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 peptide-specific 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 HepG2 cells was detected using IFN-γ based enzyme-linked immunospot and lactate dehydrogenase release assays in vitro. RESULTS: A total of six peptides were identified for bindings to HAL-A2 and the GPC3 522-530 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-γ, which were abrogated by treatment with anti-HLA-A2 antibody. The GPC3 522-530-specific CTLs responded to and killed SMMC 7721 and HepG2 cells, instead of GPC3-silenced SMMC 7721 or HepG2 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.

[Effect of xiaokeling concentration fluid on mRNA expression of insulin-like growth factor-1 in sciatic nerve of Streptozotocin-induced diabetic rats].

OBJECTIVE: To investigate the effect of xiaokeling concentration fluid on insulin-like growth factor-1 (IGF-1) mRNA expression in sciatic nerve of Streptozotocin-induced diabetic rats. METHODS: Thirty diabetic rats were randomly divided into model group, mecobalamin tablets group, and xiaokeling concentration fluid group. The IGF-1 mRNA level in sciatic nerve of each group was determined after 8 weeks by relative quantity RT-PCR. RESULTS: The IGF-1 mRNA level in sciatic nerve of diabetic rats between xiaokeling concentration fluid group, mecobalamin tablets group and normal group showed no significant difference ( P = 0.213, P = 0.822, P = 0.304 ), while was significantly higher than that of the model group ( P < 0.05 ). IGF-1 mRNA level was negatively correlated with the level of blood sugar (P < 0.05). CONCLUSION: IGF-1 mRNA level decreased in sciatic nerve of diabetic rats. Xiaokeling concentration fluid can increase the IGF-1 mRNA level in sciatic nerve of diabetic rats. Xiaokeling concentration fluid is involved in the regulation of IGF-1 expression, and probably prevents diabetic peripheral neuropathy from deteriorating.