HDAC9 and cancer: For instance, co-administration of the HDAC inhibitor SAHA with vismodegib has been shown to suppress tumor growth in multiple aerodigestive cancer cell lines (Chun et al., 2015), and the dual HDAC/HH pathway inhibitor NL-103 effectively overcomes vismodegib resistance conferred by SMO-M2 and SMO-D473H mutants by downregulating the expression of GLI2 (Zhao et al., 2014).