Evaluation of SYK protein expression in treated versus untreated retinoblastoma

Introduction Retinoblastoma is the most common intraocular malignancy in infants and children younger than 5 years. If untreated, retinoblastoma can metastasize and becomes fatal. Treatment mainly constitutes chemotherapy or enucleation in advanced cases. RB1 inactivation and epigenetic mutations play different roles in retinoblastoma tumorigenesis . Spleen tyrosine kinase ( SYK ) is a proto-oncogene that was found to be highly expressed in retinoblastoma. Aim We studied SYK expression in retinoblastoma in relation to histopathologic high-risk factors (HRF) while exploring the possible effects of chemotherapy on SYK expression. Material and methods Immunohistochemical staining of sections of paraffin-embedded retinoblastoma tissue was carried out. Detailed study of histopathologic HRF in relation to SYK expression and difference in SYK expression between treated and untreated cases were statistically analyzed. Results Cytoplasmic expression of SYK was detected in all studied cases. No statistical relation between SYK expression and any of the histopathologic HRF (degree of differentiation, nerve invasion, choroidal invasion, and necrosis) was detected. Further, there was no statistically significant difference in SYK expression between treated and untreated cases. Conclusion Expression of SYK in all retinoblastoma cases makes it a promising target for therapy. SYK expression was not correlated with any pathologic HRF. Neoadjuvant chemotherapy did not affect SYK expression.