The problem to be solved by the present invention is providing a targeting molecule and the like, which targets a target cell. The target cell is selected from a group consisting of a free stellate cell, a myoblast cell, a cancer-associated fibroblast cell, a tumor cell and a STRA6 (stimulated by retinoic acid gene) expression cell. In order to solve the aforementioned problem, the present invention provides a targeting molecule； a targeting agent, vector, complex and pharmaceutical composition containing the targeting molecule； a method for treating, checking, diagnosing or monitoring a disease associated with the aforementioned cell； and a method for marking, detecting or imaging the aforementioned cell. The targeting molecule is selected from a group consisting of (1) a peptide containing an amino acid sequence of a cell RBP (retinol conjugated protein) binding domain； (2) a peptide variation having a targeting capability equal to that of the peptide of (1)； and (3) a peptide analog having a targeting capability equal to that of the peptide of (1) or (2).本發明的問題是提供一種標靶化分子等，其將標靶細胞進行標靶化，該標靶細胞選擇自由星狀細胞、肌纖維母細胞、癌相關纖維母細胞、腫瘤細胞及視黃酸活化蛋白6(STRA6)表現細胞所組成之群組。為了解決上述問題，本發明提供一種標靶化分子；含有該標靶化分子之標靶化劑、載體、複合體及醫藥組成物；處置、檢查、診斷或監控與前述細胞相關的疾病的方法；及，將前述細胞進行標記、檢測或造影的方法。該標靶化分子，選擇自由(1)包含視黃醇結合蛋白(RBP)的細胞結合區域的胺基酸序列之胜肽、(2)具有與(1)的胜肽同等的標靶化能力之該胜肽的變異體胜肽、及(3)具有與(1)或(2)的胜肽同等的標靶化能力之胜肽模擬物所組成之群組。
