The study is a prospective, single-arm, one-site therapeutic trial of the combination of trametinib plus digoxin for advanced melanoma. endpoints are toxicities assessed by nCi CTCae v4.1 within the first 8 weeks, responses measured by ReCiST v1.1 criteria every 8 weeks with scans and exams, tumor sensitivity to the drug combination quantified by tumor regressions in nSG mice, and correlations of response with tumor sensitivity, BRaF status, MaPK inhibitor exposure history, and tumor sodium pump expression.