Tanaka et al. went on to show that when Vγ2Vδ2 T cells were exposed to tumour cells incubated with POM-modified prodrugs 47–49 or their parent acids, the prodrugs stimulated the T cells to secrete TNF-α at lower concentrations than the acids.110 For example, compound 49 was between 80 and 1900 times more potent than its acid form in 22 tumour cell lines. The gene discussed is TNF; the disease is neoplasm.