CD320 and cancer: Many data suggest an important role for TCII-R in cobalamin uptake in the situation of high cellular anabolism: (i) corticosteroid treatment raises the expression and activity of TCII-R [79], (ii) mitogen stimuli raise the TCII-R expression in lymphocytes [80], (iii) cancer cells have an elevation in cobalamin uptake [4], and (iv) the expression of TCII-R is upregulated in several cancers [81].