Figure 1.

Simulated microgravity exposure enhances cell migration and induces invasiveness in human keratinocytes. (a) HaCaT cells were grown until confluence and allowed to migrate for 24 hours (T₂₄) under simulated microgravity (μg) or normal gravity (1g) in a cell-free scratch area. The closure of the scratch area is higher in cells exposed to μg respect to cells kept at 1g. Cell migration was calculated as reported in methods (n = 3). (b) HaCaT cells were kept at 1g or exposed to μg for 24 hours. Cells were then seeded on uncoated (upper panels) or matrigel pre-coated (lower panels) transwell Boyden chambers and complete medium was added in the bottom chamber for chemotactic stimulation for 24 hours. Cell migration (upper panels) and invasion (lower panels) are significantly increased in μg cultures compared to control cells. Quantitative analysis was assessed as reported in methods and results expressed as mean ± standard deviation (SD) (n-4). Student’s t test was performed and significance level has been defined as follows: **p < 0.001 vs the control cells (1g).