论文摘要:
Eosinophil peroxidase (EPX) is an abundant heme protein in eosinophils that catalyzes the formation of cytotoxic oxidants implicated in asthma, allergic inflammatory disorders, and cancer. Interestingly, we found that lung cancer tissue also expressed EPX, however the role of altered EPX expression in cancer development remains mostly unknown.
Here, we determined EPX protein expression in clinical samples
analyzed by immunohistochemistry (IHC) analysis in 90 lung adenocarcinoma(AD) using tissue microarrays. For EPX expression, ≤4 was defined as low expression, >4 was high expression. For the first time, we found that EPX overexpression was significantly correlated with lymph node metastasis (P = 0.002) and pathologic-Tumour Nodes Metastasen stage (p-TNM stage) (P = 0.023). There was no significant association between EPX expression and other clinicopathological features. From Kaplan–Meier survival curves, we observed that patients with high expression of EPX protein survived a shorter survival time than patients with low levels (P = 0.017). For further investigation, we analysed the prognostic factors by a multivariate Cox regression model. The results indicated that N stage (HR = 1.672, 95% CI = 1.321–2.418, P = 0.025), p-TNM Stage (HR = 1.678, 95% CI = 1.362–2.734, P = 0.039) and high expression of EPX protein (HR = 2.054, 95% CI = 1.287–3.437, P = 0.017) were observed to an independent prognostic factor for AD patients.
In conclusion, we demonstrated that increased EPX expression could be identified as a poor prognostic biomarker in lung adenocarcinoma.