Fig. 5.

Cancer cells seeded onto gels that mimic tumor ECM stiffness recapitulate in situ gene expression. (a-e) Z-normalized expression levels of selected mouse genes whose human orthologs are involved in (a) apoptosis, (b) cell signaling, (c) cell cycle and growth, (d) response to drug and (e) small molecule metabolism and transport pathways. Gene expression of primary mammary tumor cells is shown for the in situ cells (isolate) immediately after removal, or following their culture for 5 days on soft gels (5 kPa), intermediate stiffness gels (30 kPa) or the highly rigid glass control surface. (f) Folds change (units of log₂; p<1×10⁻⁶) in the expression of genes associated with resistance (orange) or sensitivity (purple) of cells towards PTX and DOX between cells seeded onto soft (5 kPa) gels versus glass. Data is averaged from n ≥ 3 biologic replicates.