Fig. 5

ATO and ATRA cooperatively ablate Pin1 and inhibit multiple Pin1-regulated oncogenic pathways and tumor growth in TNBC in vitro and in vivo including PDOXs. a ATO and ATRA cooperatively turn off many oncoproteins and on many tumor suppressors, like Pin1 KO. The 231 and 159 cells were treated with different concentrations of ATO and/or ATRA for 72 h, followed by IB, with Pin1 KO cells as controls. b–d ATO and ATRA cooperatively induced global protein expression like Pin1 KO. The 231 cells were treated with ATO and/or ATRA or DMSO for 72 h, followed by quantitative mass spectrometry analyses, with Pin1 KO 231 cells as a control. Three thousand seven hundred and fifty-eight proteins passed the abundance filter (b), and 209 proteins were altered by >1.5-fold (c). The log 2 transformed ratio of treated versus control was used to generate the heatmap in GENE-E. The Spearman's correlation matrix for the 209 altered proteins are shown and their P values are all below 2.2e−16, except P value for ATO and Pin1 KO being 3.5e−12 (d). e ATO and ATRA globally upregulates microRNA expression like Pin1 KO. MicroRNAs of ATO-treated and/or ATRA-treated 231 cells and Pin1 KO 231 cells were profiled by NanoString. Data are presented as relative to microRNA expression of DMSO-treated (Ctrl) 231 cells or vector CRISPR 231 cells through the dot density plot. The P values were determined by Student’s t test. f–h ATO and ATRA cooperatively inhibit tumor growth in TNBC 231 orthotopic xenografts. The 231 cells were transplanted into mammary fat pads, and 1 week later, treated with ATO and/or ATRA. Tumor sizes were measured (f) and mice were sacrificed after 6 weeks to collect tumor tissues (g) and measure their weights (h). i–n ATO and ATRA cooperatively inhibit tumor growth in TNBC PDOXs. TNBC patient-derived tumors were transplanted, followed by treating mice with ATO and/or ATRA 2–3 weeks after xenograft when tumors were notable (i–k) or reached about 360 mm³ (l–n). o ATRA induces AQP9 to cooperate with ATO to downregulate Pin1 and Pin1 oncogenic substrates and upregulate Pin1 tumor-suppressive substrates in human cells and PDOXs, assayed by immunoblot. The results are expressed as mean ± SD and the P values were determined by ANOVA or Student’s t test. n = 4–5 mice