Differential gene expression in human keratinocytes cultured on different substrate topographies (S1 and S2) for 1h, 4h and 12h.

Substrate topography has emerged as a novel regulator of cell fate behaviour in keratinocytes (Zijl, Acta Biomater, 2019). Specifically, small circular micropillars (S1) can induce the differentiation of spread cells, and larger triangular substrates (S2) can inhibit differentiation in kerinocytes. Here we investigated the potential molecular mechanisms behind these processes. We chose timepoints previously shown to be associated with differentiation in suspension cultures (Mishra, eLife, 2017), in order to find early regulators of the differentiation process. Our results show a delay in differentiation on S2 substrates and an upregulation of differentiation pathways on S1. Beyond this, no clear mechanistic regulators of the differentiation program were found.