CDKN2B upregulation prevents teratoma formation in multipotent fibromodulin-reprogrammed cells
Zhong Zheng, … , Kang Ting, Chia Soo
Zhong Zheng, … , Kang Ting, Chia Soo
Published July 15, 2019
Citation Information: J Clin Invest. 2019;129(8):3236-3251. https://doi.org/10.1172/JCI125015.
View: Text | PDF
Research Article Cell biology

CDKN2B upregulation prevents teratoma formation in multipotent fibromodulin-reprogrammed cells

Abstract

Tumorigenicity is a well-documented risk to overcome for pluripotent or multipotent cell applications in regenerative medicine. To address the emerging demand for safe cell sources in tissue regeneration, we established a novel, protein-based reprogramming method that does not require genome integration or oncogene activation to yield multipotent fibromodulin (FMOD)-reprogrammed (FReP) cells from dermal fibroblasts. When compared with induced pluripotent stem cells (iPSCs), FReP cells exhibited a superior capability for bone and skeletal muscle regeneration with markedly less tumorigenic risk. Moreover, we showed that the decreased tumorigenicity of FReP cells was directly related to an upregulation of cyclin-dependent kinase inhibitor 2B (CDKN2B) expression during the FMOD reprogramming process. Indeed, sustained suppression of CDKN2B resulted in tumorigenic, pluripotent FReP cells that formed teratomas in vivo that were indistinguishable from iPSC-derived teratomas. These results highlight the pivotal role of CDKN2B in cell fate determination and tumorigenic regulation and reveal an alternative pluripotent/multipotent cell reprogramming strategy that solely uses FMOD protein.

Authors

Zhong Zheng, Chenshuang Li, Pin Ha, Grace X. Chang, Pu Yang, Xinli Zhang, Jong Kil Kim, Wenlu Jiang, Xiaoxiao Pang, Emily A. Berthiaume, Zane Mills, Christos S. Haveles, Eric Chen, Kang Ting, Chia Soo

×

Figure 4

Intratesticular implantation of FReP cells does not lead to tumorigenesis in Fox Chase SCID Beige mouse testes.

Options: View larger image (or click on image) Download as PowerPoint
Intratesticular implantation of FReP cells does not lead to tumorigenesi...
(A) Gross appearance and histological evaluation (H&E staining) of adult Fox Chase SCID Beige mouse testes that were intratesticularly implanted with 1 × 106 cells were documented at 4 months after implantation. All implanted mice testes are shown in Supplemental Figure 3 (10 mice per group). In addition, by tracking of human mitochondria in vivo, significant survival of the implanted human cells was only observed in the BJ-iPSC group, in which teratoma formation was also detected. Scale bars: 5 mm (black), 1 mm (blue), or 100 μm (yellow). (B) The expressions of multiple proto-oncogenes were compared between parental BJ fibroblasts, retrovirus-mediated BJ-iPSCs, FReP-basal cells, and FReP cells. ERBB3, erb-b2 receptor tyrosine kinase 3; DEK, DEK proto-oncogene; DNMT3B, DNA methyltransferase 3β; FLT3, fms-related tyrosine kinase 3; FOXO1, forkhead box 1; LIN28, lin-28 homolog A; KIT, KIT proto-oncogene receptor tyrosine kinase; POU2F1, POU class 2 homeobox 1; TDGF1, teratocarcinoma-derived growth factor 1. Data are normalized to those of the BJ fibroblasts and presented as mean ± SD. **P < 0.005 (analyzed by 1-way ANOVA and 1-tailed 2-sample t tests); n = 3 independent experiments performed in duplicate. Dashed lines indicate the gene expression levels of BJ fibroblasts; black asterisks indicate significance in comparison with BJ fibroblasts; blue asterisks indicate significance in comparison with FReP cells.