JUN and neoplasm: According to the literature, three signalling pathways associated with TNF-α-induced tumour development are described below: the TNF-α - TNFR1 - signalling complex - MAP3K3/MEKK3/TAK1 - NF-κB pathway, the TNF-α - TNFR1 - signalling complex - MAP3K (ASK1) - JNK or p38 MAPK - AP-1 pathway and the TNF-α - TNFR1 - Ras - Raf - MEK1 - ERK1/2 - AP-1 pathway [31].