Sex-biased Yap1 oncogene function

The incidence of many human cancers differs according to sex, but little is known about the interplay between oncogenic events and sex as a variable in tumorigenesis. Here we report that the oncogene Yap1 is sexually dimorphic in medulloblastoma progression and immune suppression. We show that Yap1 promotes stemness and blocks differentiation in sonic hedgehog (SHH)-subtype medulloblastoma by at least two distinct but complementary molecular mechanisms to regulate the RNA expression and protein functions of Sox2, Atoh1, NeuroD1, and Zic1/2. Yap1 also promotes an immune suppressive tumor microenvironment by directly regulating Csf1, Igf1, and Igfbp3 transcription and modulating IL6-JAK-STAT3, TNFR1, TGF-β, and CCL5 immune pathways. Notably, Yap1 function is more critical in males and this is evolutionarily conserved: genes downstream of YAP1 identified in mouse models stratify male but not female medulloblastoma patient survival. In summary, we demonstrate a sex-based function for an oncogene, underscoring the critical need to incorporate sex as a variable in cancer mechanism and clinical response studies, particularly those involving YAP1. ### Competing Interest Statement KY is a co-founder of EMPIRI, Inc. All other authors declare no competing interests.