Lung cancer is the most common cause of cancer-related death in the world. The main types are small-cell lungcarcinoma (SCLC) and non-small-cell lung carcinoma (NSCLC), the latter including squamous cell carcinoma(SCC), adenocarcinoma and large cell carcinoma. NSCLCs account for about 80% of all lung cancer cases.Microcephalin (MCPH1), also called BRIT1 (BRCT-repeat inhibitor of hTERT expression), plays an importantrole in the maintenance of genomic stability. Recently, several studies have provided evidence that the expressionof MCPH1 gene is decreased in several different types of human cancers. We evaluated the expression of proteinMCPH1 in 188 lung cancer and 20 normal lung tissues by immunohistochemistry. Positive MCPH1 stainingwas found in all normal lung samples and only some cancerous tissues. MCPH1-positive cells were significantlylower in lung carcinoma compared with normal tissues. Furthermore, we firstly found that MCPH1 expressionin lung adenocarcinoma is higher than its expression in squamous cell carcinoma. Change in MCPH1 proteinexpression may be associated with lung tumorigenesis and may be a useful biomarker for identification ofpathological types of lung cancer.
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