Effect of umbilical cord mesenchymal stem cells on the growth of human breast cancer MCF-7 xenograft in a nude mouse

doi:10.3969/j.issn.2095-4344.2015.19.006

Abstract：BACKGROUND:Mesenchymal stem cels reveal notable therapeutic effects on diabetes, graft-versus-host disease and autoimmune diseases after alogeneic hematopoietic stem cel transplantation. Clinical safety is crucial for the clinical application of mesenchymal stem cels, and whether transplated mesenchymal stem cels can promote tumor growth in vivo or not is an important manifestation; however, fewer studies have been reported on this field. OBJECTIVE: To observe the effect of umbilical cord mesenchymal stem cels on growth of human breast cancer MCF-7 xenograft in a nude mousein vivo. METHODS:Eight BALB/c nude mice were randomly selected as controls, and nude mice with human breast cancer MCF-7 xenograft were randomly divided into four groups with eight mice in each group: model control group, low-dose group, middle-dose group and high-dose group. Three different doses of umbilical cord mesenchymal stem cels (4×104, 2×105 and 1×106/mice) were given twice in the latter three groups, respectively, with an interval of 2 weeks. Healthy nude mice and MCF-7 tumor-burdened mice without transplantation were given normal saline. The experimental observation period was 6 weeks. RESULTS AND CONCLUSION:The tumor size exhibited an increasing trend in the model control group. Umbilical cord mesenchymal stem cels could inhibit tumor growth, but there was no difference among different groups. Histopathological analysis showed that one mouse had lung metastases in either high-dose or middle dose-group. These findings indicate that umbilical cord mesenchymal stem cels cannot promote the tumor growth in a MCF-7 xenograft nude mouse, but they can accelerate the tumor metastases.