Effect of cisplatin, topotecan, daunorubicin and hydroxyurea on human mesenchymal stem cells

Abstract

Mesenchymal stem cells (MSC) are important cellular component of the bone marrow microenvironment in supporting hemopoiesis. Li J et al reported previously that MSCs are resistant to chemotherapy commonly used in hematologic malignancies but are relatively sensitive to anti-microtubule agents. However, the response of MSCs to other chemotherapeutic agents commonly used in solid tumour settings remains unknown. This study was purposed to evaluate the acute direct effects of 4 individual chemotherapeutic agents on human MSCs (hMSC), including cisplatin, topotecan, daunorubicin and hydroxyurea. Using an in vitro culture system, the chemosensitivity of hMSC was determined by XTT assay and compared with NB-4 cells and normal peripheral blood mononuclear cells (PBMNC). The recovery of cell numbers following exposure to chemotherapeutic agents and apoptosis induced by chemotherapy in hMSC were evaluated. The results showed that although hMSCs were more resistant to the 4 agents above mentioned than NB-4 cells, they were sensitive to topotecan, cisplatin and daunorubicin than PBMNCs. The IC values of hMSCs for topotecan, cisplatin, hydroxyurea and daunorubicin were 636, 24.8, > 20 and 2.4 times of those of NB-4 cells respectively. The IC values of human PBMNCs for topotecan, cisplatin and daunorubicin were > 27, 1.9 and 1.4 times of those of hMSCs respectively. Reduction of cell number was observed in hMSCs treated with the 4 drugs in clinically relative concentrations. Sustained suppression in hMSCs was observed following 3 days exposure to the 4 agents. It is concluded that the cisplatin, topotecan, daunorubicin and hydroxyurea alone can induce apoptosis of hMSCs and exert persistent suppressive effect on the proliferation of hMSCs even with short term exposure.

我們曾研究一些白血病常用的化療藥物對人間充質干細胞(MSC)的影響,并發現其獨特的耐藥性。本研究評估一些實體瘤常用的化療藥物如順鉑、拓撲替康、柔紅霉素和可長期使用的口服化療藥物如羥基脲等對人MSC的作用。在體外培養系統中,比較人MSC與NB-4細胞系、人外周血單個核細胞(PBMC)對這些單一化療藥物的敏感性。單一化療藥物作用72小時后,繼續將人MSC在正常培養液培養9天,用XTT方法測定細胞增殖恢復情況。AnnexinV/PI染色后,用流式細胞儀檢測上述4種化療藥物誘導的細胞凋亡。結果表明:人MSC對4種化療藥物均較NB-4細胞耐藥,拓撲替康、順鉑、羥基脲和柔紅霉素對人MSC的IC50分別是其對NB-4細胞的IC50的636倍、24.8倍、20倍以上和2.4倍,但人MSC對拓撲替康、順鉑和柔紅霉素較人PBMNC更敏感,拓撲替康、順鉑和柔紅霉素對人PBMNC的IC50分別是其對人MSC的IC50的27倍以上、1.9倍和1.4倍。4種藥物在臨床濃度都明顯抑制人MSC增殖,去除藥物作用后,這種抑制作用持續存在。上述單一藥物臨床濃度作用于人MSC后48-72小時凋亡細胞增加。結論:順鉑、羥基脲、拓撲替康和柔紅霉素單一藥物均可造成人MSC持續損傷,其機制與細胞凋亡有關。