PTEN and neoplasm: Inhibitory LILRB1-5 signal through their immunoreceptor tyrosine-based inhibitory motif (ITIM) in their intracellular domain and recruit the phosphatase protein tyrosine phosphatase (PTPN), which can directly regulate the development, drug resistance and recurrence of cancer, and when PTPN is missing, it can induce the resistance of CD 8 T cells to the inhibitory effect of TGFβ, which can improve the sensitivity of tumor treatment (70–72).