Search

Despite mounting evidence that oncolytic viruses can be effective in treating cancer, understanding the details of the interactions between tumour cells, oncolytic viruses and immune cells that could lead to tumour control or tumour escape is still an open problem. Mathematical modelling of cancer oncolytic therapies has been used to investigate the biological mechanisms behind the observed temporal patterns of tumour growth. However, many models exhibit very complex dynamics, which renders them difficult to investigate. In this case, bifurcation diagrams could enable the visualisation of model dynamics by identifying (in the parameter space) the particular transition points between different behaviours. Here, we describe and investigate two simple mathematical models for oncolytic virus cancer therapy, with constant and immunitydependent carrying capacity. While both models can exhibit complex dynamics, namely fixed points, periodic orbits and chaotic behaviours, only the model with immunity-dependent carrying capacity can exhibit them for biologically realistic situations, i.e., before the tumour grows too large and the experiment is terminated. Moreover, with the help of the bifurcation diagrams we uncover two unexpected behaviours in virus-tumour dynamics: (i) for short virus half-life, the tumour size seems to be too small to be detected, while for long virus half-life the tumour grows to larger sizes that can be detected; (ii) some model parameters have opposite effects on the transient and asymptotic dynamics of the tumour. [ABSTRACT FROM AUTHOR]

We have studied the ability of adenoviral (Ad) vectors expressing the cytokines IL-2 or IL-12 to mediate regression of established tumors in a mouse model of mammary adenocarcinoma. Previous results indicated that intratumoral injection of vectors expressing IL-2 (AdCAIL-2) or IL-12 (AdmIL-12.1) induced complete tumor regression in approximately 30–40% of treated animals. In the current studies, we investigated the mechanism of tumor killing in responding animals and the efficacy of AdIL-2 and AdIL-12 vector administration in combination compared with the use of either vector alone. Animals bearing subcutaneous mammary tumors were injected intratumorally with Ad vectors expressing IL-2 or IL-12 or were coinjected with both vectors. Animals receiving the combination treatment responded substantially better than animals which had received either vector alone, with 65% of animals treated with both vectors undergoing complete tumor regression. In all three treatment regimens, tumor regression was associated with the presence of specific antitumor antigen cytotoxic T-lymphocytes (CTLs), which secreted elevated levels of IFN-γ. Consistent with circulating CTLs being involved in regression, when animals bearing bilateral tumors were inoculated in a single tumor with IL-2 or IL-12 expressing vectors, both tumors regressed in many cases. Again, treatment with both AdCAIL-2 and AdmIL-12.1 was most effective, with 63% of animals undergoing complete regression of both treated and untreated tumors, compared to 18 or 22% of animals injected with either AdCAIL-2 or AdmIL-12.1 alone. These data indicate that the combination of IL-2 and IL-12 is a more effective inducer of antitumor immune responses than either one alone, and that the resulting antitumor responses are effective in mediating the regression of distal untreated tumors, a property which may aid in the treatment of metastatic disease. [ABSTRACT FROM AUTHOR]

Adenovirus (Ad) vectors are being intensively studied as vehicles for cancer gene therapy. We have been exploring the benefits of direct intratumoral injection of Ads expressing cytokines for immunotherapy. Our previous work demonstrated that therapy using a vector expressing interleukin-12 (AdmIL-12.1) produced regressions in approxi- mately 80% of treated tumors, supporting further preclinical investigations. Recent reports have shown that immunity to Ad can be a major limiting factor in Ad-mediated gene transfer. As most animal studies with Ad vectors have involved nonimmune hosts, it remains difficult to predict how effective these treatments will be in humans, where the majority of individuals have had previous exposure to Ad. To address this question, we compared the effectiveness of the AdmIL-12.1 cancer therapy in naive and Ad-immune mice. We found that both groups responded equally well to treatment and that the response to AdmIL-12.1 in both groups resulted in the generation of CTL reactive against tumor antigen, indicating that antitumor immunity was achieved. Peak transgene expression in the tumor was only reduced by 2.4-fold in Ad-immune animals compared with nonimmune mice. It was also observed that in naive animals, the virus disseminated from the site of the tumor following injection and by 72 h substantial transgene expression was detected in peripheral organs, most notably the liver. Transgene expression in the liver of Ad-immune animals was reduced by greater than 1000-fold relative to that in naive mice. These results strongly support the clinical utility of Ad-based cancer gene therapy and suggest that Ad immunity may be advantageous in that it is not a complete block to gene transfer in the tumor and it greatly reduces virus dissemination. [ABSTRACT FROM AUTHOR]

We have previously demonstrated that uptake of the amino acid amide sarcosinamide by the glioma cell line SK-MG-1 occurs via the catecholamine carrier that accommodates epinephrine (Km = 0.284 mM; Vmax = 0.154 nmol/10(6) cells/min). Sarcosinamide chloroethylnitrosourea (SarCNU), a new anticancer agent that exerts increased in vitro antitumor activity against gliomas as compared with BCNU (bis-chloroethylnitrosourea), the standard agent of choice, competitively inhibits sarcosinamide uptake by SK-MG-1 cells [inhibition constant (Ki) = 3.26 mM]. Using radiolabeled N-[3H]-sarcosinamide, we determined the transport of sarcosinamide in HT-29 colon-cancer cells, in Calu-1 lung-cancer cells, and in normal foreskin DHF fibroblasts. Sarcosinamide transport was linear for up to 1 min at 22 degrees C. In HT-29 cells and DHF fibroblasts, the uptake of sarcosinamide followed Michaelis-Menten kinetics of carrier-mediated transport. In HT-29 cells the Michaelis constant (Km) was 2.76 +/- 0.1 mM and the maximal velocity (Vmax) was 2.03 +/- 0.1 nmol/10(6) cells/min, whereas in DHF fibroblasts the respective values were 6.58 +/- 3.90 mM and 12.08 +/- 8.20 nmol/10(6) cells/min. In these two cell lines, neither epinephrine nor leucine significantly reduced sarcosinamide transport. In Calu-1 cells there was no evidence of carrier-mediated transport of either sarcosinamide or epinephrine. These nonglial cell lines lack a high-affinity catecholamine carrier. The increased cytotoxicity of SarCNU in gliomas may correlate with the presence of a high-affinity catecholamine carrier. [ABSTRACT FROM AUTHOR]

Abstract Scientific discoveries that provide strong evidence of antitumor effects in preclinical models often encounter significant delays before being tested in patients with cancer. While some of these delays have a scientific basis, others do not. We need to do better. Innovative strategies need to move into early stage clinical trials as quickly as it is safe, and if successful, these therapies should efficiently obtain regulatory approval and widespread clinical application. In late 2009 and 2010 the Society for Immunotherapy of Cancer (SITC), convened an "Immunotherapy Summit" with representatives from immunotherapy organizations representing Europe, Japan, China and North America to discuss collaborations to improve development and delivery of cancer immunotherapy. One of the concepts raised by SITC and defined as critical by all parties was the need to identify hurdles that impede effective translation of cancer immunotherapy. With consensus on these hurdles, international working groups could be developed to make recommendations vetted by the participating organizations. These recommendations could then be considered by regulatory bodies, governmental and private funding agencies, pharmaceutical companies and academic institutions to facilitate changes necessary to accelerate clinical translation of novel immune-based cancer therapies. The critical hurdles identified by representatives of the collaborating organizations, now organized as the World Immunotherapy Council, are presented and discussed in this report. Some of the identified hurdles impede all investigators; others hinder investigators only in certain regions or institutions or are more relevant to specific types of immunotherapy or first-in-humans studies. Each of these hurdles can significantly delay clinical translation of promising advances in immunotherapy yet if overcome, have the potential to improve outcomes of patients with cancer.

Background: Initiation of antitumor immunity is reliant on the stimulation of dendritic cells (DCs) to present tumor antigens to naïve T cells and generate effector T cells that can kill cancer cells. Induction of immunogenic cell death after certain types of cytotoxic anticancer therapies can stimulate T cell-mediated immunity. However, cytotoxic therapies simultaneously activate multiple types of cellular stress and programmed cell death; hence, it remains unknown what types of cancer cell death confer superior antitumor immunity., Methods: Murine cancer cells were engineered to activate apoptotic or pyroptotic cell death after Dox-induced expression of procell death proteins. Cell-free supernatants were collected to measure secreted danger signals, cytokines, and chemokines. Tumors were formed by transplanting engineered tumor cells to specifically activate apoptosis or pyroptosis in established tumors and the magnitude of immune response measured by flow cytometry. Tumor growth was measured using calipers to estimate end point tumor volumes for Kaplan-Meier survival analysis., Results: We demonstrated that, unlike apoptosis, pyroptosis induces an immunostimulatory secretome signature. In established tumors pyroptosis preferentially activated CD103 + and XCR1 + type I conventional DCs (cDC1) along with a higher magnitude and functionality of tumor-specific CD8 + T cells and reduced number of regulatory T cells within the tumor. Depletion of cDC1 or CD4 + and CD8 + T cells ablated the antitumor response leaving mice susceptible to a tumor rechallenge., Conclusion: Our study highlights that distinct types of cell death yield varying immunotherapeutic effect and selective activation of pyroptosis can be used to potentiate multiple aspects of the anticancer immunity cycle., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Understanding the efficacy of SARS-CoV-2 vaccination in people on immunosuppressive drugs, including those with rheumatoid arthritis (RA), is critical for their protection. Vaccine induced protection requires antibodies, CD4 + T cells, and CD8 + T cells, but it is unclear if these are equally affected by immunomodulatory drugs. Here, we determined how humoral and cellular SARS-CoV-2 vaccination responses differed between people with RA and controls, and which drug classes impacted these responses. Blood was collected from participants with RA on immunomodulatory drugs and controls after their second, third, and fourth SARS-CoV-2 vaccinations. Receptor binding domain (RBD)-specific antibodies were quantified by ELISA. Spike-specific memory T cells were quantitated using flow cytometry. Linear mixed models assessed the impact of age, sex, and immunomodulatory drug classes on SARS-CoV-2 vaccination responses. Compared to non-RA controls (n = 35), participants with RA on immunomodulatory drugs (n = 62) had lower anti-RBD IgG and spike-specific CD4 + T cell levels, but no deficits in spike-specific CD8 + T cells, following SARS-CoV-2 vaccination. Use of costimulation inhibitors was associated with lower humoral responses. JAK inhibitors were associated with fewer spike-specific CD4 + T cells. Participants with RA on immunomodulatory drugs mounted weaker responses to SARS-CoV-2 vaccination, with different drug classes impacting the cellular and humoral compartments., (© 2023. The Author(s).)

Introduction: There are limited data on the longitudinal impact of Lyme disease. Predictors of recovery have not been fully established using validated data collection instruments. There are sparse data on the immunological response to infection over time., Methods and Analysis: This study is a longitudinal cohort study that will recruit 120 participants with Lyme disease in Ontario and Nova Scotia, Canada, with follow-up for up to 24 months. Data will be collected using the Short-Form 36 physical and mental component summaries, Depression and Anxiety Severity Scale Questionnaire, Fatigue Severity Scale and a battery of neuropsychological tests. Mononuclear cells, gene expression and cytokine profiling from blood samples will be used to assess immunological response. Analyses will include the use of non-linear mixed-effects modelling and proportional hazards models., Ethics and Dissemination: Ethics approval has been obtained from ethics boards at McMaster University (Hamilton Integrated Research Ethics Board) (7564), Queens University (EMD 315-20) and Nova Scotia Health Research Ethics Board (1027173), and the study is enrolling participants. Written informed consent is obtained from all participants. The results will be disseminated by publication in a peer-reviewed journal and presented at a relevant conference. A brief report will be provided to decision-makers and patient groups., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: In patients with metastatic lung adenocarcinoma, evidence-based first-line treatment decisions require analysis of tumors for genomic alterations (GAs). Optimizing the genotyping paradigm may improve the delivery of precision oncology care. Actionable GAs can be identified by analyzing tumor tissue or circulating tumor DNA using liquid biopsy. Consensus guidelines for when to use liquid biopsy have not been established. We evaluated the routine use of liquid biopsy performed simultaneously with tissue testing in patients with newly diagnosed, stage IV lung adenocarcinoma., Methods: We performed a retrospective study comparing patients who underwent tissue genotyping alone (standard biopsy group) with patients who had simultaneous liquid and tissue genotyping (combined biopsy group). We examined the time to reach a final diagnosis, the need for repeat biopsies, and diagnostic accuracy., Results: Forty two patients in the combined biopsy group and 78 in the standard biopsy group met the inclusion criteria. The standard group had a mean time to diagnosis of 33.5 days, compared with 20.6 days in the combined group ( P < .001 by two-tailed t -test). In the combined group, 14 patients did not have sufficient tissue for molecular analysis (30%); however, in 11 (79%) of these patients, liquid biopsy identified a GA that eliminated the need for a second tissue biopsy. In patients who completed both tests, each test found actionable GAs missed by the other., Conclusion: Performing liquid biopsy simultaneously with tissue genotyping is feasible in an academic community medical center. Potential advantages of simultaneous liquid and tissue biopsies include shorter time to obtain a definitive molecular diagnosis, reduced need for a repeat biopsy, and improved detection of actionable mutations, although a sequential strategy that saves costs by beginning with a liquid biopsy may be ideal.

Background: For the local management of pulmonary malignancies, surgical resection and stereotactic body radiation therapy (SBRT) are mutually exclusive treatments. This study aims to assess the effectiveness of SBRT on reducing tumor viability at a histologic level in the context of pulmonary metastases., Methods: This protocol describes an open-label unblinded single-arm prospective Phase 2 trial to determine the effects of dual treatment of pulmonary metastasis amenable to curative resection using neoadjuvant SBRT followed by surgical resection, the Post SBRT Pulmonary Metastasectomy (PSPM) trial. Sample size require 39 patients, with an anticipated study duration of 30-36 months. Following completion of SBRT, eligible patients will be assessed at the 4-6-week mark by the treating radiation oncologist and thoracic surgeon with a post-treatment computed tomography (CT) of the chest. Patients with no disease progression will undergo scheduled surgical resection of all metastatic tumors at 8-12 weeks post SBRT. Patients will then be evaluated postoperatively at 30 days, and every 6 months for a total of 36 months with surveillance CT scans. Patients will also undergo sequential serologic evaluation of circulating tumor DNA (ctDNA) levels throughout their respective treatment pathway. The primary outcome of this study is the rate of complete pathologic response (pCR) following SBRT, assess using the International Association for the Study of Lung Cancer (IASLC) multidisciplinary recommendations for pathologic assessment of lung cancer resection specimens after neoadjuvant therapy. Secondary outcomes include overall survival (OS), disease free survival (DFS), local recurrence rates, cancer histology effects on pCR and treatment related complications, and treatment effect on ctDNA levels. Primary and secondary outcomes will be analyzed using Fisher's Exact test and Student's t -test based on data type. Cox-proportional hazard ratios will be used to evaluate OS and DFS, using the log rank test., Discussion: In evaluating the effect of SBRT on pulmonary metastasis at a histologic level, this trial may increase the use of this modality in selected patients who would otherwise only undergo surgery for disease that has already metastasized. Also, the trial provides secondary benefits of evaluating the abscopal effects of radiation on pulmonary metastatic disease, and serves as a platform for more comprehensive large-scale research in this field., Trial Registration: ClinicalTrials.gov identifier: NCT04160143 (HiREB: 7925)., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tcr.amegroups.com/article/view/10.21037/tcr-22-232/coif). The authors have no conflicts of interest to declare., (2022 Translational Cancer Research. All rights reserved.)

Survivors of severe SARS-CoV-2 infections frequently suffer from a range of post-infection sequelae. Whether survivors of mild or asymptomatic infections can expect any long-term health consequences is not yet known. Herein we investigated lasting changes to soluble inflammatory factors and cellular immune phenotype and function in individuals who had recovered from mild SARS-CoV-2 infections ( n = 22), compared to those that had recovered from other mild respiratory infections ( n = 11). Individuals who had experienced mild SARS-CoV-2 infections had elevated levels of C-reactive protein 1-3 months after symptom onset, and changes in phenotype and function of circulating T-cells that were not apparent in individuals 6-9 months post-symptom onset. Markers of monocyte activation, and expression of adherence and chemokine receptors indicative of altered migratory capacity, were also higher at 1-3 months post-infection in individuals who had mild SARS-CoV-2, but these were no longer elevated by 6-9 months post-infection. Perhaps most surprisingly, significantly more T-cells could be activated by polyclonal stimulation in individuals who had recently experienced a mild SARS-CoV-2, infection compared to individuals with other recent respiratory infections. These data are indicative of prolonged immune activation and systemic inflammation that persists for at least three months after mild or asymptomatic SARS-CoV-2 infections.

CD133 marks self-renewing cancer stem cells (CSCs) in a variety of solid tumors, and CD133+ tumor-initiating cells are known markers of chemo- and radio-resistance in multiple aggressive cancers, including glioblastoma (GBM), that may drive intra-tumoral heterogeneity. Here, we report three immunotherapeutic modalities based on a human anti-CD133 antibody fragment that targets a unique epitope present in glycosylated and non-glycosylated CD133 and studied their effects on targeting CD133+ cells in patient-derived models of GBM. We generated an immunoglobulin G (IgG) (RW03-IgG), a dual-antigen T cell engager (DATE), and a CD133-specific chimeric antigen receptor T cell (CAR-T): CART133. All three showed activity against patient-derived CD133+ GBM cells, and CART133 cells demonstrated superior efficacy in patient-derived GBM xenograft models without causing adverse effects on normal CD133+ hematopoietic stem cells in humanized CD34+ mice. Thus, CART133 cells may be a therapeutically tractable strategy to target CD133+ CSCs in human GBM or other treatment-resistant primary cancers., Competing Interests: Declaration of Interests P.V., C.V., R.W., J.M., and S.S. have patents around CD133 binding agents and uses thereof. These patents include Canadian Patent Application no. 2,962,157; Chinese Patent Application no. 2017800782373; European Patent Application no. EP17863201; Japanese Patent Application no. 2019-521046; and U.S. Patent Application no. 16/342,807. P.V., C.V., J.M., and S.S. are also shareholders of Empirica Therapeutics, which has an exclusive license to the IP as mentioned above. P.V. and D.B. are employees of Empirica Therapeutics., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Given the limited ability of hospice patients to assess, monitor, and respond to substandard care, quality oversight has an important role to play in the hospice sector. The IMPACT Act of 2014 required that agencies be recertified at least every three years, but it did not otherwise alter hospice quality oversight. Objectives: To illuminate the current hospice quality oversight process and discuss its role alongside other government monitoring and public reporting efforts. Methods: Retrospective analysis (2006-2015) concerning hospice accreditation status, deficiency trends, survey frequency and deficiency outcomes, and termination from the Medicare program. Results: The proportion of privately accredited hospice agencies increased from 15% to 39%, a trend driven largely by its increased use among for-profit agencies. The combined rate of deficiencies per agency increased 35% over the past decade, with issues around care planning, aide and homemaker services, and clinical assessment featured most prominently. Nearly half (45%) of all surveys resulted in deficiency citations; however, less than one-in-four hospice agencies were surveyed in a given year. Over the past decade, 28 agencies were terminated from the Medicare program; most of these agencies were unaccredited and operated on a for-profit basis. Conclusions: The IMPACT Act addressed one of the biggest shortcomings in hospice oversight. Our findings highlight additional reforms that could be considered. First, reporting inspection results from private and public recertification surveys could promote greater transparency and accountability. Second, making a wider range of intermediate sanctions available to oversight agencies could enhance enforcement efforts and, ideally, incentivize agencies to improve quality of care.

In recent years the use of immunomodulating therapy to treat various cancers has been on the rise. Three checkpoint inhibitors have been approved by the Food and Drug Administration (ipilimumab, pembrolizumab and nivolumab). The use of these drugs comes with serious adverse events related to excessive immune activation, collectively known as immune-related adverse events (irAEs). We conducted a system-based review of 139 case reports/case series that have described these adverse events between January 2016 and April 2018, found in the PubMed database. There was a broad spectrum of presentations, doses and checkpoint inhibitors used. The most common check point inhibitor observed in our literature review was nivolumab. The most common adverse effects encountered were colitis (14/139), hepatitis (11/139), adrenocorticotropic hormone insufficiency (12/139), hypothyroidism (7/139), type 1 diabetes (22/139), acute kidney injury (16/139) and myocarditis (10/139). The treatment most commonly consisted of cessation of the immune checkpoint inhibitor, initiation of steroids and supportive therapy. This approach provided a complete resolution in a majority of cases; however, there were many that developed long-term adverse events with deaths reported in a few cases. The endocrine system was the mostly commonly affected with the development of type 1 diabetes mellitus or diabetic ketoacidosis being the most frequently reported adverse events. While immunomodulating therapy is a significant advance in the management of various malignancies, it is capable of serious adverse effects. Because the majority of the cases developed pancreatic dysfunction within five cycles of therapy, in addition to the evaluation of other systems, pancreatic function should be closely monitored to minimize adverse impact on patients., Competing Interests: The authors declare that there is no conflict of interest regarding the publication of this paper.