** Shares of uniform supplier UniFirstUNF.N fall 10.4% to $177 after the bell
** Uniform rental firm Cintas CTAS.O has terminated discussions with UNF for potential takeover
** CTAS says it and UNF were unable to have substantive engagement regarding key transaction terms
** UNF in January had rebuffed takeover proposal from Cintas that valued it at $5.3 billion; said it was confident of its strategy as standalone company
** Up to last close, UNF up 15.5% YTD
(Reporting by Juby Babu in Mexico City)
((Juby.Babu@thomsonreuters.com;))