It seems completely unlikely to me. Thistle stems die down every year so even if it were theoretically possible to graft to them it would be pointless since by the time the graft took the stem would die anyway. Secondly, Artichoke and Sunflower have much thicker stems than thistles so even if the hypothetical graft worked it would stunt the scion. As for squash - no earthly chance as they are totally unrelated.

But no one says you can't try.