NPR3 and adenoma: Alcian blue staining for mucin-producing cells was negative, as was qPCR and immunohistochemical studies for Muc-2, Sucrase isomaltase, Lactase phlorzin hydrolase, Carbonic anhydrase I, alkaline phosphatase, Down-regulated in adenoma (S26A3/DRA), Na-H Exchanger 2 (NHE2), and Guanyl Cyclase-C (data not shown).