Enhancer Of Zeste Homolog 2(EZH2) Influences The Chemoradiotherapy Sensitivity Of NK/T Cell Lymphoma

Malignant lymphoma is also called lymphoma,which is occurred in lymph nodes,spleen,thymus and other lymphoid organs and(or)Extranodal lymphoid tissue.Lymphoma is divided into two categories,namely non-hodgkin's lymphoma(NHL)and Hodgkin lymphoma(HL)[1].90% were non-hodgkin's lymphoma.Non-hodgkin's lymphoma was caused by abnormal proliferation of monoclonal transformed T and B lymphocytes differentiated from different mature stage.About 70%-85% of the NHL is derived from the B lymphocytes.Mature T cell tumor is originated in the mature T cells malignant tumor.NK cells have similarities with T cells in the immune phenotype and function.So in REAL classification and the WHO classification,it discuss NK cell lymphoma and T cell lymphoma together.Mature NK/T cell lymphoma also called peripheral t-cell lymphoma(PTCL),accounting for 7% of all NHL,with difficult pathological diagnosis,low treatment efficiency,and short survival time[2].The NK/T cell lymphoma treatment mainly includes mainly anthracycline-based chemotherapy,radiation therapy andchemoradiotherapy combined with comprehensive treatment.the 5-year survival rate is 45%,64% and 86% respectively,with overall CR rate was only 33% and the recurrence rate of 57% in 6 month.The median survival time is about six months[3].Studies have shown that: the chemotherapy drug resistance and radioresistance are important factors affecting the tumor recurrence.Therefore,clarify NK/T lymphoma molecular mechanism of chemotherapy drugs and radioresistance,is particularly important.EZH2 is PRC2 core catalytic subunit possessed trimethylated histone transferase activity,which induced inhibition of tumor suppressor gene transcription,resulting in the occurrence of tumor[4,5].EZH2 can affect tumor cell proliferation,apoptosis,cell cycle and invasive,and plays an important role for epigenetic regulation.It has been proved to regulate the hematopoietic system,proliferation and differentiation of neural stem cells and skeletal muscle cells.EZH2 is maintain the malignant tumor cell proliferation potential and the ability to prevent tumor cell aging.EZH2 are highly expressed in many malignant tumors,including breast cancer,lung cancer,renal cell carcinoma and malignant melanoma,prostate cancer and endometrial cancer and head andneck squamous cell carcinoma,promote tumor growth and metastasis,and high expression of EZH2 prognosis of malignant tumors of the lower express or express EZH2 type difference[6-8].These results suggest that EZH2 will play an important role in future clinical diagnosis,prognosis prediction and tumor targeting therapy.This experiment through the establishment of EZH2 high expression of NK/T lymphoma cell lines SNK-6,application lentivirus carrying interference EZH2 sh RNA knockout NK-T lymphoma in endogenous EZH2,cell apoptosis in experimental group and control group,the number of apoptosis protein fault zone and the radiation and chemotherapy sensitivity of different,the results showed that the inhibition of the expression of EZH2 can significantly enhance the cell apoptosis rate,states that EZH2 is associated with NK/T lymphoma cell proliferation of an important oncogene.Therefore,it has the potential to be a new therapeutic targets for the treatment of NK/T lymphoma in the future.