Malignant melanoma is the most aggressive and lethal form of skin cancer with an increasing incidence worldwide. In the past 5 years, the Food and Drug Administration has approved six targeted therapies or immunotherapies for the treatment of metastatic melanoma (Chapman et al., 2011; Falchook et al., 2012; Hauschild et al., 2012; Hodi et al., 2010; Ribas et al., 2015; Topalian et al., 2014). For the first time, interventions improve survival of this deadly disease. However, rapid resistance to BRAF/MEK inhibitors and lower rates of objective response or immune-related side effects for anti-CTLA-4 or anti-PD-1 monoclonal antibodies limited their widespread clinical applications.