A synthetic peptide that targets cancer stem cells is provided. The peptide consists of the amino acid sequence of anyone of SEQ ID NO: 1 to SEQ ID NO: 15. Also provided is a composition comprising said synthetic peptide with a therapeutic agent fused thereto, and a pharmaceutically acceptable carrier or diluent. Further provided is a method of screening a peptide specifically targeting to a cancer stem cell. The method comprises the steps of establishing an oligopeptide library by using a phage expression system, contacting the library with a culture of bulk tumor cells of a cancer cell line, contacting the phages which do not bind to the bulk tumor cells with a culture of cancer stem cells of said cancer cell line, and screening a peptide specifically targeting to a cancer stem cell from the phages which bind to the cancer stem cells.本發明係提供一種靶向癌幹細胞的合成胜肽。該胜肽係由SEQ ID NO: 1至SEQ ID NO: 15中任一者之胺基酸序列組成。本發明亦提供一種組合物,包含所述合成胜肽,其具有接合至其上之治療劑,以及一醫藥上可接受之載體或稀釋劑。本發明更提供一種篩選特異性靶向癌幹細胞之胜肽的方法。該方法之步驟包含利用噬菌體表現系統建立寡胜肽庫、以癌細胞株之腫瘤實質細胞培養物接觸該庫、以該癌細胞株之癌幹細胞培養物接觸未結合至該腫瘤實質細胞之噬菌體、及由結合至癌幹細胞之噬菌體篩選特異性靶向癌幹細胞之胜肽。
