Figure.4.

Tumor-on-a-chip models to generate mechanical factors. A. A PDMS cylindrical channel coated with collagen to grow a monolayer of cancer cells. Media flow generated wall shear stress and induced cell filopodia extension. (reproduced with permission from ref. 87) B. Microfluidic design for multiple constriction-relaxation regions along the channels with comparable size to cells for cell deformation testing. (reproduced with permission from ref. 94) C. Channels with micropillars in the center blocked cell motion with flow. (reproduced with permission from ref. 96) D. Micropost array for CTC separation from a blood sample. (reproduced with permission from ref. 99) E. 2D chemical-ECM stiffness gradient setup. A chemical gradient was generated through double laminar flows in a Y-shape channel with different chemical concentrations. ECM stiffness gradients were created by photo-polymerization of ECM with a moving opaque mask. (reproduced with permission from ref. 114)