Immunization with Eimeria ninakohlyakimovae-live attenuated oocysts protect goat kids from clinical coccidiosis.

Caprine coccidiosis, affecting mainly young goat kids around the weaning period, is worldwide the most important disease in the goat industry. Control of caprine coccidiosis is increasingly hampered by resistances developed against coccidiostatic drugs leading to an enhanced need for anticoccidial vaccines. In the current study we conducted an oral immunization trial with live attenuated sporulated Eimeria ninakohlyakimovae oocysts. Sporulated E. ninakohlyakimovae oocysts were attenuated by X-irradiation technique. The experimental design included a total of 18 goat kids divided into the following groups: (i) animals immunized with attenuated E. ninakohlyakimovae oocysts at 5 weeks of age and challenged 3 weeks later with non-irradiated homologous oocysts (group 1); (ii) animals infected with non-attenuated E. ninakohlyakimovae oocysts at 5 weeks of age and challenged 3 weeks later with non-attenuated homologous oocysts (group 2); (iii) animals primary-infected with untreated E. ninakohlyakimovae oocysts at 8 weeks of age (control of the challenge infection, group 3); (iv) non-infected control animals (group 4). Goat kids immunized with live attenuated E. ninakohlyakimovae oocysts (group 1) excreted significantly less oocysts in the faeces (95.3% reduction) than kids infected with non-attenuated ones (group 2). Furthermore, immunization with live but attenuated oocysts resulted in ameliorated clinical coccidiosis compared to goat kids infected with untreated oocysts (group 2) and resulted in equally reduced signs of coccidiosis after challenge infection compared to acquired immunity driven by non-attenuated oocysts. Overall, the present study demonstrates for the first time that live attenuated E. ninakohlyakimovae oocysts orally administered showed almost no pathogenicity but enough immunogenicity in terms of immunoprotection. Importantly, vaccinated animals still shed low amounts of oocysts, guaranteeing environmental contamination and consecutive booster infections to sustain ongoing immunity.

Common genomic signaling among initial DNA damage and radiation-induced apoptosis in peripheral blood lymphocytes from locally advanced breast cancer patients.

PURPOSE: To investigate the genomic signaling that defines sensitive lymphocytes to radiation and if such molecular profiles are consistent with clinical toxicity; trying to disclose the radiobiology mechanisms behind these cellular processes. PATIENTS AND METHODS: Twelve consecutive patients suffering from locally advanced breast cancer and treated with high-dose hyperfractionated radiotherapy were recruited. Initial DNA damage was measured by pulsed-field gel electrophoresis and radiation-induced apoptosis was measured by flow cytometry. Gene expression was assessed by DNA microarray. RESULTS: Thirty-four constitutive genes segregated patients with lower DNA-double strand break from those patients with higher DNA-double strand break (p < 0.01). Forty-two genes segregated patients according to radiation-induced apoptosis (p < 0.01). We found common canonical pathways and common biological processes significantly regulated between both set of genes. CONCLUSION: We introduced new data in the field of molecular genomics regarding to the relation established between radiation toxicity and these predictive factors to radiation injury.

In vitro synergistic interaction between DTA0100 and radiation in human cancer cell lines.

DTA0100 is a new catalytic inhibitor of the human DNA topoisomerase IIα that induces G2/M phase cell cycle arrest in human solid tumor cells lines from various malignancies. In our study, we investigated the effectiveness of the combined treatment of ionizing radiation with DTA0100 on the survival of three representative human solid tumor cell lines: HeLa (cervix), WiDr (colon) and SW1573 (non-small cell lung cancer). The concomitant treatment of DTA0100 and irradiation showed a synergistic and antagonistic effect in the three cell lines tested. A synergistic cytotoxic effect of the combination of DTA0100 and radiation was confirmed by the median drug effect analysis method. It was found that in those protocols where the drug was administered after radiation the most synergistic effect was achieved. Our study constitutes the first in vitro evidence for synergistic effects between DTA0100 and radiation. This combination therapy might thus be expected to be more effective than either treatment alone in patients with cervical, colon and non-small cell lung cancer cells.

Prediction of normal tissue toxicity as part of the individualized treatment with radiotherapy in oncology patients.

Normal tissue toxicity caused by radiotherapy conditions the success of the treatment and the quality of life of patients. Radiotherapy is combined with surgery in both the preoperative or postoperative setting for the treatment of most localized solid tumour types. Furthermore, radical radiotherapy is an alternative to surgery in several tumour locations. The possibility of predicting such radiation-induced toxicity would make possible a better treatment schedule for the individual patient. Radiation-induced toxicity is, at least in part, genetically determined. From decades, several predictive tests have been proposed to know the individual sensitivity of patients to the radiotherapy schedules. Among them, initial DNA damage, radiation-induced apoptosis, gene expression profiles, and gene polymorphisms have been proposed. We report here an overview of the main studies regarding to this field. Radiation-induced apoptosis in peripheral blood lymphocytes seem to be the most promising assay tested in prospective clinical trials, although they have to be validated in large clinical studies. Other promising assays, as those related with single nucleotide polymorphisms, need to be validated as well.

IGF-1R expression predicts clinical outcome in patients with locally advanced oral squamous cell carcinoma.

To assess the expression of IGF-1R in oral cavity squamous cell carcinoma patients, to explore its relation with clinical and pathologic prognostic factors and its role in predicting clinical outcome. One hundred and thirty-one consecutive patients suffering from oral cavity squamous cell carcinoma were included in this study from July 1989 to April 2005. Follow-up was closed in May 2010. The mean follow-up for survivors was 110.26±47.42 months. Patients were staged following the TNM classification. Patients in tumour stages I and II were referred to surgery. Patients in stages III-IV were referred to postoperative radiotherapy. Radiation therapy was administered up to a mean dose of 62.13±7.74 Gy in 1.8-2 Gy fractions. IGF-1R expression was studied by immunohistochemistry in paraffin-embedded tumour tissue. IGF-1R was expressed in 101 patients (77.1%). IGF-1R expression was related to tumour grade (P=0.012). Tumour stage was the most important prognostic factor for survival. Low (negative and fairly) IGF-1R tumour expression was correlated to better long-term Local Disease Free Survival (P=0.016), Disease-Free Survival (P=0.029), and Survival (P=0.009) in patients achieving tumour stages III-IV. Low IGF-1R expression was related to better long-term control in patients suffering locally advanced oral carcinoma.

Combined low initial DNA damage and high radiation-induced apoptosis confers clinical resistance to long-term toxicity in breast cancer patients treated with high-dose radiotherapy.

BACKGROUND: Either higher levels of initial DNA damage or lower levels of radiation-induced apoptosis in peripheral blood lymphocytes have been associated to increased risk for develop late radiation-induced toxicity. It has been recently published that these two predictive tests are inversely related. The aim of the present study was to investigate the combined role of both tests in relation to clinical radiation-induced toxicity in a set of breast cancer patients treated with high dose hyperfractionated radical radiotherapy. METHODS: Peripheral blood lymphocytes were taken from 26 consecutive patients with locally advanced breast carcinoma treated with high-dose hyperfractioned radical radiotherapy. Acute and late cutaneous and subcutaneous toxicity was evaluated using the Radiation Therapy Oncology Group morbidity scoring schema. The mean follow-up of survivors (n = 13) was 197.23 months. Radiosensitivity of lymphocytes was quantified as the initial number of DNA double-strand breaks induced per Gy and per DNA unit (200 Mbp). Radiation-induced apoptosis (RIA) at 1, 2 and 8 Gy was measured by flow cytometry using annexin V/propidium iodide. RESULTS: Mean DSB/Gy/DNA unit obtained was 1.70 ± 0.83 (range 0.63-4.08; median, 1.46). Radiation-induced apoptosis increased with radiation dose (median 12.36, 17.79 and 24.83 for 1, 2, and 8 Gy respectively). We observed that those "expected resistant patients" (DSB values lower than 1.78 DSB/Gy per 200 Mbp and RIA values over 9.58, 14.40 or 24.83 for 1, 2 and 8 Gy respectively) were at low risk of suffer severe subcutaneous late toxicity (HR 0.223, 95%CI 0.073-0.678, P = 0.008; HR 0.206, 95%CI 0.063-0.677, P = 0.009; HR 0.239, 95%CI 0.062-0.929, P = 0.039, for RIA at 1, 2 and 8 Gy respectively) in multivariate analysis. CONCLUSIONS: A radiation-resistant profile is proposed, where those patients who presented lower levels of initial DNA damage and higher levels of radiation induced apoptosis were at low risk of suffer severe subcutaneous late toxicity after clinical treatment at high radiation doses in our series. However, due to the small sample size, other prospective studies with higher number of patients are needed to validate these results.

BCL-2, in combination with MVP and IGF-1R expression, improves prediction of clinical outcome in complete response cervical carcinoma patients treated by radiochemotherapy.

OBJECTIVES: To investigate whether BCL-2 expression would improve MVP/IGF-1R prediction of clinical outcome in cervix carcinoma patients treated by radiochemotherapy, and suggest possible mechanisms behind this effect. METHODS: Fifty consecutive patients, who achieved complete response to treatment, from a whole series of 60 cases suffering from non-metastatic localized cervical carcinoma, were prospectively included in this study from July 1999 to December 2003. Follow-up was closed in January 2011. All patients received pelvic radiation (45-64.80 Gy in 1.8-2 Gy fractions) with concomitant cisplatin at 40 mg/m2/week doses followed by brachytherapy. Oncoprotein expression was studied by immunohistochemistry in paraffin-embedded tumour tissue. RESULTS: No relation was found between BCL-2 and clinicopathological variables. High MVP/IGF-1R/BCL-2 tumour expression was strongly related to poor local and regional disease-free survival (P<0.0001), distant disease-free survival (P=0.010), disease-free survival (P<0.0001), and cause-specific survival (P<0.0001). NHEJ repair protein Ku70/80 expression was significantly repressed in tumours overexpressing all three oncoproteins (P=0.047). No differences were observed in proliferation (Ki67 expression) or P53 alteration. CONCLUSIONS: BCL-2, MVP, and IGF-1R overexpression were related to poorer clinical outcome in cervical cancer patients who achieved clinical complete response to radiochemotherapy. The NHEJ repair protein Ku70/80 expression could be involved in the regulation of these oncoproteins.

Role of CD4 and CD8 T-lymphocytes, B-lymphocytes and Natural Killer cells in the prediction of radiation-induced late toxicity in cervical cancer patients.

PURPOSE: To analyse the role of in vitro radio-induced apoptosis of lymphocyte subpopulations as predictive test for late effects in cervical cancer patients treated with radiotherapy. METHODS AND MATERIALS: Ninety-four consecutive patients and four healthy controls were included in the study. Toxicity was evaluated using the Late Effects Normal Tissue-Subjective, Objective, Management, and Analytic (LENT-SOMA) scale. Peripheral blood lymphocyte subpopulations were isolated and irradiated at 0, 1, 2 and 8 Gy, and then collected 24, 48 and 72 h after irradiation. Apoptosis was measured by flow cytometry. RESULTS: Radiation-induced apoptosis increased with radiation dose and time of incubation, and data fitted to a semi-logarithmic model defined by two constants: α (percentage of spontaneous cell death) and ß (percentage of cell death induced at a determined radiation dose). Higher ß values in cytotoxic T-lymphocytes (CD8) and bone cells (B-lymphocytes) were observed in patients with low bowel toxicity (hazard ratio (HR) = 0.96, p = 0.002 for B-cells); low rectal toxicity (HR = 0.96, p = 0.020; HR = 0.93, p = 0.05 for B and CD8 subpopulations respectively); low urinary toxicity (HR = 0.93, p = 0.003 for B-cells) and low sexual toxicity (HR = 0.93, p = 0.010 for CD8-cells). CONCLUSIONS: Radiation-induced CD8 T-lymphocytes and, for the first time, B-lymphocytes apoptosis can predict differences in late toxicity in cervical cancer patients.

Radiation induced apoptosis and initial DNA damage are inversely related in locally advanced breast cancer patients.

BACKGROUND: DNA-damage assays, quantifying the initial number of DNA double-strand breaks induced by radiation, have been proposed as a predictive test for radiation-induced toxicity. Determination of radiation-induced apoptosis in peripheral blood lymphocytes by flow cytometry analysis has also been proposed as an approach for predicting normal tissue responses following radiotherapy. The aim of the present study was to explore the association between initial DNA damage, estimated by the number of double-strand breaks induced by a given radiation dose, and the radio-induced apoptosis rates observed. METHODS: Peripheral blood lymphocytes were taken from 26 consecutive patients with locally advanced breast carcinoma. Radiosensitivity of lymphocytes was quantified as the initial number of DNA double-strand breaks induced per Gy and per DNA unit (200 Mbp). Radio-induced apoptosis at 1, 2 and 8 Gy was measured by flow cytometry using annexin V/propidium iodide. RESULTS: Radiation-induced apoptosis increased in order to radiation dose and data fitted to a semi logarithmic mathematical model. A positive correlation was found among radio-induced apoptosis values at different radiation doses: 1, 2 and 8 Gy (p < 0.0001 in all cases). Mean DSB/Gy/DNA unit obtained was 1.70 ± 0.83 (range 0.63-4.08; median, 1.46). A statistically significant inverse correlation was found between initial damage to DNA and radio-induced apoptosis at 1 Gy (p = 0.034). A trend toward 2 Gy (p = 0.057) and 8 Gy (p = 0.067) was observed after 24 hours of incubation. CONCLUSIONS: An inverse association was observed for the first time between these variables, both considered as predictive factors to radiation toxicity.

Prediction of clinical toxicity in locally advanced head and neck cancer patients by radio-induced apoptosis in peripheral blood lymphocytes (PBLs).

Head and neck cancer is treated mainly by surgery and radiotherapy. Normal tissue toxicity due to x-ray exposure is a limiting factor for treatment success. Many efforts have been employed to develop predictive tests applied to clinical practice. Determination of lymphocyte radio-sensitivity by radio-induced apoptosis arises as a possible method to predict tissue toxicity due to radiotherapy. The aim of the present study was to analyze radio-induced apoptosis of peripheral blood lymphocytes in head and neck cancer patients and to explore their role in predicting radiation induced toxicity. Seventy nine consecutive patients suffering from head and neck cancer, diagnosed and treated in our institution, were included in the study. Toxicity was evaluated using the Radiation Therapy Oncology Group scale. Peripheral blood lymphocytes were isolated and irradiated at 0, 1, 2 and 8 Gy during 24 hours. Apoptosis was measured by flow cytometry using annexin V/propidium iodide. Lymphocytes were marked with CD45 APC-conjugated monoclonal antibody. Radiation-induced apoptosis increased in order to radiation dose and fitted to a semi logarithmic model defined by two constants: alpha and beta. Alpha, as the origin of the curve in the Y axis determining the percentage of spontaneous cell death, and beta, as the slope of the curve determining the percentage of cell death induced at a determined radiation dose, were obtained. beta value was statistically associated to normal tissue toxicity in terms of severe xerostomia, as higher levels of apoptosis were observed in patients with low toxicity (p = 0.035; Exp(B) 0.224, I.C.95% (0.060-0.904)). These data agree with our previous results and suggest that it is possible to estimate the radiosensitivity of peripheral blood lymphocytes from patients determining the radiation induced apoptosis with annexin V/propidium iodide staining. beta values observed define an individual radiosensitivity profile that could predict late toxicity due to radiotherapy in locally advanced head and neck cancer patients. Anyhow, prospective studies with different cancer types and higher number of patients are needed to validate these results.

Prediction of clinical toxicity in localized cervical carcinoma by radio-induced apoptosis study in peripheral blood lymphocytes (PBLs).

BACKGROUND: Cervical cancer is treated mainly by surgery and radiotherapy. Toxicity due to radiation is a limiting factor for treatment success. Determination of lymphocyte radiosensitivity by radio-induced apoptosis arises as a possible method for predictive test development. The aim of this study was to analyze radio-induced apoptosis of peripheral blood lymphocytes. METHODS: Ninety four consecutive patients suffering from cervical carcinoma, diagnosed and treated in our institution, and four healthy controls were included in the study. Toxicity was evaluated using the Lent-Soma scale. Peripheral blood lymphocytes were isolated and irradiated at 0, 1, 2 and 8 Gy during 24, 48 and 72 hours. Apoptosis was measured by flow cytometry using annexin V/propidium iodide to determine early and late apoptosis. Lymphocytes were marked with CD45 APC-conjugated monoclonal antibody. RESULTS: Radiation-induced apoptosis (RIA) increased with radiation dose and time of incubation. Data strongly fitted to a semi logarithmic model as follows: RIA = betaln(Gy) + alpha. This mathematical model was defined by two constants: alpha, is the origin of the curve in the Y axis and determines the percentage of spontaneous cell death and beta, is the slope of the curve and determines the percentage of cell death induced at a determined radiation dose (beta = DeltaRIA/Deltaln(Gy)). Higher beta values (increased rate of RIA at given radiation doses) were observed in patients with low sexual toxicity (Exp(B) = 0.83, C.I. 95% (0.73-0.95), p = 0.007; Exp(B) = 0.88, C.I. 95% (0.82-0.94), p = 0.001; Exp(B) = 0.93, C.I. 95% (0.88-0.99), p = 0.026 for 24, 48 and 72 hours respectively). This relation was also found with rectal (Exp(B) = 0.89, C.I. 95% (0.81-0.98), p = 0.026; Exp(B) = 0.95, C.I. 95% (0.91-0.98), p = 0.013 for 48 and 72 hours respectively) and urinary (Exp(B) = 0.83, C.I. 95% (0.71-0.97), p = 0.021 for 24 hours) toxicity. CONCLUSION: Radiation induced apoptosis at different time points and radiation doses fitted to a semi logarithmic model defined by a mathematical equation that gives an individual value of radiosensitivity and could predict late toxicity due to radiotherapy. Other prospective studies with higher number of patients are needed to validate these results.

Severe hypoxia induces chemo-resistance in clinical cervical tumors through MVP over-expression.

Oxygen molecule modulates tumour response to radiotherapy. Higher radiation doses are required under hypoxic conditions to induce cell death. Hypoxia may inhibit the non-homologous end-joining DNA repair through down regulating Ku70/80 expression. Hypoxia induces drug resistance in clinical tumours, although the mechanism is not clearly elucidated. Vaults are ribonucleoprotein particles with a hollow barrel-like structure composed of three proteins: major vault protein (MVP), vault poly(ADP-ribose) polymerase, and telomerase associated protein-1 and small untranslated RNA. Over-expression of MVP has been associated with chemotherapy resistance. Also, it has been related to poor outcome in patients treated with radiotherapy alone. The aim of the present study was to assess the relation of Major Vault Protein expression and tumor hypoxia in clinical cervical tumors. MVP, p53 and angiogenesis, together with tumor oxygenation, were determined in forty-three consecutive patients suffering from localized cervix carcinoma. High MVP expression was related to severe hypoxia compared to low MVP expressing tumors (p = 0.022). Tumors over-expressing MVP also showed increased angiogenesis (p = 0.003). Besides it, in this study we show for the first time that severe tumor hypoxia is associated with high MVP expression in clinical cervical tumors. Up-regulation of MVP by hypoxia is of critical relevance as chemotherapy is currently a standard treatment for those patients. From our results it could be suggested that hypoxia not only induces increased genetic instability, oncogenic properties and metastatization, but through the correlation observed with MVP expression, another pathway of chemo and radiation resistance could be developed.

Constitutive gene expression profile segregates toxicity in locally advanced breast cancer patients treated with high-dose hyperfractionated radical radiotherapy.

Breast cancer patients show a wide variation in normal tissue reactions after radiotherapy. The individual sensitivity to x-rays limits the efficiency of the therapy. Prediction of individual sensitivity to radiotherapy could help to select the radiation protocol and to improve treatment results. The aim of this study was to assess the relationship between gene expression profiles of ex vivo un-irradiated and irradiated lymphocytes and the development of toxicity due to high-dose hyperfractionated radiotherapy in patients with locally advanced breast cancer. Raw data from microarray experiments were uploaded to the Gene Expression Omnibus Database http://www.ncbi.nlm.nih.gov/geo/ (GEO accession GSE15341). We obtained a small group of 81 genes significantly regulated by radiotherapy, lumped in 50 relevant pathways. Using ANOVA and t-test statistical tools we found 20 and 26 constitutive genes (0 Gy) that segregate patients with and without acute and late toxicity, respectively. Non-supervised hierarchical clustering was used for the visualization of results. Six and 9 pathways were significantly regulated respectively. Concerning to irradiated lymphocytes (2 Gy), we founded 29 genes that separate patients with acute toxicity and without it. Those genes were gathered in 4 significant pathways. We could not identify a set of genes that segregates patients with and without late toxicity. In conclusion, we have found an association between the constitutive gene expression profile of peripheral blood lymphocytes and the development of acute and late toxicity in consecutive, unselected patients. These observations suggest the possibility of predicting normal tissue response to irradiation in high-dose non-conventional radiation therapy regimens. Prospective studies with higher number of patients are needed to validate these preliminary results.

Major vault protein may affect nonhomologous end-joining repair and apoptosis through Ku70/80 and bax downregulation in cervical carcinoma tumors.

PURPOSE: We investigated the relationship between major vault protein (MVP) expression, the nonhomologous end-joining (NHEJ) repair gene Ku70/80, and related genes involved in the regulation of apoptosis and proliferation to shed light on the possible causes of genetic instability, tumor progression, and resistance to oncologic treatment in patients with clinical cervical cancer. METHODS AND MATERIALS: One hundred sixteen consecutive patients with localized cervix carcinoma were prospectively included in this study from July 1997 to Dec 2003. Patients were staged according to the tumor, node, metastasis (TNM) classification. Forty patients had Stage I disease, 45 had Stage II, and 31 had Stage III/IVA. Most patients had squamous tumors (98 cases) and Grades II (52 cases) and III (45 cases) carcinomas. Expression of MVP, Ku70/80, Insulin-Like Growth Factor-1 receptor (IGF-1R), BCL2-associated X protein (BAX), B-cell CLL/lymphoma 2 (BCL-2), p53, and Ki67 was studied by using immunohistochemistry in paraffin-embedded tumor tissue. RESULTS: Tumors overexpressing MVP (65 of 116 cases) showed low levels of Ku70/80 (p = 0.013) and BAX expression (p < 0.0001). Furthermore, low Ku70/80 expression was strongly related to suppressed BAX (p < 0.001) and, to a lesser extent, upregulated BCL-2 (p = 0.042), altered p53 (p = 0.038), and increased proliferation (p = 0.002). CONCLUSION: We hypothesize that an early regulatory mechanism favors homologous or NHEJ repair at first, mediated by vaults along with other factors yet to be elucidated. If vaults are overexpressed, NHEJ repair may be suppressed by means of several mechanisms, with resultant genomic instability. These mechanisms may be associated with the decision of damaged cells to survive and proliferate, favoring tumor progression and reducing tumor response to oncologic treatment through the development of resistant cell phenotypes. Additional clinical studies are necessary to test this hypothesis.

Hypoxia downregulates Ku70/80 expression in cervical carcinoma tumors.

Hypoxia may inhibits the NHEJ DNA repair through downregulating Ku70/80 expression and combined with an increased angiogenesis and altered p53 expression would be responsible for tumor progression in cervical carcinoma.

MVP expression is related to IGF1-R in cervical carcinoma patients treated by radiochemotherapy.

OBJECTIVE: To assess the expression of MVP in cervix carcinoma patients treated by radiochemotherapy, its relation to clinical and pathologic prognostic factors and its role in predicting clinical outcome. In addition the relation to IGF-1R expression in this cohort of patients will be explored. MATERIALS AND METHODS: Sixty consecutive patients suffering from localized cervix carcinoma were prospectively included in this study from July 1999 to December 2003. Follow-up was closed in November 2007. Patients were staged following the TNM classification. All patients received pelvic radiation (45-64.80 Gy in 1.8-2 Gy fractions) followed brachytherapy and concomitant cisplatin at 40 mg/m(2)/week doses. MVP expression was studied by immunohistochemistry in paraffin-embedded tumour tissue. RESULTS: MVP was expressed in 58 patients (96.7%) and no relation was found with clinicopathological variables. High MVP expression was related to high IGF1-R expression (p=0.023). Complete response after treatment was observed in 50 patients (83.3%). Clinical stage of the disease and clinical response to radiochemotherapy were the most important prognostic factors related to survival. High MVP and IGF-1R tumour expression was strongly related to poor local and regional disease-free survival (p=0.006), distant disease-free survival (p=0.050), disease-free survival (p=0.006), and cause-specific survival (p=0.007) in patients achieving a complete response. CONCLUSION: MVP and IGF-1R expression were related in clinical cervical tumours and confer reduced long-term local control in patients who achieved clinical complete response to radiochemotherapy.

Radiation-induced DNA damage as a predictor of long-term toxicity in locally advanced breast cancer patients treated with high-dose hyperfractionated radical radiotherapy.

This 14-year-long study makes a novel contribution to the debate on the relationship between the in vitro radiosensitivity of peripheral blood lymphocytes and normal tissue reactions after radiation therapy. The aims were (1) to prospectively assess the degree and time of onset of skin side effects in 40 prospectively recruited consecutive patients with locally advanced breast cancer treated with a hyperfractionated dose-escalation radiotherapy schedule and (2) to assess whether initial radiation-induced DNA damage in peripheral blood lymphocytes of these patients could be used to determine their likelihood of suffering severe late damage to normal tissue. Initial radiation-induced DNA double-strand breaks (DSBs) were assessed in peripheral blood lymphocytes of these patients by pulsed-field electrophoresis. Acute and late cutaneous and subcutaneous toxicity was evaluated using the Radiation Therapy Oncology Group morbidity score. A wide interindividual variation was observed in toxicity grades and in radiation-induced DNA DSBs in peripheral blood lymphocytes (mean 1.61 +/- 0.76 DSBs/Gy per 200 MBp, range 0.63- 4.08), which were not correlated. Multivariate analysis showed a correlation (P < 0.008) between late toxicity and higher prescribed protocol dose (81.6 Gy). Analysis of the 29 patients referred to 81.6 Gy revealed significantly (P < 0.031) more frequent late subcutaneous toxicity in those with intrinsic sensitivity to radiation-induced DNA DSBs of >1.69 DSBs/Gy per DNA unit. Our demonstration of a relationship between the sensitivity of in vitro-irradiated peripheral blood lymphocytes and the risk of developing late toxic effects opens up the possibility of predicting normal tissue response to radiation in individual patients, at least in high-dose non-conventional radiation therapy regimens.

IGF-1R expression in localized cervical carcinoma patients treated by radiochemotherapy.

PURPOSE: To assess the expression of IGF-1R in cervix carcinoma patients treated by radiotherapy and concomitant chemotherapy, its relation to clinical and pathologic prognostic factors and its role in predicting clinical outcome. MATERIALS AND METHODS: Sixty consecutive patients suffering from localized cervix carcinoma were prospectively included in this study from July 1999 to December 2003. Follow-up was closed in March 2006. Patients were staged following the TNM classification. All patients were referred to pelvic radiation up to doses of 45-64.80 Gy in 1.8-2 Gy fractions followed brachytherapy treatment. External radiotherapy boost was used in one patient not receiving brachytherapy (total dose up to 64.80 Gy). All patients received concomitant cisplatin at 40 mg/m(2)/week doses during pelvic radiation. IGF-1R expression was studied by immunohistochemistry in paraffin-embedded tumor tissue. RESULTS: IGF-1R was expressed in 56 patients (93.7%) and no relation was found with clinicopathological variables. Complete response after treatment was observed in 50 patients (83.3%). Clinical stage of the disease and clinical response to radiotherapy were the most important prognostic factors related to survival. Low (negative and fairly) IGF-1R tumor expression was correlated to better long-term Local and Regional Disease Free Survival (p=0.045), Disease-Free Survival (p=0.045), Cause-Specific Survival (p=0.032) and Overall Survival (p=0.021) in patients achieving a complete response. CONCLUSION: High IGF-1R expression is related with reduced long-term local control due to tumor disease radiochemoresistance in patients who initially respond to definitive radiotherapy and concomitant chemotherapy.