Fig 2: Regulation of STC2 on sunitinib efficacy in Caki-1 cells under hypoxia condition. Determination of cell viability of Caki-1 cells treated with or without 5 μM Sun, 5 μM sunitinib + 0.2 μg/ml STC2-neutralizing antibodies siRNA-STC2 knockdown + 5 μM Sun or 5 μM Sun + 500 ng/ml hSTC2 by MTT (A). The cell proliferation of Caki-1 cells was determined by immunofluorescence staining of proliferation maker Ki-67 and quantified by the software Image J 1.54c (B, C). The cells were incubated with 5 μM Sun + 0.2 μg/ml STC2-neutralizing antibodies, or 5 μM Sun + 500 ng/ml hSTC2 for 24 h, the accumulation of s Sun in Caki-1 cells were observed by phase contrast microscopy (D). * P<0.05, ** P<0.01, indicate significant difference. Sun, sunitinib.

Fig 3: Effects of STC2-neutralizing antibodies on EMT, migration and invasion of Caki-1 cells treated with sunitinib under hypoxia condition. After treated with or without 5 μM Sun, 5 μM Sun + 0.2 μg/ml STC2-neutralizing antibodies for 24 h, the protein levels of EMT biomarkers in Caki-1 cells were evaluated by Western blotting (A), and quantified by Image J (B). The cell migration and invasion of Caki-1 cells were evaluated by wound healing assay and transwell (C-F). *, P<0.05; **, P<0.01 indicate significant difference. Sun, sunitinib.