Mechanisms of cyto-toxicity of chemical agents to giant cell tumor: an in-vitro study

Background:Various chemicals have been used as an adjuvant treatment for
giant cell tumor (GCT). However, the comparative effect of these chemicals
remains unclear. Methods:Cell line from GCT patients characterized by gene
markers Nanog and Oct ¾ expression with RT-PCR was obtained. GCT cells
were treated with H2O2 1%, 3%, 5% and ethanol 75%, 85%, 95% for 10 minutes
and in vitro doses of H2O2 (0.003%, 0.005%, 0.01%, 0.03 %, 0.1%, 0.3%) for
5 minutes and were incubated for 24 hours. Cell morphology, cell viability
and cell toxicity were assessed. Results:Viability of GCT cells decreased
significantly after exposure to the dose of H2O2 1% (p = 0.046), H2O2 3%
(p = 0.043), and H2O2 5% (p = 0.043). There was no significant difference
for cell viability between 1%, 3% and 5% H2O2 concentrations. While in in
vitro doses, 0.3% H2O2 concentration has the best effectivity in
sterilizing GCT. There was a phenomenon of cell fixation after exposure of
GCT cells to ethanol. RT-PCR demonstrated a decrease in the expression of
Oct 3/4 and Nanog genes along with an increase in the concentration of
H2O2. Flowcytometry using Annexin V showed cell death due to necrosis,
with the highest concentration amounted to 0.3% Conclusion: Giving local
chemical adjuvants of H2O2 concentrations of 1%, 3%, and 5% in vitro had
the same effectiveness in killing GCT cells. While the concentration of
0.3% H2O2 for 5 minutes is the optimal therapy in GCT sterilization in
vitro with necrosis cell death mechanism.