RB1 and neoplasm: The tumor suppressor pathways (p53, retinoblastoma (Rb), and phosphatase and tensin homolog (PTEN)) and the proto-oncogene/oncogene pathways (Phosphoinositide 3-kinase/Akt (PI3K/AKT), RAS/RAF, Myc, and BCL-2) will be highlighted due to their broad implications in multiple tumor types [5,6].