJECTIVE: To investigate the expression of PCGF1 in rectal adenocarcinoma (READ) and the effect of PCGF1 silencing on proliferation READ cells in vitro. METHODS: The UALCAN and ENCORI online databases were used to analyze the expression level of PCGF1 in READ tissues and normal tissues and its association with the clinicopathological parameters and survival outcomes of patients with READ. The expression levels of PCGF1 were detected in two READ cell lines and a normal rectal epithelial cell line (HcoEpiC cells) using qPCR and Western blotting. Lentiviral vectors were used to construct PCGF1-overexpressing and PCGF1-silenced cell lines, and the proliferative activity of the cells was assessed using CCK-8 assay. The effect of PCGF1 silencing on tumor proliferation in vivo was also evaluated by observing tumorigenicity of the cells in nude mice. RESULTS: PCGF1 was highly expressed in READ tissue (P < 0.001), and its expression levels was correlated with READ stage, differentiation and lymph node metastasis (P < 0.001). A high PCGF1 expression level was associated with a poor survival outcome of READ patients (P < 0.05). In SW837 and SW1463 cells, PCGF1 silencing significantly lowered the proliferative activity of the cells both in vitro (P < 0.05) and in nude mice (P < 0.01). CONCLUSION PCGF1 is highly expressed in READ tissue and may potentially serve as a prognostic biomarker as well as a therapeutic target for READ.
Adenocarcinoma/genetics* ; Animals ; Biomarkers ; Cell Line, Tumor ; Cell Proliferation ; Gene Expression Regulation, Neoplastic ; Mice ; Mice, Nude ; Polycomb Repressive Complex 1 ; Sincalide

OBJECTIVE: To explore the molecular mechanism by which miR-218 targeting Bmi-1 inhibits the proliferation of acute promyelocytic leukemia (APL) cells. METHODS: APL cell line HL-60 was transfected by miR-218 and RNA-negative control sequences, respectively. The expression of miR-218 in cells was detected by real-time fluorescence quantitative PCR. The effect of transfected miR-218 on the proliferation of APL cells was detected by MTT assay. Cell apoptosis was detected by flow cytometry. The regulation effect of miR-218 on Bmi-1 expression was determined by Western blot. The correlation of miR-218 expressions with Bmi-1 was analyzed by Spearman test. The targeted relationship between miR-218 and Bmi-1 was verified by luciferase assay. RESULTS: MTT assay showed that the proliferation of HL-60 cells in vitro was inhibited by high expression miR-218 significantly. Flow cytometry showed that the G1 and G2 phase cells increased while the S phase cells decreased after transfected by miR-218. Western blot showed that the level of Bmi-1 protein in HL-60 cells decreased significantly after transfection of miR-218 (P＜0.05). Spearman correlation analysis showed that the mRNA level of miR-218 negatively correlated with the protein content of Bmi-1 (r=-0.326, P＜0.01). Luciferase assay indicated that Bmi-1 could targeted on miR-218 directly. CONCLUSION miR-218 can inhibit the proliferation, metastasis and invasion of APL cells, which can be related with the down-regulated of Bmi-1.
Apoptosis ; Cell Proliferation ; Gene Expression Regulation, Neoplastic ; HL-60 Cells ; Humans ; Leukemia, Promyelocytic, Acute ; genetics ; MicroRNAs ; genetics ; Polycomb Repressive Complex 1 ; genetics

OBJECTIVE: To establish the drug-resistant cell lines of hepatocellular carcinoma (HCC) induced by sorafenib, and to screen out the high expression genes in drug-resistant cell lines of HCC induced by sorafenib, then to explore the genes related to sorafenib resistance in hepatocellular carcinoma. METHODS: The human PLC and Huh7 cell lines were obtained, then the PLC and Huh7 drug-resistant cell lines were induced with sorafenib by using intermittent induction in vitro. CCK8 assay was used to detect the IC50 value of sorafenib for evaluation of drug sensitivity of hepatocellular carcinoma cell lines in PLC and Huh7. All the up regulated genes in PLC and Huh7 drug-resistant cell lines induced by sorafenib were screened out using high-throughput cDNA sequencing (RNA-Seq), Ualcan database was used to analyze the correlations between the up regulated genes in PLC and Huh7 drug-resistant cell lines induced and four clinical biological characteristics of hepatocellular carcinoma, including the gene expressions between normal samples and tumor samples, tumor stage, tumor grade, and patient overall survival, to find the genes that might be involved in the mechanism of sorafenib resistance of hepatocellular carcinoma. RESULTS: All the up regulated genes detected by the using high-throughput cDNA sequencing (RNA-Seq) in PLC and Huh7 drug-resistant cell lines were further screened out by following conditions:(1) genes co-expressed in PLC and Huh7 drug-resistant cells induced by sorafenib, (2) the fold change was more than 4 times and the difference was statistically significant (P <0.05), the top 12 up regulated genes in PLC and Huh7 drug-resistant cell lines were found, which were TPSG1, CBX4, CLC, CLEC18C, LGI4, F2RL1, S100A6, HABP2, C15ORF48, ZG16, FOLH1, and EPCAM. Compared with the correlations between the twelve genes and the clinical biological characteristics by Ualcan database, the potentially significant gene CBX4 was screened out. CONCLUSION The human PLC and Huh7 drug-resistant cell lines of hepatocellular carcinoma induced by sorafenib were successfully established. CBX4, the gene related to sorafenib resistance in hepatocellular carcinoma, was screened out by the high-throughput cDNA sequencing (RNA-Seq) and further analysis using Ualcan database, which is providing a powerful basis for further research on the mechanism of sorafenib resistance of hepatocellular carcinoma.
Antineoplastic Agents/therapeutic use* ; Carcinoma, Hepatocellular/drug therapy* ; Cell Line, Tumor ; Cell Proliferation ; Drug Resistance, Neoplasm ; Humans ; Ligases ; Liver Neoplasms/drug therapy* ; Polycomb-Group Proteins ; Serine Endopeptidases ; Sorafenib/therapeutic use*

OBJECTIVE: To study whether the Bmi-1 gene can be a biomarker for analysis of clinical risk stratification and prognosis of ALL patients. METHODS: The expression level of Bmi-1 gene in bone marrow samples from 127 cases of newly diagnosed ALL was detected by qRT-PCR, at the same time the expression level of Bmi-1 protein in bone marrow samples from above-mentioned cases was detected by Western blot. The collected samples were divided into 3 groups: high, intermediate and low risk according to clinical risk stratfication, the relationship between Bmi-1 expression and risk grade of ALL patients was analyzed; at the same time the collected samples were divided into 2 groups: prednisone good response (PGR) and prednisone poor respouse (PPR) according to the sensitivity of prednison test, and the sensitivily to prednisone in 2 groups was compared; moreover, the collected samples were divided into 2 groups: high level and low level according to median of Bmi-1 level, and the relation of Bmi-1 level with prognosis of patients was analyzed by using the Kaplan-Meier method. RESULTS: The expression level of Bmi-1 in low risk group was lowest, while that in high risk group was highest, however that in intermediat risk group was between the low and high risk groups, statistical analysis showed significant difference (P＜0.05). The expression level of Bmi-1 in PPR group was significantly higher than that in PGR group (P＜0.001). The Kaplan-Meier analysis showed that the RFS rate in Bmi-1 high expression group was significantly lower than that in Bmi-1 low expression group (73.0% vs 90.6%) (P＜0.001). CONCLUSION The Bmi-1 can be used as a molecular marker for the analysis of chinical risk and prognosis of pediatric ALL.
Biomarkers ; Child ; Humans ; Kaplan-Meier Estimate ; Polycomb Repressive Complex 1 ; metabolism ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; Prednisone ; Prognosis

OBJECTIVE: To investigate the effect of Bmi-1 gene silence on the proliferation ability of K562 cells in vitro and in vivo, and to explore the relation of molecular mechanism between proliferation ability of K562 cells in vitro and in vivo with PTEN/pAKT signaling pathway. METHODS: The Bmi-1 small interference RNA (siRNA) sequences were transfected into K562 cells for decreasing Bmi-1 expression. The effect of Bmi-1 siRNA on the proliferation of K562 cells in vitro and in vivo was detected by MTT method and colony-forming test, the effect of Bmi-1 siRNA on the tumorogenicity of K562 cells was observed by subcutaneous inoculation of K562 cells, LY294002 and Bpv treated K562 cells in nude mice, the expression of Bmi-1, PTEN and pAKT proteins were detected by Western blot. RESULTS: The Bmi-1 siRNA could inhibit the proliferation activity, colony-forming and tumor-forming abilities of K562 cells. After the silence of Bmi-1 gene, the PTEN expression in Bmi-1 gene-silenced group was significantly enhanced. While the pAKT expression in Bmi-1 gene-silenced group was significantly reduced; after the K562 cells were treated with LY294002 (an inhibitor of pAKT), the pAKT expression colony-forming and tumor forming abilities were reduced in comparison with untreated K562 cells; after the K562-S1 cells were treated with Bpv (an inhibitor of PTEN), the PTEN expression decreased, while the pAKT expression, colony forming and tumor-forming abilities were restored. CONCLUSION The Bmi-1 gene possibly involves in regulation of K562 proliferation in vivo and in vitro, the effect of PTEN/pAKT signaling pathway maybe one of molecular mechanisms mediating this regulation.
Animals ; Apoptosis ; Cell Proliferation ; Humans ; K562 Cells ; Leukemia ; Mice ; Mice, Nude ; PTEN Phosphohydrolase ; Polycomb Repressive Complex 1 ; Proto-Oncogene Proteins c-akt ; RNA, Small Interfering ; Signal Transduction

BACKGROUND AND OBJECTIVES: Human amniotic fluid-derived mesenchymal stem cells (AF-MSCs) may be a valuable source for cardiovascular tissue engineering and cell therapy. The aim of this study is to verify angiotensin II and transforming growth factor-beta 1 (TGF-β1) as potential cardiomyogenic differentiation inducers of AF-MSCs. METHODS AND RESULTS: AF-MSCs were obtained from amniocentesis samples from second-trimester pregnant women, isolated and characterized by the expression of cell surface markers (CD44, CD90, CD105 positive; CD34 negative) and pluripotency genes (OCT4, SOX2, NANOG, REX1). Cardiomyogenic differentiation was induced using different concentrations of angiotensin II and TGF-β1. Successful initiation of differentiation was confirmed by alterations in cell morphology, upregulation of cardiac genes-markers NKX2-5, TBX5, GATA4, MYH6, TNNT2, DES and main cardiac ion channels genes (sodium, calcium, potassium) as determined by RT-qPCR. Western blot and immunofluorescence analysis revealed the increased expression of Connexin43, the main component of gap junctions, and Nkx2.5, the early cardiac transcription factor. Induced AF-MSCs switched their phenotype towards more energetic and started utilizing oxidative phosphorylation more than glycolysis for energy production as assessed using Agilent Seahorse XF analyzer. The immune analysis of chromatin-modifying enzymes DNMT1, HDAC1/2 and Polycomb repressive complex 1 and 2 (PRC1/2) proteins BMI1, EZH2 and SUZ12 as well as of modified histones H3 and H4 indicated global chromatin remodeling during the induced differentiation. CONCLUSIONS: Angiotensin II and TGF-β1 are efficient cardiomyogenic inducers of human AF-MSCs; they initiate alterations at the gene and protein expression, metabolic and epigenetic levels in stem cells leading towards cardiomyocyte-like phenotype formation.
Amniocentesis ; Amniotic Fluid ; Angiotensin II ; Angiotensins ; Blotting, Western ; Calcium ; Cell Differentiation ; Cell- and Tissue-Based Therapy ; Chromatin ; Chromatin Assembly and Disassembly ; Connexin 43 ; Epigenomics ; Female ; Fluorescent Antibody Technique ; Gap Junctions ; Glycolysis ; Histones ; Humans ; Ion Channels ; Mesenchymal Stromal Cells ; Muscle Cells ; Oxidative Phosphorylation ; Phenotype ; Polycomb Repressive Complex 1 ; Pregnant Women ; Smegmamorpha ; Stem Cells ; Tissue Engineering ; Transcription Factors ; Up-Regulation

B lymphoma Moloney murine leukemia virus insertion region 1 (BMI1), a core member of polycomb repressive complex 1 (PRC1), has been intensely investigated in the field of cancer epigenetics for decades. Widely known as a critical regulator in cellular physiology, BMI1 is essential in self-renewal and differentiation in different lineages of stem cells. BMI1 also plays a significant role in cancer etiology for its involvement in pathological progress such as epithelial-mesenchymal transition (EMT) and cancer stem cell maintenance, propagation, and differentiation. Importantly, overexpression of BMI1 is predictive for drug resistance, tumor recurrence, and eventual therapy failure of various cancer subtypes, which renders the pharmacological targeting at BMI1 as a novel and promising therapeutic approach. The study on prostate cancer, a prevalent hormone-related cancer among men, has promoted enormous research advancements in cancer genetics and epigenetics. This review summarizes the role of BMI1 as an oncogenic and epigenetic regulator in tumor initiation, progression, and relapse of prostate cancer.
Animals ; Gene Expression Regulation, Neoplastic ; Humans ; Lymphoma, B-Cell/genetics* ; Male ; Mice ; Moloney murine leukemia virus/genetics* ; Mutagenesis, Insertional/genetics* ; Polycomb Repressive Complex 1/genetics* ; Prostatic Neoplasms/genetics*

Humans ; Models, Molecular ; Repressor Proteins ; chemistry ; metabolism ; Retinoblastoma-Binding Protein 4 ; chemistry ; metabolism

CRISPR-Cas Systems ; Embryo, Mammalian ; Gene Editing ; methods ; HEK293 Cells ; Humans ; Polycomb Repressive Complex 1 ; genetics ; Zygote