[Expression of modified nucleoside, 1-methyladenosine in intraocular tumors and the retinas]

1-methyladenosine is one of the modified nucleosides, the levels of which are elevated in urine of patients with malignant tumors. We report herein immunohistological expression of 1-methyl-adenosine in tumor cells and retinas. Eight retinoblastomas, 4 malignant melanomas, two metastatic choroidal tumors, 3 retinal dysplasias, one intraocular hemorrhage and 5 normal eye retinas in human were examined. In addition, 8 experimental rabbit choroidal tumor XV2s, and 5 normal rabbit retinas were examined. 1-Methyladenosine was expressed in almost all malignant tumors and retinas with these tumors, while there was little expression in benign tumor cells, retinas with benign tumor and retinas in normal eyes. Results in rabbits were almost the same as in humans. Examination of expression of 1-methyladenosine is expected to be useful for the histological diagnosis of intraocular tumors.