PROBLEM TO BE SOLVED: To provide a biomarker for predicting an effect of an anti-c-Met antibody and/or selecting a subject for application of an anti-c-Met antibody, a reference marker for gene expression level comparison, and a method for predicting an effect of a c-Met antibody, the method comprising a step of measuring level of the biomarker in a biological sample.SOLUTION: Expression levels of genes in a group on which an anti-c-Met antibody has effects (efficacy group) and in a group on which an anti-c-Met antibody has no effect (non-efficacy group) are compared, and genes showing a great difference are selected. The selected genes or proteins encoded by the genes are suggested as biomarkers for predicting an effect of an anti-c-Met antibody. In addition, genes showing a small or no difference in expression level between different cells or individual cells of a same cell line are selected, and the selected genes or proteins encoded by the genes are suggested as reference biomarkers usable as control for comparison of expression level of a target gene and/or a target protein.【課題】抗ｃ－Ｍｅｔ抗体薬効予測及び／又は抗ｃ－Ｍｅｔ抗体適用対象の選別のためのバイオマーカー、遺伝子発現水準比較のための基準マーカー及び生物試料内の前記バイオマーカー水準を測定する段階を含むｃ－Ｍｅｔ抗体薬効予測方法の提供。【解決手段】抗ｃ－Ｍｅｔ抗体に対して効果を示す群（効能群）と効果を示さない群（非効能群）の遺伝子発現水準を比較して、差の大きい遺伝子を選別し、前記選別された遺伝子又はこれによってコードされるタンパク質を抗ｃ－Ｍｅｔ抗体の効能予測のためのバイオマーカー。また、細胞種類によって又は同一な種類の細胞でも個別細胞で発現水準の差が無いか少ない遺伝子を選別し、前記選別された遺伝子又はこれによってコードされるタンパク質を前記目的遺伝子及び／又は目的タンパク質の発現水準比較時のコントロールとして使用可能な基準とするバイオマーカー。【選択図】図３
