Consistent with the results obtained from the two-dimensional colony formation assay, the average diameter of cancer spheroids formed from U2OS-EZH2-siRNA and SAOS-EZH2-siRNA cells was significantly lower than the diameter formed from U2OS-NS and SAOS-NS in the three-dimensional cell culture environment (Figure 3J, 3K). The gene discussed is EZH2; the disease is cancer.