DAPK1 is a critical downstream effector of HOXC9. (A) Genes involved in the regulation of autophagy were analyzed using qRT-PCR after knockdown of HOXC9 in the LN-229 cell line (error bars, SEM, n = 3). (B) DAPK1 protein expression levels were verified using Western blot analysis after knockdown of HOXC9. (C) DAPK1 and LC3B protein levels were detected by Western blot analysis after knockdown of DAPK1 by shRNA following HOXC9 downregulation. (D) Autophagy status was examined using immunofluorescence staining with LC3B antibodies after knockdown of DAPK1 (scale bars, 10 μm). (E) Beclin1 and LC3B protein levels were detected using Western blot analysis after knockdown of Beclin1 by shRNA following HOXC9 downregulation. For Western blot analyses, tubulin or GAPDH was used as the loading control. * P < .05, ** P < .01, *** P < .001.