MALAT1 and gastric cancer: CC-chemokine ligand 21 (CCL21), which was remarkably upregulated in both gastric cancer and leukemia, induces the overexpression of oncogenic lncRNA MALAT1 which activates the mTOR signaling pathway, thereafter expediting the EMT process to enhance the migratory and invasive capabilities of gastric cancer cells and cutaneous lymphoma cells [83, 84].