It is an object of the present invention to specify miRNA associated with the treatment and/or prevention of various cancer species, from among various miRNAs associated with cancer, and to provide a novel pharmaceutical composition for treating and/or preventing cancer which targets the specified miRNA. According to the present invention, provided are a pharmaceutical composition for treating and/or preventing cancer comprising, as an active ingredient, an antisense polynucleotide shown as hsa-miR4454, a combination drug comprising the aforementioned pharmaceutical composition and another antitumor agent, and a method for treating and/or preventing cancer, using the above-described pharmaceutical composition or combination drug.