The characteristics of Ishikawa endometrial cancer cells are modified by substrate topography with cell-like features and the polymer surface

Abstract

Conventional in vitro culture studies on flat surfaces do not reproduce tissue environments, which have inherent topographical mechanical signals. To understand the impact of these mechanical signals better, we use a cell imprinting technique to replicate cell features onto hard polymer culture surfaces as an alternative platform for investigating biomechanical effects on cells; the high-resolution replication of cells offers the micro- and nanotopography experienced in typical cell–cell interactions. We call this platform a Bioimprint. Cells of an endometrial adenocarcinoma cell line, Ishikawa, were cultured on a bioimprinted substrate, in which Ishikawa cells were replicated on polymethacrylate (pMA) and polystyrene (pST), and compared to cells cultured on flat surfaces. Characteristics of cells, incorporating morphology and cell responses, including expression of adhesion-associated molecules and cell proliferation, were studied. In this project, we fabricated two different topographies for the cells to grow on: a negative imprint that creates cell-shaped hollows and a positive imprint that recreates the raised surface topography of a cell layer. We used two different substrate materials, pMA and pST. We observed that cells on imprinted substrates of both polymers, compared to cells on flat surfaces, exhibited higher expression of β1-integrin, focal adhesion kinase, and cytokeratin-18. Compared to cells on flat surfaces, cells were larger on imprinted pMA and more in number, whereas on pST-imprinted surfaces, cells were smaller and fewer than those on a flat pST surface. This method, which provided substrates in vitro with cell-like features, enabled the study of effects of topographies that are similar to those experienced by cells in vivo. The observations establish that such a physical environment has an effect on cancer cell behavior independent of the characteristics of the substrate. The results support the concept that the physical topography of a cell’s environment may modulate crucial oncological signaling pathways; this suggests the possibility of cancer therapies that target pathways associated with the response to mechanical stimuli.

Tumour Initiation: a Discussion on Evidence for a “Load-Trigger” Mechanism

“…A small set of our results is presented in Fig. 1c [46]. Here we illustrate that cancer cells of the Ishikawa cell line, when cultured on a substrate imprinted with cell-like features, exhibited different properties to cells cultured on a flat surface.…”

“…Bottom: a cartoon of cells attached at focal adhesion points (yellow dot) to substrate. c The effect of topography (flat, yellow; negative, blue; positive, burgundy) on Ishikawa cancer cells is illustrated for cytokeratin-18 expression (left), β1-integrin expression (centre) and cell number (right) following 60 h culture [46] (with permission of Dove Medical Press)…”

“…These three studies [38, 42, 46] and others, e.g. [47–49] using different models, observed that the physical characteristics of the substrate regulated central factors of cell functioning and of the cancerous phenotype, independent of gene modification.…”

Precision Medicine Gains Momentum: Novel 3D Models and Stem Cell-Based Approaches in Head and Neck Cancer

“…These bioimprints provide in vitro substrates with cell-like features and enables to investigate effects of physical topographies that are similar to those experienced by cells in vivo ( Tan et al, 2015 ). Materials used for bioimprints are for example polydimethylsiloxane (PDMS), polystyrene (pST), polymethacrylate (pMA), and some others ( Murray et al, 2014 ; Mutreja et al, 2015 ; Tan et al, 2015 ). How such bioimprints are created is well described in the studies of Murray et al (2014) , Tan et al (2015) .…”

“…Materials used for bioimprints are for example polydimethylsiloxane (PDMS), polystyrene (pST), polymethacrylate (pMA), and some others ( Murray et al, 2014 ; Mutreja et al, 2015 ; Tan et al, 2015 ). How such bioimprints are created is well described in the studies of Murray et al (2014) , Tan et al (2015) .…”