Promotion of direct reprogramming by transformation-deficient Myc.
Level 5 - mechanism / opinion, no new human data
Bench and animal research without direct clinical outcomes
PubMed 20660764 · doi:10.1073/pnas.1009374107
What was done
The authors tested whether the promotion of induced pluripotent stem cell (iPSC) reprogramming by Myc can be uncoupled from oncogenic transformation. They evaluated wild-type c-Myc, transformation-deficient c-Myc mutants (W136E and dN2), and L-Myc alongside Oct3/4, Sox2, and Klf4 in human and mouse fibroblasts, assessing reprogramming efficiency in vitro and tumor formation and germline transmission in iPSC-derived chimeric mice.
What was found
The abstract reports no numerical values or statistical comparisons. Qualitatively, L-Myc and the c-Myc mutants (W136E and dN2) promoted human iPSC generation more efficiently and specifically than wild-type c-Myc despite having little transformation activity. In mice, L-Myc promoted germline transmission in iPSC-derived chimeric mice without tumor formation.
Why it matters
This study shows that Myc's reprogramming and transformation functions rely on different functional domains. Using transformation-deficient variants like L-Myc allows efficient iPSC generation while reducing tumorigenic risk.
Limits
This is purely bench in vitro and animal research with no clinical data. The abstract lacks specific sample sizes, quantitative reprogramming efficiency rates, and statistical measures of tumor incidence.
Cited by
- supports The Myc gene is an oncogene, and omitting it from the Yamanaka reprogramming factor cocktail reduces toxicity in reprogramming.