TNF and neoplasm: These results are in line with our previous findings on the impact of hypoxia and L‐mimosine on angiopoietin‐like 4 in dental pulp‐derived cells.36 Similar findings have been reported for cell lines of non‐oral origin including tumor cells, adipocytes, and renal cells.10, 37 Yet, it seems that the response also depends on the differentiation status of the cells.9, 38 The fact that neither LPS nor IL‐1β, or TNFα can modulate angiopoietin‐like 4 suggests that angiopoietin‐like 4 production in PDLF is mainly regulated by hypoxia‐induced signaling.