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1.
J Natl Compr Canc Netw ; 22(1): 4-16, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38394781

RESUMO

The NCCN Guidelines for Kidney Cancer provide multidisciplinary recommendations for diagnostic workup, staging, and treatment of patients with renal cell carcinoma (RCC). These NCCN Guidelines Insights focus on the systemic therapy options for patients with advanced RCC and summarize the new clinical data evaluated by the NCCN panel for the recommended therapies in Version 2.2024 of the NCCN Guidelines for Kidney Cancer.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/terapia , Neoplasias Renais/diagnóstico , Neoplasias Renais/terapia
2.
J Natl Compr Canc Netw ; 20(8): 866-878, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35948037

RESUMO

The NCCN Guidelines for Bladder Cancer provide recommendations for the diagnosis, evaluation, treatment, and follow-up of patients with bladder cancer and other urinary tract cancers (upper tract tumors, urothelial carcinoma of the prostate, primary carcinoma of the urethra). These NCCN Guidelines Insights summarize the panel discussion behind recent important updates to the guidelines regarding the treatment of non-muscle-invasive bladder cancer, including how to treat in the event of a bacillus Calmette-Guérin (BCG) shortage; new roles for immune checkpoint inhibitors in non-muscle invasive, muscle-invasive, and metastatic bladder cancer; and the addition of antibody-drug conjugates for metastatic bladder cancer.


Assuntos
Carcinoma de Células de Transição , Neoplasias da Bexiga Urinária , Administração Intravesical , Carcinoma de Células de Transição/patologia , Humanos , Masculino , Invasividade Neoplásica/patologia , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/terapia
3.
J Natl Compr Canc Netw ; 20(1): 71-90, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34991070

RESUMO

The NCCN Guidelines for Kidney Cancer focus on the screening, diagnosis, staging, treatment, and management of renal cell carcinoma (RCC). Patients with relapsed or stage IV RCC typically undergo surgery and/or receive systemic therapy. Tumor histology and risk stratification of patients is important in therapy selection. The NCCN Guidelines for Kidney Cancer stratify treatment recommendations by histology; recommendations for first-line treatment of ccRCC are also stratified by risk group. To further guide management of advanced RCC, the NCCN Kidney Cancer Panel has categorized all systemic kidney cancer therapy regimens as "Preferred," "Other Recommended Regimens," or "Useful in Certain Circumstances." This categorization provides guidance on treatment selection by considering the efficacy, safety, evidence, and other factors that play a role in treatment selection. These factors include pre-existing comorbidities, nature of the disease, and in some cases consideration of access to agents. This article summarizes surgical and systemic therapy recommendations for patients with relapsed or stage IV RCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/terapia , Humanos , Neoplasias Renais/diagnóstico , Neoplasias Renais/terapia , Oncologia
4.
J Natl Compr Canc Netw ; 19(3): 329-359, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33724754

RESUMO

This selection from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Colon Cancer focuses on systemic therapy options for the treatment of metastatic colorectal cancer (mCRC), because important updates have recently been made to this section. These updates include recommendations for first-line use of checkpoint inhibitors for mCRC, that is deficient mismatch repair/microsatellite instability-high, recommendations related to the use of biosimilars, and expanded recommendations for biomarker testing. The systemic therapy recommendations now include targeted therapy options for patients with mCRC that is HER2-amplified, or BRAF V600E mutation-positive. Treatment and management of nonmetastatic or resectable/ablatable metastatic disease are discussed in the complete version of the NCCN Guidelines for Colon Cancer available at NCCN.org. Additional topics covered in the complete version include risk assessment, staging, pathology, posttreatment surveillance, and survivorship.


Assuntos
Neoplasias do Colo , Medicamentos Biossimilares , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/genética , Neoplasias do Colo/terapia , Reparo de Erro de Pareamento de DNA , Humanos , Instabilidade de Microssatélites , Mutação
5.
J Natl Compr Canc Netw ; 18(7): 806-815, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32634771

RESUMO

The NCCN Guidelines for Rectal Cancer provide recommendations for the diagnosis, evaluation, treatment, and follow-up of patients with rectal cancer. These NCCN Guidelines Insights summarize the panel discussion behind recent important updates to the guidelines. These updates include clarifying the definition of rectum and differentiating the rectum from the sigmoid colon; the total neoadjuvant therapy approach for localized rectal cancer; and biomarker-targeted therapy for metastatic colorectal cancer, with a focus on new treatment options for patients with BRAF V600E- or HER2 amplification-positive disease.


Assuntos
Neoplasias do Colo , Neoplasias Retais , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/terapia , Humanos , Terapia Neoadjuvante , Guias de Prática Clínica como Assunto , Neoplasias Retais/diagnóstico , Neoplasias Retais/terapia
6.
J Natl Compr Canc Netw ; 18(3): 329-354, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32135513

RESUMO

This selection from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Bladder Cancer focuses on the clinical presentation and workup of suspected bladder cancer, treatment of non-muscle-invasive urothelial bladder cancer, and treatment of metastatic urothelial bladder cancer because important updates have recently been made to these sections. Some important updates include recommendations for optimal treatment of non-muscle-invasive bladder cancer in the event of a bacillus Calmette-Guérin (BCG) shortage and details about biomarker testing for advanced or metastatic disease. The systemic therapy recommendations for second-line or subsequent therapies have also been revised. Treatment and management of muscle-invasive, nonmetastatic disease is covered in the complete version of the NCCN Guidelines for Bladder Cancer available at NCCN.org. Additional topics covered in the complete version include treatment of nonurothelial histologies and recommendations for nonbladder urinary tract cancers such as upper tract urothelial carcinoma, urothelial carcinoma of the prostate, and primary carcinoma of the urethra.


Assuntos
Oncologia , Neoplasias da Bexiga Urinária , Feminino , Humanos , Masculino , Oncologia/normas , Neoplasias da Bexiga Urinária/epidemiologia
7.
J Natl Compr Canc Netw ; 17(9): 1109-1133, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31487687

RESUMO

Small bowel adenocarcinoma (SBA) is a rare malignancy of the gastrointestinal tract that has increased in incidence across recent years. Often diagnosed at an advanced stage, outcomes for SBA are worse on average than for other related malignancies, including colorectal cancer. Due to the rarity of this disease, few studies have been done to direct optimal treatment, although recent data have shown that SBA responds to treatment differently than colorectal cancer, necessitating a separate approach to treatment. The NCCN Guidelines for Small Bowel Adenocarcinoma were created to establish an evidence-based standard of care for patients with SBA. These guidelines provide recommendations on the workup of suspected SBA, primary treatment options, adjuvant treatment, surveillance, and systemic therapy for metastatic disease. Additionally, principles of imaging and endoscopy, pathologic review, surgery, radiation therapy, and survivorship are described.


Assuntos
Adenocarcinoma/diagnóstico , Adenocarcinoma/terapia , Neoplasias Intestinais/diagnóstico , Neoplasias Intestinais/terapia , Intestino Delgado/patologia , Guias de Prática Clínica como Assunto , Adenocarcinoma/etiologia , Adenocarcinoma/mortalidade , Terapia Combinada , Diagnóstico Diferencial , Humanos , Neoplasias Intestinais/etiologia , Neoplasias Intestinais/mortalidade , Estadiamento de Neoplasias , Fatores de Risco , Sobrevivência , Resultado do Tratamento , Conduta Expectante
8.
J Natl Compr Canc Netw ; 17(8): 977-1007, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31390582

RESUMO

In recent years, the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Adult Cancer Pain have undergone substantial revisions focusing on the appropriate and safe prescription of opioid analgesics, optimization of nonopioid analgesics and adjuvant medications, and integration of nonpharmacologic methods of cancer pain management. This selection highlights some of these changes, covering topics on management of adult cancer pain including pharmacologic interventions, nonpharmacologic interventions, and treatment of specific cancer pain syndromes. The complete version of the NCCN Guidelines for Adult Cancer Pain addresses additional aspects of this topic, including pathophysiologic classification of cancer pain syndromes, comprehensive pain assessment, management of pain crisis, ongoing care for cancer pain, pain in cancer survivors, and specialty consultations.


Assuntos
Dor do Câncer/diagnóstico , Dor do Câncer/terapia , Neoplasias/complicações , Manejo da Dor , Adulto , Fatores Etários , Dor do Câncer/etiologia , Terapia Combinada/efeitos adversos , Terapia Combinada/métodos , Humanos
9.
J Natl Compr Canc Netw ; 16(12): 1429-1440, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30545990

RESUMO

The NCCN Guidelines for Thyroid Carcinoma provide recommendations for the management of different types of thyroid carcinoma, including papillary, follicular, Hürthle cell, medullary, and anaplastic carcinomas. These NCCN Guidelines Insights summarize the panel discussion behind recent updates to the guidelines, including the expanding role of molecular testing for differentiated thyroid carcinoma, implications of the new pathologic diagnosis of noninvasive follicular thyroid neoplasm with papillary-like nuclear features, and the addition of a new targeted therapy option for BRAF V600E-mutated anaplastic thyroid carcinoma.


Assuntos
Carcinoma/terapia , Oncologia/normas , Neoplasias da Glândula Tireoide/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/normas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma/diagnóstico , Carcinoma/mortalidade , Carcinoma/patologia , Ensaios Clínicos como Assunto , Humanos , Biópsia Guiada por Imagem/métodos , Biópsia Guiada por Imagem/normas , Estadiamento de Neoplasias , Prognóstico , Inibidores de Proteínas Quinases/normas , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Proteínas Proto-Oncogênicas B-raf/genética , Sociedades Médicas/normas , Glândula Tireoide/diagnóstico por imagem , Glândula Tireoide/patologia , Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Tireoidectomia/métodos , Tireoidectomia/normas , Resultado do Tratamento , Estados Unidos
10.
J Natl Compr Canc Netw ; 16(9): 1041-1053, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30181416

RESUMO

The NCCN Clinical Practice Guidelines in Oncology for Bladder Cancer provide recommendations for the diagnosis, evaluation, treatment, and follow-up of patients with bladder cancer. These NCCN Guidelines Insights discuss important updates to the 2018 version of the guidelines, including implications of the 8th edition of the AJCC Cancer Staging Manual on treatment of muscle-invasive bladder cancer and incorporating newly approved immune checkpoint inhibitor therapies into treatment options for patients with locally advanced or metastatic disease.


Assuntos
Oncologia/normas , Neoplasias da Bexiga Urinária/terapia , Administração Intravesical , Assistência ao Convalescente/métodos , Assistência ao Convalescente/normas , Vacina BCG/uso terapêutico , Quimioterapia Adjuvante/efeitos adversos , Quimioterapia Adjuvante/métodos , Quimioterapia Adjuvante/normas , Cistectomia/efeitos adversos , Cistectomia/métodos , Cistectomia/normas , Humanos , Metástase Linfática/diagnóstico , Metástase Linfática/patologia , Oncologia/métodos , Terapia Neoadjuvante/efeitos adversos , Terapia Neoadjuvante/métodos , Terapia Neoadjuvante/normas , Estadiamento de Neoplasias , Tratamentos com Preservação do Órgão/efeitos adversos , Tratamentos com Preservação do Órgão/métodos , Tratamentos com Preservação do Órgão/normas , Seleção de Pacientes , Qualidade de Vida , Radioterapia Adjuvante/efeitos adversos , Radioterapia Adjuvante/métodos , Radioterapia Adjuvante/normas , Ensaios Clínicos Controlados Aleatórios como Assunto , Sociedades Médicas/normas , Resultado do Tratamento , Estados Unidos , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia
11.
J Natl Compr Canc Netw ; 16(1): 66-97, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29295883

RESUMO

This selection from the NCCN Guidelines for Adolescent and Young Adult (AYA) Oncology focuses on treatment and management considerations for AYA patients with cancer. Compared with older adults with cancer, AYA patients have unique needs regarding treatment, fertility counseling, psychosocial and behavioral issues, and supportive care services. The complete version of the NCCN Guidelines for AYA Oncology addresses additional aspects of caring for AYA patients, including risk factors, screening, diagnosis, and survivorship.


Assuntos
Neoplasias/diagnóstico , Neoplasias/terapia , Adolescente , Comportamento , Terapia Combinada/métodos , Gerenciamento Clínico , Feminino , Fertilidade , Humanos , Incidência , Neoplasias/epidemiologia , Neoplasias/etiologia , Cuidados Paliativos , Gravidez , Complicações Neoplásicas na Gravidez , Assistência Terminal , Adulto Jovem
12.
J Natl Compr Canc Netw ; 15(10): 1240-1267, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28982750

RESUMO

This selection from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Bladder Cancer focuses on systemic therapy for muscle-invasive urothelial bladder cancer, as substantial revisions were made in the 2017 updates, such as new recommendations for nivolumab, pembrolizumab, atezolizumab, durvalumab, and avelumab. The complete version of the NCCN Guidelines for Bladder Cancer addresses additional aspects of the management of bladder cancer, including non-muscle-invasive urothelial bladder cancer and nonurothelial histologies, as well as staging, evaluation, and follow-up.


Assuntos
Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/terapia , Terapia Combinada/métodos , Humanos , Invasividade Neoplásica , Metástase Neoplásica , Estadiamento de Neoplasias , Resultado do Tratamento , Neoplasias da Bexiga Urinária/mortalidade
13.
J Cancer ; 6(2): 98-104, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25561973

RESUMO

Fibrin plays an important role in lung metastasis. Here we show that fibrin promotes colony formation in primary kidney tumor cells from patients with kidney metastasis. In addition, we found that inhibition of fibrin formation with the thrombin inhibitor hirudin in nude mice in vivo significantly reduced the metastatic outgrowth of kidney tumor cells. Colony formation was significantly more efficient in tumor cells embedded in fibrin compared to matrigel and this effect correlates with the capacity of tumor cells to assemble a fibronectin matrix and generate stress fibers. Interestingly, stress fiber formation in fibrin was a specific function of metastatic kidney tumor cells while non-metastatic cells remained round. Inhibition of stress fiber formation with the Rho kinase inhibitor Y-27632, in turn, reduced fibronectin matrix assembly and colony formation in fibrin suggesting that spreading is a critical mechanism for the outgrowth of metastatic kidney tumor cells. Overall, our results indicate that adhesive interactions with fibrin play an important role for the progression of renal cell carcinoma and that inhibiting these interactions could be a promising strategy for treatment and prevention of kidney cancer metastasis.

14.
Mol Cancer Res ; 13(2): 273-80, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25205595

RESUMO

UNLABELLED: Chloride intracellular channel 1 (CLIC1) has been shown to be upregulated in various malignancies but its exact function remains unclear. Here, it is revealed that CLIC1 is critical for the stability of invadopodia in endothelial and tumor cells embedded in a 3-dimensional (3D) matrix of fibrin. Invadopodia stability was associated with the capacity of CLIC1 to induce stress fiber and fibronectin matrix formation following its ß3 integrin (ITGB3)-mediated recruitment into invadopodia. This pathway, in turn, was relevant for fibrin colonization as well as slug (SNAI2) expression and correlated with a significant role of CLIC1 in metastasis in vivo. Mechanistically, a reduction of myosin light chain kinase (MYLK) in CLIC1-depleted as well as ß3 integrin-depleted cells suggests an important role of CLIC1 for integrin-mediated actomyosin dynamics in cells embedded in fibrin. Overall, these results indicate that CLIC1 is an important contributor to tumor invasion, metastasis, and angiogenesis. IMPLICATIONS: This study uncovers an important new function of CLIC1 in the regulation of cell-extracellular matrix interactions and ability of tumor cells to metastasize to distant organs.


Assuntos
Canais de Cloreto/metabolismo , Matriz Extracelular/patologia , Metástase Neoplásica/patologia , Neovascularização Patológica/patologia , Adulto , Idoso , Linhagem Celular Tumoral , Canais de Cloreto/genética , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Integrina beta3/metabolismo , Masculino , Pessoa de Meia-Idade , Transplante de Neoplasias , Neovascularização Patológica/metabolismo , Transdução de Sinais , Fatores de Transcrição da Família Snail , Fatores de Transcrição/metabolismo
15.
Acta Biomater ; 10(4): 1558-70, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24361428

RESUMO

Hyaluronan (HA) is a linear polysaccharide with disaccharide repeats of d-glucuronic acid and N-acetyl-d-glucosamine. It is evolutionarily conserved and abundantly expressed in the extracellular matrix (ECM), on the cell surface and even inside cells. Being a simple polysaccharide, HA exhibits an astonishing array of biological functions. HA interacts with various proteins or proteoglycans to organize the ECM and to maintain tissue homeostasis. The unique physical and mechanical properties of HA contribute to the maintenance of tissue hydration, the mediation of solute diffusion through the extracellular space and the lubrication of certain tissues. The diverse biological functions of HA are manifested through its complex interactions with matrix components and resident cells. Binding of HA with cell surface receptors activates various signaling pathways, which regulate cell function, tissue development, inflammation, wound healing and tumor progression and metastasis. Taking advantage of the inherent biocompatibility and biodegradability of HA, as well as its susceptibility to chemical modification, researchers have developed various HA-based biomaterials and tissue constructs with promising and broad clinical potential. This paper illustrates the properties of HA from a matrix biology perspective by first introducing the principles underlying the biosynthesis and biodegradation of HA, as well as the interactions of HA with various proteins and proteoglycans. It next highlights the roles of HA in physiological and pathological states, including morphogenesis, wound healing and tumor metastasis. A deeper understanding of the mechanisms underlying the roles of HA in various physiological processes can provide new insights and tools for the engineering of complex tissues and tissue models.


Assuntos
Ácido Hialurônico/metabolismo , Animais , Tecnologia Biomédica , Humanos , Ácido Hialurônico/biossíntese , Ácido Hialurônico/química , Morfogênese , Neoplasias/metabolismo , Proteínas/metabolismo , Cicatrização
16.
Cancer Res ; 73(20): 6175-84, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23966293

RESUMO

The blood clotting cascade is selectively involved in lung metastasis, but the reason for this selectivity is unclear. Here, we show that tumor cells that metastasize predominantly to the lung, such as renal cell carcinoma (RCC) and soft tissue sarcoma (STS), have an inherent capacity to generate extensive invadopodia when embedded in a blood clot. Compared with other metastatic cancer cells tested, RCC and STS cells exhibited increased levels of expression of fibronectin and an activated form of the integrin αvß3, which coordinately supported the generation of an elaborate fibronectin matrix and actin stress fibers in fibrin-embedded tumor cells. Together, fibronectin and αvß3 induced upregulation of the transcription factor Slug, which mediates epithelial-mesenchymal transition as well as fibrin invasion and lung metastasis. This mechanism is clinically significant, because primary cancer cells from patients with metastatic RCC strongly invaded fibrin and this correlated with fibronectin matrix formation and Slug expression. In contrast, tumor cells from patients with localized RCC were largely noninvasive. Together, our findings establish that activated integrin αvß3 and fibronectin promote lung metastasis by upregulating Slug, defining a mechanism through which cancer cells can colonize blood clots in the lung vasculature.


Assuntos
Fibronectinas/metabolismo , Integrina alfaVbeta3/metabolismo , Neoplasias/sangue , Neoplasias/patologia , Fatores de Transcrição/metabolismo , Animais , Adesão Celular , Linhagem Celular Tumoral , Feminino , Fibronectinas/genética , Inativação Gênica , Humanos , Integrina alfaVbeta3/genética , Masculino , Camundongos Nus , Microscopia Confocal , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias/metabolismo , Fatores de Transcrição da Família Snail , Trombose/patologia , Fatores de Transcrição/genética , Regulação para Cima
17.
PLoS One ; 7(11): e50075, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23166824

RESUMO

To study the individual functions of hyaluronan interacting proteins in prostate cancer (PCa) motility through connective tissues, we developed a novel three-dimensional (3D) hyaluronic acid (HA) hydrogel assay that provides a flexible, quantifiable, and physiologically relevant alternative to current methods. Invasion in this system reflects the prevalence of HA in connective tissues and its role in the promotion of cancer cell motility and tissue invasion, making the system ideal to study invasion through bone marrow or other HA-rich connective tissues. The bio-compatible cross-linking process we used allows for direct encapsulation of cancer cells within the gel where they adopt a distinct, cluster-like morphology. Metastatic PCa cells in these hydrogels develop fingerlike structures, "invadopodia", consistent with their invasive properties. The number of invadopodia, as well as cluster size, shape, and convergence, can provide a quantifiable measure of invasive potential. Among candidate hyaluronan interacting proteins that could be responsible for the behavior we observed, we found that culture in the HA hydrogel triggers invasive PCa cells to differentially express and localize receptor for hyaluronan mediated motility (RHAMM)/CD168 which, in the absence of CD44, appears to contribute to PCa motility and invasion by interacting with the HA hydrogel components. PCa cell invasion through the HA hydrogel also was found to depend on the activity of hyaluronidases. Studies shown here reveal that while hyaluronidase activity is necessary for invadopodia and inter-connecting cluster formation, activity alone is not sufficient for acquisition of invasiveness to occur. We therefore suggest that development of invasive behavior in 3D HA-based systems requires development of additional cellular features, such as activation of motility associated pathways that regulate formation of invadopodia. Thus, we report development of a 3D system amenable to dissection of biological processes associated with cancer cell motility through HA-rich connective tissues.


Assuntos
Extensões da Superfície Celular/fisiologia , Proteínas da Matriz Extracelular/metabolismo , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/metabolismo , Hialuronoglucosaminidase/metabolismo , Hidrogéis/metabolismo , Invasividade Neoplásica/fisiopatologia , Neoplasias da Próstata/metabolismo , Biotinilação , Western Blotting , Ensaios de Migração Celular/instrumentação , Ensaios de Migração Celular/métodos , Proteínas da Matriz Extracelular/genética , Técnicas de Silenciamento de Genes , Humanos , Receptores de Hialuronatos/genética , Masculino , Neoplasias da Próstata/fisiopatologia , Reologia , Azul Tripano , Células Tumorais Cultivadas
18.
Biomaterials ; 33(35): 9049-60, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22999468

RESUMO

Cancer cells cultured in physiologically relevant, three-dimensional (3D) matrices can recapture many essential features of native tumor tissues. In this study, a hyaluronic acid (HA)-based bilayer hydrogel system that not only supports the tumoroid formation from LNCaP prostate cancer (PCa) cells, but also simulates their reciprocal interactions with the tumor-associated stroma was developed and characterized. HA hydrogels were prepared by mixing solutions of HA precursors functionalized with acrylate groups (HA-AC) and reactive thiols (HA-SH) under physiological conditions. The resultant viscoelastic gels have an average elastic modulus of 234 ± 30 Pa and can be degraded readily by hyaluronidase. The orthogonal and cytocompatible nature of the crosslinking chemistry permits facile incorporation of cytokine-releasing particles and PCa cells. In our bilayer hydrogel construct, the top layer contains heparin (HP)-decorated, HA-based hydrogel particles (HGPs) capable of releasing heparin-binding epidermal growth factor-like growth factor (HB-EGF) in a sustained manner at a rate of 2.5 wt%/day cumulatively. LNCaP cells embedded in the bottom layer receive the growth factor signals from the top, and in response form enlarging tumoroids with an average diameter of 85 µm by day 7. Cells in 3D hydrogels assemble into spherical tumoroids, form close cellular contacts through E-cadherin, and show cortical organization of F-actin, whereas those plated as 2D monolayers adopt a spread-out morphology. Compared to cells cultured on 2D, the engineered tumoroids significantly increased the expression of two pro-angiogenic factors, vascular endothelial growth factor-165 (VEGF(165)) and interleukin-8 (IL-8), both at mRNA and protein levels. Overall, the HA model system provides a useful platform for the study of tumor cell responses to growth factors and for screening of anticancer drugs targeting these pathways.


Assuntos
Ácido Hialurônico/química , Hidrogéis/química , Esferoides Celulares/citologia , Microambiente Tumoral/fisiologia , Actinas/genética , Actinas/metabolismo , Western Blotting , Caderinas/genética , Caderinas/metabolismo , Adesão Celular , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Heparina/química , Humanos , Hialuronoglucosaminidase/genética , Hialuronoglucosaminidase/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Masculino , Neoplasias da Próstata/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
RNA ; 17(2): 298-311, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21177376

RESUMO

Unlike ribonucleoprotein complexes that have a highly ordered overall architecture, such as the ribosome, yeast telomerase appears to be much more loosely constrained. Here, we investigate the importance of positioning of the Ku subunit within the 1157-nt yeast telomerase RNA (TLC1). Deletion of the 48-nt Ku-binding hairpin in TLC1 RNA (tlc1Δ48) reduces telomere length, survival of cells with gross chromosomal rearrangements, and de novo telomere addition at a broken chromosome end. To test the function of Ku at novel positions in the telomerase RNP, we reintroduced its binding site into tlc1Δ48 RNA at position 446 or 1029. We found that Ku bound to these repositioned sites in vivo and telomere length increased slightly, but statistically significantly. The ability of telomerase to promote survival of cells with gross chromosomal rearrangements by healing damaged chromosome arms was also partially restored, whereas the kinetics of DNA addition to a specific chromosome break was delayed. Having two Ku sites in TLC1 caused progressive hyperelongation of a variable subset of telomeres, consistent with Ku's role in telomerase recruitment to chromosome ends. The number of Ku-binding sites in TLC1 contributed to telomerase RNA abundance in vivo but was only partially responsible for telomere length phenotypes. Thus, telomerase RNA levels and telomere length regulation can be modulated by the number of Ku sites in telomerase RNA. Furthermore, there is substantial flexibility in the relative positioning of Ku in the telomerase RNP for native telomere length maintenance, although not as much flexibility as for the essential Est1p subunit.


Assuntos
Proteínas de Ligação a DNA/química , RNA/química , Ribonucleoproteínas/química , Proteínas de Saccharomyces cerevisiae/química , Telomerase/química , Sítios de Ligação , Proteínas de Ligação a DNA/metabolismo , Cinética , Modelos Biológicos , RNA/metabolismo , RNA Fúngico/química , RNA Fúngico/metabolismo , Ribonucleoproteínas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Telomerase/metabolismo , Telômero/química , Telômero/metabolismo
20.
J Biomater Sci Polym Ed ; 22(10): 1275-98, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20594408

RESUMO

Amphiphilic block co-polymers consisting of hydrophilic poly(ethylene glycol) and hydrophobic polyester bearing pendent cyclic ketals were synthesized by ring-opening co-polymerization of ε-caprolactone (CL) and 1,4,8-trioxaspiro-[4,6]-9-undecanone (TSU) using α-hydroxyl, ω-methoxy, poly(ethylene glycol) as the initiator and stannous octoate as the catalyst. Compositional analyses indicate that TSU was randomly distributed in the hydrophobic blocks. When the TSU content in the co-polymers increased, the polymer crystallinity decreased progressively and the glass transition temperature increased accordingly. The hydrophobic, anticancer drug, camptothecin (CPT), was successfully encapsulated in the block copolymer nanoparticles. The CPT encapsulation efficiency and release kinetics were strongly dependent on the co-polymer composition and crystallinity. CPT release from nanoparticles constructed from co-polymers containing 0, 39 and 100 mol% TSU in the hydrophobic block followed the same trend, with an initial burst of approx. 40% within one day followed by a moderate and slow release lasting up to 7 days. At a TSU content of 14 mol%, CPT was released in a continuous and controlled fashion with a reduced initial burst and a 73% cumulative release by day 7. The in vitro cytoxicity assay showed that the blank nanoparticles were not toxic to the cultured bone metastatic prostate cancer cells (C4-2B). Compared to the free drug, the encapsulated CPT was more effective in inducing apoptotic responses in C4-2B cells. Modulating the physical characteristics of the amphiphilic co-polymers via co-polymerization offers a facile method for controlling the bioavailability of anticancer drugs, ultimately increasing effectiveness and minimizing toxicity.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Camptotecina/administração & dosagem , Portadores de Fármacos , Nanopartículas , Polietilenoglicóis/química , Tensoativos , Antineoplásicos Fitogênicos/farmacocinética , Apoptose/efeitos dos fármacos , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/fisiopatologia , Neoplasias Ósseas/secundário , Camptotecina/farmacocinética , Caproatos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Vidro/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Lactonas/química , Masculino , Nanopartículas/química , Tamanho da Partícula , Poliésteres/síntese química , Poliésteres/química , Polietilenoglicóis/síntese química , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/fisiopatologia , Tensoativos/síntese química , Tensoativos/química , Temperatura de Transição
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