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1.
Cancers (Basel) ; 15(8)2023 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37190134

RESUMO

BACKGROUND: Breast cancer treatment has seen tremendous progress since the early 1980s, with the first findings of new chemotherapy and hormone therapies. Screening started in the same period. METHODS: A review of population data (SEER and the literature) shows an increase in recurrence-free survival until 2000 and it stagnates afterwards. RESULTS: Over the period 1980-2000, the 15% survival gain was presented by pharma as a contribution of new molecules. The contribution of screening during that same period was not implemented by them, although screening has been accepted as a routine procedure in the States since the 1980s and everywhere else since 2000. CONCLUSIONS: Interpretation of breast cancer outcome has largely focused on drugs, whereas other factors, such as screening, prevention, biologics, and genetics, were largely neglected. More attention should now be paid to examining the strategy based on realistic global data.

2.
Cancers (Basel) ; 15(18)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37760641

RESUMO

There was a cited reference error in the original article [...].

3.
Int J Radiat Oncol Biol Phys ; 70(3): 728-34, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17904302

RESUMO

PURPOSE: To explore the efficacy and toxicity profile of helical tomotherapy in the preoperative treatment of patients with rectal cancer. PATIENTS AND METHODS: Twenty-four patients with T3/T4 rectal cancer were included in this nonrandomized noncontrolled study. A dose of 46 Gy in daily fractions of 2 Gy was delivered to the presacral space and perineum if an abdominoperineal resection was deemed necessary. This dose was increased by a simultaneous integrated boost to 55.2 Gy when the circumferential resection margin was less than 2 mm on magnetic resonance imaging. Acute toxicity was evaluated weekly. Metabolic response was determined in the fifth week after the end of radiotherapy by means of fluorodeoxyglucose-positron emission tomography scan. A metabolic response was defined as a decrease in maximal standardized uptake value of more than 36%. RESULTS: The mean volume of small bowel receiving more than 15 Gy and mean bladder dose were 227 ml and 20.8 Gy in the no-boost group and 141 ml and 21.5 Gy in the boost group. Only 1 patient developed Grade 3 enteritis. No other Grade 3 or 4 toxicities were observed. Two patients developed an anastomotic leak within 30 days after surgery. The metabolic response rate was 45% in the no-boost group compared with 77% in the boost group. All except 1 patient underwent an R0 resection. CONCLUSIONS: Helical tomotherapy may decrease gastrointestinal toxicity in the preoperative radiotherapy of patients with rectal cancer. A simultaneous integrated radiation boost seems to result in a high metabolic response rate without excessive toxicity.


Assuntos
Radioterapia de Intensidade Modulada/métodos , Neoplasias Retais/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fluordesoxiglucose F18/farmacocinética , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia , Compostos Radiofarmacêuticos/farmacocinética , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/efeitos adversos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/cirurgia , Tomografia Computadorizada Espiral/métodos
4.
Int J Radiat Oncol Biol Phys ; 71(3): 647-51, 2008 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-18514774

RESUMO

Activated T lymphocytes are known to kill tumor cells by triggering cytolytic mechanisms; however, their ability to enhance radiation responses remains unclear. This study examined the radiosensitizing potential of mouse CD8+ T cells, obtained by T-cell-tailored expansion and immunomagnetic purification. Activated CD8+ T cells displayed an interferon (IFN)-gamma+ phenotype and enhanced by 1.8-fold the radiosensitivity of EMT-6 tumor cells in 1% oxygen, which modeled tumor-relevant hypoxia. Radiosensitization was counteracted by neutralizing IFN-gamma or by blocking the inducible isoform of nitric oxide synthase, thus delineating the immune-tumor cell interaction through the IFN-gamma secretion pathway. Reverse transcriptase-polymerase chain reaction, enzyme-linked immunosorbent assay, and fluorescence-activated cell sorter data in agreement detected downregulation of the IFN-gamma gene by hypoxia, which caused IFN-gamma deficiency next to radioresistance. Therefore, immune and radiation responses are likely to be allied in the hypoxic tumor microenvironment, and CD8+ T cells may bridge immunostimulatory and radiosensitizing strategies.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos da radiação , Imunidade Inata/imunologia , Interferon gama/imunologia , Neoplasias Mamárias Animais/imunologia , Animais , Hipóxia Celular/imunologia , Hipóxia Celular/efeitos da radiação , Células Cultivadas , Relação Dose-Resposta à Radiação , Imunidade Inata/efeitos da radiação , Camundongos , Camundongos Endogâmicos BALB C , Doses de Radiação
5.
Int J Radiat Oncol Biol Phys ; 66(5): 1473-80, 2006 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-17056198

RESUMO

PURPOSE: To explore whether antitumor immunoadjuvant OM-174 can stimulate immune cells to produce interferon-gamma (IFN-gamma) and thereby radiosensitize tumor cells. METHODS AND MATERIALS: Splenocytes from BALB/c mice were stimulated by OM-174 at plasma-achievable concentrations (0.03-3 mug/mL), and afterward analyzed for the expression and secretion of IFN-gamma by reverse transcriptase-polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. Stimulated splenocytes were used as a source of IFN-gamma to radiosensitize hypoxic EMT-6 tumor cells through the cytokine-inducible isoform of nitric oxide synthase (iNOS). RESULTS: OM-174 activated the production of IFN-gamma at high levels that reached 70 ng/mL in normoxia (21% oxygen) and 27 ng/mL in tumor-relevant hypoxia (1% oxygen). This caused up to 2.1-fold radiosensitization of EMT-6 tumor cells, which was associated with the iNOS-mediated production of the radiosensitizing molecule nitric oxide, as confirmed by accumulation of its oxidative metabolite nitrite, Western blot analysis, and reverse transcriptase-polymerase chain reaction. Both iNOS activation and radiosensitization were counteracted by neutralizing antibodies against IFN-gamma. The same mechanism of radiosensitization through the IFN-gamma secretion pathway was identified for IL-12 + IL-18, which are known to mediate IFN-gamma responses. Hypoxia displayed a dual effect on the immune-tumor cell interaction, by downregulating the expression of the IFN-gamma gene while upregulating iNOS at transcriptional level. CONCLUSION: Immunoadjuvant OM-174 is an efficient radiosensitizer of tumor cells through activation of the IFN-gamma secretion pathway in immune cells. This finding indicates a rationale for combining immunostimulatory and radiosensitizing strategies and extends the potential therapeutic applications of OM-174.


Assuntos
Adjuvantes Imunológicos/farmacologia , Interferon gama/metabolismo , Lipopolissacarídeos/farmacologia , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/biossíntese , Tolerância a Radiação , Animais , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Regulação para Baixo , Ativação Enzimática , Imunidade Celular , Interferon gama/antagonistas & inibidores , Interferon gama/genética , Interleucina-12/metabolismo , Interleucina-18/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/genética , RNA Mensageiro/metabolismo , Tolerância a Radiação/efeitos dos fármacos , Tolerância a Radiação/imunologia , Baço/citologia , Regulação para Cima
6.
Haematologica ; 90(6): 810-7, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15951294

RESUMO

BACKGROUND AND OBJECTIVES: Unlike most other tumors, multiple myeloma (MM) cells have to survive and to grow in a bone marrow (BM) microenvironment which is already hypoxic by nature. BM hypoxia is crucial for normal hematopoiesis. However, how BM hypoxia and MM affect each other is unknown. We addressed this topic in the 5T2MM mouse model. DESIGN AND METHODS: Levels of hypoxia in the BM of control and tumor-bearing mice were analyzed by flow cytometric analysis of pimonidazole hypoxyprobe binding and hypoxia-inducible factor 1alpha (HIF-1alpha) expression. Micro-vessel density was measured by CD31 staining of BM sections for immunohistochemistry. Apoptosis sensitivity of CD45 5T2MM subsets in hypoxic conditions were analyzed by detection of active caspase-3. RESULTS: Analysis of control and 5T2MM diseased mice injected with pimonidazole hypoxyprobe indicated that both normal BM and myeloma-infiltrated BM are hypoxic. However, the hypoxia in the myelomatous BM was significantly decreased. Analysis of HIF-1alpha expression, a surrogate marker of hypoxia, also demonstrated significantly lower levels of hypoxia in myeloma-infiltrated BM. HIF-1alpha expression was inversely correlated with the micro-vessel density. In vitro culture of 5T2MM cells under hypoxic conditions indicated induction of apoptosis in the CD45- MM-fraction, but not in the CD45+ 5T2MM-cells. INTERPRETATION AND CONCLUSIONS: These data suggest that native BM hypoxia is advantageous for the tumor-initiating CD45+ 5T2MM-cells. Together with the decreased hypoxia in myeloma-infiltrated BM it also indicates that myeloma-associated angiogenesis is functional and permissive for the expansion of CD45- 5T2MM-cells. All together the data raise the possibility of an important role of BM hypoxia in myeloma tumor progression.


Assuntos
Hipóxia , Mieloma Múltiplo/patologia , Animais , Apoptose , Células da Medula Óssea/metabolismo , Caspase 3 , Caspases/metabolismo , Hipóxia Celular , Progressão da Doença , Citometria de Fluxo , Hematopoese , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Antígenos Comuns de Leucócito/biossíntese , Camundongos , Mieloma Múltiplo/metabolismo , Neovascularização Patológica , Nitroimidazóis/farmacologia
7.
Int J Radiat Oncol Biol Phys ; 60(2): 598-606, 2004 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-15380597

RESUMO

PURPOSE: This study examines whether activated macrophages may radiosensitize tumor cells through the release of proinflammatory mediators. METHODS AND MATERIALS: RAW 264.7 macrophages were activated by lipid A, and the conditioned medium (CM) was analyzed for the secretion of cytokines and the production of nitric oxide (NO) through inducible nitric oxide synthase (iNOS). EMT-6 tumor cells were exposed to CM and analyzed for hypoxic cell radiosensitivity. The role of nuclear factor (NF)-kappaB in the transcriptional activation of iNOS was examined by luciferase reporter gene assay. RESULTS: Clinical immunomodulator lipid A, at a plasma-relevant concentration of 3 microg/mL, stimulated RAW 264.7 macrophages to release NO, tumor necrosis factor (TNF)-alpha, and other cytokines. This in turn activated iNOS-mediated NO production in EMT-6 tumor cells and drastically enhanced their radiosensitivity. Radiosensitization was abrogated by the iNOS inhibitor aminoguanidine but not by a neutralizing anti-TNF-alpha antibody. The mechanism of iNOS induction was linked to NF-kappaB but not to JAK/STAT signaling. Interferon-gamma further increased the NO production by macrophages to a level that caused radiosensitization of EMT-6 cells through the bystanding effect of diffused NO. CONCLUSIONS: We demonstrate for the first time that activated macrophages may radiosensitize tumor cells through the induction of NO synthesis, which occurs in both tumor and immune cells.


Assuntos
Lipídeo A/farmacologia , Macrófagos/efeitos dos fármacos , Neoplasias Mamárias Animais/radioterapia , Óxido Nítrico/biossíntese , Tolerância a Radiação , Animais , Hipóxia Celular , Linhagem Celular Tumoral , Meios de Cultivo Condicionados/química , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Feminino , Guanidinas/farmacologia , Interferon gama/farmacologia , Interleucinas/análise , Ativação de Macrófagos , Macrófagos/imunologia , Macrófagos/metabolismo , Neoplasias Mamárias Animais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Nitritos/análise , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/biossíntese
8.
Int J Radiat Oncol Biol Phys ; 57(3): 779-86, 2003 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-14529784

RESUMO

PURPOSE: Lipid A has shown promising immunostimulatory effects in both experimental tumor models and advanced stage cancer patients. This study examines whether lipid A may directly modulate the radioresponse of tumor cells by activating inducible nitric oxide synthase (iNOS) or cyclooxygenase-2 (COX-2) through nuclear factor-kappaB (NF-kappaB) signaling. METHODS AND MATERIALS: Hypoxic EMT-6 tumor cells were exposed to lipid A and analyzed for the level of COX-2 and iNOS by Western blotting and enzymatic assays. The hypoxic radioresponse of EMT-6 cells was estimated by clonogenic survival. The activation of NF-kappaB was examined by immunostaining of its p65 subunit and by luciferase reporter gene assay. RESULTS: Lipid A dose-dependently increased the expression and activity of iNOS with a maximal effect at plasma achievable concentrations of 3-30 micro g/mL. The COX-2 mediated production of prostaglandin E2 was constitutively high and further upregulated by lipid A. The radiosensitivity of hypoxic EMT-6 cells was increased up to 2.5 times and counteracted by the iNOS inhibitor aminoguanidine but not by the COX-2 inhibitor NS-398. The mechanism of radiosensitization was linked to NF-kappaB signaling, because its inhibition by phenylarsine oxide impaired both iNOS activation and radioresponse. CONCLUSION: Lipid A is an efficient hypoxic cell radiosensitizer at plasma relevant concentrations, which provides a rationale to combine lipid A with radiotherapy in further studies.


Assuntos
Isoenzimas/metabolismo , Lipídeo A/farmacologia , NF-kappa B/fisiologia , Óxido Nítrico Sintase/metabolismo , Prostaglandina-Endoperóxido Sintases/metabolismo , Radiossensibilizantes/farmacologia , Transdução de Sinais/fisiologia , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos da radiação , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase/farmacologia , Relação Dose-Resposta a Droga , Ativação Enzimática , Inibidores Enzimáticos/farmacologia , Guanidinas , Humanos , Proteínas de Membrana , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II , Nitrobenzenos/farmacologia , Sulfonamidas/farmacologia
9.
Int J Radiat Oncol Biol Phys ; 76(5): 1520-7, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20338478

RESUMO

PURPOSE: Nitric oxide (NO), synthesized by the inducible nitric oxide synthase (iNOS), is known to inhibit metabolic oxygen consumption because of interference with mitochondrial respiratory activity. This study examined whether activation of iNOS (a) directly in tumor cells or (b) in bystander macrophages may improve radioresponse through sparing of oxygen. METHODS AND MATERIALS: EMT-6 tumor cells and RAW 264.7 macrophages were exposed to bacterial lipopolysaccharide plus interferon-gamma, and examined for iNOS expression by reverse transcription polymerase chain reaction, Western blotting and enzymatic activity. Tumor cells alone, or combined with macrophages were subjected to metabolic hypoxia and analyzed for radiosensitivity by clonogenic assay, and for oxygen consumption by electron paramagnetic resonance and a Clark-type electrode. RESULTS: Both tumor cells and macrophages displayed a coherent picture of iNOS induction at transcriptional/translational levels and NO/nitrite production, whereas macrophages showed also co-induction of the inducible heme oxygenase-1, which is associated with carbon monoxide (CO) and bilirubin production. Activation of iNOS in tumor cells resulted in a profound oxygen sparing and a 2.3-fold radiosensitization. Bystander NO-producing, but not CO-producing, macrophages were able to block oxygen consumption by 1.9-fold and to radiosensitize tumor cells by 2.2-fold. Both effects could be neutralized by aminoguanidine, a metabolic iNOS inhibitor. An improved radioresponse was clearly observed at macrophages to tumor cells ratios ranging between 1:16 to 1:1. CONCLUSIONS: Our study is the first, as far as we are aware, to provide evidence that iNOS may induce radiosensitization through oxygen sparing, and illuminates NO-producing macrophages as a novel determinant of tumor cell radioresponse within the hypoxic tumor microenvironment.


Assuntos
Ativação de Macrófagos , Macrófagos/enzimologia , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/biossíntese , Consumo de Oxigênio/fisiologia , Tolerância a Radiação/fisiologia , Animais , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Respiração Celular , Espectroscopia de Ressonância de Spin Eletrônica , Ativação Enzimática , Guanidinas/farmacologia , Heme Oxigenase-1/biossíntese , Interferon gama/farmacologia , Lipopolissacarídeos/farmacologia , Camundongos , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores
10.
Int J Radiat Oncol Biol Phys ; 74(5): 1476-80, 2009 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-19231097

RESUMO

PURPOSE: Preoperative (chemo)radiotherapy is considered to be standard of care in locally advanced rectal cancer, but is associated with significant small-bowel toxicity. The aim of this study was to explore to what extent helical tomotherapy and daily megavolt (MV) CT imaging may reduce the irradiated volume of small bowel. METHODS AND MATERIALS: A 3D-conformal radiotherapy (3D-CRT) plan with CTV-PTV margins adjusted for laser-skin marks (15, 15, and 10 mm for X, Y, and Z directions, respectively) was compared with helical tomotherapy (IMRT) using the same CTV-PTV margins, and to helical tomotherapy with margins adapted to daily MV-CT imaging (IMRT/IGRT; 8, 11, 7, and 10 mm for X, Y(ant), Y(post) and Z resp.) for 11 consecutive patients. The planning goals were to prescribe 43.7 Gy to 95% of the PTV, while minimizing the volume of small bowel receiving more than 15 Gy (V(15 SB)). RESULTS: The mean PTV was reduced from 1857.4 +/- 256.6 cc to 1462.0 +/- 222.3 cc, when the CTV-PTV margins were adapted from laser-skin marks to daily MV-CT imaging (p < 0.01). The V(15 SB) decreased from 160.7 +/- 102.9 cc to 110.9 +/- 74.0 cc with IMRT and to 81.4 +/- 53.9 cc with IMRT/IGRT (p < 0.01). The normal tissue complication probability (NTCP) for developing Grade 2+ diarrhea was reduced from 39.5% to 26.5% with IMRT and to 18.0% with IMRT/IGRT (p < 0.01). CONCLUSION: The combination of helical tomotherapy and daily MV-CT imaging significantly decreases the irradiated volume of small bowel and its NTCP.


Assuntos
Diarreia/prevenção & controle , Intestino Delgado/efeitos da radiação , Radioterapia de Intensidade Modulada/métodos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/radioterapia , Tomografia Computadorizada por Raios X/métodos , Diarreia/etiologia , Feminino , Humanos , Imageamento Tridimensional , Intestino Delgado/diagnóstico por imagem , Masculino , Lesões por Radiação/complicações , Proteção Radiológica , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/efeitos adversos , Radioterapia Conformacional/métodos , Radioterapia de Intensidade Modulada/efeitos adversos , Neoplasias Retais/patologia , Carga Tumoral
11.
Eur J Intern Med ; 14(6): 377-379, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14769497

RESUMO

The association of an asymptomatic mass, normal thyroid function, and a cold nodule can occur months to years after a primary cancer. Work-up should include ruling out other metastases and fine-needle aspiration cytology. We report six cases of secondary thyroid cancer. Two of the patients in our series presented with hyperthyroidism, which may be due to invasion and disruption of thyroid follicles.

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