Determination of her-2/neu amplification through fluorescense in-situ hybridization in non small cell lung cancer

SUMMARYDETERMINATION OF HER-2/neu AMPLIFICATION THROUGHFLUORESCENSE in-situ HYBRIDIZATION IN NON SMALL CELL LUNGCANCER *ebnem YıldırımcanIn terms of human health, one of the most important problems is cancer nowadays.Among the types of cancer, lung cancer; by increasing rapidly its incidence, has become themost widespread type of cancer among men and women in western countries. Lung cancer,according to morphology of cells is mainly divided in two types named as non small cell lungcancer (NSCLC) and small cell lung cancer (SCLC). 80 percent of all lung cancers are nonsmall cell lung cancer.Lung cancer has fairly bad prognosis and it has been proved that more than 90 percentof the cases which are diagnosed have ended with dead. In this state, prognostic signs andnew approaches in treatment gain importance. It has been claimed that variety of molecularalterations play significant role in tumour prognosis.HER-2/neu oncogene, one of the genes which is exposed to change and is located at17q12, encodes a 185 kDa transmembrane receptor tyrosine kinase which is named asp185HER2 . The amplification of HER-2/neu gene and as a result of this the overexpression ofreceptor causes increase of cell division and fastening of cell growth. HER-2/neuoverexpression has been reported in 10-15 percent of non small cell lung cancer patients andin 30 percent of adenocarcinoma.In this study, it has been aimed to evaluate HER-2/neu amplification by means ofFISH and searching the effect of HER-2/neu amplification on prognosis, by connecting theclinic data of cases with results, in tumour samples of non small cell lung cancer cases. Alsoin recent years, it has been got evidence about that Herceptin which binds p185HER2 andwhich is recombinant DNA derived monoclonal antibody may use associated withchemotherapy. Precondition of successful treatment thanks to Herceptin is that HER-2/neuamplification rightly determine.In our study, it was determined HER-2/neu gene amplifications with FISH in parafintissue samples of 23 NSCLC cases which were evaluated as negative (%46), +2 (%29) and +3(%25) t, with the help of immunohistochemistry. The analysis results with HER2/CEP17 ratio2.0 were accepted as FISH positive; on the other hand analysis results with HER2/CEP 17ratio <2.0 were accepted as FISH negative. As the result of maded evaluations, it was foundas FISH negative 100 percent of 24 cases and it was evaluated as balanced dysomy 22 andbalanced quadrisomy one of these cases. To our results, a significant connection betweenprognosis and FISH consequences cannot been determined. Besides, it has been determinedthat overexpression of HER-2/neu protein is not associated with real gene amplification.Key words : Non small cell lung cancer, HER-2/neu, Herceptin, FISH* This study was supported by Dokuz Eylül University, Scientific Research Department.Project No: 2005.KB.SAG.022