Background: Hypoxia inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) are key angiogenic regulatory factors. The aim of this study was to identify the most useful prognostic angiogenic factors in advanced nonsmall cell lung cancer (NSCLC) without known driver gene mutations. Methods: Eligible patients were pathologically confirmed to have advanced NSCLC without known driver mutations. All patients were treated with standard first-line chemotherapy ± bevacizumab. Serum concentrations of HIF-1α, VEGF, sVEGFR1, sVEGFR2, and endostatin were measured via enzyme-linked immunosorbent assays (ELISAs) prior to and after two cycles of treatment. Area under the curve (AUC) and optimal cutoff values were calculated by receiver operator characteristic curve (ROC) analyses. The parameters that predicted survival were evaluated by univariate and multivariate Cox proportional hazard analyses. Results: A total of 47 patients were included in this study. HIF-1α levels decreased significantly after treatment in the nonprogressing (partial response/stable disease) patient group (707.94 vs. 355.53 pg/mL, p = 0.002), but increased levels were seen in patients with progressive disease, however, the extent of change did not reach significance (173.70 vs. 416.34 pg/mL, p = 0.078). An HIF-1α ratio of 1.18 was chosen as the best point to predict treatment response through ROC analyses. Via univariate and multivariate analyses, we found that patients with a HIF-1α ratio ≥1.18 after treatment were significantly more likely to have a prolonged progression-free survival (PFS, HR 0.303, 95% CI: 0.153-0.603, p = 0.001) and overall survival (OS, HR 0.436, 95% CI: 0.153-0.603, p = 0.025). Conclusions: We identified the pretreatment to posttreatment HIF-1α ratio as a promising predictor for PFS and OS in NSCLC patients without known driver mutations.
Keywords: angiogenesis; chemotherapy; hypoxia inducible factor-1α; nonsmall cell lung cancer.