A novel use of 6-[3-(1-adamantyl)-4-methoxyphenyl]-2-naphthalenecarboxylic acid or a pharmaceutically acceptable salt or functional derivative thereof in treating a cancer, and in particular non-small cell lung cancer, is provided.本發明提供6-[3-(1-金剛烷基)-4-甲氧基苯基]-2-萘羧酸(或稱阿達帕林)或其醫藥可接受鹽或其功能性衍生物於治療癌症,特別是治療非小細胞肺癌的新穎用途。