PO-12 - The key role of talin-1 in cancer cell extravasation dissected through human vascularized 3D microfluidic model. Issue 140 (April 2016)

• Record Type: Journal Article
• Authors: Gilardi, M.; Bersini, S.; Calleja, A. Boussomier; Kamm, R.D.; Vanoni, M.; Moretti, M.
• Is Part Of: Thrombosis research. Issue 140(2016)Supplement 1
• Page Start: S180
• Page End: S181
• Publication Date: 2016-04
• Subjects: Thrombosis -- Periodicals; 616.135
• DOI: 10.1016/S0049-3848(16)30145-1
• Languages: English
• ISSNs: 0049-3848

Abstract

Abstract : Introduction: Metastases are responsible for more than 90% of cancer related mortality. The hematogenous metastatic invasion is a complex process in which the endothelium plays a key role. Extravasation is a dynamic process involving remodeling and change in cell shape and in cytoskeleton whereby a series of strongly dependent interactions between CTCs and endothelium occurs [1]. Talins are proteins regulating focal adhesions and cytoskeleton remodeling. Talin-1 seems to be involved in the aggressiveness, motility, survival and invadopodia formation of cancer cells throughout the entire metastatic cascade [2], being up-regulated in breast cancer cells and mutated in sarcomas. Understand the implication of talin-1 in extravasation could facilitate the design of new therapies and finally fight cancer. Aim: We hypothesized that Talin-1 could be specifically involved in extravasation driving each of its steps. Materials and Methods: We developed a human 3D microfluidic model that enables the study of human cancer cell extravasation within a perfusable human microvascularized organ specific environment[3]. For the study of extravasation we applied microfluidic approach through the development of a microfluidic device in which endothelial cells and fibroblasts generated a 3D human functional vascular networks. Microvessel characterization was performed with immunofluorescence and permeability assays. We knocked-down talin-1 in triple negative breast cancer cell line MDA-MB231 and metastatic fibro-sarcoma cell line HT1080 with SiRNA and verified by Western-blot. Cancer cells were then perfused in the vessels and extravasation monitored through confocal imaging. Results: We developed a human vascularized 3D microfluidic device with human perfusable capillary-like structures embedded in fibrin matrix, characterized by mature endothelium markers and physiological permeability (1.5 ± 0.76) × 10 − 6 cm/s. We focused on the role of Talin-1 in adhesion to endothelium, trans-endothelial migration (TEM) and early invasion. Adhesion to the endothelium, TEM and migration within the ECM were monitored through confocal analyses. We demonstrated that Talin-1 KD significantly reduced the adhesion efficiency and TEM in both cell lines. Early invasion was also strongly and statistically reduced by the SiRNA treatment in both cell lines. Conclusions: We proved Talin-1 function in driving the extravasation mechanism in a human 3D vascularized environment. We demonstrated that Talin-1 is involved in each part of extravasation significantly affecting adhesion, TEM and the invasion stages. Targeting this protein could thus be an effective strategy to block metastasis.