Background: Nucleoside triphosphate phosphohydrolase (NTPCR) is a non-specific nucleoside triphosphatase that is slow-acting in vitro. This protein is overexpressed in many tumor tissues, and while it is not essential for the cell, overexpression is cytotoxic. It has been found that cytotoxicity is not related to its triphosphatase activity [taken from NCBI Entrez Gene (Gene ID: 84284)].