Yesterday’s post on B-cells and breast cancer has generated a lot of debate, some justified and some not. Before joining the debate you need to know how the mind works. There is a rapid, or fast, intuitive decision making system called system 1 and a slow more rational decision making system called system 2. If you are interested in reading about the way we think I would suggest you read ‘Thinking, Fast and Slow’, the best-selling book by Nobel laureate Daniel Kahneman. Just reading the introductory chapter of the book will be enough to give you the gist of system 1 and system 2 thinking.
Then there is ‘reverse causation’, which is likely to be the best explanation. In other words benign breast lesions that don’t recruit B-cells are different biologically to those that do and are more likely to become malignant. The B-cells may simply be innocent bystanders and their presence or absence makes no difference in the long-term. Despite this there is the possibility that the findings are causal, i.e. B-cells are involved in preventing breast cancer.
Baker & Dolgin. Cancer reproducibility project releases first results. Nature 18 January 2017.
….. The Reproducibility Project: Cancer Biology launched in 2013 as an ambitious effort to scrutinize key findings in 50 cancer papers published in Nature, Science, Cell and other high-impact journals. It aims to determine what fraction of influential cancer biology studies are probably sound — a pressing question for the field. In 2012, researchers at the biotechnology firm Amgen in Thousand Oaks, California, announced that they had failed to replicate 47 of 53 landmark cancer papers. That was widely reported, but Amgen has not identified the studies involved.
….. The reproducibility project, by contrast, makes all its findings open — hence Ruoslahti’s discomfort. Two years in, the project downsized to 29 papers, citing budget constraints among other factors: the Laura and John Arnold Foundation in Houston, Texas, which funds the project, has committed close to US$2 million for it. Full results should appear by the end of the year. But seven of the replication studies are now complete, and eLife is publishing five fully analysed efforts on 19 January.
…… These five paint a muddy picture (see ‘Muddy waters’). Although the attempt to replicate Ruoslahti’s results failed, two of the other attempts “substantially reproduced” research findings — although not all experiments met thresholds of statistical significance, says Sean Morrison, a senior editor at eLife. The remaining two yielded “uninterpretable results”, he says: because of problems with these efforts, no clear comparison can be made with the original work.