|
Category | Biomarkers | COPD patients | Lung cancer patients |
EBC (compared to healthy volunteers) | EBC (compared to smokers or ex-smokers) | EBC (compared to healthy volunteers) | EBC (compared to specific controls) |
|
Markers of oxidative stress |
Reactive oxygen species | Hydrogen peroxide | ↑ [34, 135–138] | ↑ [34] | ↑ [135] | |
|
Reactive nitrogen species | Nitric oxide | ↑ [139–144] | ↑ [139, 141] | ↑ [140] | ↑ (controls = cancer patients) [142] |
Nitrite | ↑ [145] | ↑ [145] | | ↑ (controls = cancer patients) [142] |
Nitrate | High variability [146] | | | ↓ (controls = cancer patients) [142] |
≈ [141, 147] |
Peroxynitrite | ↑ [148, 149] | ↑ [148, 149] | | |
|
Lipid peroxidation products/eicosanoids (arachidonic acid derivatives) | 8-isoprostane | ↑ [137, 148, 150, 151] | ↑ [34, 148, 150] | | ↑ [135] |
| ≈ (controls = healthy smokers) [152] |
Malondialdehyde | ↑ [138, 153] | ↑ [153] |
↑ [154] | |
≈ [137, 155] | ≈ [137] |
Leukotrienes B4 | ↑ [156–158] | ↑ [159] | | ↑ (controls = patients without pulmonary disease) [156] |
Leukotriene C4 | | | ↑ [160] | |
Leukotriene D4 | | | ↑ [160] | |
Leukotriene E4 | ≈ [158] | | ↑ [160] | |
Prostaglandin E2 | ↑ [158] | | | |
Thromboxane B2 (the stable form of thromboxane A2) | ↓ [158] | | | |
Prostaglandin D2-methoxime | ≈ [158] | | | |
Prostaglandin F2α | ↑ [158] | | | |
|
Cytokines and proteins | Tumour necrosis Factor-α | ≈ [47] | | ↑ [161] | ↑ (controls = smokers without COPD or lung cancer) [152] |
Interleukin-6 | ↑ [162] | |
↑ [163] | |
≈ [47] | | |
Interleukin-8 | ≈ [47, 164] | ≈ [164] | | ↑ (controls = patients without pulmonary diseases) [156] |
Metaloproteinase-9 | | ↑ [134] | | ↑ (controls = patients without pulmonary diseases) [165] |
Vascular endothelial growth factor | | | | ↑ (controls = healthy smokers) [152] |
Endothelin-1 |
↑ [166] | | ↑ [167] | |
↑ [168] |
|
Volatile organic compounds | Alkanes, alkane derivatives, benzene derivatives | ↑ (exhaled ethane) [169] | | ↑ [170, 171] | |
|
Heme breakdown product | Carbon monoxide | ↑ [144] | ↑ [144] | | |
|
pH | | ↓ [164, 172–175] | ≈ [173] | ≈ [172] | |
|
Deoxyribonucleic acid mutations | 3p microsatellite alterations | | | ↑ [176] | |
Tumour suppressor gene P53 mutations | | | ↑ [177] | |
Oncogene KRAS | | | ↑ [178] | |
Epidermal growth factor receptor (EGFR) gene mutations | | | ↑ (in small number of heavy smokers with squamous cell carcinoma) [179] | |
Gene promoter methylation mutations | | | ↑ [180] | |
Mitochondrial DNA mutations | | | | ↑ (controls = smokers, exsmokers without chronic respiratory diseases, respiratory illnesses, or lung cancer) [70] |
|
Viruses | Human papilloma virus | | | | ↑ (controls = patients suspected of lung cancer but with negative cytology) [181] |
|
Markers measuring antioxidant capacity |
Enzymes | Superoxide dismutase | | | | ↑ (controls = patients without pulmonary diseases) [182] |
|
Nonenzymatic antioxidants | Ascorbic acid/vitamin C | | | ↓ (↑ in percentage degradation/oxidation rate) [161] | |
Urate |
× [175] | × [175] | | |
Ferritin | | | | ↑ (controls = patients affected by transudative pleural effusion and without pulmonary diseases) [182] |
Bilirubin | ≈ [175] | ≈ [175] | | |
|