ST3GAL4 and lung carcinoma: Further studies concerning the mechanisms involved in ST3GAL4 gene over-expression by TNF in human bronchial explants and in the A549 lung carcinoma cell line have shown the involvement of Extracellular Signal-Regulated kinases (ERK), p38 and Mitogen- and Stress-activated kinases 1/2 (MSK1/2) in the signaling pathways leading to sLex and 6-sulfo-sLex over-expression, while no role of the NF-κB pathway was shown [49].