Not directly, no. To begin with, the Kindle and the Sony readers use completely different e-book formats... one cannot read the formats of the other.
In some cases, it might be possible to convert the Kindle documents (essentially an altered Mobipocket format) into the Sony format (LRF). But you might have to crack any existing DRM on the Kindle document first, then you'd have to input the text into software that would convert it into LRF... possibly through an interim step, like pasting the text into a word processing program first, then into your LFR creation software...
...or, to put it another way, it's probably not worth the trouble.