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1.
Histopathology ; 59(1): 40-54, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21771025

RESUMO

AIMS: To investigate the use of a computer-assisted technology for objective, cell-based quantification of molecular biomarkers in specified cell types in histopathology specimens, with the aim of advancing current visual estimation and pixel-level (rather than cell-based) quantification methods. METHODS AND RESULTS: Tissue specimens were multiplex-immunostained to reveal cell structures, cell type markers, and analytes, and imaged with multispectral microscopy. The image data were processed with novel software that automatically delineates and types each cell in the field, measures morphological features, and quantifies analytes in different subcellular compartments of specified cells.The methodology was validated with the use of cell blocks composed of differentially labelled cultured cells mixed in known proportions, and evaluated on human breast carcinoma specimens for quantifying human epidermal growth factor receptor 2, estrogen receptor, progesterone receptor, Ki67, phospho-extracellular signal-related kinase, and phospho-S6. Automated cell-level analyses closely matched human assessments, but, predictably, differed from pixel-level analyses of the same images. CONCLUSIONS: Our method reveals the type, distribution, morphology and biomarker state of each cell in the field, and allows multiple biomarkers to be quantified over specified cell types, regardless of their abundance. It is ideal for studying specimens from patients in clinical trials of targeted therapeutic agents, for investigating minority stromal cell subpopulations, and for phenotypic characterization to personalize therapy and prognosis.


Assuntos
Biomarcadores/metabolismo , Imuno-Histoquímica/métodos , Automação Laboratorial/métodos , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Membrana Celular/metabolismo , Membrana Celular/patologia , Núcleo Celular/metabolismo , Núcleo Celular/patologia , Citoplasma/metabolismo , Citoplasma/patologia , Diagnóstico por Computador/métodos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Técnicas Histológicas/métodos , Humanos , Processamento de Imagem Assistida por Computador , Queratinas/metabolismo , Antígeno Ki-67/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo
2.
Adv Exp Med Biol ; 701: 53-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21445769

RESUMO

Oxygen dependent quenching of phosphorescence has been used to measure the oxygen pressure in both the vasculature of the microcirculation and the interstitial spaces of resting muscle tissue. Oxygen sensitive molecules were either dissolved in the blood (intravascular space) or micro-injected into the interstitial space and the distributions, histograms, of the oxygen pressure were measured. The mean oxygen pressures are higher in the blood than in the interstitial space but the oxygen pressures in the lowest 10% of the two spaces were not significantly different, indicating there is minimal (< 1 mm Hg) oxygen gradient between the two spaces in the capillary bed.


Assuntos
Líquido Extracelular/metabolismo , Músculo Esquelético/metabolismo , Neoplasias Experimentais/metabolismo , Oxigênio/metabolismo , Descanso/fisiologia , Vigília/fisiologia , Anestesia , Animais , Camundongos , Músculo Esquelético/irrigação sanguínea , Neoplasias Experimentais/irrigação sanguínea
3.
Mol Cancer Res ; 7(3): 300-10, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19276184

RESUMO

Signaling through the Tie2 receptor on endothelial cells has been shown to play an important role in normal and pathologic vascular development. We generated K1735 murine melanoma tumor cells that inducibly express soluble Tie2 receptor (Tie2Ex) to study the effects of inhibiting Tie2 signaling on tumor vasculature. Tie2Ex induction rapidly decreased AKT activation but not extracellular signal-regulated kinase (ERK) activation in tumor endothelial cells as detected by immunostaining. This was accompanied by an increase in endothelial cell TUNEL staining but no change in Ki-67 expression. Together with a decrease in the percentage of perfused vessels, this suggested that tumor vessel regression and impaired vascular function rather than angiogenesis inhibition was responsible for the delay in tumor growth following Tie2Ex treatment. However, Tie2Ex failed to inhibit the growth of larger, more established K1735 tumors. These tumors were additionally treated with sorafenib, a multikinase inhibitor that inhibits tumor endothelial cell ERK activation but not AKT activation. Combining Tie2Ex and sorafenib decreased both endothelial cell AKT and ERK activation, decreased endothelial cell survival and proliferation, and significantly inhibited growth of the more established tumors. These studies indicate that activity of specific signaling pathways and prosurvival effects are brought about by Tie2 activation in tumor endothelial cells, and knowledge of the effects of Tie2 inhibition can lead to development of more effective therapeutic regimens for inhibiting tumor neovascularization.


Assuntos
Melanoma Experimental/irrigação sanguínea , Melanoma Experimental/terapia , Receptor TIE-2/metabolismo , Angiopoietina-1/farmacologia , Animais , Apoptose/fisiologia , Benzenossulfonatos/farmacologia , Doxiciclina/farmacologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/enzimologia , Células Endoteliais/metabolismo , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Técnicas In Vitro , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C3H , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Neovascularização Patológica/terapia , Niacinamida/análogos & derivados , Compostos de Fenilureia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Piridinas/farmacologia , Receptor TIE-2/antagonistas & inibidores , Receptor TIE-2/genética , Proteínas Recombinantes/farmacologia , Transdução de Sinais/efeitos dos fármacos , Sorafenibe , Transfecção
4.
Acad Radiol ; 15(9): 1133-41, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18692754

RESUMO

RATIONALE AND OBJECTIVES: The goal was to determine whether the tumor vascular disrupting actions of low-intensity ultrasound were frequency dependent. MATERIALS AND METHODS: The effect of the frequency (1 MHz at 2.2 W/cm2 or 3 MHz at 2.4 W/cm2) of low-intensity ultrasound as a neovascular disrupting modality was investigated in 15 murine melanomas (K1735(22)) insonated for 3 minutes after the intravenous injection of a microbubble contrast agent (Definity). In contrast-enhanced power Doppler observations of each tumor (before and after treatment), measurements were made of the size of the area of the tumor that was perfused with blood containing the ultrasound contrast agent (percentage area of flow [PAF]), and the volume of contrast agent flowing through the unit volume of the tumor (color-weighted fractional area [CWFA]). During insonation of the tumor, the temperature was measured with a fine wire thermocouple in an additional eight mice. RESULTS: The antivascular action of low-intensity ultrasound was significantly enhanced (PAF by 64%; CWFA by 106%) when the tumor was treated with 3-MHz ultrasound rather than 1 MHz (analysis of variance: PAF, P=.02; CWFA, P=.04). The average rate of tumor temperature increase was 2.6+/-1.3 degrees C/min for 1 MHz and 5.0+/-1.7 degrees C/min for 3 MHz; these increases were significantly different (P=.04). CONCLUSIONS: Insonation of the tumor at a higher frequency amplified the heating of the neoplasm and led to greater disruption of the tumor vasculature; 3-MHz ultrasound was more efficacious than 1 MHz for antivascular cancer therapy.


Assuntos
Melanoma Experimental/terapia , Neovascularização Patológica/terapia , Terapia por Ultrassom/métodos , Animais , Temperatura Corporal , Meios de Contraste , Feminino , Fluorocarbonos , Camundongos , Camundongos Endogâmicos C3H
5.
Adv Exp Med Biol ; 614: 53-62, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18290314

RESUMO

A new Oxyphor (Oxyphor G3) has been used to selectively determine the oxygen pressure in interstitial (pericellular) spaces. Oxyphor G3 is a Pd-tetrabenzoporphyrin, encapsulated inside generation 2 poly-arylglycine (AG) dendrimer, and therefore is a true near infrared oxygen sensor, having a strong absorption band at 636nm and emission near 800nm. The periphery of the dendrimer is modified with oligoethylene glycol residues (Av. MW 350) to make the probe water soluble and biologically inert. Oxyphor G3 was injected along "tracks" in the tissue using a small needle (30gage or less) and remained in the pericellular space, allowing oxygen measurements for several hours with a single injection. The oxygen pressure distributions (histograms) were compared with those for Oxyphor G2 in the intravascular (blood plasma) space. In normal muscle, in the lower oxygen pressure region of the histograms (capillary bed) the oxygen pressure difference was small. At higher oxygen pressures in the histograms there were differences consistent with the presence of high flow vessels with oxygen pressures substantially above those of the surrounding interstitial space. In tumors, the oxygen pressures in the two spaces were similar but with large differences among tumors. In mice, anesthesia with ketamine plus xylazine markedly decreased oxygen pressures in the interstitial and intravascular spaces compared to awake or isoflurane anesthetized mice.


Assuntos
Líquido Extracelular/metabolismo , Músculo Esquelético/metabolismo , Neoplasias Experimentais/metabolismo , Oxigênio/análise , Oxigênio/metabolismo , Animais , Dendrímeros/química , Membro Posterior , Metaloporfirinas/síntese química , Metaloporfirinas/química , Camundongos , Peso Molecular , Músculo Esquelético/irrigação sanguínea , Neoplasias Experimentais/irrigação sanguínea , Oxigênio/sangue , Pressão
6.
Ultrasound Med Biol ; 33(12): 1901-10, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17720299

RESUMO

This study investigated whether a microbubble-containing ultrasound contrast agent had a role in the antivascular action of physiotherapy ultrasound on tumor neovasculature. Ultrasound images (B-mode and contrast-enhanced power Doppler [0.02 mL Definity]) were made of 22 murine melanomas (K1735(22)). The tumor was insonated (I(SATA) = 1.7 W cm(-2), 1 MHz, continuous output) for 3 min and the power Doppler observations of the pre- and postinsonation tumor vascularities were analyzed. Significant reductions (p = 0.005 for analyses of color-weighted fractional area) in vascularity occurred when a contrast-enhanced power Doppler study occurred before insonation. Vascularity was unchanged in tumors without a pretherapy Doppler study. Histologic studies revealed tissue structural changes that correlated with the ultrasound findings. The underlying etiology of the interaction between the physiotherapy ultrasound beam, the microbubble-containing contrast agent and the tumor neovasculature is unknown. It was concluded that contrast agents play an important role in the antivascular effects induced by physiotherapy ultrasound.


Assuntos
Fluorocarbonos/uso terapêutico , Melanoma Experimental/terapia , Neovascularização Patológica/terapia , Terapia por Ultrassom/métodos , Animais , Meios de Contraste/uso terapêutico , Feminino , Melanoma Experimental/irrigação sanguínea , Melanoma Experimental/diagnóstico por imagem , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C3H , Microbolhas , Transplante de Neoplasias , Neovascularização Patológica/diagnóstico por imagem , Neovascularização Patológica/patologia , Ultrassonografia Doppler/métodos
7.
J Appl Physiol (1985) ; 101(6): 1648-56, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16888050

RESUMO

This study compared oxygen pressures (Po(2)), measured by oxygen-dependent quenching of phosphorescence, in the intravascular (blood plasma) space in the muscle with those in the interstitial (pericellular) space. Our hypothesis was that the capillary wall would not significantly impede oxygen diffusion from the blood plasma to the pericellular space. A new near-infrared oxygen sensitive probe, Oxyphor G3, was used to obtain oxygen distributions in the interstitial space. Oxyphor G3 is a Pd-tetrabenzoporphyrin encapsulated inside generation 2 poly-arylglycine (AG) dendrimer. The periphery of the dendrimer is modified with oligoethylene glycol residues (average molecular weight 350) to make the probe water soluble and biologically inert. Oxyphor G3 was injected into thigh muscle using a 30-gauge needle. Histograms of the Po(2) in the interstitial space were measured in awake and anesthetized animals and compared with those for Oxyphor G2 in the intravascular (blood plasma) space. For awake mice, the lowest 10% of Po(2) values for the interstitial and intravascular spaces (believed to represent capillary bed) were not significantly different [23.8 (SD 4.5) and 25 Torr (SD 4.3), respectively], whereas, in isoflurane-anesthetized mice, there was a small but significant (P = 0.01) difference [20.4 (SD 6.3) and 27.9 Torr (SD 3.5), respectively]. The peak values for the histograms for the interstitial space in awake and isoflurane-anesthetized mice were 40.8 (SD 7.5) and 36.9 Torr (SD 8.3), respectively, whereas those for the intravascular space were 52.2 (SD 4.9) and 55.9 Torr (SD 8.4), respectively, showing no significant difference due to isoflurane anesthesia. The histograms for the intravascular space were significantly wider, with more contribution at higher Po(2) values. A different anesthetic, ketamine plus xylazine injected intraperitoneally, caused a marked decrease in the tissue Po(2) values in both spaces, with the time course and extent of the decrease dependent on the time after injection and variable among mice. It was, therefore, not further used.


Assuntos
Líquido Extracelular/metabolismo , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/metabolismo , Oxigênio/metabolismo , Descanso/fisiologia , Vigília/fisiologia , Animais , Camundongos , Oxigênio/sangue , Pressão
8.
Ultrasound Med Biol ; 32(3): 453-61, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16530105

RESUMO

This study evaluates the histopathological changes that follow insonation of a neoplasm with physiotherapy ultrasound. In 27 mice (C3HV/HeN strain), a subcutaneous melanoma (K1735(22)) was insonated with continuous physiotherapy ultrasound (1 MHz; spatial-average-temporal-average = 2.3 W cm(-2)). Analyses of contrast enhanced (0.1 mL Optison) power Doppler observations showed that insonation significantly (p < 0.05) increased the avascular area in the neoplasm. The predominant acute effect of insonating the neoplasm was an apparently irreparable dilation of the tumor capillaries with associated intercellular oedema; other immediate effects were haemorrage and increased intercellular fluid. Liquefactive necrosis of neoplastic cells was a delayed effect. There was a high correlation (R2 = 0.91) between the percent area affected on histologic examination and the percent increase in avascularity of the neoplasm in the Doppler study. In conclusion, physiotherapy ultrasound produced histologic changes in the tumor vasculature that were consistent with observations made by contrast enhanced power Doppler ultrasound.


Assuntos
Melanoma Experimental/irrigação sanguínea , Neovascularização Patológica/terapia , Modalidades de Fisioterapia , Neoplasias Cutâneas/irrigação sanguínea , Terapia por Ultrassom/métodos , Albuminas , Animais , Meios de Contraste , Fluorocarbonos , Melanoma Experimental/diagnóstico por imagem , Melanoma Experimental/terapia , Camundongos , Camundongos Endogâmicos , Microbolhas , Transplante de Neoplasias , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/terapia , Ultrassonografia Doppler , Ultrassonografia de Intervenção
9.
Cancer Res ; 63(23): 8073-8, 2003 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-14678955

RESUMO

Selective cytokine inhibitory drugs (SelCIDs) are a novel class of phosphodiesterase 4 inhibitors discovered during a thalidomide analog discovery program. These analogs were evaluated for their ability to inhibit tumor angiogenesis, vascularity, and growth. Two analogs (CC-7034 and CC-9088) were identified that had enhanced antiangiogenic activity in Matrigel assays compared with parental thalidomide. These analogs also inhibited the growth of established K1735 and RENCA murine tumors. Tumors whose growth was suppressed by SelCID treatment exhibited decreased vessel density together with increased tumor cell hypoxia and death. The decrease in vascularity produced by SelCID treatment is attributed to a selective loss of vessels devoid of pericyte coverage, suggesting that these agents target immature tumor vessels. That tumor cell death was localized to relatively avascular or hypoxic areas, coupled with the fact that none of the analogs was cytotoxic in vitro against the tumor cells, demonstrates that these analogs are novel antivascular agents with potent antitumor activity.


Assuntos
Inibidores da Angiogênese/farmacologia , Citocinas/antagonistas & inibidores , Endotélio Vascular/efeitos dos fármacos , Neoplasias Experimentais/irrigação sanguínea , Neovascularização Patológica/tratamento farmacológico , Talidomida/análogos & derivados , Animais , Divisão Celular/efeitos dos fármacos , Hipóxia Celular/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Talidomida/farmacologia
10.
Cancer Res ; 62(3): 747-55, 2002 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-11830529

RESUMO

We examined the ability of recombinant murine interleukin-12 (rmIL-12) to inhibit the vasculature and growth of mammary carcinomas arising in situ in mouse mammary tumor virus (MMTV)-infected female C3H/HeN mice. Although it is a potent antiangiogenic and antitumor agent in many transplanted murine tumor models, rmIL-12 failed to inhibit the vascularity, reduce the perfusion, or alter the growth of these autochthonous carcinomas. Factors intrinsic to these tumor cells were unlikely to be responsible for therapy failure. This is because primary cells derived from these carcinomas responded to IFN-gamma, and rmIL-12 was effective against transplanted tumors arising from Mm5MT cells, a line established from a MMTV-induced mammary carcinoma in C3H mice. Factors intrinsic to the mice that host the autochthonous mammary carcinomas were also not responsible for failure, because they sponsored rmIL-12 antiangiogenic and antitumor effects against transplanted K1735 murine melanoma tumors. Instead, the autochthonous nature of the mammary carcinomas and their possession of a high percentage of mature, pericyte-covered vessels that are resistant to therapeutic regression may be responsible. This is supported by the observation that transplanted Mm5MT tumors had a lower proportion of pericyte-covered vessels and responded to rmIL-12 therapy. These results point to significant differences between the vasculature of transplanted and autochthonous murine tumors and indicate that their susceptibility to antivascular therapy may differ substantially.


Assuntos
Interleucina-12/farmacologia , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/virologia , Vírus do Tumor Mamário do Camundongo , Neovascularização Patológica/prevenção & controle , Animais , Divisão Celular/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Neoplasias Mamárias Experimentais/irrigação sanguínea , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos C3H , Transplante de Neoplasias , Proteínas Recombinantes/farmacologia
11.
Cancer Res ; 63(4): 742-6, 2003 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-12591718

RESUMO

The Ink4a/Arf locus is frequently methylated in colon carcinoma and other common human cancers, suggesting that the locus may play a broad, as yet poorly defined,role inhibiting tumor progression. We examined the influence of the locus in mice with multiple intestinal neoplasia (Min). Colon tumors in 3-month-old Min mice that were null for the Ink4a/Arf locus (-/-) were moderately larger than in Ink4a/Arf-wild-type (+/+) animals (P = 0.032). More strikingly, one-half of the -/- colon tumors were grossly red in color, whereas most of the +/+ tumors were white (P = 0.0025). This color difference remained statistically significant after normalizing for tumor area (P = 0.016). On histological analysis, -/- colon tumors displayed more RBCs near the tumor surface, twice the number of functional vessels, and features of carcinoma in situ not found in +/+ tumors. Biochemical analyses showed that red tumors had higher hemoglobin and vascular endothelial growth factor (VEGF) content than white tumors. Surprisingly, the small intestinal tumor burden was actually lower in -/- animals, and none of these tumors were red, underscoring the importance of tissue context in the function of the locus. These results provide direct evidence that the Ink4a/Arf locus inhibits colon tumor progression. The enhanced vascularity of the -/- tumors is particularly significant in light of the clinical importance of this property in the detection, recurrence, and therapy of colon tumors.


Assuntos
Neoplasias do Colo/irrigação sanguínea , Neoplasias do Colo/genética , Genes p16/fisiologia , Neovascularização Patológica/genética , Proteína Supressora de Tumor p14ARF/genética , Animais , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/fisiologia , Progressão da Doença , Fatores de Crescimento Endotelial/metabolismo , Feminino , Hemoglobinas/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Linfocinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neovascularização Patológica/patologia , Proteína Supressora de Tumor p14ARF/fisiologia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
12.
Cancer Res ; 64(24): 8994-9001, 2004 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-15604264

RESUMO

Progression of tumors to invasive and metastatic forms requires that tumor cells undergo dramatic morphologic changes, a process regulated by Rho GTPases. Elevated expression of RhoA and RhoC, as well as the Rho effector proteins ROCK I and ROCK II, are commonly observed in human cancers and are often associated with more invasive and metastatic phenotypes. To examine how ROCK contributes to the progression of solid tumors, we established a conditionally activated form of ROCK II by fusing the kinase domain to the estrogen receptor hormone-binding domain (ROCK:ER). ROCK:ER-expressing colon carcinoma cells grown as tumors in immunocompromised nude mice organized into discrete clusters surrounding blood vessels. However, ROCK:ER activation resulted in the aggressive dissemination of tumor cells into the surrounding stroma, indicating that increased ROCK signaling is sufficient to promote invasion from solid tumors. In addition, tumors in which ROCK:ER was activated were more highly vascularized, indicating that ROCK contributes to tumor angiogenesis. ROCK:ER activation resulted in changes to epithelial morphology and organization that facilitated motility in vitro, likely by inducing the redistribution of proteins such as ezrin, as well as adherens junction and extracellular matrix-binding proteins. These results suggest that ROCK inhibitors would be useful antimetastatic and antiangiogenic chemotherapeutic agents in tumors associated with elevated RhoA, RhoC, ROCK I, or ROCK II expression.


Assuntos
Neoplasias do Colo/irrigação sanguínea , Neoplasias do Colo/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Tamoxifeno/análogos & derivados , Animais , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Citoesqueleto/enzimologia , Citoesqueleto/patologia , Ativação Enzimática , Células HCT116 , Humanos , Receptores de Hialuronatos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Camundongos , Camundongos Nus , Invasividade Neoplásica , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Proteínas Serina-Treonina Quinases/genética , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Tamoxifeno/farmacologia , Quinases Associadas a rho
13.
Cancer Biol Ther ; 4(12): 1395-1400, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16676437

RESUMO

The vascular effects of ionizing radiation were examined in K1735 murine melanoma tumors. Single-fraction and fractionated radiation virtually arrested growth of these tumors for about a week, after which they resumed more rapid growth. Tumor microvessel density (MVD) and blood perfusion was unchanged seven days after radiation but decreased at later time points after irradiation, when they had grown 10-fold or more. Together with the finding of severe tumor hypoxia and VEGF induction in the latter tumors, the evidence pointed to vascular insufficiency and inhibited neovascularization in tumors that had grown substantially after radiation. Endothelial cell (EC) death detected by TUNEL staining only transiently increased the day following radiation, whereas EC proliferation detected by Ki-67 staining was increased in irradiated tumors that had grown substantially. The fact that increased EC proliferative activity produced fewer vessels suggests that angiogenesis is defective or ineffective after radiation. These results complement recent genetic evidence that EC damage from radiation plays a major role in tissue damage and antitumor efficacy to highlight the importance of EC and vasculature in radiation response. Our studies further show that radiation impact on tumor vasculature extends beyond near-term induction of EC death to more prolonged effects on their ability to support angiogenesis.


Assuntos
Melanoma Experimental/irrigação sanguínea , Melanoma Experimental/radioterapia , Neovascularização Patológica/radioterapia , Radiação Ionizante , Animais , Hipóxia Celular/efeitos da radiação , Citoproteção/efeitos da radiação , Fracionamento da Dose de Radiação , Melanoma Experimental/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Microcirculação/efeitos da radiação , Transplante de Neoplasias , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/metabolismo
14.
J Appl Physiol (1985) ; 98(4): 1503-10, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15579567

RESUMO

In the present work, a novel method for detecting hypoxia in tumors, phosphorescence quenching, was used to evaluate tissue and tumor oxygenation. This technique is based on the concept that phosphorescence lifetime and intensity are inversely proportional to the oxygen concentration in the tissue sample. We used the phosphor Oxyphor G2 to evaluate the oxygen profiles in three murine tumor models: K1735 malignant melanoma, RENCA renal cell carcinoma, and Lewis lung carcinoma. Oxygen measurements were obtained both as histograms of oxygen distribution within the sample and as an average oxygen pressure within the tissue sampled; the latter allowing real-time oxygen monitoring. Each of the tumor types examined had a characteristic and consistent oxygen profile. K1735 tumors were all well oxygenated, with a peak oxygen pressure of 37.8 +/- 5.1 Torr; RENCA tumors had intermediate oxygen pressures, with a peak oxygen pressure of 24.8 +/- 17.9 Torr; and LLC tumors were all severely hypoxic, with a peak oxygen pressure of 1.8 +/- 1.1 Torr. These results correlated well with measurements of tumor cell oxygenation measured by nitroimidazole (EF5) binding and were consistent with assessments of tumor blood flow by contrast enhanced ultrasound and tumor histology. The results show that phosphorescence quenching is a reliable, reproducible, and noninvasive method capable of providing real-time determination of oxygen concentrations within tumors.


Assuntos
Medições Luminescentes/métodos , Metaloporfirinas , Neoplasias Experimentais/metabolismo , Oxigênio/metabolismo , Animais , Hipóxia Celular , Substâncias Luminescentes , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Distribuição Tecidual
15.
Ultrasound Med Biol ; 31(10): 1403-10, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16223644

RESUMO

This study was aimed at determining if physiotherapy ultrasound (US) affected the fragile and leaky angiogenic blood vessels in a tumor. In 22 C3HV/HeN mice, a subcutaneous melanoma (K1735(22)) was insonated (1, 2 or 3 min) with continuous 1-MHz low-intensity (spatial-average temporal-average = 2.28 W cm(-2)), physiotherapy US. Contrast-enhanced (0.1 mL Optison) power Doppler US observations were made and histogram analyses of the images were performed. Before insonation, all but 7% of the tumor was perfused. The avascular area in tumors receiving 3-min treatment increased to 82% (p < 0.001). A linear regression analysis showed that each min of insonation led to a 25% reduction in tumor vascularity; the antivascular activity persisted for 24 h. Histology demonstrated disruption of vascular walls and tumor cell death in areas of vascular congestion and thrombosis. Physiotherapy US particularly targeted the vascular structures, and the effects on tumor cells appeared to be secondary to the resultant ischemia.


Assuntos
Processamento de Imagem Assistida por Computador , Melanoma Experimental/irrigação sanguínea , Neovascularização Patológica/terapia , Neoplasias Cutâneas/irrigação sanguínea , Terapia por Ultrassom/métodos , Albuminas , Animais , Meios de Contraste , Feminino , Fluorocarbonos , Temperatura Alta , Melanoma Experimental/diagnóstico por imagem , Melanoma Experimental/terapia , Camundongos , Camundongos Endogâmicos C3H , Neovascularização Patológica/diagnóstico por imagem , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/terapia , Fatores de Tempo , Terapia por Ultrassom/efeitos adversos , Ultrassonografia Doppler em Cores
16.
Ultrasound Med Biol ; 29(7): 977-84, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12878243

RESUMO

This study evaluated an image-gating method using contrast-enhanced power Doppler ultrasound (US) to estimate blood perfusion in mice tumors. A mathematical model that compensates for the effect of bubble destruction by US pulses was used to determine contrast flow through an image plane. Multigated power Doppler images were obtained following contrast injection. Contrast flow index (CFI) was determined by measuring the area under the color level vs. time curve for each gating frequency. CFI was compared with true flow. The method was first evaluated using a flow phantom with variable flow rates, and then verified in a mouse model with implanted tumors. Color levels in Doppler images were modulated with gating frequency due to variable destruction of microbubbles by US pulses. CFI measured from the images correlated strongly with true flow in the flow phantom (r(2) = 0.87). The proposed method yielded reproducible CFI for mice tumors, suggesting that multigated contrast-enhanced power Doppler imaging may provide noninvasive measurement of tumor perfusion in mice.


Assuntos
Aumento da Imagem , Neoplasias Experimentais/diagnóstico por imagem , Processamento de Sinais Assistido por Computador , Ultrassonografia Doppler em Cores/métodos , Animais , Feminino , Camundongos , Camundongos Endogâmicos C3H , Neoplasias Experimentais/irrigação sanguínea , Neovascularização Patológica/diagnóstico por imagem , Fluxo Sanguíneo Regional , Sensibilidade e Especificidade
17.
PLoS One ; 9(3): e90495, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24603893

RESUMO

Currently, no available pathological or molecular measures of tumor angiogenesis predict response to antiangiogenic therapies used in clinical practice. Recognizing that tumor endothelial cells (EC) and EC activation and survival signaling are the direct targets of these therapies, we sought to develop an automated platform for quantifying activity of critical signaling pathways and other biological events in EC of patient tumors by histopathology. Computer image analysis of EC in highly heterogeneous human tumors by a statistical classifier trained using examples selected by human experts performed poorly due to subjectivity and selection bias. We hypothesized that the analysis can be optimized by a more active process to aid experts in identifying informative training examples. To test this hypothesis, we incorporated a novel active learning (AL) algorithm into FARSIGHT image analysis software that aids the expert by seeking out informative examples for the operator to label. The resulting FARSIGHT-AL system identified EC with specificity and sensitivity consistently greater than 0.9 and outperformed traditional supervised classification algorithms. The system modeled individual operator preferences and generated reproducible results. Using the results of EC classification, we also quantified proliferation (Ki67) and activity in important signal transduction pathways (MAP kinase, STAT3) in immunostained human clear cell renal cell carcinoma and other tumors. FARSIGHT-AL enables characterization of EC in conventionally preserved human tumors in a more automated process suitable for testing and validating in clinical trials. The results of our study support a unique opportunity for quantifying angiogenesis in a manner that can now be tested for its ability to identify novel predictive and response biomarkers.


Assuntos
Inteligência Artificial , Carcinoma de Células Renais/patologia , Biologia Computacional/métodos , Células Endoteliais/patologia , Neoplasias Renais/patologia , Algoritmos , Carcinoma de Células Renais/irrigação sanguínea , Humanos , Neoplasias Renais/irrigação sanguínea , Aprendizagem Baseada em Problemas , Transdução de Sinais , Fatores de Tempo
18.
Cancer Biol Ther ; 10(12): 1326-33, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21079419

RESUMO

Vascular endothelial growth factor (VEGF) A is a major promoter of tumor angiogenesis and a prime target of antiangiogenic cancer therapy. To examine whether endothelial cell signaling might provide histological biomarkers of angiogenesis and VEGF activity in vivo, normal mouse organs and multiple tumor models were studied immunohistochemically for endothelial expression of activated ERK, STAT3, and AKT. Phospho(p)-ERK and p-STAT3 expression was negligible in the endothelia of normal organs but was significantly elevated in tumor endothelium. p-AKT was present at significant and comparable levels in both tumor and normal endothelia. In K1735 tumors induced to express more VEGF, endothelial p-ERK, p-STAT3 and p-AKT increased accompanied by signs of accelerated angiogenesis. Treatment of K1735 and Colo-205 tumors with the VEGF inhibitor, VEGF Trap (aflibercept), decreased tumor endothelial p-ERK, p-STAT3 and p-AKT expression accompanied by signs of antiangiogenic effect. These results show that endothelial p-ERK and p-STAT3 (but not p-AKT) distinguish tumor from normal vessels and that the presence of these two signaling intermediates may be useful indicators of tumor angiogenic activity and angiogenesis inhibition by VEGF antagonist.


Assuntos
Inibidores da Angiogênese/farmacologia , Células Endoteliais/metabolismo , Neoplasias Experimentais/metabolismo , Neovascularização Patológica , Proteínas Recombinantes de Fusão/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Linhagem Celular Tumoral , Doxiciclina/farmacologia , Células Endoteliais/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C3H , Camundongos SCID , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias Experimentais/irrigação sanguínea , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/genética , Proteína Oncogênica v-akt/genética , Proteína Oncogênica v-akt/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/genética
19.
Ultrasound Med Biol ; 36(5): 853-7, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20381952

RESUMO

The goal of this murine investigation was to evaluate the effect of an antivascular ultrasound treatment on the growth of an implanted melanoma and the consequent survival rate. After the intravenous injection of 0.2 mL ultrasound contrast agent (Definity), therapy (n = 15) was performed on 1-mL tumors for 3 min with low-intensity continuous ultrasound (3 MHz; 2.4 +/- 0.1 W cm(-2) [I(SATA)]); control mice (n = 17) received a sham treatment. Mice were euthanized once the tumor had reached 3 mL, and then survival percentage vs. time curves were plotted. The median survival time (time for tumor to reach 3 mL) for the treated group was 23 d and for the control group was 18 d; the difference was statistically significant (p

Assuntos
Melanoma/patologia , Melanoma/terapia , Neovascularização Patológica/patologia , Neovascularização Patológica/terapia , Terapia por Ultrassom/métodos , Animais , Linhagem Celular Tumoral , Camundongos , Camundongos Endogâmicos C3H , Análise de Sobrevida , Taxa de Sobrevida , Resultado do Tratamento
20.
Clin Liver Dis ; 14(4): 669-85, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21055689

RESUMO

Various technologies including nucleic acid, protein, and metabolic array analyses of blood, liver tissue, and bile are emerging as powerful tools in the study of hepatic pathophysiology. The entire lexicon of liver disease, however, has been written using classical hematoxylin-eosin staining and light microscopic examination. The authors' goal is to develop new tools to enhance histopathologic examination of liver tissue that would enrich the information gained from liver biopsy analysis, enable quantitative analysis, and bridge the gap between various "-omics" tools and interpretation of routine liver biopsy results. This article describes the progress achieved during the past 2 years in developing multiplex quantum dot (nanoparticle) staining and combining it with high-resolution whole-slide imaging using a slide scanner equipped with filters to capture 9 distinct fluorescent signals for multiple antigens. The authors first focused on precise characterization of leukocyte subsets, but soon realized that the data generated were beyond the practical limits that could be properly evaluated, analyzed, and interpreted visually by a pathologist. Therefore, the authors collaborated with the open source FARSIGHT image analysis project (http://www.farsight-toolkit.org). FARSIGHT's goal is to develop and disseminate the next-generation toolkit of automated image analysis methods to enable quantification of molecular biomarkers on a cell-by-cell basis from multiparameter images. The resulting data can be used for histocytometric studies of the complex and dynamic tissue microenvironments that are of biomedical interest. The authors envisage that these tools will eventually be incorporated into the routine practice of surgical pathology and precipitate a revolution in the specialty.


Assuntos
Biópsia/métodos , Imuno-Histoquímica/métodos , Hepatopatias/patologia , Processamento Eletrônico de Dados/instrumentação , Processamento Eletrônico de Dados/métodos , Humanos , Processamento de Imagem Assistida por Computador/instrumentação , Processamento de Imagem Assistida por Computador/métodos , Hepatopatias/diagnóstico , Pontos Quânticos
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