TLR4 and neoplasm: More specifically, the vaccine included two molecules: an mRNA encoding for MAGE-A1, an immunogenic protein that is highly expressed in lung cancer and is involved in tumor proliferation, invasion, and metastasis [42], as well as monophosphoryl lipid A (mPLA), a toll-like receptor 4 (TLR4) agonist, which can be inserted into the hydrophobic layer of liposomes.