Fig. 2

Intracellular S100A4 promotes proliferation of bone-metastatic prostate cancer cells. a, b Lentiviral transduction of S100A4 shRNA efficiently reduced S100A4 protein levels in mtPC3 cells (a) as well as S100A4 protein secretion in culture medium from mtPC3 cells (b). ***p < 0.001 by unpaired two-tailed Student’s t-test. c-e Proliferation of mtPC3 cells with control shRNA (mtPC3-C) vs. S100A4 shRNA (mtPC3-S) was analyzed with the CCK kit (c). Proliferation of mtPC3-C or mtPC3-S cells in the presence of BSA or recombinant human S100A4 (S100A4; 2 μg/ml) was analyzed with the CCK kit (d). Proliferation of mtPC3-C or mtPC3-S cells in the presence of control antibody or monoclonal anti-S100A4 antibody (4A; 30 μg/ml) was analyzed with the CCK kit (e). ***p < 0.001 by two-way ANOVA with post hoc Bonferroni’s test. N.S., not significant. Data are presented as the mean ± SD. The full-length gels are presented in Supplementary Fig. 3b