Neutrophils activated by BJcuL, a C-type lectin isolated from Bothrops jararacussu venom, decrease the invasion potential of neuroblastoma SK-N-SH cells in vitro

ABSTRACT

ABSTRACT Background: Neuroblastoma is a pediatric tumor with a mortality rate of 40% in the most aggressive cases. Tumor microenvironment components as immune cells contribute to the tumor progression; thereby, the modulation of immune cells to a pro-inflammatory and antitumoral profile could potentialize the immunotherapy, a suggested approach for high-risk patients. Preview studies showed the antitumoral potential of BJcuL, a C- type lectin isolated from Bothrops jararacussu venom. It was able to induce immunomodulatory responses, promoting the rolling and adhesion of leukocytes and the activation of neutrophils. Methods: SK-N-SH cells were incubated with conditioned media (CM) obtained during the treatment of neutrophils with BJcuL and fMLP, a bacteria-derived peptide highly effective for activating neutrophil functions. Then we evaluated the effect of the same stimulation on the co-cultivation of neutrophils and SK-N-SH cells. Tumor cells were tested for viability, migration, and invasion potential. Results: In the viability assay, only neutrophils treated with BJcuL (24 h) and cultivated with SK-N-SH were cytotoxic. Migration of tumor cells decreased when incubated directly (p 0.001) or indirectly (p 0.005) with untreated neutrophils. When invasion potential was evaluated, neutrophils incubated with BJcuL reduced the total number of colonies of SK-N-SH cells following co-cultivation for 24 h (p 0.005). Treatment with CM resulted in decreased anchorage-free survival following 24 h of treatment (p 0.001). Conclusion: Data demonstrated that SK-N-SH cells maintain their migratory potential in the face of neutrophil modulation by BJcuL, but their invasive capacity was significantly reduced.