Expression of ornithine decarboxylase in precancerous and cancerous gastric lesions

AIM: To investigate the expression of ornithine decarboxylase (ODC) in precancerous and cancerous gastric lesions. METHODS: We studied the expression of ODC in gastric mucosa from patients with chronic superficial gastritis (CSG,n = 32),chronic atrophic gastritis CAG,n = 43; 15 with and 28 without intestinal metaplasia (IM),gastric dysplasia (DYS,n = 11) and gastric cancer (GC,n = 48) tissues using immunohistochemical staining. All 134 biopsy specimens of gastric mucosa were collected by gastroscopy. METHODS: The positive rate of ODC expression was 34.4%,42.9%,73.3%,81.8% and 91.7% in cases with CSG,CAG without IM,CAG with IM,DYS and GC,respectively (P < 0.01),The positive rate of ODC expression increased in the order of CSG < CAG (without IM) < CAG (with IM) < DYS and finally,GC. In addition,ODC positive immunostaining rate was lower in well-differentiated GC than in poorly-differentiated GC (P < 0.05). CONCLUSION: The expression of ODC is positively correlated with the degree of malignity of gastric mucosa and development of gastric lesions. This finding indicates that ODC may be used as a good biomarker in the screening and diagnosis of precancerous lesions.

Glypican-3-specific cytotoxic T lymphocytes induced by human leucocyte antigen-A*0201-restricted peptide effectively kill hepatocellular carcinoma cells in vitro

Objective: To investigate potential human leucocyte antigen(HLA)-A2-restricted epitope peptides of glypican-3(GPC3) and determine the cytotoxicity of peptidespecific cytotoxic T lymphocytes(CTLs) against hepatocellular carcinoma(HCC) cells.Methods: The potential HLA-A*0201-restricted GPC3 peptides were screened using computer algorithms, T2 cell-binding affinity and stability of peptide/HLA-A*0201 complex assay. The peptide-specific CTLs were generated and their cytotoxicity against GPC3+SMMC 7721 and Hep G2 cells was detected using IFN-g based enzymelinked immunospot and lactate dehydrogenase release assays in vitro.Results: A total of six peptides were identified for bindings to HAL-A2 and the GPC3522–530 and GPC3 229–237 peptides with HLA-A*0201 molecules displayed high binding affinity and stability. The CTLs induced by the GPC3 522–530 or positive control GPC3 144–152 peptide responded to the peptide by producing IFN-g, which were abrogated by treatment with anti-HLA-A2 antibody. The GPC3 522–530-specific CTLs responded to and killed SMMC 7721 and Hep G2 cells, instead of GPC3-silenced SMMC7721 or Hep G2 cells. GPC3 522–530-specific CTLs response to HCC cells was blocked by anti-HLA-A2 antibody.Conclusions: The GPC3 522–530 peptide contains antigen-determinant and its specific CTLs can effectively kill HCC in a HLA-A2-restricted and peptide-dependent manner. Our findings suggest that this peptide may be valuable for development of therapeutic vaccine.

Effects of TAM-derived exosomes on migration and invasion of MDA-MB- 231 cells in triple negative breast cancer

Objective:To investigate the effects of exosomes derived from tumor-associated macrophages(TAMs)on migration and invasion of MDA-MB-231 cells in triple negative breast cancer.Methods:The MDA-MB-231 cells,a human breast cancer cell line,were divided into the experimental group and the blank control group.The exosomes were isolated from the supernatant of human peripheral blood mononuclear cells(THP-1)by a multi-step ultracentrifugal procedure.The effects of exosomes on migration and invasion of MDAMB-231 cells were studied by endocytosis assay of exosomes,Transwell migration assay and Celigo scratch assay.Results:Exosomes were ingested and endocytosed by MDAMB-231 cells,brought into the cytoplasm at 3h and enriched significantly at 6h.Compared with the blank control group,the number of metastatic cells in the Transwell compartment(241±3.35)and its variation relative to normal cells(144±2.33)in the experimental group were significantly increased(P<0.05).The 24 h migration rate of MDA-MB-231 cells treated with exosomes in the scratch assay showed similar results(39.86±3.47 in the experimental group vs.24.48±2.97 in the control group,P<0.05).Conclusion:TAM-derived exosomes can be ingested and endocytosed by MDA-MB-231 cells,and promote their migration and invasion in vitro.

Construction and validation of prognostic model of hepatocellular carcinoma based on epigenetic factors

Objective:To explore the targeting relationship between miRNA and epigenetic factors related to the prognosis of hepatocellular carcinoma(HCC),and to identify the potential impact of miRNA targeted epigenetic factors on the prognosis of HCC.Methods:The mRNA and miRNA sequencing data of all HCC samples were downloaded from the tumor Genome Atlas(TCGA)database,and the R program was used to analyze the difference of the sequencing data.The data of survival time,survival status and differential expression of miRNA were combined,and the risk score model of miRNA was constructed by univariate and multivariate Cox regression.The miRNA target genes and all the corresponding Epigenetic factors were predicted,and the differentially expressed Epigenetic factors(DEEFs)were screened.Then,the regulatory network of miRNA targeting deefs was established,the apparent factors in the network were enriched and analyzed,and the core genes in the protein-protein interaction(PPI)network and selection network were constructed.Finally,the relationship between the apparent factors and the prognosis of patients was analyzed and verified by Kaplan Meier(K-M)method.Results:305 differentially expressed miRNAs were identified using EDGE algorithm.After Cox analysis,hsa-miR-139-5p,hsa-miR-101-3p and hsa-miR-7-5p(miR-139-5p,miR-101-3p and miR-7-5p)were finally screened as the Overall survival of HCC patients(Overall survival,OS).In addition,34 DEEFs targeted by miRNAs were identified,among which EZH2,PKM,HJURP and CHEK1 had a significant impact on the survival of hepatocellular carcinoma.Conclusion:In this study,we successfully established a prognostic model of hepatocellular carcinoma miRNA-targeted epigenetics,and screened out epigenetic factors that are significantly related to the prognosis of hepatocellular carcinoma.It provides new potential prognostic biomarkers and therapeutic targets for HCC treatment,and lays a theoretical foundation for the follow-up basic research of HCC.