Clinical value of serum Ape1/Ref-1 combined with TGF-β1 monitoring in predicting the occurrence of radiation pneumonitis (RP) in non-small cell lung cancer patients

BACKGROUND The aim of the present study was to explore the predictive value of serum apurinic/apyrimidinic endonuclease 1/redox factor-1 (Ape1/Ref-1) combined with transforming growth factor β1 (TGF-β1) levels in the occurrence of radiation pneumonitis (RP) in patients with non-small cell lung cancer (NSCLS). METHODS Eighty-one patients with NSCLS who were admitted from August 2017 to July 2019 were enrolled in the present study. All patients were treated with concurrent radiotherapy and chemotherapy. Serum Ape1/Ref-1 and TGF-β1 levels were measured before treatment and 12 weeks after treatment. Patients with radiation-induced lung injury were assessed and divided into the RP group (lung injury ≥2) and non-RP (NRP) group (grade <2). The levels of serum Ape1/Ref-1 and TGF-β1 before and after treatment between the 2 groups were compared. The relationship between clinical characteristics, serum Ape1/Ref-1, TGF-β1 levels, and the occurrence of RP were then analyzed, and the relationship between serum Ape1/Ref-1, TGF-β1 levels, and their predictive value for the occurrence of RP was also assessed. RESULTS The incidence of RP in 81 patients was 30.86%. After treatment, the serum Ape1/Ref-1 and TGF-β1 levels of the 2 groups were significantly higher than those before treatment (P<0.05). Furthermore, after treatment, the levels of serum Ape1/Ref-1 and TGF-β1 in the RP group were significantly higher than those of the NRP group (P<0.05). Multivariate logistic regression analysis showed that V20, Ape1/Ref-1, and TGF-β1 were associated with the occurrence of RP (P<0.05). The levels of serum Ape1/Ref-1 were positively correlated with TGF-β1 (r=0.734, P<0.05). Finally, the area under the curve of RP occurrence, which was predicted by the levels of serum Ape1/Ref-1, TGF-β1, and the combination of both were 0.779, 0.69, and 0.842, respectively. CONCLUSIONS The occurrence of RP in NSCLS patients is closely related to the levels of serum Ape1/Ref-1 and TGF-β1, and the combination of both has important predictive values for the occurrence of RP.