RESUMEN
Survivin and livin are highly expressed in cancer cells and transformed cells, but show little or no expression in normal differentiated tissues. Although human antibody responses to cancer-associated antigens have been detected, the response to livin has not yet been described in lung cancer patients. We examined prevalence of anti-livin antibodies in such patients with a specific enzyme-linked immunosorbent assay (ELISA) using recombinant protein. Using a cutoff value for positivity determined as the mean absorbance +2S.D. for healthy control samples, 19 of 37 lung cancer patients (51.3%) were positive for anti-livin antibodies. Of 31 samples from the same lung cancer patients, 18 (58.1%) were positive for anti-survivin antibodies. When sera from 31 lung cancer patients were assessed simultaneously by anti-survivin and anti-livin ELISAs. Twenty-one patients (71%) were positive for survivin, livin, or both. Intensity of anti-livin antibody responses did not correlate with intensity of anti-survivin responses. Like anti-survivin antibodies, anti-livin antibodies, thus, can be detected in many lung cancer patients. Testing for both antibodies together may prove useful in detecting lung cancer, but more extensive studies are needed to establish the clinical significance of anti-livin antibodies.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/inmunología , Autoanticuerpos/análisis , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Carcinoma de Células Pequeñas/inmunología , Neoplasias Pulmonares/inmunología , Proteínas Asociadas a Microtúbulos/inmunología , Proteínas de Neoplasias/inmunología , Anticuerpos Antineoplásicos , Formación de Anticuerpos , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Humanos , Proteínas Inhibidoras de la Apoptosis , Neoplasias Pulmonares/fisiopatología , SurvivinRESUMEN
It has been suggested that suppression of apoptosis may contribute to the development and progression of cancer. Anti-apoptotic survivin and livin genes are highly expressed in cancer cells and transformed cells, but show little or no expression in normal differentiated tissues. However, there are no available data concerning livin expression in non-small-cell lung cancer (NSCLC). We therefore measured livin mRNA and survivin mRNA expression in 38 NSCLC cancer samples and 15 paired non-cancerous lung tissue samples using a quantitative reverse transcription-polymerase chain reaction (RT-PCR). While both mRNAs showed higher expression in cancers than non-cancerous tissues (P < 0.001), livin mRNA and survivin mRNA expression did not correlate with one another. When a cut-off value for positivity was set at the mean + S.D. for expression values in non-cancerous tissues, positivity rates for livin mRNA and survivin mRNA expression were 76.3% (29 of 38) and 36.8% (14 of 38) in lung cancers and 6.7% (1 of 15) and 0% (0 of 15), respectively, in paired non-cancerous lung tissue samples. Livin mRNA and survivin mRNA expression in tumors were up-regulated in 23 of 31 (74.2%) early-stage NSCLC patients and 11 of 31 (35.5%), respectively. Expression of both mRNAs in tumors varied independently of tumor histology. These results support the possibility that the livin gene may play a role in NSCLC development and increased expression of livin mRNA may serve as a new target for lung cancer treatment as well as survivin.