Autophagy is Required to Regulate Mitochondria Renewal, Cell Attachment, and All-trans–Retinoic Acid–Induced Differentiation in NB4 Acute Promyelocytic Leukemia Cells

All-trans-retinoic acid (ATRA) is a potent inducer of cellular differentiation, growth arrest, and apoptosis as well as a front-line therapy for acute promyelocytic leukemia (APL). The present study provides evidence that induction of autophagy is required for ATRA to induce differentiation of APL (NB4) cells into granulocytes. ATRA treatment causes ~12-fold increase in the number of acidic vesicular organelles and induces marked up-regulation...