AIG1 and granular cell tumor: In order to examine whether AR signaling was compromised in GCT of p130CasΔepi– mouse, we assessed the mRNA levels of several downstream targets of the AR pathway which specifically expressed in GCT cells, such as EGF, NGF, KLK 124, cysteine-rich secretory protein 3 (Crisp 3)22,25, prostate transmembrane protein, and androgen-induced 1 (Pmepa 1)26, cystic fibrosis transmembrane regulator (Cftr)27–29, and Runt-related transcription factor 1(Runx 1)22,30.