ABSTRACT
Aim To investigate the effect of curcumin on radiosensitivity of radioresistant nasopharyngeal carcinoma cell line CNE-2R and its mechanism.Methods The concentration of curcumin was screened by MTT assay.Dose-survival curves were obtained according to the colony forming test for L-Q matching and multitarget-single hitting matching,while SF2 and the correlation parameters of radiation biology were calculated.The changes of cell cycle in CNE-2R cells caused by curcumin were also tested by flow cytometry(FCM).The differential expression of genes related to cell cycle and DNA damage repair were detected by RT-qPCR.Results CNE-2R cells could not be inhibited by 10 μmol·L-1 curcumin.Dealt with 10 μmol·L-1 curcumin for 24 h,the value of α/β increased to 1 596 from 6.56;the value of SF2 decreased to 0.361 Gy from 1.93 Gy;the value of N decreased to 1.06 from 1.60;the value of D0 decreased to 2.12 from 3.27;the value of Dq decreased to 0.12 from 1.53.FCM showed that the cells in G2 phase had a significant increase and the cells in S phase had a significant decrease after dealt with 10 μmol·L-1 curcumin for 24 h.The expression of CDK4 was significantly up-regulated and GADD45g,BRCA1 were significantly down-regulated.Conclusion Curcumin radiosensitizes nasopharyngeal carcinoma cell line CNE-2R by changing cell cycle and affecting DNA damage repair through regulating the expression of CDK4,GADD45 g and BRCA1.
ABSTRACT
Objective To establish radiation?resistant lung carcinoma cell lines, and to investigate the changes in morphology, apoptosis, invasive migration, and epithelial?mesenchymal transition ( EMT) in cells. Methods The radiation?resistant lung carcinoma cell lines were obtained by exposure of lung carcinoma cell lines, A549 and H1299, to radiation with a low dose in fractions, a sublethal dose, or a gradually increasing dose. The morphological changes in cells, radiosensitivity, survival rates after exposure, apoptosis rates, changes in invasive migration, and expression of EMT marker proteins were evaluated using microscopy, colony formation assay, CCK?8 assay, flow cytometry, transwell migration assay, and Western blot, respectively. Results Radiation with a gradually increasing dose successfully induced the radiation?resistant cell lines, A549R and H1299R. The morphological study showed that the morphology of radiation?resistant cells was converted to the morphology of mesenchymal cells. Compared with A549 and H1299 cells, the values of D0 , Dq , and SF2 were significantly increased in A549R ( P=0.017,P=0.001,P=0.000) and H1299R (P=0.033,P=0.000,P=0.008) cells, respectively;the values of α and α/β were significantly reduced in A549R (P=0.018;P=0.007) and H1299R (P=0.001;P=0.009) cells, respectively. The survival rates in A549R and H1299R cells after exposure to radiation with various doses were significantly higher than those in the control groups (all P<0.05). After exposure, the apoptosis rates were significantly reduced in A549R and H1299R cells ( P=0.02,P=0.01);the invasion and migration rates were significantly increased in A549R (P=0.000;P=0.001) and H1299R (P=0.001,P=0.002) cells;the expression of E?cadherin was significantly down?regulated in A549R and H1299R cells (P=0.00,P=0.01), while the expression of vimentin was significantly elevated in A549R and H1299R cells ( P= 0. 02, P= 0. 01 ) . Conclusions The radiation?resistant lung carcinoma cell lines are successfully established. Both cell lines show enhanced invasion and migration, which may be associated with EMT.
ABSTRACT
Objective:To observe the biological behaviors of colorectal cancer LS174 cells before and after pcDNA3.0-hugl-1 transfection,so as to investigate the association of hugl-1 with colorectal cancer.Methods:The eukaryotic expression vector pcDNA3.0-hugl-1 was constructed and transfected into LS174 cells.RT-PCR and Western blotting methods were used to analyze the expression of hugl-1 mRNA and protein in LS174 cells before and after transfection.Soft agar colony formation assay,wound-healing experiment,adhesion assay and Matrigel invasion assays were used to study the effects of hugl-1 expression on the proliferation,adhesion,movement and invasion in LS174 cells.Results:The recombinant plasmid pcDNA3.0-hugl-1 was successfully constructed.RT-PCR and Western blotting showed that the hugl-1 expression was higher in cells transfected with pcDNA3.0-hugl-1 than in those un-transfected or empty vector-transfected cells (P