PRL administration in animal models increases metastasis, while loss of the PRL receptor (PRLR) prevents the progression of neoplasia into invasive carcinoma(Hammer & Diakonova, 2016; Liby, Neltner, Mohamet, Menchen, & Ben-Jonathan, 2003; Oakes et al., 2007). This evidence concerns the gene PRLR and neoplasm.