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1.
Cureus ; 13(7): e16764, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34476137

ABSTRACT

BACKGROUND:  The mortality of patients admitted to the intensive care unit (ICU) with COVID-19 remains significantly high. Severe COVID-19 pneumonia is characterised by refractory hypoxemia with significant shunting due to a combination of alveolar damage, vascular vasoconstriction, and occlusion due to microthrombi. Similar pathological features are seen in extra-pulmonary organs. However, the influence of thrombotic markers on the risk of mechanical ventilation (MV) and the development of acute kidney injury (AKI) is not fully defined. METHODS:  This was a cross-sectional evaluation of haemostatic and thrombotic markers of COVID-19 patients admitted to the ICU to determine their predictability for the development of thromboembolism and the need for non-invasive or invasive MV, development of AKI, and mortality. RESULTS:  An extended coagulation profile was obtained in 71 SARS-CoV-2 positive patients admitted to the ICU. All patients had acute severe hypoxic respiratory failure and required non-invasive or invasive MV. There were increases in peak D-dimer (3.0 mg/L), factor VIII levels (255 IU/dL) vWF antigen (471 IU/dL) with low ADAMTS13 activity (54.7 IU/dL) compared to the reference ranges. Peak D-dimer was consistently raised in patients who developed AKI and required invasive MV. ADAMTS13/vWF/platelet axis was associated with disease severity, multi-organ dysfunction, and mortality. CONCLUSIONS:  Haematological abnormalities are a common feature of severe COVID-19 pneumonia. We found peak D-dimer and vWF-ADAMTS13-platelet axis are associated with increased ICU severity and outcome in severe COVID-19 patients admitted to ICU. Larger studies are needed to evaluate this more comprehensively.

2.
Ther Adv Vaccines Immunother ; 9: 25151355211017119, 2021.
Article in English | MEDLINE | ID: mdl-34159293

ABSTRACT

Background: Tumor-infiltrating lymphocytes (TILs) and chimeric antigen receptor (CAR) T-cell therapies have demonstrated promising, though limited, efficacy against melanoma. Methods: We designed a model system to explore the efficacy of dual specific T cells derived from melanoma patient TILs by transduction with a Her2-specific CAR. Results: Metastatic melanoma cells in our biobank constitutively expressed Her2 antigen. CAR-TIL produced greater amounts of IFN compared with parental TIL, when co-cultured with Her2 expressing tumor lines, including autologous melanoma tumor lines, although no consistent increase in cytotoxicity by TIL was afforded by expression of a CAR. Results of an in vivo study in NSG mice demonstrated tumor shrinkage when CAR-TILs were used in an adoptive cell therapy protocol. Conclusion: Potential limitations of transduced TIL in our study included limited proliferative potential and a terminally differentiated phenotype, which would need addressing in further work before consideration of clinical translation.

3.
Curr Urol Rep ; 20(7): 39, 2019 May 31.
Article in English | MEDLINE | ID: mdl-31152253

ABSTRACT

PURPOSE OF REVIEW: Rezum is a new minimally invasive treatment for benign prostate enlargement using thermal transurethral water vapour therapy. We review the evidence with advantages and disadvantages of this technique. RECENT FINDINGS: There are five studies reported including a randomised control trial looking at the outcomes of Rezum. The outcomes show an IPSS reduction by 45-60%, QoL improvement with a score reduction of 37-59%, the Qmax improvement by 44-72% and the PVR reduction by 20-38%. Convective water vapour therapy using the Rezum system has been shown to have successful outcomes in the treatment of LUTS resulting from BPH. The reported complications are infrequent and often minor, and it seems to be relatively cost-effective.


Subject(s)
Prostatic Hyperplasia/therapy , Steam , Transurethral Resection of Prostate/methods , Humans , Male , Prostatic Hyperplasia/complications , Treatment Outcome
4.
Ther Adv Urol ; 10(11): 327-333, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30344644

ABSTRACT

Rezum is a minimally invasive transurethral water vapour therapy for benign prostatic enlargement which uses thermal energy for treatment. The short-term results show it to have good outcomes with a potential for outpatient-based treatment preserving sexual function. This review serves to provide an overview of the technique and evaluate its safety and efficacy.

5.
JMIR Mhealth Uhealth ; 5(12): e184, 2017 Dec 06.
Article in English | MEDLINE | ID: mdl-29212628

ABSTRACT

BACKGROUND: Optimal dosing of oral tyrosine kinase inhibitor therapy is critical to treatment success and survival of patients with chronic myeloid leukemia (CML). Drug intolerance secondary to toxicities and nonadherence are significant factors in treatment failure. OBJECTIVE: The objective of this study was to develop and pilot-test the clinical feasibility and acceptability of a mobile health system (REMIND) to increase oral drug adherence and patient symptom self-management among people with CML (chronic phase). METHODS: A multifaceted intervention was iteratively developed using the intervention development framework by Schofield and Chambers, consisting of defining the patient problem and iteratively refining the intervention. The clinical feasibility and acceptability were examined via patient and intervention nurse interviews, which were audiotaped, transcribed, and deductively content analyzed. RESULTS: The intervention comprised 2 synergistically operating elements: (1) daily medication reminders and routine assessment of side effects with evidence-based self-care advice delivered in real time and (2) question prompt list (QPL) questions and routinely collected individual patient adherence and side effect profile data used to shape nurses' consultations, which employed motivational interviewing to support adoption of self-management behaviors. A total of 4 consultations and daily alerts and advice were delivered over 10 weeks. In total, 58% (10/17) of patients and 2 nurses participated in the pilot study. Patients reported several benefits of the intervention: help in establishing medication routines, resolution of symptom uncertainty, increased awareness of self-care, and informed decision making. Nurses also endorsed the intervention: it assisted in establishing pill-taking routines and patients developing effective solutions to adherence challenges. CONCLUSIONS: The REMIND system with nurse support was usable and acceptable to both patients and nurses. It has the potential to improve adherence and side-effect management and should be further evaluated.

6.
Oncotarget ; 8(70): 115215-115229, 2017 Dec 29.
Article in English | MEDLINE | ID: mdl-29383154

ABSTRACT

While immunotherapy employing chimeric antigen receptor (CAR) T cells can be effective against a variety of tumor types, little is known about what happens within the tumor at an ultrastructural level during tumor regression. Here, we used transmission electron microscopy to investigate morphologic and cellular features of tumors responding to immunotherapy composed of adoptive transfer of dual-specific CAR T cells and a vaccine, supported by preconditioning irradiation and interleukin-2. Tumors responded rapidly, and large areas of cell death were apparent by 4 days after treatment. The pleomorphic and metabolically active nature of tumor cells and phagocytic activity of macrophages were apparent in electron microscopic images of tumors prior to treatment. Following treatment, morphologic features of various types of tumor cell death were observed, including apoptosis, paraptosis and necrosis. Large numbers of lipid droplets were evident in tumor cells undergoing apoptosis. Macrophages were the predominant leukocyte type infiltrating tumors before treatment. Macrophages decreased in frequency and number after treatment, whereas an increasing accumulation of neutrophils and T lymphocytes was observed following treatment. Phagocytic activity of macrophages and neutrophils was apparent, while T cells could be observed in close association with tumor cells with potential immunological synapses present. These observations highlight the cellular composition and ultrastructural appearance of tumors undergoing regression mediated by immunotherapy.

7.
Clin Cancer Res ; 23(10): 2478-2490, 2017 May 15.
Article in English | MEDLINE | ID: mdl-27965307

ABSTRACT

Purpose: While adoptive transfer of T cells bearing a chimeric antigen receptor (CAR) can eliminate substantial burdens of some leukemias, the ultimate challenge remains the eradication of large solid tumors for most cancers. We aimed to develop an immunotherapy approach effective against large tumors in an immunocompetent, self-antigen preclinical mouse model.Experimental Design: In this study, we generated dual-specific T cells expressing both a CAR specific for Her2 and a TCR specific for the melanocyte protein (gp100). We used a regimen of adoptive cell transfer incorporating vaccination (ACTIV), with recombinant vaccinia virus expressing gp100, to treat a range of tumors including orthotopic breast tumors and large liver tumors.Results: ACTIV therapy induced durable complete remission of a variety of Her2+ tumors, some in excess of 150 mm2, in immunocompetent mice expressing Her2 in normal tissues, including the breast and brain. Vaccinia virus induced extensive proliferation of T cells, leading to massive infiltration of T cells into tumors. Durable tumor responses required the chemokine receptor CXCR3 and exogenous IL2, but were independent of IFNγ. Mice were resistant to tumor rechallenge, indicating immune memory involving epitope spreading. Evidence of limited neurologic toxicity was observed, associated with infiltration of cerebellum by T cells, but was only transient.Conclusions: This study supports a view that it is possible to design a highly effective combination immunotherapy for solid cancers, with acceptable transient toxicity, even when the target antigen is also expressed in vital tissues. Clin Cancer Res; 23(10); 2478-90. ©2016 AACR.


Subject(s)
Brain Neoplasms/therapy , Breast Neoplasms/therapy , Immunotherapy, Adoptive , Receptor, ErbB-2/immunology , gp100 Melanoma Antigen/immunology , Animals , Autoantigens/administration & dosage , Autoantigens/immunology , Brain Neoplasms/immunology , Brain Neoplasms/pathology , Breast Neoplasms/immunology , CD8-Positive T-Lymphocytes/immunology , Cancer Vaccines/administration & dosage , Cancer Vaccines/immunology , Cell Line, Tumor , Cell Proliferation/drug effects , Female , Flow Cytometry , Humans , Interferon-gamma/antagonists & inhibitors , Interferon-gamma/immunology , Mice , Mice, Transgenic , Receptor, ErbB-2/genetics , Receptors, Antigen, T-Cell/administration & dosage , Receptors, Antigen, T-Cell/immunology , Remission Induction , Vaccinia virus/genetics , Vaccinia virus/immunology , gp100 Melanoma Antigen/genetics
8.
PLoS One ; 10(10): e0140543, 2015.
Article in English | MEDLINE | ID: mdl-26505904

ABSTRACT

Genetically modified CD8+ T lymphocytes have shown significant anti-tumor effects in the adoptive immunotherapy of cancer, with recent studies highlighting a potential role for a combination of other immune subsets to enhance these results. However, limitations in present genetic modification techniques impose difficulties in our ability to fully explore the potential of various T cell subsets and assess the potential of other leukocytes armed with chimeric antigen receptors (CARs). To address this issue, we generated a transgenic mouse model using a pan-hematopoietic promoter (vav) to drive the expression of a CAR specific for a tumor antigen. Here we present a characterization of the immune cell compartment in two unique vav-CAR transgenic mice models, Founder 9 (F9) and Founder 38 (F38). We demonstrate the vav promoter is indeed capable of driving the expression of a CAR in cells from both myeloid and lymphoid lineage, however the highest level of expression was observed in T lymphocytes from F38 mice. Lymphoid organs in vav-CAR mice were smaller and had reduced cell numbers compared to the wild type (WT) controls. Furthermore, the immune composition of F9 mice differed greatly with a significant reduction in lymphocytes found in the thymus, lymph node and spleen of these mice. To gain insight into the altered immune phenotype of F9 mice, we determined the chromosomal integration site of the transgene in both mouse strains using whole genome sequencing (WGS). We demonstrated that compared to the 7 copies found in F38 mice, F9 mice harbored almost 270 copies. These novel vav-CAR models provide a ready source of CAR expressing myeloid and lymphoid cells and will aid in facilitating future experiments to delineate the role for other leukocytes for adoptive immunotherapy against cancer.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , Immunotherapy, Adoptive , Neoplasms/therapy , Recoverin/genetics , Animals , Cell Lineage/immunology , Humans , Mice , Mice, Transgenic , Neoplasms/immunology , Recoverin/biosynthesis , Recoverin/immunology , Signal Transduction , Thymocytes/immunology , Thymus Gland/immunology
9.
Oncoimmunology ; 4(7): e975572, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26140251

ABSTRACT

Advanced stages of cancer often involve multiple tumors in different locations in the body. These tumors are associated with a microenvironment that can influence tumor responses to immunotherapy. Whether tumors and their disparate microenvironment can interact together at distance in a multiple tumor setting, through a form of cross-talk, and affect their responses to immunotherapy has never been described. Our study investigated the cross-talk between two tumors with disparate microenvironments in a mouse model. We demonstrated that immunosuppressive visceral tumors could influence distant subcutaneous (SC) tumors to render them resistant to immunotherapy. We observed distinct modifications in the SC tumor microenvironment following cross-talk with kidney tumors that exhibit a type-2 macrophage-related immunosuppressive microenvironment. Indeed, when a concomitant kidney tumor was present in the mouse, the SC tumors were highly infiltrated with M2 macrophages and had a reduced T cell and NK cell effector immune profile. Finally, blocking the M2-associated chemokine CCL2 or depleting macrophages, significantly improved the effect of immunotherapy on growth of SC tumors in the presence of concomitant kidney tumors. This work emphasizes the potential negative influence that a tumor, with a strong immunosuppressive microenvironment, can exert on distant tumors that would normally be treatment-responsive. This report may lead to a new vision of the prioritization in the treatment of advanced metastatic cancer.

11.
J Cancer Surviv ; 9(3): 462-70, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25573722

ABSTRACT

PURPOSE: This study investigated psychological morbidity, quality of life (QoL), colorectal cancer (CRC)-specific symptoms and supportive care needs in a CRC population at the end of treatment (EOT). METHODS: CRC survivors (n = 152) completed a post-treatment baseline questionnaire as part of a multisite supportive care randomised controlled trial (SurvivorCare). CRC survivors had completed treatment with curative intent within 0 to 6 months. Measures are as follows: Brief Symptom Inventory 18 (BSI-18) (psychological morbidity), EORTC QLQ-C30 and QLQ-CR29 (QoL and CRC-specific symptoms and problems) and Cancer Survivors' Unmet Needs (CaSUN) measure with a simplified response format (unmet needs). Linear regression models were used to compare participants' QoL with a general population sample. Correlation analysis examined associations between psychological morbidity, QoL and CRC-specific symptoms and problems. RESULTS: Average participant age was 64 years, and 51% were male. The majority (68%) had stage 3 disease. In comparison to population norms, CRC survivors had lower depression and anxiety scores (47.4 and 45.6, respectively) but higher somatisation, and lower role, cognitive and social functioning (p < 0.001). CRC survivors had higher fatigue, nausea/vomiting, appetite loss, diarrhoea and financial problems (all p < 0.001), as well as pain (p = 0.002) and constipation (p = 0.019). CRC-specific psychological scores were positively correlated with all three BSI domain scores, and pain and fatigue symptom scores on the QLQ-C30 while negatively correlated with all five functional scales of the QLQ-C30. CONCLUSIONS: CRC survivors reported good mental health at EOT. Role and social functioning were impaired compared to population norms, possibly related to physical symptoms. IMPLICATIONS FOR CANCER SURVIVORS: Findings may help guide consultations with patients and inform the design of more tailored supportive care interventions. TRIAL REGISTRATION: ACTRN12610000207011.


Subject(s)
Survivors/psychology , Aged , Colorectal Neoplasms/psychology , Female , Humans , Male , Middle Aged , Quality of Life , Stress, Psychological , Surveys and Questionnaires
12.
Clin Transl Immunology ; 3(5): e16, 2014 May.
Article in English | MEDLINE | ID: mdl-25505964

ABSTRACT

Immunotherapies are emerging as highly promising approaches for the treatment of cancer. In these approaches, a variety of materials are used to boost immunity against malignant cells. A key component of many of these approaches is functional tumor-specific T cells, but the existence and activity of sufficient T cells in the immune repertoire is not always the case. Recent methods of generating tumor-specific T cells include the genetic modification of patient lymphocytes with receptors to endow them with tumor specificity. These T cells are then expanded in vitro followed by infusion of the patient in adoptive cell transfer protocols. Genes used to modify T cells include those encoding T-cell receptors and chimeric antigen receptors. In this review, we provide an introduction to the field of genetic engineering of T cells followed by details of their use against cancer in the clinic.

13.
PLoS One ; 9(9): e108670, 2014.
Article in English | MEDLINE | ID: mdl-25264896

ABSTRACT

The transcription factor Foxp3 represents the most specific functional marker of CD4+ regulatory T cells (TRegs). However, previous reports have described Foxp3 expression in other cell types including some subsets of macrophages, although there are conflicting reports and Foxp3 expression in cells other than Treg is not well characterized. We performed detailed investigations into Foxp3 expression in macrophages in the normal tissue and tumor settings. We detected Foxp3 protein in macrophages infiltrating mouse renal cancer tumors injected subcutaneously or in the kidney. Expression was demonstrated using flow cytometry and Western blot with two individual monoclonal antibodies. Further analyses confirmed Foxp3 expression in macrophages by RT PCR, and studies using ribonucleic acid-sequencing (RNAseq) demonstrated a previously unknown Foxp3 messenger (m)RNA transcript in tumor-associated macrophages. In addition, depletion of Foxp3+ cells using diphtheria toxin in Foxp3DTR mice reduced the frequency of type-2 macrophages (M2) in kidney tumors. Collectively, these results indicate that tumor-associated macrophages could express Foxp3.


Subject(s)
Forkhead Transcription Factors/biosynthesis , Kidney Neoplasms/immunology , Macrophages/immunology , T-Lymphocytes, Regulatory/immunology , Animals , Antibodies, Monoclonal/immunology , Cell Line, Tumor , Forkhead Transcription Factors/genetics , Mice , Mice, Inbred BALB C , Mice, SCID , RNA, Messenger/biosynthesis
14.
Leuk Res ; 38(8): 948-54, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24934848

ABSTRACT

In order to stimulate antigen presentation and T cell activity against cancer, we treated three different tumor models in mice with the monoclonal antibodies anti-CD40 plus anti-CD137 (BiMab). In a subcutaneous transplantable MC38 colon cancer model, there was significant enhancement in the survival of mice following BiMab treatment. Anti-CD40 has shown considerable success against lymphoma in previous studies by other investigators, and we also showed in this study that, in a model of Eµ-Myc lymphoma, there was a statistically significant enhancement of survival of mice following BiMab treatment. Following the success of the BiMab treatment in the previous two models, we wished to determine if it would be successful in a mouse model of multiple myeloma. Firstly, we tested a transplantable model of disease in which multiple myeloma cells derived from Vk*MYC mice were injected intravenously. A minor proportion of anti-CD137 and BiMab treated mice experienced prolongation of life beyond 250 days. Then we tested the therapy in a spontaneously occurring multiple myeloma model, in Vk*MYC transgenic mice. The majority of mice treated survived longer than control mice, although statistical significance was not demonstrated.


Subject(s)
Antibodies/therapeutic use , CD40 Antigens/antagonists & inhibitors , Lymphoma/therapy , Multiple Myeloma/therapy , Tumor Necrosis Factor Receptor Superfamily, Member 9/antagonists & inhibitors , Animals , CD40 Antigens/immunology , Cell Transformation, Neoplastic/genetics , Disease Models, Animal , Female , Genes, myc , Immunotherapy/methods , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Tumor Cells, Cultured , Tumor Necrosis Factor Receptor Superfamily, Member 9/immunology
15.
PLoS One ; 9(5): e95847, 2014.
Article in English | MEDLINE | ID: mdl-24788789

ABSTRACT

We have found previously that the tumor cell lines, Renca (a renal cancer) and MC38 (a colon tumor) which had been injected subcutaneously in mice, could be successfully treated with a combination therapy of an oligodeoxynucleotide (CpG1826) (injected intratumorally) and anti-CD137 antibody (injected intraperitoneally). Thus the combination treatment was expected to initiate a "danger" signal via TLR9 on immune cells, and the anti-CD137 was expected to further activate T cells. In the present study, we found that several other tumor types injected subcutaneously could also be successfully treated with this combination therapy. In addition, we wished to determine if the treatment could work as effectively in an orthotopic metastatic model, which is more physiologically relevant to cancer in humans. Renca was selected as we were familiar with injecting this orthotopically into the outer cortex of the kidney in mice, and it spontaneously metastasizes to lung and abdominal sites. We tested various routes of delivery of CpG combined with intraperitoneal delivery of anti-CD137. Orthotopic tumors were injected with CpG intratumorally, using ultrasound-guided delivery on multiple occasions, combined with anti-CD137 intraperitoneally. A reduction in primary tumor size was observed following intratumoral injection of CpG compared to other treatments. We found that there was a statistically significant increase in survival of mice with orthotopic Renca tumor following intratumoral injection of CpG. However, we determined that the most effective route of delivery of CpG was intravenous, which led to further significantly enhanced survival of mice when combined with anti-CD137 intraperitoneally, likely due to inhibition of metastatic disease. Our data supports future development of this combination therapy for cancer.


Subject(s)
Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/pharmacology , Kidney Neoplasms/therapy , Oligodeoxyribonucleotides/administration & dosage , Oligodeoxyribonucleotides/pharmacology , Tumor Necrosis Factor Receptor Superfamily, Member 9/immunology , Animals , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/therapeutic use , Cell Line, Tumor , Drug Administration Routes , Drug Interactions , Female , Humans , Kidney Neoplasms/pathology , Mice , Oligodeoxyribonucleotides/therapeutic use , Survival Analysis , Tumor Burden/drug effects
16.
Mol Ther ; 22(1): 18-27, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24048441

ABSTRACT

The tumor microenvironment can promote tumor growth and reduce treatment efficacy. Tumors can occur in many sites in the body, but how surrounding normal tissues at different anatomical sites affect tumor microenvironments and their subsequent response to therapy is not known.We demonstrated that tumors from renal, colon, or prostate cell lines in orthotopic locations responded to immunotherapy consisting of three agonist antibodies, termed Tri-mAb, to a much lesser extent than the same tumor type located subcutaneously. A tissue-specific response to Tri-mAb was confirmed by ex vivo separation of subcutaneous (SC) or orthotopic tumor cells from stromal cells, followed by reinjection of tumor cells into the opposite site. Compared with SC tumors, orthotopic tumors had a microenvironment associated with a type 2 immune response, related to immunosuppression, and an involvement of alternatively activated macrophages in the kidney model. Orthotopic kidney tumors were more highly vascularized than SC tumors. Neutralizing the macrophage- and Th2-associated molecules chemokine (C-C motif) ligand 2 or interleukin-13 led to a significantly improved therapeutic effect. This study highlights the importance of the tissue of implantation in sculpting the tumor microenvironment. These are important fundamental issues in tumor biology and crucial factors to consider in the design of experimental models and treatment strategies.


Subject(s)
Immunotherapy , Neoplasms/immunology , Neoplasms/pathology , Tumor Microenvironment/immunology , Animals , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/pharmacology , CD40 Antigens/antagonists & inhibitors , CD40 Antigens/immunology , Cell Line, Tumor , Chemokine CCL2/immunology , Colonic Neoplasms/immunology , Disease Models, Animal , Gene Expression , Interleukin-13/immunology , Kidney Neoplasms/immunology , Kidney Neoplasms/metabolism , Kidney Neoplasms/pathology , Macrophages/immunology , Macrophages/metabolism , Male , Mice , Neoplasms/mortality , Neoplasms/therapy , Neovascularization, Pathologic/immunology , Organ Specificity/immunology , Prostate/immunology , Receptors, TNF-Related Apoptosis-Inducing Ligand/antagonists & inhibitors , Receptors, TNF-Related Apoptosis-Inducing Ligand/immunology , Treatment Outcome , Tumor Necrosis Factor Receptor Superfamily, Member 9/antagonists & inhibitors , Tumor Necrosis Factor Receptor Superfamily, Member 9/immunology
17.
Oncoimmunology ; 3(7): e946361, 2014.
Article in English | MEDLINE | ID: mdl-25610731

ABSTRACT

This commentary provides the authors' perspective on the article "Routes of delivery for CpG and anti-CD137 for the treatment of orthotopic kidney tumors in mice", published in PLoS ONE. It also discusses the caveats of using subcutaneous tumors to model the treatment of human cancers versus orthotopic mouse models that more closely mimic human disease.

18.
Oncoimmunology ; 3(11): e963395, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25941590

ABSTRACT

In many cancers, regulatory T cells (Treg) play a crucial role in suppressing the effector immune response thereby permitting tumor development. Indeed, in mouse models, their depletion can promote the regression of tumors of various origins, including renal cell carcinoma when located subcutaneous (SC). In the present study, we aimed to assess the importance of Treg immunosuppression in the physiologic context of metastatic renal carcinoma (Renca) disease. To that purpose we inoculated renal tumors orthotopically, intra-kidney (IK), in mice. Treg depletions were performed using anti-CD4 antibody in wild type mice or diphtheria toxin (DT) in Foxp3DTR transgenic mice. Our main observation was that Treg were not the key immunosuppressive component of the IK tumoral microenvironment, compared to the same tumors located SC. We demonstrated that the CD8+ effector immune response was still suppressed in IK tumors when compared to SC tumors, following Treg depletion. Furthermore, the level of program cell death protein (PD)-1 was increased on the surface of CD4+ T cells infiltrating IK tumors compared to SC tumors. Finally, the Treg-independent immunosuppression, occurring in IK tumors, was potent enough to inhibit regression of concomitant SC tumors, normally responsive to Treg depletion. Our findings provide further insight into the immunosuppressive nature of the immune response generated in the kidney microenvironment, suggesting that it can have additional mechanisms in addition to Treg. These observations might help to identify better targets from the kidney tumor microenvironment for future cancer therapies.

19.
Oncoimmunology ; 2(9): e25962, 2013 Sep 01.
Article in English | MEDLINE | ID: mdl-24327938

ABSTRACT

The tumor microenvironment is a complex assortment of cells that includes a variety of leukocytes. The overall effect of the microenvironment is to support the growth of tumors and suppress immune responses. Immunotherapy is a highly promising form of cancer treatment, but its efficacy can be severely compromised by an immunosuppressive tumor microenvironment. Chemotherapy and radiation treatment can mediate tumor reduction through cytotoxic effects, but it is becoming increasingly clear that these forms of treatment can be used to modify the tumor microenvironment to liberate tumor antigens and decrease immunosuppression. Chemotherapy and radiotherapy can be used to modulate the tumor microenvironment to enhance immunotherapy.

20.
Oncoimmunology ; 2(8): e25961, 2013 Aug 01.
Article in English | MEDLINE | ID: mdl-24083084

ABSTRACT

There is much promise in the use of immunotherapy for the treatment of cancer. Approaches such as those using antibodies or adoptive cell transfer can mediate complete tumor regression in a proportion of patients. However, the tumor microenvironment can inhibit immune responses leading to ineffective or suboptimal responses of tumors to immunotherapy in the majority of cases. As our knowledge of the tumor microenvironment increases, many strategies are emerging for changing the immunosuppressive nature of the tumor toward a microenvironment able to support immunity. These strategies aim to enhance the ability of immunotherapies to initiate effective immune responses able to destroy tumors. In this article, we review approaches that use immunomodulators specifically to modify the tumor microenvironment, and their use in combination with other immune-based strategies for cancer therapy.

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