Wheatgerm agglutinin-mediated toxicity in pancreatic cancer cells Academic Article uri icon

Overview

MeSH Major

  • Antineoplastic Agents
  • Cell Survival
  • N-Acetylneuraminic Acid
  • Phytohemagglutinins
  • Wheat Germ Agglutinins

abstract

  • Lectin binding specificities for carbohydrate allow phenotypic and functional characterization of membrane-associated glycoproteins expressed on cancer cells. This analysis examined wheatgerm agglutinin binding to pancreatic cancer cells in vitro and the resulting toxicity. Membrane preparations of nine human pancreatic carcinoma cell lines were studied for lectin binding using wheatgerm agglutinin (WGA), concanavalin A (ConA) and phytohaemagglutinin-L (PHA-L) in a lectin blot analysis. Cell proliferation in vitro was measured by thymidine incorporation in the absence or presence of lectins at various concentrations. Sialic acid binding lectins or succinyl-WGA (succWGA) served as controls. WGA toxicity was tested after swainsonine or neuraminidase pretreatment. Binding and uptake of fluorescein-labelled lectins was studied under fluorescence microscopy. All pancreatic cell lines displayed high WGA membrane binding, primarily to sialic acid residues. Other lectins were bound with weak to moderate intensity only. Lectin toxicity corresponded to membrane binding intensity, and was profound in case of WGA (ID50 at 2.5-5 microg ml(-1)). WGA exposure induced chromatin condensation, nuclear fragmentation and DNA release consistent with apoptosis. Important steps for WGA toxicity included binding to sialic acid on swainsonine-sensitive carbohydrate and lectin internalization. There was rapid cellular uptake and subsequent nuclear relocalization of WGA. In contradistinction to the other lectins studied, WGA proved highly toxic to human pancreatic carcinoma cells in vitro. WGA binding to sialic acid residues of N-linked carbohydrate, cellular uptake and subsequent affinity to N-acetyl glucosamine appear to be necessary steps. Further analysis of this mechanism of profound toxicity may provide insight relevant to the treatment of pancreatic cancer.

publication date

  • August 26, 1999

Research

keywords

  • Academic Article

Identity

Language

  • eng

PubMed Central ID

  • PMC2363124

Digital Object Identifier (DOI)

  • 10.1038/sj.bjc.6690593

PubMed ID

  • 10468292

Additional Document Info

start page

  • 1754

end page

  • 62

volume

  • 80

number

  • 11