Traversing behavior of tumor cells in three-dimensional platforms with different topography

Abstract

Three-dimensional polydimethylsiloxane platforms were developed to mimic the extracellular matrix with blood vessels by having scaffolds with micropatterns, porous membrane and trenches. Precisely controlled physical dimensions, layouts, and topography as well as different surface chemical treatments were applied to study their influences on nasopharyngeal carcinoma cell (10-15 μm in diameter) migration in mimicked platforms over 15-hour of time-lapse imaging. By placing the pores at different distance from the edges of the trenches, pores with different trench sidewall exposures and effective sizes were generated. Pores right next to the trench sidewalls showed the highest cell traversing probability, most likely related to the larger surface contact area with cells along the sidewalls. Straight grating oriented perpendicular to trenches below the top layer increased cell traversing probability. Pore shape as well as pore size influenced the cell traversing probability and cells could not traverse through pores that were 6 μm or less in diameter, which is much smaller than the cell size. Trench depth of 15 μm could induce more cells to traverse through the porous membrane, while shallower trenches impeded cell traversing and longer time was needed for cells to traverse because 3 and 6 μm deep trenches were much smaller than cell size which required large cell deformation. Hydrophobic surface coating on the top layer and fibronectin in pores and trenches increased the cell traversing probability and reduced the pore size that cells could traverse from 8 to 6 μm, which indicated that cells could have larger deformation with certain surface coatings.

Controlled Scaffold Platform Designs on Nasopharyngeal Carcinoma Cell Separation

“…The depth of the bottom layer was maintained at 15 μm, while the top layer thickness was changed from 5, 10, 15, and 30 μm. The trench depth of the top layer is correlated with the space available for cells to migrate in, which could influence the traversing behaviors of cells [55]. The highest traversing probability was achieved when the top layer was 15 μm deep, with 66.3% for NPC43 cells and 5.5% for NP460 cells, as shown in Fig.…”

Enhancing Nasopharyngeal Carcinoma Cell Separation with Selective Fibronectin Coating and Topographical Modification on Polydimethylsiloxane Scaffold Platforms

“…The narrower 5 µm wide trenches would limit most of the NP460 cells to migrate into the trenches while still allowing many NPC43 cells to squeeze through, especially when the sidewalls of top layer trenches and bottom layers were coated with 50 µg/mL FN. Typical NP460 and NPC43 cell sizes are 15-20 µm, but NPC43 cells are more flexible and deformable, which allows them to squeeze into the narrower trenches [14,25,28]. The second approach was to decrease the concentration of the FN coating on the sidewalls of the top layer trenches and the bottom layer from 50 µg/mL to 10µg/mL to lower the attraction force for NP460 cells to move into the 5 µm wide trenches.…”

“…The prepared platforms were mounted on Si wafers and exposed to the plasma. A gentle approach using a barrel plasma system (GIGAbatch 310M, PVA TePla, Wettenberg, Germany) was employed to generate low-energy reactive species, a common technique to make the PDMS surface hydrophilic for cell studies [5,[25][26][27][28]. In addition, O 2 and Ar plasma treatments were carried out using a different plasma system (LPX ICP-SR, SPTS, Newport, UK) and two separate RF power supplies.…”

“…The ECM functions as a complex scaffold for cells in the tissue, encompassing varied physical dimensions and surface properties that influence NPC cell migration and traversing behaviors. Previous studies have demonstrated the influential role of topographical features in the ECM in guiding cell migration, with a focus on controlling the dimensions and layouts of 3D PDMS scaffold platforms to realize the NPC cell separation [25][26][27][28][29]. The concept of utilizing these topographical features to direct cell adhesion, seeding, viability, and migration on two-dimensional surfaces has been well established [9,18,20,22,[30][31][32].…”

Advances in Regulating Cellular Behavior Using Micropatterns

“…In terms of cell migration on 3D patterns, Liu et al [81] designed a 3D PDMS platform to mimic ECM containing blood vessels for studying tumor metastasis. The platform is composed of three layers: the top layer features 2 μm grooves with 2 μm ridges, the middle layer comprises 14 μm deep pores, and the bottom layer consists of 30 μm wide and 15 μm deep grooves.…”