Serum messenger RNA (mRNA) is an emerging prognostic tool for noninvasive malignant disease prognosis, and to study serum mRNA may have importance in the prognosis and detection of disease. This study aimed to evaluate the possible prognostic role of serum ERBB3 and ERBB4 mRNA expressions in lung adenocarcinoma patients. One hundred newly diagnosed lung adenocarcinoma patients and 100 age- and sex-matched healthy controls were included. Expression was analysed by quantitative real-time PCR and overall survival was analysed by Kaplan-Meier analysis. Serum ERBB3 and ERBB4 mRNA expressions was found to be significantly associated with distant metastases and TNM stages. It was observed that patients with distant metastases had 4.8- and 3.4-fold high ERBB3 and ERBB4 expression in contrast to patients without distant metastases, respectively. It was also found that ERBB3 and ERBB4 mRNA expression was 7.7-fold and 6.7-fold high in TNM stage IV compared to TNM stage I, respectively. Significantly, 2.6-fold increased serum ERBB4 mRNA expression was found in patients with pleural effusion compared to patients without pleural effusion (p = 0.005). Lung adenocarcinoma patients with ≤8- and >8-fold increased serum ERBB3 mRNA expression had 10.0 and 5.5 months of overall median survival while serum ERBB4 mRNA with ≤10- and >10-fold increased expression showed 11.4 and 5.0 months overall median survival, respectively. ERBB3 and ERBB4 together also found to be significantly associated with poor overall median survival. Patients with ≤8 + ≤10- and >8 + >10-fold expression showed 11.3 vs 4.8 months of overall median survival, respectively. In conclusion, serum ERBB3 and ERBB4 mRNA expressions may be a prognostic marker and monitoring of serum ERBB3 and ERBB4 mRNA can be one of the predictive factors for metastases and poor overall survival of lung adenocarcinoma patients.
Keywords: Lung adenocarcinoma; Overall survival; Serum ERBB3 and ERBB4 mRNA.