Differential effects of modulation of SOCS3 expression and STAT3 inhibition on HNSCC migration.

<p>(A) Representative phase-contrast images of the in vitro wound area in the different cell cultures (100×magnification) for the gain of function experiments by transfection of a CMV-driven SOCS3 expression plasmid or the empty vector control. STAT3 biochemical inhibitor was used to assess possible effects of SOCS3 that are independent of modulation of STAT3 activity. The distance between the edges of the wound was measured on digital images captured adjacent to the reference notch made in the cell culture plastic (black area on the right of the images) Non-neoplastic HaCAT cells were transfected with the empty vector to control for non-specific effects of the transfection procedure on cell migration. Bars represent averages and vertical lines standard deviation of three independent wounding experiments, measured in triplicate (*p<0.05 indicates significant difference in comparison to the distance between edges of the wound at the same time period in empty-vector transfected cells). (B) Representative phase-contrast images of the in vitro wound area in the loss of function experiments by transfection of SOCS3 siRNA or non-targeting siRNA in OSCC3 cells. Quantitation of cell migration was performed as described in (A) and the graph represent average and standard deviations of three independent wounding experiments measured in triplicate.