|WikiProject Chemicals||(Rated Stub-class)|
Phloretin is not Naringenin chalcone
Phloretin and Naringenin chalcone are two different chemicals.
Naringenin chalcone: http://www.agrool.gr/files/naringenin%20chalcone.jpg
Naringenin chalcone has a doublebond.
Sorry for my bad english.
Phloretin is a reversible inhibitor. Phloretin inhibits urea transport in toads, with increased Phloretin concentration urea transport is inhibited, however once Phloretin is removed the urea is able to move. 
Phloretin also inhibits glucose transport and Protein Kinase C, which induces apoptosis (cell death). 
Phloretin induces cell cycle arrest and inhibits cell proliferation. Phloretin can be used as a therapeutic effect for tumours as seen in Glioblastoma.