Thalidomide induces apoptosis in undifferentiated human induced pluripotent stem cells

Abstract

Thalidomide, which was formerly available commercially to control the symptoms of morning sickness, is a strong teratogen that causes fetal abnormalities. However, the mechanism of thalidomide teratogenicity is not fully understood; thalidomide toxicity is not apparent in rodents, and the use of human embryos is ethically and technically untenable. In this study, we designed an experimental system featuring human-induced pluripotent stem cells (hiPSCs) to investigate the effects of thalidomide. These cells exhibit the same characteristics as those of epiblasts originating from implanted fertilized ova, which give rise to the fetus. Therefore, theoretically, thalidomide exposure during hiPSC differentiation is equivalent to that in the human fetus. We examined the effects of thalidomide on undifferentiated hiPSCs and early-differentiated hiPSCs cultured in media containing bone morphogenetic protein-4, which correspond, respectively, to epiblast (future fetus) and trophoblast (future extra-embryonic tissue). We found that only the number of undifferentiated cells was reduced. In undifferentiated cells, application of thalidomide increased the number of apoptotic and dead cells at day 2 but not day 4. Application of thalidomide did not affect the cell cycle. Furthermore, immunostaining and flow cytometric analysis revealed that thalidomide exposure had no effect on the expression of specific markers of undifferentiated and early trophectodermal differentiated cells. These results suggest that the effect of thalidomide was successfully detected in our experimental system and that thalidomide eliminated a subpopulation of undifferentiated hiPSCs. This study may help to elucidate the mechanisms underlying thalidomide teratogenicity and reveal potential strategies for safely prescribing this drug to pregnant women.

VTD in comparison with VCD does not affect stem cell yields with G-CSF only mobilization

“…The average number of CD34+ cells in peripheral blood on collection day was higher in the VCD cohort than in the VTD cohort; however, the difference was not statistically significant. The lower number of CD34+ stem cells can be attributed to the toxic effects of thalidomide on hematopoietic stem cells [27]. To conclude, this study provides further data on VTD safety with respect to stem cell mobilization in comparison with VCD.…”

Thalidomide Inhibits Human iPSC Mesendoderm Differentiation by Modulating CRBN-dependent Degradation of SALL4

“…Human pluripotent stem cells have proven useful in investigating the teratogenicity of thalidomide in vitro. Studies on the effect of thalidomide on human pluripotent stem cells (hPSCs) characterized cytotoxicity in undifferentiated hPSCs 19,20 and hPSC-derived mesoderm 21 and functional effects on hPSC-derived mesendoderm 22 and cardiac mesoderm 20 at concentrations above 100 µM. However, these studies demonstrated effects of thalidomide on PSCs or PSC-derived mesoderm in vitro at concentrations >5-fold in excess of the thalidomide clinical Cmax 7 , which raises concern regarding the relevance of these effects to thalidomide teratogenicity.…”