I used to be a cancer researcher. "used to" mainly because of people like this cancer researcher you showed, who often have no clue (or have archaic preconceived notions) about a lot of things that affect their experiments such as this. The vast majority of them cannot tell the difference between one and two tailed t tests, and have little regard to the degree to which the artificiality of their experimental conditions screws up their results.

This is precisely the reason "50% of cancer research is irreproducible" is a conservative statement.