Depends on your definition of ECS and of OOP. A Smalltalk user has a very different perspective of OOP to a Java user, for example.
1. Is Entity Component System (ECS) considered a part of OOP or is it a completely different concept?
I can't help but wonder where this question came from, though. Will knowing 'the answer' actually help with anything?!
Again depends on your definitions. You've managed to throw in a third overloaded concept in the form of MVC. This is near-perfect (accidental) trolling
2. Can the Model View Controller design pattern be used with non-OOP coding style, specifically with Entity Component System?
The real answer is: try it, just on paper or a scratch buffer for 10 minutes, using whatever definitions you like for those things.
I'm tempted to say that most MVC systems require something akin to the observer pattern, which I guess you could say means that OOP is a requirement. On the other hand, 'observer' is barely a pattern at all in many functional programming languages, so perhaps not.
I fear these questions are far too vague.
EDIT: the one potentially useful thing I can say is that I'm sure you can implement MVC and and entity component system in pretty much any language, regardless of whether or not it's advertised as 'being OO'. So again, just have a go.