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1.
Clin Genitourin Cancer ; 22(3): 102098, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38733897

RESUMO

BACKGROUND: To evaluate relationship between histological subtypes of renal cell carcinoma (RCC) and preoperative c-reactive protein (CRP). PATIENTS AND METHODS: We queried the International Marker Consortium for Renal Cancer database for patients affected by RCC. Patients were classified according to their histology: benign tumors, clear cell (cc) RCC, chromophobe (ch) RCC, papillary (p) RCC, and variant histology (vh) RCC; and according to CRP (mg/L): low CRP ≤5 and high CRP >5. Primary outcome was all-cause mortality (ACM). Secondary outcomes were cancer-specific mortality (CSM), recurrence and association between CRP and histology. Multivariable analysis (MVA) via Cox regression and multivariable logistic regression were fitted to elucidate predictors of outcomes. RESULTS: Total 3902 patients (high CRP n = 1266) were analyzed; median follow up 51 (IQR 20-91) months. On MVA elevated CRP was an independent risk factor associated with increased risk of ACM in benign tumors (HR 5.98, P < .001), ccRCC (HR 2.69, P < .001), chRCC (HR 3.99, P < .001), pRCC (HR 1.76, P = .009) and vhRCC (HR 2.97, P =.007). MVA for CSM showed CRP as risk factor in ccRCC (HR 2.77, P < .001), chRCC (HR 6.16, P = .003) and pRCC (HR 2.29, P = .011), while in vhRCC was not (P = .27). MVA for recurrence reported CRP as risk factor for ccRCC (HR 1.30, P = .013), while in chRCC (P = .33), pRCC (P = .34) and vhRCC (P = .52) was not. On multivariable logistic regression CRP was a predictor of pRCC (OR 1.003, P = .002), while decreasing CRP was associated with benign tumors (OR 0.994, P = .048). CONCLUSION: Elevated CRP was a robust predictor of worsened ACM in all renal cortical neoplasms. While most frequently observed in pRCC patients, elevated CRP was independently associated with worsened CSM in non-vhRCC. Conversely, elevated CRP was least likely to be noted in benign tumors, and elevation in this subgroup of patients should prompt further consideration for surveillance given increased risk of ACM. Further investigation is requisite.

2.
Biomolecules ; 13(10)2023 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-37892204

RESUMO

Human complement receptor 1 (CR1) is a membrane-bound regulator of complement that has been the subject of recent attempts to generate soluble therapeutic compounds comprising different fragments of its extracellular domain. This review will focus on the extracellular domain of CR1 and detail how its highly duplicated domains work both separately and together to mediate binding to its main ligands C3b and C4b, and to inhibit the classical, lectin, and alternative pathways of the complement cascade via the mechanisms of decay acceleration activity (DAA) and co-factor activity (CFA). Understanding the molecular basis of CR1 activity is made more complicated by the presence not only of multiple ligand binding domains within CR1 but also the fact that C3b and C4b can interact with CR1 as both monomers, dimers, and heterodimers. Evidence for the interaction of CR1 with additional ligands such as C1q will also be reviewed. Finally, we will bring the mechanistic understanding of CR1 activity together to provide an explanation for the differential complement pathway inhibition recently observed with CSL040, a soluble CR1-based therapeutic candidate in pre-clinical development.


Assuntos
Ativação do Complemento , Receptores de Complemento 3b , Humanos , Proteínas do Sistema Complemento , Receptores de Complemento 3b/metabolismo
3.
SN Compr Clin Med ; 4(1): 96, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35434525

RESUMO

Myositis ossificans circumscripta (MOC) is a benign disease characterized by localized heterotopic bone formation within muscles or soft tissue, usually interesting great muscles of extremities. We report a rare case of unusual location in the neck not associated with previous trauma, mimicking a solid tumor, with well-documented diagnostic imaging features. During COVID-19 pandemic outbreak in Italy, in May 2020, a 14-year-old boy developed a progressive and persistent neck pain on the right side, without known history of trauma. Initial therapy with non-steroid anti-inflammatory drugs and physiokinetic therapy gave only a slight improvement. A neck ultrasound showed an inhomogeneous right neck mass, with posterior shadowing due to calcifications. Computed tomography and magnetic resonance imaging confirmed a huge right neck mass, located in the paravertebral space with peripheral calcifications and mild central contrast enhancement. After surgical excision of the lesion, pathology revealed the presence of muscular tissue mixed with fibroblastic/myofibroblastic proliferation and ossification areas consistent with myositis ossificans. A careful analysis of clinical and radiological features is very important to manage young patients showing progressive pain and swelling of the neck, since MOC can mimic soft tissue or bone tumors, and it should be suspected even in the absence of a known history of trauma.

4.
J Med Imaging Radiat Oncol ; 66(3): 414-418, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34169667

RESUMO

Pseudoprogression (PP) is a diagnostic dilemma in the follow-up of brain high grade gliomas (HGG), and the introduction of new therapies has further complicated its identification in Magnetic Resonance Imaging (MRI). We report a case of pseudoprogression after intraoperative radiotherapy (ioRT) and Regorafenib therapy in a patient with anaplastic astrocytoma recurrence. A 65-year-old man, treated in August 2017 for a right frontal anaplastic astrocytoma, with surgical resection and following radiotherapy and Temozolomide, in October 2019 was again treated for peri-surgical bed recurrence with resection and ioRT followed by Regorafenib therapy, interrupted in February 2020, after the onset of adverse reactions. MRI examination showed a large irregular alteration posterior to the surgical bed, T2 weighted hypointense featuring strong diffusion restriction (low ADC values), with an irregular contrast-enhancement (CE) pattern, and surrounded by a vast vasogenic oedema; Dynamic Susceptibility Contrast (DSC) perfusion imaging (PWI) showed no increase of relative cerebral blood volume (rCBV). Particularly, lesion appeared markedly hypointense and dusty-like on susceptibility weighted images (SWI) probably due to a constant hemorrhagic diapedesis promoted by Regorafenib. Therefore, pseudoprogression was suspected. Follow-up MRI exams showed gradual reduction of SWI and CE abnormalities, but a persistent DWI restriction. Unfortunately, the last MRI control showed a secondary cerebellar localisation of the disease. New therapies are changing MRI pattern in HGG imaging and this case underlines how a multimodality approach is increasingly necessary. In particular, when using anti-VEGF drugs, SWI can have a crucial role in identifying therapy-related haemorrhagic changes.


Assuntos
Neoplasias Encefálicas , Glioma , Idoso , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Glioma/diagnóstico por imagem , Glioma/tratamento farmacológico , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Compostos de Fenilureia/uso terapêutico , Piridinas/uso terapêutico
5.
J Med Imaging Radiat Oncol ; 64(4): 534-536, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32037676

RESUMO

Anorexia nervosa is a psychiatric eating disorder related to malnutrition and consequent altered metabolism. A 48-year-old female with a history of anorexia in the last 2 years referred to our hospital with spinal pain. She underwent spinal X-ray and magnetic resonance imaging (MRI) showing multiple vertebral collapses in dorsal and lumbar spine with inversion of normal bone marrow and soft tissue signal in T1-weighted and STIR images. We describe this case of spinal 'flip-flop' phenomenon, underlining how what seems a technical failure is actually a specific imaging pattern related to the clinical context.


Assuntos
Anorexia Nervosa/patologia , Medula Óssea/diagnóstico por imagem , Medula Óssea/patologia , Imageamento por Ressonância Magnética/métodos , Radiografia/métodos , Coluna Vertebral/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Coluna Vertebral/diagnóstico por imagem
7.
Nat Commun ; 8(1): 606, 2017 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-28928458

RESUMO

The presence of tumor-infiltrating lymphocytes in triple-negative breast cancers is correlated with improved outcomes. Ras/MAPK pathway activation is associated with significantly lower levels of tumor-infiltrating lymphocytes in triple-negative breast cancers and while MEK inhibition can promote recruitment of tumor-infiltrating lymphocytes to the tumor, here we show that MEK inhibition adversely affects early onset T-cell effector function. We show that α-4-1BB and α-OX-40 T-cell agonist antibodies can rescue the adverse effects of MEK inhibition on T cells in both mouse and human T cells, which results in augmented anti-tumor effects in vivo. This effect is dependent upon increased downstream p38/JNK pathway activation. Taken together, our data suggest that although Ras/MAPK pathway inhibition can increase tumor immunogenicity, the negative impact on T-cell activity is functionally important. This undesirable impact is effectively prevented by combination with T-cell immune agonist immunotherapies resulting in superior therapeutic efficacy.MEK inhibition in breast cancer is associated with increased tumour infiltrating lymphocytes (TILs), however, MAPK activity is required for T cells function. Here the authors show that TILs activity following MEK inhibition can be enhanced by agonist immunotherapy resulting in synergic therapeutic effects.


Assuntos
Ligante 4-1BB/agonistas , Proliferação de Células/efeitos dos fármacos , Imunoterapia , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Neoplasias Mamárias Animais/imunologia , Ligante OX40/agonistas , Inibidores de Proteínas Quinases/farmacologia , Piridonas/farmacologia , Pirimidinonas/farmacologia , Subpopulações de Linfócitos T/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/imunologia , Animais , Neoplasias da Mama/imunologia , Linhagem Celular Tumoral , Feminino , Humanos , Linfócitos do Interstício Tumoral/imunologia , MAP Quinase Quinase 1/antagonistas & inibidores , MAP Quinase Quinase 2/antagonistas & inibidores , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/imunologia , Camundongos , Linfócitos T/efeitos dos fármacos
8.
J Neurol Phys Ther ; 41(3): 164-172, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28628550

RESUMO

BACKGROUND AND PURPOSE: Spontaneous visual recovery is rare after cortical blindness. While visual rehabilitation may improve performance, no visual therapy has been widely adopted, as clinical outcomes are variable and rarely translate into improvements in activities of daily living (ADLs). We explored the potential value of a novel rehabilitation approach "cognitive therapeutic exercises" for cortical blindness. CASE DESCRIPTION: The subject of this case study was 48-year-old woman with cortical blindness and tetraplegia after cardiac arrest. Prior to the intervention, she was dependent in ADLs and poorly distinguished shapes and colors after 19 months of standard visual and motor rehabilitation. Computed tomographic images soon after symptom onset demonstrated acute infarcts in both occipital cortices. INTERVENTION: The subject underwent 8 months of intensive rehabilitation with "cognitive therapeutic exercises" consisting of discrimination exercises correlating sensory and visual information. OUTCOMES: Visual fields increased; object recognition improved; it became possible to watch television; voluntary arm movements improved in accuracy and smoothness; walking improved; and ADL independence and self-reliance increased. Subtraction of neuroimaging acquired before and after rehabilitation showed that focal glucose metabolism increases bilaterally in the occipital poles. DISCUSSION: This study demonstrates feasibility of "cognitive therapeutic exercises" in an individual with cortical blindness, who experienced impressive visual and sensorimotor recovery, with marked ADL improvement, more than 2 years after ischemic cortical damage.Video Abstract available for additional insights from the authors (see Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A173).


Assuntos
Cegueira Cortical/psicologia , Cegueira Cortical/reabilitação , Terapia Cognitivo-Comportamental , Terapia por Exercício , Atividades Cotidianas , Cegueira Cortical/fisiopatologia , Feminino , Humanos , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Visão Ocular , Caminhada
9.
Sci Transl Med ; 9(393)2017 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-28592566

RESUMO

Immune checkpoint inhibitors have emerged as a potent new class of anticancer therapy. They have changed the treatment landscape for a range of tumors, particularly those with a high mutational load. To date, however, modest results have been observed in breast cancer, where tumors are rarely hypermutated. Because BRCA1-associated tumors frequently exhibit a triple-negative phenotype with extensive lymphocyte infiltration, we explored their mutational load, immune profile, and response to checkpoint inhibition in a Brca1-deficient tumor model. BRCA1-mutated triple-negative breast cancers (TNBCs) exhibited an increased somatic mutational load and greater numbers of tumor-infiltrating lymphocytes, with increased expression of immunomodulatory genes including PDCD1 (PD-1) and CTLA4, when compared to TNBCs from BRCA1-wild-type patients. Cisplatin treatment combined with dual anti-programmed death-1 and anti-cytotoxic T lymphocyte-associated antigen 4 therapy substantially augmented antitumor immunity in Brca1-deficient mice, resulting in an avid systemic and intratumoral immune response. This response involved enhanced dendritic cell activation, reduced suppressive FOXP3+ regulatory T cells, and concomitant increase in the activation of tumor-infiltrating cytotoxic CD8+ and CD4+ T cells, characterized by the induction of polyfunctional cytokine-producing T cells. Dual (but not single) checkpoint blockade together with cisplatin profoundly attenuated the growth of Brca1-deficient tumors in vivo and improved survival. These findings provide a rationale for clinical studies of combined immune checkpoint blockade in BRCA1-associated TNBC.


Assuntos
Proteína BRCA1/genética , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Mutação/genética , Proteínas Supressoras de Tumor/genética , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno B7-H1/metabolismo , Neoplasias da Mama/tratamento farmacológico , Proliferação de Células , Feminino , Humanos , Linfócitos do Interstício Tumoral/imunologia , Camundongos , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/imunologia
10.
Curr Treat Options Oncol ; 18(6): 35, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28534250

RESUMO

OPINION STATEMENT: Despite many advances in the treatment of breast cancer, the development of metastatic disease remains an incurable and frequent cause of cancer death for women worldwide. An improved understanding of the role of host immunosurveillance in modulating breast cancer disease biology, as well as impressive survival benefits seen to checkpoint blockade in other malignancies have provided great hope for an expanding role of immunotherapies in breast cancer management. While these novel therapies are currently being investigated in clinical trials, signals of efficacy, and tolerability in early phase studies suggest these will eventually make their way into standard practice algorithms. Ongoing research has highlighted a high degree of intertumoural heterogeneity in tumour lymphocytic infiltrates, suggesting some tumours or subtypes are more immunogenic than others. Furthermore, tumour intrinsic mechanisms of immune evasion are beginning to be uncovered, potentially representing key therapeutic targets to use in combination with checkpoint blockade, exemplifying the emerging concept of personalised medicine approaches to immune therapies. Subsequently, different immunotherapeutic strategies may be required based on stratification by these factors-for the minority of tumours with a high level of pre-existing immunity, immune checkpoint blockade monotherapy may be sufficient. However, for the majority of tumours with lower levels of pre-existing immunity, combination approaches will likely be required to achieve maximal therapeutic effect. Results of ongoing clinical trials including combinations with chemotherapy, radiation therapy, and targeted therapies are eagerly awaited.


Assuntos
Neoplasias da Mama/imunologia , Neoplasias da Mama/terapia , Imunoterapia , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/metabolismo , Ensaios Clínicos como Assunto , Gerenciamento Clínico , Feminino , Humanos , Vigilância Imunológica , Imunomodulação/efeitos dos fármacos , Imunoterapia/efeitos adversos , Imunoterapia/métodos , Subpopulações de Linfócitos/efeitos dos fármacos , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/metabolismo , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Terapia de Alvo Molecular , Metástase Neoplásica , Estadiamento de Neoplasias , Seleção de Pacientes , Prognóstico , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
12.
PLoS Med ; 13(12): e1002204, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28027312

RESUMO

BACKGROUND: Understanding the cancer genome is seen as a key step in improving outcomes for cancer patients. Genomic assays are emerging as a possible avenue to personalised medicine in breast cancer. However, evolution of the cancer genome during the natural history of breast cancer is largely unknown, as is the profile of disease at death. We sought to study in detail these aspects of advanced breast cancers that have resulted in lethal disease. METHODS AND FINDINGS: Three patients with oestrogen-receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer and one patient with triple negative breast cancer underwent rapid autopsy as part of an institutional prospective community-based rapid autopsy program (CASCADE). Cases represented a range of management problems in breast cancer, including late relapse after early stage disease, de novo metastatic disease, discordant disease response, and disease refractory to treatment. Between 5 and 12 metastatic sites were collected at autopsy together with available primary tumours and longitudinal metastatic biopsies taken during life. Samples underwent paired tumour-normal whole exome sequencing and single nucleotide polymorphism (SNP) arrays. Subclonal architectures were inferred by jointly analysing all samples from each patient. Mutations were validated using high depth amplicon sequencing. Between cases, there were significant differences in mutational burden, driver mutations, mutational processes, and copy number variation. Within each case, we found dramatic heterogeneity in subclonal structure from primary to metastatic disease and between metastatic sites, such that no single lesion captured the breadth of disease. Metastatic cross-seeding was found in each case, and treatment drove subclonal diversification. Subclones displayed parallel evolution of treatment resistance in some cases and apparent augmentation of key oncogenic drivers as an alternative resistance mechanism. We also observed the role of mutational processes in subclonal evolution. Limitations of this study include the potential for bias introduced by joint analysis of formalin-fixed archival specimens with fresh specimens and the difficulties in resolving subclones with whole exome sequencing. Other alterations that could define subclones such as structural variants or epigenetic modifications were not assessed. CONCLUSIONS: This study highlights various mechanisms that shape the genome of metastatic breast cancer and the value of studying advanced disease in detail. Treatment drives significant genomic heterogeneity in breast cancers which has implications for disease monitoring and treatment selection in the personalised medicine paradigm.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Exoma , Mutação , Polimorfismo de Nucleotídeo Único , Adulto , Autopsia , Pesquisa Participativa Baseada na Comunidade , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos
13.
Cancer Res ; 76(14): 4236-48, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27231202

RESUMO

Metastatic disease is the major cause of breast cancer-related death and despite many advances, current therapies are rarely curative. Tumor cell migration and invasion require actin cytoskeletal reorganization to endow cells with capacity to disseminate and initiate the formation of secondary tumors. However, it is still unclear how these migratory cells colonize distant tissues to form macrometastases. The E6-associated protein, E6AP, acts both as an E3 ubiquitin-protein ligase and as a coactivator of steroid hormone receptors. We report that E6AP suppresses breast cancer invasiveness, colonization, and metastasis in mice, and in breast cancer patients, loss of E6AP associates with poor prognosis, particularly for basal breast cancer. E6AP regulates actin cytoskeletal remodeling via regulation of Rho GTPases, acting as a negative regulator of ECT2, a GEF required for activation of Rho GTPases. E6AP promotes ubiquitination and proteasomal degradation of ECT2 for which high expression predicts poor prognosis in breast cancer patients. We conclude that E6AP suppresses breast cancer metastasis by regulating actin cytoskeleton remodeling through the control of ECT2 and Rho GTPase activity. These findings establish E6AP as a novel suppressor of metastasis and provide a compelling rationale for inhibition of ECT2 as a therapeutic approach for patients with metastatic breast cancer. Cancer Res; 76(14); 4236-48. ©2016 AACR.


Assuntos
Neoplasias da Mama/patologia , Proteínas Proto-Oncogênicas/fisiologia , Transdução de Sinais/fisiologia , Ubiquitina-Proteína Ligases/fisiologia , Proteínas rho de Ligação ao GTP/fisiologia , Animais , Linhagem Celular Tumoral , Movimento Celular , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Invasividade Neoplásica , Metástase Neoplásica , Ubiquitina-Proteína Ligases/análise
14.
J Cell Sci ; 129(2): 277-89, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26644181

RESUMO

Eph receptors and their corresponding membrane-bound ephrin ligands regulate cell positioning and establish tissue patterns during embryonic and oncogenic development. Emerging evidence suggests that assembly of polymeric Eph signalling clusters relies on cytoskeletal reorganisation and underlies regulation by protein tyrosine phosphatases (PTPs). PTP-PEST (also known as PTPN12) is a central regulator of actin cytoskeletal dynamics. Here, we demonstrate that an N-terminal fragment of PTP-PEST, generated through an ephrinA5-triggered and spatially confined cleavage mediated by caspase-3, attenuates EphA3 receptor activation and its internalisation. Isolation of EphA3 receptor signalling clusters within intact plasma membrane fragments obtained by detergent-free cell fractionation reveals that stimulation of cells with ephrin triggers effective recruitment of this catalytically active truncated form of PTP-PEST together with key cytoskeletal and focal adhesion proteins. Importantly, modulation of actin polymerisation using pharmacological and dominant-negative approaches affects EphA3 phosphorylation in a similar manner to overexpression of PTP-PEST. We conclude that PTP-PEST regulates EphA3 activation both by affecting cytoskeletal remodelling and through its direct action as a PTP controlling EphA3 phosphorylation, indicating its multifaceted regulation of Eph signalling.


Assuntos
Efrina-A5/fisiologia , Proteína Tirosina Fosfatase não Receptora Tipo 12/fisiologia , Receptores Proteína Tirosina Quinases/metabolismo , Animais , Células COS , Caspase 3/metabolismo , Membrana Celular/metabolismo , Chlorocebus aethiops , Citoesqueleto/metabolismo , Células HEK293 , Humanos , Fosforilação , Ligação Proteica , Processamento de Proteína Pós-Traducional , Transporte Proteico , Receptor EphA3
15.
BMC Med ; 13: 202, 2015 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-26300242

RESUMO

While breast cancer has not been considered a cancer amenable to immunotherapeutic approaches, recent studies have demonstrated evidence of significant immune cell infiltration via tumor-infiltrating lymphocytes in a subset of patient tumors. In this review we present the current evidence highlighting the clinical relevance and utility of tumor-infiltrating lymphocytes in breast cancer. Retrospective and prospective studies have shown that the presence of tumor-infiltrating lymphocytes is a prognostic marker for higher responses to neoadjuvant chemotherapy and better survival, particularly in triple negative and HER2-positive early breast cancer. Further work is required to determine the immune subsets important in this response and to discover ways of encouraging immune infiltrate in tumor-infiltrating lymphocytes-negative patients.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Linfócitos do Interstício Tumoral/metabolismo , Antineoplásicos/uso terapêutico , Neoplasias da Mama/patologia , Feminino , Humanos , Terapia Neoadjuvante , Estudos Prospectivos , Estudos Retrospectivos
16.
Virology ; 417(2): 443-8, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21791360

RESUMO

HPV16 E6 deregulates G1/S cell cycle progression through p53 degradation preventing transcription of the CDK inhibitor p21(WAF1). However, additional mechanisms independent of p53 inactivation appear to exist. Here, we report that HPV16 E6 targets the cellular factor p150(Sal2), which positively regulates p21(WAF1) transcription. HPV16 E6 associates with p150(Sal2), inducing its functional inhibition by preventing its binding to cis elements on the p21(WAF1) promoter. A HPV16 E6 mutant, L110Q, which was unable to bind p150(Sal2), did not affect the ability of the cellular protein to bind p21(WAF1) promoter, underlining the linkage between these events. These data describe a novel mechanism by which HPV16 E6 induces cell cycle deregulation with a p53-independent pathway. The viral oncoprotein targets p150(Sal2), a positive transcription regulator of p21(WAF1) gene, preventing G1/S arrest and allowing cellular proliferation and efficient viral DNA replication.


Assuntos
Inibidor de Quinase Dependente de Ciclina p21/antagonistas & inibidores , Interações Hospedeiro-Patógeno , Proteínas Oncogênicas Virais/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Transcrição Gênica , Substituição de Aminoácidos/genética , Ciclo Celular , Linhagem Celular , Proteínas de Ligação a DNA , Humanos , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Mutação de Sentido Incorreto , Proteínas Oncogênicas Virais/genética , Proteínas Repressoras/genética
17.
Blood ; 112(3): 721-32, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18385452

RESUMO

Signaling by Eph receptors and cell-surface ephrin ligands modulates adhesive cell properties and thereby coordinates cell movement and positioning in normal and oncogenic development. While cell contact-dependent Eph activation frequently leads to cell-cell repulsion, also the diametrically opposite response, cell-cell adhesion, is a probable outcome. However, the molecular principles regulating such disparate functions have remained controversial. We have examined cell-biologic mechanisms underlying this switch by analyzing ephrin-A5-induced cell-morphologic changes of EphA3-positive LK63 pre-B acute lymphoblastic leukemia cells. Their exposure to ephrin-A5 surfaces leads to a rapid conversion from a suspended/nonpolarized to an adherent/polarized cell type, a transition that relies on EphA3 functions operating in the absence of Eph-kinase signaling. Cell morphology change and adhesion of LK63 cells are effectively attenuated by endogenous protein tyrosine phosphatase (PTP) activity, whereby PTP inhibition and productive EphA3-phosphotyrosine signaling reverse the phenotype to nonadherent cells with a condensed cytoskeleton. Our findings suggest that Eph-associated PTP activities not only control receptor phosphorylation levels, but as a result switch the response to ephrin contact from repulsion to adhesion, which may play a role in the pathology of hematopoietic tumors.


Assuntos
Adesão Celular , Efrinas/fisiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Proteínas Tirosina Fosfatases/metabolismo , Receptores da Família Eph/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Polaridade Celular , Forma Celular , Efrina-A5/fisiologia , Humanos , Fosforilação , Receptor EphA3/fisiologia , Transdução de Sinais
18.
Virology ; 367(1): 1-9, 2007 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-17568647

RESUMO

Epidemiological studies have demonstrated that 15 different mucosal human papillomavirus (HPV) types of the genus alpha of the HPV phylogetic tree are classified as high risk for cervical cancer development. Three additional HPV types of the same genus, HPV26, 53 and 66, are classified as probable high-risk types. In this study, we have characterized the biological properties of the E7 oncoproteins from these three HPV types. All of the corresponding E7 proteins were able to associate with retinoblastoma protein (pRb) and up-regulated the expression of several positive cell cycle regulators, i.e. CDK2, cyclin A and cylin E. However, HPV26 E7 appears to be more efficient than HPV53 and 66 E7 in up-regulating the transcription of cyclin A. Unlike E7 from the high-risk type HPV16 protein, HPV26, 53 and 66 did not efficiently promote pRb degradation. In addition, E7 from these viruses was able to promote proliferation of primary human keratinocytes and circumvent G1 arrest imposed by overexpression of p16(INK4a), but with less efficiency than the high-risk HPV16 E7. Together, our data show that in vitro properties of these E7 proteins correlate with the epidemiological classification of HPV26, 53 and 66 as HPV types with an intermediate risk for cervical cancer development.


Assuntos
Alphapapillomavirus/classificação , Alphapapillomavirus/patogenicidade , Transformação Celular Neoplásica , Queratinócitos/virologia , Proteínas E7 de Papillomavirus/metabolismo , Alphapapillomavirus/metabolismo , Linhagem Celular , Linhagem Celular Transformada , Células Cultivadas , Ciclina A/efeitos dos fármacos , Ciclina A/metabolismo , Ciclina E/efeitos dos fármacos , Ciclina E/metabolismo , Quinase 2 Dependente de Ciclina/efeitos dos fármacos , Quinase 2 Dependente de Ciclina/metabolismo , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Fase G1/efeitos dos fármacos , Humanos , Queratinócitos/metabolismo , Queratinócitos/patologia , Proteínas E7 de Papillomavirus/genética , Proteínas E7 de Papillomavirus/farmacologia , Infecções por Papillomavirus/virologia , Proteína do Retinoblastoma/metabolismo , Fatores de Risco , Regulação para Cima , Neoplasias do Colo do Útero/virologia
19.
J Immunol ; 178(5): 3186-97, 2007 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17312167

RESUMO

Cervical cancer development is linked to the persistent infection by high-risk mucosal human papillomaviruses (HPVs) types. The E6 and E7 major oncoproteins from this dsDNA virus play a key role in the deregulation of the cell cycle, apoptosis, and adaptive immune surveillance. In this study, we show for the first time that HPV type 16 (HPV16), the most carcinogenic type among the high-risk subgroup, interferes with innate immunity by affecting the expression of TLRs. Infection of human primary keratinocytes with HPV16 E6 and E7 recombinant retroviruses inhibits TLR9 transcription and hence functional loss of TLR9-regulated pathways. Similar findings were achieved in HPV16-positive cancer-derived cell lines and primary cervical cancers, demonstrating that this event occurs also in an in vivo context. Interestingly, E6 and E7 from the low-risk HPV type 6 are unable to down-regulate the TLR9 promoter. In addition, E6 and E7 from the high-risk HPV type 18, which are known to persist less competently in the host than HPV16, have reduced efficiency compared with HPV16 in inhibiting TLR9 transcription. Furthermore, a CpG motif derived from the HPV16 E6 DNA sequence activated TLR9, indicating this virus is able to initiate innate responses via the receptor it later down-regulates. This study reveals a novel mechanism used by HPV16 to suppress the host immune response by deregulating the TLR9 transcript, providing evidence that abolishing innate responses may be a crucial step involved in the carcinogenic events mediated by HPVs.


Assuntos
Transformação Celular Neoplásica/imunologia , Papillomavirus Humano 16/imunologia , Proteínas Oncogênicas Virais/imunologia , Infecções por Papillomavirus/imunologia , Proteínas Repressoras/imunologia , Receptor Toll-Like 9/imunologia , Neoplasias do Colo do Útero/imunologia , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Regulação para Baixo/imunologia , Feminino , Células HeLa , Papillomavirus Humano 16/metabolismo , Papillomavirus Humano 18/imunologia , Papillomavirus Humano 18/metabolismo , Humanos , Imunidade Inata , Proteínas Oncogênicas Virais/metabolismo , Proteínas E7 de Papillomavirus , Infecções por Papillomavirus/metabolismo , Infecções por Papillomavirus/patologia , Proteínas Repressoras/metabolismo , Receptor Toll-Like 9/biossíntese , Transcrição Gênica/imunologia , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia
20.
Cancer Lett ; 246(1-2): 274-81, 2007 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-16650526

RESUMO

Human Papillomavirus type 77 is a skin type found in non-melanoma skin cancers of immuno-compromised individuals. Although, the HPV77 E6 oncoprotein has been well studied, nothing is known about E7. Studies on mucosal HPV types (e.g. HPV16) showed that E7 deregulates the cell cycle by binding to and promoting degradation of retinoblastoma protein (pRb). Here, we characterized the impact of HPV77 E7 on the cell cycle. We observed that HPV77 E7 associated with pRb with a lower affinity than HPV16 E7, promoting weakly its degradation. Although, HPV16 E7 led to cellular proliferation and accumulation of the cell cycle inhibitor p16(INK4a), both events were not clearly observed in HPV77 E7 cells. Together, these data indicate that HPV77 E7 does not efficiently deregulate the cell cycle, in contrast to several E7s of mucosal HPV types.


Assuntos
Ciclo Celular/fisiologia , Proteínas E7 de Papillomavirus/metabolismo , Animais , Ciclo Celular/genética , Células Cultivadas , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Expressão Gênica , Vetores Genéticos/genética , Humanos , Immunoblotting , Camundongos , Células NIH 3T3 , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Proteínas E7 de Papillomavirus/genética , Ligação Proteica , Proteína do Retinoblastoma/genética , Proteína do Retinoblastoma/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
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