RRM2 and cancer: Furthermore, marker gene expression analysis indicated that LCAs and their original tumors showed similar expression profiles of cancer stem cell-related genes (e.g., SOX2, SIX2, EPHB2), CAF-related genes (FAP), ECM-related genes (e.g., COL3A1, COL5A2, COL10A, VCAN), immune cell-related genes (e.g., CXCL8, CXCL6, TNFSF11, IL4I1) and cancer cell-related genes (e.g., TOP2A, ASPM, S100P, RRM2) (Fig. 4d), indicating that LCAs largely maintained the cellular heterogeneity of parental tumors.