This is a science story about cancer. It's got nothing to do with Canada except for the fact that the researchers happen to be based there.
It's a Canadian story published in Canada about Canadian researcher. What did you expect, a US flag?
For the US embassy to take part in that, couldn't this seen as a hostile act by the victim country?
Only if said victim country wasn't already the US' bitch.
If they did, I very much doubt they will say anything about it.
Even if they did say anything, would anyone believe them?