Supplementary Figure S4. Activation of Stat3/Myc signaling is specific to Ptenpc-/-; Trp53pc-/-prostate and leads to stromal expansion. from MYC Drives Pten/Trp53-Deficient Proliferation and Metastasis due to IL6 Secretion and AKT Suppression via PHLPP2

Supplementary Figure S4. Activation of Stat3/Myc signaling is specific to Ptenpc-/-; Trp53pc-/-prostate and leads to stromal expansion. (A) H&E analysis of prostates from all studied genotypes reveals massive stromal expansion after co-deletion of Pten and Trp53. IHC analysis confirms stromal pStat3/ Myc activation specifically in Ptenpc-/-; Trp53pc-/- prostate. Note that pAkt activation is restricted to gland, consistent with triggering paracrine Il6/Stat3/Myc activation. Scale Bars, 100 μm. (B) Pten is present in the stroma of Ptenpc-/-; Trp53pc-/- prostates confirming that the expansion of stroma is not driven by spurious Pten/Trp53 recombination. (C) Proliferation in the Ptenpc-/- glands correlates with Akt activation, in contrast to Ptenpc-/-; Trp53pc-/- glands, where it correlates with Stat3/ Myc staining.