Effect Of Elemene On Radiosensitivity In Human U251 Glioma Cell Line

Background and Objective:Glioma is the most common intracranial tumor,accounnting for 40%-50%.Surgical treatment is the preferred method for gliomas;after surgery the radiotherapy,chemotherapy and other adjuvant therapy are often be selected,but the efficacy is still not ideal.Tumors are not sensitive to radiotherapy is an important reason. Finding Radiosensitizer is an important direction for the treatment of glioma.This experiment aims to investigate the effects of Elemene on the radiosensitivity of U251 glioma cell line in vitro and its mechanism.Methods:Cell growth inhibition was assessed by MTT (microculture tetrazolium assay) after incubated with Elemene at various concentrat-ions and times. U251 cells were divided into 4 groups:blank group,drug group (deal with Elemene),irradiation group (deal with irradiation) and combination group (deal with Elemene and irradiation). The effects of Elemene combining radiation to U251 cells were tested by clonogenic assay,"multi target single hit survivalmodel" [SF=1-(1-e-D/D0)N)]was used for dealing with data, then the cellsurviving curve, DO, Dq and SER were obtained. When U251 glioma cell line was treated with different concentrations of Elemene for 24hours,apoptosis ratio was analyzed by flowcytometry(F-CM).Results:Elemene could inhibite the growth of U251 glioma cell line,and IC50 of 24h was 137.02mg/L and the 48h's was 106.06mg/L. Elemene 20mg/L and 40mg/L both had radiosensitive effect on U251 cells exposed for 24h, and SER of which were 1.179 and 1.429; U251 cells exposed for 3h and 6h by Elemene 40mg/L both had radiosensitive effect too, and SER of which were 1.139 and 1.356. Apoptosis rates of trial group(20,40)mg/L were (11.98±0.25)%,(16.65±0.44)%, and control group was (8.33±0.43)%, there was significant difference among three groups (P< 0.05).Conclution:1. Elemene can inhibit the growth of U251 glioma cell line, and the effect was associatted with the concentration and reaction time.2.Elemene can promote radiosensitivity of U251 glioma cell line, treating with different concentrations or time the radiosensitivity may be different.3.Increasing apoptosis is one of the mechanism that Elemene enhances radiosensitivity of U251 glioma cell line...