PER1 and cancer: In TCGA and GEO cohorts, the advanced FIGO stages implied high risk score (Figure S9) and FIGO stages were classified according to metastasis.  PGCCs, a type of cancer stem cells with more invasion and metastasis ability, obtained higher risk scores than the control group (Fig. 7K), albeit the varied expression of PER1, AKAP12 and MMP17 in HEY and SKOv3 cell lines (Fig. 7I, J).