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1.
Parasitol Res ; 121(5): 1517-1525, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35238997

RESUMO

Strategies to control goat coccidiosis traditionally rely on the use of management practices combined with anticoccidial treatments, and limited effort has been made, so far, to address immunological control of caprine Eimeria infections. Previously, we showed that monospecific immunization with X-Rad-attenuated Eimeria ninakohlyakimovae oocysts induced considerable immunoprotection upon challenge. In the present study, we conducted a similar vaccination trial but using a mixture of caprine Eimeria species typically present in natural infected goats. For immunization, sporulated oocysts were attenuated by X irradiation (20 kilorad). All infections were performed orally applying 105 sporulated oocysts of mixed Eimeria spp. per animal. In total, 18 goat kids were grouped as follows: (G1) immunized + challenge infected; (G2) primary + challenge infected; (G3) challenge infection control; and (G4) non-immunized/non-infected control. Overall, goat kids infected with attenuated oocysts (= immunized) shed less oocysts in the faeces and showed a lower degree of clinical coccidiosis than animals infected with non-attenuated oocysts. Animals of both challenge groups (G1 and G2) showed partial immunoprotection upon reinfection when compared to challenge infection control (G3). However, the degree of immunoprotection was less pronounced than recently reported for monospecific vaccination against Eimeria ninakohlyakimovae, most probably due to the complexity of the pathogenesis and related immune responses against mixed Eimeria spp. infections. Nevertheless, the data of the present study demonstrate that immunization with attenuated Eimeria spp. oocysts may be worth pursuing as a strategy to control goat coccidiosis.


Assuntos
Coccidiose , Coinfecção , Eimeria , Doenças das Cabras , Animais , Coccidiose/prevenção & controle , Coccidiose/veterinária , Fezes , Doenças das Cabras/prevenção & controle , Cabras , Imunização , Oocistos
2.
Gerontology ; 67(4): 379-385, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33784693

RESUMO

BACKGROUND: Older cancer patients with locally advanced or metastatic disease may benefit from chemotherapy alone or combined with radiotherapy. However, chemotherapy is often omitted either because of physician bias or because of its underlying comorbidity, thus compromising their survival. The coronavirus disease 19 (COVID-19) pandemic is compounding this issue because of the fear of immunosuppression induced by chemotherapy on the elderly which makes them more vulnerable to the virus. SUMMARY: Immunotherapy has less effect on the patient bone marrow compared to chemotherapy. The potential synergy between radiotherapy and immunotherapy may improve local control and survival for older patients with selected cancer. Preliminary data are encouraging because of better survival and local control in diseases which are traditionally resistant to radiotherapy and chemotherapy such as melanoma and renal cell carcinoma. Key Message: We propose a new paradigm combining immunotherapy at a reduced dose and/or extended dosing intervals and hypofractionated radiotherapy for older patients with selected cancer which needs to be tested in future clinical trials.


Assuntos
COVID-19/complicações , Imunoterapia/efeitos adversos , Neoplasias/radioterapia , Idoso , Medula Óssea/imunologia , Medula Óssea/fisiopatologia , Terapia Combinada , Humanos
3.
Rep Pract Oncol Radiother ; 21(5): 435-40, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27489513

RESUMO

BACKGROUND: Graves' ophthalmopathy is the commonest extrathyroidal manifestation of Graves' disease. Treatment options include steroid therapy, corrective/decompressive surgery, radiation therapy or combination of these approaches. AIM: Our purpose was to investigate if retro-orbital irradiation with Volumetric Modulated Arc Therapy (VMAT) yielded better target coverage and dose sparing to adjacent normal structures compared to 3-Dimensional Conformal Radiotherapy (3DCRT) and Lateral Opposing Conformed Fields (LOCF). METHODS: Fourteen consecutive patients diagnosed with bilateral Graves' ophthalmopathy were prospectively recruited into this study from August 2012 until August 2014. An individual VMAT, 3DCRT and LOF plan was created for each patient. Conformity Index (CI), Homogeneity Index (HI) and other dosimetric parameters of the targets and organs-at-risk (OAR) were analyzed in all 28 orbits compared between the different techniques. RESULTS: CI generated by VMAT was superior to that produced by 3DCRT(p < .001) and LOF (p < .001). As expected, 3DCRT was also superior to LOF (p = .007). Regarding the OARs sparing dose (lens, globes, retina and lacrimal glands), VMAT showed a significant benefit when compared with 3DCRT and LOCF, with no differences between the two latter techniques. CONCLUSIONS: VMAT should be preferred over 3DCRT and LOF for bilateral Graves' ophthalmopathy treatment.

4.
Cancers (Basel) ; 16(17)2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39272970

RESUMO

The standard of care for locally advanced non-small-cell lung cancer (NSCLC) is either surgery combined with chemotherapy pre- or postoperatively or concurrent chemotherapy and radiotherapy. However, older and frail patients may not be candidates for surgery and chemotherapy due to the high mortality risk and are frequently referred to radiotherapy alone, which is better tolerated but carries a high risk of disease recurrence. Recently, immunotherapy with immune checkpoint inhibitors (ICIs) may induce a high response rate among cancer patients with positive programmed death ligand 1 (PD-L1) expression. Immunotherapy is also well tolerated among older patients. Laboratory and clinical studies have reported synergy between radiotherapy and ICI. The combination of ICI and radiotherapy may improve local control and survival for NSCLC patients who are not candidates for surgery and chemotherapy or decline these two modalities. The International Geriatric Radiotherapy Group proposes a protocol combining radiotherapy and immunotherapy based on the presence or absence of PD-L1 to optimize the survival of those patients.

5.
Front Oncol ; 14: 1391464, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38854736

RESUMO

The standard of care for non-metastatic renal cancer is surgical resection followed by adjuvant therapy for those at high risk for recurrences. However, for older patients, surgery may not be an option due to the high risk of complications which may result in death. In the past renal cancer was considered to be radio-resistant, and required a higher dose of radiation leading to excessive complications secondary to damage of the normal organs surrounding the cancer. Advances in radiotherapy technique such as stereotactic body radiotherapy (SBRT) has led to the delivery of a tumoricidal dose of radiation with minimal damage to the normal tissue. Excellent local control and survival have been reported for selective patients with small tumors following SBRT. However, for patients with poor prognostic factors such as large tumor size and aggressive histology, there was a higher rate of loco-regional recurrences and distant metastases. Those tumors frequently carry program death ligand 1 (PD-L1) which makes them an ideal target for immunotherapy with check point inhibitors (CPI). Given the synergy between radiotherapy and immunotherapy, we propose an algorithm combining CPI and SBRT for older patients with non-metastatic renal cancer who are not candidates for surgical resection or decline nephrectomy.

6.
Gynecol Oncol ; 122(3): 585-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21708403

RESUMO

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.


Assuntos
Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Receptor IGF Tipo 1/biossíntese , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/terapia , Partículas de Ribonucleoproteínas em Forma de Abóbada/biossíntese , Adulto , Idoso , Antígenos Nucleares/biossíntese , Proteínas de Ligação a DNA/biossíntese , Feminino , Humanos , Imuno-Histoquímica , Antígeno Ki-67/biossíntese , Autoantígeno Ku , Pessoa de Meia-Idade , Resultado do Tratamento , Proteína Supressora de Tumor p53/biossíntese , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/radioterapia
7.
Cancers (Basel) ; 12(5)2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32438703

RESUMO

The coronavirus disease 19 (COVID-19) pandemic is unprecedented as it reached all countries in the world within a record short period of time. Even though COVID-19 infection may be just severe in any adults, older adults (65-year-old or older) may experience a higher mortality rate. Among those affected, cancer patients may have a worse outcome compared to the general population because of their depressed immune status. As the health resources of most countries are limited, clinicians may face painful decisions about which patients to save if they require artificial ventilation. Cancer patients, especially the older ones, may be denied supportive care because of their shorter life expectancy. Thus, special considerations should be taken to prevent infection of older cancer patients and to provide them with adequate social support during their cancer treatment. The following proposal was reached: (1) Education of health care providers about the special needs of older cancer patients and their risks of infection. (2) Special consideration such as surgical masks and separate scheduling should be made to protect them from being infected. (3) Social services such as patient navigators should be provided to ensure adequate medical supply, food, and daily transportation to cancer centers. (4) Close monitoring through phone calls, telecommunication to ensure social distancing and psychological support from patient family to prevent anxiety and depression. (5) Shorter course of radiotherapy by use of hypofractionation where possible to decrease the needs for daily transportation and exposure to infection. (6) Enrollment of older cancer patients in clinical trials for potential antiviral medications if infection does occur. (7) Home health care telemedicine may be an effective strategy for older cancer patients with COVID-19 infection to avoid hospital admission when health care resources become restricted. (8) For selected patients, immunotherapy and targeted therapy may become the systemic therapy of choice for older cancer patients and need to be tested in clinical trials.

8.
Cancers (Basel) ; 11(3)2019 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-30884827

RESUMO

The management of older cancer patients remains difficult because of data paucity. Radiation oncologists need to identify potential issues which could affect treatment of those patients. A workshop was organized in Barcelona among international radiation oncologists with special interest in the management of older cancer patients on April 22, 2018. The following consensus was reached: 1. Older cancer patients often faced unconscious discriminating bias from cancer specialists and institutions because of their chronological age. 2. Advances in radiotherapy techniques have allowed patients with multiple co-morbidities precluding surgery or systemic therapy to achieve potential cure in early disease stages. 3. The lack of biomarkers for frailty remains an impediment to future research. 4. Access to healthcare insurance and daily transportation remains an issue in many countries; 5. Hypofractionation, brachytherapy, or stereotactic techniques may be ideally suited for older cancer patients to minimize transportation issues and to improve tolerance to radiotherapy. 6. Patients with locally advanced disease who are mentally and physically fit should receive combined therapy for potential cure. 7. The role of systemic therapy alone or combined with radiotherapy for frail patients needs to be defined in future clinical trials because of targeted agents or immunotherapy may be less toxic compared to conventional chemotherapy.

9.
Radiother Oncol ; 89(2): 222-6, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18706726

RESUMO

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.


Assuntos
Antígenos Nucleares/genética , Proteínas de Ligação a DNA/genética , Hipóxia/genética , Neoplasias do Colo do Útero/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Regulação para Baixo , Feminino , Humanos , Técnicas Imunoenzimáticas , Autoantígeno Ku , Pessoa de Meia-Idade , Estudos Prospectivos , Neoplasias do Colo do Útero/radioterapia
10.
Gynecol Oncol ; 110(3): 304-7, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18599112

RESUMO

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.


Assuntos
Receptor IGF Tipo 1/biossíntese , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/terapia , Partículas de Ribonucleoproteínas em Forma de Abóbada/biossíntese , Estudos de Coortes , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/radioterapia
11.
Radiat Res ; 168(4): 415-22, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17903032

RESUMO

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.


Assuntos
Neoplasias da Mama/radioterapia , Dano ao DNA , Fracionamento da Dose de Radiação , Adulto , Idoso , Quebras de DNA de Cadeia Dupla , Feminino , Humanos , Pessoa de Meia-Idade , Tolerância a Radiação , Radioterapia/efeitos adversos , Pele/efeitos da radiação
12.
Cancer Lett ; 356(1): 5-16, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24045041

RESUMO

In planning treatment for each new patient, radiation oncologists pay attention to the aspects that they control. Thus their attention is usually focused on volume and dose. The dilemma for the physician is how to protract the treatment in a way that maximizes control of the tumor and minimizes normal tissue injury. The initial radiation-induced damage to DNA may be a biological indicator of the quantity of energy transferred to the DNA. However, until now the biophysical models proposed cannot explain either the early or the late adverse effects of radiation, and a more general theory appears to be required. The bystander component of tumor cell death after radiotherapy measured in many experimental works highlights the importance of confirming these observations in a clinical situation.


Assuntos
Efeito Espectador/efeitos da radiação , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Neoplasias/radioterapia , Apoptose/efeitos da radiação , Fenômenos Biofísicos , Instabilidade Cromossômica/efeitos da radiação , Reparo do DNA/genética , Humanos , Modelos Biológicos , Estresse Oxidativo/efeitos da radiação , Tolerância a Radiação
13.
Transl Oncol ; 5(1): 1-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22348170

RESUMO

Insulin-like growth factor 1 receptor (IGF-1R) is a transmembrane receptor tyrosine kinase involved in the development and progression of cancer whose activation strongly promotes cell growth and survival. IGF-1R exerts its main actions through the activation of the mitogen-activated protein kinase and phosphoinositide 3-kinase pathways. In addition to their traditional roles, IGF-1R activation has been associated with increased radioresistance both in vitro and in vivo, although the molecular mechanisms behind this process are still unclear. Recently, IGF-1R has been associated to new partners as major vault proteins, BCL-2, BAX, or Ku70/80, related to radiochemotherapy resistance, regulation of apoptosis, and nonhomologous end-joining DNA repair. Here, we review these novel associations of IGF-1R trying to explain the resistance to radiotherapy mediated by IGF-1R. Finally, we revised the role of new therapies leading to block the receptor to enhance the efficacy of radiation.

14.
Int J Radiat Biol ; 87(4): 424-31, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21142701

RESUMO

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.


Assuntos
Bioensaio/métodos , Linfócitos/efeitos da radiação , Lesões por Radiação/etiologia , Lesões por Radiação/patologia , Radioterapia Conformacional/efeitos adversos , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/radioterapia , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Feminino , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento , Neoplasias do Colo do Útero/complicações
15.
Int J Radiat Oncol Biol Phys ; 76(1): 9-13, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-20005452

RESUMO

PURPOSE: To elucidate whether microsatellite instability (MSI) predicts clinical outcome in radiation-treated endometrioid endometrial cancer (EEC). METHODS AND MATERIALS: A consecutive series of 93 patients with EEC treated with extrafascial hysterectomy and postoperative radiotherapy was studied. The median clinical follow-up of patients was 138 months, with a maximum of 232 months. Five quasimonomorphic mononucleotide markers (BAT-25, BAT-26, NR21, NR24, and NR27) were used for MSI classification. RESULTS: Twenty-five patients (22%) were classified as MSI. Both in the whole series and in early stages (I and II), univariate analysis showed a significant association between MSI and poorer 10-year local disease-free survival, disease-free survival, and cancer-specific survival. In multivariate analysis, MSI was excluded from the final regression model in the whole series, but in early stages MSI provided additional significant predictive information independent of traditional prognostic and predictive factors (age, stage, grade, and vascular invasion) for disease-free survival (hazard ratio [HR] 3.25, 95% confidence interval [CI] 1.01-10.49; p = 0.048) and cancer-specific survival (HR 4.20, 95% CI 1.23-14.35; p = 0.022) and was marginally significant for local disease-free survival (HR 3.54, 95% CI 0.93-13.46; p = 0.064). CONCLUSIONS: These results suggest that MSI may predict radiotherapy response in early-stage EEC.


Assuntos
Neoplasias do Endométrio/radioterapia , Instabilidade de Microssatélites , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/mortalidade , Neoplasias do Endométrio/patologia , Neoplasias do Endométrio/cirurgia , Métodos Epidemiológicos , Feminino , Marcadores Genéticos , Humanos , Histerectomia/métodos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Resultado do Tratamento
16.
Int J Radiat Oncol Biol Phys ; 73(4): 976-9, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-19251084

RESUMO

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.


Assuntos
Antígenos Nucleares/metabolismo , Apoptose/fisiologia , Reparo do DNA , Proteínas de Ligação a DNA/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias do Colo do Útero , Partículas de Ribonucleoproteínas em Forma de Abóbada/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos Nucleares/genética , Proliferação de Células , Instabilidade Cromossômica/genética , Dano ao DNA/genética , Proteínas de Ligação a DNA/genética , Regulação para Baixo , Feminino , Humanos , Autoantígeno Ku , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Estadiamento de Neoplasias , Estudos Prospectivos , Receptor IGF Tipo 1/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/fisiopatologia , Proteína X Associada a bcl-2/metabolismo
17.
Radiat Oncol ; 4: 17, 2009 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-19497124

RESUMO

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.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/radioterapia , Perfilação da Expressão Gênica , Tolerância a Radiação/genética , Radioterapia/efeitos adversos , Feminino , Humanos , Pessoa de Meia-Idade
18.
Gynecol Oncol ; 106(1): 8-11, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17490736

RESUMO

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.


Assuntos
Receptor IGF Tipo 1/biossíntese , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/terapia , Adulto , Idoso , Terapia Combinada , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/radioterapia
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