Proceedings of the 50th Annual ASTRO Meeting S701

intraperitoneal (i.p.) Amifostine 30 minutes prior to RT; 5) RT combined with twice weekly i.v. injections of CeO2; and 6) RTcombined with Amifostine i.p 30 minutes prior to RT. The weight and mortality of each mouse was measured throughout theexperiment.

Results: Cell viability and cell death assays showed that CeO2 protected 99% of normal breast cells from radiation-induced celldeath (RICD), whereas breast cancer cells were not protected with CeO2. In the lung cell lines, the number of viable cells was sig-nificantly decreased in both normal and cancer lines after RT, as measured by ATP quantitation (signaling metabolic activity). WithCeO2 prior to RT, normal lung cells were protected from RICD whereas lung cancer cells exposed to RT pretreated with CeO2 werenot. In the presence of CeO2, normal cells were protected from RICD as measured by the activity of Caspase 3/7 (an apoptosis mea-sure), whereas lung cancer cells were not. In the mice safety experiments, nanoparticles were well tolerated and protected mice fromRICD. All control mice lived until termination date of 207 days. When treated with CeO2 alone, 80% of mice were alive on termi-nation date. After treatment with RT alone, Amifostine alone, and a combination of RT and CeO2, or RT and Amifostine, the mediansurvival time was 132, 119, 210, and 81 days, respectively (control versus RT, p \ 0.019; control versus CeO2p \ 0.66, controlversus Amifostine, p \ 0.0370; RT versus radiation and CeO2p \ 0.0041; RT versus RT and Amifostine, p \ 0.0432). Therewas no significant difference in the median survival of mice between control and CeO2 treatment. In contrast, Amifostine was toxic.

Conclusions: Our preliminary studies have identified that cerium oxide nanoparticles (free radical scavengers) protect normal butnot cancer cells from radiation, which leads to a novel approach to increase the efficacy and decrease side effects of radiation ther-apy for cancer patients.

Author Disclosure: J. Colon, None; L. Herrera, None; S. Patil, None; S. Seal, None; W. Jenkins, None; P. Kupelian, None; C.Baker, None.

3184 Effect of Cisplatin and Radiotherapy Induced Oral Mucositis by Recombinant Human Epidermal Growth

Factor in Mice

K. Kang1, H. Kim2, G. Chai1, S. Lee3, K. Jang2, B. Choi4, H. Jang4, B. Jeong1, J. Na5

1Radiation Oncology, Gyeongsang National University, School of Medicine, Jinju, Republic of Korea, 2Pharmacology,Gyeongsang National University, School of Medicine, Jinju, Republic of Korea, 3Radiation Oncology, University of UlsanCollege of Medicine, Seoul, Republic of Korea, 4Radiation Oncology, Catholic University of Korea, College of Medicine, Seoul,Republic of Korea, 5Diagnostic Radiology, Gyeongsang National University, School of Medicine, Jinju, Republic of Korea

Purpose/Objective(s): The epidermal growth factor (EGF) is involved in inflammatory and cancer. The salivary EGF levels havebeen shown to be markedly reduced in patients with oral inflammation of head and neck tumors. The EGF acts primarily to stim-ulate epithelial cell growth across the inflammation, but it can also act on fibroblasts and smooth muscle cells. To study the effect ofrecombinant human epidermal growth factor (rhEGF) on oral mucositis induced by cisplatin and radiotherapy in a mouse model.

Materials/Methods: Twenty four ICR mice (7-8 week, male) were divided into 3 subgroups including normal control group (8),no rhEGF group (cisplatin + irradiation) (8) and rhEGF group (cisplatin + irradiation + rhEGF) (8). A model of mucositis inducedby cisplatin and radiotherapy was established by injecting mice with cisplatin (10 mg/kg) on day 1 and irradiation (5 Gy/day) to thehead and neck on days 1 to 5. RhEGF was administration subcutaneously on days -1 to 0 (1 mg/kg/day) and on days 3 to 5 (1 mg/kg/day). Evaluation included body weight, intake of oral, and histopathology.

Results: For the comparison of the change of body weight between the rhEGF group and the no rhEGF group, a statistically sig-nificant difference was observed in the rhEGF group for the 5 days after day 3 of the experiment (p\0.05). The rhEGF group andno rhEGF group had reduced food intake until day 5 of the experiment, and then the mice demonstrated increased food intake afterday 13 of the experiment. When the histological examination was conducted on day 7 after cisplatin and radiotherapy, the rhEGFgroup showed a focal cellular reaction in the epidermal layer of the oral mucosa, while the no rhEGF group did show inflammationof the oral mucosa.

Conclusions: These findings suggest that rhEGF has a potential to reduce the oral mucositis burden in mice after cisplatin andradiotherapy. The optimum dose, number and timing of the administration of rhEGF require further investigation.

Author Disclosure: K. Kang, None; H. Kim, None; G. Chai, None; S. Lee, None; K. Jang, None; B. Choi, None; H. Jang, None; B.Jeong, None; J. Na, None.

3185 Pelvic Irradiation Induces a Systemic TNF-a Response and Sickness Syndrome in Mice: Implications for

Cancer Treatment Related Fatigue

L. J. Wood1, T. McDonald1, D. Roberts1, X. Han1, A. Hung1, C. R. Thomas2

1OHSU, Portland, OR, 2Oregon Health & Science University, Portland, OR

Purpose/Objective(s): Patients undergoing external beam radiation therapy (EBRT) for prostate cancer experience a progressiveincrease in fatigue which can affect physical functioning, and QOL. Treatment related fatigue can persist for months after treatmenthas ended. It has been suspected that this fatigue is the same as sickness syndrome, caused in large part by the systemic productionof the pro-inflammatory cytokine TNF-a. Yet, whether localized EBRT, can cause a rise in systemic TNF-a and sickness syndromeis not known and is the focus of this study.

Materials/Methods: To determine the effects of EBRT on sickness syndrome in mice, weight, food intake and wheel runningactivity were assessed in male C57BL/6 mice undergoing EBRT to the pelvis. Baseline average daily food intake, weight and ac-tivity level were measured over a two week period prior to EBRT. Twenty mice underwent EBRT under anesthesia to the pelvisusing a fractionated dose of 2.84 Gy, 5 days per week for 24 fractions for a total dose of 68.2 Gy, thereby mimicking the clinicaltherapeutic dose. Twenty mice (controls) were treated in an identical manner but were not irradiated. The day after the last radiationdose, 10 mice from each group were sacrificed and liver levels of TNF-a mRNA were measured by quantitative real time PCR(qRT-PCR). Plasma levels of TNF-a were measured using a bead-based immunofluorescence assay. The remaining mice weremonitored for a further 3 weeks, prior to sacrifice and tissue collection.

S702 I. J. Radiation Oncology d Biology d Physics Volume 72, Number 1, Supplement, 2008

Results: Irradiated mice showed a progressive decline in body weight and daily activity compared to controls. Food intake duringtreatment was no different between the two groups. At the end of treatment, plasma levels of TNF-a and liver TNF-a mRNA levelswere significantly elevated compared to control mice. Three weeks after the last treatment dose activity level and body weight hadstill not returned to pre-treatment levels. At this time point plasma levels of TNF-a were significantly increased in mice adminis-tered RT relative to controls.

Conclusions: Study findings demonstrate that localized EBRT can induce a systemic TNF-a response and sickness syndrome inmice that persists weeks after treatment has ended. Further experiments using TNF-deficient mice will allow us to determine therole of TNF-a in sickness syndrome induced by EBRT. This information may lead to targeted strategies aimed at blocking TNF-a in men undergoing localized EBRT with the aim of reducing treatment related fatigue thereby improving QOL.

Author Disclosure: L.J. Wood, None; T. McDonald, None; D. Roberts, None; X. Han, None; A. Hung, None; C.R. Thomas, None.

3186 Effect of American Ginseng on Total Antioxidant Capacity and Reactive Oxygen Species of Human137

Lymphocytes before and after Cs-Irradiation

T. Lee1, W. Wang1, O’Brien K.2, R. Johnke1, T. Wang1, R. Allison1

1Brody School of Medicine at ECU, Greenville, NC, 2School of Allied Health at ECU, Greenville, NC

The major mechanism of ionizing radiation (IR)-induced cell death and tissue damage is the generation of reactive oxygen species(ROS) that attack cellular DNA. For cancer patients receiving radiotherapy (RT), IR-induced normal tissue damage is a dose-lim-iting factor. Ginseng is one of the most frequently purchased herbs in the United States. The multifold bioactive properties of ginsenghave been linked to its antioxidative ability. Since effective antioxidants are free radical scavengers that interfere with radical chainreactions, it is possible to protect cellular DNA from oxidative stress by supplying antioxidants. To test this hypothesis, and toexplore the radioprotective potential of North American Ginseng Extract (NAGE), we evaluated the effect of NAGE on total anti-oxidant capacity (TAC) and ROS of peripheral blood lymphocytes (PBL) obtained from 10 volunteers before and after 137Cs irra-diation (0.6 Gy/min, 1 -2 Gy) ex vivo. At three different time points, i.e., 24 hours before irradiation, at 0 hr, and at 90 min after theirradiation, we applied NAGE (total ginsenoside content: 10.5%) with different concentrations (0, 250, 500, and 1000 mg ml-1) to G0

PBL cultures obtained from each donor for another 24 h. Based on the results of trolox equivalent antioxidant capacity assay andthiobarbituric acid-malondialdehyde assay of PBL, we found that (1) at 0 Gy, increasing NAGE concentrations resulted in a trend ofincreasing TAC in PBL (p\0.001); (2) after 1 - 2 Gy irradiation, the increment of TAC level correlates with the increment of NAGEconcentrations in a linear trend (p \ 0.0001), particularly pronounced in PBL after 2 Gy exposure; (3) in the absence of NAGE,variations in baseline TAC level evaluated at different time points were insignificant; and (4) ROS levels in PBL varied inverselywith that of TAC (p\0.001). Our findings strongly indicate that NAGE increased TAC and decreased ROS in human PBL after 1 - 2Gy exposure. TAC reflects the defense mechanism against IR-induced oxidative stress in PBL. We believe that NAGE is a naturalcompound that holds potential as a radiation countermeasure not only for cancer patients receiving RT, but also for victims duringaccidental or bioterrorism exposure. This work was supported by NIH/NCCAM grant R21AT002639-01A1.

Author Disclosure: T. Lee, None; W. Wang, None; K. O’Brien, None; R. Johnke, None; T. Wang, None; R. Allison, None.

3187 Effects of Neutrophil Elastase Inhibitor on the Reduction of Radiation Pneumonitis

T. Shimbo, T. Inomata, M. Takahashi, Y. Uesugi

Japan, Takatuki-si, Japan

In this study, we irradiated the murine lung and analyzed the inhibitory effects of Sivelestat Sodium Hydrate (SSH), and Neu-trophil Elastase (NE) inhibitor, on lung injury in mice. SSH (3 mg/kg) was administered through intraperitoneal injection imme-diately, 3 hrs, 6 hrs, and 12 hrs after irradiation in groups RE-0, RE-3, RE-6, and RE-12, respectively. A control group and a groupreceiving radiation without sivelestat (group R) were also used. NE activity was measured 24h and 48h after irradiation. The lungswere simultaneously extirpated and stained with hematoxylin- eosin and an Naphthol AS-D Chloroacetate Esterase Stain (N-ASD-CLA). NE activity increased in the groups in which murine lungs were irradiated. There was no increase in NE activity in controlgroup. Among the sivelestat-administered groups, NE activity was slightly elevated in the group RE-0 and was suppressed com-pared to the group R in groups the RE-3, RE-6, and RE-12 at 24 hours after irradiation. In the irradiated groups, intra-alveolarneutrophil infiltration, perivascular edema, and alveolar wall thickness were found, but these changes were mild in the sivele-stat-administered groups. The number of N-ASDCLA-positive cells increased in Sivelestat administered groups, while group Rhad low values. This meant that SSH blocked the release of NE from the neutrophils in the irradiated lungs. NE plays an importantrole in the development of radiation-induced lung injury. Sivelestat is thus expected to decrease radiation-induced lung toxicity bysuppressing NE release from neutrophils.

Author Disclosure: T. Shimbo, None; T. Inomata, None; M. Takahashi, None; Y. Uesugi, None.

3188 Carbon Ion Beam-induced Gene Expression Profiles in Human Tumors with Different p53 Status

M. Hasegawa1, I. Asakawa1, T. Tamamoto1, C. Kajitani1, H. Okada2, E. Katayama2, S. Ishiuchi3, T. Ohno3, T. Nakano3,T. Murakami4

1Nara Medical University, Kashihara, Japan, 2Higashi Osaka City General Hospital, Higashi Osaka, Japan, 3Gunma UniversityGraduate School of Medicine, Maebashi, Japan, 4National Institute of Radiological Sciences, Chiba, Japan

Purpose/Objective(s): High LET ion beams have different biological effect on tumors compared with X-rays, and it is suggestedthat carbon ion may induce apoptosis of some tumor cells irrespective of their p53 status. The aim of this study is to investigate geneexpression profiles of human tumor cells in vivo with different p53 status in response to carbon ion beam irradiation.