Immunohistochemical Detection of the Presence of Vitamin D Receptor in Childhood Solid Tumors

SIMPLE SUMMARY: Childhood cancer cannot generally be prevented or identified through screening. The disease is often diagnosed at advanced stages, and this obviously affects patient outcomes negatively. There is an urgent need for the identification of prognostic and therapeutic biomarkers. In this study, lower vitamin D receptor (VDR) expression was associated with a worse prognosis in various childhood cancer patients (significant correlation, p = 0.0061). The identification of VDR status in various childhood cancers has highlighted potential patient populations that could benefit from the newly identified biomarker. Knowledge of the VDR status in childhood solid tumors provides clinicians with a valuable biomarker and based on this, additional therapy (vitamin D and analogs) to use alongside conventional first-line oncotherapy. ABSTRACT: Background: Our previous work has shown a correlation between lower vitamin D levels in children with cancer and adverse prognosis. It suggests that supplying vitamin D is reasonable. VDR expression in childhood solid tumors has been linked to tumor characteristics and patient survival in only a few studies. Methods: For this study, 177 children with solid tumors were selected whose biopsies and tumor tissue formalin-fixed, paraffin-embedded tissue blocks were available for immunohistochemical analysis at Semmelweis University, Budapest (Hungary). Results: We found that non-significant VDR expression was associated with a significantly less favorable prognosis (p = 0.0061) in the examined childhood solid tumors. There was a clinically significant association; non-significant VDR expression had more than 14-fold odds of an unfavorable prognosis (OR = 14.74). The rate of VDR expression differed significantly between tumor types (p < 0.0001). Conclusion: In conclusion, VDR expression measured by IHC staining is inversely associated with aggressive characteristics in different childhood cancers. The downregulation of VDR expression in more aggressive childhood cancers suggests that functional vitamin D activity may slow or block cancer progression.