Proteases and Cancer

Tania Fontanil, Yamina Mohamedi, Santiago Cal, Álvaro J. Obaya

Proteases play crucial roles in all steps of tumor progression including cancer cell migration. In fact, uncontrolled proteolytic activity could lead to the degradation of different components of the extracellular matrix which facilitates dissemination of tumor cells. However, numerous studies have revealed that proteases may also exert tumor-protective actions which could impede progression of malignant cells. Consequently, it is crucial to distinguish those situations in which proteases promote tumor growth from those in which exhibit tumor-suppressive effects. In this regard, analysis of the influence of a particular protease on the capacity of a cell line to migrate can be employed as an approach to better understand its involvement in tumorigenesis. Different experimental designs have been developed to investigate cell migration. Herein, we describe a barrier assay to monitor cell migration, which overcomes some disadvantages of traditional methods such as the Boyden chamber or the wound healing assays. The version of the barrier assay explained in this chapter allows to examine cell migration through the analysis of the closure of a premade 500 μm wound. This method also facilitates comparison between two different situations in a given cell line (i.e., gene up- or downregulation) in the same assay and under the same conditions. Additionally, migration can be monitored and measured using a time lapse microscope which facilitates further analysis through different softwares.