#$%^&*AU2014203224A120140710.pdf#####METHODS FOR DETERMINING CANCER RESISTANCE TO DEACETYLASE INHIBITORS ABSTRACT Described herein are methods and compositions for determining whether a particular cancer is 5 resistant to or susceptible to a histone deacetylase inhibitor or to histone deacetylase inhibitors. The methods include analysis of the expression levels of at least four biomarker genes associated with response to a histone deacetylase inhibitor. Also described herein are methods and compositions for increasing the likelihood of a therapeutically effective treatment in a patient, comprising an analysis of the expression levels of at least four biomarker genes associated with [0 response to a histone deacetylase inhibitor. Also described herein are isolated populations of nucleic acids derived from a cancer sensitive to or resistant to a histone deacetylase inhibitor. Further described are kits and indications that are used in conjunction with the aforementioned methods and compositions.