First thing would be to de-correlate this 'news blockchain' entirely from any sort of 'coin', 'token', whatever 'currency' thing — a blockchain is a distributed database, period, 'crypto-coins' being just one application for this storage.

There are several ways to do it then but a standard would likely emerge, as in: "we <publisher> commit to mirror-publish our content to ThePressChain."

You'd likely store only text (say the raw html) on the blockchain though, so using links for pictures etc; which implies your CDN is archived publicly for later retrieval (I suppose a deal with archive.org or equivalent is in order to bolster such a paradigm).