Degraded iota-carrageenan can induce apoptosis in human osteosarcoma cells via the Wnt/β-catenin signaling pathway

Nutr Cancer. 2013;65(1):126-31. doi: 10.1080/01635581.2013.741753.


Osteosarcoma (OS) is a high-grade malignant bone tumor. Therefore, using both in vitro and in vivo assays, the effects of degraded iota-Carrageenan (ι-CGN) on a human osteosarcoma cell line, HOS, were examined. Degraded ι-CGN was observed to induce apoptosis and G(1) phase arrest in HOS cells. Moreover, degraded ι-CGN suppressed tumor growth in established xenograft tumor models. Accordingly, the survival rate of these mice was significantly higher than that of mice bearing tumors treated with native ι-CGN or PBS. In addition, the formation of intratumoral microvessels was inhibited following treatment with degraded ι-CGN. In Western blot assays, degraded ι-CGN was found to inhibit the Wnt/β-catenin signaling pathway. Overall, these studies demonstrate the antitumor activity of degraded ι-CGN toward the OS cell line, HOS. Moreover, valuable insight into the mechanisms mediated by degraded ι-CGN was obtained, potentially leading to the identification of novel treatments for OS. However, additional studies are needed to confirm these results in other cell types, particularly in human umbilical vein endothelial cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / drug effects*
  • Bone Neoplasms / drug therapy*
  • Bone Neoplasms / metabolism
  • Bone Neoplasms / pathology*
  • Carrageenan / chemistry
  • Carrageenan / pharmacology*
  • Cell Line, Tumor
  • Humans
  • Low Density Lipoprotein Receptor-Related Protein-6 / metabolism
  • Mice
  • Mice, Inbred NOD
  • Osteosarcoma / drug therapy*
  • Osteosarcoma / metabolism
  • Osteosarcoma / pathology*
  • Phosphorylation / drug effects
  • Wnt Signaling Pathway / drug effects
  • Xenograft Model Antitumor Assays


  • LRP6 protein, human
  • Low Density Lipoprotein Receptor-Related Protein-6
  • Carrageenan