orabase and Osteosarcoma

A bioactive glass series (0.42SiO2-0.10Na2O-0.08CaO-(0.40-X)ZnO-(X)Ga2O3) was incorporated into carboxymethyl cellulose (CMC)/dextran (Dex) hydrogels in three different amounts (0.05, 0.10, and 0.25m(2)), and the resulting composites were characterized using transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and (13)C Cross Polarization Magic Angle Spinning Nuclear Magnetic Resonance (CP MAS-NMR). Composite extracts were also evaluated in vitro against MG-63 osteosarcoma cells. TEM confirmed glass distribution throughout the composites, although some particle agglomeration was observed. DSC revealed that glass composition and content did have small effects on both Tg and Tm. MAS-NMR revealed that both CMC and Dex were successfully functionalized, that cross-linking occurred, and that glass addition did slightly alter bonding environments. Cell viability analysis suggested that extracts of the glass and composites with the largest Ga-content significantly decreased MG-63 osteosarcoma viability after 30days. This study successfully characterized this composite series, and demonstrated their potential for anti-cancerous applications.

Topics: Antineoplastic Agents; Biocompatible Materials; Bone Neoplasms; Carboxymethylcellulose Sodium; Cell Line, Tumor; Cell Survival; Dextrans; Gallium; Glass; Humans; Hydrogels; Osteosarcoma

Poly I:C/poly-L-lysine (poly ICL) was effective in preventing or delaying the development of osteogenic sarcoma (OGS) in mice. C57BL/6J mice were inoculated subcutaneously with 5 X 10(4) OGS cells and treatment was evaluated by palpable tumor development and subsequent day of death. A significant antitumor effect resulted from injection of 150 microgram of poly ICL into the tumor site starting immediately after tumor implant and followed by four subsequent treatments. Seventy percent of treated animals remained tumor free at 50 days, a time at which 70% of placebo treated animals had died as a result of tumor development. A similar treatment regimen of mice inoculated with 2 X 10(5) OGS cells resulted in a significant delay of time to tumor and subsequent day of death. Treatments with poly ICL were ineffective if they were initiated after development of palpable tumor or if they were administered at a nontumorous site on the animal. These findings indicate that the optimal therapy resulted from repeated intratumor treatment prior to development of extensive tumor burden.

Topics: Animals; Antineoplastic Agents; Carboxymethylcellulose Sodium; Cell Transformation, Neoplastic; Interferon Inducers; Methylcellulose; Mice; Mice, Inbred C57BL; Osteosarcoma; Peptides; Poly I-C; Polylysine; Sarcoma, Experimental; Time Factors