A mutually nonexclusive explanation for the differential nucleolin aptamer-conjugated siRNA delivery to cancer cells proposed by Reyes-Reyes et al. is that the uptake of the aptamer cross-linked nucleolin on the cell surface of cancer, but not normal cells, is mediated via macropinocytosis and hence delivery of the complex to the cytoplasm, whereas in non-transformed cells the aptamer is either recycled or transported to the lysosome39. This evidence concerns the gene NUCLEOLIN and cancer.