HDAC9 and non-small cell lung carcinoma: We have previously described that increased expression of EZH2 in advanced NSCLC is a negative prognostic indicator and also a marker for chemotherapy resistance.5, 9 Given the interaction between EZH2 and HDAC, we evaluated the link between EZH2 expression and response to HDAC inhibition in NSCLC cell lines and explored the feasibility of using EZH2 expression as a biomarker of response to HDAC inhibitors in human tumors.