Multi-sample deformability cytometry of cancer cells

Abstract

There is growing recognition that cell deformability can play an important role in cancer metastasis and diagnostics. Advancement of methods to characterize cell deformability in a high throughput manner and the capacity to process numerous samples can impact cancer-related applications ranging from analysis of patient samples to discovery of anti-cancer compounds to screening of oncogenes. In this study, we report a microfluidic technique called multi-sample deformability cytometry (MS-DC) that allows simultaneous measurement of flow-induced deformation of cells in multiple samples at single-cell resolution using a combination of on-chip reservoirs, distributed pressure control, and data analysis system. Cells are introduced at rates of O(100) cells per second with a data processing speed of 10 min per sample. To validate MS-DC, we tested more than 50 cell-samples that include cancer cell lines with different metastatic potential and cells treated with several cytoskeletal-intervention drugs. Results from MS-DC show that (i) the cell deformability correlates with metastatic potential for both breast and prostate cancer cells but not with their molecular histotype, (ii) the strongly metastatic breast cancer cells have higher deformability than the weakly metastatic ones; however, the strongly metastatic prostate cancer cells have lower deformability than the weakly metastatic counterparts, and (iii) drug-induced disruption of the actin network, microtubule network, and actomyosin contractility increased cancer cell deformability, but stabilization of the cytoskeletal proteins does not alter deformability significantly. Our study demonstrates the capacity of MS-DC to mechanically phenotype tumor cells simultaneously in many samples for cancer research.

Biophysical analysis of fluid shear stress induced cellular deformation in a microfluidic device

“…To further ensure that the fluid shear stresses as calculated were the dominant forces causing cellular deformation, the pressure drop across individual trapped cells was quantified using COMSOL simulations and were found to be approximately 10 and 21 Pa for 5 and 15 dyn/cm 2 , respectively. These magnitudes are fractional when compared to established studies that look at pressure induced cell deformation, which can use pressure gradients in the range of 1500-20 265 Pa. 29,30 B. Increasing fluid shear stress magnitude and duration results in a greater extent of cellular deformation…”

The mechanics of myeloid cells

“…Real‐time deformability cytometry (RT‐DC) as introduced by Otto et al., similarly deforms individual cells by shear stresses and pressure gradients as they flow through a microfluidic channel (Figure 2B) [Otto et al., ]. Multi‐sample deformability cytometry uses a microfluidic chamber resembling that of Otto et al., which allows for analysis of up to 10 clinical samples of cells in suspension within a single experiment [Ahmmed et al., ]. There have been several other, related techniques published in recent years [Rosendahl et al., ; Guck, ].…”

“…Even recent advances with scanning probe AFM require time scales in the milliseconds [Müller and Dufrêne, ]. In contrast, DC measures over 1000 individual cells per second and also allows for analysis of heterogenous samples in suspension, including whole blood [Tse et al., ; Otto et al., ; Ahmmed et al., ]. This suggests opportunities for clinical adaptations [Guck, ].…”

Rationally engineered advances in cancer research

“…They deepen understanding by advanced imaging or by building simple systems to focus on a microenvironment property, such as ECM that is stiffer, 1 more dense, 2 crosslinked, 3 aligned, 1 or less porous 3 . The efforts profiled here investigate or summarize our knowledge of tumors in four ways: (1) some clarify how intratumor or stromal fluid 4,5 or blood flow 6 drives tumor behavior, (2) others develop model in vitro systems to understand 7–10 or measure 11 tumor behavior, (3) still others examine how cancer cells sense changes in their niche 12 and how that drive behaviors, 13,14 and (4) a few are more integrative with computational simulations of complex processes in cancer 15–17 …”