RESUMEN
<p><b>OBJECTIVE</b>To explore the biomarkers of early diagnosis in patients with polycyclic aromatic hydrocarbons (PAHs)-related lung cancer for the application to detection of occupational lung cancer or related lung cancer.</p><p><b>METHODS</b>Western dot blotting was used to explore the expression of ras, p53 and heat stress protein 70 (HSP70) in 29 patients with PAHs-related lung cancer (LC), and 28 patients with non-cancerous pulmonary disease, and 30 healthy controls.</p><p><b>RESULTS</b>The positive detection rates of P21, P53, and HSP70 in LC group (58.62%, 34.48%, 41.38% respectively) were higher than those in non-cancerous pulmonary disease group (14.29%, 7.14%, 10.71% respectively, P < 0.01). The sensitivity of P21, P53 and HSP70 were 58.62%, 34.48% and 41.38% respectively, negative predictive value (NPV) were 68.42%, 78.05% and 63.04% respectively. The co-detection of the three proteins mentioned above produced a sensitivity of 82.76% with a NPV of 78.26% (P < 0.05). Of 18 cases of LC with negative cytology, 13 (72.22%) were found HSP21, P53 or HSP70 positive.</p><p><b>CONCLUSIONS</b>Co-detection of the P21, P53, and HSP70 may be used as the screening marker for diagnosis of PAHs-related lung cancer, and may supplement the diagnostic value of conventional cytology.</p>