<prompt> Regan enzyme is an isoenzyme of ?LDHCreatinine kinaseAcid phosphataseAlkaline phosphatase  <response>: Ans. is d i.e., Alkaline phosphataseRegan enzyme isoenzyme is the isoenzyme of alkaline phosphatase.It arises from placenta know as carcinoplacental enzyme.It is elevated in about 15 fo cases of carcinoma of lung, liver and gut. 