FIGURE 4.

ATO plays a dramatic function in inhibiting the tumorigenesis of P cells. (A) Nude mice‐bearing P cells and D cells xenograft tumours for 12 days, and ATO was administered by i.p. injection once at 10 mg/kg every two days, six times in total. Then, the mice were sacrificed and tumours were removed, photographed and measured. (B) After implantation, tumour volumes were measured with a slide calliper every two days. (C) Tumours as shown in (A) were used to do the Ki67 immunostaining, and the intensity of Ki67 was measured and shown in (D), scale bar, 100 µm. *p < 0.05 and **p < 0.01, compared between the P cells and D cells