Co-stimulation of human breast cancer cells with transforming growth factor-beta and tenascin-C enhances matrix metalloproteinase-9 expression and cancer cell invasion.

Transforming growth factor-beta (TGF-beta), tenascin-C (TN-C) and matrix metalloproteinases (MMPs) have been demonstrated independently to be associated with disease progression and poor prognosis in patients with breast cancer. The present study explored effects of TGF-beta and TN-C on MMP-9 expression and cancer invasion. An experimental study was designed to analyse MDA-MB-231 breast cancer cells, known for their high invasiveness, after stimulation with TGF-beta1 and/or TN-C.

Involvement of large tenascin-C splice variants in breast cancer progression.

Alternative splicing of fibronectin-like type III (FNIII) repeats of tenascin-C (Tn-C) generates a number of splice variants. The distribution of large variants, typical components of provisional extracellular matrices that are up-regulated during tumor stroma remodeling, was here studied by immunoblotting and immunohistochemistry using a monoclonal antibody against the FNIII B domain (named 4C8MS) in a series of human breast cancers. Large Tn-C variants were found at only low levels in normal breast tissues, but were highly expressed at invading sites of intraductal cancers and in the stroma of invasive ductal cancers, especially at invasion fronts.

Tenascin-C upregulates matrix metalloproteinase-9 in breast cancer cells: direct and synergistic effects with transforming growth factor beta1.

Tenascin-C (TN-C) and matrix metalloproteinases (MMPs) are highly expressed in cancer tissues and probably promote cell migration during cancer progression. TN-C and MMPs are often co-localized in areas of active tissue remodeling in pathologic conditions, suggesting reciprocal regulation. To investigate whether TN-C regulates MMPs expression in cancer cells, we first exposed mammary cancer cells derived from TN-C-deficient mice to TN-C and examined MMPs expression.