ABSTRACT
Cancer cells possess unique characteristics such as invasiveness, the ability to undergo epithelial-mesenchymal transition, and an inherent stemness. Cell morphology is altered during these processes and this is highly dependent on actin cytoskeleton remodeling. Regulation of the actin cytoskeleton is, therefore, important for determination of cell fate. Mutations within the TP53 (tumor suppressor p53) gene leading to loss or gain of function (GOF) of the protein are often observed in aggressive cancer cells. Here, we highlight the roles of p53 and its GOF mutants in cancer cell invasion from the perspective of the actin cytoskeleton; in particular its reorganization and regulation by cell adhesion molecules such as integrins and cadherins. We emphasize the multiple functions of p53 in the regulation of actin cytoskeleton remodeling in response to the extracellular microenvironment, and oncogene activation. Such an approach provides a new perspective in the consideration of novel targets for anti-cancer therapy.
Subject(s)
Cytoskeleton/metabolism , Neoplasms/pathology , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , Actin Cytoskeleton/metabolism , Actin Cytoskeleton/pathology , Animals , Cadherins/metabolism , Cell Adhesion Molecules/metabolism , Cell Movement , Humans , Integrins/metabolism , Mutation , Neoplasms/genetics , Neoplasms/metabolism , rho GTP-Binding Proteins/metabolismABSTRACT
p53 (aka TP53) is a powerful tumor suppressor, and oncogenic transformation is induced when the ability of p53 to suppress tumorigenesis is compromised. p53 not only prevents tumorigenesis, but also tumor progression, that is, local invasion and distant metastasis. Recently, we showed that cytoplasmic p53 prevents RAS-driven invasion via alteration of actin cytoskeleton remodeling. This follows modulation of mitochondrial integrity. The transcriptional activity of p53 has been restored using small molecules; however, their success as cancer therapies is largely dependent on the status of downstream targets of p53. It is therefore important to elucidate the role of these downstream targets in p53 regulated tumor progression. With the recently described mechanism of tumor suppression highlighting a role of p53's downstream targets in the regulation of actin cytoskeleton dynamics and lamellipodia formation, we suggest that potential therapeutic targets may be revealed within this mechanism that can be exploited in anticancer therapy.
