In tumour cells, BC200 is primarily localized to the cytoplasm where it has been shown to bind a number of proteins (SRP9/SRP14, PABPC1, eIF4A, FMR1, SYNCRIP, hnRNPA2B1, PCBP1/2 and DHX36); however, a complete analysis of the BC200 ribonucleoprotein (RNP) has yet to be performed (7,9,10,19–24). This evidence concerns the gene BCYRN1 and neoplasm.