Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) acute promyelocytic leukemia ?
    ### Response:
    Acute promyelocytic leukemia is a form of acute myeloid leukemia, a cancer of the blood-forming tissue (bone marrow). In normal bone marrow, hematopoietic stem cells produce red blood cells (erythrocytes) that carry oxygen, white blood cells (leukocytes) that protect the body from infection, and platelets (thrombocytes) that are involved in blood clotting.
    