Prognostic impact of β2 adrenergic receptor expression in surgically resected pulmonary pleomorphic carcinoma

Background/Aim: The β2-adrenergic receptor (β2AR) is highly expressed in various human cancers and has been linked to tumor growth and metastases. Although β2AR is considered a novel therapeutic target of human neoplasms, the clinicopathological significance of β2AR expression in patients with pulmonary pleomorphic carcinoma (PPC) remains unclear. The aim of this study was to clarify the prognostic impact of β2AR in PPC. Patients and Methods: One hundred and five Japanese patients with surgically resected PPC were included in the study. The expression levels of β2AR were assessed by immunohistochemistry in specimens from the resected tumors, and their association with patient survival, as well as with tumor characteristics was investigated. Results: β2AR was highly expressed in 63% of all patients, irrespective of adenocarcinoma components present. The β2AR expression was significantly associated with lymph node metastasis, lymphatic permeation and tumor cell proliferation in PPC patients with early-stage disease (stage I or II). A high β2AR expression was identified as a significant predictor of worse prognosis for PPC patients during early stages of the disease. Multivariate analysis confirmed that β2AR expression was an independent factor for predicting the overall survival of PPC patients. Conclusion: β2AR can serve as a significant predictor of tumor aggressiveness and poor survival for PPC patients, especially those with early-stage disease.