Certain embodiments of the invention provide a method for identifying a cancer cell that is sensitive to a biguanide compound or other CYP epoxygenase inhibitor, comprising detecting increased expression of at least one cytochrome P450 (CYP) and/or decreased expression of soluble epoxide hydrolase (EPHX2) in the cancer cell, wherein increased CYP expression and/or decreased expression of EPHX2 in the cancer cell correlates with increased sensitivity of the cancer cell to the biguanide compound or other CYP epoxygenase inhibitor.
