TNF and neoplasm: Our results show that very low amounts of HMB-PP are able to mimic the major effects of saturating ligation of the TCRγδ/CD3 complex, including the very rapid activation of MEK/Erk and PI-3K/Akt pathways to set up a transcriptional program, further enhanced by IL-2 signaling, that upregulates crucial target genes such as IFNγ or TNFα and endows cells with potent anti-tumor capacity.