Following a quantitative analysis of the above peptides, we found that there were 7 peptides with the coefficient of variation (CV) less than 30% and among them the peptide of QGAKIPKPEASFSPR from ITIH4 was down-regulated and the peptide of CDDYRLC from MGP was up-regulated in NSCLC group. The gene discussed is MGP; the disease is non-small cell lung carcinoma.