Expression Of E-cadherin, CD₄₄V₆ And Nm23 In Nasopharyngeal Carcinoma: The Clinical Significance And Interventional Experiment In Vitro

Nasopharyngeal carcinoma( NPC )is apt to develop metastasis with cervical metastasis rate of 80%. More than 20% of advanced NPC(N2, N3) developed distant metastasis. Distant metastasis and local regional recurrence account for the major reasons of treatment failure. It is of great importance to estimate the risk of metastasis of NPC. Traditional TNM stages system can not sufficiently reflect the biological character of NPC. Therefore, to predict the risk of metastasis of NPC, seeking for some molecular markers is needed.Tremendous research showed lately that the development and metastasis of human cancer are closely associated with inactivation of cellular adhesive molecular and metastasis inhibitive gene. The abnormal expression of transcript variant of CD44V6exon is intimately relevant to malignant phenotypes and metastasis of cancer, which thereafter influence its prognosis. E-cadherin is the main member in Ca-mucoprotein family, which is associated with differentiation and invasion of carcinoma cell. Lost or reduced expression of nm23 gene is associated with tumor metastasis. In this study, specimens from 59 NPC were examed by immunohistochemical staining for E-cadherin, CD44V6 and nm23. The immunohistochemical data were correlated with WHO classification, TNM stages, cervical metastasis, distant metastasis and suvival.Arsenic trioxide has attracted great interest in the field of oncology since it was successfully used to treat acute promyelocytic leukemia. It also inhibited proliferation and induced apoptosis and differentiation of NPC cell in vivo and in vitro. But whether it has any effect on the character of metastasis of NPC cell remains unknown. Studies demonstrated that arsenic trioxide of low concentration induced differentiation of malignant cell, whereas the one of high concentration induced apoptosis. Since arsenic trioxide induced immature malignant cells into differentiated and mature ones, it undoubtedly altered somebiological character of the malignant cells. Presumedly, it could alter the invasive and metastatic ability of the tumor cells. We try to find out some clues of its possible inhibiting effect on the metastasis of the cancer cells.MethodsExpression of tumor metastasis associated proteins E-cadherim nm23 andCD44V6 in NPC1 Objective: The selected 59 cases of NPC underwent radiotherapy at the Department of Radiotherapy in Shantou University Cancer Hospital during 1997 had been followed up for more than 5 years. Specimens of the patients were studied by immunohistochemical staining for E-cadherin, CD44V6 and nm23. The immunohistochemical data was correlated with WHO classification, TNM stages, cervical lymph node metastasis and suvival.2 HE staining: cell morphology was observed under microscopy.3 Immunohistochemistry: the expression of E-cadheriru nm23 and CD44V6 in NPC cells was detected with Elivision method.4 Statistic analysis: All the data was analysized by SPSS10. 0 Statisticssoftware, with X2 analysis comparing rate (including 5-year survival rate)and Kaplan-Meier method (Log-Rank test)analysing survival. Arsenic trioxide' s effect on the expression of E-cadherin nm23 and CD^Vein CNE-2 cells1 Objective: CNE-2 cells.2 Cell morphology: Invert microscope and HE staining.3 Immunohistochemistry: With vacuity culture medium as control group, CNE-2 cells were treated with different doses of arsenic trioxide (0.01g/ml 0.03g/mK 0. lug/ml 0.3g/ml 0.5g/mK 1g/ml and 2 g/ml respectively). After 24h 48h and 72h incubation, the expression of E-cadherin nm23 and CD44V6 on CNE-2 cells was detected with Elivisionmethod. The process was repeated for 3 times.4 Statistic method: All the data was analysized by SPSS10. 0 Statisticssoftware.ResultExpression of metastasis associated proteins E-cadherin nm23 and CDVin NPCPositive expression rates of E-cadherin, nm23 and CD44V6were 88.1%, 79. 6% and 57. 6% respectively. Reduced expression of E-cadherin and nm23 were found in 47. 5% and 64. 4% of NPC specimens. In keratinizing squamous cell carcino...