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The TopoChip library was prepared as reported previously [8] (link) and comprised 2175 different surface topographies and a flat control, printed on a polystyrene (PS) chip. Topographies were generated based on a random in silico combination of primitive shapes (circles, triangles, rectangles). Each individual TopoUnit (dimensions: 300 × 300 μm) contained a different kind of topography (composed of different primitive shapes). Different topographies not only varied in shape, but also, amongst other characteristics, in overall size, coverage and regularity. Each chip (dimensions: 2 × 2 cm², 66 × 66 TopoUnits) contained internal duplicates for every TopoUnit. The location of each TopoUnit was the same on every TopoChip. To rule out location bias, duplicate arrays were placed diagonally to each other. TopoChips were made from PS by hot embossing PS films (Goodfellow) [10] . Prior to cell culture, TopoChips were treated with oxygen plasma for 1 min or air plasma for 2 min (Zepto low cost plasma cleaner, Diener electronic) and sterilised for 5 min in 70% ethanol. When not directly used, TopoChips were stored dry and used within 6 months.

A detailed description of the surface fabrication procedures can be found elsewhere.^[28, ^41] Briefly, the TopoChip was comprised of 2176 unique surface topography combinations along with flat planar controls, printed on a polystyrene (PS) chip. Topographies were generated based on a random in silico combination of primitive shapes (circles, triangles, rectangles). Each individual TopoUnit (dimensions: 300 × 300 µm) contains a different kind of topography (composed of different primitive shapes) all at a height of 10 µm. Each chip (dimensions: 2 × 2 cm², 66 × 66 TopoUnits) contained internal duplicates for every TopoUnit. The location of each TopoUnit was the same on every TopoChip and to rule out location bias, duplicate arrays were placed diagonally to each other. TopoChips were made from polystyrene (PS) by hot embossing PS films (as described in Vermeulen et al.,).^[31] Prior to cell culture, TopoChips were treated with oxygen plasma for 30 s (Zepto low cost plasma cleaner, Diener electronic), placed in a 6‐well tissue culture‐treated polystyrene (TCP) plates (Corning Life Sciences), and incubated with complete media for 1 h at 37 °C.