5% crystal violet and counted. The plating efficiency scientific research and the surviving fraction were cal culated by using the formula PE �� 100% and SF �� 100%. The standard radiation Inhibitors,Modulators,Libraries survival curve was constructed and the mean lethal dose, which represents the dose required to reduce the frac tion of surviving cells to 37% of its previous value, was calculated by fitting the data with the multitarget single hit model and linear quadratic model. Immunofluorescent gH2AX staining Tumor cells plated into eight well chambers were pre treated with T oligo or control Inhibitors,Modulators,Libraries oligo for 24 hours and then irradiated. After radiation, cells were fixed in 4% paraformaldehyde, and then treated with a 0. 2% NP40 PBS solution for 15 minutes at room temperature.

Cells were washed with PBS and incubated for two hours with anti gH2AX, followed by incubation with FITC conjugated anti mouse IgG for one hour. Slides were immersed in 0. 05 mg ml DAPI for five minutes and then mounted with cover slips using ProLong Antifade Kit. Slides were viewed Inhibitors,Modulators,Libraries with a Nikon Eclipse E400 fluorescence microscope and the images were captured by a digital camera and analyzed using SPOT advanced software. The number of gH2AX foci per cell was counted and determined in at least 70 cells for each group. Single cell gel electrophoresis assay To compare the degree of DNA fragmentation, mam mary tumor cells were pretreated with 40 uM T oligo or control oligo for 24 hours, and then subjected to irra diation. Three hours after radiation, cells were Inhibitors,Modulators,Libraries trypsi nized to single cell suspension and adjusted to the concentration of 1 �� 105 cells ml.

Cell suspensions and 1% Inhibitors,Modulators,Libraries low melting point agarose were gently mixed at 37 C and added onto each Comet Slide. The slides were gelled at 4 C in the dark for 30 minutes, and then immersed in prechilled lysis solution for 60 minutes. Then the slides were immersed in freshly prepared alkaline buffer for 60 min utes to allow the DNA to unwind prior to electrophor esis at 1 Volt cm for 30 minutes at 4 C. Air dried slides were stained for five minutes with 10 ul DAPI, and then rinsed in cold water and covered with a cover slip. The nuclei were analyzed by use of a fluores cence microscope. Hydroxyl radical induced DNA damage by H2O2 was used as a positive control. TriTek CometScore software was used to measure the percentage of DNA in tail. At least 45 cells on each slide were measured.

b galactosidase staining Mammary tumor cells were cultured in either medium alone or medium containing T oligo or control T oligo at a concentration of 40 uM for 24 hours, and selleck chemicals Imatinib then irra diated with 3 Gy. Twenty four hours after radiation, the cells were washed in PBS and fixed with formaldehyde gluteradlehyde solution for 10 minutes at room temperature and stained with an X gal mixture 6, 5 mM K3Fe 6, 150 mM NaCl, 2 mM MgCl2, 1 mg ml X Gal for 24 hours at 37 C.