HDAC9 and non-small cell lung carcinoma: Studies on the antitumor effects of EGFR-TKIs or EGFR-TKIs combined with HDAC inhibitors on NSCLC have also demonstrated that HDAC inhibitors decrease the survival rates of A549, hcc827, and hcc827ir cells, and enhance the sensitivity of EGFR-TKI-resistant cell lines to EGFR-TKIs through synergistic effects (91, 92).