Isolation Of Anthraquinones From The Roots Of Polygonum Multiflorum Thumb. And Radiosensitization Of GXHSWAQ-1 In Human Nasopharyngeal Carcinoma Cell Lines CNE-1

Nasopharyngeal carcinoma(NPC)is one of the common malignant tumors in Guangxi province,China.The incidence of NPC is as high as 30-50 per 100000 individuals.Owing to its special anatomic site and characteristic of radiosensitivity,the primary treating method lies in radiotherapy.But the radiotherapeutic treatment is not desirable.The data indicat that,about 10%to 18%NPC patients who had residual focus,20%to 30%NPC sufferers who had local recurrence,20%to 36%NPC sufferers who had distanct metastasis,one of the major causes of treatment failure was radioresisitant.Hence,to enhance the sensitivity of NPC cells to radiation is one way to improve the therapeutic effects.Anthraquinone and Ubiquinone compounds from Chinese herbs medicine are radiosensitizing agents,but the mechanism is not clear.Polygonum multiflorum thumb.,the dried roots of Polygonaceae botanic,is one of the common chinese traditional medicines in Gunagxi province.Its chemical constituents contain anthraquinones,diphenyl ethylenes and phospholipins.If we separated natural compounds from Polygonum multiflorum thumb,by modern chromatographic separation techniques,we would obtain some bioactive compounds and drug candidates which are cheaper,lower cytotoxicity and more effective therapeutic power.It is important and profound meaning for utilizing the natural resources of Guangxi province,accelerating development of the Modernization of Traditional Chinese Medicine,and improving the effectiveness of radiotherapy.7 compounds were isolated and purified from ethyl acetate extraction of Polygonum multiflorum thumb,by extraction with different organic solvents, various column chromatography,and recrystallisation methods.Spectroscopic data including IR,¹HNMR,and ¹³CNMR of those compounds were established for their chemical structural elucidateon.As a result,7 compounds were identified as:physcion(â… ),emodin(â…¡),questin(â…¢),β-sitosterol(â…£),gallic acid(â…¤),daucosterol(â…¥),GXHSWAQ-1(â…¦).To investigate the radiosensitization of GXHSWAQ-1(an Anthraquinone compound extracted from Polygonum multiflorum thumb.)in human nasopharyngeal carcinoma cell lines CNE-1 which is radioresistance tumor cells for 2 Gy and the expression of Ku70, Ku80,HIF-1 and ATM after GXHSWAQ-1 treated.The inhibition effects of GXHSWAQ-1 and sensitive enhancement ratio(SER)on thehuman CNE-1 cell lines were evaluated by MTT colorimetric assay.Ku70,Ku80,HIF-1 and ATM genes expression were detected by RT-PCR.The result showed that when the concentration of GXHSWAQ-1 was lower than 62.5μg/ml,there is no cytotoxicity for CNE-1 cell lines(Inhibitory ratio is lower than 10%).But at the concentration of 7.8μg/ml GXHSWAQ-1 could inhibited cells growth post-irradiation.The sensitive enhancement ratio(SER)of GXHSWAQ-1 was higher than that of Anka(Irisquinone capsules).The radio sensitivity related gene Ku70,Ku80,HIF-1 and ATM in CNE-1 cells were down-regulationafter treated with different concentration of GXHSWAQ-1.The result show that GXHSWAQ-1 is radiosensitizing effect in vitro on Nasopharyngeal Carcinoma cells.Radiosensitization by GXHSWAQ-1 is possibly associated with the expression ofku80,ku70,HIF-1 and ATM.