Fig. 3.

DDB2 promotes IR-induced phosphorylation of ChK1 in lung cancer cells. a H1299 cells were transfected with DDB2-expressing vectors, treated with IR and further cultured for various time periods. Whole cell lysates were prepared and subjected to immunoblotting to detect various checkpoint proteins. b, c DDB2 was downregulated in A549 cells by transfecting with DDB2-specific siRNA (b) or in A549-pTRIPZ-shDDB2 cells by treating with Dox (c). Cells were treated with IR and further cultured for various time periods. Whole cell lysates were prepared and subjected to immunoblotting to detect phosphorylated Chk1. Lamin B was also detected as a loading control