Screening And Identiifcation Of Tumor Marker In Lung Adenocarcinoma

1Background and ObjectiveLung cancer is the most common malignant tumor of breathing system, and the majority of it isusually bronchial epithelium evil deformation. It could be called bronchial lung cancer. The pathologicaltype of lung cancer include small cell lung cancer and non-small cell lung cancer, and the non-small celllung cancer accounts for more than80%, which can be divided into several types of adenocarcinoma,squamous cell carcinoma, large cell carcinoma, squamous adenocarcinoma and so on. In recent years, theincidence rate of lung adenocarcinoma is in the rapidly growing, and the age of onset is getting younger,more common in women. Basically the same as with other malignancies, adenocarcinoma cell can invasivegrow to the Bronchial lumen, lung and other organs, or transfer spread through lymph and blood. As aresult, most of patients are usually diagnosed at an advanced stage, losing the chance of operation andhaving low survival rate. Usually in lung adenocarcinoma of surgery, chemotherapy and radiotherapy arethe tradition method of comprehensive treatment, but can’t effectively improve patients five years ofsurvival. Clinical studies show that was diagnosed early in patients with lung adenocarcinoma, with thesurgical treatment of the combined radiation and chemotherapy, its5years survival rate can be as high as90%. And to have happened the transfer of lung adenocarcinoma, not for surgical intervention, the survivalrate is reduced greatly.At present the main clinical diagnosis method are imaging, laboratory biochemical examination,pathology and other means to but still have a large lung adenocarcinoma can’t be early cleared. So thestudy the pathogenesis of lung adenocarcinoma, early diagnosis and treatment have become the urgent task of literatures. So looking for lung adenocarcinoma specific tumor markers to improve the early diagnosisrate are problems to be settled instantly now. Making use of two-dimensional gel electrophoresistechnology and mass spectrometry, this study will establish the two-dimensional electrophoresis patterns ofthe protein in human lung adenocarcinoma and its paired cancer tissues, and analysis the proteinexpression difference between two ways, and in turn to find the related protein of diagnostic value.2SolutionFirst，take18tissue samples of fresh lung adenocarcinoma organization after surgical resectionand adjacent to tissues above5cm away from the tumor. Note that remove discernible stromal elements asmuch as possible to get purer tumor cells and adjacent noncancerous lung tissue cells. In the lowtemperature condition, the samples should be rinsed repeatedly by sterile saline water to remove bloodcomponents, and then preserved at-80C refrigerator. Organization total protein can be get after crackingorganization, homogenizing, and centrifugation at low temperature.Then making use of two-dimensional gel electrophoresis technology, conduct proteomicscomparative study between human lung adenocarcinoma and its paired cancer tissues, analysing atlas withthe help of ImageMaster2D Platinum5.0Software and finding the significant Protein spots. Then Diggingpart of significant difference of protein spots after enzymatic hydrolysis, use Matrix assisted laserdesorption ionization time of flight mass spectrometer detect the peptide segment, according to the testresults of the query protein database, and ultimately determine the protein type.3Results(1)Obtain a high-resolution and high-repetition Two-dimensional gel electrophoresis. Theaverage protein points of each silver stain map are1232±56and1158±71;(2)Analysing atlas with the help of Image Master2D Platinum5.0Software, there are63protein spots of more than three times the differences. Among these protein spots,12only express in lungadenocarcinoma organization,5only express in paired adjacent organizations;(3) We choose only in lung adenocarcinoma organization of the12protein expression high pointthrough the MALDI-TOF-TOF-MS mass spectrum identification,11protein points to be identifiedsuccessfully.To remove redundancy, identified five kinds of proteins and the peptide mass fingerprinting oflung adenocarcinoma proteins can be obtained. The five kinds of proteins are23KD-albumin, S100-A11,Ras associated protein Rab-14, Stathmin,Gelsolin.4ConclusionThe experimental results combined with reports in the literature, exclude experiment systemerrors and individual differences，23KD-albumin is a failure to complete removal of tissue specimens ofblood components. Gelsolin, S10011, Ras-related protein Rab-14, Stathmin, these four proteins aretumor-associated. They may be involved in the lung adenocarcinoma invasion and metastasis of cancercells, signal regulating, differentiation, proliferation, secretion and cycle activities. These four differentproteins can be used lung adenocarcinoma of the candidate tumor markers, also can be used for screeninglung adenocarcinoma early diagnosis, treatment and prognosis of assessment of tumor marker laid afoundation.