Abstract 3978: Lipid tethering to enable real-time imaging of breast tumor cell cytoskeletal dynamics and rapid drug testing in free-floating metastatic microenvironments

Abstract

Abstract Free-floating tumor cells located in the peripheral circulation of cancer patients, known as circulating tumor cells (CTCs), play an important role in cancer and have become key targets for studying metastasis. The presence of CTCs in the bloodstream or lymphatics correlates with decreased cancer patient survival and provides a minimally invasive method to study disease progression and treatment response. Understanding the molecular characteristics and functional properties of CTCs have been impeded by the challenges of imaging CTCs under conditions that model the free-floating microenvironments of the circulation. Upon extracellular-matrix (ECM) detachment, breast tumor cells form tubulin-based protrusions known as microtentacles (McTNs) that play a role in the aggregation and re-attachment of tumor cells to increase their metastatic efficiency. In this study, we have designed a strategy to spatially immobilize ECM-detached tumor cells within a microfluidic device while maintaining their free-floating character. We use cytophobic polyelectrolyte multilayers deposited on microfluidic substrates to prevent tumor cell adhesion and the addition of lipid moieties to tether tumor cells to these surfaces through interactions with the cell membrane. This approach enables high-resolution time-lapse microscopy of McTNs on viable free-floating tumor cells and real-time analysis of dynamic cellular features. In addition, tethering makes it now possible to rapidly measure drug responses of tumor cells in free-floating microenvironments to select effective therapies and avoid drugs that could inadvertently increase metastasis. The ability to image tumor cells in the absence of ECM attachment can immensely enhance our understanding of CTCs under conditions that better recapitulate the free-floating microenvironments that tumor cells encounter during metastasis. Citation Format: Kristi Riti Chakrabarti, James Andorko, Rebecca Whipple, Peipei Zhang, Elisabeth Sooklal, Christopher Jewell, Stuart Martin. Lipid tethering to enable real-time imaging of breast tumor cell cytoskeletal dynamics and rapid drug testing in free-floating metastatic microenvironments. [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 3978.