No, it isn't. Here's the paper -
http://www.nature.com/nature/journal/v524/n7564/full/nature1... . Among other things:
> "The core developmental and neuronal gene repertoire of the octopus is broadly similar to that found across invertebrate bilaterians"
> "Using a relaxed molecular clock, we estimate that the octopus and squid lineages diverged ~270 Mya, emphasizing the deep evolutionary history of coleoid cephalopods8"
There is nothing to suggest alien DNA, and the comment from Martin Wells appears to be part of an in-joke to emphasis the unusualness of the octopus.
Moreover, the text at this link is a copy of http://www.ancient-code.com/scientists-conclude-octopus-dna-... , from at least 11 days ago. I prefer links to the primary source over to a copy.