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1.
J Dermatolog Treat ; 32(7): 812-818, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31868056

RESUMO

BACKGROUND: Despite being employed in the treatment of inflammatory disorders for more than 20 years all over the world, data regarding photocarcinogenic risks of anti-TNF agents is scarce. OBJECTIVE: To assess photocarcinogenic potential of anti-TNF agents. METHODS: This was a placebo controlled, split-body (UVB-treated versus -untreated) study on mice. Treatment groups were infliximab (n = 11), etanercept (n = 11), cyclosporine (n = 11) and vehicle control (n = 11). Agents were introduced on the 10th week of phototherapy and continued through 24th week. The macroscopic, histological and immunohistochemical analysis of test sites were carried out. RESULTS: Overall 132 tumors were detected on test sites. All of these tumors developed on UV-exposed sides. Histologic examination of these tumors was compatible with keratinocytic neoplasia in 128, mastocytosis in 3, epidermal cyst in 1. Median tumor burden in the UVB exposed areas for ETN, IFX, CYC, and control groups were 14.91, 10.20, 6.28, and 3.14 cm2, respectively. ETN group demonstrated both higher tumor burden and keratinocytic neoplasia numbers than controls (p = .03, p = .025). Although there were 1.8 and 1.7 times more keratinocytic neoplasms in IFX and CYC groups compared to controls, these differences didn't reach statistically significant levels (p = .14; p = .19). CONCLUSION: This study points out to a significant photocarcinogenic potential of anti-TNF agent etanercept.


Assuntos
Etanercepte/efeitos adversos , Neoplasias Induzidas por Radiação/patologia , Neoplasias Cutâneas , Inibidores do Fator de Necrose Tumoral/efeitos adversos , Animais , Infliximab/efeitos adversos , Camundongos , Neoplasias Cutâneas/patologia
2.
Clin Breast Cancer ; 21(1): e96-e101, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32855081

RESUMO

BACKGROUND: The medical literature defining breast cancer recurrence and secondary cancers after autologous tissue reconstruction for breast cancer is sparse. We sought to identify and analyze occurrences at our institution. PATIENTS AND METHODS: A 20-year retrospective review of cancer recurrences and atypical breast neoplasms after autologous tissue breast reconstruction at Roswell Park Comprehensive Cancer Center was conducted after being granted a waiver from the institutional review board. RESULTS: Eighteen locoregional recurrences among 337 cases were identified and analyzed. Overall recurrence rate was 5.3%. Four secondary cancers (1.2%) were radiation-induced angiosarcoma, undifferentiated pleomorphic sarcoma, and metaplastic carcinoma. One case of flat epithelial atypia was identified. CONCLUSION: Our retrospective review found incidence and survival after treatment of breast cancer concordant with reports in the literature. We also identified and analyzed secondary neoplasms, including a unique case of undifferentiated pleomorphic sarcoma and metachronous recurrence of breast carcinoma. A case of recurrence as metaplastic carcinoma was identified.


Assuntos
Neoplasias da Mama/cirurgia , Mamoplastia/efeitos adversos , Recidiva Local de Neoplasia/patologia , Segunda Neoplasia Primária/patologia , Adulto , Idoso , Neoplasias da Mama/patologia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/patologia , Transplante Autólogo
4.
PLoS One ; 15(4): e0232009, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32353018

RESUMO

Non-melanoma skin cancer (NMSC) has a high and increasing incidence all over the world. Solar radiation is the main aetiology for humans. Although most research into photocarcinogenesis uses UVB as a source of radiation, UVA is also carcinogenic in long term. Pomegranate (PGE) and cocoa (CE) extracts have been used for medicinal purposes for time immemorial. Recently, it has been claimed that some of their properties may be an effective preventative measure against photocarcinogenesis and photoaging, but to date in vivo models have not been tested using RUVA, the objective of the present work. A lower incidence of lesions was observed in SKH-1 mice treated with PGE (p<0.001), and lower incidence of invasive squamous carcinoma in both treatment groups (p<0.001 for PGE and p<0.05 for CE); the PGE group also showed a lower level of cell proliferation than the control group (p<0.001). Significantly greater p53 alteration was observed in the control group than the treatment groups (p<0.001 for PGE and p = 0.05 for CE). No significant differences were found in relation to TIMP-1 and MMP-9. Taken together, the results suggest that oral feeding of PGE and CE to SKH-1 mice affords substantial protection against the adverse effects of RUVA, especially PGE.


Assuntos
Quimioprevenção/métodos , Neoplasias Induzidas por Radiação/prevenção & controle , Extratos Vegetais/farmacologia , Animais , Anticarcinógenos/farmacologia , Cacau/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Pelados , Neoplasias Induzidas por Radiação/patologia , Punica granatum/efeitos dos fármacos , Pele/patologia , Neoplasias Cutâneas/patologia , Raios Ultravioleta/efeitos adversos
5.
Health Phys ; 117(2): 187-192, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31225828

RESUMO

A cluster of nine mesothelioma cases was observed among 341 registrants' deaths in the US Transuranium and Uranium Registries. Descriptive analysis showed that mesothelioma cases had the highest average cumulative external radiation dose compared with lung cancer, other cancer, and noncancer deaths. Further analysis indicated that the mesothelioma cluster was very different demographically from lung cancer, other cancer, and noncancer deaths. Therefore, an internally matched case-control approach was applied to evaluate the differences in an average cumulative external radiation dose between mesothelioma deaths and other causes of death. A Monte Carlo t test was used to examine the statistical significance of the differences. The results showed that there were no significant statistical differences in an average cumulative external radiation dose between mesothelioma and lung cancer, other cancers, or noncancers for the internally matched cases and controls.


Assuntos
Neoplasias Pulmonares/etiologia , Mesotelioma/etiologia , Método de Monte Carlo , Neoplasias Induzidas por Radiação/etiologia , Doenças Profissionais/etiologia , Exposição Ocupacional/efeitos adversos , Urânio/intoxicação , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Humanos , Neoplasias Pulmonares/patologia , Masculino , Mesotelioma/patologia , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/patologia , Doenças Profissionais/patologia , Doses de Radiação , Sistema de Registros/estatística & dados numéricos , Urânio/análise
6.
Med Hypotheses ; 124: 26-30, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30798910

RESUMO

Cancer is caused by a combination of factors, genetic, epigenetics and environmental. Among the latter, environmental pollutants absorbed by contact, inhalation, or ingestion are major proven or suspected culprits. Depleted uranium (DU) is one of them directly pertinent to the military and civilians working in militarized areas. It is considered a weak carcinogen but its implication in cancer development in exposed individuals is supported by various data. Since not all subjects exposed to DU develop cancer, it is likely that DU-dependent carcinogenesis requires cofactors, such as genetic predisposition and deficiencies of the chaperoning and immune systems. It is of the essence to adopt every possible protective measure as well as performing careful screening for early diagnosis to protect the military that work in war areas in which weapons with DU are, or have been, used. These topics are discussed here, along with a proposed working hypothesis for investigating the pathophysiology of DU-related carcinogenesis, including the possible role of the chaperoning system.


Assuntos
Carcinogênese , Militares , Chaperonas Moleculares/química , Neoplasias Induzidas por Radiação/patologia , Exposição Ocupacional , Urânio/efeitos adversos , Poluentes Atmosféricos , Conflitos Armados , Carcinógenos , Exposição Ambiental , Poluentes Ambientais , Epigênese Genética , Humanos , Sistema Imunitário , Modelos Teóricos , Medição de Risco , Pele/efeitos dos fármacos
7.
Radiat Prot Dosimetry ; 183(1-2): 237-241, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30668805

RESUMO

Applying the two-stage clonal expansion model to epidemiology of lung cancer among uranium miners, it has been revealed that radon acts as a promoting agent facilitating the clonal expansion of already mutated cells. Clonal expansion rate increases non-linearly by radon concentration showing a plateau above a given exposure rate. The underlying mechanisms remain unclear. Earlier we proposed that progenitor cell hyperplasia may be induced upon chronic radon exposure. The objective of the present study is to test whether the induction of hyperplasia may provide a quantitative explanation for the plateau in clonal expansion rate. For this purpose, computational epithelium models were prepared with different number of basal cells. Cell nucleus hits were computed by an own-developed Monte-Carlo code. Surviving fractions were estimated based on the number of cell nucleus hits. Cell division rate was computed supposing equilibrium between cell death and cell division. It was also supposed that clonal expansion rate is proportional to cell division rate, and therefore the relative increase in cell division rate and clonal expansion rate are the same functions of exposure rate. While the simulation results highly depend on model parameters with high uncertainty, a parameter set has been found resulting in a cell division rate-exposure rate relationship corresponding to the plateau in clonal expansion rate. Due to the high uncertainty of the applied parameters, however, further studies are required to decide whether the induction of hyperplasia is responsible for the non-linear increase in clonal expansion rate or not. Nevertheless, the present study exemplifies how computational modelling can contribute to the integration of observational and experimental radiation protection research.


Assuntos
Poluentes Radioativos do Ar/toxicidade , Neoplasias Pulmonares/etiologia , Mineração , Doenças Profissionais/etiologia , Radônio/toxicidade , Urânio/toxicidade , Carcinogênese/patologia , Morte Celular/efeitos da radiação , Divisão Celular/efeitos da radiação , Humanos , Hiperplasia , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/patologia , Neoplasias Induzidas por Radiação/patologia , Doenças Profissionais/epidemiologia , Doenças Profissionais/patologia , Exposição Ocupacional , Doses de Radiação , Radiometria/métodos
8.
Prog. obstet. ginecol. (Ed. impr.) ; 61(5): 476-480, sept.-oct. 2018. ilus
Artigo em Espanhol | IBECS | ID: ibc-175082

RESUMO

El angiosarcoma radioinducido de mama tras tratamiento quirúrgico conservador y radioterapia complementaria en una paciente con cáncer de mama es una entidad poco frecuente, de difícil diagnóstico y mal pronóstico. Se presenta el caso de una mujer de 71 años, con antecedentes personales de carcinoma ductal infiltrante de mama izquierda, a la que se practicó tumorectomía y linfadenectomía axilar (pT1cpN0M0), y recibió tratamiento adyuvante con radioterapia y hormonoterapia. 77 meses después del tratamiento, la paciente consultó al presentar una lesión cutánea en la mama izquierda. Tras valoración clínica, radiológica e histológica y con el diagnóstico de angiosarcoma de mama, se practicó mastectomía izquierda. Posteriormente no recibió tratamiento complementario


Radiotherapy-induced angiosarcoma of the breast after conservative surgical treatment and complementary radiotherapy in a patient with breast cancer is a rare condition, with both difficult diagnosis and poor prognosis. We present the case of a 71-year-old woman with a personal history of infiltrating ductal carcinoma of the left breast, who underwent tumorectomy and axillary lymphadenectomy (pT1cpN0M0), and received adjuvant treatment with radiotherapy and hormone therapy. 77 months after treatment, the patient consulted with a skin lesion on her left breast. After clinical, radiological and histological assessment and with the diagnosis of angiosarcoma of the breast, a mastectomy of her left breast was performed. The patient did not receive complementary treatment


Assuntos
Humanos , Feminino , Idoso , Hemangiossarcoma/patologia , Neoplasias da Mama/patologia , Neoplasias Induzidas por Radiação/patologia , Mastectomia , Carcinoma Ductal de Mama/radioterapia , Complicações Pós-Operatórias/cirurgia , Fatores de Risco , Radioterapia Adjuvante/efeitos adversos
9.
Acta Dermatovenerol Croat ; 26(1): 53-57, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29782301

RESUMO

Lymphangioma circumscriptum (LC) is a rare, benign condition, predominantly characterized by the malformation of lymphatic skin vessels. Its onset may be congenital or due to secondary causes such as radiotherapy, infections, or surgical procedures. We present the case of a 55-year-old patient with a pathologic history of squamous cell carcinoma of the penis followed by radical penectomy. Due to metastasis to the locoregional lymph nodes, the entire affected area was subsequently treated with radiation therapy, receiving a total dose of 55.8 Gray. Eight years after this treatment, translucent vesicles filled with a clear liquid appeared on the scrotum. Histopathology confirmed the diagnosis of LC and therapy with CO2 laser was applied, resulting in a favorable outcome. LC of the scrotum may present a long-term radiotherapy-induced complication of this site. Our clinical experience showed that the CO2 laser was the therapy of choice as the vesicles entirely disappeared and healed as white scar-like lesions.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Lasers de Gás , Terapia com Luz de Baixa Intensidade/métodos , Linfangioma/etiologia , Neoplasias Induzidas por Radiação/patologia , Neoplasias Cutâneas/radioterapia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Humanos , Linfangioma/patologia , Linfangioma/radioterapia , Masculino , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/radioterapia , Pênis/patologia , Pênis/cirurgia , Prognóstico , Dosagem Radioterapêutica , Radioterapia Adjuvante , Medição de Risco , Escroto/patologia , Escroto/efeitos da radiação , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia , Resultado do Tratamento
11.
Photochem Photobiol ; 93(4): 975-989, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28295364

RESUMO

The incidence of skin cancers, both nonmelanoma and melanoma, is increasing in the United States. The ultraviolet radiation, mainly from sun, is considered the major cause for these neoplasms. While nonmelanoma skin cancers are far more numerous, melanoma remains the most challenging. This is because melanoma can become extremely aggressive and its incidence is increasing worldwide due to lack of effective early detection, as well as disease recurrence, following both surgery and chemotherapy. Therefore, in addition to better treatment options, newer means are required to prevent melanomas from developing. Chemoprevention is a reasonable cost-effective approach to prevent carcinogenesis by inhibiting the processes of tumor initiation, promotion and progression. Melanoma is a progressive disease, which makes it very suitable for chemopreventive interventions, by targeting the processes and molecular pathways involved in the progression of melanoma. This review discusses the roles of various chemopreventive agents such as NSAIDs, statins, vitamins and dietary agents in melanoma and highlights current advancements and our perspective on future of melanoma chemoprevention. Although considerable preclinical data suggest that melanoma may be prevented or delayed by a numerous chemopreventive agents, we realize there are insufficient clinical studies evaluating their efficacy and long-term safety for human use.


Assuntos
Anticarcinógenos/uso terapêutico , Melanoma/prevenção & controle , Neoplasias Induzidas por Radiação/prevenção & controle , Neoplasias Cutâneas/prevenção & controle , Anti-Inflamatórios não Esteroides/uso terapêutico , Suplementos Nutricionais , Progressão da Doença , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Incidência , Melanoma/epidemiologia , Melanoma/patologia , Neoplasias Induzidas por Radiação/epidemiologia , Neoplasias Induzidas por Radiação/patologia , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/patologia , Luz Solar/efeitos adversos , Protetores Solares/administração & dosagem , Raios Ultravioleta/efeitos adversos , Vitaminas/uso terapêutico
12.
Occup Environ Med ; 74(4): 252-258, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27815431

RESUMO

OBJECTIVES: To examine the risk of death from leukaemia in relation to occupational chronic low-level external and internal radiation exposure in a cohort of 58 972 former German uranium miners with mortality follow-up from 1946 to 2013. METHODS: The red bone marrow (RBM) dose from low-linear energy transfer (LET) (mainly external γ-radiation) and high-LET (mainly radon gas) radiation was estimated based on a job-exposure matrix and biokinetic/dosimetric models. Linear excess relative risks (ERR) and 95% CIs were estimated via Poisson regression for chronic lymphatic leukaemia (CLL) and non-CLL. RESULTS: The mean cumulative low-LET and high-LET RBM doses among the 86% radiation-exposed workers were 48 and 9 mGy, respectively. There was a positive non-significant dose-response for mortality from non-CLL (n=120) in relation to low-LET (ERR/Gy=2.18; 95% CI -0.41 to 6.37) and high-LET radiation (ERR/Gy=16.65; 95% -1.13 to 46.75). A statistically significant excess was found for the subgroup chronic myeloid leukaemia (n=31) in relation to low-LET radiation (ERR/Gy=7.20; 95% CI 0.48 to 24.54) and the subgroup myeloid leukaemia (n=99) (ERR/Gy=26.02; 95% CI 2.55 to 68.99) for high-LET radiation. The ERR/Gy tended to be about five to ten times higher for high-LET versus low-LET radiation; however, the CIs largely overlapped. Results indicate no association of death from CLL (n=70) with either type of radiation. CONCLUSIONS: Our findings indicate an increased risk of death for specific subtypes from non-CLL in relation to chronic low-LET and high-LET radiation, but no such relation for CLL.


Assuntos
Leucemia/mortalidade , Neoplasias Induzidas por Radiação/mortalidade , Doenças Profissionais/mortalidade , Exposição Ocupacional/efeitos adversos , Exposição à Radiação/efeitos adversos , Urânio/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Relação Dose-Resposta à Radiação , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Mineração , Neoplasias Induzidas por Radiação/patologia , Doenças Profissionais/patologia , Exposição Ocupacional/análise , Exposição à Radiação/análise , Radiação Ionizante , Análise de Regressão , Fatores de Risco
13.
Int J Radiat Biol ; 93(4): 394-401, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27827272

RESUMO

PURPOSE: To examine the ability of the meadowsweet preparation to inhibit carcinogenesis induced by ionizing radiation in female rats. MATERIALS AND METHODS: The chemical composition of meadowsweet (Filipendula ulmaria) raw material (ethanol and aqueous extracts of meadowsweet flowers) has been studied for the presence of flavonoids, tannins and catechins. Adult female LIO strain rats were subjected to a single whole body γ-irradiation at a dose of 4 Gy in animal experiments. One group of irradiated rats served as control while the other group, starting from the 10th day after irradiation and until the end of the experiment, was given meadowsweet as a decoction of the flowers instead of drinking water. The average daily intake of meadowsweet (dry raw material) was 1 g/kg body weight. Rats were observed for 16 months. RESULTS: The analyzed meadowsweet extracts showed a sufficiently high content of flavonoids and tannins. In irradiated rats after 16 months the overall incidence of tumors was 79.6% (in 82 of 103 rats), the incidence of malignant tumors was 43.7% and the overall tumor multiplicity was 1.48. Most tumors were localized in the mammary gland - 57.3%. In rats that received meadowsweet, the incidence of all malignant tumors and overall multiplicity of tumors were significantly decreased by 1.5 and 1.3 times, respectively. The greatest reduction of many parameters has been identified for breast tumors: the overall incidence was decreased by 1.5 (p = 0.0174) and the overall multiplicity and multiplicity of malignant tumors - by 1.6 (p = 0.0002) and 2.2 (p = 0.0383) times, respectively. CONCLUSIONS: Meadowsweet preparation showed inhibiting activity on radiation carcinogenesis.


Assuntos
Filipendula/química , Neoplasias Induzidas por Radiação/patologia , Neoplasias Induzidas por Radiação/prevenção & controle , Extratos Vegetais/administração & dosagem , Protetores contra Radiação/administração & dosagem , Animais , Carcinogênese/efeitos dos fármacos , Carcinogênese/efeitos da radiação , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Feminino , Flores/química , Neoplasias Induzidas por Radiação/etiologia , Doses de Radiação , Ratos , Taxa de Sobrevida , Resultado do Tratamento , Irradiação Corporal Total/efeitos adversos
14.
Radiat Environ Biophys ; 55(3): 299-315, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27334643

RESUMO

Lung cancer mortality after radon exposure in the Wismut cohort was analyzed using the two-stage clonal expansion (TSCE) model. A total of 2996 lung cancer deaths among the 58,695 male workers were observed during the follow-up period between 1946 and 2003. Adjustment to silica exposure was performed to find a more accurate estimation of the risk of radon exposure. An additional analysis with the descriptive excess relative risk (ERR) model was carried out for comparison. The TSCE model that best describes the data is nonlinear in the clonal expansion with radon exposure and has a saturation level at an exposure rate of [Formula: see text]. The excess relative risk decreases with age and shows an inverse exposure rate effect. In comparison with the ERR model, the TSCE model predicts a considerably larger risk for low exposures rates below [Formula: see text]. Comparison to other mechanistic studies of lung cancer after exposure to alpha particles using the TSCE model reveals an extraordinary consistency in the main features of the exposure response, given the diversity in the characteristics of the cohorts and the exposure across different studies. This suggests that a nonlinear response mechanism in the clonal expansion, with some level of saturation at large exposure rates, may be playing a crucial role in the development of lung cancer after alpha particle irradiation.


Assuntos
Poluentes Radioativos do Ar/toxicidade , Neoplasias Pulmonares/mortalidade , Modelos Biológicos , Neoplasias Induzidas por Radiação/mortalidade , Radônio/toxicidade , Idoso , Idoso de 80 Anos ou mais , Carcinogênese/patologia , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Mineração , Neoplasias Induzidas por Radiação/patologia , Exposição Ocupacional/efeitos adversos , Exposição à Radiação/efeitos adversos , Risco , Urânio
15.
Bull Exp Biol Med ; 160(5): 705-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27021083

RESUMO

Toxicogenomic parameters were studied in the blood of female rats after exposure to ionizing γ-radiation in a dose of 4 Gy and chemoprophylaxis with α-difluoromethylornithine, eleutherococcus or leuzea extracts, which were used in animals with morphological manifestations of tumor growth under conditions of radiation-induced carcinogenesis. Life-time evaluation of toxicogenomic effects was carried out by express method for measurements of blood nucleotid DNA - fluorescent indication. The level of hyperaneu/polyploidy increased in the blood leukocytes of control rats 30 days after radiation exposure. A significant decrease of genotoxicity as a result of drug treatment in comparison with the number and multiplicity of tumors in irradiated animals was found only in the endocrine and reproductive organs of rats treated by eleutherococcus extract.


Assuntos
Quimioprevenção/métodos , Eflornitina/uso terapêutico , Eleutherococcus/metabolismo , Leucócitos/efeitos da radiação , Leuzea/metabolismo , Neoplasias Induzidas por Radiação/tratamento farmacológico , Neoplasias Induzidas por Radiação/mortalidade , Extratos Vegetais/uso terapêutico , Animais , DNA/genética , Feminino , Raios gama/efeitos adversos , Leucócitos/citologia , Neoplasias Induzidas por Radiação/patologia , Poliploidia , Radiação Ionizante , Ratos , Ratos Wistar
17.
Adv Exp Med Biol ; 810: 390-405, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25207378

RESUMO

Solar radiation represents an essential requirement for life, not only by spending the thermal energy for photosynthesis in plants, which provides our atmosphere with oxygen, but also by facilitating the cutaneous synthesis of vitamin D in vertebrates and many other organisms. It is well known that humans and most vertebrates have to obtain an adequate source of vitamin D, in order to develop and maintain a healthy mineralized skeleton and in order to be protected against cancer and a broad variety of other diseases. On the other hand, solar UV radiation can be assumed to be the most relevant environmental carcinogen causing melanoma and nonmelanoma skin cancer with increasing incidences. During the last decades, epidemiological studies and experimental animal models, including genetically engineered mice, the Xiphophorus hybrid fish, the south american oppossum and human skin xenografts, have further elucidated the multi-step process of UV-induced melanomagenesis. It has to be emphasized that, in contrast to intermittent, short-term high-dose solar UV-exposure, more chronic less intense exposure (which is recommended by many experts in the field to obtain a sufficient vitamin D status) has not been found to be a risk factor for the development of melanoma and in fact has been found in several studies to be protective. Interestingly, several independent lines of investigation have demonstrated convincing evidence that vitamin D and/or analogs may be effective in the prevention and treatment of melanoma. This essay summarizes our present understanding about the pathogenic role of UV radiation and of vitamin D for malignant melanoma.


Assuntos
Melanoma/epidemiologia , Neoplasias Induzidas por Radiação/epidemiologia , Substâncias Protetoras/metabolismo , Neoplasias Cutâneas/epidemiologia , Deficiência de Vitamina D/epidemiologia , Vitamina D/metabolismo , Animais , Relação Dose-Resposta à Radiação , Humanos , Melanoma/complicações , Melanoma/metabolismo , Melanoma/patologia , Neoplasias Induzidas por Radiação/complicações , Neoplasias Induzidas por Radiação/metabolismo , Neoplasias Induzidas por Radiação/patologia , Substâncias Protetoras/farmacologia , Fatores de Risco , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/patologia , Neoplasias Cutâneas/complicações , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Raios Ultravioleta/efeitos adversos , Vitamina D/farmacologia , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/metabolismo , Deficiência de Vitamina D/patologia , Melanoma Maligno Cutâneo
18.
Oncotarget ; 5(11): 3743-55, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25003837

RESUMO

The goal of adjuvant (post-surgery) radiation therapy (RT) for breast cancer (BC) is to eliminate residual cancer cells, leading to better local tumor control and thus improving patient survival. However, radioresistance increases the risk of tumor recurrence and negatively affects survival. Recent evidence shows that breast cancer stem cells (BCSCs) are radiation-resistant and that relatively differentiated BC cells can be reprogrammed into induced BCSCs (iBCSCs) via radiation-induced re-expression of the stemness genes. Here we show that in irradiation (IR)-treated mice bearing syngeneic mammary tumors, IR-induced stemness correlated with increased spontaneous lung metastasis (51.7%). However, IR-induced stemness was blocked by targeting the NF-κB- stemness gene pathway with disulfiram (DSF)and Copper (Cu2+). DSF is an inhibitor of aldehyde dehydrogenase (ALDH) and an FDA-approved drug for treating alcoholism. DSF binds to Cu2+ to form DSF-Cu complexes (DSF/Cu), which act as a potent apoptosis inducer and an effective proteasome inhibitor, which, in turn, inhibits NF-κB activation. Treatment of mice with RT and DSF significantly inhibited mammary primary tumor growth (79.4%) and spontaneous lung metastasis (89.6%) compared to vehicle treated mice. This anti-tumor efficacy was associated with decreased stem cell properties (or stemness) in tumors. We expect that these results will spark clinical investigation of RT and DSF as a novel combinatorial treatment for breast cancer.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Neoplasias Induzidas por Radiação/patologia , Células-Tronco Neoplásicas/efeitos da radiação , Animais , Neoplasias da Mama/cirurgia , Linhagem Celular Tumoral , Feminino , Xenoenxertos , Humanos , Neoplasias Mamárias Experimentais/patologia , Neoplasias Mamárias Experimentais/radioterapia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/patologia , Tolerância a Radiação , Radioterapia Adjuvante , Distribuição Aleatória , Transfecção
19.
J Invest Dermatol ; 134(10): 2610-2619, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24732403

RESUMO

Reactive oxygen species produced in response to UVR are important in skin tumor development. We have previously reported that deficiency of the Ogg1 gene, encoding the repair enzyme for 8-oxo-7,8-dihydroguanine (8-oxoG), increases skin tumor incidence in mice upon repetitive UVB exposure and modulation of UVB-induced inflammatory response. Spirulina platensis is used as a human food supplement because it contains abundant nutritional and antioxidant components. Therefore, we investigated the inhibitory effects of S. platensis on UVB-induced skin tumor development in Ogg1 knockout-(KO) mice and the wild-type (WT) counterpart. Dietary S. platensis suppressed tumor induction and development in both genotypes compared with our previous data without S. platensis. Induction of erythema and ear swelling, one of the hallmarks of UVB-induced inflammatory responses, was suppressed in the skin of Ogg1-KO mice and albino hairless mice fed with dietary S. platensis. Compared with untreated mice, S. platensis-administered mice showed significantly reduced 8-oxoG formation in the skin after UVB exposure. Moreover, we found that S. platensis effectively downregulated the signal proteins p38 mitogen-activated protein kinase, stress-activated protein kinase/c-Jun N-terminal kinase, and extracellular signal-regulated kinase after UVB exposure especially in Ogg1-KO mice. Our results suggest that S. platensis exerts antitumor effects against UVB irradiation in the skin through its anti-inflammatory and antioxidant effects.


Assuntos
Suplementos Nutricionais , Neoplasias Induzidas por Radiação/prevenção & controle , Extratos Vegetais/uso terapêutico , Radiodermite/prevenção & controle , Neoplasias Cutâneas/prevenção & controle , Spirulina , Raios Ultravioleta , Animais , DNA Glicosilases/deficiência , DNA Glicosilases/genética , DNA Glicosilases/metabolismo , Modelos Animais de Doenças , Feminino , Genótipo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos da radiação , Masculino , Camundongos , Camundongos Pelados , Camundongos Knockout , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Neoplasias Induzidas por Radiação/metabolismo , Neoplasias Induzidas por Radiação/patologia , Extratos Vegetais/farmacologia , Radiodermite/metabolismo , Radiodermite/patologia , Pele/metabolismo , Pele/patologia , Pele/efeitos da radiação , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
20.
Exp Cell Res ; 321(2): 240-7, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24384475

RESUMO

Angiosarcomas are rare soft-tissue sarcomas of endothelial cell origin. They can be sporadic or caused by therapeutic radiation, hence secondary breast angiosarcomas are an important subgroup of patients. Assessing the molecular biology of angiosarcomas and identify specific targets for treatment is challenging. There is currently great interest in the role of angiogenesis and of angiogenic factors associated with tumor pathogenesis and as targets for treatment of angiosarcomas. A primary cell line derived from a skin fragment of a irradiation-induced angiosarcoma patient was obtained and utilized to evaluate cell biomarkers CD31, CD34, HIF-1 alpha and VEGFRs expression by immunocytochemistry and immunofluorescence, drugs cytotoxicity by cell counting and VEGF release by ELISA immunoassay. In addition to previous biomarkers, FVIII and VEGF were also evaluated on tumor specimens by immunohistochemistry to further confirm the diagnosis. We targeted the VEGF-VEGFR-2 axis of tumor angiogenesis with two different class of vascular targeted drugs; caprelsa, the VEGFR-2/EGFR/RET inhibitor and bevacizumab the anti-VEGF monoclonal antibody. We found the same biomarkers expression either in tumor specimens and in the cell line derived from tumor. In vitro experiments demonstrated that angiogenesis plays a pivotal role in the progression of this tumor as cells displayed high level of VEGFR-2, HIF-1 alpha strongly accumulated into the nucleus and the pro-angiogenic factor VEGF was released by cells in culture medium. The evaluation of caprelsa and bevacizumab cytotoxicity demonstrated that both drugs were effective in inhibiting tumor proliferation. Due to these results, we started to treat the patient with pazopanib, which was the unique tyrosine kinase inhibitor available in Italy through a compassionate supply program, obtaining a long lasting partial response. Our data suggest that the study of the primary cell line could help physicians in choosing a therapeutic approach for patient that almost in vitro shows chances of success and that the anti-angiogenetic agents are a reliable therapeutic opportunity for angiosarcomas patients.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Hemangiossarcoma/tratamento farmacológico , Neoplasias Induzidas por Radiação/tratamento farmacológico , Idoso , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Feminino , Hemangiossarcoma/patologia , Humanos , Neoplasias Induzidas por Radiação/patologia , Cultura Primária de Células
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