High circulating activin A plasma levels are associated with tumour stage and poor survival in treatment-naive lung squamous cell cancer patients

Objectives

Lung squamous cell carcinoma (LUSC) is associated with a poor prognosis and a lack of specific treatment options. The dysregulation of activin A (ActA) has been reported in various malignancies. Herein, we investigated the diagnostic and prognostic significance of ActA in LUSC.

Materials and methods

ActA concentrations were measured using ELISA in plasma samples of 128 LUSC patients (stage I-IV) and 73 controls, and correlated those values with clinicopathological parameters and survival.

Results

ActA plasma levels were significantly higher in therapy-naive LUSC patients compared to controls (444.1 $\pm$ 310.9 pg/mL vs 338.9 $\pm$ 145.5 pg/mL, p = 0.010). ActA levels significantly correlated with advanced stage as well as with T and N factors. High circulating ActA levels were significantly increased in metastatic disease patients compared to M0 disease. Further, patients with ActA levels above a computationally established optimal cut-off value of 443.0 pg/mL had a significantly worse median overall (OS, 17.63 vs 64.77 months, HR 0.391, 95 % CI 0.200–0.762, p < 0.001) and median disease-/progression-free survival (DFS/PFS; 11.57 vs 30.20 months, HR 0.502, 95 % CI 0.248–1.019, p = 0.020). Multivariate analysis revealed that high ActA levels were an independent prognostic factor for shorter OS (p = 0.001) and DFS/PFS (p = 0.018). A newly developed score combining CRP and ActA levels was also an independent prognostic factor for OS and DFS/PFS.

Conclusion

Measurement of circulating ActA levels may help identify advanced-stage LUSC patients, and this value could serve as a prognostic parameter in LUSC. Thus, ActA may be a novel blood-based biomarker for identifying LUSC patients with distant metastasis.