title: A cell-based high-content screening assay reveals activators and inhibitors of cancer cell invasion.
abstract: Acquisition of invasive cell behavior underlies tumor progression and metastasis. To further define the molecular mechanisms underlying invasive behavior, we developed a high-throughput screening strategy to quantitate invadopodia, which are actin-rich membrane protrusions of cancer cells that contribute to tissue invasion and matrix remodeling. We tested the LOPAC 1280 collection of pharmacologically active agents in a high-content, image-based assay and identified compounds that inhibited invadopodium formation without overt toxicity, as well as compounds that increased invadopodia number. The chemotherapeutic agent paclitaxel increased both the number of invadopodia and the invasive behavior of various human cancer cell lines, effects that have potential clinical implications for its use before surgical removal of a primary tumor (neoadjuvant therapy) or in patients with chemoresistant tumors. Several compounds that inhibited invasion have been characterized as cyclin-dependent kinase (Cdk) inhibitors, and loss-of-function experiments determined that Cdk5 was the relevant target. We further determined that Cdk5 promoted both invadopodium formation and cancer cell invasion by phosphorylating and thus decreasing the abundance of the actin regulatory protein caldesmon.
authors.affiliation: Sanford-Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA.
authors.forename: Manuela
authors.initials: M
authors.lastname: Quintavalle
authors.forename: Leonardo
authors.initials: L
authors.lastname: Elia
authors.forename: Jeffrey H
authors.initials: JH
authors.lastname: Price
authors.forename: Susanne
authors.initials: S
authors.lastname: Heynen-Genel
authors.forename: Sara A
authors.initials: SA
authors.lastname: Courtneidge
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D002148:Calmodulin-Binding Proteins / Q000378:metabolism*; D045744:Cell Line, Tumor; D022081:Cell Surface Extensions / Q000187:drug effects* / Q000378:metabolism*; D051360:Cyclin-Dependent Kinase 5 / Q000378:metabolism*; D050756:Cyclin-Dependent Kinase Inhibitor Proteins / Q000494:pharmacology*; D017931:DNA Primers / Q000235:genetics; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D006801:Humans; D051379:Mice; D041681:NIH 3T3 Cells; D009361:Neoplasm Invasiveness / Q000503:physiopathology*; D017239:Paclitaxel / Q000494:pharmacology; D034622:RNA Interference; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D000970:Antineoplastic Agents; D002148:Calmodulin-Binding Proteins; D050756:Cyclin-Dependent Kinase Inhibitor Proteins; D017931:DNA Primers; D051360:Cyclin-Dependent Kinase 5; D017239:Paclitaxel