Abstract 5053: Tumor cell clustering - Identification of new regulators

Abstract

Abstract Cancer cell aggregation is a key process involved at different stages of tumor evolution, during primary tumor growth, metastatic cells dissemination and secondary tumor evolution. Thus, understanding principles that govern and modulate the ability of cancer cells to aggregate might pave the way for new therapeutic opportunities. We investigated cancer cell aggregation independently of cell migration or matrix adhesion and demonstrated that the cell-cell adhesion protein E-cadherin and the desmosome proteins DSG2 and DSC2 are both involved this process (Saias, 2015). Strikingly, elevated expression of these proteins in primary tumors has also been reported to be associated with blood detection of clusters of highly metastatic circulating tumor cells and poor prognosis (Aceto, 2014). We also reported that Myosin IIa applies a counter force that slows down aggregation indicating that acto-myosin cytoskeleton tension favors aggregation. To further decipher the regulation of this process, we developed arrays of hydrogel microwells and robust microscopy-based quantification assay to monitor the kinetics of aggregation of tumor cells in the absence of cell - substrate adhesion. We performed a candidate approach and found that several other members of the cadherin superfamily are involved in the aggregation process. We also conducted a small molecule screen to identify other pathways involved in regulating aggregation of tumor cells. We will report unpublished results on the characterization of the molecular bases of aggregation properties in various tumor cell types and on the identification of new regulatory mechanisms that modulate this process. - Saias L, Gomes A, Cazales M, Ducommun B, Lobjois V. Cell-cell adhesion and cytoskeleton tension oppose each other in regulating tumor cell aggregation. Cancer Res. (2015) 75(12); 1-8 - Aceto N, Bardia A, Miyamoto DT, Donaldson MC, Wittner BS, Spencer JA, et al. Circulating tumor cell clusters are oligoclonal precursors of breast cancer metastasis. Cell 2014;158:1110-22. Citation Format: Valérie LOBJOIS, Bernard Ducommun. Tumor cell clustering - Identification of new regulators. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5053.