Binding of serum ferritin to concanavalin A in patients with malignancy

The percentage non-glycosylated, tissue type ferritin was measured in the serum of 30 cancer patients and 11 normal subjects, as well as in 10 tumour cytosols. As expected, in normal subjects the larger part of serum ferritin corresponded to glycosylated ferritin, and in tumour cytosols the larger part corresponded to non-glycosylated ferritin (tissue ferritin). In all but one cancer patients a significant part of the protein did not bind to Con A, thus behaving as tissue ferritin. The findings obtained suggest release of tissue type, non-glycosylated, ferritin by damaged cells or through abnormal secretion. This relative increase of the non-glycosylated ferritin fraction appears to be very frequently present in cancer, although not specific for it. Assaying for Con A binding may prove to be valuable in the study of malignant disease, and therefore deserves further investigation.