CO2 Pneumoperitoneum Effects on Molecular Markers of Tumor Invasiveness in SH-SY5Y Neuroblastoma Cells.

<bold>Introduction: </bold> CO2 pneumoperitoneum can influence the biological behavior of neuroblastoma (NB). Angiogenesis and genetic features are responsible for malignant phenotype of this tumor. We examined the CO2 effects on N-Myc, vascular endothelial growth factor (VEGF), and matrix metalloproteinase-2 (MMP-2) expression as critical biomarkers of tumor invasiveness, in NB cells without N-Myc amplification.<bold>Materials and Methods: </bold> SH-SY5Y cells were exposed to CO2 (100%) at 15 mm Hg pressure for 4 hours and then moved to normal condition for 24 hours. Control cells were incubated with 5% CO2 for the same time. In control and CO2-exposed cells, the messenger ribonucleic acid (mRNA) levels of hypoxia-inducible factor (HIF)-1α, HIF-2α, VEGF-A, and MMP-2 were quantified by real-time polymerase chain reaction. N-Myc expression was evaluated by Western blot analysis.<bold>Results: </bold> The exposure to 15 mm Hg CO2 (100%) for 4 hours induced an increase in HIF-1α, but not in HIF-2α, mRNA levels. No differences were observed in N-Myc expression between exposed and control cells at each incubation time. Similarly, no significant differences were found for VEGF-A and MMP-2 transcript levels. In CO2 exposed cells, we observed only a slight increase in both VEGF-A and MMP-2 mRNA levels after 4 and 24 hours in comparison to controls.<bold>Conclusion: </bold> In our study, the hypoxic environment induced by CO2 exposure does not affect the expression of critical biomarkers of NB aggressiveness, such as N-Myc, VEGF, and MMP-2, in human SH-SY5Y NB cells without N-Myc amplification. These data suggest that CO2 pneumoperitoneum might not adversely impact NB cell invasiveness; however, it is necessary to evaluate these effects in others in vitro and in vivo models. [ABSTRACT FROM AUTHOR]