PROSPECTS FOR CREATION OF RADIOPROTECTIVE MEANS BASED ON NATURAL POLYPHENOLS AND POLYSACCHARIDES. / PERSPEKTYVY STVORENNIa ZASOBIV RADIOZAKhYSNOÏ DIÏ NA OSNOVI KOMPOZYTsII PRYRODNYKh POLIFENOL'NYKh SPOLUK I POLISAKhARYDIV.

The high level of nuclear radiation threats in the modern world determines the need to find new means of pharmacological protection of the health of military personnel and civilians from the effects of ionizing radiation. Of particular scientific interest in this aspect are natural polyphenols as a promising basis for the development of newdrugs, radiomodifiers. OBJECTIVE: Justification of the prospects of creating radioprotective agents based on compositions of plantpolyphenolic substances (PPS) and polysaccharides. MATERIAL AND METHODS: The experiments were performed on 130 laboratory white rats-male of Wistar line sexually mature weighting 180-240 g. Animals once received a total X-ray dose equivalent to 4.25 Gy. The effects ofquercetin and patulaten to the processes of reparative regeneration under conditions of X-ray irradiation andagainst the background of butadione suppression were investigated. Indicators in the study groups were compared using the Student's t-test for independent samples; the differences were considered statistically significantat p < 0.05. RESULTS: The various biological properties of quercetin, in particular, the ability to bind hydroxyl radicals, is thepotential for developing radioprotective agents based on it. At the first stage of the study, the effect of PPS andtheir compositions with polysaccharides on reparative regeneration was studied against the background of its suppression in intact and irradiated animals. With the oral administration of PPS and their compositions with pectin towhite rats, 30 minutes before the administration of butadion, an increase in the processes of reparative regeneration in the cells of the covering epitheliumof the esophagus was observed. At the same time, quercetin granulescaused the most expressive effect, which increased the statistically significant value of the mitotic index by 78.5 %in relation to the group of animals injected with butadion. At the second stage of the study, the effect of polyphenolic substances and their compositions with pectin on the processes of reparative regeneration in intact and irradiated white rats was studied on a model of linear skin wounds. The prophylactic administration of quercetin granules and the treatment of wounds with 20 % sterile quercetin gel significantly accelerated the healing process.Experimental data indicate that quercetin granules have the ability to stimulate the processes of reparative regeneration, quercetin showed the greatest efficiency with simultaneous use inside and topically. CONCLUSIONS: The research results indicate the promise of developing radioprotective drugs that can stimulatereparative regeneration processes based on compositions of plant polyphenolic substances and polysaccharides invarious qualitative and quantitative ratios.

Anastomotic complications after Ivor Lewis esophagectomy in patients treated with neoadjuvant chemoradiation are related to radiation dose to the gastric fundus.

PURPOSE: Neoadjuvant chemoradiation (CRT) is increasingly used in locally advanced esophageal cancer. Some studies have suggested that CRT results in increased surgical morbidity. We assessed the influence of CRT on anastomotic complications in a cohort of patients who underwent CRT followed by Ivor Lewis esophagectomy. PATIENTS AND METHODS: Clinical and pathologic data were collected from all patients treated with neoadjuvant CRT (36 Gy combined with 5-fluorouracil and cisplatin) followed by Ivor Lewis esophagectomy. On the radiotherapy (RT) planning computed tomography scans, normal tissue volumes were drawn encompassing the proximal esophageal region and the gastric fundus. Within these volumes, dose-volume histograms were analyzed to generate the total dose to 50% of the volume (D(50)). We studied the ability of the D(50) to predict anastomotic complications (leakage, ischemia, or stenosis). Dose limits were derived using receiver operating characteristics analysis. RESULTS: Fifty-four patients were available for analysis. RT resulted in either T or N downstaging in 51% of patients; complete pathologic response was achieved in 11%. In-hospital mortality was 5.4%, and major morbidity occurred in 36% of patients. Anastomotic complications (AC) developed in 7 patients (13%). No significant influence of the D(50) on the proximal esophagus was noted on the anastomotic complication rate. The median D(50) on the gastric fundus, however, was 33 Gy in patients with AC and 18 Gy in patients without AC (p = 0.024). Using receiver operating characteristics analysis, the D(50) limit on the gastric fundus was defined as 29 Gy. CONCLUSIONS: In patients undergoing neoadjuvant CRT followed by Ivor Lewis esophagectomy, the incidence of AC is related to the RT dose on the gastric fundus but not to the dose received by the proximal esophagus. When planning preoperative RT, efforts should be made to limit the median dose on the gastric fundus to 29 Gy with a V(30) below 40%.

Correlation between tumor-associated proteins and response to neoadjuvant treatment in patients with advanced squamous-cell esophageal cancer.

BACKGROUND: Possible predictive markers of response to neoadjuvant radiochemotherapy (NRCT) of esophageal cancer have been identified. PATIENTS AND METHODS: Patient biopsies were obtained from both tumor and normal tissue before the NRCT of locally advanced esophageal squamous cell carcinoma. Protein solutions were separated and immunoblot analysis was performed with heat shock protein (Hsp)16.2, heme-binding protein 2 (SOUL), BCL2-associated X protein (Bax), B-cell-associated leukemia protein 2 (Bcl-2) and heat shock protein 90 (Hsp90) antibodies. Following NRCT, the patients were restaged according to the Response Evaluation Criteria In Solid Tumors (RECIST). Following resections the pathological down-staging was evaluated. RESULTS: Clinical restaging revealed a response rate of 65%. Pathological examination revealed down-staging in 30% and 25% of the cases for the T and N categories respectively. Compared to the normal esophageal mucosa, a decreased expression of Hsp16.2, Hsp90 and SOUL proteins and an increased Bax/Bcl-2 ratio was found in the responding tumors. CONCLUSION: Hsp16,2, Hsp90 and SOUL expression and Bax/ Bcl-2 ratio correlates to the efficacy of NRCT and predict outcome in patients with locally advanced squamous-cell esophageal cancer.

Radiotherapy with 8-MHz radiofrequency-capacitive regional hyperthermia for stage III non-small-cell lung cancer: the radiofrequency-output power correlates with the intraesophageal temperature and clinical outcomes.

PURPOSE: To assess the efficacy of radiotherapy (RT) combined with regional hyperthermia (HT) guided by radiofrequency (RF)-output power and intraesophageal temperature and evaluate the potential contribution of HT to clinical outcomes in patients with Stage III non-small-cell lung cancer (NSCLC). METHODS AND MATERIALS: Thirty-five patients with Stage III NSCLC treated with RT plus regional HT were retrospectively analyzed. Twenty-two of the 35 patients underwent intraesophageal temperature measurements. Patients with subcutaneous fat of 2.5 cm or greater, older age, or other serious complications did not undergo this therapy. The 8-MHz RF-capacitive heating device was applied, and in all patients, both the upper and lower electrodes were 30 cm in diameter, placed on opposite sides of the whole thoracic region, and treatment posture was the prone position. The HT was applied within 15 minutes after RT once or twice a week. RESULTS: All thermal parameters, minimum, maximum, and mean of the four intraesophageal temperature measurements at the end of each session and the proportion of the time during which at least one of the four intraesophageal measurements was 41 degrees C or higher in the total period of each session of HT, of the intraesophageal temperature significantly correlated with median RF-output power. Median RF-output power (>/=1,200 W) was a statistically significant prognostic factor for overall, local recurrence-free, and distant metastasis-free survival. CONCLUSIONS: The RT combined with regional HT using a higher RF-output power could contribute to better clinical outcomes in patients with Stage III NSCLC. The RF-output power thus may be used as a promising parameter to assess the treatment of deep regional HT if deep heating using this device is performed with the same size electrodes and in the same body posture.

Esophageal cancer. A prospective phase II study of concomitant-boost external-beam chemoradiation with a top-up endoluminal boost.

PURPOSE: To present the results of a prospective phase II study in esophageal carcinoma. PATIENTS AND METHODS: Patients received single doses of 1.8 Gy up to 27 Gy, then concomitant boost to a total of 50.4 Gy (PTV2 [planning target volume], single dose 1.8 Gy) and 64.8 Gy (PTV1, single dose 1.2 Gy in the morning and 1.8 Gy in the afternoon) concurrently with 800 mg/m(2)/d 5-fluorouracil and 20 mg/m(2)/d cisplatin (weeks 1 and 5). High-dose-rate brachytherapy (2-3 x 6 Gy) on Fridays of weeks 4-6 used a customized applicator facilitating central placement and circumferential dose homogeneity. RESULTS: 50 patients with squamous cell carcinoma (90%) or adenocarcinoma and mostly advanced tumor stage were treated (82% T3/T4 and 70% N1). Median overall survival (median OS 16 months; 1-year-OS 61%; 2-year OS 29%) was significantly longer for patients without nodal disease (35 vs. 11 months; p = 0.01). Hematotoxicity was grade 3 in 11/50, and grade 4 in 1/50 patients. Four percent of higher-grade nausea or vomiting occurred. Esophageal late toxicity was grade 3 in 9/50 patients, and grade 4 in 2/50 patients. CONCLUSION: Survival was excellent especially for patients without nodal disease in this dose-intensified schedule with acceptable tolerability.

Radioprotective effects of amifostine on acute and chronic esophageal injury in rodents.

PURPOSE: This study was performed to evaluate the protective benefit of amifostine against esophageal injury from fractionated radiation in a rodent model. METHODS: Fractionated or sham esophageal irradiation was administered to Fisher-344 rats for 5 consecutive daily fractions of 9 Gy using 150 kV X-rays. Animals received an intraperitoneal injection of amifostine or placebo 30 min before each fraction. Histopathologic analyses for mucosal thickness, submucosal collagen deposition, activation of macrophages, oxidative stress and expression/activation of integrinalphavbeta6 and transforming growth factor (TGF)-beta were performed 5 days and 10 weeks after irradiation. RESULTS: Pre-RT mean mucosal thickness was 35 microm in both the placebo and the amifostine groups. Five days post-RT, mean mucosal thicknesses were 30 microm in the placebo group versus 37 microm in the amifostine group (p = 0.024). At 10 weeks post-RT, the group receiving amifostine experienced a significant decrease in tunica muscularis damage (p = 0.002), submucosal collagen deposition (p = 0.027), and macrophage accumulation (p = 0.026) when compared with the placebo group. The levels of immunoreactivity for oxidative stress, TGF-beta, and integrinalphavbeta6 were significantly decreased 10 weeks post-RT in the group receiving amifostine treatment compared with placebo group. CONCLUSIONS: This study demonstrates that amifostine given before each radiation fraction protects against acute and chronic esophageal injury in a rodent model. Protection of the mucosal epithelium integrity by amifostine prevents integrinalphavbeta6 expression which reduces TGF-beta activation and subsequent development of chronic esophageal injury in this model. Further investigation is necessary to determine the clinical relevance of these findings.

Different susceptibility of cells of porcine skin and internal organs to ultraviolet A-induced breaking of nuclear DNA.

There is a continuously growing interest in medical applications of ultraviolet radiation (UV-A and long-wavelength UV-B) especially for laser surgery, phototherapy and photodiagnostics of human internal organs. UV-B and UV-A radiation is potentially mutagenic, however, there has been very little information published to date concerning the significance of possible deleterious action of such photons on cells of internal tissues. The aim of this study is to compare the sensitivities of skin cells to those of internal organs upon exposure to UV-A. To assess this sensitivity we have determined the UV-A dose-dependent frequency of nuclear DNA breaks detected with the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling (TUNEL) technique. The materials for the study were macroscopic samples of porcine skin, colon and esophagus. The UV-A dose ranged from 0.1 to 1000 mJ/cm2, which is similar to doses received by cells in regions examined with laser-induced fluorescence or by cells surrounding areas subject to a laser ablation. To reduce the influence of DNA repair processes the tissue samples were kept at a low temperature during the irradiation and were deep frozen immediately after completing the irradiation procedure. The cells of the internal organs are much more susceptible to UV-A-induced breaking of DNA than the skin cells. The percentage fractions and the spatial distributions of the damaged cells and the characteristics of the UV-A dose dependence seem to vary by type of internal organ.

[Effects of Fuzheng Yiliu Granule on expression of CD44v6 and nm23-H1 in esophageal carcinoma treated with radiotherapy].

OBJECTIVE: To evaluate the effects of Fuzheng Yiliu Granule on the expression of CD44v6 and nm23-H1 in esophageal carcinoma treated with radiotherapy. METHODS: Sixty-three cases of esophageal carcinoma were randomly divided into two groups: Fuzheng Yiliu Granule plus radiotherapy treated group (n=30) and radiotherapy treated group (n=33). The carcinoma specimens were obtained through endoscopic biopsy before and after twenty-one days of treatment. The expression of CD44v6 and nm23-H1 was determined in the sixty-three specimens of esophageal carcinoma by immunohistochemical SABC methods. RESULTS: After twenty-one days of treatment, the positive rates of CD44v6 in the Fuzheng Yiliu Granule plus radiotherapy treated group and the radiotherapy treated group were 40.0% and 69.7%, respectively, and there was significant difference between the two groups (P<0.05). The positive rates of nm23-H1 in the Fuzheng Yiliu Granule plus radiotherapy treated group and the radiotherapy treated group were 20.0% and 21.2%, respectively, and the difference was not significant between the two groups (P>0.05). CONCLUSION: Fuzheng Yiliu Granule can lower the expression of CD44v6 in esophageal carcinoma, and may prevent infiltration and lymph node metastasis of esophageal carcinoma.

Temporally and spectrally resolved fluorescence spectroscopy for the detection of high grade dysplasia in Barrett's esophagus.

BACKGROUND AND OBJECTIVES: Temporal and spectral fluorescence spectroscopy can identify adenomatous colonic polyps accurately. In this study, these techniques were examined as a potential means of improving the surveillance of high grade dysplasia (HGD) in Barrett's esophagus (BE). STUDY DESIGN/MATERIALS AND METHODS: Using excitation wavelengths of 337 and 400 nm, 148 fluorescence spectra, and 108 transient decay profiles (at 550 +/- 20 nm) were obtained endoscopically in 37 patients. Corresponding biopsies were collected and classified as carcinoma, HGD, or low risk tissue (LRT) [non-dysplastic BE, indefinite for dysplasia (IFD), and low grade dysplasia (LGD)]. Diagnostic algorithms were developed retrospectively using linear discriminant analysis (LDA) to separate LRT from HGD. RESULTS: LDA produced diagnostic algorithms based solely on spectral data. Moderate levels of sensitivity (Se) and specificity (Sp) were obtained for both 337 nm (Se = 74%, Sp = 67%) and 400 nm (Se = 74%, Sp = 85%) excitation. CONCLUSIONS: In the diagnosis of HGD in BE, steady-state fluorescence was more effective than time-resolved data, and excitation at 400 nm excitation was more effective than 337 nm. While fluorescence-targeted biopsy is approaching clinical usefulness, increased sensitivity to dysplastic changes-possibly through modification of system parameters-is needed to improve accuracy levels.

Radiotherapy with high dose rate brachytherapy boost and concomitant chemotherapy for Stages IIB and III esophageal carcinoma: results of a pilot study.

PURPOSE: Radiotherapy (RT) and concomitant chemotherapy (CT) is the standard treatment for non resectable esophageal cancer. Usual total radiation dose is 50 Gy. In order to enhance local control rate a Phase II study was initiated to evaluate the feasibility of a combined treatment with an external radiation dose of 60 Gy and three cycles of concomitant CT, using the three main active drugs (CDDP, 5 FU and MMC), followed by a high dose rate (HDR) brachytherapy delivering 10 Gy. METHODS AND MATERIALS: Fifty-three patients, 48 men and 5 women, were entered in this study. Stages were evaluated with CT scan and with endoscopic sonography. Fifteen were Stage IIB, 38 Stage III. Treatment consisted of conventional fractionated RT to a total dose of 60 Gy delivered with 2 Gy per fraction, one fraction per day and five fractions per week. The CT regimen was a combination of Cisplatinum (CDDP) 20 mg/m2 and 5 Fluorouracil (5FU) 600 mg/m2 continuous infusion, from days 1-4 Mitomycin C (MMC) was given at 6 mg/m2 on day 1. Three cycles were administered on days 1, 22, and 43. Brachytherapy was delivered one week after the end of external radiation therapy. RESULTS: Full radiation therapy dose was delivered for 94% of the patients. CT compliance, evaluated on the mean relative dose-intensity was 85% for CDDP, 81% for 5FU and 51% for MMC. Overall grade 3 and 4 WHO toxicity rates were 23% and 7%, respectively. Haematologic toxicity was the most limiting factor. One patient died from treatment toxicity. Local control rate at one year was 74%. Three-year actuarial survival rate was 27%. Distant metastasis was the main cause of treatment failure. Swallowing score was good for 75% of the patients. Stage, performance status and weight loss were prognostic factors. CONCLUSION: This regimen with high dose RT, HDR brachytherapy and concomitant CT is feasible; however, a high level of haematologic toxicity was observed with the CDDP, 5FU and MMC regimen. Despite a poor compliance with CT, treatment results are very encouraging for patients with locally advanced disease.

Carcinoma of the esophagus treated with radical chemoradiation 19 years after irradiation for recurrent breast cancer.

Prior irradiation to a site is a relative and often absolute contraindication to further irradiation because the tolerance dose of normal tissues is usually exceeded and therefore the risk of serious long-term side-effects is high. This case report describes radical salvage chemoradiation for an esophageal carcinoma in a patient who had prior high-dose neck and chest wall irradiation for the management of a breast cancer 19 years previously.

Assessment of apoptosis in oesophageal carcinoma preoperatively treated by chemotherapy and radiotherapy.

Apoptosis, programmed cell death, was immunohistochemically determined in 55 samples of oesophageal squamous cell carcinoma using the BM1 Mab. Sections from patients not treated (group 1, n = 12) or preoperatively treated by chemotherapy (group 2, n = 11), radiation (group 3, n = 13) or both (group 4, n = 8), and 11 additional cases of high-grade dysplasia or early cancer were examined. Most of the apoptotic cells were BM1-positive and checked by TUNEL proved to be nick end positive. They accounted for 7 (11%), 19 (29%), 21 (32%) and 26 (38%) cells per field in those 4 groups respectively. Chemotherapy and/or radiation significantly increased the number of apoptotic cells as compared to controls (p = 0.029 and p = 0.029, respectively). To assess the implications of the oncogene expression in the apoptotic pathway, additional section stained with bcl2 and p53 were negative for bcl2 and were positive for p53 in 16 samples (37%). Overall, positive cases for p53 mutation showed a significantly decreased incidence of apoptotic cells (p = 0.03). These results suggest that in situ assessment of apoptotic response better correlates to the apoptosis induced by radiation than that by chemotherapy, that abnormalities of the p53 protein decrease the apoptotic response in oesophageal carcinoma, and that immunohistochemical analysis of p53 protein helps to determine the sensitivity to these anticancer agents.

Thermodamage, thermosensitivity and thermotolerance of normal swine oesophagus.

The normal swine oesophagus was heated using an intracavity microwave radiator for 30 min at 45, 46, 47, 48 and 49 degrees C. The animals were sacrificed 48 h or 30 days later. The degree of heat injury was evaluated on an histological score system with a maximum possible damage score of 100 per cent. The acute heat injury (48 h after heating) at these temperatures was 2, 17, 40, 50 and 67 per cent respectively. The main feature of acute heat damage was degenerative necrosis or thrombosis of blood vessels at the oesophageal wall. This occurred only in one out of nine cases at 45 and 46 degrees C heating, but in seven out of nine cases at 48 and 49 degrees C. The main feature of late heat damage was fibrosis. The score of chronic damage for the above groups was 12, 23, 30, 34 and 51 per cent, respectively. When animals were preheated at 44 degrees C for 30 min and then reheated at 45-49 degrees C 4 h later, we found that preheating could provide about 2 degrees C protection. From the above data, we suggest that 45 degrees C and 30 min heating is a safe dose for normal oesophageal tissue.