TGFA and neoplasm: Researchers employed the ΔppGpp Salmonella mutant to deliver a recombinant drug TGFα-PE38, an immunotoxin comprising a modified Pseudomonas exotoxin A (PE38) conjugated with TGFα, and investigated the process through which it undermined the tumor by inducing the expression of pro-inflammatory cytokines from macrophages and neutrophils, such as IL-1β and TNFα [46,50].