Tags

Type your tag names separated by a space and hit enter

Isolation and characterization of a novel vitamin B12-binding protein associated with hepatocellular carcinoma.
J Clin Invest. 1975 Nov; 56(5):1262-70.JCI

Abstract

High levels of a novel vitamin B12-binding protein (hepatoma B12 BP) have been observed recently in plasma obtained from three adolescent patients with hepatocellular carcinoma. This protein has now been isolated in homogeneous form from the plasma and pleural fluid of two of these patients by the use of affinity chromatography with vitamin B12-Sepharose. The hepatoma B12 BP belongs to the R-type group of B12-binding proteins and is essentially indistinguishable from the recently isolated human milk and saliva R-type proteins in terms of: (a) immunologic properties based on immunodiffusion and immunoprecipitation assays; (b) amino acid composition; (c) molecular weight based on amino acid and carbohydrate content; and (d) absorption spectra. Both hepatoma B12 BPs contain more sialic acid and less fucose than the milk and saliva B12 BPs. All four proteins contain similar amounts of galactose, mannose, galactosamine, and glucosamine. Differences in sialic acid content appear to account for the differences in electrophoretic mobility that were observed among the four proteins. Differences in total carbohydrate content appear to account for the differences in apparent molecular weight that were observed with both gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Tumor tissue from one of the patients contained 10 times as much R-type protein as did normal liver tissue from the same patient. This suggests, although it does not prove, that synthesis by the tumor is the cause of the high levels of R-type protein found in the plasma of certain patients with hepatocellular carcinoma. Plasma survival studies performed with rabbits indicate that the hepatoma B12 BP has a prolonged plasma survival and suggests that his parameter is also of importance.

Authors

No affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, U.S. Gov't, P.H.S.

Language

eng

PubMed ID

171283

Citation

Burger, R L., et al. "Isolation and Characterization of a Novel Vitamin B12-binding Protein Associated With Hepatocellular Carcinoma." The Journal of Clinical Investigation, vol. 56, no. 5, 1975, pp. 1262-70.
Burger RL, Waxman S, Gilbert HS, et al. Isolation and characterization of a novel vitamin B12-binding protein associated with hepatocellular carcinoma. J Clin Invest. 1975;56(5):1262-70.
Burger, R. L., Waxman, S., Gilbert, H. S., Mehlman, C. S., & Allen, R. H. (1975). Isolation and characterization of a novel vitamin B12-binding protein associated with hepatocellular carcinoma. The Journal of Clinical Investigation, 56(5), 1262-70.
Burger RL, et al. Isolation and Characterization of a Novel Vitamin B12-binding Protein Associated With Hepatocellular Carcinoma. J Clin Invest. 1975;56(5):1262-70. PubMed PMID: 171283.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Isolation and characterization of a novel vitamin B12-binding protein associated with hepatocellular carcinoma. AU - Burger,R L, AU - Waxman,S, AU - Gilbert,H S, AU - Mehlman,C S, AU - Allen,R H, PY - 1975/11/1/pubmed PY - 1975/11/1/medline PY - 1975/11/1/entrez SP - 1262 EP - 70 JF - The Journal of clinical investigation JO - J Clin Invest VL - 56 IS - 5 N2 - High levels of a novel vitamin B12-binding protein (hepatoma B12 BP) have been observed recently in plasma obtained from three adolescent patients with hepatocellular carcinoma. This protein has now been isolated in homogeneous form from the plasma and pleural fluid of two of these patients by the use of affinity chromatography with vitamin B12-Sepharose. The hepatoma B12 BP belongs to the R-type group of B12-binding proteins and is essentially indistinguishable from the recently isolated human milk and saliva R-type proteins in terms of: (a) immunologic properties based on immunodiffusion and immunoprecipitation assays; (b) amino acid composition; (c) molecular weight based on amino acid and carbohydrate content; and (d) absorption spectra. Both hepatoma B12 BPs contain more sialic acid and less fucose than the milk and saliva B12 BPs. All four proteins contain similar amounts of galactose, mannose, galactosamine, and glucosamine. Differences in sialic acid content appear to account for the differences in electrophoretic mobility that were observed among the four proteins. Differences in total carbohydrate content appear to account for the differences in apparent molecular weight that were observed with both gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Tumor tissue from one of the patients contained 10 times as much R-type protein as did normal liver tissue from the same patient. This suggests, although it does not prove, that synthesis by the tumor is the cause of the high levels of R-type protein found in the plasma of certain patients with hepatocellular carcinoma. Plasma survival studies performed with rabbits indicate that the hepatoma B12 BP has a prolonged plasma survival and suggests that his parameter is also of importance. SN - 0021-9738 UR - https://www.unboundmedicine.com/medline/citation/171283/Isolation_and_characterization_of_a_novel_vitamin_B12_binding_protein_associated_with_hepatocellular_carcinoma_ L2 - https://doi.org/10.1172/JCI108202 DB - PRIME DP - Unbound Medicine ER -