We considered that culturing of HFSCs with M-CnT for a long term might inhibit their potential for differentiation into mature follicle cells as well as their HF-inducing ability by epigenetic regulation of transcriptional factors, such as Lhx2 and Sox9, because up-regulation of some transcription factor genes related to an undifferentiated state is known to be involved in establishment of induced pluripotent stem cells and directly reprogrammed cells39–42. This evidence concerns the gene LHX2 and hydrops fetalis.