Serum antibodies to retinal antigens in lung cancer and sarcoidosis.
OBJECTIVE
Autoantibodies to various neuronal proteins frequently accompany lung cancer and their appearance may precede cancer symptoms. In this study we examined which retinal antigens (RAs) are recognized by sera of patients with lung cancer and whether the occurrence of serum antibodies to particular RAs is characteristic for cancer in comparison with a noncancer lung disease.


METHODS
Sera of 72 patients with non-small-cell lung cancer (NSCLC), 29 with small-cell lung cancer (SCLC), 27 with sarcoidosis (S), and sera of 32 healthy donors were examined in immunoblotting using retinal extracts and purified RAs as antigens.


RESULTS
69.0% of SCLC, 45.8% of NSCLC, and 44.4% of S sera displayed anti-RAs reactivity. Significantly less (p < 0.05; chi(2) test) percent of healthy control sera reacted with RAs. Lung cancer sera recognized mainly 46-, 56-, and 36-kD and to a smaller extent also 96-, 72-, 43-, and 26-kD proteins. Most of them were recognized with about 2-fold lower frequencies by S and control sera. Only lung cancer sera contained very high-titer antibodies to 46- and 26-kD RAs, identified as alpha-enolase and recoverin, respectively.


CONCLUSIONS
Antibodies to RAs occur more frequently and in higher titers in lung cancer (especially SCLC) than in sarcoidosis or control sera. Although antibodies to retinal alpha-enolase, recoverin and other RAs are present mainly or exclusively in lung cancer sera, none of them seems to be a specific marker of a particular disease.
Jankowska
R
R
Department of Pulmonology, Wroclaw Medical University, Wrocław, Poland.
Witkowska
D
D
Porebska
I
I
Kuropatwa
M
M
Kurowska
E
E
Gorczyca
W A
WA
D000328:Adult; D000368:Aged; D000941:Antigens / Q000276:immunology; D000951:Antigens, Neoplasm / Q000276:immunology; D001323:Autoantibodies / Q000276:immunology*; D014408:Biomarkers, Tumor / Q000032:analysis*; D002135:Calcium-Binding Proteins / Q000276:immunology; D002289:Carcinoma, Non-Small-Cell Lung / Q000276:immunology*; D004268:DNA-Binding Proteins / Q000276:immunology; D004591:Electrophoresis, Polyacrylamide Gel; D005136:Eye Proteins / Q000276:immunology; D005260:Female; D016147:Genes, Tumor Suppressor; D006801:Humans; D008074:Lipoproteins / Q000276:immunology; D008175:Lung Neoplasms / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D024101:Mitochondrial Proteins; D009687:Nuclear Proteins / Q000276:immunology; D010444:Peptide Elongation Factor Tu / Q000276:immunology; D010751:Phosphopyruvate Hydratase / Q000276:immunology; D051603:Recoverin; D012160:Retina / Q000276:immunology*; D012507:Sarcoidosis / Q000276:immunology*; D000072160:Tumor Protein p73; D025521:Tumor Suppressor Proteins / Q000276:immunology
D000941:Antigens; D000951:Antigens, Neoplasm; D001323:Autoantibodies; D014408:Biomarkers, Tumor; D002135:Calcium-Binding Proteins; D004268:DNA-Binding Proteins; D005136:Eye Proteins; D008074:Lipoproteins; D024101:Mitochondrial Proteins; D009687:Nuclear Proteins; C496731:RCVRN protein, human; C091648:TUFM protein, human; D000072160:Tumor Protein p73; D025521:Tumor Suppressor Proteins; D051603:Recoverin; D010444:Peptide Elongation Factor Tu; C095157:ENO1 protein, human; D010751:Phosphopyruvate Hydratase