Journal Article

Animals; Apoptosis; Benzoxazines; Bioware; Breast Neoplasms; Cannabinoids; Cell Cycle; Cell Growth Processes; Cell Line, Tumor; Cell Movement; Cyclooxygenase 2; Dinoprostone; Female; Humans; Immunohistochemistry; Lung Neoplasms; Male; Mammary Neoplasms, Experimental; MDA-MB-231-D3H2LN cells; Mice; Mice, Inbred C3H; Mice, SCID; Mice, Transgenic; Microscopy, Confocal; Morpholines; Naphthalenes; Neoplasm Metastasis; Neovascularization, Pathologic; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2; RNA, Small Interfering; Signal Transduction; Transfection; Xenograft Model Antitumor Assays

Cannabinoids have been reported to possess antitumorogenic activity. Not much is known, however, about the effects and mechanism of action of synthetic nonpsychotic cannabinoids on breast cancer growth and metastasis. We have shown that the cannabinoid receptors CB1 and CB2 are overexpressed in primary human breast tumors compared with normal breast tissue. We have also observed that the breast cancer cell lines MDA-MB231, MDA-MB231-luc, and MDA-MB468 express CB1 and CB2 receptors. Furthermore, we have shown that the CB2 synthetic agonist JWH-133 and the CB1 and CB2 agonist WIN-55,212-2 inhibit cell proliferation and migration under in vitro conditions. These results were confirmed in vivo in various mouse model systems. Mice treated with JWH-133 or WIN-55,212-2 showed a 40% to 50% reduction in tumor growth and a 65% to 80% reduction in lung metastasis. These effects were reversed by CB1 and CB2 antagonists AM 251 and SR144528, respectively, suggesting involvement of CB1 and CB2 receptors. In addition, the CB2 agonist JWH-133 was shown to delay and reduce mammary gland tumors in the polyoma middle T oncoprotein (PyMT) transgenic mouse model system. Upon further elucidation, we observed that JWH-133 and WIN-55,212-2 mediate the breast tumor-suppressive effects via a coordinated regulation of cyclooxygenase-2/prostaglandin E2 signaling pathways and induction of apoptosis. These results indicate that CB1 and CB2 receptors could be used to develop novel therapeutic strategies against breast cancer growth and metastasis.

Journal Article

Animals; B16-F10-luc-G5 cells; Bioware; Cell Division; Cell Line, Tumor; Collagen; Humans; Injections; Male; Mice; Mice, Nude; RNA Interference; RNA Stability; RNA, Small Interfering; Testicular Neoplasms; Transduction, Genetic; Xenograft Model Antitumor Assays

Silencing gene expression by siRNAs is rapidly becoming a powerful tool for the genetic analysis of mammalian cells. However, the rapid degradation of siRNA and the limited duration of its action call for an efficient delivery technology. Accordingly, we describe here that Atelocollagen complexed with siRNA is resistant to nucleases and is efficiently transduced into cells, thereby allowing long-term gene silencing. Site-specific in vivo administration of an anti-luciferase siRNA/Atelocollagen complex reduced luciferase expression in a xenografted tumor. Furthermore, Atelocollagen-mediated transfer of siRNA in vivo showed efficient inhibition of tumor growth in an orthotopic xenograft model of a human non-seminomatous germ cell tumor. Thus, for clinical applications of siRNA, an Atelocollagen-based non-viral delivery method could be a reliable approach to achieve maximal function of siRNA in vivo.

Journal Article

Animals; B16-F10-luc-G5 cells; Bioware; Diagnostic Imaging; Luminescence; Melanoma, Experimental; Mice; Mice, Inbred BALB C; Molecular Dynamics Simulation

AIM The aim of this study was to evaluate the veracity and sensitivity of in-vivo imaging system (IVIS) for inspection of tumor dynamic morphology. METHODS Mouse melanoma cells (B16-F10-luc-G5) in 100 mL media were seeded into a 96-well plate by 1:2 serial dilution from 10000 cells (well #1) to 78 cells (well #8). The plate was imaged using IVIS system to evaluate its sensitivity for luminescence. Ten Bablc mice with tumor cells were injected subcutaneously (1 x 10(5) in 100 mL) and tumor luminescence was detected by IVIS at Day 0, Day 3, Day 5, Day 7 and Day 9. RESULTS As few as 78 tumor cells were detectable by IVIS. A strong correlation between number of tumor cells and bioluminescence (R2=0.99) was also demonstrated. Tumor luminescence were observed in all mice by IVIS at all days, and there was significant difference (P<0.01) between each two days from Day 0 to Day 9. Moreover, tumor dynamic morphology could be monitored by IVIS when it is invisible. CONCLUSION Compared with conventional methods, with high veracity and sensitivity, IVIS system should be recommended as an effective method for inspection of tumor dynamic morphology.

Journal Article

Animals; Bacterial Proteins; Biofilms; Bioware; Catheterization, Central Venous; Male; Mice; Point Mutation; Sigma Factor; Staphylococcal Infections; Staphylococcus aureus; Virulence; Xen29

The impact of the alternative sigma factor sigma B (SigB) on pathogenesis of Staphylococcus aureus is not conclusively clarified. In this study, a central venous catheter (CVC) related model of multiorgan infection was used to investigate the role of SigB for the pathogenesis of S. aureus infections and biofilm formation in vivo. Analysis of two SigB-positive wild-type strains and their isogenic mutants revealed uniformly that the wild-type was significantly more virulent than the SigB-deficient mutant. The observed difference in virulence was apparently not linked to the capability of the strains to form biofilms in vivo since wild-type and mutant strains were able to produce biofilm layers inside of the catheter. The data strongly indicate that the alternative sigma factor SigB plays a role in CVC-associated infections caused by S. aureus.

Journal Article

Animals; Bacteroides fragilis; Diagnostic Imaging; Disease Progression; Escherichia coli; Luciferases, Bacterial; Luminescent Agents; Male; Peritoneal Lavage; Peritonitis; Rats; Rats, Wistar; Xen14

BACKGROUND Bacterial peritonitis is a life-threatening abdominal infection associated with high morbidity and mortality. The rat is a popular animal model for studying peritonitis and its treatment, but longitudinal monitoring of the progression of peritonitis in live animals has been impossible until now and thus required a large number of animals. Our objective was to develop a noninvasive in vivo imaging technique to monitor the spatiotemporal spread of bacterial peritonitis. METHODS Peritonitis was induced in 8 immunocompetent male Wistar rats by placing fibrin clots containing 5x10(8) cells of both Bacteroides fragilis (American Type Tissue Culture [ATCC)] 25,285 and bioluminescent Escherichia coli Xen14. After 1 or 2 days, infected clots were removed and open abdomen lavage was performed. In vivo bioluminescent imaging was used to monitor the spread of peritonitis. RESULTS Bioluminescent in vivo imaging showed an increase in the area of spread, and the number of E. coli tripled into the rat's abdominal cavity on day 1 after clot insertion; however, on day 2, encapsulation of the clot confined bacterial spread. Bioluminescent E. coli respread over the peritoneal cavity after lavage; within 10 days, however, in vivo imaging showed a decrease of 3-4 orders of magnitude in bacterial load. CONCLUSION Bioluminescent in vivo imaging can be effectively used to monitor the spatiotemporal behavior of the peritonitis during 3 different stages of the disease process: initiation, treatment, and follow-up. Imaging allows researchers to repeatedly image the same animal, thereby reducing variability and providing greater confidence in determining treatment efficacies for therapeutic interventions using a small number of animals.