FAK-Src-paxillin system expression and disease outcome in human neuroblastoma

Background: Neuroblastoma (NB) often presents with metastatic disease and poor survival. The need for new prognostic markers remains invaluable. The FAK-Src-Paxillin protein system is associated with aggressive phenotype in adult malignancies but is largely unexplored in pediatric NB. Objective: To assess FAK-Src-Paxillin protein expression in human NB cell lines and clinical cytology material and to delineate its association with survival. Design/Methods: Western blot and immunohistochemistry were applied for FAK-Src-Paxillin expression in NB cell lines and 23 human cytology specimens, respectively. Protein expression in human clinical samples was correlated with clinicopathological parameters, MYCN amplification and survival. Results: FAK, Src and Paxillin proteins are expressed in human NB cells lines, and can be detected in clinical cytology specimens from NB patients, (59%, 32% and 33% respectively). Simultaneous FAK-Src-Paxillin expression was noted in 30% of NB patients. Children with concomitant positivity FAK, Src, and Paxillin tumors, as well as MYCN amplification, had increased mortality compared to those without. Conclusions: FAK-Src-Paxillin system is a marker of unfavorable prognosis for human NB patients but also a promising therapeutic target.