title: The Rac activator Tiam1 and Ras-induced oncogenesis.
abstract: The Tiam1 gene encodes a guanine nucleotide exchange factor (GEF) that specifically activates the Rho-like GTPase Rac. In vitro studies indicate that Tiam1 localizes to adherens junctions and plays a role in the formation and maintenance of cadherin-based cell adhesions, thereby regulating migration of epithelial cells. In vivo studies implicate Tiam1 in various aspects of tumorigenesis. In this chapter, we discuss the use of the DMBA/TPA chemical carcinogenesis protocol in Tiam1-deficient mice to study the role of Tiam1 in Ras-induced skin tumors. This two-stage carcinogenesis protocol allows us to study initiation, promotion, and progression of tumors in a Tiam1-positive and Tiam1-negative background. Moreover, we describe methods to study the role of Tiam1 in susceptibility to apoptosis, cell growth, and Ras transformation by in vivo and in vitro experiments. The latter makes use of tumor cells and primary embryonic fibroblasts and keratinocytes isolated from mice.
authors.affiliation: The Netherlands Cancer Institute, Division of Cell Biology, Amsterdam, The Netherlands.
authors.forename: Kristin
authors.initials: K
authors.lastname: Strumane
authors.forename: Tomasz P
authors.initials: TP
authors.lastname: Rygiel
authors.forename: John G
authors.initials: JG
authors.lastname: Collard
mesh_terms: D015127:9,10-Dimethyl-1,2-benzanthracene; D000818:Animals; D017209:Apoptosis / Q000502:physiology; D002469:Cell Separation; D015536:Down-Regulation; D020662:Guanine Nucleotide Exchange Factors / Q000502:physiology*; D015603:Keratinocytes / Q000166:cytology; D051379:Mice; D018345:Mice, Knockout; D041681:NIH 3T3 Cells; D012878:Skin Neoplasms / Q000209:etiology / Q000473:pathology; D000075684:T-Lymphoma Invasion and Metastasis-inducing Protein 1; D018631:ras Proteins / Q000502:physiology*
chemical_list: D020662:Guanine Nucleotide Exchange Factors; D000075684:T-Lymphoma Invasion and Metastasis-inducing Protein 1; C513260:Tiam1 protein, mouse; D015127:9,10-Dimethyl-1,2-benzanthracene; D018631:ras Proteins