Figure 1.

Estrogen pathway in lung carcinogenesis and its relevance on therapy. Through non-genomic and genomic pathways, estrogen promotes cell proliferation, tumor growth, angiogenesis, cell migration, immunosuppressive responses, and tumor progression since tumor cells overexpressed ERβ. ARO expression maintains elevated E2 levels. The functional relationship between EGFR/EGF and E2/ER pathways sustain the E2 production through ARO expression and the EGFR activation in EGF absence. Preclinical studies have shown antiestrogen treatment efficacy, and in clinical trials, antiestrogen drugs have improved the clinical benefits of TKI and chemotherapy.