Cancer Cells Unreceptive to Vitamin D
Many human colon cancers may not express receptors for vitamin D, limiting vitamin D’s protective role against colon cancer to the early stages of the disease, report Charles Giardina and colleagues at UConn’s Department of Molecular and Cell Biology and Center for Molecular Medicine in the April 14 issue of Cancer Prevention Research. The researchers observed that adenomas in the colons of mice tended to repress vitamin D receptors, while having elevated Class I histone deacetylases (HDAC). However, HDAC inhibitors may reactivate the vitamin D receptors. They propose that vitamin D could still be protective against colon cancer, but how its receptors are expressed and inhibited in cancer cells needs more examination. Read the article at Cancer Prevention Research.
Rogue X Chromosomes Uncovered in Farmington
Humans only need the genes from one X chromosome to be healthy. The extra one gets trussed up and shut down in the earliest stages of development. But female human embryonic stem cells growing in the lab sometimes reactivate their second X. They express extra genes, fouling up experiments and scuttling potential therapies. Now, researchers including UConn’s Marc Lalande and a team from Paris Diderot University have found a marker, and potentially a mechanism, for how the extra X reactivates – and they have an idea on how to prevent it. They describe their findings in the May 7 issue of Cell Stem Cell.
Friends are Unreliable Sources for Drinking Studies
In recent years, researchers have turned to friends of people in alcohol studies to verify what the subjects report about their drinking habits. People in the same social situations are sought out, in part, because of the inherent impairment caused by alcohol. But according to a UConn study published in Addictive Behaviors, friends don’t seem to provide any new information. In fact, they typically underreport what their acquaintances consume. The finding supports the so-called “protective effect” of friends described in other research. A growing availability of other evidence – hair and fingernail samples, for example – may provide better strategy for corroborating the amount of alcohol study subjects consume, says author Michael Fendrich, associate dean of the School of Social Work.
She Smells Him, She Smells Him Not
Mice rely on their noses to help them navigate the world. But high levels of progesterone “blind” receptors in the noses of female mice to male pheromones, UConn Health’s John Peluso and other colleagues, led by Dr. Lisa Stowers of The Scripps Research Institute, report in the June 4 issue of Cell. Female mice have high levels of progesterone during the infertile phase of their reproductive cycles, and tend to be indifferent or even aggressive toward males. But during the fertile phase, progesterone levels drop and estrogen rises, and their nasal receptors again respond to male pheromones, the researchers found. Female mice in their fertile phase are friendly and sexually receptive towards males – perhaps because they can smell them.