The Effect of Prognostic Factors and Adjuvant Radiotherapy on Survival in Patients with High-Grade Early-Stage Endometrial Cancer: A Retrospective Clinical Study.

BACKGROUND This retrospective clinical study aimed to investigate the effect of prognostic factors and adjuvant radiotherapy in patients with high-grade early-stage endometrial cancer on overall survival (OS) and disease-free survival (DFS). MATERIAL AND METHODS The medical records of patients diagnosed with high-grade, early stage (I or II) endometrial adenocarcinoma who had received adjuvant radiotherapy after surgery were reviewed. RESULTS Seventy-nine patients included 39 patients (49.4%) with stage II endometrial cancer, 25 patients (31.6%) with histologic grade 3 tumors, and 47 patients (59.5%) with endometrial cancer showing lymphovascular space invasion (LVSI). There were 45 patients (57.0%) who received external pelvic radiotherapy with an average dose of 46.0 Gy (range, 11.2-50.4 Gy), and 34 patients (43.0%) received vaginal brachytherapy (VBT) with an average dose of 21.5 Gy (range, 10-36 Gy). Multivariate analysis showed that tumor stage (HR, 4.066; 95% CI, 1.227-13.467; p=0.022) and histologic grade (HR, 16.652; 95% CI, 4.430-62.589; p<0.001) were independent predictors for OS. Increased serum CA-125 levels (HR, 1.136; 95% CI, 0.995-1.653; p=0.047) and histologic grade (HR, 3.236; 95% CI, 1.107-15.156; p=0.015) were independent predictors for DFS. Adjuvant radiotherapy was not found to be significantly associated with improved OS (HR, 1.259; 95% CI, 0.518-3.058; p=0.612) or DFS (HR, 1.056; 95% CI, 0.994-1.123; p=0.078). CONCLUSIONS This retrospective study showed that in high-grade early-stage endometrial cancer treated with postoperative adjuvant radiotherapy, independent predictors for OS were tumor stage and grade. Adjuvant radiotherapy was not associated with improved OS or DFS.

Effect of radiation on brain tissue endothelin-1 level and tumor development.

BACKGROUND: Radiotherapy causes injury in the endothelial cells of blood vessels and the production of vasoactive amines such as endothelin-1 (ET-1). ET-1 is an important peptide in cancer development. In this study, the effects of radiation on brain tissue ET-1 level were evaluated. Is it possible to suggest a mechanism using ET-1 level in the production of this adverse effect? In this paper, the relationship between the development of brain tumors and the ET-1 level has been discussed. MATERIALS AND METHODS: Twenty-eight adult Sprague Dawley rats were used in the experiments. The rats were divided into four groups (n = 7) as follows: control group: radiation was not applied during the experiment; Group 1: Decapitated on the 1st day following radiation; Group 2: Decapitated on the 7th day following radiation; and Group 3: Decapitated on the 30th day following radiation. ET-1 levels were measured with enzyme-linked immunosorbent assay (ELISA) method. The t-test, variance analysis, and Tukey honestly significant difference (HSD) tests were used in the statistical analysis. A value of P < 0.05 was accepted as significant. RESULTS: No statistical differences were observed in the tissue ET-1 levels between the control group and other groups. According to the variance analysis and Tukey test, the differences between the groups were not significant. CONCLUSION: We observed in this study that the effects of radiation on brain tumor development or malignant transformation are not mediated by ET-1 levels. In addition, these results support the hypothesis of the fact that medical treatment with ET-1 antagonists in clinical cases receiving radiotheraphy is unnecessary.

Melatonin's protective effect on the salivary gland against ionized radiation damage in rats.

OBJECTIVES: The aim of this study was to examine the effects of melatonin on ionized radiation-induced salivary gland damage using an experimental model. MATERIALS AND METHODS: Thirty-two rats were randomized into four groups: (i) the control group (C, n = 8) that received intraperitoneal (i.p.) 0.9% NaCl; (ii) the melatonin group (M, n = 8) that received i.p. 5 mg/kg melatonin; (iii) the radiotherapy group (RT, n = 8) that underwent irradiation; (iv) the melatonin plus radiotherapy group (M+RT, n = 8) that received i.p. 5 mg/kg of melatonin, followed by irradiation 30 min later; and (v) the radiotherapy plus melatonin group (RT+M, n = 8) that received irradiation followed by i.p. 5 mg/kg of melatonin 30 min later. The medications and irradiation were administered for 5 days and the salivary glands of the rats were excised 10 days later; the histopathological changes in the salivary glands were assessed and biochemical analyses were conducted (tissue levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH), total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI)). RESULTS: Regardless of whether melatonin was administered before or after radiotherapy, melatonin decreased the radiation-induced parotid and submandibular histological damage. In addition, regardless of whether administration occurred before or after radiotherapy, melatonin decreased oxidative stress markers, such as MDA, TOS, and OSI. On the contrary, levels of antioxidative markers, such as CAT and GPx, were increased by melatonin. CONCLUSIONS: Melatonin may have a significant protective effect on salivary gland damage secondary to ionizing radiation.

Melatonin protects inner ear against radiation damage in rats.

OBJECTIVES/HYPOTHESIS: To examine the effects of N-acetyl-5-methoxytryptamine (melatonin) on radiation-induced inner ear damage. STUDY DESIGN: An experimental animal model. METHODS: Forty rats were randomized into five groups, as follows: 1) melatonin and then radiotherapy group (n = 8), which received intraperitoneal (i.p.) melatonin (5 mg/kg) followed by irradiation 30 minutes later; 2) radiotherapy and then melatonin group (n = 8), which received irradiation with i.p. melatonin (5 mg/kg) 30 minutes later; 3) melatonin group (n = 8), which received i.p. melatonin (5 mg/kg); 4) radiotherapy group (n = 8), which underwent only irradiation; 5) and the control group (n = 8), which received i.p. 0.9% NaCl. The medications and irradiation were administered for 5 days. All rats underwent the distortion product otoacoustic emission (DPOAE) test before and 10 days after the experiment. The middle ears of the rats were excised, and assessment of tissue alterations in the organs of Corti, spiral ganglions, and stria vascularis were compared among the groups. RESULTS: In the radiotherapy group, the DPOAE amplitudes at frequencies of 4000 to 6000 Hz were significantly decreased when compared with the controls. The DPOAE amplitudes both in the melatonin and then radiotherapy group and the radiotherapy and then melatonin group exhibited better values than they did in the radiotherapy group. Histopathological evidence of damage to the organs of Corti, spiral ganglions, and stria vascularis damage was markedly reduced in both these two groups when compared to the radiotherapy group. CONCLUSION: These results indicate that melatonin may have significant ameliorative effects on cochlear damage secondary to ionizing radiation.

Apricot attenuates oxidative stress and modulates of Bax, Bcl-2, caspases, NFκ-B, AP-1, CREB expression of rats bearing DMBA-induced liver damage and treated with a combination of radiotherapy.

We evaluated the ability of apricot to attenuate apoptosis and oxidative stress developed during the process of 7,12-dimethylbenz[a]anthracene (DMBA) and radiotherapy in the liver of rats bearing liver damage. Fifty female Wistar rats were divided into 7 groups; (i) normal control rats; (ii) rats fed with standard diet with apricot (20%), (ii) rats fed with standard diet and administrated 6 gray radiotherapy with Co 60 device applied to a single fraction, (iv) rats fed with standard diet and administered intraperitoneally DMBA (20mg/kg), (v) rats fed with standard diet and administered DMBA and 6 gray radiotherapy, (vi) rats fed with standard rat diet and administered DMBA and supplemented apricot, (vii) rats fed with standard diet supplemented apricot administered DMBA and radiotherapy (RT) for 6weeks. Expression of Bax, caspase 3, and glutathione activity decreased in the liver but liver expression of NF-κB, AP-1, CREB, Bcl-2 and ALT, AST, 5'NT, MDA, NO levels increased in DMBA-induced liver damage rats. In conclusion, the results suggest that apricot supplementation and irradiation given in combination, offer maximum protection against DMBA-induced hepatic carcinogenesis.

Preventive effects of resveratrol against azoxymethane induced damage in rat liver.

BACKGROUND: In recent years, due to modern lifestyles and exposure to chemical carcinogens, cancer cases are steadily increasing. From this standpoint, azoxymethane (AOM), a chemical carcinogen which causes de novo liver damage, and resveratrol, which is an antioxidant found in foods and protects against oxidative stress damage, are of interest. We here aimed to evaluate whether resveratrol could protect the liver tissues from the effects of AOM. MATERIALS AND METHODS: The study was conducted in 4 groups, each consisting of seven rats, the first receiving only AOM (2 times per week, 5 mg/kg), group 2 AOM and resveratrol (2 times a week, 20 mg/kg), group 3 assessed only as a control and group 4 administered only resveratrol. At the end of the seventh week, the rats were sacrificed. Rat liver MDA, NO, GSH levels were analyzed biochemically, as well as the tissues being evaluated histopathologically. RESULTS: MDA and NO increased in AOM group as signs of increased oxidative stress. The group concomitantly administered resveratrol was been found to be significantly decreased in MDA and NO levels and increased in GSH activity. However, there were no significant findings on histopathological evaluation. CONCLUSIONS: In the light of these results, resveratrol appears to exert protective effect on oxidative stress in the liver tissue due to deleterious effects of chemical carcinogens.

Protective effects of resveratrol on salivary gland damage induced by total body irradiation in rats.

OBJECTIVES/HYPOTHESIS: One of the most common acute side effects of irradiation is xerostomia, which results from damage to the salivary gland cells by direct ionization. Resveratrol is a natural compound with profound anti-inflammatory and antioxidant properties. The purpose of the present study was to investigate the potential protective effects of resveratrol on injury to the salivary glands of rats that were exposed to total body irradiation. STUDY DESIGN: An experimental study at the Inonu University School of Medicine. METHODS: Twenty-nine female rats were randomized into four groups: group 1, high-dose (100 mg/kg) resveratrol group (n = 7); group 2, low-dose (10 mg/kg) resveratrol group (n = 7); group 3, control (vehicle) rats (n = 7); and group 4, sham-irradiation group (n = 8). The medications were administered as single doses, and the rats were exposed to total body irradiation 24 hours after the treatment. The animals were sacrificed the following day, and the parotid and submandibular glands were excised. Salivary gland histology and the tissue levels of glutathione (GSH), nitric oxide (NO), and malondialdehyde (MDA) were investigated. RESULTS: The rats in group 1 showed significantly decreased acinar loss and less ductal damage and cell necrosis than those of the control group (P < .05). Antioxidant GSH levels were significantly increased by high doses of resveratrol treatment. The tissue activities of MDA in both the parotid and submandibular glands were significantly reduced in group 1. Low-dose resveratrol treatment did not significantly alter the tissue levels of MDA. CONCLUSIONS: Resveratrol at relatively high doses can reduce the irradiation-dependent salivary gland damage, suggesting that this natural antioxidant may be effectively used to lessen the side effects related to salivary gland dysfunction that is induced by irradiation.

Ameliorative effects of resveratrol on acute ovarian toxicity induced by total body irradiation in young adult rats.

OBJECTIVE: The purpose of this study was to investigate the ovarian protective effects of resveratrol in rats exposed to total body irradiation. DESIGN: Experimental study. SETTINGS: University hospital. PARTICIPANTS AND INTERVENTIONS: Thirty female rats were randomized into four groups: (1) control group (n = 7); (2) low-dose (10 mg/kg) resveratrol group (n = 8); (3) high-dose (100 mg/kg) resveratrol group (n =7); and (4) sham irradiation group (n = 8). The drugs were administered intraperitoneally as single doses, and the rats were exposed to total body radiation 24 h after the treatment. The animals were sacrificed the following day, and their ovaries were excised for histopathological and biochemical analysis. MAIN OUTCOME MEASURES: The ovarian follicle counts were calculated, and irradiation-dependent ovarian damage and tissue levels of antioxidant enzymes were evaluated. RESULTS: Group 2 and Group 3 showed significantly higher numbers of total follicle counts compared with Group 1 (P < 0.01). The low-dose resveratrol treatment was associated with significantly higher numbers of primary follicles than the high-dose group. The tissue activities of glutathione peroxidase (GsH-Px) and catalase (CAT) were significantly elevated in the resveratrol-treated animals. Evaluation of ovarian histology revealed no remarkable changes in fibrosis and leucocyte infiltration among the resveratrol-treated and control rats; however, vascularity was significantly reduced in the high-dose group (P = 0.014). CONCLUSION: Resveratrol attenuated irradiation-dependent ovarian damage, suggesting that this natural antioxidant is effective in reducing the follicle loss induced by ionizing radiation.