Mmu-miR-505-5p was downregulated in Sca-1+CD31− compared to Sca-1+CD31+ cells, with targets Cyp1b1, Dcbld2, Igf1, and Ppp1r14b,Txndc5 increased in expression; Igf1 was involved in mTOR and PI3K-Akt signaling and Cyp1b1by with microRNAs in cancer. This evidence concerns the gene CYP1B1 and cancer.