Fig. 4
Upregulated expression of DAB2IP enhances the killing-effect of IR on ESCC cell xenografts. A Kyse150-DAB2IP or control Kyse150-vectorcells (106) were injected subcutaneously into right flank of athymic nude mice, respectively. When the volume of a transplanted tumor grew to 180 mm3, the tumors were received 6 Gy dose of IR. The tumor volume of xenografts was measured with calipers every 3 days for a total of 33 days. Overexpressed DAB2IP alone did not affect the growth of the tumors; the mean tumor volume in the Kyse150-vector and Kyse150-DAB2IP groups was 936 ± 68 mm3 and 989 ± 76 mm3, respectively (n = 7, p = 0.1943, Student’s t test). However, when treated transplanted tumor with 6 Gy dose of IR, the mean tumor volume of the Kyse150-vectorgroup was significantly larger than that of the Kyse150-DAB2IP group (423 ± 43 mm3 vs. 287 ± 38 mm3, p ≤ 0.05). The values represent mean tumor volume ± SD. B Representative images of DAB2IP IHC staining in Kyse150-vector and Kyse150-DAB2IP transplanted tumor tissues. C Nude mice xenograft from Kyse150-vector and Kyse150-DAB2IP cells were treated with 6 Gy dose of IR, and 0 or 24 h later, immunofluorescence with antibodies with γH2AX (green) and 53BP1 (red) was performed. Merged spots (yellow) show colocalization of 53BP1 and γH2AX foci at DSBs. Experiments were performed three times and a representative result is shown