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BACKGROUND: Using a human-centered design (HCD) approach can provide clinical trial design teams with a better understanding of the needs, preferences, and attitudes of clinical trial stakeholders. It can also be used to understand the challenges and barriers physician stakeholders face in initiating and completing clinical trials, especially for using off-label drugs (OLDs) to treat unmet clinical needs in cancer treatment. However, the HCD approach is not commonly taught in the context of clinical trial design, and few step-by-step guides similar to this study are available to demonstrate its application. OBJECTIVE: This study aims to demonstrate the feasibility and process of applying an HCD approach to creating clinical trial support resources for physician stakeholders to overcome barriers to pursuing clinical trials for OLDs to treat cancer. METHODS: An HCD approach was used to develop OLD clinical trial support concepts. In total, 45 cancer care physicians were contacted, of which 15 participated in semistructured interviews to identify barriers to prescribing OLDs or participating in cancer OLD clinical trials. Design research is qualitative-it seeks to answer "why" and "how" questions; thus, a sample size of 15 was sufficient to provide insight saturation to address the design problem. The team used affinity mapping and thematic analysis of qualitative data gathered from the interviews to inform subsequent web-based co-design sessions, which included creative matrix exercises and voting to refine and prioritize the ideas used in the final 3 recommended concepts. RESULTS: The findings demonstrate the potential of HCD methods to uncover important insights into the barriers physicians face in participating in OLD clinical trials or prescribing OLDs, such as recruitment challenges, low willingness to prescribe without clinical data, and stigma. Notably, only palliative care participants self-identified as "frequent prescribers" of OLDs, despite high national OLD prescription rates among patients with cancer. Participants found the HCD approach engaging, with 60% (9/15) completing this study; scheduling conflicts caused most of the dropouts. Over 150 ideas were generated in 3 co-design sessions, with the groups voting on 15 priority ideas that the design team then refined into 3 final recommendations, especially focused on increasing the participation of physicians in OLD clinical trials. CONCLUSIONS: Using participatory HCD methods, we delivered 3 concepts for clinical trial support resources to help physician stakeholders overcome barriers to pursuing clinical trials for OLDs to treat cancer. Overall, integrating the HCD approach can aid in identifying important stakeholders, such as prescribing physicians; facilitating their engagement; and incorporating their perspectives and needs into the solution design process. This paper highlights the process, methods, and potential of HCD to improve cancer clinical trial design. Future work is needed to train clinical trial designers in the HCD approach and encourage adoption in the field.
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A major cause of cancer recurrence following chemotherapy is cancer dormancy escape. Taxane-based chemotherapy is standard of care in breast cancer treatment aimed at killing proliferating cancer cells. Here, we demonstrate that docetaxel injures stromal cells, which release protumor cytokines, IL-6 and granulocyte colony stimulating factor (G-CSF), that in turn invoke dormant cancer outgrowth both in vitro and in vivo. Single-cell transcriptomics shows a reprogramming of awakened cancer cells including several survival cues such as stemness, chemoresistance in a tumor stromal organoid (TSO) model, as well as an altered tumor microenvironment (TME) with augmented protumor immune signaling in a syngeneic mouse breast cancer model. IL-6 plays a role in cancer cell proliferation, whereas G-CSF mediates tumor immunosuppression. Pathways and differential expression analyses confirmed MEK as the key regulatory molecule in cancer cell outgrowth and survival. Antibody targeting of protumor cytokines (IL-6, G-CSF) or inhibition of cytokine signaling via MEK/ERK pathway using selumetinib prior to docetaxel treatment prevented cancer dormancy outgrowth suggesting a novel therapeutic strategy to prevent cancer recurrence.
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Interleucina-6 , Neoplasias , Animais , Camundongos , Docetaxel/farmacologia , Taxoides/farmacologia , Taxoides/uso terapêutico , Citocinas , Fator Estimulador de Colônias de Granulócitos , Quinases de Proteína Quinase Ativadas por MitógenoRESUMO
BACKGROUND: Immune checkpoint inhibitors (ICI) are commonly used in the management of patients with advanced non-small cell lung cancer (NSCLC), but response is suboptimal. Preclinical data suggest ICI efficacy may be enhanced with concomitant nonsteroidal anti-inflammatory (NSAID) medications. PATIENTS AND METHODS: In this retrospective study, the Veterans Health Administration Corporate Data Warehouse was queried for patients diagnosed with NSCLC and treated with ICI from 2010 to 2018. Concomitant NSAID use was defined as NSAID dispensation by a VA pharmacy within 90 days of the any ICI infusion. To mitigate immortal time bias, patients who started NSAIDs 60 or more days after ICI initiation were excluded from analysis. Survival was measured from start of ICI. RESULTS: We identified 3634 patients with NSCLC receiving ICI; 2336 (64.3%) were exposed to concomitant NSAIDs. On multivariable analysis, NSAIDs were associated with better overall survival (HR = 0.90; 95% CI, 0.83-0.98; P = .010). When stratifying by NSAID type, diclofenac was the only NSAID with significant association with overall survival (HR = 0.75; 95% CI, 0.68-0.83; P < .001). Propensity score matching of the original cohort yielded 1251 patients per cohort balanced in characteristics. NSAIDs remained associated with improved overall survival (HR = 0.85; 95% CI, 0.78-0.92; P < .001). CONCLUSION: This study of Veterans with NSCLC treated with ICI demonstrated that concomitant NSAIDs are associated with longer OS. This may indicate that NSAIDs can enhance ICI-induced antitumor immunity and should prospectively validated.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Anti-Inflamatórios não Esteroides/uso terapêutico , Inibidores de Checkpoint Imunológico/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Estudos Retrospectivos , Neoplasias Pulmonares/tratamento farmacológicoRESUMO
BACKGROUND: Peroxisome proliferator-activated receptor agonists such as fibrates restore oxidative metabolism in cytotoxic T-lymphocytes, thereby enhancing response to immune checkpoint inhibitors (ICI) in preclinical models. However, there is no evidence in humans on the clinical impact of fibrates as an adjunct to ICI. METHODS: In this cohort study of Veterans with non-small cell lung cancer (NSCLC) receiving ICI, fibrate exposure was defined as a prescription filled within 90 days of an ICI infusion. Overall survival (OS), measured from the start of ICI, was compared between exposed and unexposed Veterans. Cox multivariable analysis (MVA) was used to identify factors associated with OS. A sensitivity analysis of Veterans with stage IV NSCLC who received docetaxel without ICI was similarly performed. RESULTS: The ICI cohort included 3593 Veterans, of whom 301 (8.5%) coincidentally received a fibrate. Veterans receiving fibrates were more likely to be older, white, male, and married, and to have greater comorbidity burden, but less likely to receive chemotherapy. Coincidental fibrates were associated with improved OS both on MVA (HR 0.86, 95%CI 0.75-0.99) and in a matched subset (HR 0.75, 95%CI 0.63-0.90). In contrast, among the cohort of 968 Veterans treated with chemotherapy, fibrates did not have a significant impact on OS by MVA (HR 0.99, 95%CI 0.79-1.25) or in a matched subset (HR 1.02, 95%CI CI 0.75-1.39). CONCLUSIONS: Concomitant fibrates are associated with improved OS among NSCLC patients receiving ICI but not among those receiving chemotherapy. This hypothesis-generating observation supports a potential role for fibrates as an adjunct to immunotherapy.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Masculino , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Estudos de Coortes , Neoplasias Pulmonares/tratamento farmacológico , Imunoterapia , Ácidos Fíbricos/uso terapêutico , Estudos RetrospectivosRESUMO
To improve the efficacy of immune checkpoint inhibitors (ICIs) for cancer treatment, various strategies, including combination therapies with repurposed drugs, are being explored. Several readily available interventions with potential to enhance programmed death 1 (PD-1) blockade have been identified. However, these interventions often remain overlooked due to the lack of financial incentives for their development, making them financial orphans. This review summarizes current knowledge regarding off-label drugs, supplements, and other readily available interventions that could improve the efficacy of PD-1 blockade. The summary of each intervention includes the proposed mechanism of action for combination with checkpoint inhibitors and data from animal and human studies. Additionally, we include summaries of common interventions to be avoided by patients on PD-1 blockade. Finally, we present approaches for conducting further studies in patients, with the aim of expediting the clinical development of these interventions. We strive to increase awareness of readily available combination therapies that may advance cancer immunotherapy and help patients today.
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Inibidores de Checkpoint Imunológico , Neoplasias , Animais , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Receptor de Morte Celular Programada 1 , Neoplasias/tratamento farmacológico , Terapia CombinadaRESUMO
Fluvoxamine is a well-tolerated, widely available, inexpensive selective serotonin reuptake inhibitor that has been shown in a small, double-blind, placebo-controlled, randomized study to prevent clinical deterioration of patients with mild coronavirus disease 2019 (COVID-19). Fluvoxamine is also an agonist for the sigma-1 receptor, through which it controls inflammation. We review here a body of literature that shows important mechanisms of action of fluvoxamine and other SSRIs that could play a role in COVID-19 treatment. These effects include: reduction in platelet aggregation, decreased mast cell degranulation, interference with endolysosomal viral trafficking, regulation of inositol-requiring enzyme 1α-driven inflammation and increased melatonin levels, which collectively have a direct antiviral effect, regulate coagulopathy or mitigate cytokine storm, which are known hallmarks of severe COVID-19.
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Tratamento Farmacológico da COVID-19 , Reposicionamento de Medicamentos/tendências , SARS-CoV-2/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/uso terapêutico , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/química , Monofosfato de Adenosina/farmacocinética , Monofosfato de Adenosina/uso terapêutico , Alanina/análogos & derivados , Alanina/química , Alanina/farmacocinética , Alanina/uso terapêutico , Animais , COVID-19/sangue , COVID-19/virologia , Modelos Animais de Doenças , Flavonoides/química , Flavonoides/farmacocinética , Flavonoides/uso terapêutico , Humanos , Camundongos , Nitrocompostos/química , Nitrocompostos/farmacocinética , Nitrocompostos/uso terapêutico , Preparações Farmacêuticas , SARS-CoV-2/patogenicidade , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacocinética , Teicoplanina/análogos & derivados , Teicoplanina/química , Teicoplanina/farmacocinética , Teicoplanina/uso terapêutico , Tiazóis/química , Tiazóis/farmacocinética , Tiazóis/uso terapêuticoAssuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Reposicionamento de Medicamentos , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/cirurgia , Intervalo Livre de Doença , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Metástase NeoplásicaRESUMO
Cancer therapy is a double-edged sword, as surgery and chemotherapy can induce an inflammatory/immunosuppressive injury response that promotes dormancy escape and tumor recurrence. We hypothesized that these events could be altered by early blockade of the inflammatory cascade and/or by accelerating the resolution of inflammation. Preoperative, but not postoperative, administration of the nonsteroidal antiinflammatory drug ketorolac and/or resolvins, a family of specialized proresolving autacoid mediators, eliminated micrometastases in multiple tumor-resection models, resulting in long-term survival. Ketorolac unleashed anticancer T cell immunity that was augmented by immune checkpoint blockade, negated by adjuvant chemotherapy, and dependent on inhibition of the COX-1/thromboxane A2 (TXA2) pathway. Preoperative stimulation of inflammation resolution via resolvins (RvD2, RvD3, and RvD4) inhibited metastases and induced T cell responses. Ketorolac and resolvins exhibited synergistic antitumor activity and prevented surgery- or chemotherapy-induced dormancy escape. Thus, simultaneously blocking the ensuing proinflammatory response and activating endogenous resolution programs before surgery may eliminate micrometastases and reduce tumor recurrence.
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Ácidos Docosa-Hexaenoicos/farmacologia , Imunidade Celular/efeitos dos fármacos , Cetorolaco/farmacologia , Recidiva Local de Neoplasia/prevenção & controle , Neoplasias Experimentais , Cuidados Pré-Operatórios , Linfócitos T/metabolismo , Animais , Masculino , Camundongos , Camundongos Knockout , Metástase Neoplásica , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Neoplasias Experimentais/terapia , Linfócitos T/patologiaRESUMO
There has been a major resurgence of interest in immune-based approaches to treat cancer, based largely on the success of checkpoint inhibitors (anti-cytotoxic T-lymphocyte-associated antigen 4, anti-programmed cell death 1, and anti-programmed cell death ligand 1 antibodies) in several malignancies. However, not all tumors respond to checkpoint therapy, and there is clearly a need for additional approaches for enhancing tumor immunity. We summarize the critical elements necessary for mounting an efficacious T-cell response to a tumor. We cite drugs approved by the Food and Drug Administration for no-cancer indications that could be repurposed and used as part of an antitumor immune cocktail. We also list cancer drugs not initially intended to impact tumor immunity (soft repurposing) but that have been found to modulate the immune system. We highlight those drugs that might be used in combination with checkpoint inhibitors to increase response rates and survival of cancer patients. Our focus will be on drugs for which there are limited but existing human data. We cite supporting mechanistic mouse data as well. Repurposing drugs to modulate antitumor immunity is an opportunity to rapidly bring new, effective, and affordable treatments to cancer patients.
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Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Humanos , Estados Unidos , United States Food and Drug AdministrationRESUMO
Inflammation in the tumor microenvironment is a strong promoter of tumor growth. Substantial epidemiologic evidence suggests that aspirin, which suppresses inflammation, reduces the risk of cancer. The mechanism by which aspirin inhibits cancer has remained unclear, and toxicity has limited its clinical use. Aspirin not only blocks the biosynthesis of prostaglandins, but also stimulates the endogenous production of anti-inflammatory and proresolving mediators termed aspirin-triggered specialized proresolving mediators (AT-SPMs), such as aspirin-triggered resolvins (AT-RvDs) and lipoxins (AT-LXs). Using genetic and pharmacologic manipulation of a proresolving receptor, we demonstrate that AT-RvDs mediate the antitumor activity of aspirin. Moreover, treatment of mice with AT-RvDs (e.g., AT-RvD1 and AT-RvD3) or AT-LXA4 inhibited primary tumor growth by enhancing macrophage phagocytosis of tumor cell debris and counter-regulating macrophage-secreted proinflammatory cytokines, including migration inhibitory factor, plasminogen activator inhibitor-1, and C-C motif chemokine ligand 2/monocyte chemoattractant protein 1. Thus, the pro-resolution activity of AT-resolvins and AT-lipoxins may explain some of aspirin's broad anticancer activity. These AT-SPMs are active at considerably lower concentrations than aspirin, and thus may provide a nontoxic approach to harnessing aspirin's anticancer activity.
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Antineoplásicos/farmacologia , Aspirina/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/prevenção & controle , Animais , Aspirina/administração & dosagem , Quimiocina CCL2/metabolismo , Quimiocinas/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Ácidos Docosa-Hexaenoicos/metabolismo , Eicosanoides/metabolismo , Ácidos Graxos Insaturados/metabolismo , Feminino , Inflamação/tratamento farmacológico , Lipoxinas/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Metabolômica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Proteínas Associadas aos Microtúbulos/metabolismo , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/prevenção & controle , Proteínas do Tecido Nervoso/metabolismo , Fagocitose/efeitos dos fármacos , Inativadores de Plasminogênio/metabolismo , Prostaglandinas/metabolismoRESUMO
Although chemotherapy is a conventional cancer treatment, it may induce a protumorigenic microenvironment by triggering the release of proinflammatory mediators. In this study, we demonstrate that ovarian tumor cell debris generated by first-line platinum- and taxane-based chemotherapy accelerates tumor progression by stimulating a macrophage-derived "surge" of proinflammatory cytokines and bioactive lipids. Thus, targeting a single inflammatory mediator or pathway is unlikely to prevent therapy-induced tumor progression. Here, we show that combined pharmacological abrogation of the cyclooxygenase-2 (COX-2) and soluble epoxide hydrolase (sEH) pathways prevented the debris-induced surge of both cytokines and lipid mediators by macrophages. In animal models, the dual COX-2/sEH inhibitor PTUPB delayed the onset of debris-stimulated ovarian tumor growth and ascites leading to sustained survival over 120 days postinjection. Therefore, dual inhibition of COX-2/sEH may be an approach to suppress debris-stimulated ovarian tumor growth by preventing the therapy-induced surge of cytokines and lipid mediators.
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Antineoplásicos/efeitos adversos , Antineoplásicos/farmacologia , Inibidores de Ciclo-Oxigenase 2/farmacologia , Ciclo-Oxigenase 2/metabolismo , Citocinas/metabolismo , Epóxido Hidrolases/antagonistas & inibidores , Neoplasias Ovarianas/tratamento farmacológico , Animais , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Carcinoma Epitelial do Ovário/tratamento farmacológico , Carcinoma Epitelial do Ovário/metabolismo , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Progressão da Doença , Feminino , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Lipídeos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos SCID , Neoplasias Ovarianas/metabolismo , Platina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Taxoides/farmacologiaRESUMO
Colon cancer recurrence after therapy, such as 5-fluorouracil (5-FU), remains a challenge in the clinical setting. Chemotherapy reduces tumor burden by inducing cell death; however, the resulting dead tumor cells, or debris, may paradoxically stimulate angiogenesis, inflammation, and tumor growth. Here, we demonstrate that 5-FU-generated colon carcinoma debris stimulates the growth of a subthreshold inoculum of living tumor cells in subcutaneous and orthotopic models. Debris triggered the release of osteopontin (OPN) by tumor cells and host macrophages. Both coinjection of debris and systemic treatment with 5-FU increased plasma OPN levels in tumor-bearing mice. RNA expression levels of secreted phosphoprotein 1, the gene that encodes OPN, correlate with poor prognosis in patients with colorectal cancer and are elevated in chemotherapy-treated patients who experience tumor recurrence vs. no recurrence. Pharmacologic and genetic ablation of OPN inhibited debris-stimulated tumor growth. Systemic treatment with a combination of a neutralizing OPN antibody and 5-FU dramatically inhibited tumor growth. These results demonstrate a novel mechanism of tumor progression mediated by OPN released in response to chemotherapy-generated tumor cell debris. Neutralization of debris-stimulated OPN represents a potential therapeutic strategy to overcome the inherent limitation of cytotoxic therapies as a result of the generation of cell debris.-Chang, J., Bhasin, S. S., Bielenberg, D. R., Sukhatme, V. P., Bhasin, M., Huang, S., Kieran, M. W., Panigrahy, D. Chemotherapy-generated cell debris stimulates colon carcinoma tumor growth via osteopontin.
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Neoplasias do Colo/patologia , Fluoruracila/farmacologia , Neovascularização Patológica/patologia , Osteopontina/metabolismo , Animais , Antimetabólitos Antineoplásicos/farmacologia , Apoptose , Proliferação de Células , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Selective phosphodiesterase 5 inhibitors, including sildenafil, tadalafil and vardenafil, are widely-used in the treatment of erectile dysfunction and pulmonary arterial hypertension. They are also well-known as examples of successful drug repurposing in that they were initially developed for angina and only later developed for erectile dysfunction. However, these drugs may also be effective cancer treatments. A range of evidentiary sources are assessed in this paper and the case made that there is pre-clinical and clinical evidence that these drugs may offer clinical benefit in a range of cancers. In particular, evidence is presented that these drugs have potent immunomodulatory activity that warrants clinical study in combination with check-point inhibition.
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Repurposing is a drug development strategy that seeks to use existing medications for new indications. In oncology, there is an increased level of activity looking at the use of non-cancer drugs as possible cancer treatments. The Repurposing Drugs in Oncology (ReDO) project has used a literature-based approach to identify licensed non-cancer drugs with published evidence of anticancer activity. Data from 268 drugs have been included in a database (ReDO_DB) developed by the ReDO project. Summary results are outlined and an assessment of clinical trial activity also described. The database has been made available as an online open-access resource (http://www.redo-project.org/db/).
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Cancer therapy reduces tumor burden by killing tumor cells, yet it simultaneously creates tumor cell debris that may stimulate inflammation and tumor growth. Thus, conventional cancer therapy is inherently a double-edged sword. In this study, we show that tumor cells killed by chemotherapy or targeted therapy ("tumor cell debris") stimulate primary tumor growth when coinjected with a subthreshold (nontumorigenic) inoculum of tumor cells by triggering macrophage proinflammatory cytokine release after phosphatidylserine exposure. Debris-stimulated tumors were inhibited by antiinflammatory and proresolving lipid autacoids, namely resolvin D1 (RvD1), RvD2, or RvE1. These mediators specifically inhibit debris-stimulated cancer progression by enhancing clearance of debris via macrophage phagocytosis in multiple tumor types. Resolvins counterregulate the release of cytokines/chemokines, including TNFα, IL-6, IL-8, CCL4, and CCL5, by human macrophages stimulated with cell debris. These results demonstrate that enhancing endogenous clearance of tumor cell debris is a new therapeutic target that may complement cytotoxic cancer therapies.
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Antineoplásicos/farmacologia , Ácidos Docosa-Hexaenoicos/farmacologia , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Proliferação de Células , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Mediadores da Inflamação/metabolismo , Macrófagos/metabolismo , Melanoma Experimental , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Fagocitose , Fosfatidilserinas/metabolismo , Carga Tumoral , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Chloroquine (CQ) and hydroxychloroquine (HCQ) are well-known 4-aminoquinoline antimalarial agents. Scientific evidence also supports the use of CQ and HCQ in the treatment of cancer. Overall, preclinical studies support CQ and HCQ use in anti-cancer therapy, especially in combination with conventional anti-cancer treatments since they are able to sensitise tumour cells to a variety of drugs, potentiating the therapeutic activity. Thus far, clinical results are mostly in favour of the repurposing of CQ. However, over 30 clinical studies are still evaluating the activity of both CQ and HCQ in different cancer types and in combination with various standard treatments. Interestingly, CQ and HCQ exert effects both on cancer cells and on the tumour microenvironment. In addition to inhibition of the autophagic flux, which is the most studied anti-cancer effect of CQ and HCQ, these drugs affect the Toll-like receptor 9, p53 and CXCR4-CXCL12 pathway in cancer cells. In the tumour stroma, CQ was shown to affect the tumour vasculature, cancer-associated fibroblasts and the immune system. The evidence reviewed in this paper indicates that both CQ and HCQ deserve further clinical investigations in several cancer types. Special attention about the drug (CQ versus HCQ), the dose and the schedule of administration should be taken in the design of new trials.
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In this study we have tested the efficacy of citrate therapy in various cancer models. We found that citrate administration inhibited A549 lung cancer growth and additional benefit accrued in combination with cisplatin. Interestingly, citrate regressed Ras-driven lung tumors. Further studies indicated that citrate induced tumor cell differentiation. Additionally, citrate treated tumor samples showed significantly higher infiltrating T-cells and increased blood levels of numerous cytokines. Moreover, we found that citrate inhibited IGF-1R phosphorylation. In vitro studies suggested that citrate treatment inhibited AKT phosphorylation, activated PTEN and increased expression of p-eIF2a. We also found that p-eIF2a was decreased when PTEN was depleted. These data suggest that citrate acts on the IGF-1R-AKT-PTEN-eIF2a pathway. Additionally, metabolic profiling suggested that both glycolysis and the tricarboxylic acid cycle were suppressed in a similar manner in vitro in tumor cells and in vivo but only in tumor tissue. We reproduced many of these observations in an inducible Her2/Neu-driven breast cancer model and in syngeneic pancreatic tumor (Pan02) xenografts. Our data suggests that citrate can inhibit tumor growth in diverse tumor types and via multiple mechanisms. Dietary supplementation with citrate may be beneficial as a cancer therapy.