The decrease of the relative abundance of high mannose structures in NB may be caused by the decreased level of the proteins rich in high mannose structures such as alpha-2-macroglobulin, apolipoprotein B-100, immunoglobulin D, immunoglobulin E and immunoglobulin M (36) or the improvement of the synthesis efficiency of complex type glycans. The gene discussed is APOB; the disease is neuroblastoma.