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1.
Brain Behav Immun ; 118: 468-479, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38503395

RESUMO

Chronic lymphocytic leukaemia (CLL) is characterised by the clonal proliferation and accumulation of mature B-cells and is often treated with rituximab, an anti-CD20 monoclonal antibody immunotherapy. Rituximab often fails to induce stringent disease eradication, due in part to failure of antibody-dependent cellular cytotoxicity (ADCC) which relies on natural killer (NK)-cells binding to rituximab-bound CD20 on B-cells. CLL cells are diffusely spread across lymphoid and other bodily tissues, and ADCC resistance in survival niches may be due to several factors including low NK-cell frequency and a suppressive stromal environment that promotes CLL cell survival. It is well established that exercise bouts induce a transient relocation of NK-cells and B-cells into peripheral blood, which could be harnessed to enhance the efficacy of rituximab in CLL by relocating both target and effector cells together with rituximab in blood. In this pilot study, n = 20 patients with treatment-naïve CLL completed a bout of cycling 15 % above anaerobic threshold for âˆ¼ 30-minutes, with blood samples collected pre-, immediately post-, and 1-hour post-exercise. Flow cytometry revealed that exercise evoked a 254 % increase in effector (CD3-CD56+CD16+) NK-cells in blood, and a 67 % increase in CD5+CD19+CD20+ CLL cells in blood (all p < 0.005). NK-cells were isolated from blood samples pre-, and immediately post-exercise and incubated with primary isolated CLL cells with or without the presence of rituximab to determine specific lysis using a calcein-release assay. Rituximab-mediated cell lysis increased by 129 % following exercise (p < 0.001). Direct NK-cell lysis of CLL cells - independent of rituximab - was unchanged following exercise (p = 0.25). We conclude that exercise improved the efficacy of rituximab-mediated ADCC against autologous CLL cells ex vivo and propose that exercise should be explored as a means of enhancing clinical responses in patients receiving anti-CD20 immunotherapy.


Assuntos
Antineoplásicos , Leucemia Linfocítica Crônica de Células B , Humanos , Rituximab/farmacologia , Rituximab/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Projetos Piloto , Anticorpos Monoclonais Murinos/farmacologia , Anticorpos Monoclonais Murinos/uso terapêutico
2.
Front Oncol ; 13: 1244090, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37681023

RESUMO

Therapeutic monoclonal antibodies (mAbs) are standard care for many B-cell haematological cancers. The modes of action for these mAbs include: induction of cancer cell lysis by activating Fcγ-receptors on innate immune cells; opsonising target cells for antibody-dependent cellular cytotoxicity or phagocytosis, and/or triggering the classical complement pathway; the simultaneous binding of cancer cells with T-cells to create an immune synapse and activate perforin-mediated T-cell cytotoxicity against cancer cells; blockade of immune checkpoints to facilitate T-cell cytotoxicity against immunogenic cancer cell clones; and direct delivery of cytotoxic agents via internalisation of mAbs by target cells. While treatment regimens comprising mAb therapy can lead to durable anti-cancer responses, disease relapse is common due to failure of mAb therapy to eradicate minimal residual disease. Factors that limit mAb efficacy include: suboptimal effector cell frequencies, overt immune exhaustion and/or immune anergy, and survival of diffusely spread tumour cells in different stromal niches. In this review, we discuss how immunomodulatory changes arising from exposure to structured bouts of acute exercise might improve mAb treatment efficacy by augmenting (i) antibody-dependent cellular cytotoxicity, (ii) antibody-dependent cellular phagocytosis, (iii) complement-dependent cytotoxicity, (iv) T-cell cytotoxicity, and (v) direct delivery of cytotoxic agents.

3.
Front Oncol ; 12: 788113, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35359426

RESUMO

Undertaking a high volume of physical activity is associated with reduced risk of a broad range of clinically diagnosed cancers. These findings, which imply that physical activity induces physiological changes that avert or suppress neoplastic activity, are supported by preclinical intervention studies in rodents demonstrating that structured regular exercise commonly represses tumour growth. In Part 1 of this review, we summarise epidemiology and preclinical evidence linking physical activity or regular structured exercise with reduced cancer risk or tumour growth. Despite abundant evidence that physical activity commonly exerts anti-cancer effects, the mechanism(s)-of-action responsible for these beneficial outcomes is undefined and remains subject to ongoing speculation. In Part 2, we outline why altered immune regulation from physical activity - specifically to T cells - is likely an integral mechanism. We do this by first explaining how physical activity appears to modulate the cancer immunoediting process. In doing so, we highlight that augmented elimination of immunogenic cancer cells predominantly leads to the containment of cancers in a 'precancerous' or 'covert' equilibrium state, thus reducing the incidence of clinically diagnosed cancers among physically active individuals. In seeking to understand how physical activity might augment T cell function to avert cancer outgrowth, in Part 3 we appraise how physical activity affects the determinants of a successful T cell response against immunogenic cancer cells. Using the cancer immunogram as a basis for this evaluation, we assess the effects of physical activity on: (i) general T cell status in blood, (ii) T cell infiltration to tissues, (iii) presence of immune checkpoints associated with T cell exhaustion and anergy, (iv) presence of inflammatory inhibitors of T cells and (v) presence of metabolic inhibitors of T cells. The extent to which physical activity alters these determinants to reduce the risk of clinically diagnosed cancers - and whether physical activity changes these determinants in an interconnected or unrelated manner - is unresolved. Accordingly, we analyse how physical activity might alter each determinant, and we show how these changes may interconnect to explain how physical activity alters T cell regulation to prevent cancer outgrowth.

4.
Eur J Haematol ; 108(6): 493-502, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35184331

RESUMO

OBJECTIVES: Myeloma is characterised by the presence of monoclonal immunoglobulin (M-protein) and the free light chain (FLC) in blood. We investigated whether these M-proteins and FLC are detectable in myeloma patients' saliva to evaluate its utility for non-invasive screening and monitoring of haematological malignancies. METHODS: A total of 57 patients with monoclonal gammopathy and 26 age-matched healthy participants provided paired serum and saliva samples for immunoglobulin characterisation and quantification. RESULTS: Myeloma patients had IgG or IgA M-protein levels ranging up to five times and FLC levels up to a thousand times normal levels of polyclonal immunoglobulins. Despite these highly elevated levels, only two IgG and no IgA M-proteins or FLC could be detected in paired saliva samples. Most patients had reduced levels of serum polyclonal immunoglobulins, but all had normal levels of salivary IgA. CONCLUSIONS: Immunoglobulin transfer from blood is not determined by levels in the systemic circulation and more likely dictated by periodontal inflammation and the integrity of the oral epithelium. Immunoglobulins secreted by bone marrow plasma cells do not substantially enter saliva, which represents a poor medium for myeloma diagnosis. These findings, along with normal salivary IgA levels despite systemic immunoparesis, support a strong partitioning of oral from systemic humoral immunity.


Assuntos
Mieloma Múltiplo , Proteínas do Mieloma , Humanos , Imunoglobulina A , Imunoglobulina G , Cadeias Leves de Imunoglobulina , Imunoglobulinas , Saliva/metabolismo
5.
Ann Surg Oncol ; 29(3): 1839-1850, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34725764

RESUMO

BACKGROUND: Neoadjuvant therapy reduces fitness, muscle mass, and quality of life (QOL). For patients undergoing chemotherapy and surgery for esophagogastric cancer, maintenance of fitness is paramount. This study investigated the effect of exercise and psychological prehabilitation on anaerobic threshold (AT) at cardiopulmonary exercise testing (CPET). Secondary endpoints included peak oxygen uptake (peak VO2), skeletal muscle mass, QOL, and neoadjuvant therapy completion. METHODS: This parallel-arm randomized controlled trial assigned patients with locally advanced esophagogastric cancer to receive prehabilitation or usual care. The 15-week program comprised twice-weekly supervised exercises, thrice-weekly home exercises, and psychological coaching. CPET was performed at baseline, 2 weeks after neoadjuvant therapy, and 1 week preoperatively. Skeletal muscle cross-sectional area at L3 was analyzed on staging and restaging computed tomography. QOL questionnaires were completed at baseline, mid-neoadjuvant therapy, at restaging laparoscopy, and postoperatively at 2 weeks, 6 weeks and 6 months. RESULTS: Fifty-four participants were randomized (prehabilitation group, n = 26; control group, n = 28). No difference in AT between groups was observed post-neoadjuvant therapy. Prehabilitation resulted in an attenuated peak VO2 decline {-0.4 [95% confidence interval (CI) -0.8 to 0.1] vs. -2.5 [95% CI -2.8 to -2.2] mL/kg/min; p = 0.022}, less muscle loss [-11.6 (95% CI -14.2 to -9.0) vs. -15.6 (95% CI -18.7 to -15.4) cm2/m2; p = 0.049], and improved QOL. More prehabilitation patients completed neoadjuvant therapy at full dose [prehabilitation group, 18 (75%) vs. control group, 13 (46%); p = 0.036]. No adverse events were reported. CONCLUSIONS: This study has demonstrated some retention of cardiopulmonary fitness (peak VO2), muscle, and QOL in prehabilitation subjects. Further large-scale trials will help determine whether these promising findings translate into improved clinical and oncological outcomes. Trial Registration ClinicalTrials.gov NCT02950324.


Assuntos
Neoplasias Esofágicas , Neoplasias Gástricas , Neoplasias Esofágicas/terapia , Teste de Esforço , Terapia por Exercício , Humanos , Músculos , Terapia Neoadjuvante , Projetos Piloto , Cuidados Pré-Operatórios , Exercício Pré-Operatório , Qualidade de Vida , Neoplasias Gástricas/terapia
6.
Nitric Oxide ; 63: 13-20, 2017 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-28024935

RESUMO

Uptake of inorganic nitrate (NO3-) into the salivary circulation is a rate-limiting step for dietary NO3- metabolism in mammals. It has been suggested that salivary NO3- uptake occurs in competition with inorganic iodide (I-). Therefore, this study tested the hypothesis that I- supplementation would interfere with NO3- metabolism and blunt blood pressure reductions after dietary NO3- supplementation. Nine healthy adults (4 male, mean ± SD, age 20 ± 1 yr) reported to the laboratory for initial baseline assessment (control) and following six day supplementation periods with 140 mL·day-1 NO3--rich beetroot juice (8.4 mmol NO3-·day-1) and 198 mg potassium gluconate·day-1 (nitrate), and 140 mL·day-1 NO3--rich beetroot juice and 450 µg potassium iodide·day-1 (nitrate + iodide) in a randomized, cross-over experiment. Salivary [I-] was higher in the nitrate + iodide compared to the control and NIT trials (P < 0.05). Salivary and plasma [NO3-] and [NO2-] were higher in the nitrate and nitrate + iodide trials compared to the control trial (P < 0.05). Plasma [NO3-] was higher (474 ± 127 vs. 438 ± 117 µM) and the salivary-plasma [NO3-] ratio was lower (14 ± 6 vs. 20 ± 6 µM), indicative of a lower salivary NO3- uptake, in the nitrate + iodide trial compared to the nitrate trial (P < 0.05). Plasma and salivary [NO2-] were not different between the nitrate and nitrate + iodide trials (P > 0.05). Systolic blood pressure was lower than control (112 ± 13 mmHg) in the nitrate (106 ± 13 mmHg) and nitrate + iodide (106 ± 11 mmHg) trials (P < 0.05), with no differences between the nitrate and nitrate + iodide trials (P > 0.05). In conclusion, co-ingesting NO3- and I- perturbed salivary NO3- uptake, but the increase in salivary and plasma [NO2-] and the lowering of blood pressure were similar compared to NO3- ingestion alone. Therefore, increased dietary I- intake, which is recommended in several countries worldwide as an initiative to offset hypothyroidism, does not appear to compromise the blood pressure reduction afforded by increased dietary NO3- intake.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Suplementos Nutricionais , Iodetos/metabolismo , Nitratos/metabolismo , Pressão Arterial/efeitos dos fármacos , Beta vulgaris , Feminino , Sucos de Frutas e Vegetais , Humanos , Iodetos/administração & dosagem , Masculino , Nitratos/administração & dosagem , Nitratos/sangue , Nitritos/sangue , Nitritos/metabolismo , Saliva/metabolismo , Adulto Jovem
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