Gene silencing by lentivirus-mediated delivery of integrin β4 shRNA inhibits the growth of subcutaneous xenografts of human non-small cell lung carcinoma H460SM cells in nude mice / 肿瘤

Objective: To investigate the inhibitory effect of gene silencing by lentivirus-mediated delivery of ITGB4 (integrin β4) shRNA on the growth of subcutaneous xenografts of human NSCLC (nonsmall cell lung carcinoma) H460SM cells in nude mice. Methods: The expression levels of ITGB4 mRNA and protein in different human NSCLC cell lines were detected by RFQ-PCR (real-time fluorogenic quantitative- PCR) and Western blotting, respectively. Lentivirus-mediated delivery of ITGB4 shRNA was used to inhibit the expression of ITGB 4 gene in H460SM cells, and the expression of ITGB4 was determined by RFQ-PCR and Western blotting to evaluate the gene-silencing efficiency. The nude mice were randomly inoculated subcutaneously with H460SM cells without infection (H460SM-NS cells) or H460SM-68/H460SM-71 cells stably expressing ITGB4 shRNA. The xenograft tumor volume was estimated from tumor diameter and the mouse weight was measured every other day. The growth of the xenograft tumor was also compared. Finally, the mice were sacrificed, and the subcutaneous xenograft tumor was dissected to measure the tumor size and its weight. Results: Most human NSCLC cell lines expressed ITGB4. The expression levels of ITGB4 were significantly higher in H460SM and NCI-H460 cells than in NCI-H661 cells (P < 0.01). A significantly higher level of ITGB4 expression was observed in H460SM cells as compared with their parental NCI-H460 cells (P < 0.01). A significant down-regulation of ITGB4 expression was also observed in H460SM cells infected with ITGB4 shRNA as compared with H460SM cells infected with negative control shRNA (P < 0.01). The growth of subcutaneous xenografts of H460SM cells by knockdown of ITGB 4 in nude mice obviously slowed down (P < 0.01). Conclusion: ITGB4 expression may be associated with tumorigenesis, invasiveness and metastasis of human NSCLC H460SM cells. Inhibition of ITGB4 expression can reduce the growth of subcutaneous xenografts of human NSCLC H460SM cells in nude mice. Copyright © 2012 by TUMOR.

TiO2 nanotube stimulate chondrogenic differentiation of limb mesenchymal cells by modulating focal activity

Vertically aligned, laterally spaced nanoscale titanium nanotubes were grown on a titanium surface by anodization, and the growth of chondroprogenitors on the resulting surfaces was investigated. Surfaces bearing nanotubes of 70 to 100 nm in diameter were found to trigger the morphological transition to a cortical actin pattern and rounded cell shape (both indicative of chondrocytic differentiation), as well as the up-regulation of type II collagen and integrin beta4 protein expression through the down-regulation of Erk activity. Inhibition of Erk signaling reduced stress fiber formation and induced the transition to the cortical actin pattern in cells cultured on 30-nm-diameter nanotubes, which maintained their fibroblastoid morphologies in the absence of Erk inhibition. Collectively, these results indicate that a titanium-based nanotube surface can support chondrocytic functions among chondroprogenitors, and may therefore be useful for future cartilaginous applications.

Expression and their clinical significance of uPA and integrin?4 in papillary thyroid cancer / 中国耳鼻咽喉头颈外科

OBJECTIVE To investigate the expression and their clinical significance of uPA (urokinase type plasminogen activator) and integrin?4 in papillary thyroid cancer. METHODS The levels of uPA and integrin?4 were determined by Immunohistochemistry technique (S-P method) in 36 specimens from patients with papillary thyroid cancer, 30 specimens from benign thyroid tumor and normal thyroid tissues adjacent to benign thyroid tumor. RESULTS The levels of uPA and integrin?4 in benign thyroid tumor were significantly higher than that in normal tissue adjacent to benign thyroid tumor (P