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The expression of integrins is decreased in colon cancer cells treated with polysaccharide K

Keiko Aso1, Takanori Goi, Toshiyuki Nakazawa

  • 1First Department of Surgery, University of Fukui, Yoshida-gun, Fukui, Japan.

International Journal of Oncology
|February 22, 2013
PubMed

Insights

Polysaccharide K (PSK) reduces colon cancer cell adhesion to various substrates and vascular endothelial cells. This novel mechanism involves suppressing integrin expression on cancer cell surfaces, potentially improving cancer prognosis.

Area of Science:

  • Immunology
  • Oncology
  • Molecular Biology

Background:

  • Polysaccharide K (PSK) is an immunotherapeutic agent used for malignant tumors.
  • Its precise mechanism of action in colon cancer remains under-investigated.

Purpose of the Study:

  • To elucidate the genes regulated by PSK in colon cancer cells.
  • To understand the specific actions PSK exerts on colon cancer cells.

Main Methods:

  • In vitro exposure of colon cancer cells to PSK.
  • Assessment of morphological and adhesive changes.
  • Analysis of integrin expression (mRNA α and β).
  • Evaluation of cancer cell adhesion to vascular endothelial cells.

Main Results:

  • PSK induced spherical morphology in colon cancer cells.
  • Reduced adhesion to laminin, fibrinogen, collagen IV, collagen I, and fibronectin.
  • Decreased expression of integrin mRNA α and β.
  • Significantly reduced adhesion of PSK-treated cells to vascular endothelial cells.

Conclusions:

  • PSK suppresses integrin expression on colon cancer cell surfaces.
  • PSK reduces the adhesion of colon cancer cells to vascular endothelial cells.
  • These findings reveal a novel mechanism of PSK action in colon cancer.

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