Genes & Cells
A lab mistake may have fingered virus for disease, plus proteins that thwart chemo and more in this week's news
By Science News
Virus off the hook for cancer, fatigue
A virus that has been implicated in causing prostate cancer and chronic fatigue syndrome may be a laboratory contamination problem and not a human pathogen after all. The XMRV virus supposedly causes disease by integrating itself into human DNA. But a new study suggests that previous experiments that found the virus inserted into human genes were faulty due to contamination from a laboratory technique that replicates DNA. The observation, reported February 25 in the online journal Retrovirology by researchers at the Wellcome Trust Sanger Institute and University College London, adds to evidence calling XMRV’s role in human disease into question. —Tina Hesman Saey
Iron RNA
A microRNA involved in hepatitis C infections also helps regulate iron levels in the liver, a new study shows. This microRNA, called miR-122, was already known to regulate cholesterol production. Now, researchers in Germany and Denmark show that the microRNA is needed to keep up iron levels in the liver and blood. Antiviral therapies and cholesterol-lowering treatments have proposed to reduce the amount of miR-122 made in the liver. The new findings, published online March 1 in the Journal of Clinical Investigation, could mean that dropping the microRNA’s levels too low could lead to iron deficiency. —Tina Hesman Saey
Getting to the root of chemo failure
A few cellular proteins may determine when chemotherapy fails. A host of chemo drugs often can’t kill cells missing one protein — called FBW7 — international teams report in two papers appearing in the March 3 Nature. This protein, the teams say, seems to keep certain cellular chemicals in check. These baddies sustain cell life even as outside signals like chemo drugs go for the kill. The chemotherapies stymied by this loss include treatments like Taxol and vincristine, which target a range of cancers, from breast and ovarian tumors to leukemia. Screens for FBW7 in tumors before chemotherapy could help oncologists better tailor their treatments, researchers say. —Daniel Strain