Complement Factor H Is Elevated in Bronchoalveolar Lavage Fluid and Sputum from Patients with Lung Cancer

Abstract

Background: Cytologic examination of specimens obtained from the respiratory tract is a lung cancer diagnostic procedure with high specificity but moderate sensitivity. The use of molecular biomarkers may enhance the sensitivity of cytologic examination in the detection of lung cancer.Methods: Complement factor H, a protein secreted by lung cancer cells, was quantified in a series of bronchoalveolar lavage supernatants from lung cancer patients and patients with nonmalignant respiratory diseases. Albumin, total protein content, and hemoglobin were also analyzed. Results were validated in independent sets of bronchoalveolar lavage and sputum supernatants.Results: There was a significantly higher concentration of factor H in bronchoalveolar lavage samples from lung cancer patients. The sensitivity and specificity of the factor H test was 82% and 77%, respectively. These results were validated in an independent set of patients with nearly identical results. Furthermore, 70% and 45% of bronchoalveolar lavage fluids from central and peripheral tumors, respectively, reported as cytologically negative, were classified as positive using this marker. Finally, the test was evaluated in a series of sputum supernatants from lung cancer patients and controls. The sensitivity and specificity of the factor H test in this series was 80% and 88%, respectively.Conclusion: Factor H is elevated in bronchoalveolar lavage and sputum from lung cancer patients. Impact: Measurement of molecular biomarkers, such as complement factor H, may be used in the future as an adjunct to cytology in the diagnosis of malignant pulmonary diseases. Cancer Epidemiol Biomarkers Prev;

Properdin and Factor H: Opposing Players on the Alternative Complement Pathway “See-Saw”

“…For example, factor H has been shown to be elevated in the bronchoalveolar lavage (BAL) and sputum of lung cancer patients (Pio et al, 2010) and has also been described as a marker for bladder cancer (Cheng et al, 2005). Further studies may shed light on the role of properdin in the pathogenesis of AMD as well as its therapeutic involvement.…”

Molecular sputum analysis for the diagnosis of lung cancer

“…Pio et al (2010) demonstrated increased levels of complement factor H in sputum of lung cancer patients, and suggested that large plasma proteins as factor H reflects hyperpermeability in tumour circulation. Factor H quantification may aid in improving sensitivity of sputum cytology for lung cancer diagnosis, but is not proof of malignancy similar to hemoptysis.…”

A New Biomarker Panel in Bronchoalveolar Lavage for an Improved Lung Cancer Diagnosis

“…4 Bronchoscopy can be considered as the primary diagnostic method in patients with suspected pulmonary carcinoma and is also necessary to select the appropriate therapeutic strategy. 5 It is less invasive than other tissue procurement methods, carries a small risk of complications, and has high specificity, although its sensitivity is relatively poor. 5,6 It is expected that approaches that do not require the collection of tumor cells, such as the detection of molecular markers in bronchial fluids, will enhance the sensitivity of cytological examination (30-80% depending on tumor accessibility) 6,7 and improve the diagnostic accuracy.…”