Aromatase in human lung carcinoma

Lung cancer is the leading cause of cancer mortality in both women and men worldwide but gender differences exist in their clinical and biological manifestations. In particular, among life time non-smoker, female are far more likely to develop lung carcinoma than male. Recent studies demonstrated that estrogens are synthesized in situ in both male and female lung cancers through aromatase, suggesting that sex steroid may contribute to the pathogenesis and development of lung carcinoma. In addition, human lung carcinomas have been recently demonstrated to be frequently associated with expression of estrogen receptors in both male and female patients and a lower expression of aromatase was reported to be associated with better prognosis. Preclinical studies further demonstrated that aromatase inhibitor (AI) suppressed the lung tumor growth both in vitro and in vivo. These findings all suggest a potential role of intratumoral aromatase in biological behavior of non-small cell lung cancer (NSCLC), the most common form of human lung malignancy. Therefore, AIs may become viable therapeutic options for disease management in NSCLC patients but further studies are definitely required to obtain a better understanding of the potential roles of intratumoral aromatase expression as a predictive biomarker for clinical outcome in these NSCLC patients.

► In situ estrogen (E2) production via aromatase may contribute to human lung carcinoma (LC) development.
► Aromatase is associated with intra-tumoral E2, ERβ expression and tumor stage in LC patients.
► Stimuli from stromal cells of carcinoma tissues may regulate aromatase expression and activity in LC cells via cytokines.
► Aromatase inhibitors (AI) suppressed the LC growth both in vitro and in vivo.
► AIs may be used as one of the therapeutic options for the management of ER positive LC patients.