PROBLEM TO BE SOLVED: To provide placental stem cells exhibiting increased survival, compositions containing such placental stem cells, and methods of using such placental stem cells and compositions. An isolated placental stem cell that exhibits increased survival when cultured under one or more conditions that cause cell death, such as regulatory RNA. An isolated placental stem cell, wherein the molecule is contacted with at least one survival-related gene and is expressed at a reduced level as compared to expression of the same survival-related gene in a corresponding unmodified placental stem cell. [Selection diagram] Figure 1【課題】生存の増加を示す胎盤幹細胞、そのような胎盤幹細胞を含む組成物、並びにそのような胎盤幹細胞及び組成物を使用する方法の提供。【解決手段】細胞死を引き起こす1以上の条件下で培養されたとき、対応する未修飾の胎盤幹細胞と比べて生存の増加を示す、単離された胎盤幹細胞であって、例えば、調節性ＲＮＡ分子を少なくとも1つの生存関連遺伝子と接触させ、対応する未修飾の胎盤幹細胞における同じ生存関連遺伝子の発現と比較して減少したレベルで発現する、単離された胎盤幹細胞。【選択図】図１
