Most of the largest companies using Bitcoin are listed on major stock exchanges, but I don't think there's a strong connection between the stock price and Bitcoin markets - except maybe in the case of Overstock.
Patrick M. Byrne, the CEO and chairman of Overstock had said that only 1% of his revenue comes in the form of Bitcoin. And with the recent downward trend in the Bitcoin sector, that share would have been lowered even more. So even for Overstock, the connection is pretty weak. Anyway, let's hope that the situation will change for the better.