| Nephroblastoma is one of the most common abdominal malignant tumor in children. It consists of 8% in all pediatric solid tumors. Max wilms descripted its characteristics in 1899, so it was named after his name. Nephroblastoma generates from metanephric blastemic rest cells, probably resulting from delayed and residual differntation of metanephric blastema. Its main prognosis factors are the histological structure, age, the totally excision of original tumor, metastasis and two sides tumor, but the most important prognosis factor is local infiltration and instant metastasis of the tumor.Tumor metastasis is a process which include a malignant tumor dispartting from the original tumor position, spreading from one part of the body to another through kinds of transferring ways and developing and growing in secondary tissue or organ, at last forming the same character of secondary tumor as the original. Metastasis is the basic biological character of malignant tumor and is the deadly factor in most of tumor patients in clinic.In recent years, there are many detailed statements about the proccess of tumormetastasis and continuously found many genes related with it. PTEN gene is one of the cases. To our known, the level of phosphorylation within cells is tightly regulated by the concerted action of protein kinases and protein phosphatases.Disregulation in the activity of either of these players can lead to cellar transformation. Many protein tyrosine kinases are proto-oncogenes and it has been postulated that some protein phosphatases may act as tumor suppressors. PTEN /MMAC1/TEP1 was detected by three laboratories at the same time in 1997.Now it is identified as a new candidate tumor suppressor and plays in signal transduction and tumorigenesis. PTEN is a dual specificity protein phosphatase (towards phospho-Ser/Thr and phospho-Tyr) and, unexpectedly, also has a phosphoinositide 3-phosphatase activity. Its normal expression can suppress the growth, infiltration and metastasis. Its losing of activity has relationship with cell signal transferring, the beginning of tumor,infiltration and metastasis, malignant transforming, uncontroled growing and clinical prognosis. It is reported that, the deletion and mutation of PTEN can be obsevered in many kinds of tumors. As a result, it is believed that PTEN gene is anthor tumor suppressor gene after p53 finding which has close relationship with tumor development and metastasis and can be detected changing in intensively in many kinds of tumors.Rel/NF- K B transcription factors or named nuclear factor K gene binding, NF- K B, is a kind of protein which is found extensively in cell and has regulatting function in multi-direction. It plays an important role in the development and apoptosis proccess of tumor cells.The expression of the human Ki-67 protein is strictly associated with cell proliferation. During interphase, the antigen can be exclusively detected within the nucleus, whereas in mitosis most of the protein is relocated to the surface of the chromosomes.The fact that the Ki-67 protein is present during all active phases of the cell cycle (Gl, S, G2, and mitosis), but is absent from resting cells (GO), makes it an excellent marker for determining the so-called groeth fraction of a given cell population.Untill now, the merchanism of nephroblastoma's metastasis has not been elucidated. So investigating the expression of PTEN gene protein, NF- K Bp65 andKi-67 protein and the relationship between them may shed a light on discovering the merchanism of nephroblastoma's metastasis, and providing the basis of research to inhibit tumor metastasis and gene therapy.Materials and methods:We have collected 42 children nephroblastoma specimens (tumor group) and 12 normal renal tissue near the tumor (control group) from surgical resections, and all the sections were formalin-fixed and paraffin-enbedded. The patients, from 4 months to 13 years, average 3.83, 27 males and 15 famales, were not performed any radiotherapy and chemotherapy. Their HE staining...
|
PDF Full Text Request