[Toxic Effect of Nano-ZnO in Liver of Zebrafish].

For acute toxicity test, zebrafish were respectively exposed to the different concentrations of nano-ZnO (0, 0.05, 0.1, 5, 10, 25, 50 mg x L(-1)) for 4, 24 and 96 h. The superoxide dismutase (SOD), malondialdehyde (MDA), and catalase (CAT) in the liver of zebrafish were studied, and the relative expression of Bcl-2, Bax, p53 and MDM2 in liver were also determined. Anatomical structure of the zebrafish liver was determined after exposure to nano-ZnO for 7, 15 and 30 d. Compared with the control group, the liver of the experimental groups showed obvious difference in following aspects: (1) oedema, cytoplastic vacuolation, and pyknotic nucleus were observed; (2) the number of hepatic macrophages deposited and the sinus clearance were increased; (3) the MDA contents and the activity of SOD were increased; (4) however, the activity of CAT was decreased; (5) the mRNA expression level of genes Bax/Bcl-2 ratio and p53 of stressed groups were up-regulated; the mRNA expression level of gene MDM2 down-regulation can be observed in the low concentration groups while the mRNA expression level of gene MDM2 was up-regulated in the high concentration groups. The results suggested that, the oxidative damage of nano-ZnO to the zebrafish liver was caused by the increase of oxidative stress, which made the change of antioxidant enzyme activity, induced the expression of cell apoptosis genetic and cell apoptosis, and caused the change of organizational structure of liver.

Overexpression of ETS2 in human esophageal squamous cell carcinoma.

AIM: To study the expression pattern of ETS2 (erythroblastosis virus oncogene homolog 2) in human esophageal squamous cell carcinoma (ESCC). METHODS: Reverse transcription polymerase chain reaction (RT-PCR) and Northern blot were performed to examine the expression level of ETS2 mRNA in 37 pairs of ESCC tissue samples. Western blot and immunohistochemistry were carried out to check the expression level of ETS2 protein in 30 pairs of ESCC tissue specimens. RESULTS: RT-PCR and Northern blot analysis showed that ETS2 mRNA upregulated in 75.7 % (28/37) examined ESCC tissues relative to matched normal tissues. From those 37 cases, 14 cases were randomly selected to perform Western blot and the results revealed that ETS2 protein overexpressed in 71.4 % (10/14) checked ESCC tissues compared with the corresponding normal tissues. Moreover, the expression patterns of ETS2 protein in those 14 cases were identical to those of ETS2 mRNA displayed by RT-PCR or Northern Blot. Immunohistochemistry analysis showed that the expression level of ETS2 protein rose in 75 % (12/16) tumor epithelial cells contrasted to the normal cells. Altogether the expression level of ETS2 protein increased in 73.3 % (22/30) checked ESCC tissue samples contrary to their normal counterparts. CONCLUSION: The results suggested that ETS2 overexpressed in paired human ESCC tissue samples at both mRNA and protein levels and may be associated with the tumorigenesis of esophagus.