Interactions between immune cell types facilitate the evolution of immune traits.

An essential prerequisite for evolution by natural selection is variation among individuals in traits that affect fitness1. The ability of a system to produce selectable variation, known as evolvability2, thus markedly affects the rate of evolution. Although the immune system is among the fastest-evolving components in mammals3, the sources of variation in immune traits remain largely unknown4,5. Here we show that an important determinant of the immune system's evolvability is its organization into interacting modules represented by different immune cell types. By profiling immune cell variation in bone marrow of 54 genetically diverse mouse strains from the Collaborative Cross6, we found that variation in immune cell frequencies is polygenic and that many associated genes are involved in homeostatic balance through cell-intrinsic functions of proliferation, migration and cell death. However, we also found genes associated with the frequency of a particular cell type that are expressed in a different cell type, exerting their effect in what we term cyto-trans. The vertebrate evolutionary record shows that genes associated in cyto-trans have faced weaker negative selection, thus increasing the robustness and hence evolvability2,7,8 of the immune system. This phenomenon is similarly observable in human blood. Our findings suggest that interactions between different components of the immune system provide a phenotypic space in which mutations can produce variation with little detriment, underscoring the role of modularity in the evolution of complex systems9.

Gilteritinib with or without venetoclax for relapsed/refractory FLT3-mutated acute myeloid leukaemia.

Patients with FLT3-mutated acute myeloid leukaemia (AML) that relapse or are refractory (R/R) to intensive induction have poor outcomes. Gilteritinib has recently become standard-of-care for patients with R/R FLT3-mutated AML. We investigated whether adding venetoclax to gilteritinib (gilt-ven) improves outcomes as compared with gilteritinib monotherapy. We included patients treated with gilteritinib (n = 19) and gilt-ven (n = 17) for R/R AML after intensive chemotherapy. Gilteritinib and gilt-ven groups did not differ in terms of mCRc rates (53% and 65%, p = 0.51) and realization of allogeneic haematopoietic stem-cell transplantation (HSCT, 47% and 35%, p = 0.5). Overall survival (OS) was comparable between groups, although a trend towards better OS was seen with gilt-ven (12-month OS 58.8% [95% CI 39.5%-87.6%]) versus gilteritinib (42.1% [95% CI 24.9%-71.3%] for gilteritinib). Early salvage with gilt-ven versus any other gilteritinib-based approach was associated with the best outcome (p = 0.031). Combination therapy was associated with increased haematological toxicity. In summary, gilt-ven did not improve remissions or HSCT-realization rates in patients with R/R FLT3-mutated AML as compared with gilteritinib and was associated with increased haematological toxicity. Although OS did not differ, a trend towards better survival was suggested with gilt-ven and a survival benefit was shown for gilt-ven approach when sequenced early for salvage.

The effect of mind-body intervention on lymphocyte doubling time and treatment free survival in treatment-naïve chronic lymphocytic leukemia patients.

INTRODUCTION: Mind-Body Intervention (MBI) serves as supportive aid in oncology. We hypothesized that MBI could impact the progression of Chronic Lymphocytic Leukemia (CLL) in the 'watch and wait' (w&w) phase. METHODS: MBI was utilized in a non-randomized prospective controlled study between 02/2020-02/2022 in 76 treatment-naïve CLL patients in the w&w phase (37 intervention and 39 control patients). The primary and secondary endpoints were prolongation of Lymphocyte Doubling Time (LDT) and treatment-free survival (TFS). The prolongation of LDT was compared at 0, 180, 360, and 540 days using paired t-tests. TFS was compared between intervention and control groups using the log-rank test. Cox proportional hazards models were used to calculate the hazard ratio (HR) and 95% confidence interval (CI) for TFS in the intervention group compared to the control, stratified by the study covariates. RESULTS: MBI prolonged LDT at all time points, including at day 360 (Median of 2.47 years; CI 1.05-3.9; p= 0.001). TFS at 18 months was longer in the intervention group compared to the control group (HR 0.23; CI 0.06-0.79, p=0.01). CONCLUSIONS: MBI was associated with prolonged LDT and TFS in patients with CLL in the w&w phase. These results provide a basis for a larger randomized-control trial.

The Effect of Oral Iron Chelator Deferiprone on Iron Overload and Oxidative Stress in Patients with Myelodysplastic Syndromes: A Study by the Israeli MDS Working Group.

BACKGROUND: Most patients with lower risk myelodysplastic neoplasms or syndromes (MDSs) become RBC transfusion-dependent, resulting in iron overload, which is associated with an increased oxidative stress state. Iron-chelation therapy is applied to attenuate the toxic effects of this state. Deferiprone (DFP) is an oral iron chelator, which is not commonly used in this patient population, due to safety concerns, mainly agranulocytosis. The purpose of this study was to assess the effect of DFP, on oxidative stress parameters in iron-overloaded RBC transfusion-dependent patients with lower risk MDSs. METHODS: Adult lower risk MDS patients with a cumulative transfusion burden of >20 red blood cell units and evidence of iron overload (serum ferritin >1,000 ng/mL) were included in this study. DFP was administered (100 mg/kg/day) for 4 months. Blood samples for oxidative stress parameters and iron overload parameters were done at baseline and monthly: reactive oxygen species (ROS), phosphatidylserine, reduced glutathione, membrane lipid peroxidation, serum ferritin, and cellular labile iron pool. The primary efficacy variable was ROS. Tolerability and side effects were recorded as well. A paired t test was applied for statistical analyses. RESULTS: Eighteen patients were treated with DFP. ROS significantly decreased in all cell lineages: median decrease of 58.6% in RBC, 33.3% in PMN, and 39.8% in platelets (p < 0.01 for all). Other oxidative stress markers improved: phosphatidylserine decreased by 57.95%, lipid peroxidase decreased by 141.3%, and reduced gluthathione increased by 72.8% (p < 0.01 for all). The iron-overload marker and cellular labile iron pool decreased by 35% in RBCs, 44.3% in PMN, and 46.3% in platelets (p < 0.01 for all). No significant changes were observed in SF levels. There were no events of agranulocytosis. All AEs were grades 1-2. CONCLUSIONS: Herein, we showed preliminary evidence that DFP decreases iron-induced oxidative stress in MDS patients with a good tolerability profile (albeit a short follow-up period). No cases of severe neutropenia or agranulocytosis were reported. The future challenge is to prove that reduction in iron toxicity will eventually be translated into a clinically meaningful improvement.

Cusatuzumab plus azacitidine in newly diagnosed acute myeloid leukaemia ineligible for intensive chemotherapy (CULMINATE): part one of a randomised, phase 2, dose optimisation study.

BACKGROUND: Cusatuzumab, a high-affinity anti-CD70 antibody, has shown preliminary activity as a treatment for acute myeloid leukaemia when combined with azacitidine. We aimed to determine the optimum dose for future trials of cusatuzumab in combination with azacitidine in patients with previously untreated acute myeloid leukaemia who are not eligible for intensive chemotherapy. METHODS: In this randomised, phase 2, open-label, dose-optimisation study we enrolled adult patients aged 18 years or older with newly diagnosed acute myeloid leukaemia not eligible for intensive chemotherapy, and with Eastern Cooperative Oncology Group scores of 0-2, from 40 hospitals and centres across seven countries. In part one of the trial, participants were randomly allocated 1:1 to 10 mg/kg or 20 mg/kg intravenous cusatuzumab on days 3 and 17, combined with subcutaneous or intravenous azacitidine 75 mg/m2 on days 1-7 in 28-day cycles. The primary efficacy outcome was the rate of complete remission in the intention-to-treat group. The two dose cohorts were evaluated independently without between-cohort statistical comparison. Safety analyses were performed in all patients who received one dose of study drug. Part two of the trial was planned to be a single-arm expansion to evaluate cusatuzumab plus azacitidine at the cusatuzumab dose level selected in part one (primary hypothesis ≥35% rate of complete remission vs null hypothesis of 20%); however, changes in the acute myeloid leukaemia treatment landscape during this trial made it unlikely that enrolment to part two of the study would be clinically feasible, so the study stopped at the end of part one. The trial was registered at ClinicalTrials.gov, NCT04023526. FINDINGS: 103 patients were enrolled between Aug 30, 2019, and Feb 25, 2020, and randomly assigned to either cusatuzumab 10 mg/kg (n=51) or 20 mg/kg (n=52). Median follow-up was 7·2 months (IQR 10·7 months). 57 of 103 (55%) patients were male and 46 (45%) patients were female, 78 (76%) were White, one (1%) was Asian, and 24 (23%) did not report their race. In the 10 mg/kg group, complete remission rate was 12% (six of 51 patients; 95% CI 6-23) and in the 20 mg/kg group was 27% (14 of 52; 17-40). Grade 3 or worse treatment-emergent adverse events (TEAEs) were similar between the cusatuzumab 10 mg/kg (n=51) and 20 mg/kg (n=51) cohorts and included thrombocytopenia (24 patients [47%] vs 29 [57%]), anaemia (24 [47%] vs 17 [33%]), and neutropenia (20 [39%] in both cohorts). Serious TEAEs were also similar in the two cohorts (44 [86%] vs 40 [78%]). Treatment-related TEAEs leading to death were reported in both groups (three patients [6%] in the 10 mg/kg group vs one patient [2%] in the 20 mg/kg group); the reported causes of death were pneumonia (n=2) and septic shock (n=2). INTERPRETATION: Although part one of this study was not designed to formally compare the two dose cohorts for efficacy, the totality of clinical data for cusatuzumab studies performed to date indicate that cusatuzumab 20 mg/kg plus azacitidine represents the optimal dose for further studies. A phase 1b study investigating the triple combination of cusatuzumab with venetoclax and azacitidine is underway (NCT04150887). FUNDING: Janssen Research & Development and argenx.

Decreased melanoma CSF-1 secretion by Cannabigerol treatment reprograms regulatory myeloid cells and reduces tumor progression.

During solid tumor progression, the tumor microenvironment (TME) evolves into a highly immunosuppressive milieu. Key players in the immunosuppressive environment are regulatory myeloid cells, including myeloid-derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs), which are recruited and activated via tumor-secreted cytokines such as colony-stimulating factor 1 (CSF-1). Therefore, the depletion of tumor-secreted cytokines is a leading anticancer strategy. Here, we found that CSF-1 secretion by melanoma cells is decreased following treatment with Cannabis extracts. Cannabigerol (CBG) was identified as the bioactive cannabinoid responsible for the effects. Conditioned media from cells treated with pure CBG or the high-CBG extract reduced the expansion and macrophage transition of the monocytic-MDSC subpopulation. Treated MO-MDSCs also expressed lower levels of iNOS, leading to restored CD8+ T-cell activation. Tumor-bearing mice treated with CBG presented reduced tumor progression, lower TAM frequencies and reduced TAM/M1 ratio. A combination of CBG and αPD-L1 was more effective in reducing tumor progression, enhancing survival and increasing the infiltration of activated cytotoxic T-cells than each treatment separately. We show a novel mechanism for CBG in modulating the TME and enhancing immune checkpoint blockade therapy, underlining its promising therapeutic potential for the treatment of a variety of tumors with elevated CSF-1 expression.

Venetoclax-based salvage therapy for adult patients with relapsed/refractory acute lymphoblastic leukemia.

OBJECTIVES: Dysregulation of BCL-2 family members has been reported in acute lymphocytic leukemia (ALL), with various BH3-dependencies of the leukemic clone. We conducted a multicenter retrospective cohort of patients with relapsed/refractory B or T ALL, with ven-chemotherapy or ven-navitoclax combinations, to assess efficacy and safety. METHODS: Seventeen patients were included in the analysis, median age was 32 years, with 6 B-ALL and 11 T-ALL patients. Nine patients received venetoclax combined with chemotherapy, and 13 patients received venetoclax in combination with navitoclax, vincristine and asparaginase, of which 5 were already exposed to venetoclax in previous lines. RESULTS: ORR was 55% and 46% among the ven-chemotherapy and the ven-navitoclax-chemotherapy, respectively. Most of the responders proceeded to an allogenic bone marrow transplant in both cohorts. The most common adverse effects of the ven-navitoclax combination were infectious complications and hepatotoxicity. CONCLUSIONS: Our data demonstrated the possible efficacy of ven-chemotherapy and ven-navitoclax in r/r ALL with moderate toxicity.

The increasingly blurred line between induction, consolidation and maintenance in acute myeloid leukaemia.

Since the early 1970s, the treatment of acute myeloid leukaemia (AML) has undergone a major transformation. Initially based on only two drugs, an anthracycline and cytosine arabinoside, the aim of therapy was to achieve a haematological response allowing patients to recover and go home. Back in those early days, cure was not a realistic expectation. Treatment was analogous to a heart attack; upon recovery and a short respite, recurrence and death inevitably followed. Over the subsequent decades, slow but remarkable progress was made such that a subgroup of young adults could become long-term survivors. This astonishing feat was achieved initially without the use of new drugs. Supportive care played a major role with the widespread availability of platelet transfusions and improved antimicrobial therapy, particularly antifungal. No less important was the better use of existing drugs and the development of allogeneic haematopoietic cell transplantation. While initially the focus was on maximal tolerated therapy, an understanding of the immunologic role of allogeneic transplantation, better genetic characterization of the biology of the disease, advanced tools for detection of minimal disease as well as the recent development of new drugs changed the focus to a more refined approach targeting patients who are more likely to respond. Clearly, the historical paradigm where the term AML was generic and applicable to all patients requires a rethinking from the traditional therapeutic demarcations of therapy into phases of induction, consolidation and maintenance. These evolving new concepts and paradigm will be herein considered.

Compromised activity of natural killer cells in diffuse large b-cell lymphoma is related to lymphoma-induced modification of their surface receptor expression.

While natural killer (NK) cells are essential players in detection and elimination of malignant cells, these surveillance properties can be compromised by cancer cells. Since NK cell education primarily occurs in the bone marrow and lymphoid tissue, this process might be particularly affected by their infiltration with lymphoma cells. This study aimed to explore functional properties of diffuse large B-cell lymphoma (DLBCL) patient NK cells, which could potentially promote tumour immune evasion and disease propagation.NK cells isolated from the peripheral blood (PB) of 26 DLBCL patients and 13 age-matched healthy controls (HC) were analysed. The cytotoxic CD56dim subtype was the only one identified in patients. Compared to HC, patient cells demonstrated low levels of inhibitory CD158a/b along with decreased expression of activating NKG2D and CD161 and increased inhibitory NKG2A levels. Patient NK cell cytotoxic activity was impaired, as were their degranulation and inflammatory cytokine production, which partially recovered following non-receptor-dependant stimulation.The phenotypically skewed and restricted population of patient NK cells, along with their blunted cytotoxic and immune-regulatory activity, appear to be driven by exposure to lymphoma environment. These NK cell functional aberrations could support lymphoma immune evasion and should be considered in the era of cellular therapy.

Implementation of data protection laws in the European Union and in California is associated with a move of clinical trials to countries with fewer data protections.

The European Union implemented data privacy laws in mid-2018 and the state of California enacted a similar law several weeks later. These regulations affect medical data collection and analysis. It is unclear if they achieve this goal in the realm of clinical trials. Here we investigate the effect of these laws on clinical trials through analysis of clinical trials recorded on the US's ClinicalTrials.gov, the World Health Organization's International Clinical Trials Registry Platform and scientific papers describing clinical trials. Our findings show that the number of phase 1 and 2 trials in countries not adhering to these data privacy laws rose significantly after implementation of these laws. The largest rise occurred in countries which are less free, as indicated by the negative correlation (-0.48, p = 0.008) between the civil liberties freedom score of countries and the increase in the number of trials. This trend was not observed in countries adhering to data privacy laws nor in the paper publication record. The rise was larger (and statistically significant) among industry funded trials and interventional trials. Thus, the implementation of data privacy laws is associated a change in the location of clinical trials, which are currently executed more often in countries where people have fewer protections for their data.

Re-induction versus salvage for D14-resiudal acute myeloid leukemia: A retrospective multi-center study.

Remission assessment in acute myeloid leukemia has evolved over the recent years with the advent of molecular and flow-based minimal residual disease determination. Nonetheless, early time point such as day 5 and day 14 (D14), still have prognostic and therapeutic implications. D14 refractory disease is regarded as a poor prognostic factor, however the therapeutic intervention is still under debate, with evidence suggesting a successful re-induction might offer similar long-term outcome as D14 aplasia. Others advocate the use of more intensive salvage protocols as a mean to overcome the negative prognostic effect. In the current study, we compare outcome of D14 refractory AML patients treated with either re-induction or salvage protocol. More importantly, we identify response characteristics that might suggest which patients will benefit from re-induction approach. Accurate identification of chemotherapy refractory patients might allow the early incorporation of non-chemotherapy based protocols in the future.

Venetoclax in combination with FLAG-IDA-based protocol for patients with acute myeloid leukemia: a real-world analysis.

Venetoclax in combination with intensive therapies is explored in both the upfront and relapse/refractory (R/R) setting, and available data suggest that such regimens are effective albeit with added hematological and infectious toxicity. We conducted a multicenter retrospective cohort study of patients with acute myeloid leukemia (AML) treated with venetoclax in combination with FLAG-IDA protocol. Twenty-five patients were included in this analysis (median age 53.4 years). Most patients were treated for R/R AML (n = 24, 96%) with a median of one (range 0-3) previous lines of therapy and 44% of patients (n = 11) having prior allogeneic hematopoietic cell transplantation (HCT). Median follow-up was 10 (range, 4-26) months. Platelet and neutrophil recovery were observed at a median of 31 (95% CI 17.6-38.3) and 23 (95% CI 20-28) days, respectively. The most common adverse events were infectious (blood stream infections, 48% and invasive fungal infections, 32%). Thirty-day mortality was 12%. Composite complete remission (CRc) was 72% for the entire cohort and 91% in patients treated for post-HCT relapse. Incidences of relapse-free and overall survival at 12 months were 67% (95% CI 58-76%) and 50% (95% CI 31-69%), respectively. Real-world data show that the addition of venetoclax to FLAG-IDA protocol is effective in patients with high-risk AML, most notably in the post-HCT relapse setting. Prophylaxis and surveillance for infections are crucial.

Gilteritinib monotherapy for relapsed/refractory FLT3 mutated acute myeloid leukemia: a real-world, multi-center, matched analysis.

Patients with FLT3-mutated relapsed or refractory (R/R) acute myeloid leukemia (AML) have a dismal prognosis. Gilteritinib is a FLT3 tyrosine kinase inhibitor (TKI) recently approved for patients with R/R AML. We aimed to characterize real-world data regarding gilteritinib treatment in FLT3-mutated R/R AML and to compare outcomes with matched FLT3-mutated R/R AML patients treated with chemotherapy-based salvage regimens. Twenty-five patients from six academic centers were treated with gilteritinib for FLT3-mutated R/R AML. Eighty percent were treated with a prior intensive induction regimen and 40% of them received prior TKI therapy. Twelve patients (48%) achieved complete response (CR) with gilteritinib. The estimated median overall survival (OS) of the entire cohort was eight (CI 95% 0-16.2) months and was significantly higher in patients who achieved CR compared to those who did not (16.3 months, CI 95% 0-36.2 vs. 2.6 months, CI 95% 1.47-3.7; p value = 0.046). In a multivariate cox regression analysis, achievement of CR was the only predictor for longer OS (HR 0.33 95% CI 0.11-0.97, p = 0.044). Prior TKI exposure did not affect OS but was associated with better event-free survival (HR 0.15 95% CI 0.03-0.71, p = 0.016). An age and ELN-risk matched comparison between patients treated with gilteritinib and intensive salvage revealed similar response rates (50% in both groups); median OS was 9.6 months (CI 95% 2.3-16.8) vs. 7 months (CI 95% 5.1-8.9) in gilteritinib and matched controls, respectively (p = 0.869). In conclusion, in the real-world setting, gilteritinib is effective, including in heavily pre-treated, TKI exposed patients.