PAR1-stimulated breast carcinoma invasion is suppressed by ARRDC3 and JNK inhibition.
A, MDA-MB-231 HA-ARRDC3 pSLIK cells treated with or without 1 μg/ml DOX for 48 h were serum-starved cells, seeded onto transwells coated with Matrigel, and incubated with or without 1 pm α-thrombin (α-Th) for 5 h at 37 °C. Cells were fixed, stained, and imaged. Images shown are representative of three independent experiments. The data (mean ± S.D. (error bars), n = 3) were quantified from nine different fields of view at ×10 magnification for each condition and are represented as the -fold change over untreated control cells. Statistical significance was determined by unpaired t test (***, p < 0.001; n = 3). B, MDA-MB-231 HA-ARRDC3 pSLIK cells were preincubated with DMSO or 20 μm SP600125 JNK inhibitor for 2 h at 37 °C, seeded onto transwells coated with Matrigel, and then treated with 1 pm α-Th. Cells were processed, and statistical significance was determined by unpaired t test (****, p < 0.0001; n = 3). The inset shows effects of DMSO and SP600125 on α-Th–stimulated phosphorylation of JNK and p38; cell lysates were immunoblotted for total JNK and p38 as a control (Ctrl).