Furthermore, the levels of ProGRP and NSE in extensive-stage SCLC [ProGRP (227.72±45.41) pg/mL; NSE (136.57±32.87) pg/mL] were notably higher than those in limited-stage SCLC [ProGRP (198.34±64.41) pg/mL; NSE (109.98±31.33) pg/mL] (P<0.05). The gene discussed is ENO2; the disease is small cell lung carcinoma.