Fig. 7
Knockdown of scaRNA2 sensitized colorectal cancer to radiotherapy. Cell-derived xenografts (CDXs, A-G) and patient-derived xenografts (PDXs, H-M) were used to determine the influence of scaRNA2 knockdown on sensitivity to radiotherapy. A Schedule of the implantation of sg-ctrl and scaRNA2 knockdown HCT116 cells, local irradiation and measurement time points. B-C Tumour volumes in irradiated or unirradiated tumours were recorded every two days after local irradiation at a dose of 15 Gy. Tumour weight in the indicated four groups was measured on Day 30 after irradiation. ***P < 0.001 between the sg-ctrl + IR and sg-scaRNA2 + IR groups. D-G Immunohistochemical staining of p-ATR, p-Chk1, RAD51 and γH2AX in tumour tissues isolated from sg-ctrl and scaRNA2 knockdown tumours at 0, 8 and 24 h after irradiation. Quantification of the average density per field was performed for each group. ***P < 0.001 between the sg-ctrl + IR and sg-scaRNA2 + IR groups at each time point. H Schematic diagram depicting the establishment of the PDX model from rectal cancer patients. I Representative image of tumours in the sg-ctrl, sg-ctrl + IR, sg-scaRNA2 and sg-scaRNA2 + IR groups isolated on the 30th day after irradiation. J, K Tumour volumes in irradiated or unirradiated tumours were recorded every three days after local irradiation at a dose of 15 Gy. Tumour weight in the indicated four groups was measured on Day 30 after irradiation. ***P < 0.001 between the sg-ctrl + IR and sg-scaRNA2 + IR groups. L, M HE and immunohistochemical staining of TUNEL, Ki67 and γH2AX in tumour tissues isolated from negative control and scaRNA2 knockdown tumours after irradiation. Quantification of the average density per field was also performed in each group. ***P < 0.001 between the sg-ctrl + IR and sg-scaRNA2 + IR groups at each time point