Silencing of IQGAP1 by shRNA inhibits the invasion of ovarian carcinoma HO-8910PM cells in vitro

<p>Abstract</p> <p>Background</p> <p>IQGAP1 is a scaffolding protein and overexpressed in many human tumors, including ovarian cancer. However, the contribution of IQGAP1 to invasive properties of ovarian cancer cells remains unknown. Here, we investigated the effect of IQGAP1-specific short hairpin RNA (shRNA) expressing plasmids on metastatic potential of ovarian cancer HO-8910PM cells.</p> <p>Methods</p> <p>We used RT-PCR and Western blot analysis to characterize expression of IQGAP1 in three human ovarian cancer-derived cell lines SK-OV-3, HO-8910 and HO-8910PM. We then determined whether expression of endogenous IQGAP1 correlated with invasive and migratory ability by using an in vitro Matrigel assay and cell migration assay. We further knocked down IQGAP1 using shRNA expressing plasmids controlled by U1 promoter in HO-8910PM cells and examined the proliferation activity, invasive and migration potential of IQGAP1 shRNA transfectants using MTT assay, in vitro Matrigel-coated invasion assay and migration assay.</p> <p>Results</p> <p>IQGAP1 expression level seemed to be closely associated with the enhanced invasion and migration in ovarian cancer cell lines. Levels of both IQGAP1 mRNA and protein were significantly reduced in HO-8910PM cells transfected with plasmid-based IQGAP1-specific shRNAs. RNAi-mediated knockdown of IQGAP1 expression in HO-8910PM cells resulted in a significant decrease in cell invasion and migration.</p> <p>Conclusion</p> <p>Our findings support the hypothesis that IQGAP1 promotes tumor progression and identify IQGAP1 as a potential therapeutic strategy for ovarian cancer and some other tumors with over-expression of the IQGAP1 gene.</p

Characterization of the effects of cross-linking of macrophage CD44 associated with increased phagocytosis of apoptotic PMN

Control of macrophage capacity for apoptotic cell clearance by soluble mediators such as cytokines, prostaglandins and lipoxins, serum proteins, and glucocorticoids may critically determine the rate at which inflammation resolves. Previous studies suggested that macrophage capacity for clearance of apoptotic neutrophils was profoundly altered following binding of CD44 antibodies. We have used a number of different approaches to further define the mechanism by which CD44 rapidly and specifically augment phagocytosis of apoptotic neutrophils. Use of Fab ’ fragments unequivocally demonstrated a requirement for cross-linking of macrophage surface CD44. The molecular mechanism of CD44-augmented phagocytosis was shown to be opsonin-independent and to be distinct from the Mer/protein S pathway induced by glucocorticoids and was not functional for clearance of apoptotic eosinophils. CD44-cross-linking also altered macrophage migration and induced cytoskeletal re-organisation together with phosphorylation of paxillin and activation of Rac2. Investigation of signal transduction pathways that might be critical for CD44 augmentation of phagocytosis revealed that Ca 2+ signalling, PI-3 kinase pathways and altered cAMP signalling were not involved, but did implicate a key role for tyrosine phosphorylation events. Finally, although CD44 antibodies were able to augment phagocytosis of apoptotic neutrophils by murine peritoneal and bone marrow-derived macrophages, we did not observe a difference in the clearance of neutrophils following induction of peritonitis with thioglycollate in CD44-deficient animals. Together, these data demonstrate that CD4

A systematic review of electrical stimulation for pressure ulcer prevention and treatment in people with spinal cord injuries

Context: Electrical stimulation (ES) can confer benefit to pressure ulcer (PU) prevention and treatment in spinal cord injuries (SCI). However, clinical guidelines regarding the use of ES for PU management in SCI remain limited. Objectives: To critically appraise and synthesize the research evidence on ES for PU prevention and treatment in SCI. Method: Review was limited to peer-reviewed studies published in English from 1970 to July 2013. Studies included randomized controlled trials (RCTs), non-RCTs, prospective cohort studies, case series, case control and case report studies. Target population included adults with SCI. Interventions of any type of ES were accepted. Any outcome measuring effectiveness of PU prevention and treatment was included. Methodological quality was evaluated using established instruments. Results: Twenty-seven studies were included, 9/27 studies were RCTs. Six RCTs were therapeutic trials. ES enhanced PU healing in all eleven therapeutic studies. Two types of ES modalities were identified in therapeutic studies (surface electrodes, anal probe), 4 types of modalities in preventive studies (surface electrodes, ES shorts, sacral anterior nerve root implant, neuromuscular electrical stimulation implant). Conclusion: The methodological quality of the studies was poor, in particular for prevention studies. A significant effect of ES on enhancement of PU healing is shown in limited Grade I evidence. The great variability in ES parameters, stimulating locations and outcome measure leads to an inability to advocate any one standard approach for PU therapy or prevention. Future research is suggested to improve the design of ES devices, standardize ES parameters and conduct more rigorous trials