The browser you are using is not supported by this website. All versions of Internet Explorer are no longer supported, either by us or Microsoft (read more here: https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Please use a modern browser to fully experience our website, such as the newest versions of Edge, Chrome, Firefox or Safari etc.

Galectin-1-binding glycoforms of haptoglobin with altered intracellular trafficking, and increase in metastatic breast cancer patients.

På svenska

Author

  • Michael Carlsson
  • Cecilia Cederfur
  • Viveka Schaar
  • Crina I A Balog
  • Adriana Lepur
  • Franck Touret
  • Emma Salomonsson
  • André M Deelder
  • Mårten Fernö
  • Håkan Olsson
  • Manfred Wuhrer
  • Hakon Leffler
Show all

Summary, in English

Sera from 25 metastatic breast cancer patients and 25 healthy controls were subjected to affinity chromatography using immobilized galectin-1. Serum from the healthy subjects contained on average 1.2 mg per ml (range 0.7-2.2) galectin-1 binding glycoproteins, whereas serum from the breast cancer patients contained on average 2.2 mg/ml (range 0.8-3.9), with a higher average for large primary tumours. The major bound glycoproteins were α-2-macroglobulin, IgM and haptoglobin. Both the IgM and haptoglobin concentrations were similar in cancer compared to control sera, but the percentage bound to galectin-1 was lower for IgM and higher for haptoglobin: about 50% (range 20-80) in cancer sera and about 30% (range 25-50) in healthy sera. Galectin-1 binding and non-binding fractions were separated by affinity chromatography from pooled haptoglobin from healthy sera. The N-glycans of each fraction were analyzed by mass spectrometry, and the structural differences and galectin-1 mutants were used to identify possible galectin-1 binding sites. Galectin-1 binding and non-binding fractions were also analyzed regarding their haptoglobin function. Both were similar in forming complex with haemoglobin and mediate its uptake into alternatively activated macrophages. However, after uptake there was a dramatic difference in intracellular targeting, with the galectin-1 non-binding fraction going to a LAMP-2 positive compartment (lysosomes), while the galectin-1 binding fraction went to larger galectin-1 positive granules. In conclusion, galectin-1 detects a new type of functional biomarker for cancer: a specific type of glycoform of haptoglobin, and possibly other serum glycoproteins, with a different function after uptake into tissue cells.

Publishing year

2011

Language

English

Publication/Series

PLoS ONE

Volume

6

Issue

10

Document type

Journal article

Publisher

Public Library of Science (PLoS)

Topic

  • Microbiology in the medical area

Status

Published

Research group

  • Neuronano Research Center (NRC)
  • Clinical Microbiology, Malmö

ISBN/ISSN/Other

  • ISSN: 1932-6203