Needs to be said: you do not necessarily need to clear ALL CACHES after editing or adding a news – but it’s for sure the simplest solution
🙂

1. In the TSRef-Section of the Sysfolder/Page containing the news add:
TCEMAIN.clearCacheCmd = all

2. In the TSRef-Section(Options-Tab) of the User add:
options.clearCache.all = 1

And it works – tested on typo3 4.2.8