Serum transferrin receptors were measured by a sandwich radioimmunoassay procedure in patients with iron deficiency anemia, autoimmune hemolytic anemia and aplastic anemia. The mean circulating transferrin receptor concentration of normal subjects and patients with iron deficiency anemia, autoimmune hemolytic anemia and aplastic anemia are 253 +/- 82 ng/mL, 730 +/- 391 ng/mL, 1,426 +/- 1,079 ng/mL, and 182 +/- 39 ng/mL, respectively. The values for those with iron deficiency anemia and autoimmune hemolytic anemia were significantly higher than that of normal controls and the values for those with aplastic anemia were lower than that of normal controls. After iron supplementation in iron deficiency anemia, the serum transferrin receptor values increased twofold over those of pretreatment values. This increase parallels an increase in peripheral reticulocytes. Therefore, the number of circulating transferrin receptors in anemic patients may reflect the level of bone marrow erythropoiesis and is a potentially useful new index for red cell production.

In chronic inflammation it is reported that serum iron is depleted and hepatic iron is increased because of reticuloendothelial system iron blockade. However, recent studies indicate that hepatic parenchymal cells increase the uptake of transferrin-bound iron after in vivo stimulation with bacterial lipopolysaccharide, suggesting that endotoxemia itself or lipopolysaccharide-induced production of inflammation-related cytokines may also be responsible for this phenomenon. In this study the actions of inflammation-related cytokines on the synthesis of iron-binding proteins (transferrin and ferritin) and transferrin receptor and the uptake of transferrin-bound iron were investigated in a human hepatoblastoma cell line, HepG2, which is the most commonly used cell line for examining the regulation of hepatic protein synthesis by cytokines. The cells were exposed to interleukin-1 beta, interleukin-6 or tumor necrosis factor-alpha separately for 24 hr. In each cytokine treatment group, the level of transferrin, which is secreted into the conditioned medium, was found to be decreased compared with that of untreated cells. On the other hand, the biosynthesis of ferritin was markedly elevated after the same treatment. This increase in ferritin by cytokine treatment was diminished when deferoxamine was used concomitantly to deplete intracellular chelatable iron. After stimulation with interleukin-1 beta, interleukin-6 or tumor necrosis factor-alpha, 59Fe-labeled transferrin uptake into the cells was increased by 36%, 48%, or 18%, respectively, and this uptake was inhibited by the addition of excess unlabeled transferrin. A binding study with 125I-labeled diferric transferrin revealed that the three cytokines increased the number of transferrin receptors on the cell surface by 1.15-fold to 1.35-fold.(ABSTRACT TRUNCATED AT 250 WORDS)

Purpose: On the basis of the results of our preliminary trial suggesting that aberrant crypt foci (ACF) could be eradicated by short-term administration of sulindac, in the present study, we explored the feasibility of using ACF as surrogate markers for chemoprevention of colorectal cancer.Experimental design: Randomly assigned to sulindac (300 mg daily), etodolac (400 mg daily), and placebo groups were 189 subjects without polyps or who had undergone polypectomy. Drugs were administered for 2 months. ACF in the rectal region were counted by magnifying endoscopy. Occurrence of polyps was evaluated at 12 months. A planned interim analysis was conducted.Results: ACF number at 2 months was significantly suppressed in the sulindac group (P ¼ 0.0075), but not in the etodolac group (P ¼ 0.73). In the sulindac group, the numbers of adenomas plus hyperplastic polyps (total polyps) and adenomas at 12 months were significantly (P ¼ 0.02) and marginally (P ¼ 0.064) lower, respectively, in comparison with the placebo group; no such difference was observed in the etodolac group. In analysis of only polypectomized subjects, the numbers of total polyps and adenomas in the sulindac group were even more markedly lower, with P values of 0.014 and 0.034, respectively. A similar tendency was confirmed by analyses of the incidence of polyps at 12 months. Suppression rates of total polyps and adenomas in ACF responders to sulindac were significantly greater than in nonresponders. In all groups, compliance was more than 90% and no intolerable adverse effects were observed.Conclusions: ACF may be useful as surrogate lesions for chemoprevention of colorectal cancer. Clin Cancer Res; 17(11); 3803-11. Ó2011 AACR.