Three-dimensional culture regulates Raf-1 expression to modulate fibronectin matrix assembly.

ABSTRACT: Oncogenic transformation has been associated with decreased fibronectin (FN) matrix assembly. For example, both the HT-1080 fibrosarcoma and MAT-LyLu cell lines fail to assemble a FN matrix when grown in monolayer culture (2-dimensional [2D] system). In this study, we show that these cells regain the ability to assemble a FN matrix when they are grown as aggregates (3-dimensional [3D] system). FN matrix assembly in 3D correlates with decreased Raf-1 protein expression compared with cells grown in monolayer culture. This effect is associated with reduced Raf-1 mRNA levels as determined by quantitative RT-PCR and not proteasome-mediated degradation of endogenous Raf-1. Interestingly, transient expression of a Raf-1 promoter-reporter construct demonstrates increased Raf-1 promoter activity in

SUBMITTER: Winters BS 

PROVIDER: S-EPMC1525224 | biostudies-literature | 2006 Aug

REPOSITORIES: biostudies-literature