RESUMO
Neutrophils promote tumor growth and metastasis at multiple stages of cancer progression. One mechanism through which this occurs is via release of neutrophil extracellular traps (NETs). We have previously shown that NETs trap tumor cells in both the liver and the lung, increasing their adhesion and metastasis following postoperative complications. Multiple studies have since shown that NETs play a role in tumor progression and metastasis. NETs are composed of nuclear DNA-derived web-like structures decorated with neutrophil-derived proteins. However, it is unknown which, if any, of these NET-affiliated proteins is responsible for inducing the metastatic phenotype. In this study, we identify the NET-associated carcinoembryonic Ag cell adhesion molecule 1 (CEACAM1) as an essential element for this interaction. Indeed, blocking CEACAM1 on NETs, or knocking it out in a murine model, leads to a significant decrease in colon carcinoma cell adhesion, migration and metastasis. Thus, this work identifies NET-associated CEACAM1 as a putative therapeutic target to prevent the metastatic progression of colon carcinoma.
Assuntos
Antígenos CD/metabolismo , Antígeno Carcinoembrionário/metabolismo , Moléculas de Adesão Celular/metabolismo , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Armadilhas Extracelulares/imunologia , Armadilhas Extracelulares/metabolismo , Neutrófilos/imunologia , Células A549 , Animais , Linhagem Celular Tumoral , Neoplasias do Colo/imunologia , Células HT29 , Humanos , Camundongos , Neutrófilos/patologiaRESUMO
: Since their discovery, neutrophil extracellular traps (NETs) have been implicated in a broad array of functions, both beneficial and detrimental to the host. Indeed, NETs have roles in infection, sepsis, wound healing, thrombotic disease, and cancer propagation, all of which are directly implicated in the care of surgical patients. Here we provide an updated review on the role of NETs in the perioperative period with specific emphasis on perioperative infections, wound healing, vascular complications, cancer propagation, as well as discussing ongoing, and future therapeutic targets. Surgeons will benefit from understanding the latest discoveries in neutrophil biology and how these novel functions affect the care of surgical patients. Furthermore, novel anti-NET therapies are being developed which may have profound effects on the care of surgical patients.
Assuntos
Armadilhas Extracelulares/metabolismo , Neutrófilos/metabolismo , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Procedimentos Cirúrgicos Operatórios/métodos , Infecção da Ferida Cirúrgica/metabolismo , Cicatrização/fisiologia , Animais , Biomarcadores/metabolismo , Feminino , Humanos , Masculino , Camundongos , Assistência Perioperatória/métodos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/metabolismo , Medição de Risco , Sensibilidade e Especificidade , Infecção da Ferida Cirúrgica/diagnósticoRESUMO
Despite advances in cancer treatment, metastasis remains today the main cause of cancer death. Local control through complete surgical resection of the primary tumor continues to be a key principle in cancer treatment. However, surgical interventions themselves lead to adverse oncologic outcomes and are associated with significantly increased rates of metastasis. Neutrophils through release of neutrophil extracellular traps (NETs) in response to infections were shown to be able to capture circulating cancer cells, and in doing so, support the development of metastatic disease. To be able to intervene on this process, understanding the exact molecular nature of these mechanisms is crucial. We therefore hypothesize and demonstrate that ß1-integrin is an important factor mediating the interactions between circulating tumor cells and NETs. We show that ß1-integrin expression on both cancer cells and NETs is important for the adhesion of circulating tumor cells to NETs both in vitro and in vivo. Using a murine model of intra-abdominal sepsis to mimic the postoperative inflammatory environment, we show that ß1-integrin expression is upregulated in the context of inflammation in vivo. Ultimately, we show that this increased early cancer cell adhesion to NETs in vivo and this effect is abrogated when mice are administered DNAse 1. Our data therefore sheds light on the first molecular mechanism by which NETs can trap circulating tumor cells (CTCs), broadening our understanding of this process.
Assuntos
Armadilhas Extracelulares/metabolismo , Inflamação/patologia , Integrina beta1/metabolismo , Neoplasias Pulmonares/patologia , Células Neoplásicas Circulantes/patologia , Neutrófilos/patologia , Animais , Western Blotting , Adesão Celular , Proliferação de Células , Modelos Animais de Doenças , Citometria de Fluxo , Imunofluorescência , Humanos , Inflamação/metabolismo , Integrina beta1/química , Integrina beta1/genética , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células Neoplásicas Circulantes/metabolismo , Infiltração de Neutrófilos , RNA Interferente Pequeno/genética , Células Tumorais CultivadasRESUMO
BACKGROUND: Several regulatory agencies have approved the use of the neoadjuvant chemo-immunotherapy for resectable stage II and III of non-small cell lung cancer (NSCLC) and numerous trials investigating novel agents are underway. However, significant concerns exist around the feasibility and safety of offering curative surgery to patients treated within such pathways. The goal in this study was to evaluate the impact of a transition towards a large-scale neoadjuvant therapy program for NSCLC. METHODS: Medical charts of patients with clinical stage II and III NSCLC who underwent resection from January 2015 to December 2020 were reviewed. The primary outcome was perioperative complication rate between neoadjuvant-treated versus upfront surgery patients. Multivariable logistic regression estimated occurrence of postoperative complications and overall survival was assessed as an exploratory secondary outcome by Kaplan-Meier and Cox-regression analyses. RESULTS: Of the 428 patients included, 106 (24.8%) received neoadjuvant therapy and 322 (75.2%) upfront surgery. Frequency of minor and major postoperative complications was similar between groups (P = .22). Occurrence in postoperative complication was similar in both cohort (aOR = 1.31, 95% CI 0.73-2.34). Neoadjuvant therapy administration increased from 10% to 45% with a rise in targeted and immuno-therapies over time, accompanied by a reduced rate of preoperative radiation therapy use. 1-, 2-, and 5-year overall survival was higher in neoadjuvant therapy compared to upfront surgery patients (Log-Rank P = .017). CONCLUSIONS: No significant differences in perioperative outcomes and survival were observed in resectable NSCLC patients treated by neoadjuvant therapy versus upfront surgery. Transition to neoadjuvant therapy among resectable NSCLC patients is safe and feasible from a surgical perspective.
Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Terapia Neoadjuvante , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Terapia Neoadjuvante/métodos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Pneumonectomia , Estudos Retrospectivos , Taxa de Sobrevida , Complicações Pós-Operatórias/epidemiologia , Resultado do Tratamento , Estadiamento de Neoplasias , SeguimentosRESUMO
Obesity is characterized by chronic systemic inflammation and enhances cancer metastasis and mortality. Obesity promotes breast cancer metastasis to lung in a neutrophil-dependent manner; however, the upstream regulatory mechanisms of this process remain unknown. Here, we show that obesity-induced monocytes underlie neutrophil activation and breast cancer lung metastasis. Using mass cytometry, obesity favors the expansion of myeloid lineages while restricting lymphoid cells within the peripheral blood. RNA sequencing and flow cytometry revealed that obesity-associated monocytes resemble professional antigen-presenting cells due to a shift in their development and exhibit enhanced MHCII expression and CXCL2 production. Monocyte induction of the CXCL2-CXCR2 axis underlies neutrophil activation and release of neutrophil extracellular traps to promote metastasis, and enhancement of this signaling axis is observed in lung metastases from obese cancer patients. Our findings provide mechanistic insight into the relationship between obesity and cancer by broadening our understanding of the interactive role that myeloid cells play in this process.
Assuntos
Neoplasias da Mama , Neoplasias Pulmonares , Humanos , Feminino , Monócitos/patologia , Neoplasias Pulmonares/patologia , Obesidade/metabolismo , Células Mieloides/metabolismo , Neoplasias da Mama/patologia , InflamaçãoRESUMO
The biological effects of ionizing radiation depend on the tissue, tumor type, radiation quality, and patient-specific factors. Inter-patient variation in cell/nucleus size may influence patient-specific dose response. However, this variability in dose response is not well investigated due to lack of available cell/nucleus size data. The aim of this study was to develop methods to derive cell/nucleus size distributions from digital images of 2D histopathological samples and use them to build digital 3D models for use in cellular dosimetry. Nineteen of sixty hematoxylin and eosin stained lung adenocarcinoma samples investigated passed exclusion criterion to be analyzed in the study. A difference of gaussians blob detection algorithm was used to identify nucleus centers and quantify cell spacing. Hematoxylin content was measured to determine nucleus radius. Pouring simulations were conducted to generate one-hundred 3D models containing volumes of equivalent cell spacing and nuclei radius to those in histopathological samples. The nuclei radius distributions of non-tumoral and cancerous regions appearing in the same slide were significantly different (p < 0.01) in all samples analyzed. The median nuclear-cytoplasmic ratio was 0.36 for non-tumoral cells and 0.50 for cancerous cells. The average cellular and nucleus packing densities in the 3D models generated were 65.9% (SD: 1.5%) and 13.3% (SD: 0.3%) respectively. Software to determine cell spacing and nuclei radius from histopathological samples was developed. 3D digital tissue models containing volumes with equivalent cell spacing, nucleus radius, and packing density to cancerous tissues were generated.
Assuntos
Algoritmos , Radiometria , Núcleo Celular , HumanosRESUMO
Radiation therapy (RT) is used in the management of several cancers; however, tumor radioresistance remains a challenge. Polymorphonuclear neutrophils (PMNs) are recruited to the tumor immune microenvironment (TIME) post-RT and can facilitate tumor progression by forming neutrophil extracellular traps (NETs). Here, we demonstrate a role for NETs as players in tumor radioresistance. Using a syngeneic bladder cancer model, increased NET deposition is observed in the TIME of mice treated with RT and inhibition of NETs improves overall radiation response. In vitro, the protein HMGB1 promotes NET formation through a TLR4-dependent manner and in vivo, inhibition of both HMGB1 and NETs significantly delays tumor growth. Finally, NETs are observed in bladder tumors of patients who did not respond to RT and had persistent disease post-RT, wherein a high tumoral PMN-to-CD8 ratio is associated with worse overall survival. Together, these findings identify NETs as a potential therapeutic target to increase radiation efficacy.
Assuntos
Armadilhas Extracelulares/metabolismo , Neutrófilos/imunologia , Tolerância a Radiação/imunologia , Neoplasias da Bexiga Urinária/radioterapia , Idoso , Idoso de 80 Anos ou mais , Animais , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Feminino , Proteína HMGB1/antagonistas & inibidores , Proteína HMGB1/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/imunologia , Microambiente Tumoral/imunologia , Neoplasias da Bexiga Urinária/patologiaRESUMO
INTRODUCTION: Primary carcinomas of the trachea are rare, with a reported annual incidence of one in a million. We present a case of a previously undescribed polypoid high-grade neuroendocrine carcinoma of the trachea. Resection of the carcinoma revealed only superficial invasion of the mucosa and without evidence of local or distant metastatic disease. Histologically, the tumor had high-grade features with necrosis and a high mitotic index. METHODS: Characterization of this rare neuroendocrine carcinoma of the trachea was performed by immunohistochemistry and whole-genome sequencing. RESULTS: Immunohistochemistry result was positive for neuroendocrine markers, p16 and an elevated Ki-67. Whole-genome sequencing of the lesion was performed and revealed a very unusual and very distinct mutational signature without relationship to other relevant neuroendocrine carcinomas. Neither known driver nor targetable mutations were found by whole-genome sequencing. Analysis of the sequence of numerous viral elements of human papillomavirus-18 suggests that the pathogenesis of the lesion is related to viral integration. The patient developed distal recurrence, which progressed to widespread pulmonary dissemination, presumably through aerogenous spread of disease. CONCLUSIONS: This is the first characterization of this type of tracheal tumor, including genomic findings, pathogenesis, and natural history.
RESUMO
Metastasis is the leading cause of cancer-related deaths, and obesity is associated with increased breast cancer (BC) metastasis. Preclinical studies have shown that obese adipose tissue induces lung neutrophilia associated with enhanced BC metastasis to this site. Here we show that obesity leads to neutrophil-dependent impairment of vascular integrity through loss of endothelial adhesions, enabling cancer cell extravasation into the lung. Mechanistically, neutrophil-produced reactive oxygen species in obese mice increase neutrophil extracellular DNA traps (NETs) and weaken endothelial junctions, facilitating the influx of tumor cells from the peripheral circulation. In vivo treatment with catalase, NET inhibitors or genetic deletion of Nos2 reversed this effect in preclinical models of obesity. Imaging mass cytometry of lung metastasis samples from patients with cancer revealed an enrichment in neutrophils with low catalase levels correlating with elevated body mass index. Our data provide insights into potentially targetable mechanisms that underlie the progression of BC in the obese population.
Assuntos
Neoplasias da Mama , Neoplasias Pulmonares , Animais , Neoplasias da Mama/metabolismo , Catalase/metabolismo , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Camundongos , Neutrófilos/metabolismo , Obesidade/complicações , Estresse OxidativoRESUMO
Neutrophils represent the immune system's first line of defense and are rapidly recruited into inflamed tissue. In cancer associated inflammation, phenotypic heterogeneity has been ascribed to this cell type, whereby neutrophils can manifest anti- or pro-metastatic functions depending on the cellular/micro-environmental context. Here, we demonstrate that pro-metastatic immature low-density neutrophils (iLDNs) more efficiently accumulate in the livers of mice bearing metastatic lesions compared with anti-metastatic mature high-density neutrophils (HDNs). Transcriptomic analyses reveal enrichment of a migration signature in iLDNs relative to HDNs. We find that conditioned media derived from liver-metastatic breast cancer cells, but not lung-metastatic variants, specifically induces chemotaxis of iLDNs and not HDNs. Chemotactic responses are due to increased surface expression of C3aR in iLDNs relative to HDNs. In addition, we detect elevated secretion of cancer-cell derived C3a from liver-metastatic versus lung-metastatic breast cancer cells. Perturbation of C3a/C3aR signaling axis with either a small molecule inhibitor, SB290157, or reducing the levels of secreted C3a from liver-metastatic breast cancer cells by short hairpin RNAs, can abrogate the chemotactic response of iLDNs both in vitro and in vivo, respectively. Together, these data reveal novel mechanisms through which iLDNs prefentially accumulate in liver tissue harboring metastases in response to tumor-derived C3a secreted from the liver-aggressive 4T1 breast cancer cells.
Assuntos
Complemento C3a/imunologia , Neoplasias Hepáticas/imunologia , Neutrófilos/imunologia , Animais , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Meios de Cultivo Condicionados , Feminino , Neoplasias Hepáticas/secundário , Camundongos , Camundongos Endogâmicos BALB C , Metástase Neoplásica , Receptores de Complemento/agonistas , Receptores de Complemento/metabolismoRESUMO
Targeting the dynamic tumor immune microenvironment (TIME) can provide effective therapeutic strategies for cancer. Neutrophils are the predominant leukocyte population in mice and humans, and mounting evidence implicates these cells during tumor growth and metastasis. Neutrophil extracellular traps (NETs) are networks of extracellular neutrophil DNA fibers that are capable of binding tumor cells to support metastatic progression. Here we demonstrate for the first time that circulating NET levels are elevated in advanced esophageal, gastric and lung cancer patients compared to healthy controls. Using pre-clinical murine models of lung and colon cancer in combination with intravital video microscopy, we show that NETs functionally regulate disease progression and that blocking NETosis through multiple strategies significantly inhibits spontaneous metastasis to the lung and liver. Further, we visualize how inhibiting tumor-induced NETs decreases cancer cell adhesion to liver sinusoids following intrasplenic injection - a mechanism previously thought to be driven primarily by exogenous stimuli. Thus, in addition to neutrophil abundance, the functional contribution of NETosis within the TIME has critical translational relevance and represents a promising target to impede metastatic dissemination.
Assuntos
Apoptose/imunologia , Armadilhas Extracelulares/metabolismo , Metástase Neoplásica/imunologia , Neoplasias/patologia , Neutrófilos/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Adesão Celular/imunologia , Linhagem Celular Tumoral/transplante , Modelos Animais de Doenças , Progressão da Doença , Armadilhas Extracelulares/efeitos dos fármacos , Feminino , Humanos , Microscopia Intravital , Masculino , Camundongos , Pessoa de Meia-Idade , Metástase Neoplásica/prevenção & controle , Neoplasias/sangue , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Cultura Primária de Células , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Adulto JovemRESUMO
The growth of cancer metastases in the liver depends on a permissive interaction with the hepatic microenvironment and neutrophils can contribute to this interaction, either positively or negatively, depending on their phenotype. Here we investigated the role of IGF-I in the control of the tumor microenvironment in the liver, using mice with a conditional, liver-specific, IGF-I deficiency (iLID) induced by a single tamoxifen injection. In mice that had a sustained (3 weeks) IGF-I deficiency prior to the intrasplenic/portal inoculation of colon carcinoma MC-38 cells, we observed an increase in neutrophil accumulation in the liver relative to controls. However, unlike controls, these neutrophils did not acquire the (anti-inflammatory) tumor-promoting phenotype, as evidenced by retention of high ICAM-1 expression and nitric oxide production and low CXCR4, CCL5, and VEGF expression and arginase production, all characteristic of the (pro-inflammatory) phenotype. This coincided with an increase in apoptotic tumor cells and reduced metastasis. Neutrophils isolated from these mice also had reduced IGF-IR expression levels. These changes were not observed in iLID mice with a short-term (2 days) IGF-I depletion, despite a 70% reduction in their circulating IGF-I levels, indicating that a sustained IGF-I deficiency was necessary to alter the neutrophil phenotype. Similar results were obtained with the highly metastatic Lewis lung carcinoma subline H-59 cells and in mice injected with an IGF-Trap that blocks IGF-IR signaling by reducing ligand bioavailability. Our results implicate the IGF axis in neutrophil polarization and the induction of a pro-metastatic microenvironment in the liver.
RESUMO
Liver metastases remain a major cause of death from gastrointestinal tract cancers as well as from other malignancies such as breast and lung carcinomas and melanoma. Understanding the underlying biology is essential for the design of effective targeted therapies. We previously reported that collagen IV α1/α2 overexpression in non-metastatic lung carcinoma (M27colIV) cells increased their metastatic ability, specifically to the liver and documented high collagen IV levels in surgical resections of liver metastases from diverse tumor types. Here, we aimed to elucidate the functional relevance of collagen IV to metastatic outgrowth in the liver. Gene expression profiling revealed in M27colIVcells significant increases in the expression of chemokines CCL5 (5.7-fold) and CCL7 (2.6-fold) relative to wild-type cells, and this was validated by qPCR and western blotting. Similarly, in human colon carcinoma KM12C and KM12SM cells with divergent liver-colonizing potentials, CCL7 and CCL5 production correlated with type IV collagen expression and the metastatic phenotype. CCL7 silencing by short hairpin RNA (shRNA) reduced experimental liver metastasis in both cell types, whereas CCL5 silencing reduced metastasis of M27colIV cells, implicating these cytokines in metastatic expansion in the liver. Subsequent functional analyses implicated both MEK/ERK and PI3K signaling upstream of CCL7 upregulation and identified CCL7 (but not CCL5) as a critical migration/invasion factor, acting via the chemokine receptor CCR3. Chemokine CCL5 was identified as a regulator of the T-cell immune response in the liver. Loss of CCL7 in KM12SM cells was also associated with altered E-cadherin and reduced vimentin and Snail expression, implicating it in epithelial-to-mesenchymal transition in these cells. Moreover, in clinical specimens of colon cancer liver metastases analyzed by immunohistochemistry, CCL5 and CCL7 levels paralleled those of collagen IV. The results identify the chemokines CCL5 and CCL7 as type IV collagen-regulated genes that promote liver metastasis by distinct and complementary mechanisms.
Assuntos
Quimiocina CCL5/metabolismo , Quimiocina CCL7/metabolismo , Colágeno Tipo IV/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Animais , Caderinas/metabolismo , Carcinoma Pulmonar de Lewis , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Transição Epitelial-Mesenquimal/fisiologia , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/fisiologia , Fatores de Transcrição da Família Snail/metabolismo , Regulação para Cima/fisiologia , Vimentina/metabolismoRESUMO
OBJECTIVE: The purpose of this study was to determine the prevalence of factor V Leiden, prothrombin, and methylene tetrahydrofolate reductase gene mutations in women with adverse pregnancy outcome compared with women who had uneventful pregnancies. STUDY DESIGN: Between 2003 and 2005, pregnant women with > or = 1 unexplained second trimester abortion, > or = 1 intrauterine fetal death, severe preeclampsia, or severe intrauterine growth restriction (study subjects) were compared with control subjects (uneventful pregnancy) for the frequency of the mutations. RESULTS: The cases of 91 patients in each arm were analyzed. Obstetric complications were second trimester abortions (16.5%), intrauterine fetal death (53.8%), preeclampsia (8.8%), and severe intrauterine growth restriction (20.9%). Study subjects were more likely to be older and multiparous compared with control subjects. The 2 groups showed no difference in the incidence of smoking or family history of thrombosis, but study subjects were more likely to have a positive family history of obstetric complications. The prevalence of factor V Leiden (12.1% vs 18.7%; P = .304), prothrombin (7.7% vs 5.5%; P = .765), methylene tetrahydrofolate reductase gene mutations (53.8% vs 65.9%; P = .130), and > 1 mutation (11.0% vs 17.6%; P = .290) was not significantly different between study subjects and control subjects. CONCLUSION: Factor V Leiden, prothrombin, and methylene tetrahydrofolate reductase gene mutations did not seem to play a significant role in adverse pregnancy outcome in our population.
Assuntos
Fator V/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Mutação , Complicações na Gravidez/genética , Protrombina/genética , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Gravidez , PrevalênciaRESUMO
The IGFI receptor promotes malignant progression and has been recognized as a target for cancer therapy. Clinical trials with anti-IGFIR antibodies provided evidence of therapeutic efficacy but exposed limitations due in part to effects on, and the compensatory function of, the insulin receptor system. Here, we report on the production, characterization, and biologic activity of a novel, IGF-targeting protein (the IGF-Trap) comprising a soluble form of hIGFIR and the Fc portion of hIgG1. The IGF-Trap has a high affinity for hIGFI and hIGFII but low affinity for insulin, as revealed by surface plasmon resonance. It efficiently blocked IGFIR signaling in several carcinoma cell types and inhibited tumor cell proliferation, migration, and invasion in vitro. In vivo, the IGF-Trap showed favorable pharmacokinetic properties and could suppress the growth of established breast carcinoma tumors when administered therapeutically into tumor-bearing mice, improving disease-free survival. Moreover, IGF-Trap treatment markedly reduced experimental liver metastasis of colon and lung carcinoma cells, increasing tumor cell apoptosis and reducing angiogenesis. Finally, when compared with an anti-IGFIR antibody or IGF-binding protein-1 that were used at similar or higher concentrations, the IGF-Trap showed superior therapeutic efficacy to both inhibitors. Taken together, we have developed a targeted therapeutic molecule with highly potent anticancer effects that could address limitations of current IGFIR-targeting agents.
Assuntos
Antineoplásicos/farmacologia , Carcinoma/metabolismo , Carcinoma/patologia , Receptor IGF Tipo 1/antagonistas & inibidores , Proteínas Recombinantes de Fusão/farmacologia , Animais , Especificidade de Anticorpos , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Células CHO , Carcinoma/tratamento farmacológico , Carcinoma/mortalidade , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cricetulus , Modelos Animais de Doenças , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Cinética , Camundongos , Metástase Neoplásica , Ligação Proteica , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoAssuntos
Conservadores da Densidade Óssea/uso terapêutico , Difosfonatos/uso terapêutico , Imidazóis/uso terapêutico , Osteoporose/tratamento farmacológico , Polimorfismo de Nucleotídeo Único/genética , Receptores de Calcitriol/genética , Densidade Óssea/efeitos dos fármacos , Estudos de Coortes , Genótipo , Humanos , Osteoporose/etiologia , Talassemia/complicações , Ácido ZoledrônicoRESUMO
The dynamics of four regions of tropomyosin was assessed using saturation transfer electron paramagnetic resonance in the muscle fiber. In order to fully immobilize the spin probe on the surface of tropomyosin, a bi-functional spin label was attached to i,i+4 positions via cysteine mutagenesis. The dynamics of bi-functionally labeled tropomyosin mutants decreased by three orders of magnitude when reconstituted into "ghost muscle fibers". The rates of motion varied along the length of tropomyosin with the C-terminus position 268/272 being one order of magnitude slower then N-terminal domain or the center of the molecule. Introduction of troponin decreases the dynamics of all four sites in the muscle fiber, but there was no significant effect upon addition of calcium or myosin subfragment-1.