In vitro study on role of Hsp70 expression in DNA damage of human embryonic lung cells exposed to Benzoapyrene / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>Benzo[a]pyrene (B[a]P), a ubiquitous environmental pollutant, is a potent procarcinogen and mutagen that can elicit tumors, leading to malignancy. Heat shock proteins (Hsp) have been shown to protect cells against damages caused by various stresses including exposure to numerous chemicals. Whether Hsps, or more specifically Hsp70, are involved in repair of B[a]P-induced DNA damage is currently unknown.</p><p><b>METHODS</b>We assessed the potential role of the inducible form of Hsp70 in B[a]P-induced DNA damage of human embryonic lung (HEL) cells using immunoblot and the comet assay (i.e., the single cell gel electrophoresis assay).</p><p><b>RESULTS</b>Exposure to B[a]P induced a dose-dependent decrease in the level of Hsp70, but a dose-dependent +-increase in DNA damage both in untreated (control) HEL cells and in cells preconditioned by a heat treatment. Heat preconditioning prior to B[a]P exposure potentiated the effect of B[a]P at a low dose (10 micromol/L), but appeared to be protective at higher doses. There was a negative correlation between Hsp70 level and DNA damage in the non-preheated as well as in the preconditioned cells.</p><p><b>CONCLUSION</b>These data suggest that exposure of HEL cells to B[a]P may induce a dose-dependent reduction in the levels of the inducible Hsp70. The detailed mechanisms for the reduction of Hsp70 levels by B[a]P and the role of Hsp70 in DNA damage under different concentrations of B[a]P remains to be determined.</p>

Co-detection of P21, P53 and HSP70 and their possible role in diagnosis of polycyclic aromatic hydrocarbons (PAHs)-related lung cancer / 中华劳动卫生职业病杂志

<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>