Her-2/neu mRNA Expression by quantitative reverse transcriptase realtime PCR (qRT-PCR) on samples of bronchial wash is a biomarker for early diagnosis of non-Small Cell Lung Cancer

Even though lung cancer is the leading cause of cancer related death worldwide, there is no effective method for early detection and screening of the high risk groups. The diagnosis in more than 75% of cases is usually achieved after the appearance of symptoms which are late in the course of the disease. The currently used methods of the annual chest X-rays or sputum cytology are not sensitive screening tests. The new advances in the molecular genetics studies have opened new ways for implementation of biomarkers in the diagnosis, therapeutics and prognosis. Human Epidermal Growth Factor Receptor-2 gene (Her-2/neu gene) amplification and/or overexpression is seen in non-small cell lung cancer (NSCLC) and cancer of other organs. In this study, twenty-four samples of bronchial wash positive for NSCLC by cytopathology and thirty samples negative (control) were studied for expression of messenger RNA (mRNA) of Her-2/neu gene by quantitative reverse transcriptase realtime polymerase chain reaction (qRT-realtime PCR). Her-2/neu mRNA was expressed in all samples of bronchial wash (positive and control), and relative quantification of mRNA of Her-2/neu gene showed a significant increase of expression in bronchial wash samples positive for NSCLC compared to control (negative) samples after normalization with GAPDH as a housekeeping gene. In conclusion, Her-2/neu gene could be used as a biomarker for the early detection of NSCLC in bronchial wash in addition to its therapeutic significance.