FXYD domain-containing ion transport regulator 5 (FXYD5) is a cancer-associated cell membrane glycoprotein which is a part of the FXYD family. FXYD5 is engaged in down-regulation of E-cadherin, which takes part in tumor development and metastasis and results in reduced cell adhesion.FXYD is found in spleen, lung, skeletal muscle, and testis tissue, and maps to human chromosome 19q13.2.