| The occurrence, progression and metastasis of tumor, related with many factors, is a complex multiple - phases process. Alterations of genes are very common during the tumor development, A new discovered anti - oncbgene, Pten, has been proved to relate with the formation of tumor, especially with progression of tumor. The gene was cloned by three research teams respectively, and was named different-ly.As the first discovered anti - oncogene possessing the activity of phosphatase, Pten has attracting more people to study it. Li and Steck discovered different somatic mutations through detection of Pten in brain tumor, carcinoma of prostate, mammary cancer and some other primary tumors. Germline mutations were observed at different sites on Pten in a few inherited diseases, such as Cowden disease and Adolescent Polyp of Colon. The reported deletion rate on some primary tumors: 27% ~50% in lung cancer,48% in mammary cancer, 48%in melanoma,37% in pancreatic carcinoma and 35% in thyroid carcinoma. Sano et discovered that the expression of Pten protein had correlation with pathological grading and prognosis. He represented that the worse prognosis, the lower differentiation, and the lower Pten protein expression. This research is to explore the relations between the Pten and malignancy, lymph node metastasis.Material and MethodMaterial: Total of 87 cases, all from department of chest surgery, China Medical University, between the period of 1995 ~2001, including 42 lung adenocarcinoma and 45 lung squamous carcinoma, were diagnosed by the department of pathology. 21 high differentiation, 10 medium differentiation and 56 low differentiation was included in this group and the group was consisted of 23 N00, 17N1, 47 N2. The resected specimens of 20 lung benign tumor were taken as control team. The specimen, fixed in 4% Formaldehyde, was buried in paraffin. The group was consisted of 63 males and 24 females, whose age ranged 36 -83, average 58.4. No distant metastasis was found in the group and no patient received chemotherapy or radiptherapy.The main instrument and reagent; resection machine ( BRIGHT 5040 made in English ) , GRANSE microwave oven, OLYMPUS BH2 microscope etc. Primary antibody, used in this experiment, was from NeoMarkers. USA Company. The immunohistochemistry reagent box was bought from Zhongshang biological reagent company in Beijing. The concentration of primary reagent is 1:50. DAB was provided by the laboratory of chest surgery department.Methods: The specimen was resected into 5um section and thebenign tumors ( pulmonary tuberculosis and bronchiectasis) were taken as positive control group. PBS, instead of primary antibody, acted as negative control group. The experiment procedure: the removal of paraffin of section, inactivation, antigen repair, stain, restain, dehydration, cover.Standard of Observed ResultsThe parts that stained positive were observed to lie in the cytoplasm of the cell. The positive stained part show brown. Ten randomly chosen visual fields were observed on each section under microscope. The proportion of positive stained cells was calculated among 100 tumor cells. ( - ) indicating negative, no cell was stained positive; ( + ) indicating weak positive, less than 20% cells were stained positive; ( + + ) indicating positive, more than 20% cells were stained positive. The part of weak positive was classified into negative group. Chi - squared test was applied to analyze the results of experiment . P <0. 05 represent marked statistical significance, and p <0. 01 represent extraordinary statistical significance.Result1. The positive rates for Pten were 50. 6% in 87 lung cancer, 90% in 20 benign tumor, and p <0.01 between two groups.2. The positive rates for Pten were 61.9% (26/42) in adenocar-cinoma, 40. 0% (18/45) in squamous carcinoma. P <0.05 differentiation between two groups.3. The positive rates for Pten were 90.5% (19/20) in high dif-ferentiation, 60. 0% (6/10) in medium differentiation, and 33. 9% (19/56) in low differ...
|
PDF Full Text Request