 Subsequent evaluation, including the karyotype that showed absence of the defining t(15;17) translocation, concluded that HL-60 cells are from a case of AML FAB-M2 (now referred to as AML with maturation (WHO)).Proliferation of HL-60 cells occurs through the transferrin and insulin receptors, which are expressed on cell surface.The requirement for insulin and transferrin is absolute, as HL-60 proliferation immediately ceases if either of these compounds is removed from the serum-free culture media.