Fig. 2: Comparison of mechanical properties between normal tissue/cells and tumor tissue/cells or between tumors with different levels of malignancy.

A Magnetic resonance elastography (MRE) imaging and measurement of tumorous and normal liver tissues. Malignant tumor tissue is mechanically stiffer than normal tissue [435]. B Second harmonic generation (SHG) imaging shows crosslinking ECM in tumor tissues and loose ECM in normal tissues [53]. C Tumor cells show lower mechanical stiffness than normal cells [109]. D Higher and more polarized contractility (demonstrated by magnitude and local concentration of traction forces) in invasive breast cancer cells MDA-MB-231 and lower and nonpolarized traction force in noninvasive MCF-7 breast cancer cells [176]. E Cell-cell adhesion (indicated by expression amount and distribution of cell adhesion molecule E-cadherin) is lower in disassociated colon cancer HCT-8 cells than in nondissociated HCT-8 cell island [436]. F Invasive MDA-MB-231 breast cancer cells show lower cell-ECM adhesion than noninvasive MCF-7 breast cancer cells [165]. G Ovarian epithelial cells’ actin cytoskeleton contains linearized F-actin, while ovarian cancer cells’ cytoskeleton shows crosslinking F-actin [112]. H Normal bronchial cells show round nucleus (purple) with finely granular heterochromatin (dark-violet) while small-cell lung carcinoma cells show elongated or random shaped nucleus (purple) with clumping chromatin (dark-violet) [188]. I Highly metastatic BW-19 lymphoma cells (A) have higher cell membrane stiffness than low metastatic BW-19cl1 cells (B) [205].