(A-C) RKO or SW48 cells were transfected with pCDNA4 (vector; V), full-length pCDNA4-PHB1 (FL), or pCDNA4-PHB1ΔNES (ΔNES) for 72 hr. (A) Immunofluorescent staining of RKO cells. Scale bars: 20 μm; boxed pullouts: 20 μm. (B) Mean ± SEM of relative AXIN1 mRNA expression. (C) Cell viability as measured by LDH release. (D-G) RKO or SW48 cells were transfected with 2 unique siRNAs against PHB1 or siNegative Control (siNC) for 48 hr. (D) Mean ± SEM of relative AXIN1 mRNA expression. (E) Representative western blot of β-catenin, AXIN1, or PHB1 (to demonstrate efficiency of siRNA knockdown). (F) Mean ± SEM of densitometric units by western blotting. (G) Relative luciferase expression of transcriptional activation by β-Catenin after 10 μM XAV939 or vehicle treatment for 16 hr. Negative control (NC) cells were transfected with a non-inducible firefly reporter construct. n = 3 (A, D-G) or n = 6 (B, C) biological replicates per group. *P < 0.05, **P < 0.01 vs V by unpaired, two-tailed Student’s t test (B, C); *P < 0.05 vs siNC vehicle, #P < 0.05, ##P < 0.01 vs siPhb1 vehicle by one-way ANOVA (D, F) or two-way ANOVA followed by Bonferroni’s test (G).