The overexpression of PTENP1 in cell lines and in in vivo studies has been shown to regulate cell proliferation, reduce tumour growth, invasion, metastasis and apoptosis [147–151], further solidifying the importance of PTENP1 in regulating the biology of a cell by acting as a tumour suppressor, independent of PTEN. This evidence concerns the gene PTENP1 and neoplasm.