Platinum-based drugs are among the most active anticancer agents available and are used widely for the treatment of a variety of human solid tumors. Although patients show high response rates to platinum drugs, most patients develop resistance to these drugs during treatment. Because the acquisition of resistance is a major obstacle to the clinical use of platinum drugs, the processes by which cells develop such resistance are of great interest and efforts have been made to overcome this problem. Both mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K) cascades are involved in resistance to these drugs, and clinical trials of some small-molecule inhibitors of the MAPK and PI3K-Akt cascades to overcome resistance to platinum drugs are ongoing.