Several serum biomarkers, including the carcinoembryonic antigen (CEA), the cytokeratin 19 fragment (CYFRA 21–1), the tissue polypeptide antigen (TPA), the squamous cell carcinoma antigen (SCC), the cancer antigen 125 (CA-125), the cancer antigen 153 (CA-153), the pro-gastrin-releasing peptide (ProGRP), the cancer antigen 199 (CA-199), tumor-associated glycoprotein 72–3 (TAG-72.3) and neuron-specific-enolase (NSE), have shown usefulness for diagnosis of lung cancers[13][14][15]. Here, ENO2 is linked to lung carcinoma.