TTR and retinoblastoma: The same analysis also revealed that treated RB eyes, with or without active tumors (Group 1, 2 and 4), showed an upregulation of proteins involved in metabolism, among those identified were mainly oxidoreductases (glutamate–cysteine ligase, transthyretin), transferases (glutathione transferase; glutaredoxin-1), and proteins involved in lipid metabolism (ApolipoproteinA4; ApolipoproteinA1).