Serum Amyloid A Protein: A Potential Biomarker Correlated With Clinical Stage of Lung Cancer

Objective To identify serum diagnosis or progression biomarkers in patients with lung cancer using protein chip profiling analysis. Method Profiling analysis was performed on 450 sera collected from 213 patients with lung cancer, 19 with pneumonia, 16 with pulmonary tuberculosis, 65 with laryngeal carcinoma, 55 with laryngopharyngeal carcinoma patients, and 82 normal individuals. A new strategy was developed to identify the biomarkers on chip by trypsin pre-digestion. Results Profiling analysis demonstrated that an 11.6kDa protein was significandy elevated in lung cancer patients, compared with the control groups （P〈0.001）. The level and percentage of 11.6kDa protein progressively increased with the clinical stages Ⅰ-Ⅳ and were also higher in patients with squamous cell carcinoma than in other subtypes. This biomarker could be decreased after operation or chemotherapy. On the other hand, 11.6kDa protein was also increased in 50% benign diseases of lung and 13% of other cancer controls. After trypsin pre-digestion, a set of new peptide biomarkers was noticed to appear only in the samples containing a 11.6kDa peak. Further identification showed that 2177Da was a fragment of serum amyloid A （SAA, MW 11.6kDa）. Two of the new peaks, 1550Da and 1611Da, were defined from the same protein by database searching. This result was further confirmed by partial purification of 11.6kDa protein and MS analysis. Conclusion SAA is a useful biomarker to monitor the progression of lung cancer and can directly identify some biomarkers on chip.

Metabolic Dysfunction-associated Fatty Liver Disease is Associated with Greater Impairment of Lung Function than Nonalcoholic Fatty Liver Disease

Background and Aims:We compared lung function parameters in nonalcoholic fatty liver disease(NAFLD)and metabolic dysfunction-associated fatty liver disease(MAFLD),and examined the association between lung function parameters and fibrosis severity in MAFLD.Methods:In this cross-sectional study,we randomly recruited 2,543 middle-aged individuals from 25 communities across four cities in China during 2016 and 2020.All participants received a health check-up including measurement of anthropometric parameters,biochemical variables,liver ultrasonography,and spirometry.The severity of liver disease was assessed by the fibrosis(FIB)-4 score.Results:The prevalence of MAFLD was 20.4%(n=519)and that of NAFLD was 18.4%(n=469).After adjusting for age,sex,adiposity measures,smoking status,and significant alco-hol intake,subjects with MAFLD had a significantly lower predicted forced vital capacity(FVC,88.27±17.60%vs.90.82±16.85%,p<0.05)and lower 1 s forced expiratory volume(FEV1,79.89±17.34 vs.83.02±16.66%,p<0.05)than those with NAFLD.MAFLD with an increased FIB-4 score was significantly associated with decreased lung function.For each 1-point increase in FIB-4,FVC was diminished by 0.507(95%CI:-0.840,-0.173,p=0.003),and FEV1 was diminished by 0.439(95%CI:-0.739,-0.140,p=0.004).The results remained unchanged when the statistical analyses was performed separately for men and women.Conclusions:MAFLD was significantly asso-ciated with a greater impairment of lung function param-eters than NAFLD.