Fig. 1: PSPC1 interacts with nuclear tumor suppressive PTK6 to inhibit tumor progression.

a The PSPC1 immunoprecipitated (IP) complex of Huh-7 cells lysates with anti-PSPC1 antibody analyzed by Western blotting (IB) with the indicated antibodies (IP/Western). b Endogenous PSPC1 and PTK6 interaction analyzed by IP/Western blotting analysis in Huh-7 cells. Preimmune IgG is the control, and the arrowhead is the IgG heavy chain. c Interaction of PSPC1 with PTK6 by ectopic expression of HA-tagged PSPC1 and/or Flag-tagged PTK6 protein in SK-hep1 cells by IP/Western analysis. d Subcellular distribution of wild-type (WT) and kinase-dead (KM) mutant of flag-tagged PTK6 in SK-hep1 cells expressing HA-tagged PSPC1 determined by Western blotting analysis. Sp1 and α-tubulin were used as internal controls for nuclear and cytoplasmic fractions, respectively. e–g PTK6 suppresses PSPC1-enhanced cell motility in a phosphorylation-dependent manner. The expression levels of HA-tagged PSPC1, His-tagged PTK6 wild-type (WT) or kinase dead (KM) mutant in SK-hep1 cells analyzed by Western blotting analysis (e). Expression of PTK6, but not KM mutant of PTK6, suppressed PSPC1-mediated cell migration (f) and invasion (g) in SK-hep1. Data are represented as mean ± SEM (n = 4). h–j PTK6 suppresses PSPC1-enhanced cell motility reversed by PTK6 knockdown. PTK6 knockdown efficiency of shRNAs (shRNA#52 and shRNA#53) and Western blotting analysis in SNU-387 cells expressing HA-tagged PSPC1 (h). PTK6 knockdown increased cell migration (i) and invasion (j) in SNU-387 cells. shLuc is a control shRNA targeting luciferase. Data are represented as mean ± SEM (n = 4). All data statistics based on: *p < 0.05, **p < 0.01, ***p < 0.001 by one-way ANOVA with Brown–Forsythe test. Source data are provided as a Source Data file.