AGING RETINAL NEURONS IN RETINOBLASTOMA

Cells of non-hereditary retinblastoma in the enucleated eye of a 9-year-old boy were studied using classical histological and immunohistochemical methods. It has been established that disturbances in retinal morphogenesis can be associated with a stop in development at the stage of formation of retinal layers. The inner wall of the eyecup after the eviction of the neuroglia retained proliferative activity in the cells of the outer retinal layer, which lost the ability to differentiate over a larger extent of the retina and migrate to the inner layers. Cells that have differentiated according to the program of neuronal development are located among malignant cells and are characterized by signs of atypical aging with granules of black-brown pigment in the cytoplasm. It has been established that in the lack of angiogenesis these cells in the inner layers of the retina have secretory activity and are immunohistochemically phenotyped as VEGF-positive cells. This indicates cellular and tissue adaptation to malignancy at the terminal stage of retinoblastoma, which grows into the optic nerve and metastasizes to the brain. VEGF-positive cells can serve as one of the key targets in solving the problem of conservative treatment of retinoblastoma diagnosed in the late stages of the disease.