Chemical interference with DSIF complex formation lowers synthesis of mutant huntingtin gene products and curtails mutant phenotypes.

Earlier work has shown that siRNA-mediated reduction of the SUPT4H or SUPT5H proteins, which interact to form the DSIF complex and facilitate transcript elongation by RNA polymerase II (RNAPII), can decrease expression of mutant gene alleles containing nucleotide repeat expansions differentially. Using luminescence and fluorescence assays, we identified chemical compounds that interfere with the SUPT4H-SUPT5H interaction and then investigated their effects on synthesis of mRNA and protein encoded by mutant alleles containing repeat expansions in the huntingtin gene (HTT), which causes the inherited neurodegenerative disorder, Huntington's Disease (HD). Here we report that such chemical interference can differentially affect expression of HTT mutant alleles, and that a prototypical chemical, 6-azauridine (6-AZA), that targets the SUPT4H-SUPT5H interaction can modify the biological response to mutant HTT gene expression. Selective and dose-dependent effects of 6-AZA on expression of HTT alleles containing nucleotide repeat expansions were seen in multiple types of cells cultured in vitro, and in a Drosophila melanogaster animal model for HD. Lowering of mutant HD protein and mitigation of the Drosophila "rough eye" phenotype associated with degeneration of photoreceptor neurons in vivo were observed. Our findings indicate that chemical interference with DSIF complex formation can decrease biochemical and phenotypic effects of nucleotide repeat expansions.

[Application of pelvic sentinel lymph node tracing technique in radical prostatectomy].

Pelvic lymph node dissection is an important step in radical prostatectomy (RP). Extended pelvic lymph node dissection (ePLND), currently employed for patients with intermediate- or high-risk PCa, may lead to overtreatment, prolong the operation time, and increase the risks of complications. Sentinel lymph node (SLN) is defined as the first metastasis lymph node from the primary tumor. In addition, SLN distribution is essential for overall lymph node dissection. However, due to the complex and diverse lymphatic drainage pathways and the inaccuracy of lymphatic tracing technology, SLN distribution and dissection have always been controversial. This review focuses on the application of pelvic SLN tracing technique in radical prostatectomy.

[Effects of Targeting lncRNA HOTAIR on the Invasion and Nude Mouse Tumorigenicity of Epithelial Ovarian Cancer Cells].

OBJECTIVE: To explore the effects of shRNA-mediated downregulating lncRNA HOTAIR on the invasion,nude mouse tumorigenicity and snail expression of epithelial ovarian cancer SKOV3 cells. METHODS: The expression of lncRNA HOTAIR was detected by RT-PCR in SKOV3 cells. The shRNA targeting the lncRNA HOTAIR gene was cloned into RNA interference plasmid. The construction shHOTAIR vector was transfected into ovarian cancer SKOV3 cells by lipofectamine 2000,and the stably transfected cells were isolated by G418 and single clone selection. The downregulating expression of lncRNA HOTAIR was detected by quantitative real time PCR(qRT-PCR). The characteristics of shHOTAIR transfected SKOV3 cells were analyzed from the assays of invasion and nude mouse tumorigenicity,as well as the expression of snail and E-cadherin mRNA detected by qRT-PCR,and snail detected by immunohistochemistry and Western blot methods in xenograft tumor,respectively. RESULTS: The lncRNA HOTAIR expression was proved by RT-PCR in SKOV3 cells. The lncRNA HOTAIR expression in shHOTAIR transfected SKOV3 cells was significantly lower than the scramble control (P<0.01). The shHOTAIR transfected SKOV3 cells show that the invasion ability was significantly decreased compared with the scramble control (P<0.01). The nude mouse tumorigenicity,including tumorigenicity mouse number and tumor volume,was significantly decreased compared with the control group (P<0.01). The snail protein expression detected by IHC and Western blot in shHOTAIR-SKOV3 xenograft tumor was significantly decreased compared with the control scramble- SKOV3 group (P<0.05). The lncRNA HOTAIR low expression resulted in increasing E-cadherin and decreasing snail expression detected by qRT-PCR in the shHOTAIR transfected SKOV3 cells of xenograft tumor,compared with the scramble control (P<0.05). CONCLUSION: Targeting lncRNA HOTAIR expression in SKOV3 cells with RNA interference can decrease snail,increase E-cadherin and significantly reduce the invasion and tumorigenicity of epithelial ovarian cancer SKOV3 cells. These results suggest that the lncRNA HOTAIR could be an effective therapeutic target for human epithelial ovarian caner treatment.

c-Met identifies a population of matrix metalloproteinase 9-producing monocytes in peritumoural stroma of hepatocellular carcinoma.

Macrophages (Mϕ) are prominent components of solid tumours and exhibit distinct phenotypes in different microenvironments. Previously, we found that tumours could alter the normal developmental process of Mϕ to trigger transient activation of monocytes in the peritumoural stroma of human hepatocellular carcinoma (HCC). In the present study, we showed that a fraction of monocytes in the peritumoural stroma, but not in HCC cancer nests, expressed surface c-Met molecules. Monocytes exposed to tumours strongly expressed c-Met proteins with kinetics similar to their activation status, and significant correlations were found between c-Met levels and HLA-DR expression on tumour-infiltrating monocytes. NF-κB-mediated autocrine TNF-α stimulated the expression of c-Met on activated monocytes, and by interacting with its ligand hepatocyte growth factor (HGF), c-Met increased the motility and matrix metalloproteinase (MMP) 9-producing capacity of tumour-associated monocytes. The intensity of c-Met expression on tumour-infiltrating monocytes was associated with high mortality and reduced survival of patients with HCC. Therefore, the expression of c-Met on activated monocytes/Mϕ may represent a novel mechanism by which a tumour actively and precisely regulates the distribution and functions of these cells to facilitate disease progression.