SHH and neoplasm: As IL-1β and TNF-α are two prominent proinflammatory cytokines excreted by necrotic tumour cells, some evidence indicated that proinflammatory cytokines of TNF-α/IL-1β could activate Hh pathway with a profile of the upregulated expression of Gli1 and Shh expression, thus they are able to directly reflect the degree of tumour necrosis through the stimulation of Hh transcription [41].