[Updates to make clear that ScienceDaily recycles press releases and does not do original reporting.]
In February, 2012, Gary Langreth and colleagues at Case Western Reserve University in Cleveland reported that a cancer drug called bexarotene, or Targretin, could produce dramatic improvements in mice with a condition resembling Alzheimer's disease. The most notable finding was that the drug produced a 25 percent drop in amyloid beta peptide, a substance that damages nerve cells in the brain and is associated with Alzheimer's disease.
The mice also resumed some normal behavior, such as building nests, a skill they had lost. "We have successfully reversed all of the known pathological features and behavioral deficits found in mouse models of Alzheimer's disease," Landreth told Gary Stix at Scientific American. "Never before has anyone observed clearance of amyloid plaques with such speed in mouse models."
Other researchers rushed to confirm the findings, which promised to be a major advance in Alzheimer's treatment, if they could withstand the scrutiny of other labs.
Now the results are in, and the answer is…confused. Some stories say the drug was effective, and some say it wasn't, as Gary Schwitzer at HealthNewsReview has noted. The mice, he suggests, are as confused by the findings as they are by their Alzheimer's disease.
Schwitzer links to a few stories on either side of the question, such as this from Julie Steenhuysen at Reuters: "Labs reject dramatic findings on cancer drug in Alzheimer’s mice," and this, from the Pittsburgh Tribune-Review: "Pitt researchers verify cancer drug improves Alzheimer’s symptoms in mice."
But my favorite examples come from ScienceDaily, which recycles press releases as if they were news stories and reports the story both ways. One story, based on a University of Pittsburgh press release, says, "Drug Reverses Alzheimer's Disease Deficits in Mice." The other–at the same site, remember, but based on a University of Chicago release–says, "Multiple Research Teams Unable to Confirm High-Profile Alzheimer's Study."
Apparently what's happening here is that the drug did a couple of things. According to Landreth's original study a year ago, it eased some of the mice's memory deficits, and cleared some of the amyloid from their brains. The Pittsburgh team confirmed the easing of the deficits, but did not find that the drug cleared amyloid. The report from the team including the University of Chicago failed to find clearance of amyloid, and so judged the study a failure.
The stories don't actually conflict, but only the most determined readers willing to look up multiple versions of the story would be likely to figure this out.
If you're still confused, ScienceDaily has help. A day after it published the two conflicting reports, it followed up with a third story–a tiebreaker!–headlined "New Insights Contradict Promising Alzheimer's Research."
Unfortunately, this seems to be a promising drug, or at least one worth further study. The confused and incomplete reporting has done a disservice to Alzheimer's patients who might one day benefit from it. And to their families, and to all the rest of us, who simply want to know what's going on.