Fig. 4

STAT3 and HP1α affect lung cancer cell growth in vitro. A549 cells stably expressing the indicated STAT3 or HP1α transgenes were subjected to clonogenic assay (a, b) and soft-agar assay (c, d). Represented images are shown. Colony numbers are presented as the mean value ± s.d. * indicates p < 0.05, ** P < 0.01, in Student’s t-test. (e) Box plots of tumor volumes 4 weeks after subcutaneous injection of A549 cells stably expressing the indicated constructs are shown. Each box shows the range of the second and third quartiles of tumor volumes. The “X” in the box indicates the median tumor volume. The bars (“whiskers”) represent the largest and smallest tumors. Six injections (n = 6) were done for each of the indicated transgene and cell line combination. n represents the number of injections for the indicated cell line. * and ** indicate p < 0.05 and p < 0.01 (Student’s t-test), respectively, when compared with the vector control or with control RNAi construct