Oestrogen receptor β in NSCLC - prevalence, proliferative influence, prognostic impact and smoking

In non-small-cell lung carcinoma (NSCLC) there are gender differences. The female gender is associated with more adenocarcinomas (ADCA), among both smokers and non-smokers compared to men. Women with NSCLC have a better prognosis compared to men, regardless of other factors. A possible role for oestrogen receptor (ER) signalling has been proposed. The role for ERβ in NSCLC is still not clear, especially concerning the impact of smoking. In a material of NSCLC (n = 262), ERβ and cyclins A1 and A2 were studied by immunohistochemistry on formalin-fixed paraffin embedded tissue. In 137 of those cases, frozen material was available, on which expression analysis of ESR2 (ERβ) and cyclin A1 were performed. Data were correlated to histology, gender, smoking habits, stage and clinical outcome. ERβ was expressed in 86% of the cases. ERβ was most frequently expressed in Stage I ADCAs, especially in male subjects. A correlation between ERβ expression and cyclins was observed in ADCA, also with a male predominance. ERβ transcripts had a positive prognostic impact in ADCA. ERβ transcripts were increased in NSCLC among smokers compared to non-smokers. In conclusion, our data support a role for ERβ in lung ADCAs, proposing a role for ERβ in lungcarcinogenesis, especially among smokers.