(Wall Street Journal) – Four years ago, a team of researchers led by a heavyweight in the field of microbiology made a stunning claim: Cancers have unique microbial signatures that could one day allow tumors to be diagnosed with a blood test. The discovery captured the attention of the scientific community, as well as investors.

A prestigious journal published the research. More than 600 papers cited the study. At least a dozen groups based new work on its data. And the microbiologists behind the claim launched a startup to capitalize on their findings. Since then, the work has suffered multiple setbacks. (Read More)