Preventable incidence cases from non-communicable diseases attributable to insufficient physical activity in Chile.

OBJECTIVES: Lack of sufficient physical activity (PA) has been associated with an increased risk of several non-communicable diseases (NCDs) and all-cause mortality. This study aimed to estimate the number of preventable incidence cases of NCDs attributable to insufficient PA in the Chilean population. STUDY DESIGN: Comparative risk assessment modelling study. METHODS: This study examined data from 5834 participants aged ≥20 years from the Chilean National Survey (2016-2017). PA was assessed by the Global Physical Activity Questionnaire (GPAQ), and metabolic equivalent of tasks (METs) were assigned according to PA intensity. Estimated incidence cases of NCDs in Chile in 2019 were obtained from the Global Burden of Disease study. Relative risks for breast cancer, colon cancer, ischaemic heart disease, diabetes and stroke were obtained from a published meta-analysis and applied to the prevalence of insufficient PA estimates through the potential impact fraction equation. RESULTS: High levels of PA (≥8000 MET-min/week) could potentially avoid more than 22,000 (64.6 %) incidence NCD cases, ranging from 498 (10.1 %) preventable cases of breast cancer to 5629 (14.7 %) cases of diabetes. Other modelled scenarios also showed to reduce the incidence cases of all five NCDs but to a lesser extent; where at least PA recommendation was achieved, preventable NCDs were reduced by 6522 cases (18.7 %), and where a 10 % relative reduction in insufficient PA level in the population was achieved, preventable NCDs were reduced by 651 (1.8 %) cases. CONCLUSIONS: The study results provide estimates for the incidence cases of preventable NCDs attributable to insufficient PA, highlighting the important role of PA in NCD prevention in Chile.

[Neurological complications in critical patients with COVID-19]. / Complicaciones neurológicas en pacientes críticos por SARS-CoV-2.

Introduction: We analysed the neurological complications of patients with severe SARS-CoV-2 infection who required intensive care unit (ICU) admission. Patients and methods: We conducted a retrospective, observational, descriptive study of consecutive patients admitted to the ICU due to severe respiratory symptoms secondary to SARS-CoV-2 infection between 1 April and 1 June 2020. Results: We included 30 patients with neurological symptoms; 21 were men (72.40%), and mean age (standard deviation [SD]) was 57.41 years (11.61). The mean duration of ICU stay was 18.83 days (14.33). The neurological conditions recorded were acute confusional syndrome in 28 patients (93.33%), neuromuscular disease in 15 (50%), headache in 5 (16.66%), cerebrovascular disease in 4 (13.33%), and encephalopathies/encephalitis in 4 (13.33%). CSF analysis results were normal in 6 patients (20%). Brain MRI or head CT showed alterations in 20 patients (66.6%). EEG was performed in all patients (100%), with 8 (26.66%) showing abnormal findings. In 5 of the 15 patients with clinical myopathy, diagnosis was confirmed with electroneuromyography. We found a correlation between older age and duration of ICU stay (P = .002; 95% CI: 4.032-6.022; OR: 3,594). Conclusions: Severe COVID-19 mainly affects men, as observed in other series. Half of our patients presented acute myopathy, and almost all patients left the ICU with acute confusional syndrome, which fully resolved; no correlation was found with EEG or neuroimaging findings. Older age is associated with longer ICU stay.

Ex vivo conditioning with IL-12 protects tumor-infiltrating CD8+ T cells from negative regulation by local IFN-γ.

Optimal ex vivo expansion protocols for adoptive cell therapy (ACT) must yield T cells able to effectively home to tumors and survive the inhospitable conditions of the tumor microenvironment (TME), while simultaneously exerting persistent anti-tumor effector functions. Our previous work has shown that ex vivo activation in the presence of IL-12 can induce optimal expansion of murine CD8+ T cells, thus resulting in significant tumor regression after ACT mostly via sustained secretion of IFN-γ. In this report, we further elucidate the mechanism of this potency, showing that IL-12 additionally counteracts the negative regulatory effects of autocrine IFN-γ. IL-12 not only downregulates PD-1 expression by T cells, thus minimizing the effects of IFN-γ-induced PD-L1 upregulation by tumor stromal cells, but also inhibits IFNγR2 expression, thereby protecting T cells from IFN-γ-induced cell death. Thus, the enhanced anti-tumor activity of CD8+ T cells expanded ex vivo in the presence of IL-12 is due not only to the ability of IL-12-stimulated cells to secrete sustained levels of IFN-γ, but also to the additional capacity of IL-12 to counter the negative regulatory effects of autocrine IFN-γ.

MEK inhibition abrogates sunitinib resistance in a renal cell carcinoma patient-derived xenograft model.

BACKGROUND: Renal cell carcinoma (RCC) patients treated with tyrosine kinase inhibitors (TKI) typically respond initially, but usually develop resistance to therapy. We utilised transcriptome analysis to identify gene expression changes during development of sunitinib resistance in a RCC patient-derived xenograft (PDX) model. METHODS: RCC tumours were harvested during pre-treatment, response and escape phases. Direct anti-proliferative effects of sunitinib plus MEK inhibitor were assessed. Activation status (phosphorylation) of MEK1/2 and ERK1/2 was determined, myeloid-derived suppressor cells (MDSC) sub-fractions were quantitated and G-CSF was measured by ELISA. RESULTS: During the response phase, tumours exhibited 91% reduction in volume, characterised by decreased expression of cell survival genes. After 4-week treatment, tumours developed resistance to sunitinib, associated with increased expression of pro-angiogenic and cell survival genes. During tumour escape, cellular movement, inflammatory response and immune cell trafficking genes were induced, along with intra-tumoural accumulation of MDSC. In this PDX model, either continuous treatment with sunitinib plus MEK inhibitor PD-0325901, or switching from sunitinib to PD-0325901 was effective. The combination of PD-0325901 with TKI suppressed intra-tumoural phospho-MEK1/2, phospho-ERK1/2 and MDSC. CONCLUSIONS: Continuous treatment with sunitinib alone did not maintain anti-tumour response; addition of MEK inhibitor abrogated resistance, leading to improved anti-tumour efficacy.

Efficiency of Indigenous Filamentous Fungi for Biodegradation of Petroleum Hydrocarbons in Medium and Soil: Laboratory Study from Ecuador.

The competence of two fungal isolates for degrading petroleum hydrocarbons was evaluated. The filamentous fungi were isolated from a crude oil-contaminated soil in northeastern Ecuador, and were 99 %-100 % similar in 18S rDNA sequence to the genus Geomyces. Their efficiencies of degradation were tested in vitro for 30 days, using medium and soil microcosm. Residual hydrocarbons were tracked by gas liquid chromatography with a flame ionization detector. The maximum removal percentages of total petroleum hydrocarbons were 77.3 % and 79.9 % for experiments in the medium and soil microcosm, respectively. The percent germination of cow pea (Vigna unguiculata) seeds was increased from 20 % to 100 % upon bioremediation. Isolates sporulated optimally on minimal salts agar medium at pH 5, 25°C temperature, 1 %-1.5 % substrate (crude oil) and 4-6 g L(-1) N-P-K. These findings suggest that these fungal isolates are potential degraders for bioremediation in crude oil-contaminated areas in Ecuador.

A coreceptor-independent transgenic human TCR mediates anti-tumor and anti-self immunity in mice.

Recent advancements in T cell immunotherapy suggest that T cells engineered with high-affinity TCR can offer better tumor regression. However, whether a high-affinity TCR alone is sufficient to control tumor growth, or the T cell subset bearing the TCR is also important remains unclear. Using the human tyrosinase epitope-reactive, CD8-independent, high-affinity TCR isolated from MHC class I-restricted CD4(+) T cells obtained from tumor-infiltrating lymphocytes (TIL) of a metastatic melanoma patient, we developed a novel TCR transgenic mouse with a C57BL/6 background. This HLA-A2-restricted TCR was positively selected on both CD4(+) and CD8(+) single-positive cells. However, when the TCR transgenic mouse was developed with a HLA-A2 background, the transgenic TCR was primarily expressed by CD3(+)CD4(-)CD8(-) double-negative T cells. TIL 1383I TCR transgenic CD4(+), CD8(+), and CD4(-)CD8(-) T cells were functional and retained the ability to control tumor growth without the need for vaccination or cytokine support in vivo. Furthermore, the HLA-A2(+)/human tyrosinase TCR double-transgenic mice developed spontaneous hair depigmentation and had visual defects that progressed with age. Our data show that the expression of the high-affinity TIL 1383I TCR alone in CD3(+) T cells is sufficient to control the growth of murine and human melanoma, and the presence or absence of CD4 and CD8 coreceptors had little effect on its functional capacity.

Metabolic responses of running shod and barefoot in mid-forefoot runners.

BACKGROUND: The purposes of this study were to compare the oxygen cost, metabolic parameters and temporalspatial variables between barefoot and shod running in trained mid-forefoot runners. METHODS: Experienced runners (N.=21; 30±10.9 years; 16 men) performed two separate 20 minute treadmill running bouts at ~77% of estimated maximal heart rate. Rate of oxygen consumption (VO2), energy cost, fuel use and heart rate (HR) were collected continuously using a portable gas analyzer. Three-dimensional motion capture was used to measure temporalspatial parameters. RESULTS: Participants ran at a mean self-selected speed of 3.1±0.3 m/s for both conditions, at intensities corresponding to mean HR values of 146 bpm (shod) and 144 bpm (barefoot). Steady State VO2 was not different between the shod and barefoot conditions (39.4± 4.7 mL/kg*min vs. 40±5.2 mL/kg*min, respectively). The total energy expended in the shod and barefoot conditions was 974±134 kJ and 979±142 kJ. The average non-protein respiratory exchange ratios, proportions and amount of fat and carbohydrate used were not different between conditions. Cadence was 2.5% higher and center of gravity vertical displacement was 0.5 cm less for the barefoot condition (P<0.05). CONCLUSION: In trained mid-forefoot runners experienced with barefoot running, there are not significant metabolic differences between shod and barefoot running conditions. Barefoot running increases cadence and decreases foot contact time and vertical displacement. Experienced participants were likely able to titrate kinematics to standardize energy output and fuel use for a given running distance and speed irrespective of shoe wear.

Assessment of the diagnostic utility of the electroencephalogram in pediatric emergencies.

INTRODUCTION: We analyze the diagnostic utility of urgent EEG (electroencephalogram) performed in children under 16 years of age in our center. MATERIAL AND METHODS: Descriptive, retrospective, observational study of consecutive patients from 0 to 16 years of age, who underwent an urgent EEG for any reason, from January to December 2022. RESULTS: Of the 388 patients, 70 were children: 37 (52.85%) women, and 33 (47.14%) men. Average age: 6.27 ±â€¯4.809. Of the 70 patients, 6 (8.57%) had previous epilepsy. Reasons for consultation: 17 febrile seizures, 10 first focal seizures, 10 first TCG seizures, 6 paroxysmal episodes, 6 absences, 3 myoclonus of extremities, 3 syncope, 2 SE, 2 visual alterations, 2 low level of consciousness, 2 cyanosis, 2 suspected meningitis or encephalitis, 1 choking, 1 atypical headache, 1 chorea, 1 presyncope, 1 language delay. Of the 70 patients, 47 had a normal EEG (67.14%). Of the 47 patients with a normal EEG, 10 were diagnosed with epilepsy, and 3 of them began receiving antiepileptic treatment upon discharge. None of the patients with suspected syncope or paroxysmal disorder (17 patients, 24.28%) had EEG abnormalities. Of the 17 patients with atypical febrile seizures, 3 had EEG abnormalities. CONCLUSIONS: A third of the EEG records performed in the Emergency Department showed alterations, probably due to the time taken. Almost half of the patients with suspected epilepsy or EE showed EEG abnormalities, which confirmed the diagnosis in these cases and encouraged the clinician to start drug treatment. No case with a high suspicion of epilepsy was dismissed due to the normality of the EEG recording in our series. No patient diagnosed with syncope or paroxysmal disorder had EEG abnormalities. Nearly a quarter of patients with atypical febrile seizures showed EEG abnormalities. We barely register cases of status epilepticus, probably due to the degree of complexity of our center.

Clinical and Immunologic Features of Germline Pathogenic Variant-Positive Patients with Melanoma.

PURPOSE: Malignant melanoma represents the most lethal skin cancer with germline predispositions thought to comprise 10% to 15% of all melanoma cases. No studies to date examine the immunologic features that may differentiate survival differences between germline pathogenic variant (gPV)-positive patients with melanoma from gPV-negative patients with melanoma. EXPERIMENTAL DESIGN: Adult patients with melanoma and clinical characteristics suggesting hereditary predisposition to cancer were prospectively recruited to undergo germline testing and flow cytometric analysis of peripheral immune suppressor cells. RESULTS: In this cohort, gPV-positive patients (n = 72) had a significantly improved melanoma-specific survival (MSS) compared with gPV-negative patients (n = 411; HRadj, 0.32; 95% CI, 0.13-0.82; P = 0.01). These survival improvements among gPV-positive patients were most apparent among cutaneous melanoma subtypes (HRadj, 0.12; 95% CI, 0.016-0.86; P = 0.03) and numerically improved in later-stage (IIB-IV) patients (HRadj, 0.34; 95% CI, 0.10-1.11; P = 0.06). Further, gPV-positive patients had a significantly lower level of total circulating PMN-MDSC compared with gPV-negative patients (P = 0.01), which was most apparent in those diagnosed with later stages (IIB-IV) of melanoma (P = 0.009). Finally, a significant upregulation of inflammatory transcriptome signatures in later-stage gPV-positive patients (n = 21) was observed in comparison with gPV-negative patients (n = 173) in the cutaneous melanoma cohort (SKCM) of The Cancer Genome Atlas (TCGA). CONCLUSIONS: gPV-positive patients with melanoma exhibit improved MSS in addition to reduced peripheral PMN-MDSC and an enhanced inflammatory microenvironment.

Phase II Trial of Intermittent Therapy in Patients with Metastatic Renal Cell Carcinoma Treated with Front-line Ipilimumab and Nivolumab.

INTRODUCTION: The combination of ipilimumab/nivolumab is approved for patients with treatment-naïve, intermediate-, and poor-risk metastatic renal cell carcinoma (mRCC), but duration of therapy and safety/efficacy of reinduction at progression is unknown. A phase II trial of intermittent ipilimumab/nivolumab with reinduction at progression was conducted (NCT03126331). PATIENTS AND METHODS: Patients with treatment-naïve mRCC were treated with induction ipilimumab/nivolumab followed by up to 24 weeks of maintenance nivolumab. Patients who achieved a complete response (CR) or partial response (PR) were eligible for inclusion and entered a treatment-free observation period. Patients were restaged every 12 weeks. Patients with no disease progression (PD) remained off therapy. Upon PD, patients were re-challenged with 2 doses of ipilimumab/nivolumab every 3 weeks. Study objectives were to estimate success rate of observation in patients who achieve a CR/PR, and to assess toxicity in patients undergoing reinduction. The study accrued slower than expected and was closed prior to the anticipated accrual goal of 20 patients. RESULTS: Nine patients were included; 89% male, median age 57, 67% clear-cell histology, and 78% intermediate-risk by IMDC criteria. Response to ipilimumab/nivolumab followed by nivolumab maintenance prior to enrollment was 33% CR and 67% PR. Most (78%) patients have remained off therapy, with a median treatment-free interval (TFI) of 34.3 months (range, 8.7-41.8). Two patients had PD off therapy and received 2 cycles of reinduction ipilimumab and nivolumab. No grade 3 or greater toxicities occurred with reinduction. Both patients developed PD at their first scans after reinduction. CONCLUSION: This prospective study demonstrates that patients with a radiographic response to ipilimumab/nivolumab can have prolonged treatment-free intervals. Further studies of de-escalation strategies are warranted. TRIAL REGISTRATION: NCT03126331 [Date of registration 4/27/2017; https://clinicaltrials.gov/ct2/show/NCT03126331].

Phase II Clinical Trial of Pembrolizumab and Chemotherapy Reveals Distinct Transcriptomic Profiles by Radiologic Response in Metastatic Triple-Negative Breast Cancer.

PURPOSE: A single arm, phase II trial of carboplatin, nab-paclitaxel, and pembrolizumab (CNP) in metastatic triple-negative breast cancer (mTNBC) was designed to evaluate overall response rate (ORR), progression-free survival (PFS), duration of response (DOR), safety/tolerability, overall survival (OS), and identify pathologic and transcriptomic correlates of response to therapy. PATIENTS AND METHODS: Patients with ≤2 prior therapies for metastatic disease were treated with CNP regardless of tumor programmed cell death-ligand 1 status. Core tissue biopsies were obtained prior to treatment initiation. ORR was assessed using a binomial distribution. Survival was analyzed via the Kaplan-Meier method. Bulk RNA sequencing was employed for correlative studies. RESULTS: Thirty patients were enrolled. The ORR was 48.0%: 2 (7%) complete responses (CR), 11 (41%) partial responses (PR), and 8 (30%) stable disease (SD). The median DOR for patients with CR or PR was 6.4 months [95% confidence interval (CI), 4-8.5 months]. For patients with CR, DOR was >24 months. Overall median PFS and OS were 5.8 (95% CI, 4.7-8.5 months) and 13.4 months (8.9-17.3 months), respectively. We identified unique transcriptomic landscapes associated with each RECIST category of radiographic treatment response. In CR and durable PR, IGHG1 expression was enriched. IGHG1high tumors were associated with improved OS (P = 0.045) and were concurrently enriched with B cells and follicular helper T cells, indicating IGHG1 as a promising marker for lymphocytic infiltration and robust response to chemo-immunotherapy. CONCLUSIONS: Pretreatment tissue sampling in mTNBC treated with CNP reveals transcriptomic signatures that may predict radiographic responses to chemo-immunotherapy.

Immunotherapy with IL12 and PD1/CTLA4 inhibition is effective in advanced ovarian cancer and associates with reversal of myeloid cell-induced immunosuppression.

The tumor microenvironment (TME) in ovarian cancer (OC) is characterized by immune suppression, due to an abundance of suppressive immune cells populations. To effectively enhance the activity of immune checkpoint inhibition (ICI), there is a need to identify agents that target these immunosuppressive networks while promoting the recruitment of effector T cells into the TME. To this end, we sought to investigate the effect of the immunomodulatory cytokine IL12 alone or in combination with dual-ICI (anti-PD1 + anti-CTLA4) on anti-tumor activity and survival, using the immunocompetent ID8-VEGF murine OC model. Detailed immunophenotyping of peripheral blood, ascites, and tumors revealed that durable treatment responses were associated with reversal of myeloid cell-induced immune suppression, which resulted in enhanced anti-tumor activity by T cells. Single cell transcriptomic analysis further demonstrated striking differences in the phenotype of myeloid cells from mice treated with IL12 in combination with dual-ICI. We also identified marked differences in treated mice that were in remission compared to those whose tumors progressed, further confirming a pivotal role for the modulation of myeloid cell function to allow for response to immunotherapy. These findings provide the scientific basis for the combination of IL12 and ICI to improve clinical response in OC.

Phase 2 study of neoadjuvant treatment with NOV-002 in combination with doxorubicin and cyclophosphamide followed by docetaxel in patients with HER-2 negative clinical stage II-IIIc breast cancer.

NOV-002 (a formulation of disodium glutathione disulfide) modulates signaling pathways involved in tumor cell proliferation and metastasis and enhances anti-tumor immune responsiveness in tumor models. The addition of NOV-002 to chemotherapy has been shown to increase anti-tumor efficacy in animal models and some early phase oncology trials. We evaluated the clinical effects of NOV-002 in primary breast cancer, whether adding NOV-002 to standard preoperative chemotherapy increased pathologic complete response rates (pCR) at surgery, and determined whether NOV-002 mitigated hematologic toxicities of chemotherapy and whether levels of myeloid derived suppressor cells (MDSC) were predictive of response. Forty-one women with newly diagnosed stages II-IIIc HER-2 negative breast cancer received doxorubicin-cyclophosphamide followed by docetaxel (AC â†’ T) every 3 weeks and concurrent daily NOV-002 injections. The trial was powered to detect a doubling of pCR rate from 16 to 32% with NOV-002 plus AC â†’ T (α = 0.05, ß = 80%). Weekly complete blood counts were obtained as well as circulating MDSC levels on day 1 of each cycle were quantified. Of 39 patients with 40 evaluable tumors, 15 achieved a pCR (38%), meeting the primary endpoint of the trial. Concurrent NOV-002 resulted in pCR rates for AC â†’ T chemotherapy higher than previously reported. Patients with lower levels of circulating MDSCs at baseline and on the last cycle of chemotherapy had significantly higher probability of a pCR (P = 0.02). Further evaluation of NOV-002 in a randomized study is warranted.

Kinetics of rebounding of lymphoid and myeloid cells in mouse peripheral blood, spleen and bone marrow after treatment with cyclophosphamide.

Recently, we showed that post cyclophosphamide (CTX) microenvironment benefits the function of transferred T cells. Analysis of the kinetics of cellular recovery after CTX treatment showed that a single 4 mg/mouse CTX treatment decreased the absolute number of leukocytes in the peripheral blood (PBL) at days 3-15, and in the spleen and bone marrow (BM) at days 3-6. The absolute numbers of CD11c(+)CD11b(-) and CD11c(+)CD11b(+) dendritic cells (DCs), CD11b(+) and Ly6G(+) myeloid cells, T and B cells, CD4(+)CD25(+) T regulatory (T(reg)) cells, and NK1.1(+) cells also decreased. The cell numbers returned to control levels during the recovery phase. The absolute numbers of B cells remained low for 3 weeks. The numbers of DCs increased in PBL and spleen at day 9 but returned to control levels at day 15. These data indicate that CTX alters the cellular microenvironment in kinetics that might be precisely targeted to benefit the host.

Cyclophosphamide induces dynamic alterations in the host microenvironments resulting in a Flt3 ligand-dependent expansion of dendritic cells.

Preconditioning a recipient host with lymphodepletion can markedly augment adoptive T cell therapy. However, the precise mechanisms involved are poorly understood. In a recent study, we observed a significant increase in the circulating levels of dendritic cells (DCs; CD11c(+)CD11b(+)) during the recovery from cyclophosphamide (CTX)-induced lymphodepletion. Herein, we demonstrate that the CTX-induced DC expansion was not altered by adjuvant chemotherapy or tumor burden but was augmented by coadministration of granulocyte-colony stimulating factor. Although the increase in the number of DCs was preceded by a systemic expansion of a population expressing the phenotype of myeloid-derived suppressor cells (Gr-1(+)CD11b(+)), depletion of these Gr-1(+) cells had no effect on the noted expansion. Moreover, when Gr-1(high)CD11b(high) cells were sorted from CTX-treated mice and adoptively transferred into control or CTX-treated recipients, they did not differentiate into DCs. Post-CTX expansion of DCs was associated with proliferation of DCs in bone marrow (BM) during the lymphopenic phase and in the blood and spleen during the recovery phase. Furthermore, adoptive transfer of BM cells from CTX-treated mice produced equal numbers of DCs in the blood of either CTX-treated or untreated recipients. CTX induced a dynamic surge in the expression of growth factors and chemokines in BM, where CCR2 and Flt3 signaling pathways were critical for DC expansion. In sum, our data suggest that CTX induces proliferation of DCs in BM prior to their expansion in the periphery. Targeting DCs at these phases would significantly improve their contribution to the clinical application of lymphodepletion to adoptive immunotherapy.

Implementation of the failure modes and effects analysis in a Hospital Radiopharmacy Unit.

AIM: The aim of this study is the implementation in a Hospital Radiopharmacy Unit of a risk analysis methodology in order to proactively identify possible failure modes and prioritize corrective measures. MATERIALS AND METHODS: By means of the failure modes and effects analysis (FMEA), the possible failure modes of each of the stages of the processes of prescription, preparation, and administration of radiopharmaceuticals for diagnostic and therapy were identified. From the variables of severity, probability and detectability, the risk was quantified using the Risk Priority Number (RPN) for each failure mode, sub-process, and type of radiopharmaceutical. Improvement measures were established and the reduction in the RPN value was calculated. RESULTS: A total of 96 failure modes were identified (58 for diagnostic radiopharmaceuticals and 38 for therapy). Biunivocal identification of the patient with the radiopharmaceutical is the failure mode with the highest RPN (60) and the radiolabeling cell sub-process the one that has the highest risk (RPN 286). As a result of the improvement measures, the overall RPN was reduced by 22% for diagnostic radiopharmaceuticals and 20% for therapy. This reduction would be 46% and 31% respectively if radiopharmacy software and a barcode technology in the administration were implemented. CONCLUSIONS: The application of the FMEA methodology as a risk analysis tool allows to identify the critical points of the processes related to radiopharmaceuticals and prioritize measures to reduce the risk.

Old is new again: emergence of thromboembolic complications in cancer patients on immunotherapy.

Cancer immunotherapy has emerged as one of the most important new treatments for cancer in many years, moving rapidly to front-line therapy for several cancers. Cancer immunotherapy is based on treatment with immune checkpoint inhibitors (ICI), which are monoclonal antibodies directed toward immunoregulatory proteins including PD-1, PD-L1 and CTLA-4. ICI inhibit interactions between these proteins and their ligands, disabling physiologic immune regulatory networks and enhancing anti-tumor immunity. However, since the immune response cannot be directed specifically to the tumor, ICI are associated with immune-related adverse events (irAEs) resulting from immune-mediated attack of normal tissues. We and others have reported a high incidence of thrombosis in patients treated with ICI, which may approach 20%. Given the rapidly increasing use of ICIs, it is clear that ICI-Associated Thrombosis (IAT) is a major emerging clinical problem. However, there is a remarkable knowledge gap concerning mechanisms of IAT. IAT may be a composite irAE resulting from activation of blood and vascular cells, leading to thromboinflammation. Cancer itself is an inflammatory disorder, and inducing further inflammation through ICI administration may stimulate procoagulant activity by multiple cell types. Moreover, some blood and vascular cells express ICI target proteins. Here, we review the results of several studies describing the clinical manifestations of IAT, as well as our recent studies demonstrating that elevated levels of myeloid derived suppressor cells and inflammatory cytokines may serve as biomarkers of IAT. It is hoped that the concepts reviewed here may stimulate further research into this important clinical problem.

A high OXPHOS CD8 T cell subset is predictive of immunotherapy resistance in melanoma patients.

Immune checkpoint inhibitor (ICI) therapy continues to revolutionize melanoma treatment, but only a subset of patients respond. Major efforts are underway to develop minimally invasive predictive assays of ICI response. Using single-cell transcriptomics, we discovered a unique CD8 T cell blood/tumor-shared subpopulation in melanoma patients with high levels of oxidative phosphorylation (OXPHOS), the ectonucleotidases CD38 and CD39, and both exhaustion and cytotoxicity markers. We called this population with high levels of OXPHOS "CD8+ TOXPHOS cells." We validated that higher levels of OXPHOS in tumor- and peripheral blood-derived CD8+ TOXPHOS cells correlated with ICI resistance in melanoma patients. We then developed an ICI therapy response predictive model using a transcriptomic profile of CD8+ TOXPHOS cells. This model is capable of discerning responders from nonresponders using either tumor or peripheral blood CD8 T cells with high accuracy in multiple validation cohorts. In sum, CD8+ TOXPHOS cells represent a critical immune population to assess ICI response with the potential to be a new target to improve outcomes in melanoma patients.

Recovery from cyclophosphamide-induced lymphopenia results in expansion of immature dendritic cells which can mediate enhanced prime-boost vaccination antitumor responses in vivo when stimulated with the TLR3 agonist poly(I:C).

Recent preclinical studies suggest that vaccination following adoptive transfer of CD8(+) T cells into a lymphopenic host can augment the therapeutic antitumor responses of the transferred cells. However, the mechanism by which the lymphopenic microenvironment benefits Ag-specific CD8(+) T cell responses remains elusive. We show herein that induction of lymphodepletion by a single 4 mg cyclophosphamide (CTX) treatment induces a marked expansion of immature dendritic cells (DCs) in the peripheral blood on days 8-16 post-CTX (termed restoration phase). In vitro, these DCs were functional, because they showed normal phagocytosis and effective Ag presentation capability upon activation. In vivo, administration of the TLR3 agonist poly(I:C) at the peak of DC expansion (day 12 postlymphopenia) induced inflammatory cytokine production and increases in the number of activated DCs in lymph nodes. Importantly, boosting with gp100(25-33) melanoma peptide combined with poly(I:C) 12 days after an initial priming with the same regimen significantly increased the expansion and the antitumor efficacy of adoptively transferred pmel-1 CD8(+) T cells. These responses were abrogated after depletion of activated DCs during Ag boosting. In conclusion, our data show that CTX treatment induces, during the restoration phase, expansion of immature DCs, which are functional and can be exploited in vivo to foster more effective antitumor adoptive immunotherapy strategies.