The Expression Of Tiam1 In Tumor Tissues Of Patients With NSCLC By RT-PCR And Its Clinical Significance

Lung cancer is one of the most common malignant tumors in the world , according to the statistics, with nearly 1.5 million new cases worldwide each year. Lung cancer is divided into small cell lung cancer (SCLC) and non-small cell lung cancer(NSCLC). The percentage of SCLC is only 15-20%, the most part is NSCLC. In the recent years, although the research of mechanism, development and therapy methods of lung cancer has gain great progress, the survival rate of lung cancer is still very low(only about 15%), which is related to the recurrence and micrometastasis. Therefore, detecting the micrometastasis with various advanced molecular biological diagnostic techniques has become one of the hot spots in the present research.At present, many methods are used to detect micrometast-asis, including pathological detection,IHC,RT-PCR, flowing cytometry and so on. Routine pathological detection is the gold standard of diagnosing lymph node micrometastasis ,but it is limited by the location of examples and the objective factors always infulunce the consequence. The sensitivity of IHC is better than routine pathological detection , at the mean time ,the examiner can do the morphological viewing with microscope directly. But it deserves serial section , the work load is large and the cost of applying antibody is too high. FCM is an accurate and sensitive process to detect micrometastasis , but the cost is too much and can not be generally applied in clinical practice.This experiment applies RT-PCR technique to prove the existence of micrometastasis in NSCLC by detecting the expression of Tiam1. Its sensitivity is 10-6to 10-7 , much better than other methods. RT-PCR is a objective index and it is a quantative method, the positive result can prove the existence of tumor cells. This method is accredittde by most people.Habets and his teamers have identified a gene, designated Tiam-1, which affects invasion and metastasis in many kinds of cancers such as colorectal cancer and breast cancer. Tiam1 transcripts were found in virtually all analysed tumor cell lines of human origin including B- and T-lymphomas, neurobla-stomas, melanomas and carcinomas. Tests suggest it has general function in cellular signaling processes.I choose Tiam1 as the molecular marker of NSCLC lymphnode metastasis, select 83 NSCLC tumor tissues and 11 lung nomal tissues ,abstact their totol RNA and then apply RT-PCR and agarose gel electrophoresis to detect its expression in cancer tissues and the tissues beside cancer, at the mean time I abstract some normal tissue as the contrast. The purpose of this experiment is to investigate the different expression rate of tissues from different source, the relationship between the expression of Tiam1 and lymph node metastasis, and the connection with the age, gender, pathotype and the degree of cell differentiation. The analysis of data is finished with the statistics software SPSS 13.0 .The results manifest:1. The expression of the Tiam 1 incancer tissue has clearly increased, which demonstrates they are functioning in the happening and the development of NSCLC.2. The expression of the Tiam1 in the lung cancer cases which have the metastasis is obviously higher than the one that does not have. It proves that the expression of Tiam1 is closely related to the lymph node metastasis of NSCLC. The higher expression, the stronger the invasion and lymph node metastasis.3. The expression of the Tiam1 is greatly related to the TNM staging of NSCLC. The higher expression, the higher staging.4. The patients'age, gender and pathological type do not have great affect on the expression of Tiam 1 . 5.RT-PCR is a reliable method to detect lymph node metastasis of NSCLC.