Figure 6.

CDK7 inhibition reduced osteosarcoma cell clonogenicity in vitro and decreased the spheroid diameter of osteosarcoma cell lines in a three-dimensional (3D) cell culture. (a) Representative results of colony formation in KHOS and U2OS. The numbers of colonies and their sizes were markedly decreased in cells treated with BS-181. (b, c) Representative images of KHOS and U2OS were measured after 10 µM of BS-181 treatment in a 3D cell culture. Spheroid formation of (b) KHOS and (c) U2OS were significantly smaller than untreated cells at all observation points. Cell fluorescence images of spheroid formation were taken after 12 days of cultivation (scale bar, 100 µm). (d, e) The average relative spheroid diameter of (b) KHOS and (c) U2OS treated with CDK7 inhibitor compared with untreated cells at an observation point of 12 days. The data are mean ± SE of the two experiments carried out in triplicate (** indicates p < 0.001).

CKD7, cyclin-dependent kinase 7.