Finally, the compilation of the latest data on the role of these peptides in cancer development and the underlying biochemistry indicate that FXYD2 (ATP1G1) and FXYD3 (MAT-8) regulate the activity of the Na, K–ATPase pump and may play a role in regulating cell proliferation, migration, and invasion, key processes in cancer growth and metastasis (Table 1). The gene discussed is FXYD2; the disease is cancer.