Salivary gland extract from Ornithodoros brasiliensis disrupts adhesion-dependent behavior in neuroblastoma cells

Tick salivary secretions are a rich source of bioactive molecules capable of modulating host physiological processes, with emerging relevance in cancer biology. Here, we investigated the effects of a crude salivary gland extract (SGE) from Ornithodoros brasiliensis on neuroblastoma cells. SGE reduced SH-SY5Y cell viability in a concentration-dependent manner, with limited effects on fibroblasts. Morphological analysis revealed early cell rounding and reduced spreading, accompanied by cytoskeletal alterations, including decreased actin stress fibers and reduced cell area. Functional assays showed impaired cell adhesion and re-adhesion capacity, with effects persisting after extract removal. Consistently, migration and clonogenic potential were reduced. SGE induced a modest increase in apoptosis and accumulation of cells in the Sub-G1 phase, without changes in mitochondrial membrane potential, indicating that mitochondrial dysfunction is unlikely to account for the observed apoptotic response. In addition, SGE modulated neuronal differentiation markers, including reduced nestin and doublecortin expression, with a profile partially overlapping that observed with all-trans retinoic acid. Overall, these findings identify a phenotypic response characterized by alterations in adhesion-dependent cellular processes in neuroblastoma cells, accompanied by reduced viability and clonogenic capacity. This study provides an initial functional characterization of the biological activity of O. brasiliensis salivary gland extract in a neuroblastoma model and establishes a framework for future studies aimed at identifying the bioactive molecules responsible for these effects.