The E-cadherin repressor slug and progression of human extrahepatic hilar cholangiocarcinoma.

OBJECTIVES: This study explored the expression and function of Slug in human extrahepatic hilar cholangiocarcinoma (EHC) to identify its role in tumor progression. METHODS: The expression of Snail and Slug mRNA in 52 human tissue samples of EHC was investigated. The mRNA of Snail and Slug were quantified using reverse transcriptase-PCR, and correlations with E-cadherin expression and clinicopathological factors were investigated. We then investigated transfection of Slug cDNA in endogenous E-cadherin-positive human EHC FRH0201 cells, selectively induced the loss of E-cadherin protein expression, and then small interfering RNA (siRNA) for inhibition of Slug expression in endogenous Slug-positive human EHC QBC939 cells, selectively induced the loss of Slug protein expression. A Boyden chamber transwell assay was used for invasion. RESULTS: Slug mRNA was overexpressed in 18 cases (34.6%) of EHC compared with adjacent noncancerous tissue. E-Cadherin protein expression determined in the same 52 cases by immunohistochemistry was significantly down-regulated in those cases with Slug mRNA overexpression (P = 0.0001). The tumor and nontumor ratio of Slug mRNA was correlated with nodal metastasis(p = 0.0102), distant metastasis (p = 0.0001)and Survival time(p = 0.0443). However, Snail mRNA correlated with neither E-cadherin expression nor tumor invasiveness. By inhibiting Slug expression by RNA interference, we found that reduced Slug levels upregulated E-cadherin and decreased invasion in QBC939 cell. When the QBC939 cells was infected with Slug cDNA,, significant E-cadherin was downregulated and increased invasion in QBC939 cell. CONCLUSIONS: The results suggested that Slug expression plays an important role in both the regulation of E-cadherin expression and in the acquisition of invasive potential in human EHC. Slug is possibly a potential target for an antitumor therapy blocking the functions of invasion and metastasis in human EHCs.

Shotgun proteome expression profile of microdissected superficial transitional cell carcinoma and biomarker discovery from urine.

The aim of this study was to globally characterize the expression profile of superficial transitional cell carcinoma using shotgun proteome strategy and to discuss the biomarker panel identified from urine. We identified 440 commonly expressed proteins from four samples of superficial transitional cell carcinoma using laser capture microdissection coupled with two-dimensional liquid chromatography tandem mass spectrometry. The identified proteins were further analyzed using bioinformatics tools and compared with the published literature. Compared with the entire list of the International Protein Index, there were 41/22 Gene ontology (GO) terms found to be enriched/depleted within the biological process annotation. GO biological process enrichment/depletion analysis was consistent with the results of urine proteome analysis. Proteins classified under the terms cell adhesion, cell proliferation and cell differentiation are good candidate biomarkers for cancer detection from urine. In conclusion, the present study identified an extensive expression profile in superficial transitional cell carcinoma of the bladder, providing information for the understanding of cancer cell biology and the discovery of a biomarker panel from urine.

[Effect of astrgaloside IV on the long-term consequences of renal ischemia-reperfusion injury in rat].

OBJECTIVE: To observe the effect of astrgaloside IV (Astr) on the long-term consequences of renal ischemia-reperfusion injury (IRI) in rat. METHODS: Fifty-four male Sprague-Dawley rats were randomized into 3 equal groups: IRI group, Astr group, and sham operation group. All rats underwent right nephrectomy and isolation of the left renal artery. The left renal arteries of the IRI group and Astr group were gripped by vascular clamp for 60 minutes and that of the sham operation group was only isolated without gripping. Two milliliters of Astr solution (0.1 g/L) was perfused into the stomach of the rats in the Astr group three days before and after the operation respectively. The rats in the IRI and sham operation groups were perfused with normal saline of the same volume. Four, twelve, and twenty-four weeks after the operation 24-hour urine specimens of the rats were collected to detect the urine protein. At each time point 6 rats from each group were anesthetized and blood was collected from the abdominal aorta to measure the level of serum creatinine (Cr), their left kidneys were taken out to undergo pathological examination and extraction of mRNA. Histochemistry was used to detect the expression of tumor growth factor (TGF)-beta1 protein in the renal tissues. RT-PCR was used to detect the expression of TGF-beta1 mRNA. Collagen staining and immunohistochemistry were used to measure the proportion of collagen positive material to the total area. RESULTS: The level of urine protein was increased progressively, those 12 and 24 weeks after the operation in the IRI group were significantly higher than those in the Astr and sham operation groups (all P < 0.05). The serum Cr 4 weeks after the operation was 36 micromol/L +/- 4 micromol/L, significantly higher than those in the Astr and sham operation groups (31 micromol/L +/- 8 micromol/L and 31 micromol/L +/- 5 micromol/L), and the serum Cr levels 4 weeks 12 and 24 weeks after the operation in the IRI group remained significantly higher than those in the Astr and sham operation groups (all P < 0.05). Collagen staining showed that the glomerular basement membrane, tunica adventitia vasorum, and adventitia of renal tubule were remarkably redder in the IRI than in the Astr and sham operation groups. The expression of TGF-beta1 protein was progressively increased since 12 weeks after the operation in the IRI group, significantly stronger in the Astr and sham operation groups. The expression of TGF-beta1 mRNA was progressively increased since 12 weeks after the operation in the IRI and Astr groups, significantly stronger than that in the sham operation group (P < 0.05). However, the expression of TGF-beta1 mRNA 24 weeks after the operation was significantly stronger in the IRI group than in the Astr group (P < 0.05). CONCLUSION: After renal IRI the probability of development of renal fibrosis increases. Astrgaloside IV markedly ameliorates renal injury by downregulating the TGF-beta1 expression.