RESUMO
Diagnosis and assessment of patients with prostate cancer is dependent on accurate interpretation and grading of histopathology. However, morphology does not necessarily reflect the complex biological changes occurring in prostate cancer disease progression, and current biomarkers have demonstrated limited clinical utility in patient assessment. This study aimed to develop biomarkers that accurately define prostate cancer biology by distinguishing specific pathological features that enable reliable interpretation of pathology for accurate Gleason grading of patients. Online gene expression databases were interrogated and a pathogenic pathway for prostate cancer was identified. The protein expression of key genes in the pathway, including adaptor protein containing a pleckstrin homology (PH) domain, phosphotyrosine-binding (PTB) domain, and leucine zipper motif 1 (Appl1), Sortilin and Syndecan-1, was examined by immunohistochemistry (IHC) in a pilot study of 29 patients with prostate cancer, using monoclonal antibodies designed against unique epitopes. Appl1, Sortilin, and Syndecan-1 expression was first assessed in a tissue microarray cohort of 112 patient samples, demonstrating that the monoclonal antibodies clearly illustrate gland morphologies. To determine the impact of a novel IHC-assisted interpretation (the utility of Appl1, Sortilin, and Syndecan-1 labelling as a panel) of Gleason grading, versus standard haematoxylin and eosin (H&E) Gleason grade assignment, a radical prostatectomy sample cohort comprising 114 patients was assessed. In comparison to H&E, the utility of the biomarker panel reduced subjectivity in interpretation of prostate cancer tissue morphology and improved the reliability of pathology assessment, resulting in Gleason grade redistribution for 41% of patient samples. Importantly, for equivocal IHC-assisted labelling and H&E staining results, the cancer morphology interpretation could be more accurately applied upon re-review of the H&E tissue sections. This study addresses a key issue in the field of prostate cancer pathology by presenting a novel combination of three biomarkers and has the potential to transform clinical pathology practice by standardising the interpretation of the tissue morphology.
Assuntos
Neoplasias da Próstata , Sindecana-1 , Humanos , Masculino , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Anticorpos Monoclonais , Gradação de Tumores , Projetos Piloto , Neoplasias da Próstata/metabolismo , Reprodutibilidade dos Testes , Sindecana-1/metabolismoRESUMO
Dysregulated lipid metabolism is a prominent feature of prostate cancer that is driven by androgen receptor (AR) signaling. Here we used quantitative mass spectrometry to define the "lipidome" in prostate tumors with matched benign tissues (n = 21), independent unmatched tissues (n = 47), and primary prostate explants cultured with the clinical AR antagonist enzalutamide (n = 43). Significant differences in lipid composition were detected and spatially visualized in tumors compared with matched benign samples. Notably, tumors featured higher proportions of monounsaturated lipids overall and elongated fatty acid chains in phosphatidylinositol and phosphatidylserine lipids. Significant associations between lipid profile and malignancy were validated in unmatched samples, and phospholipid composition was characteristically altered in patient tissues that responded to AR inhibition. Importantly, targeting tumor-related lipid features via inhibition of acetyl-CoA carboxylase 1 significantly reduced cellular proliferation and induced apoptosis in tissue explants. This characterization of the prostate cancer lipidome in clinical tissues reveals enhanced fatty acid synthesis, elongation, and desaturation as tumor-defining features, with potential for therapeutic targeting. SIGNIFICANCE: This study identifies malignancy and treatment-associated changes in lipid composition of clinical prostate cancer tissues, suggesting that mediators of these lipidomic changes could be targeted using existing metabolic agents.
Assuntos
Metabolismo dos Lipídeos , Lipidômica , Lipídeos de Membrana/metabolismo , Neoplasias da Próstata/metabolismo , Biomarcadores , Biologia Computacional/métodos , Metabolismo Energético , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipidômica/métodos , Masculino , Metabolômica/métodos , Terapia de Alvo Molecular , Gradação de Tumores , Estadiamento de Neoplasias , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/etiologia , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em Tandem , Regulador Transcricional ERG/genética , Regulador Transcricional ERG/metabolismoRESUMO
Patient-derived explant (PDE) culture of solid tumors is increasingly being applied to preclinical evaluation of novel therapeutics and for biomarker discovery. In this technique, treatments are added to culture medium and penetrate the tissue via a gelatin sponge scaffold. However, the penetration profile and final concentrations of small molecule drugs achieved have not been determined to date. Here, we determined the extent of absorption of the clinical androgen receptor antagonist, enzalutamide, into prostate PDEs, using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and matrix-assisted laser/desorption ionisation (MALDI) mass spectrometry imaging (MSI). In a cohort of 11 PDE tissues from eight individual patients, LC-MS/MS quantification of PDE homogenates confirmed enzalutamide (10 µM) uptake by all PDEs, which reached maximal average tissue concentration of 0.24-0.50 ng/µg protein after 48 h culture. Time dependent uptake of enzalutamide (50 µM) in PDEs was visualized using MALDI MSI over 24-48 h, with complete penetration throughout tissues evident by 6 h of culture. Drug signal intensity was not homogeneous throughout the tissues but had areas of markedly high signal that corresponded to drug target (androgen receptor)-rich epithelial regions of tissue. In conclusion, application of MS-based drug quantification and visualization in PDEs, and potentially other 3-dimensional model systems, can provide a more robust basis for experimental study design and interpretation of pharmacodynamic data.
Assuntos
Absorção Fisico-Química , Antagonistas de Receptores de Andrógenos/química , Antineoplásicos/química , Avaliação Pré-Clínica de Medicamentos/métodos , Feniltioidantoína/análogos & derivados , Neoplasias da Próstata/patologia , Espectrometria de Massas em Tandem/métodos , Idoso , Benzamidas , Células Cultivadas , Cromatografia Líquida , Estudos de Coortes , Humanos , Masculino , Pessoa de Meia-Idade , Nitrilas , Feniltioidantoína/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
BACKGROUND: Nonalcoholic steatohepatitis (NASH) is common in the morbidly obese. It is a condition that can lead to progressive fibrosis and cirrhosis. We determined the prevalence in a population undergoing bariatric surgery and evaluated the possible serologic predictors before the development of fibrosis. METHODS: Liver biopsies were taken from 370 consecutive patients who were undergoing laparoscopic bariatric surgery. The clinical and biochemical parameters were then assessed for correlation with the histologic features of nonalcoholic steatohepatitis. RESULTS: Of the 370 patients, 68 (18%) were found to have NASH. Increased insulin resistance, alanine transaminase, and total bilirubin were independently associated with the presence of NASH. The presence of ≥ 2 of the 3 provided the best combination of sensitivity (.71) and specificity (.71) for predicting NASH. CONCLUSION: Increased insulin resistance, alanine transaminase, and total bilirubin are serologic predictors for the presence of NASH before the development of fibrosis.
Assuntos
Fígado Gorduroso/etiologia , Fígado/patologia , Obesidade Mórbida/complicações , Adulto , Alanina Transaminase/sangue , Cirurgia Bariátrica/métodos , Bilirrubina/sangue , Biomarcadores/sangue , Biópsia por Agulha , Fígado Gorduroso/diagnóstico , Feminino , Humanos , Resistência à Insulina/fisiologia , Laparoscopia/métodos , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Masculino , Obesidade Mórbida/cirurgia , Curva ROCRESUMO
Prostate cancer is the most common visceral cancer and the second most common cause of cancer death in males. The number of radical prostatectomies performed each year is increasing and accurate data from the histopathological examination of these specimens aid clinicians in stratifying patients for surveillance and adjuvant therapies. This review focuses on the histopathological prognostic factors which should be routinely recorded in pathology reports and complements the Royal College of Pathologists of Australasia Structured Reporting Protocol for Prostate Cancer (Radical Prostatectomy). Such structured pathology reports have been shown to significantly enhance the completeness and quality of data provided to clinicians. The review also discusses the International Society for Urological Pathology Consensus Conference recommendations which were published recently.
Assuntos
Adenocarcinoma/secundário , Neoplasias da Próstata/patologia , Adenocarcinoma/cirurgia , Humanos , Linfonodos/patologia , Metástase Linfática , Masculino , Invasividade Neoplásica , Prognóstico , Prostatectomia , Neoplasias da Próstata/cirurgia , Glândulas Seminais/patologiaRESUMO
ZNF652, a DNA binding transcription factor, was previously suggested to be differentially expressed in prostate cancer. This study investigated if the expressions of ZNF652 and androgen receptor (AR) in prostate cancer are associated with prostate specific antigen (PSA) defined relapse. ZNF652 and AR immunoreactivity were evaluated in prostate tissues from a cohort of 121 patients with prostate cancer and associations with disease outcome determined. To assess if ZNF652 can influence AR expression, or vice versa, levels of expression of ZNF652, AR and PSA were determined in the prostate cell line LNCaP following induction of AR activity by 5alpha-dihydrotestosterone, or knockdown of ZNF652 expression. Two thirds of prostate tumors retained high levels of ZNF652 (71/109 cases) and 50% of tumors high levels of AR (57/113). There was a significant decrease (p=0.005) in relapse-free survival of patients with high expression levels of both ZNF652 and AR and this was independent of preoperative PSA and seminal vesicle involvement. Modulation of either AR or ZNF652 expression levels in LNCaP cells was not associated with any corresponding changes to the levels of either ZNF652 or AR, respectively. High levels of expression of both AR and ZNF652 in clinically organ-defined prostate cancer are associated with a statistically increased risk of relapse. The ZNF652 and AR transcription factors are acting independently and it is proposed that the continued maintenance of expression of ZNF652 in AR positive cells results in a gene expression pattern that contributes to the relapse.
Assuntos
Biomarcadores Tumorais/análise , Proteínas de Ligação a DNA/biossíntese , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/biossíntese , Adulto , Idoso , Western Blotting , Proteínas de Ligação a DNA/genética , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Receptores Androgênicos/genética , Análise Serial de TecidosRESUMO
BACKGROUND: Previous studies from our laboratory demonstrated a strong association between an elevated level of chondroitin sulfate (CS) in peritumoral stroma and PSA-relapse in patients with early stage disease. In this study we determined whether CS levels could predict overall survival in men diagnosed with advanced prostate cancer subsequently treated by orchiectomy alone. METHODS: CS was localized in archived prostatic tissues by immunohistochemistry, and the level of CS expression as measured by video image analysis was compared in cohorts of 157 and 60 men with early stage or advanced disease, respectively. RESULTS: The CS levels in the peritumoral stroma of patients without relapse after treatment for early stage disease was significantly reduced compared to levels in prostate tissue from patients who either relapsed (P = 0.003) or were diagnosed with advanced prostate cancer (P < 0.00001). There was no difference between the median CS level in the peritumoral prostatic stroma of early stage patients that relapsed after treatment and patients diagnosed with advanced prostate cancer. Increased CS levels (P < 0.0001) and high Gleason score (P < 0.0001) were associated with an increased rate of PSA-relapse in the cohort of patients with early stage disease. However, neither CS level nor Gleason score alone or in combination could predict survival outcome in patients with advanced prostate cancer following androgen deprivation therapy. CONCLUSIONS: Although peritumoral CS levels and Gleason score are strong predictors of relapse-free survival in early stage prostate cancer patients, neither peritumoral CS levels nor Gleason score can predict survival outcome in patients with advanced disease.
Assuntos
Sulfatos de Condroitina/metabolismo , Neoplasias da Próstata/metabolismo , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Humanos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Orquiectomia , Valor Preditivo dos Testes , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Estudos RetrospectivosRESUMO
The glycosaminoglycan chondroitin sulfate is significantly increased in the peritumoral stroma of prostate tumors compared with normal stroma and is an independent predictor of prostate-specific antigen (PSA) relapse following radical prostatectomy. In this study, we determined whether specific alterations in the sulfation pattern of glycosaminoglycan chains in clinically organ-confined prostate cancer are associated with PSA relapse. Immunoreactivity to distinct glycosaminoglycan disaccharide epitopes was assessed by manually scoring the staining intensity in prostate tissues from patients with benign prostatic hyperplasia (n = 19), early-stage cancer (cohort 1, n = 55 and cohort 2, n = 275), and advanced-stage cancer (n = 20). Alterations to glycosaminoglycans in benign and malignant prostate tissues were determined by cellulose acetate chromatography and high-pressure liquid chromatography. Glycosaminoglycan disaccharide epitopes were localized to the peritumoral stroma of clinically localized prostate cancer. The level of immunostaining for unsulfated disaccharides (C0S) in the peritumoral stroma, but not for 4-sulfated (C4S) or 6-sulfated disaccharides (C6S), was significantly associated with the rate of PSA relapse following radical prostatectomy. High levels of C0S immunostaining were determined to be an independent predictor of PSA relapse (1.6-fold, P = 0.020). Advanced-stage prostate cancer tissues exhibited reduced electrophoretic mobility for chondroitin sulfate and increased unsulfated disaccharides when compared with benign prostatic hyperplasia tissues, whereas the sulfated disaccharide levels were unaffected. The level of C0S immunostaining in the peritumoral stroma is an independent determinant of PSA failure in clinically localized prostate cancer. Specific alterations to chondroitin sulfate side chains occurring during tumor development may be a crucial step for disease progression in prostate cancer.
Assuntos
Condroitina/metabolismo , Dissacarídeos/metabolismo , Neoplasias da Próstata/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Epitopos , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/patologiaRESUMO
BACKGROUND: In this study, we investigated the expression of HER-2/neu and AR in clinically organ-confined prostate cancer to determine whether alterations in these signaling pathways contribute to the development of metastatic disease. METHODS: HER-2/neu and AR immunoreactivity were evaluated in archived prostatic tissues obtained from 53 men with clinically organ-confined disease who underwent radical prostatectomy. Associations between AR and HER-2/neu immunostaining and disease outcome were determined. RESULTS: Seventy percent (37/53) of tumors exhibited high levels of HER-2/neu immunostaining and 68% (36/53) of tumors had elevated AR levels. Patients with high levels of both HER-2/neu and AR had the highest rate of PSA failure (56%, 15/27) compared with no PSA failures amongst seven patients with low levels of both HER-2/neu and AR (log rank statistic 7.69, P = 0.021). Concurrent high levels of HER-2/neu and AR expression were significantly associated with high pathological stage (P = 0.027) and development of metastatic disease (P = 0.022). CONCLUSIONS: These findings support the notion that both the HER-2/neu and AR signaling pathways may contribute to development of metastatic disease. The subset of prostate tumors with increased HER-2/neu and AR levels may benefit from treatment strategies that target both signaling pathways.
Assuntos
Neoplasias da Próstata/patologia , Receptor ErbB-2/análise , Receptores Androgênicos/análise , Idoso , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia/diagnóstico , Antígeno Prostático Específico/sangue , Prostatectomia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/cirurgia , Receptor ErbB-2/imunologia , Receptores Androgênicos/imunologiaRESUMO
Sequential reactions of trans-(C6F5)(p-tol3P)2Pt(C[triple chemical bond]C)3SiEt3 (PtC6SiEt3) with nBu4N+ F(-) (THF/methanol), PtCl, KPF6/tBuOK, and CuCl give trans,trans-[(C6F5){(p-tol3P)2}Pt(C[triple chemical bond]C)3Pt{(Pp-tol3)2}(C6F5)] (PtC6Pt) in 95 % yield on multigram scales. Reactions of PtC6Pt and Ar2P(CH2)mPAr2 afford substitution products trans,trans-[(C6F5){(Ar2P(CH2)mPAr2)}Pt(C[triple chemical bond]C)3Pt{(Ar2P(CH2)mPAr2)}(C6F5)] (PtC6Pt-m/Ar; m/Ar=8/p-tol, 78 %; 10/Ph, 82 %; 11/Ph, 69 %; 12/Ph, 57 %; 14/p-tol, 57 %; 14/p-C6H4-tBu, 71 %), in which the diphosphines span the square planar platinum endgroups. An analogous reaction with PEt3 gives a tetrakis PEt3 complex Pt'C6Pt' (72 %). The crystal structures of PtC6Pt, Pt'C6Pt', PtC6Pt-10/Ph, PtC6Pt-11/Ph, and PtC6Pt-14/p-tol or solvates thereof are compared. In PtC6Pt, the endgroups can avoid van der Waals contact, and define angles of 0 degrees . In PtC6Pt-14/p-tol, the sp3 chains twist around the sp chain in a chiral double-helical motif, with an endgroup/endgroup angle of 189 degrees . The sp3 chains are too short to adopt analogous conformations in the other complexes, but laterally shield the sp chain. NMR spectroscopy shows that the helical enantiomers of PtC6Pt-14/p-tol rapidly interconvert in solution at low temperature. A crystal structure of PtC4Pt shows endgroups that are in van der Waals contact and define an angle of 41 degrees . Reactions with Ar2P(CH2)8PAr2 give PtC4Pt-8/Ar (Ar=Ph, 53 %; p-tol, 87 %). Low-temperature NMR spectroscopy establish non-helical chiral conformations. Electrochemical oxidations of the diplatinum complexes are analyzed, the reversibilities of which decrease with increasing sp chain length.
RESUMO
Reactions of trans,trans-(C6F5)(p-tol3P)2Pt(CC)4Pt(Pp-tol3)2(C6F5) and diphosphines Ar2P(CH2)mPAr2 yield trans,trans-(C6F5)(Ar2P(CH2)mPAr2)Pt(CC)4Pt(Ar2P(CH2)mPAr2)(C6F5), in which the platinum atoms are spanned via an sp and two sp3 carbon chains (Ar/m = 3, Ph/14, 87%; 4, p-tol/14, 91%; 5, p-C6H4-t-Bu/14, 77%; 7, Ph/10, 80%; 8, Ph/11, 80%; 9, Ph/12, 36%; only oligomers form for m > 14). Crystal structures of 3-5 show that the sp3 chains adopt chiral double-helical conformations that shield the sp chain at approximately the van der Waals distance, with both enantiomers in the unit cell. The platinum square planes define angles of 196.6 degrees -189.9 degrees or more than a half twist. Crystal structures of 7-9, which have shorter sp3 chains, exhibit nonhelical conformations. Reaction of the corresponding Pt(CC)6Pt complex and Ph2P(CH2)18PPh2 gives an analogous adduct (27%). The crystal structure shows two independent molecules, one helical and the other not. Low-temperature NMR data suggest that the enantiomeric helical conformations of 3-5 rapidly interconvert in solution. Cyclic voltammograms of 3-5 show more reversible oxidations than model compounds lacking bridging sp3 chains. These are the only double-helical molecules that do not feature bonding interactions between the helix strands, or covalent bonds to templates dispersed throughout the strands, or any type of encoding. The driving force for helix formation is analyzed.
RESUMO
BACKGROUND AND PURPOSE: The accuracy of the dose monitor system of a medical electron accelerator is of crucial importance for the precise delivery of the prescribed dose. Special attention is given to the case of low monitor units (MU). The long-term stability of the dose monitor system is analyzed. MATERIAL AND METHODS: Photon and electron fields with monitor units between 1 and 500 MU were measured with field sizes of 10 x 10 cm(2) and 20 x 20 cm(2) at source-skin distances (SSDs) of 100 cm and 95 cm, respectively. The relative dose per MU [see text] was determined for an Elekta linear accelerator. RESULTS: The relative dose per MU was measured to be constant within about 1% down to fields with only 2 MU. The deviation remained below 2% down to 1 MU which is the minimum setting of the accelerator. The long-term stability is better than 0.2% per month. CONCLUSION: No therapeutically relevant deviation of the prescribed dose could be detected for the Elekta linear accelerator. This is a prerequisite for the implementation of intensity-modulated radiotherapy (IMRT) techniques.
Assuntos
Aceleradores de Partículas/instrumentação , Monitoramento de Radiação/instrumentação , Radioterapia Conformacional/instrumentação , Radioterapia de Intensidade Modulada/instrumentação , Carga Corporal (Radioterapia) , Elétrons , Desenho de Equipamento , Humanos , FótonsRESUMO
BACKGROUND: Although up to 30% of men who undergo radical prostatectomy for clinically organ-confined prostate cancer will relapse with disseminated disease, currently it is not possible to predict these patients. METHODS: Androgen receptor (AR) immunoreactivity in stromal and epithelial compartments of tumor foci was evaluated by video image analysis in 53 radical prostatectomy specimens. Kaplan-Meier and Cox Regression analyses were used to determine whether AR immunostaining was related to rate and risk of relapse, respectively. RESULTS: Ninety-eight percent (52/53) of the tumors contained AR positive malignant epithelial cells. Kaplan-Meier analysis indicated that patients with high AR levels (>64% AR positive nuclear area) in the malignant epithelial cells or low AR levels (Assuntos
Próstata/metabolismo
, Próstata/patologia
, Neoplasias da Próstata/metabolismo
, Neoplasias da Próstata/patologia
, Receptores Androgênicos/metabolismo
, Idoso
, Biomarcadores Tumorais/metabolismo
, Núcleo Celular/patologia
, Intervalo Livre de Doença
, Células Epiteliais/metabolismo
, Células Epiteliais/patologia
, Humanos
, Masculino
, Pessoa de Meia-Idade
, Valor Preditivo dos Testes
, Modelos de Riscos Proporcionais
, Neoplasias da Próstata/mortalidade
, Recidiva
, Células Estromais/metabolismo
, Células Estromais/patologia
RESUMO
The reaction of trans-[(C(6)F(5))(p-tol(3)P)(2)PtCl] (PtCl) and butadiyne (cat. CuI, HNEt(2)) gives trans-[(C(6)F(5))(p-tol(3)P)(2)Pt(Ctbond;C)(2)H] (PtC(4)H, 81 %), which reacts with excess HC(triple bond)CSiEt(3) under Hay coupling conditions (O(2), cat. CuCl/TMEDA, acetone) to yield PtC(6)Si (53 %). A solution of PtC(6)Si in acetone is treated with wet nBu(4)NF to generate PtC(6)H. The addition of ClSiMe(3) (F(-) scavenger) and then excess HC(triple bond)CSiEt(3) under Hay conditions gives PtC(8)Si (39 %). Hay homocouplings of PtC(4)H, PtC(6)H, and PtC(8)H (generated in situ analogously to PtC(6)H) yield PtC(8)Pt, PtC(12)Pt, and PtC(16)Pt (97-92 %). Reactions of PtC(4)H and PtC(6)H with PtCl (cat. CuCl, HNEt(2)) give PtC(4)Pt and PtC(6)Pt (69 %, 34 %). The attempted conversion of PtC(8)H to PtC(10)Si affords mainly PtC(16)Pt, with traces of PtC(20)Pt and PtC(24)Pt. The complexes PtC(x)Pt are exceedingly stable (dec pts 234 to 288 degrees C), and Et(3)P displaces p-tol(3)P to give the corresponding compounds Pt'C(8)Pt' and Pt'C(12)Pt' (94-90 %). The effect of carbon chain lengths upon IR nu(C(triple bond)C) patterns (progressively more bands), UV/Vis spectra (progressively red-shifted and more intense bands with epsilon >600 000 M(-1) cm(-1)), redox properties (progressively more difficult and less reversible oxidations), and NMR values are studied, and analyzed with respect to the polymeric sp carbon allotrope "carbyne". The crystal structure of PtC(12)Pt shows a dramatic, unprecedented degree of chain bending, whereas the chains in PtC(8)Pt, Pt'C(12)Pt', and PtC(16)Pt are nearly linear.
RESUMO
The authors report a 16 year old girl with a supratentorial rhabdoid glioblastoma. The radiological features, histopathology and management of this rare variant of glioblastoma multiforme are discussed.
Assuntos
Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Glioblastoma/cirurgia , Tumor Rabdoide/patologia , Tumor Rabdoide/cirurgia , Adolescente , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Evolução Fatal , Feminino , Glioblastoma/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Tumor Rabdoide/diagnóstico por imagem , Tomografia Computadorizada por Raios XRESUMO
Vascular endothelial growth factor (VEGF) is a peptide growth factor specific for the tyrosine kinase receptors VEGF receptor-1 and -2 (VEGFR-1 and R-2). Whereas VEGF has well-defined actions on the vasculature, including the stimulation of endothelial cell growth and motility and blood vessel permeability, the function of the VEGF/receptor pathway in other cell types is largely unknown. Recently, VEGFR-1 and R-2 expression has been reported in prostate tumor cells. In this study, we demonstrate that these receptors colocalize with VEGF in prostate tumor cells, prostatic intraepithelial neoplasia, and the basal cells of normal glands. Furthermore, in comparison with normal glands, the expression of VEGFR-1 and R-2 is increased in prostatic intraepithelial neoplasia and malignant cells in well and moderately differentiated prostate cancer but is decreased in poorly differentiated cancer. Culture of the prostate cancer cell line LNCaP in the presence of recombinant human VEGF165 resulted in a 50% increase in [(3)H]thymidine uptake by these cells and recruitment of quiescent cells into the cell cycle. This effect of recombinant human VEGF165 was abolished by neutralizing antisera to VEGFR-2. These data suggest that VEGF may not only mediate neovascularization associated with prostate cancer progression but may also directly stimulate prostate tumor cells via VEGFR-2-dependent autocrine and/or paracrine mechanisms.