PTP1B can act as a tumor promoter in glioblastoma-multiforme, breast, colorectal, non-small cell lung, and ovarian cancer by activating Src and downregulating PTEN, thereby inducing downstream PI3K/Akt and Ras/Raf/MEK/ERK signaling, resulting in increased migration, invasion, and proliferation [273,279]. The gene discussed is PTPN1; the disease is ovarian carcinoma.