The TGF-b/Smad pathway induces breast cancer cell invasion through the up-regulation of matrix metalloproteinase 2 and 9 in a spheroid invasion model system
- نوع فایل : کتاب
- زبان : انگلیسی
- مؤلف : Eliza Wiercinska Hildegonda P. H. Naber Evangelia Pardali Gabri van der Pluijm Hans van Dam Peter ten Dijke
- چاپ و سال / کشور: 2010
Description
Transforming growth factor-b (TGF-b) has opposing roles in breast cancer progression by acting as a tumor suppressor in the initial phase, but stimulating invasion and metastasis at later stages. In contrast to the mechanisms by which TGF-b induces growth arrest, the pathways that mediate tumor invasion are not well understood. Here, we describe a TGF-b-dependent invasion assay system consisting of spheroids of MCF10A1 normal breast epithelial cells (M1) and RAS-transformed (pre-)malignant derivatives (M2 and M4) embedded in collagen gels. Both basal and TGF-b-induced invasion of these cell lines was found to correlate with their tumorigenic potential; M4 showing the most aggressive behavior and M1 showing the least. Basal invasion was strongly inhibited by the TGF-b receptor kinase inhibitor SB- 431542, indicating the involvement of autocrine TGF-b or TGF-b-like activity. TGF-b-induced invasion in premalignant M2 and highly malignant M4 cells was also inhibited upon specific knockdown of Smad3 or Smad4. Interestingly, both a broad spectrum matrix metalloproteinase (MMP) inhibitor and a selective MMP2 and MMP9 inhibitor mitigated TGF-b-induced invasion of M4 cells, while leaving basal invasion intact. In line with this, TGF-b was found to strongly induce MMP2 and MMP9 expression in a Smad3- and Smad4-dependent manner. This collagen-embedded spheroid system therefore offers a valuable screening model for TGF-b/Smad- and MMP2- and MMP9-dependent breast cancer invasion.
Breast Cancer Res Treat (2011) 128:657–666 Received: 29 May 2010 / Accepted: 20 August 2010 / Published online: 5 September 2010 Springer Science+Business Media, LLC. 2010
