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Prostate cancer (PC) has a high propensity to develop bone metastases, causing severe pain and pathological fractures that profoundly impact a patients' normal functions. Current clinical intervention is mainly palliative focused on pain management, and tumor progression is refractory to standard therapeutic regimens. This limited treatment efficacy is at least partially due to a lack of comprehensive understanding of the molecular landscape of the disease pathology, along with the intensive overlapping of physiological and pathological molecular signaling. The niche is overwhelmed with diverse cell types with inter- and intra-heterogeneity, along with growth factor-enriched cells that are supportive of invading cell proliferation, providing an additional layer of complexity. This review seeks to provide molecular insights into mechanisms underlying PC bone metastasis development and progression.
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Neoplasias Ósseas , Neoplasias da Próstata , Humanos , Neoplasias Ósseas/secundário , Neoplasias Ósseas/patologia , Neoplasias Ósseas/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/genética , Masculino , Animais , Microambiente Tumoral , Transdução de SinaisRESUMO
Primary, glioblastoma, and secondary brain tumors, from metastases outside the brain, are among the most aggressive and therapeutically resistant cancers. A physiological barrier protecting the brain, the blood-brain barrier (BBB), functions as a deterrent to effective therapies. To enhance cancer therapy, we developed a cancer terminator virus (CTV), a unique tropism-modified adenovirus consisting of serotype 3 fiber knob on an otherwise Ad5 capsid that replicates in a cancer-selective manner and simultaneously produces a potent therapeutic cytokine, melanoma differentiation-associated gene-7/interleukin-24 (MDA-7/IL-24). A limitation of the CTV and most other viruses, including adenoviruses, is an inability to deliver systemically to treat brain tumors because of the BBB, nonspecific virus trapping, and immune clearance. These obstacles to effective viral therapy of brain cancer have now been overcome using focused ultrasound with a dual microbubble treatment, the focused ultrasound-double microbubble (FUS-DMB) approach. Proof-of-principle is now provided indicating that the BBB can be safely and transiently opened, and the CTV can then be administered in a second set of complement-treated microbubbles and released in the brain using focused ultrasound. Moreover, the FUS-DMB can be used to deliver the CTV multiple times in animals with glioblastoma growing in their brain thereby resulting in a further enhancement in survival. This strategy permits efficient therapy of primary and secondary brain tumors enhancing animal survival without promoting harmful toxic or behavioral side effects. Additionally, when combined with a standard of care therapy, Temozolomide, a further increase in survival is achieved. The FUS-DMB approach with the CTV highlights a noninvasive strategy to treat brain cancers without surgery. This innovative delivery scheme combined with the therapeutic efficacy of the CTV provides a novel potential translational therapeutic approach for brain cancers.
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Adenoviridae , Barreira Hematoencefálica , Neoplasias Encefálicas , Animais , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/virologia , Humanos , Adenoviridae/genética , Interleucinas/genética , Linhagem Celular Tumoral , Microbolhas/uso terapêutico , Camundongos , Glioblastoma/terapia , Glioblastoma/virologia , Glioblastoma/patologia , Ensaios Antitumorais Modelo de Xenoenxerto , Terapia Viral Oncolítica/métodos , Vetores Genéticos/administração & dosagem , Temozolomida/uso terapêutico , Camundongos NusRESUMO
Bone metastasis is a frequent and incurable consequence of advanced prostate cancer (PC). An interplay between disseminated tumor cells and heterogeneous bone resident cells in the metastatic niche initiates this process. Melanoma differentiation associated gene-9 (mda-9/Syntenin/syndecan binding protein) is a prometastatic gene expressed in multiple organs, including bone marrow-derived mesenchymal stromal cells (BM-MSCs), under both physiological and pathological conditions. We demonstrate that PDGF-AA secreted by tumor cells induces CXCL5 expression in BM-MSCs by suppressing MDA-9-dependent YAP/MST signaling. CXCL5-derived tumor cell proliferation and immune suppression are consequences of the MDA-9/CXCL5 signaling axis, promoting PC disease progression. mda-9 knockout tumor cells express less PDGF-AA and do not develop bone metastases. Our data document a previously undefined role of MDA-9/Syntenin in the tumor and microenvironment in regulating PC bone metastasis. This study provides a framework for translational strategies to ameliorate health complications and morbidity associated with advanced PC.
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Neoplasias Ósseas , Melanoma , Neoplasias da Próstata , Masculino , Humanos , Sinteninas/genética , Sinteninas/metabolismo , Melanoma/metabolismo , Neoplasias da Próstata/genética , Transdução de Sinais/genética , Neoplasias Ósseas/genética , Linhagem Celular Tumoral , Microambiente Tumoral , Metástase NeoplásicaRESUMO
BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer without effective therapies and with poor prognosis, causing 7% of all cancer-related fatalities in the USA. Considering the lack of effective therapies for this aggressive cancer, there is an urgent need to define newer and more effective therapeutic strategies. Polyinosine-polycytidylic acid (pIC) is a synthetic double-stranded RNA (dsRNA) which directly activates dendritic cells and natural killer cells inhibiting tumor growth. When pIC is delivered into the cytoplasm using polyethyleneimine (PEI), pIC-PEI, programmed-cell death is induced in PDAC. Transfection of [pIC]PEI into PDAC cells inhibits growth, promotes toxic autophagy and also induces apoptosis in vitro and in vivo in animal models. METHODS: The KPC transgenic mouse model that recapitulates PDAC development in patients was used to interrogate the role of an intact immune system in vivo in PDAC in response to [pIC]PEI. Antitumor efficacy and survival were monitored endpoints. Comprehensive analysis of the tumor microenvironment (TME) and immune cells, cytokines and chemokines in the spleen, and macrophage polarization were analyzed. RESULTS: Cytosolic delivery of [pIC]PEI induces apoptosis and provokes strong antitumor immunity in vivo in immune competent mice with PDAC. The mechanism underlying the immune stimulatory properties of [pIC]PEI involves Stat1 activation resulting in CCL2 and MMP13 stimulation thereby provoking macrophage polarization. [pIC]PEI induces apoptosis via the AKT-XIAP pathway, as well as macrophage differentiation and T-cell activation via the IFNγ-Stat1-CCL2 signaling pathways in PDAC. In transgenic tumor mouse models, [pIC]PEI promotes robust and profound antitumor activity implying that stimulating the immune system contributes to biological activity. The [pIC]PEI anti-PDAC effects are enhanced when used in combination with a standard of care (SOC) treatment, that is, gemcitabine. CONCLUSIONS: In summary, [pIC]PEI treatment is non-toxic toward normal pancreatic cells while displaying strong cytotoxic and potent immune activating activities in PDAC, making it an attractive therapeutic when used alone or in conjunction with SOC therapeutic agents, potentially providing a safe and effective treatment protocol with translational potential for the effective therapy of PDAC.
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Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animais , Humanos , Camundongos , Carcinoma Ductal Pancreático/genética , Quimiocina CCL2/metabolismo , Quimiocina CCL2/uso terapêutico , Citoplasma/metabolismo , Citoplasma/patologia , Camundongos Transgênicos , Neoplasias Pancreáticas/metabolismo , Poli C/uso terapêutico , Fator de Transcrição STAT1/metabolismo , Microambiente TumoralRESUMO
Genome-wide gene expression analysis and animal modeling indicate that melanoma differentiation associated gene-9 (mda-9, Syntenin, Syndecan binding protein, referred to as MDA-9/Syntenin) positively regulates melanoma metastasis. The MDA-9/Syntenin protein contains two tandem PDZ domains serving as a nexus for interactions with multiple proteins that initiate transcription of metastasis-associated genes. Although targeting either PDZ domain abrogates signaling and prometastatic phenotypes, the integrity of both domains is critical for full biological function. Fragment-based drug discovery and NMR identified PDZ1i, an inhibitor of the PDZ1 domain that effectively blocks cancer invasion in vitro and in vivo in multiple experimental animal models. To maximize disruption of MDA-9/Syntenin signaling, an inhibitor has now been developed that simultaneously binds and blocks activity of both PDZ domains. PDZ1i was joined to the second PDZ binding peptide (TNYYFV) with a PEG linker, resulting in PDZ1i/2i (IVMT-Rx-3) that engages both PDZ domains of MDA-9/Syntenin. IVMT-Rx-3 blocks MDA-9/Syntenin interaction with Src, reduces NF-κB activation, and inhibits MMP-2/MMP-9 expression, culminating in repression of melanoma metastasis. The in vivo antimetastatic properties of IVMT-Rx-3 are enhanced when combined with an immune-checkpoint inhibitor. Collectively, our results support the feasibility of engineering MDA-9 dual-PDZ inhibitors with enhanced antimetastatic activities and applications of IVMT-Rx-3 for developing novel therapeutic strategies effectively targeting melanoma and in principle, a broad spectrum of human cancers that also overexpress MDA-9/Syntenin.
Assuntos
Melanoma , Animais , Humanos , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/metabolismo , Sinteninas/química , Transdução de Sinais , Peptídeos/metabolismoRESUMO
melanoma differentiation associated gene-7 or Interleukin-24 (mda-7, IL-24) displays expansive anti-tumor activity without harming corresponding normal cells/tissues. This anticancer activity has been documented in vitro and in vivo in multiple preclinical animal models, as well as in patients with advanced cancers in a phase I clinical trial. To enhance the therapeutic efficacy of MDA-7 (IL-24), we engineered a designer cytokine (a "Superkine"; IL-24S; referred to as M7S) with enhanced secretion and increased stability to engender improved "bystander" antitumor effects. M7S was engineered in a two-step process by first replacing the endogenous secretory motif with an alternate secretory motif to boost secretion. Among four different signaling peptides, the insulin secretory motif significantly enhanced the secretion of MDA-7 (IL-24) protein and was chosen for M7S. The second modification engineered in M7S was designed to enhance the stability of MDA-7 (IL-24), which was accomplished by replacing lysine at position K122 with arginine. This engineered "M7S Superkine" with increased secretion and stability retained cancer specificity. Compared to parental MDA-7 (IL-24), M7S (IL-24S) was superior in promoting anti-tumor and bystander effects leading to improved outcomes in multiple cancer xenograft models. Additionally, combinatorial therapy using MDA-7 (IL-24) or M7S (IL-24S) with an immune checkpoint inhibitor, anti-PD-L1, dramatically reduced tumor progression in murine B16 melanoma cells. These results portend that M7S (IL-24S) promotes the re-emergence of an immunosuppressive tumor microenvironment, providing a solid rationale for prospective translational applications of this therapeutic designer cytokine.
RESUMO
Progression-elevated gene-3 (PEG-3) and rat growth arrest and DNA damage-inducible gene-34 (GADD34) display significant sequence homology with regulation predominantly transcriptional. The rat full-length (FL) and minimal (min) PEG-3 promoter display cancer-selective expression in rodent and human tumors, allowing for cancer-directed regulation of transgenes, viral replication and in vivo imaging of tumors and metastases in animals, whereas the FL- and min-GADD34-Prom lack cancer specificity. Min-PEG-Prom and min-GADD34-Prom have identical sequences except for two single-point mutation differences (at -260 bp and +159 bp). Engineering double mutations in the min-GADD34-Prom produce the GAPE-Prom. Changing one base pair (+159) or both point mutations in the min-GADD34-Prom, but not the FL-GADD34-Prom, results in cancer-selective transgene expression in diverse cancer cells (including prostate, breast, pancreatic and neuroblastoma) vs. normal counterparts. Additionally, we identified a GATA2 transcription factor binding site, promoting cancer specificity when both min-PEG-Prom mutations are present in the GAPE-Prom. Taken together, introducing specific point mutations in a rat min-GADD34-Prom converts this non-cancer-specific promoter into a cancer-selective promoter, and the addition of GATA2 with existing AP1 and PEA3 transcription factors enhances further cancer-selective activity of the GAPE-Prom. The GAPE-Prom provides a genetic tool to specifically regulate transgene expression in cancer cells.
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AIMS: SARI (suppressor of activator protein (AP)-1, regulated by interferon (IFN) was identified as a novel tumor suppressor by applying subtraction hybridization to terminally differentiating human melanoma cells. The anti-tumor activity of SARI and the correlation between expression and cancer aggression and metastasis has been examined in multiple cancers, but its potential role in oral squamous cell carcinomas (OSCC) has not been explored. METHODS: SARI expression was monitored in tumor tissues of OSCC patients by performing immunohistochemistry. Ectopic expression of SARI was achieved using a replication defective adenovirus expressing SARI (Ad.SARI). A nude mouse xenograft model was used to evaluate the in vivo efficacy of SARI. Endoplasmic reticulum (ER) stress was monitored in SARI infected OSCC cells by confocal microscopy. KEY FINDING: In this study, we demonstrate that SARI expression is significantly lower in OSCC tumor tissue as compared to normal adjacent tissue. Ectopic expression of SARI induces cancer-specific cell death in human OSCC cell lines and in a paclitaxel plus cisplatin non-responder OSCC patient-derived (PDC1) cell line. Mechanistically, SARI inhibits zinc finger protein GLI1 expression through induction of endoplasmic reticulum (ER) stress. Using a nude mouse xenograft model, we show that intratumoral injections of Ad.SARI significantly reduce PDC1 tumor burden, whereas treatment with an ER stress inhibitor efficiently rescues tumors from growth inhibition. SIGNIFICANCE: Overall, our data provides a link between induction of ER stress and inhibition of the GLI1/Hedgehog signaling pathway and the tumor suppressive activity of SARI in the context of OSCC.
Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/biossíntese , Carcinoma de Células Escamosas/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , Inibidores do Crescimento/biossíntese , Neoplasias Bucais/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Proteínas Supressoras de Tumor/biossíntese , Animais , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/fisiologia , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Bucais/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodosRESUMO
Melanoma differentiation associated gene-9 (MDA-9), Syntenin-1, or syndecan binding protein is a differentially regulated prometastatic gene with elevated expression in advanced stages of melanoma. MDA-9/Syntenin expression positively associates with advanced disease stage in multiple histologically distinct cancers and negatively correlates with patient survival and response to chemotherapy. MDA-9/Syntenin is a highly conserved PDZ-domain scaffold protein, robustly expressed in a spectrum of diverse cancer cell lines and clinical samples. PDZ domains interact with a number of proteins, many of which are critical regulators of signaling cascades in cancer. Knockdown of MDA-9/Syntenin decreases cancer cell metastasis, sensitizing these cells to radiation. Genetic silencing of MDA-9/Syntenin or treatment with a pharmacological inhibitor of the PDZ1 domain, PDZ1i, also activates the immune system to kill cancer cells. Additionally, suppression of MDA-9/Syntenin deregulates myeloid-derived suppressor cell differentiation via the STAT3/interleukin (IL)-1ß pathway, which concomitantly promotes activation of cytotoxic T lymphocytes. Biologically, PDZ1i treatment decreases metastatic nodule formation in the lungs, resulting in significantly fewer invasive cancer cells. In summary, our observations indicate that MDA-9/Syntenin provides a direct therapeutic target for mitigating aggressive breast cancer and a small-molecule inhibitor, PDZ1i, provides a promising reagent for inhibiting advanced breast cancer pathogenesis.
Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Interleucina-1beta/genética , Neoplasias Pulmonares/tratamento farmacológico , Oxidiazóis/farmacologia , Pirimidinas/farmacologia , Sinteninas/genética , Animais , Antineoplásicos/síntese química , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Quimiocina CCL11/genética , Quimiocina CCL11/imunologia , Quimiocina CCL17/genética , Quimiocina CCL17/imunologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Interleucina-10/genética , Interleucina-10/imunologia , Interleucina-1alfa/genética , Interleucina-1alfa/imunologia , Interleucina-1beta/antagonistas & inibidores , Interleucina-1beta/imunologia , Subunidade p19 da Interleucina-23/genética , Subunidade p19 da Interleucina-23/imunologia , Interleucina-5/genética , Interleucina-5/imunologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Endogâmicos BALB C , Oxidiazóis/síntese química , Pirimidinas/síntese química , Transdução de Sinais , Sinteninas/antagonistas & inibidores , Sinteninas/imunologia , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/patologia , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Combining cancer-selective viral replication and simultaneous production of a therapeutic cytokine, with potent "bystander" anti-tumor activity, are hallmarks of the cancer terminator virus (CTV). To expand on these attributes, we designed a next generation CTV that additionally enables simultaneous non-invasive imaging of tumors targeted for eradication. A unique tripartite CTV "theranostic" adenovirus (TCTV) has now been created that employs three distinct promoters to target virus replication, cytokine production and imaging capabilities uniquely in cancer cells. Conditional replication of the TCTV is regulated by a cancer-selective (truncated PEG-3) promoter, the therapeutic component, MDA-7/IL-24, is under a ubiquitous (CMV) promoter, and finally the imaging capabilities are synchronized through another cancer selective (truncated tCCN1) promoter. Using in vitro studies and clinically relevant in vivo models of breast and prostate cancer, we demonstrate that incorporating a reporter gene for imaging does not compromise the exceptional therapeutic efficacy of our previously reported bipartite CTV. This TCTV permits targeted treatment of tumors while monitoring tumor regression, with potential to simultaneously detect metastasis due to the cancer-selective activity of reporter gene expression. This "theranostic" virus provides a new genetic tool for distinguishing and treating localized and metastatic cancers.
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Melanoma differentiation associated gene-7/interleukin-24 (MDA-7/IL-24), a secreted protein of the IL-10 family, was first identified more than two decades ago as a novel gene differentially expressed in terminally differentiating human metastatic melanoma cells. MDA-7/IL-24 functions as a potent tumor suppressor exerting a diverse array of functions including the inhibition of tumor growth, invasion, angiogenesis, and metastasis, and induction of potent "bystander" antitumor activity and synergy with conventional cancer therapeutics. MDA-7/IL-24 induces cancer-specific cell death through apoptosis or toxic autophagy, which was initially established in vitro and in preclinical animal models in vivo and later in a Phase I clinical trial in patients with advanced cancers. This review summarizes the history and our current understanding of the molecular/biological mechanisms of MDA-7/IL-24 action rendering it a potent cancer suppressor.
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Interleucinas/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Apoptose/fisiologia , Autofagia/fisiologia , Morte Celular/fisiologia , Humanos , Melanoma/metabolismoRESUMO
Glioblastoma multiforme (GBM) is an aggressive cancer without currently effective therapies. Radiation and temozolomide (radio/TMZ) resistance are major contributors to cancer recurrence and failed GBM therapy. Heat shock proteins (HSPs), through regulation of extracellular matrix (ECM) remodeling and epithelial mesenchymal transition (EMT), provide mechanistic pathways contributing to the development of GBM and radio/TMZ-resistant GBM. The Friend leukemia integration 1 (Fli-1) signaling network has been implicated in oncogenesis in GBM, making it an appealing target for advancing novel therapeutics. Fli-1 is linked to oncogenic transformation with up-regulation in radio/TMZ-resistant GBM, transcriptionally regulating HSPB1. This link led us to search for targeted molecules that inhibit Fli-1. Expression screening for Fli-1 inhibitors identified lumefantrine, an antimalarial drug, as a probable Fli-1 inhibitor. Docking and isothermal calorimetry titration confirmed interaction between lumefantrine and Fli-1. Lumefantrine promoted growth suppression and apoptosis in vitro in parental and radio/TMZ-resistant GBM and inhibited tumor growth without toxicity in vivo in U87MG GBM and radio/TMZ-resistant GBM orthotopic tumor models. These data reveal that lumefantrine, an FDA-approved drug, represents a potential GBM therapeutic that functions through inhibition of the Fli-1/HSPB1/EMT/ECM remodeling protein networks.
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Antimaláricos/administração & dosagem , Antineoplásicos Alquilantes/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Lumefantrina/administração & dosagem , Temozolomida/administração & dosagem , Neoplasias Encefálicas/radioterapia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/radioterapia , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Transativadores/genética , Transativadores/metabolismoRESUMO
Tumor metastasis comprises a series of coordinated events that culminate in dissemination of cancer cells to distant sites within the body representing the greatest challenge impeding effective therapy of cancer and the leading cause of cancer-associated morbidity. Cancer cells exploit multiple genes and pathways to colonize to distant organs. These pathways are integrated and regulated at different levels by cellular- and extracellular-associated factors. Defining the genes and pathways that govern metastasis can provide new targets for therapeutic intervention. Melanoma differentiation associated gene-9 (mda-9) (also known as Syntenin-1 and SDCBP (Syndecan binding protein)) was identified by subtraction hybridization as a novel gene displaying differential temporal expression during differentiation of melanoma. MDA-9/Syntenin is an established Syndecan binding protein that functions as an adaptor protein. Expression of MDA-9/Syntenin is elevated at an RNA and protein level in a wide-range of cancers including melanoma, glioblastoma, neuroblastoma, and prostate, breast and liver cancer. Expression is increased significantly in metastatic cancer cells as compared with non-metastatic cancer cells or normal cells, which make it an attractive target in treating cancer metastasis. In this review, we focus on the role and regulation of mda-9 in cancer progression and metastasis.
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Neoplasias/metabolismo , Sinteninas/metabolismo , Animais , Humanos , Metástase Neoplásica , Neoplasias/genética , Neoplasias/patologia , Sinteninas/genéticaRESUMO
The primary cause of cancer-related death from solid tumors is metastasis. While unraveling the mechanisms of this complicated process continues, our ability to effectively target and treat it to decrease patient morbidity and mortality remains disappointing. Early detection of metastatic lesions and approaches to treat metastases (both pharmacological and genetic) are of prime importance to obstruct this process clinically. Metastasis is complex involving both genetic and epigenetic changes in the constantly evolving tumor cell. Moreover, many discrete steps have been identified in metastatic spread, including invasion, intravasation, angiogenesis, attachment at a distant site (secondary seeding), extravasation and micrometastasis and tumor dormancy development. Here, we provide an overview of the metastatic process and highlight a unique pro-metastatic gene, melanoma differentiation associated gene-9/Syntenin (MDA-9/Syntenin) also called syndecan binding protein (SDCBP), which is a major contributor to the majority of independent metastatic events. MDA-9 expression is elevated in a wide range of carcinomas and other cancers, including melanoma, glioblastoma multiforme and neuroblastoma, suggesting that it may provide an appropriate target to intervene in metastasis. Pre-clinical studies confirm that inhibiting MDA-9 either genetically or pharmacologically profoundly suppresses metastasis. An additional benefit to blocking MDA-9 in metastatic cells is sensitization of these cells to a second therapeutic agent, which converts anti-invasion effects to tumor cytocidal effects. Continued mechanistic and therapeutic insights hold promise to advance development of truly effective therapies for metastasis in the future.
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Metástase Neoplásica/genética , Neoplasias/terapia , Sinteninas/genética , Animais , Humanos , Neoplasias/genética , Neoplasias/patologiaRESUMO
Metastasis is the primary determinant of death in patients with diverse solid tumors and MDA-9/Syntenin (SDCBP), a pro-metastatic and pro-angiogenic gene, contributes to this process. Recently, we documented that by physically interacting with IGF-1R, MDA-9/Syntenin activates STAT3 and regulates prostate cancer pathogenesis. These observations firmly established MDA-9/Syntenin as a potential molecular target in prostate cancer. MDA-9/Syntenin contains two highly homologous PDZ domains predicted to interact with a plethora of proteins, many of which are central to the cancerous process. An MDA-9/Syntenin PDZ1 domain-targeted small molecule (PDZ1i) was previously developed using fragment-based drug discovery (FBDD) guided by NMR spectroscopy and was found to be well-tolerated in vivo, had significant half-life (t 1/2 = 9 hours) and displayed substantial anti-prostate cancer preclinical in vivo activity. PDZ1i blocked tumor cell invasion and migration in vitro, and metastasis in vivo Hence, we demonstrate that PDZ1i an MDA-9/Syntenin PDZ1 target-specific small-molecule inhibitor displays therapeutic potential for prostate and potentially other cancers expressing elevated levels of MDA-9/Syntenin.
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Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/secundário , Neoplasias da Próstata/tratamento farmacológico , Bibliotecas de Moléculas Pequenas/administração & dosagem , Sinteninas/química , Animais , Sítios de Ligação/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Humanos , Masculino , Camundongos , Domínios Proteicos , Receptor IGF Tipo 1/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Sinteninas/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Cisplatin alone or in combination with 5FU (5-fluorouracil) and docetaxel (TPF) are common regimen chemotherapeutics for treatment of advanced oral squamous cell carcinoma (OSCC). Despite the initial positive response, several patients experience relapse due to chemoresistance. The potential role of Bcl-2 antiapoptotic members in acquired chemoresistance is yet to be explored. To address this, we designed two different relevant OSCC chemoresistant models: (i) acquired chemoresistant cells, where OSCC lines were treated with conventional chemotherapy for a prolonged period to develop chemoresistance, and (ii) chemoresistant patient-derived cells, where primary cells were established from tumor of neoadjuvant-treated OSCC patients who do not respond to TPF. Among all Bcl-2 antiapoptotic members, Mcl-1 expression (but not Bcl-2 or Bcl-xL) was found to be upregulated in both chemoresistant OSCC lines and chemoresistant tumors when compared with their respective sensitive counterparts. Irrespective of all three chemotherapy drugs, Mcl-1 expression was elevated in OSCC cells that are resistant to either cisplatin or 5FU or docetaxel. In chemoresistant OSCC, Mcl-1 mRNA was upregulated by signal transducer and activator of transcription 3 (STAT3) activation, and the protein was stabilized by AKT-mediated glycogen synthase kinase 3 beta (GSK3ß) inactivation. Genetic (siRNA) or pharmacological (Triptolide, a transcriptional repressor of Mcl-1) inhibition of Mcl-1 induces drug-mediated cell death in chemoresistant OSCC. In patient-derived xenograft model of advanced stage and chemoresistant OSCC tumor, Triptolide restores cisplatin-mediated cell death and facilitates significant reduction of tumor burdens. Overall, our data suggest Mcl-1 dependency of chemoresistant OSCC. A combination regimen of Mcl-1 inhibitor with conventional chemotherapy deserves further clinical investigation in advanced OSCC.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Glicogênio Sintase Quinase 3 beta/fisiologia , Neoplasias Bucais/tratamento farmacológico , Proteína de Sequência 1 de Leucemia de Células Mieloides/fisiologia , Fator de Transcrição STAT3/fisiologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Diterpenos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Compostos de Epóxi/farmacologia , Fluoruracila/uso terapêutico , Humanos , Masculino , Camundongos , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Fenantrenos/farmacologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Taxoides/uso terapêuticoRESUMO
Cancer is a daunting global problem confronting the world's population. The most frequent therapeutic approaches include surgery, chemotherapy, radiotherapy, and more recently immunotherapy. In the case of chemotherapy, patients ultimately develop resistance to both single and multiple chemotherapeutic agents, which can culminate in metastatic disease which is a major cause of patient death from solid tumors. Chemoresistance, a primary cause of treatment failure, is attributed to multiple factors including decreased drug accumulation, reduced drug-target interactions, increased populations of cancer stem cells, enhanced autophagy activity, and reduced apoptosis in cancer cells. Reprogramming tumor cells to undergo drug-induced apoptosis provides a promising and powerful strategy for treating resistant and recurrent neoplastic diseases. This can be achieved by downregulating dysregulated antiapoptotic factors or activation of proapoptotic factors in tumor cells. A major target of dysregulation in cancer cells that can occur during chemoresistance involves altered expression of Bcl-2 family members. Bcl-2 antiapoptotic molecules (Bcl-2, Bcl-xL, and Mcl-1) are frequently upregulated in acquired chemoresistant cancer cells, which block drug-induced apoptosis. We presently overview the potential role of Bcl-2 antiapoptotic proteins in the development of cancer chemoresistance and overview the clinical approaches that use Bcl-2 inhibitors to restore cell death in chemoresistant and recurrent tumors.
Assuntos
Antineoplásicos/farmacologia , Apoptose , Autofagia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Animais , Humanos , Neoplasias/metabolismo , Neoplasias/patologiaRESUMO
Here, a facile one-step approach has been developed for the synthesis of carbon quantum dots (CQDs) from Good's buffer. The as-synthesized CQDs emit a bright greenish blue coloured fluorescence after exposure to a 365 nm UV-lamp illumination. The bright fluorescence nature of the CQDs has proven them to be excellent probes for cellular imaging. The CQDs are highly biocompatible in nature, which has been validated by an MTT assay test. The in vitro MTT assay demonstrates a more than 95% survival rate when HEK293 (human embryonic kidney) and H357 (human oral squamous carcinoma) cells were treated with CQDs. The low cytotoxicity of Good's buffer derived CQDs opens the door to biomedical applications. The anticancer drug doxorubicin (DOX) was successfully loaded on the CQDs and their delivery efficiency to the target cells via in vitro treatment of cancerous cells was explored. The CQDs supported DOX showed a higher killing rate of the cancer cells compared to bare DOX due to its ease of internalization and efficient pH-triggered release inside the cells.
RESUMO
Oral and oropharyngeal cancers are the sixth most common cancers worldwide. Despite intensive investigation, oral squamous cell carcinomas (OSCC) represent a clinical challenge resulting in significant morbidity and mortality. Resistance to cell death is common in OSCC and is often mediated by the Bcl-2 family proteins. Among all anti-apoptotic Bcl-2 family members, Mcl-1 functions as a major survival factor, particularly in solid cancers. Despite the confirmed importance of Mcl-1 in several neoplasms, the role of Mcl-1 in OSCC survival has yet to be explored. In this study, we found that knocking down Mcl-1 sensitized OSCC cells to ABT-737, which binds to Bcl-2/Bcl-xL but not Mcl-1. We report for the first time that a BH3 mimetic, Sabutoclax, which functions as an inhibitor of all anti-apoptotic Bcl-2 proteins, induced cancer-specific cell death in an Mcl-1-dependent manner through both apoptosis and toxic mitophagy. In vivo studies demonstrated that Sabutoclax alone decreased tumor growth in a carcinogen-induced tongue OSCC mouse model. In a combination regimen, Sabutoclax and COX-2 inhibitor, Celecoxib, synergistically inhibited the growth of OSCC in vitro and also significantly reduced OSCC tumor growth in vivo. Overall, these results identify Mcl-1 as a therapeutic prospective target in OSCC.
Assuntos
Compostos de Bifenilo/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Celecoxib/farmacologia , Gossipol/análogos & derivados , Neoplasias Bucais/tratamento farmacológico , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Nitrofenóis/farmacologia , Sulfonamidas/farmacologia , 4-Nitroquinolina-1-Óxido/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/genética , Proteína 5 Relacionada à Autofagia , Proteína 7 Relacionada à Autofagia , Proteína Beclina-1 , Linhagem Celular Tumoral , Inibidores de Ciclo-Oxigenase 2/farmacologia , Feminino , Gossipol/farmacologia , Humanos , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Associadas aos Microtúbulos/genética , Mitofagia/efeitos dos fármacos , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas/genética , Quinolonas/farmacologia , Interferência de RNA , RNA Interferente Pequeno , Distribuição Aleatória , Enzimas Ativadoras de Ubiquitina/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína bcl-X/antagonistas & inibidoresRESUMO
The Kaposi's sarcoma-associated herpesvirus infects the human population and maintains latency stage of viral life cycle in a variety of cell types including cells of epithelial, mesenchymal and endothelial origin. The establishment of latent infection by KSHV requires the expression of an unique repertoire of genes among which latency associated nuclear antigen (LANA) plays a critical role in the replication of the viral genome. LANA regulates the transcription of a number of viral and cellular genes essential for the survival of the virus in the host cell. The present study demonstrates the disruption of the host G2/M cell cycle checkpoint regulation as an associated function of LANA. DNA profile of LANA expressing human B-cells demonstrated the ability of this nuclear antigen in relieving the drug (Nocodazole) induced G2/M checkpoint arrest. Caffeine suppressed nocodazole induced G2/M arrest indicating involvement of the ATM/ATR. Notably, we have also shown the direct interaction of LANA with Chk2, the ATM/ATR signalling effector and is responsible for the release of the G2/M cell cycle block.