CCNE1 and prostate cancer: We previously reported that PGC‐1α was downstream of Cyclin E1 and PGC‐1α was reported to regulate polyamine synthesis in prostate cancer.14, 15 We therefore queried the expressions of PPARGC1 against polyamine genes and found that the expressions of SMS, SRM, and ODC1 were positively correlated with that of CCNE1, respectively (Figure 1C).