Fiche publication
Date publication
septembre 2013
Auteurs
Membres identifiés du Cancéropôle Est :
Dr DULUC Isabelle
,
Dr FREUND Jean-Noël
,
Pr LEHN Jean-Marie
,
Dr MARTIN Etienne
,
Dr PENCREACH Erwan
Tous les auteurs :
Derbal-Wolfrom L, Pencreach E, Saandi T, Aprahamian M, Martin E, Greferath R, Tufa E, Choquet P, Lehn JM, Nicolau C, Duluc I, Freund JN
Lien Pubmed
Résumé
Preventing tumor neovascularisation is one of the strategies recently developed to limit the dissemination of cancer cells and apparition of metastases. Although these approaches could improve the existing treatments, a number of unexpected negative effects have been reported, mainly linked to the hypoxic condition and the subsequent induction of the pro-oncogenic hypoxia inducible factor(s) resulting from cancer cells' oxygen starvation. Here, we checked in vivo on colon cancer cells an alternative approach. It is based on treatment with myo-inositol trispyrophosphate (ITPP), a molecule that leads to increased oxygenation of tumors. We provide evidence that ITPP increases the survival of mice in a model of carcinomatosis of human colon cancer cells implanted into the peritoneal cavity. ITPP also reduced the growth of subcutaneous colon cancer cells xenografted in nu/nu mice. In the subcutaneous tumors, ITPP stimulated the expression of the homeobox gene Cdx2 that is crucial for intestinal differentiation and that also has an anti-tumoral function. On this basis, human colon cancer cells were cultured in vitro in hypoxic conditions. Hypoxia was shown to decrease the level of Cdx2 protein, mRNA and the activity of the Cdx2 promoter. This decline was unrelated to the activation of HIF1alpha and HIF2alpha by hypoxia. However, it resulted from the activation of a phosphatidylinositol 3-kinases-like mitogen-activated protein kinase pathway, as assessed by the fact that LY294002 and U0126 restored high Cdx2 expression in hypoxia. Corroborating these results, U0126 recapitulated the increase of Cdx2 triggered by ITPP in subcutaneous colon tumor xenografts. The present study provides evidence that a chemical compound that increases oxygen pressure can antagonize the hypoxic setting and reduce the growth of human colon tumors implanted in nu/nu mice.
Référence
Oncogene. 2013 Sep 5;32(36):4313-8
