5hmC (red staining) is lost after mouse skin cells persist in culture.S. PENNINGS LABIn vitro experimentation is a necessary, albeit imperfect, proxy for the study of live organisms, one that scientists have continually tried to optimize to best mimic the real deal. In Genome Biology today (February 3), researchers reported yet another gap between culture and critter: an epigenetic mark, 5-hydroxymethylcytosine (5hmC), all but disappears from certain mouse cells a few days after they’re transferred to a dish.
“This paper adds substantial fuel to the fire of concern about using cultured cells to study phenotypes associated with cancer in vivo (such as drug resistance),” Michael Gottesman, chief of the Lab of Cell Biology at the National Cancer Institute’s Center for Cancer Research, told The Scientist in an e-mail. “Obviously, these studies are done using mouse embryo fibroblasts and not human cancer cells, but the changes in 5hmC levels are so dramatic and so rapid that they cannot be ignored.”
5hmC is the result of Tet enzymes adding a hydroxyl group to 5-methylcytosine, or 5mC, which is a cytosine with a methyl group attached.
Following up on their observation that 5hmC levels were low to undetectable in various human cancer cell lines, Richard Meehan ...
