Next, kinase assay to deter mine if T oligo and radiation induce apoptosis in tumor cells injected into mice, sections of tumors from all groups were stained for apoptosis using the TUNEL assay. In tumors arising from cells pretreated once with T oligo alone we observed far more apoptosis even after 30 days compared with control oligo or medium alone. Few or no TUNEL Inhibitors,Modulators,Libraries positive cells were observed in tumors arising from control oligo or medium treated cells, and 3 Gy irradiation did not increase the apoptosis to a statistically significant degree. In tumors arising from cells trea ted with combined T oligo and radiation, the numbers of apoptotic cells increased significantly even after 30 days. At this time, an approximately three to six fold increase in apoptosis was observed in tumor cells treated with T oligo vs control oligo or medium alone prior to subcutaneous injection.

The one small tumor found in one mouse inocu lated with tumor cells treated with T oligo followed by 3 Gy IR contained many apoptotic cells. Inhibitors,Modulators,Libraries These experiments provide further evidence that pretreatment with T oligo can enhance the apoptotic killing of tumor cells by radiation, even by radiation doses that alone have only a modest effect. Effect of combined T oligo and radiotherapy on spontaneous mammary carcinomas in vivo When evaluating the efficacy of a therapy for breast can cer, it is desirable to use a tumor model Inhibitors,Modulators,Libraries that resembles breast cancer in humans as closely as possible. We and others have demonstrated that PyMT induced mammary tumors share many features in common with human breast cancer.

Therefore, MMT mice were used to evaluate the combined effect of T oligo and radiotherapy Inhibitors,Modulators,Libraries in the in vivo setting. Our pre vious studies showed that mammary tumors in Inhibitors,Modulators,Libraries MMT mice at Days 70 to 80 are in the early invasive stage. MMT mice aged 70 to 72 days DAPT secretase chemical structure received intraduc tal injections of T oligo at a dose of 210 ug in 50 uL PBS every other day in a right chest mammary gland. A left chest mammary gland was injected with the same dose of control oligo as a same animal control. After seven to eight injections, the mice were irradiated with a single dose of 3 Gy focused on the chest area. The control groups consisted of three littermates each that received no treatment, treated with T oligo and control oligo without radiation or treated with 3 Gy IR alone. Ten days after irradiation, the mice were sacrificed and the treated and control mammary glands harvested, processed for whole mount, and digitized. The tumor in the digital image was traced and analyzed by SPOT advanced soft ware. As shown in Figure 5a, b, mammary tumors in the mice without treatment or treated with 3 Gy alone reached the size of 58 6. 11 mm2 and 48 14. 18 mm2, respectively, statistically comparable.