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1.
Clin Transl Oncol ; 22(4): 585-602, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31256361

RESUMO

PURPOSE: To determine whether cytomegalovirus is causally associated with breast cancer and whether cytomegalovirus should be categorised as an oncogenic virus. METHODS: We undertook a review of published epidemiological and laboratory studies, using established causal criteria: Bradford Hill criteria to determine whether cytomegalovirus is associated with breast cancer; and Evans/Mueller criteria to determine whether cytomegalovirus should be categorised as an oncogenic virus. RESULTS: Although there are inconsistencies in the findings of published epidemiological and laboratory studies, these may be explained by factors such as: differences in timing of blood samples, differences in selection of cases and controls, or high cytomegalovirus seroprevalence among participants in the epidemiological studies; and, in the laboratory studies, differences in sample preparations, age of sample, whether or not paired breast cancer and normal breast tissue samples were used, differences in the tests, primers and/or antibodies used, differences in histological types of breast cancer studied, and/or features of the virus. CONCLUSIONS: Overall, the results of published studies of cytomegalovirus and breast cancer suggest cytomegalovirus is a causal factor for at least some types of breast cancer. If the evidence for a link between cytomegalovirus and breast cancer continues to strengthen, further research could lead to: targeted screening; therapy using antiviral drugs; and, perhaps, primary prevention of a significant proportion of breast cancer. Vaccination against viruses has already been shown to be effective in preventing cervix and liver cancer; cytomegalovirus vaccines are already under development.


Assuntos
Neoplasias da Mama/virologia , Citomegalovirus/isolamento & purificação , Animais , Neoplasias da Mama/etiologia , Citomegalovirus/genética , Citomegalovirus/imunologia , Feminino , Humanos , Camundongos
2.
Ann Oncol ; 23(6): 1531-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22039086

RESUMO

BACKGROUND: In an ageing population, a greater proportion of geriatric patients will be considered for systemic chemotherapy. Colorectal cancer (CRC) is a common malignancy and will be a major health issue in geriatrics. We used the MAX population to investigate whether age affected the improved outcome found in CRC when bevacizumab is added to capecitabine chemotherapy. PATIENTS AND METHODS: MAX, a three arm study of Capecitabine (C) versus CBevacizumab (CB) versus CBMitomycin C (CBM), found an improvement in progression-free survival (PFS), with addition of B [+/- mitomycin C (MMC)] to C. This analysis assesses the effect of adding B (+/- MMC) to C on PFS, overall survival (OS), response rate (RR), toxicity and dose intensity in geriatric patients (age ≥ 75 years). RESULTS: Ninety-nine patients (21%) were aged 75-86 years. Baseline characteristics were well balanced. Eighty-eight per cent commenced C at the lower optional dose of 2000 mg/m(2)/day; days 1-14, q21 (61% for <75 years) and 88% were Eastern Cooperative Oncology Group 0-1. Co-morbidities were as expected in this population. The addition of B significantly improved PFS in geriatric patients(C 5.8 months versus CB 8.8 months, Hazard ratio (HR) 0.65 and C versus CBM 10.4 months HR 0.38). The interaction test for OS, RR and PFS revealed no impact of age. Dose intensity was maintained >90% in all patients. There were no major differences in toxicity patterns between age cohorts. CONCLUSIONS: Addition of B to C significantly improved PFS in this geriatric population, with similar benefits to those aged <75 years. Treatment was well tolerated with no signal of increased toxicity (including thromboembolism) when compared with those aged <75 years.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bevacizumab , Capecitabina , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/análogos & derivados , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Modelos Logísticos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/secundário , Masculino , Modelos de Riscos Proporcionais , Resultado do Tratamento
3.
Br J Cancer ; 104(1): 51-9, 2011 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-21081932

RESUMO

BACKGROUND: This study investigated the relationship of obesity, insulin resistance, inflammation and angiogenesis with cancer progression and survival in a colorectal cancer cohort. METHODS: Clinical and pathological data, along with anthropometric and follow-up data, were collected from 344 consecutive colorectal cancer patients. Serum samples at diagnosis were analysed by immunoassay for adiponectin, C-reactive protein (CRP), vascular endothelial growth factor-A (VEGF-A), angiopoietin-2 (Ang-2), insulin-like growth factor-1 (IGF-1), insulin and C-peptide. RESULTS: Serum Ang-2 and VEGF-A levels increased with tumour T stage (P=0.007 and P=0.025, respectively) and N stage (P=0.02 and P=0.03, respectively), and correlated with CRP levels (r=0.43, P<0.001 and r=0.23, P<0.001, respectively). Angiopoietin-2 correlated with C-peptide (r=0.14, P=0.007) and VEGF-A with IGF-1 in males (r=0.25, P=0.001). Kaplan-Meier analysis showed that patients with high serum levels of CRP and Ang-2 had significantly reduced survival (both P≤0.001). After adjusting for tumour stage and age, Ang-2 remained a significant predictor of survival. The CRP levels were inversely associated with survival in American Joint Committee on Cancer stage II patients (P=0.038), suggesting that CRP could be used to support treatment decisions in this subgroup. Serum markers and anthropometric measures of obesity correlated with each other, but not with survival. CONCLUSION: Our study supports the concept that obesity-related inflammation, rather than obesity itself, is associated with colorectal cancer progression and survival. The study confirms serum Ang-2 as a predictive marker for outcome of colorectal cancer.


Assuntos
Adenocarcinoma/mortalidade , Angiopoietina-2/sangue , Biomarcadores/metabolismo , Proteína C-Reativa/metabolismo , Neoplasias Colorretais/mortalidade , Resistência à Insulina , Obesidade/sangue , Adenocarcinoma/sangue , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Peptídeo C/sangue , Neoplasias Colorretais/sangue , Neoplasias Colorretais/patologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taxa de Sobrevida , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/sangue
4.
Intern Med J ; 39(12): 819-25, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19220527

RESUMO

BACKGROUND: Venous thromboembolism (VTE) is a significant problem in oncology patients. VTE prophylaxis is underutilized in hospitalized medical patients, but there are few data for the appropriateness and frequency of its use in the oncology subgroup. We aimed to document local practice. METHODS: A cross-sectional chart review of all hospitalized patients cared for by the Christchurch Hospital Oncology Service was carried out during two defined 4-week periods. Assessment for indications and contraindications to prophylactic anticoagulation was based on the 2004 American College of Chest Physicians evidence-based consensus guidelines. RESULTS: Of 113 admissions to the oncology service, 38 (33.6%) had indications for prophylactic anticoagulation. However, 23 of these also had contraindications, leaving only 15 (13%) admissions where prophylactic anticoagulation was deemed appropriate. Only one was appropriately given prophylactic anticoagulation. CONCLUSION: Only a minority of hospitalized oncology patients are appropriate for prophylactic anticoagulation. Where it is suitable, however, it is poorly utilized locally. Local promotion of VTE prophylaxis and further study of this subgroup of hospitalized medical patients may improve uptake of this practice and attenuate morbidity from VTE.


Assuntos
Anticoagulantes/uso terapêutico , Neoplasias/complicações , Padrões de Prática Médica , Trombose Venosa/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Comissão Para Atividades Profissionais e Hospitalares , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
J Pathol ; 212(3): 335-44, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17487938

RESUMO

Thymidine phosphorylase (TP) is an angiogenic enzyme, catalysing the reversible phosphorylation of thymidine to thymine and 2-deoxyribose. TP is up-regulated in neoplasia, being associated with advanced tumour stage, microvessel density and prognosis in several tumour types. Although TP is a non-mitogenic migratory factor for endothelium, the mechanism by which TP mediates these effects is still unclear. We compared the gene expression profile of endothelial cells grown in vitro in the presence or absence of TP by cDNA microarray analysis. To determine the time-course of TP angiogenic induction, endothelial cells were stimulated with TP (10 ng/ml) for 5 and 18 h. Gene expression levels of Tie2, angiopoietin (Ang)1 and Ang2, measured by RNase protection assay (RPA), showed maximal alteration at 18 h. cDNA from human umbilical vein endothelial cells (HUVEC) grown for 18 h in the presence or absence of TP (10 ng/ml) was hybridized to a human cDNA cytokine array representing 375 angiogenic genes. Significantly altered expression occurred in 89 human angiogenic genes (72 genes were up-regulated and 17 down-regulated). Changes in five genes relevant to vascular remodelling biology (Tie2, nNos, P-selectin, ephrin-B1 and TP) were validated in triplicate experiments by real-time RT-PCR. But only P-selectin gene expression remained significant. Correlation between P-selectin and TP was assessed by immunohistochemistry on 161 human breast cancers, using human tissue microarray. Tumour cell TP correlated with tumour cell P-selectin but not with endothelial cell P-selectin. These data show that TP stimulates changes in mRNA expression maximally after 18 h culture in vitro. It confirms a role for TP in vascular remodelling involving several classes of genes, including the cell adhesion molecule, P-selectin. Although confirmation of the role of TP-mediated cell adhesion molecule (CAM) induction is required; however, this pathway may provide an attractive therapeutic target, since it is likely to affect several important tumour processes, including angiogenesis and metastasis.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Células Endoteliais/metabolismo , Regulação Neoplásica da Expressão Gênica , Selectina-P/metabolismo , Timidina Fosforilase/metabolismo , Sequência de Bases , Neoplasias da Mama/química , Carcinoma Ductal de Mama/química , Primers do DNA/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização In Situ/métodos , Dados de Sequência Molecular , Neovascularização Patológica/genética , Análise de Sequência com Séries de Oligonucleotídeos , Selectina-P/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Timidina Fosforilase/análise
7.
J Clin Pathol ; 57(8): 829-34, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15280403

RESUMO

BACKGROUND: Vascular endothelial growth factor D (VEGF-D) induces angiogenesis and lymphangiogenesis. Nodal metastasis is recognised as a powerful prognostic marker in breast carcinoma, but the molecular mechanisms underlying this process are unknown. Although it has been suggested that VEGF-D may regulate nodal metastasis, this is based largely on animal models, its role in human disease being unclear. AIMS: To measure the pattern and degree of VEGF-D protein expression in normal and neoplastic human breast tissues. METHODS: The pattern and degree of VEGF-D expression was measured in normal tissue and invasive carcinomas, and expression was correlated with clinicopathological parameters, hypoxia markers, and survival. Because other VEGF family members are affected by oestrogen, whether VEGF-D is regulated by oestrogen in breast cancer cell lines was also assessed. RESULTS: VEGF-D was significantly positively associated with hypoxia inducible factor (HIF-1alpha) (p = 0.03) and the HIF-1alpha regulated gene DEC1 (p = 0.001), but not lymph node status, the number of involved lymph nodes, patient age, tumour size, tumour grade, lymphovascular invasion, oestrogen receptor, progesterone receptor, c-erb-B2, or tumour histology (all p>0.05). There was no significant relation between tumour VEGF-D expression and relapse free (p = 0.78) or overall (p = 0.94) survival. VEGF-D expression was enhanced by oestrogen in MCF-7 and T47D breast cancer cells, and was blocked by hydroxytamoxifen. CONCLUSION: These findings support a role for hypoxia and oestrogen induced VEGF-D in human breast cancer and also suggest that tamoxifen and related oestrogen antagonists may exert some of their antitumour effects through the abrogation of VEGF-D induced function.


Assuntos
Neoplasias da Mama/química , Carcinoma/química , Tamoxifeno/análogos & derivados , Fatores de Transcrição/análise , Proteínas Supressoras de Tumor/genética , Fator D de Crescimento do Endotélio Vascular/análise , Neoplasias da Mama/mortalidade , Carcinoma/mortalidade , Estudos de Casos e Controles , Linhagem Celular Tumoral/química , Distribuição de Qui-Quadrado , Intervalo Livre de Doença , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia , Imuno-Histoquímica , Metástase Linfática , Pessoa de Meia-Idade , Taxa de Sobrevida , Tamoxifeno/farmacologia
8.
Clin Cancer Res ; 7(4): 918-27, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11309342

RESUMO

PURPOSE: Angiogenesis is essential for tumor growth and metastasis. It is a complex, dynamic process that is coordinated by several classes of angiogenic factors. One candidate family is the Tie2 tyrosine kinase, whose expression is restricted largely to endothelial cells. Tie2 has three known ligands, angiopoietin (Ang)-1, Ang-2, and Ang-4, that have different functional effects but play a requisite role in embryonic vessel remodeling. Because there are only limited data on the Tie2 pathway in human breast cancer, and our previous data have suggested that breast tumors establish a blood supply by vascular remodeling, we have investigated the expression of Ang-1, Ang-2, Ang-4, and Tie2 in a series of normal and neoplastic human breast tissues. EXPERIMENTAL DESIGN: We examined mRNA expression by reverse transcription-PCR in 6 normal and 52 malignant breast tissues and correlated expression with clinicopathological and angiogenic variables. We also examined the effect of physiological levels of estrogen on Ang expression. RESULTS: Ang-1, Ang-2, Ang-4, and Tie2 were detected in 19%, 52%, 35%, and 65%, respectively, of tumor samples. There was a significant reduction in expression of tumor Ang-1 (P = 0.04), Ang-2 (P = 0.01), Ang-4 (P = 0.004), and Tie2 (P = 0.02) compared with that in normal breast tissues. There was a significant relationship in tumors between all Angs and between each ligand and Tie2. In a multivariate analysis, there were significant positive correlations between Ang-4 and estrogen receptor (P = 0.016) and a significant inverse correlation between Ang-1 and thymidine phosphorylase expression (P = 0.01). No significant associations were observed between the other members of the Ang/Tie2 gene family and patient age, tumor size, lymph node status, tumor grade, vascular invasion, tumor vascularity, vascular maturation, thymidine phosphorylase, or vascular endothelial growth factor A expression (P > 0.05 for all). The potential regulation of Ang-4 by estrogen was further investigated in vitro. Addition of physiological concentrations of 17beta-estradiol (1 nM) to hormone-free media caused no significant change in Ang-4 mRNA abundance (P = 0.75) in the estrogen receptor-positive cell line MCF-7 after either 2 or 18 h, despite demonstrating induction for the estrogen response gene pS2. CONCLUSIONS: These findings suggest that the Ang/Tie2 pathway plays a significant role in human breast tumor angiogenesis but provide no initial evidence for direct regulation of the pathway by estrogen.


Assuntos
Angiopoietinas , Neoplasias da Mama/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular , Glicoproteínas de Membrana/metabolismo , Neovascularização Patológica/metabolismo , Proteínas Proto-Oncogênicas , Timidina Fosforilase/biossíntese , Angiopoietina-1 , Angiopoietina-2 , Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Estrogênios/farmacologia , Feminino , Expressão Gênica/efeitos dos fármacos , Substâncias de Crescimento/genética , Substâncias de Crescimento/metabolismo , Humanos , Imuno-Histoquímica , Glicoproteínas de Membrana/genética , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas/genética , Proteínas/metabolismo , RNA Mensageiro/biossíntese , Receptor TIE-2 , Células Tumorais Cultivadas
9.
Cancer Res ; 61(7): 3206-11, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11306510

RESUMO

Angiogenesis is essential for tumor growth and metastasis. It is regulated by numerous angiogenic factors, one of the most important being vascular endothelial growth factor (VEGF). Recently VEGF-B and VEGF-C, two new VEGF family members, have been identified that bind to the tyrosine kinase receptors flt-1 (VEGFR1), KDR (VEGFR2), and flt-4 (VEGFR3). Although the importance of VEGF-A has been shown in renal carcinomas, the contribution of these new ligands in kidney tumors is not clear. We have, therefore, measured the mRNA level of VEGF-B and VEGF-C together with their receptors by RNase protection assay (RPA) in 26 normal kidney samples and 45 renal cell cancers. We observed a significant up-regulation of VEGF-B (P = 0.002) but not VEGF-C (P = 0.3) in neoplastic kidney compared with normal tissues. In addition, although VEGF receptors were higher in tumors than normal kidney, there was a significant up-regulation of only flt-1 (P = 0.003) but not KDR (P = 0.12) or flt-4 (P = 0.09). There was also a significant correlation between VEGF-C and both of its receptors flt-4 (P = 0.006) and KDR (P = 0.03) but no association between VEGF-B and its receptor flt-1 (P = 0.23). A significant increase was observed in flt-1 (P < 0.001), KDR (P = 0.02), and flt-4 (P = 0.01) but not VEGF-B (P = 0.82) or VEGF-C (P = 0.52) expression in clear cell compared with chromophil (papillary) carcinomas. No significant association was demonstrated between VEGF-B, VEGF-C, flt-1, KDR, and flt-4 with patient sex, patient age, or tumor size (P > 0.05). The effect of von Hippel-Lindau (VHL) gene and hypoxia on VEGF-B and VEGF-C expression in the renal carcinoma cell line 786-0 transfected with wild-type and mutant VHL was determined by growing cells under 21% O2- and 0.1% O2. In wild-type VHL cells, whereas VEGF-A was significantly up-regulated under hypoxic compared with normoxic conditions (P < 0.001), expression of VEGF-C was reduced (P < 0.002). Nevertheless, the repression of VEGF-C was lost in mutant VHL cell lines under hypoxia. In contrast VEGF-B was not regulated by VHL despite clear up-regulation in vivo. These findings strongly support an enhanced role for this pathway in clear cell carcinomas by regulating angiogenesis and/or lymphangiogenesis. The study shows that clear cell tumors are able to up-regulate angiogenic growth factor receptors more efficiently than chromophil (papillary), that clear cell tumors can use pathways independent of VHL to regulate angiogenesis, and that this combined regulation may account for their more aggressive phenotype, which suggests that targeting VEGFR1 (flt-l) may be particularly effective in these tumor types.


Assuntos
Carcinoma de Células Renais/metabolismo , Fatores de Crescimento Endotelial/biossíntese , Genes Supressores de Tumor , Neoplasias Renais/metabolismo , Ligases , Proteínas/genética , Proteínas Supressoras de Tumor , Ubiquitina-Proteína Ligases , Adenocarcinoma de Células Claras/genética , Adenocarcinoma de Células Claras/metabolismo , Adenocarcinoma de Células Claras/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Papilar/genética , Carcinoma Papilar/metabolismo , Carcinoma Papilar/patologia , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Hipóxia Celular/fisiologia , Fatores de Crescimento Endotelial/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Rim/metabolismo , Neoplasias Renais/genética , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas/genética , Receptores Proteína Tirosina Quinases/biossíntese , Receptores Proteína Tirosina Quinases/genética , Receptores de Fatores de Crescimento/biossíntese , Receptores de Fatores de Crescimento/genética , Receptores de Fatores de Crescimento do Endotélio Vascular , Transfecção , Fator B de Crescimento do Endotélio Vascular , Fator C de Crescimento do Endotélio Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Receptor 3 de Fatores de Crescimento do Endotélio Vascular , Proteína Supressora de Tumor Von Hippel-Lindau
10.
J Pathol ; 193(3): 325-32, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11241411

RESUMO

Angiogenesis is essential for tumour growth and metastasis. It is regulated by numerous angiogenic factors, one of the most important being vascular endothelial growth factor (VEGF). Recently VEGF-B, a new VEGF family member that binds to the tyrosine kinase receptor flt-1, has been identified. Although the importance of VEGF has been shown in many human tumour types, the contribution of VEGF-B to tumour neovascularization is unknown in any tumour type. This study therefore measured the mRNA level of VEGF-B and its receptor flt-1 by ribonuclease protection assay and the pattern of VEGF-B expression by immunohistochemistry in 13 normal breast samples and 68 invasive breast cancers. Flt-1 expression was significantly higher in tumours than in normal breast (p=0.02) but no significant difference was seen in VEGF-B between normal and neoplastic breast (p=0.3). There was a significant association between VEGF-B and node status (p=0.02) and the number of involved nodes (p=0.01), but not with age (p=0.7), size (p=0.6), oestrogen receptor (ER) (p=0.2), grade (p=0.5) or vascular invasion (p=0.16). No significant relationship was present between VEGF-B and flt-1 (p=0.2) or tumour vascularity (p=0.4). VEGF-B was expressed mostly in the cytoplasm of tumour cells, although occasional stromal components including fibroblasts and endothelial cells were also positive. No difference in VEGF-B expression was observed adjacent to regions of necrosis, in keeping with this VEGF family member not being hypoxically regulated. These findings suggest that VEGF-B may contribute to tumour progression by a non-angiogenic mechanism, possibly by increasing plasminogen activators and hence metastasis, as has been described in vitro. Measurement of VEGF-B together with other angiogenic factors may identify a poor prognostic patient group, which may benefit from anti-VEGF receptor therapy targeted to flt-1 (VEGFR1) as well as kdr (VEGFR2).


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Fatores de Crescimento Endotelial/metabolismo , Neovascularização Patológica/metabolismo , Adulto , Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/irrigação sanguínea , Carcinoma Ductal de Mama/patologia , Fatores de Crescimento Endotelial/genética , Feminino , Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Metástase Linfática , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Neoplásico/genética , Ribonucleases/genética , Fator B de Crescimento do Endotélio Vascular
11.
Clin Cancer Res ; 6(11): 4278-86, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11106244

RESUMO

Angiogenesis is essential for tumor growth and metastasis. It is regulated by numerous angiogenic factors, one of the most important being vascular endothelial growth factor (VEGF). Recently, VEGF-C, a new VEGF family member, has been identified that binds to the tyrosine kinase receptors flt-4 [VEGF receptor (VEGFR) 3] and KDR (VEGFR2). Although the importance of VEGF has been shown in many human tumor types, the contribution of VEGF-C and its primary receptor flt-4 to tumor progression is less well understood. We have therefore measured the level of VEGF-C, flt-4, and KDR mRNA by RNase protection assay and the pattern of VEGF-C expression by immunohistochemistry in 11 normal breast tissue samples and 61 invasive breast cancers. No significant difference in VEGF-C expression was observed between normal and neoplastic breast tissues (P = 0.11). There was a significant correlation between VEGF-C and both flt-4 (P = 0.02) and KDR (P = 0.0002), but no association was seen between VEGF-C and either lymph node status (P = 0.66) or number of involved nodes (P = 0.88), patient age (P = 0.83), tumor size (P = 0.20), estrogen receptor status (P = 0.67), or tumor grade (P = 0.35). No significant relationship was present between VEGF-C and vascular invasion (P = 0.30), tumor vascularity (P = 0.21), VEGF-A (P = 0.62), or thymidine phosphorylase expression (P = 1.00). VEGF-C was expressed predominantly in the cytoplasm of tumor cells, although occasional stromal components including fibroblasts were also positive. We could demonstrate no association between lymph node metastasis and either VEGF-C (P = 0.66) or flt-4 (P = 0.4). However, we did observe a significant loss of the long but not the short isoform of flt-4 in tumors compared with normal tissues (P = 0.02 and P = 0.25, respectively), and this difference was largely accounted for by the reduction of long flt-4 in node-positive tumors. These findings strongly support a role for VEGF-C/flt-4 signaling in tumor growth by enhancement of angiogenesis and/or lymphangiogenesis and suggest that differential regulation of these processes may be controlled via flt-4 isoform transcription. They further suggest that the measurement of flt-4 isoform expression may identify a patient group that is likely to have node-positive disease and therefore benefit from additional treatment and also emphasize an additional ligand interaction that could be exploited by anti-VEGFR therapy.


Assuntos
Neoplasias da Mama/irrigação sanguínea , Fatores de Crescimento Endotelial/fisiologia , Receptores Proteína Tirosina Quinases/fisiologia , Receptores de Fatores de Crescimento/fisiologia , Processamento Alternativo , Neoplasias da Mama/patologia , Fatores de Crescimento Endotelial/genética , Feminino , Humanos , Imuno-Histoquímica , Metástase Linfática , Neovascularização Patológica/etiologia , RNA Mensageiro/análise , Receptores Proteína Tirosina Quinases/análise , Receptores Proteína Tirosina Quinases/genética , Receptores de Fatores de Crescimento/análise , Receptores de Fatores de Crescimento/genética , Receptores de Fatores de Crescimento do Endotélio Vascular , Fator C de Crescimento do Endotélio Vascular , Receptor 3 de Fatores de Crescimento do Endotélio Vascular
12.
Pathology ; 32(1): 21-3, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10740800

RESUMO

Lymphadenopathy associated with hemorrhage as a presenting feature of primary (AL) amyloidosis has not previously been described. We report two such cases one of whom had an acquired factor X and IX deficiency. The clinical presentations were characterized by sudden spontaneous enlargement of lymph nodes followed by partial regression. In both cases significant delay in diagnosis, and hence treatment, occurred due to the mode of presentation. One patient died with rapidly progressive disease but the other has had an excellent response to therapy with high-dose melphalan (HDM, 200 mg/m2) and peripheral blood stem cell rescue. AL amyloid should be considered in all patients presenting with hemorrhagic lymphadenopathy.


Assuntos
Amiloidose/diagnóstico , Hemorragia/diagnóstico , Doenças Linfáticas/diagnóstico , Adulto , Amiloide/metabolismo , Amiloidose/metabolismo , Amiloidose/terapia , Diagnóstico Diferencial , Deficiência do Fator X/diagnóstico , Evolução Fatal , Transplante de Células-Tronco Hematopoéticas , Hemofilia B/diagnóstico , Hemorragia/metabolismo , Hemorragia/terapia , Humanos , Fígado/química , Fígado/patologia , Doenças Linfáticas/metabolismo , Doenças Linfáticas/terapia , Masculino , Melfalan/uso terapêutico , Microscopia de Polarização , Pessoa de Meia-Idade
14.
Mol Pathol ; 51(6): 339-41, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10193515

RESUMO

Cowden disease is an autosomal dominant disorder associated with an increased risk of breast, thyroid, and skin cancer in which germline mutations in a candidate tumour suppressor gene (PTEN) have been identified previously. Sjögren's syndrome is a chronic inflammatory and autoimmune disorder of exocrine glands for which the genetic basis is unknown. This report describes a novel PTEN mutation (L139X) in a patient with Cowden disease and Sjögren's syndrome. This observation raises the possibility of a link between mutations in the PTEN gene and Sjögren's syndrome.


Assuntos
Mutação em Linhagem Germinativa , Síndrome do Hamartoma Múltiplo/genética , Monoéster Fosfórico Hidrolases/genética , Síndrome de Sjogren/genética , Proteínas Supressoras de Tumor , Adulto , Feminino , Humanos , PTEN Fosfo-Hidrolase , Linhagem
15.
Clin Pharmacokinet ; 33(3): 161-83, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9314610

RESUMO

Carboplatin shares some of the therapeutic advantages of cisplatin, but without a significant incidence of the dose-limiting neurotoxicity and nephrotoxicity which is experienced with cisplatin. However, its use is associated with dose-limiting bone marrow suppression. Carboplatin is present in the blood as 3 distinct species. These are total platinum and 2 unbound species, carboplatin itself and a decarboxylated platinum-containing degradation product. The 2 main methods used to assay the unbound species are flameless atomic absorption spectrophotometry and high performance liquid chromatography. The first of these methods assays both unbound platinum species, the second is specific for carboplatin. Both unbound species have similar pharmacokinetic profiles for the first 12 hours post-dose. Carboplatin appears to have a linear pharmacokinetic profile over the doses used clinically and does not interact significantly with drugs that are used commonly in combination chemotherapy. The pharmacokinetics of carboplatin are adequately described by an open 2-compartment model with elimination from the central compartment. Its clearance is proportional to the glomerular filtration rate and the volume of distribution of the central compartment appears to correlate with extracellular fluid volume. The elimination half-life varies with renal function and is typically between 2 and 6 hours in patients with a normal glomerular filtration rate and may be as long as 18 hours in patients with impaired renal function. Relationships between systemic exposure to carboplatin, described as the area under the concentration-time curve (AUC), and both toxicity and response have been described. For toxicity the strongest evidence exists for a relationship between AUC and thrombocytopenia. To a lesser extent the relationship between AUC and neutropenia has also been described. Patients already treated with platinum analogues have been shown to develop a greater degree of myelosuppression from any given AUC. In addition, some evidence suggests a relationship between the shape of the concentration-time curve and myelotoxicity, where constant infusions appear less likely to cause myelosuppression on a mg/m2 dose administration basis. The relationship between AUC and response rate is not as clear, this may be related to the lack of studies describing both the dose and AUC of carboplatin. There appears to be a more clearly defined AUC-response relationship for ovarian cancer than for other malignancies, with an AUC of between 5 and 7 mg/ml.min being associated with the maximal response rate [located at the plateau on an AUC-response curve]. However, new data suggest that higher AUCs may lead to greater response rates. Data from testicular cancer also strongly supports an AUC-response relationship with an increased number of treatment failures with carboplatin AUCs < 5 to 6 mg/ml.min. Given the AUC-effect relationships described above a number of studies have been performed to develop models to describe the relationship between both dose and AUC and dose and platelet nadir. In adults, perhaps the most common method is that of Calvert which describes the relationship between dose and AUC. Paediatric formulas have also been described. More recently a number of limited sampling strategies have been proposed as well as Bayesian dose individualisation techniques.


Assuntos
Antineoplásicos/farmacocinética , Carboplatina/farmacocinética , Adulto , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Antineoplásicos/sangue , Área Sob a Curva , Teorema de Bayes , Carboplatina/administração & dosagem , Carboplatina/efeitos adversos , Carboplatina/sangue , Criança , Cromatografia Líquida de Alta Pressão , Ensaios Clínicos como Assunto , Relação Dose-Resposta a Droga , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Meia-Vida , Humanos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Neutropenia/induzido quimicamente , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/tratamento farmacológico , Espectrofotometria Atômica , Neoplasias Testiculares/sangue , Neoplasias Testiculares/tratamento farmacológico , Trombocitopenia/induzido quimicamente
16.
Pathology ; 29(3): 294-9, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9271021

RESUMO

Hodgkin's cells (HC) are considered to be the malignant cells of Hodgkin's disease (HD), but despite extensive studies, no conclusive evidence has emerged regarding their non-malignant counterpart and the ontogeny of these cells remains controversial. The analysis of a possible dendritic cell (DC) origin of HC has been hampered to date by the lack of a DC lineage specific marker. The expression of the two DC-associated antigens CD83 and CMRF-44, the B lymphocyte restricted molecule CD79, and the costimulator molecule CD86, was examined in lymph nodes from 23 HD patients using immunohistological techniques. The majority of HC expressed the CD83 (22/23) and CD86 antigens (20/23), whereas expression of the CMRF-44 antigen was variable (10/23) and usually only a subpopulation of HC stained. In contrast, the CD79 antigen was absent from most HC (17/23). The presence of the CD83 antigen on HC in the absence of the CD79 antigen supports a possible DC lineage origin for some HC. Regardless of its role in lineage assignment, CD83 may become a useful immunohistological marker for HD as the CD83 antigen was present on most HC.


Assuntos
Antígenos CD/análise , Células Dendríticas/imunologia , Doença de Hodgkin/patologia , Imunoglobulinas/análise , Glicoproteínas de Membrana/análise , Anticorpos Monoclonais , Linhagem da Célula , Doença de Hodgkin/imunologia , Humanos , Técnicas Imunoenzimáticas , Imunofenotipagem , Antígeno CD83
17.
Cancer Chemother Pharmacol ; 39(4): 317-26, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9025772

RESUMO

Carboplatin is associated with significantly less nephrotoxicity and neurotoxicity than is cisplatin. The dose-limiting toxicity of carboplatin is myelotoxicity. A number of dosing methods have been described that allow a value for the area under the concentration-time curve to be targeted on the basis of the patient's renal function. Recently a formalised analysis of the pharmacodynamic response to carboplatin revealed a therapeutic window in which the response rate was maximal and toxicity, tolerable. Optimal therapy would result from targeting this window in the individual patient. The aim of this study was to develop a Bayesian dose-individualisation method for carboplatin. The method involved (1) development of a high-performance liquid chromatography (HPLC) method to measure serum concentrations of carboplatin; (2) a pharmacokinetic study in 12 women receiving carboplatin for ovarian cancer to estimate the population pharmacokinetic values for this group of patients; (3) development of population models to describe the concentration-time course of carboplatin in serum along with associated errors; and (4) development of an algorithm that uses a sequential Bayesian design, which enables estimation of future doses of carboplatin on the basis of feedback from serum concentrations. The results of each of the stages were (1) the coefficient of variation of the assay was 6.3% within day and 8.4% between days (r2 = 0.9993), and the limit of detection was 0.25 mg/l; (2) Patients' ages ranged from 49 to 68 years, their weights varied from 46 to 85 kg, and their glomerular filtration rate ranged from 3.2 to 7.4 l/h. A geometric mean clearance (Cl) of 6.8 L/h and a steady-state volume of distribution (Vss) of 221 were estimated, which are similar to previously published data; (3) and a two-compartment model best described the data. Two error models were developed, the first describing the error associated with the assay and the second, the error of the two-compartment model, i.e. error due to individual variation in pharmacokinetics and error due to model mis-specification. Finally, (4) the development of a sequential Bayesian dose-individualisation method for carboplatin is described. To our knowledge, this is the first sequential design that has been used for dose individualisation of chemotherapy. The program is specific for carboplatin and operates independently of commercially available Bayesian software. Doses predicted by this program are being tested prospectively against conventional dosing methods.


Assuntos
Antineoplásicos/administração & dosagem , Carboplatina/administração & dosagem , Modelos Biológicos , Idoso , Antineoplásicos/sangue , Antineoplásicos/farmacocinética , Teorema de Bayes , Carboplatina/sangue , Carboplatina/farmacocinética , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Pessoa de Meia-Idade , Método de Monte Carlo
18.
Aust N Z J Med ; 24(4): 368-73, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7980232

RESUMO

AIM: To determine the incidence of second malignant neoplasms in patients treated for Hodgkin's disease. METHODS: The records were reviewed of all patients receiving primary treatment for Hodgkin's disease at the Oncology Service, Christchurch Hospital from 1969 to 1992. Second malignant neoplasms presenting at least six months after the diagnosis of Hodgkin's disease were noted and the cumulative risk estimated. RESULTS: Twenty-two second malignant neoplasms developed in 20 of the 209 patients. The risk was 5.6 +/- 3.8% (CI) at five years, 11.4 +/- 6.2% at ten years, and 21.7 +/- 11.2% at 15 years and continued to increase thereafter. Thirteen patients have died of their second malignancy, including two of a third malignancy, while four have been followed for less than one year. Three leukaemias (CML, 1; acute non lymphocytic leukaemia, 2), three lymphomas and 16 solid tumours developed. The risk was greater after six or more cycles of MOPP-like chemotherapy and after radiation doses exceeding 30 Gray. The risk was less after laparotomy and splenectomy (p = 0.0205). CONCLUSIONS: In view of the significant risk of a second neoplasm in survivors of Hodgkin's disease follow up should continue beyond ten years, after which time second malignancies were more likely than recurrence. Efforts should continue to minimise the carcinogenicity of therapy while preserving efficacy.


Assuntos
Doença de Hodgkin/terapia , Segunda Neoplasia Primária/epidemiologia , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Clorambucila/administração & dosagem , Terapia Combinada , Feminino , Humanos , Incidência , Masculino , Mecloretamina/administração & dosagem , Pessoa de Meia-Idade , Nova Zelândia/epidemiologia , Prednisona/administração & dosagem , Procarbazina/administração & dosagem , Dosagem Radioterapêutica , Fatores de Risco , Fatores de Tempo , Vimblastina/administração & dosagem , Vincristina/administração & dosagem
19.
20.
Obstet Gynecol ; 82(5): 787-96, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8105432

RESUMO

OBJECTIVE: To assess the influence of human immunodeficiency virus (HIV) infection on pregnancy outcome and the effect of pregnancy on the short-term course of HIV infection. METHODS: Pregnant women with identified risk factors for HIV infection but without AIDS were tested serologically for HIV antibodies. Seropositive women were compared to seronegative patients with similar risk factors and demographic characteristics at enrollment, at delivery, and 6-8 weeks postpartum. One hundred one seropositive and 97 seronegative subjects were evaluated for symptoms or physical manifestations of HIV infection; evidence of immune dysfunction; historical, physical, or laboratory evidence of related infections; and maternal and neonatal outcome. Both groups were compared to the entire obstetric population delivering at the University of Maryland Hospital during 1 year. RESULTS: There was a significant reduction in reported risk behaviors in both groups during pregnancy as compared to the period before pregnancy (P < .001). The majority of women in both groups were asymptomatic, but seropositive women were more likely to have a history or physical evidence of condylomata (13 versus 4%; P < .05) and higher temperatures on admission to the labor suite (98.6 +/- 1.0 versus 98.3 +/- 0.8F; P = .02). Seropositive women were not at greater risk for antepartum medical complications. Only one woman developed an AIDS-defining opportunistic infection. Although hematologic indices in seropositive women were abnormal, these did not progress over the course of pregnancy. At delivery, seropositive women were more likely to receive antibiotics (25 versus 10%; P = .006) and less likely to have an episiotomy (25 versus 40%; P = .03), but obstetric outcome was unaffected. Neonatal status was independent of antibody status. CONCLUSION: Our findings support a growing body of evidence that pregnancy has no discernible effect on the early progression of HIV disease in asymptomatic women, and infection does not influence perinatal outcome.


Assuntos
Soropositividade para HIV/complicações , Complicações Infecciosas na Gravidez , Resultado da Gravidez , Adulto , Linfócitos T CD4-Positivos , Feminino , Soropositividade para HIV/imunologia , Humanos , Contagem de Leucócitos , Gravidez , Complicações Infecciosas na Gravidez/imunologia , Prognóstico , Fatores de Risco , Linfócitos T Reguladores
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