CCDC26-KD clones in culture medium containing high or low serum. Growth of CCDC26-KD clones in culture medium containing 15% (A) or 0.1% FBS (B). The results show the mean of three or four independent experiments. P values for difference between non-KD (K562 and Vec, GER vector transformed) and KD (22B11, 32H8, 3–4 and 3D1) groups are shown. C: Number of dead cells after serum depletion measured by PI staining and flow cytometry. The results indicated the average of two independent experiments. P values for differences between non-KD and KD groups are shown. D: An example of flow cytometry analysis of cells 72 hours after serum depletion.