Fig 2: Function of CKS1 in HCT116 and SW620 cells. pCDNA3.1-CKS1-RFP plasmids were transfected to HCT116 and SW620 cells to study the function of CKS1 in colon cancer cells, pCDNA3.1-RFP plasmids transfected cells were used as controls; a CCK-8 assay was used to measure the proliferation ratio of HCT116 cells post plasmid was transfected for 12 h, 24 h and 48 h, respectively; b CCK-8 assay was used to measure the proliferation ratio of SW620 cells post plasmid was transfected for 12 h, 24 h and 48 h, respectively; c the colony formation ability of HCT116 cells was measured and statistically analyzed using a colony formation assay following 10 days of culture; d the colony formation ability of SW620 cells was measured and statistically analyzed using a colony formation assay following 14 days of culture. *Indicates p < 0.05 for three independent experiments analyzed by Student’s t test

Fig 3: SAHH, BLM, CKS1B, and PKMYT1 are important for survival of MYCN-amplified neuroblastoma cell lines. A, apoptosis assay was carried out as indicated in Fig. 6A. The error bars indicate standard deviations, and statistical significance was assessed using Student's t test. B, Q-PCR was used to assess gene expression in naturally MYCN-amplified neuroblastoma cell lines 1 week after infection with shRNA lentiviral vectors targeting no gene (shSCR) or AHCY, AURKA, CKS1B, BLM, or PKMYT1 (shGENE). Gene expression levels in cells infected with the control virus were set to 1. Q-PCRs were performed in triplicate. Error bars indicate standard deviation.

Fig 4: Function of PADI3 on CKS1 overexpression induced cell colony formation and proliferation in HCT116 cells. a GFP stable expressing HCT116 cells as the negative control, CKS1stable expressing HCT116 cells as the positive control, PADI3 overexpression plasmid was transfected into the CKS1 stable expressing HCT116 cells to study the function of PADI3 on CKS1 induced cell colony formation activity, 5 µM 17-AAG was used to treat CKS1stable expressing HCT116 cells to study the function of 17-AAG on CKS1 induced cell colony formation activity; b statistic analysis of colony formation results in a; c CCK8 was used to study the function of PADI3 and 17-AAG on CKS1 induced cell proliferation at 0 h, 12 h, 24 h and 48 h. *Indicates p < 0.05 for three independent experiments analyzed by Student’s t test

Fig 5: Function study of CKS1 in vivo. CKS1-expressing HCT116 cells were injected into the BALB/c nude mice to study the function of CKS1 in tumorigenesis, GFP-expressing HCT116 cells were injected into the BALB/c nude mice as the control group; a western blot analysis was used to confirm CKS1 expression level both in CKS1-expressing HCT116 cells and in GFP-expressing HCT116 cells; b tumors were dissected 42 days after cell injection, the upper group of tumors was developed from CKS1-expressing HCT116 cells, and the lower group of tumors was developed from GFP-expressing HCT116 cells; c tumors weight were measured and statistically analyzed; d qRT-PCR was used to measure the expression level of CKS1 in the tumor tissues dissected after 42 days injection. *Indicates p < 0.05 for three independent experiments analyzed by Student’s t test