Lung cancer is the most common cause of cancer-related death worldwide in both sexes. Evidence suggests the role of genetic factors in lung cancer. Studying of such factors can help understand the cancer prognosis. Overexpression of the human epidermal growth factor receptor-2 (HER2/neu) protein is considered an important prognostic factor in breast cancer, but its role has not been confirmed in lung cancer. Therefore, the present study aimed to investigate the role of its expression in patients with lung cancer.
In this cross-sectional study, patients aged >18 years who were referred to Afzalipoor Hospital, Kerman, Iran, from 2016 to 2017, and were diagnosed with lung cancer were enrolled into the study if they had a pathological sample of their cancerous lung. Their demographics were recorded, and the sample was sectioned and stained to measure HER2/neu gene expression according to DAKO instructions using heat-induced antigen retrieval (HIER) enzyme marker.
The samples of 100 patients with lung cancer were evaluated (84% men and 16% women) with a mean age of 61.34 years (standard deviation of 12.51 years). HER2/neu expression was significantly associated with the type of cancer and was highest in adenocarcinoma and zero in small cell carcinoma (P  0.05).
These results emphasized the overexpression of HER2/neu in different types of lung cancer, which can be used further for therapeutic purposes. The results showed that HER2/neu was overexpressed not only in adenocarcinoma but also in other types, like squamous cell carcinoma. Therefore, all subtypes of non-small cell lung carcinoma should be considered for anti-HER2 therapies, and further research is required for small cell lung carcinoma.

© 2023 The Authors. The Clinical Respiratory Journal published by John Wiley & Sons Ltd.