RESUMO
OBJECTIVE: To investigate a unique biomarker from the blood plasma and sputum of lung cancer patients based on native fluorescence analysis of body fluids. BACKGROUND: Conventionally, biomarkers indicative of malignancy are identified by biochemical or biophysical processes. Most of the cancer biomarkers, often useful in monitoring disease progression, have sensitivity and specificity in the range of 60%. METHODS: We employed synchronous fluorescence excitation spectroscopy (SFXS) and fluorescence emission spectroscopy for the native fluorescence analysis of blood plasma of 32 normal controls, 32 patients with lung cancer, and 32 patients with other types of cancer. RESULTS: Based on the native fluorescence analysis of blood plasma and sputum, we found that the structural protein elastin, with an excitation peak at 327 nm and an emission peak at 405 nm, is an exclusive biomarker for lung carcinoma with 77% sensitivity and 83% specificity from plasma alone, 92.3% sensitivity and 100% specificity from plasma acetone extract alone, and 66% sensitivity and 100% specificity from sputum alone. CONCLUSION: In this preliminary report with a limited number of lung cancer patients, we have used SFXS of plasma and sputa as the basis for a new technique identifying elastin as an exclusive lung cancer biomarker. This technique has the potential to become a new protocol for rapid and cost-effective screening and diagnosis of lung cancer.
Assuntos
Biomarcadores Tumorais/análise , Elastina/metabolismo , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/patologia , Escarro/química , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Elastina/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Sensibilidade e Especificidade , Espectrometria de Fluorescência/métodosRESUMO
In this preliminary report, benign (n=8) and malignant (n=5) prostate tissues, in vitro, have been taken through autofluorescence spectroscopy. Employing Stokes' shift spectra and fluorescence emission spectra as tools of analysis, we were able to discriminate the two sets of tissues with sensitivity and specificity in excess of 85%. When the excised prostate chips were scanned with a spatial resolution of 1 mm, the epicenter of malignancy also could be delineated.
