Abstract Background Acute myeloid leukemia (AML) is predominantly a disease of older patients with a poor long-term survival. Approval of the combination of venetoclax (VEN) with azacitidine (AZA) or decitabine (DAC) in the European Union in 2021 for the treatment of patients with newly diagnosed AML who are ineligible for induction chemotherapy has become the treatment backbone for older, medically non-fit AML patients. Based on in vitro priming of AML cells to all- trans retinoic acid (ATRA) by DAC, we had previously conducted a randomized phase II trial (DECIDER, AMLSG 14 − 09) in 200 elderly, non-fit AML patients on the effect of ATRA as add-on to DAC. Median overall survival (OS) was 8.2 months with ATRA versus 5.1 months without ATRA (hazard ratio, 0.65; 95% CI, 0.48 to 0.89; P = 0.006). Notably, ATRA did not add toxicity, the combination was active also in patients with adverse genetics, and prolonged time to treatment resistance. Investigating a triple combination of DAC, VEN and ATRA was a logical next step. This randomized double-blind phase III trial compares the efficacy of ATRA versus placebo as add-on to the backbone treatment (DAC and VEN) with respect to OS, objective best response, quality of life and safety. The accompanying translational research will contribute to identify molecular markers for drug efficacy and better tailoring epigenetic therapy. Methods DECIDER-2 (AMLSG 32 − 21) is a prospective, randomized, double-blind, placebo-controlled, parallel group, multicenter trial. The primary study objective is to compare the efficacy of ATRA versus placebo as add-on to the backbone treatment (DAC and VEN) in terms of OS. The target population is adult AML patients unfit for standard induction chemotherapy. Patients are randomized (1:1) to receive backbone treatment in combination with either ATRA or placebo. Four interim safety analyses were planned with the involvement of the Data Monitoring Committee. Discussion This trial investigates whether the in vitro cooperativity of DAC, VEN, and ATRA prolongs OS in unfit AML patients compared to placebo, offering a novel, low-toxicity triplet combination with a promising risk-benefit ratio. Clinical trial number EU CT number: 2020-005495-36/2023-507461-26-00 (registered 18.11.2020); German clinical trials registry number: DRKS00023646 (registered 23.08.2022).

​Background:Synchronous oligometastatic non–small cell lung cancer (sOMD) is a heterogeneous stage IV subgroup where multimodal treatment may improve outcomes.Methods:Patients with sOMD (≤5 metastases in ≤3 organs) diagnosed between July 2015 and May 2020 at five BZKF centers were retrospectively analyzed. All received systemic therapy with or without local ablative treatment (surgery or radiotherapy); those with local therapy alone were excluded. Progression-free survival (PFS) and overall survival (OS) were assessed using Kaplan–Meier analysis, with multivariable Cox regression for prognostic factors.Results:Among 293 patients (median follow-up 33.5 months), 74% received combined systemic and local therapy. Median PFS was 9.9 months overall and significantly longer with combined therapy than systemic therapy alone (10.2 vs. 8.4 months, p=0.02). Median OS was 26.4 months, with a trend favoring combined therapy (31.1 vs. 20.0 months). Surgery as local treatment was associated with better PFS and OS than radiotherapy. Omission of local therapy increased risks of progression (HR 1.55) and death (HR 1.52). Poor ECOG status and older age were also linked to worse outcomes.Conclusion:Combining systemic therapy with local ablative treatment improves outcomes in selected patients with sOMD compared to systemic therapy alone. These findings support integrating local treatments into care strategies and highlight the need for prospective studies on optimal sequencing and patient selection.

BACKGROUND:Synchronous oligometastatic non-small cell lung cancer (sOMD) is a heterogeneous subgroup of stage IV disease in which multimodal treatment may improve outcomes. METHODS:Patients with sOMD (≤5 metastases in ≤ 3 organs) diagnosed between July 2015 and May 2020 at five lung cancer centers were retrospectively analyzed. Patients receiving systemic therapy alone or multimodal therapy consisting of systemic therapy plus local treatment (surgery and/or radiotherapy) were included; those treated with local therapy alone were excluded. Progression-free survival (PFS) and overall survival (OS) were analyzed using the Kaplan-Meier method according to treatment modality and treatment sequence. Multivariable Cox regression identified independent prognostic factors. RESULTS:Among 293 patients (median follow-up, 33.5 months), 74% received multimodal therapy. Median PFS was 9.9 months overall and was significantly longer with multimodal therapy than with systemic therapy alone (10.2 vs. 8.4 months; p = 0.02). Median OS was 26.4 months and numerically favored multimodal therapy (31.1 vs. 20.0 months). Among patients receiving local treatment, surgery was associated with longer PFS and OS than radiotherapy. Complete local treatment of all metastatic lesions was associated with improved OS compared with incomplete treatment (31.6 vs. 16.3 months). In multivariable analysis, omission of local therapy independently predicted worse PFS (HR 1.55) and OS (HR 1.52). Older age and poorer ECOG performance status were also independently associated with inferior outcomes. CONCLUSIONS:Multimodal therapy combining systemic and local ablative treatment was associated with improved outcomes compared with systemic therapy alone. A sequential approach, with systemic therapy followed by local ablative treatment, appeared to provide the greatest benefit. Prospective studies are warranted to define the optimal treatment sequence and refine patient selection.

In a randomized phase II trial (AMLSG 14-09, NCT00867672) of elderly, newly diagnosed AML patients, ATRA combined with decitabine (DEC) significantly improved the overall response rate (ORR) and survival also in patients with adverse-risk genetics, without adding toxicity. We performed a post hoc analysis to determine the predictive impact of TP53 status. Despite a nominally higher ORR, the clinically meaningful survival benefit when adding ATRA to DEC was diminished, but not completely negated, in TP53-mutated patients. Indeed, 2 out of 14 TP53-mutated patients (14%) randomized to a DEC + ATRA-containing regimen lived for > 36 months. Further studies of ATRA combined with hypomethylating agents appear warranted in non-M3 AML patients ineligible for HMA/venetoclax therapy. Trial Registration: ClinicalTrials.gov identifier: NCT00867672

BACKGROUND:The efficacy of checkpoint inhibitors for non-small cell lung cancer (NSCLC) with MET exon 14 skipping (METΔ14ex) remains controversial. MATERIALS AND METHODS:110 consecutive METΔ14ex NSCLC patients receiving first-line chemotherapy (CHT) and/or immunotherapy (IO) in 10 German centers between 2016-2022 were analyzed. RESULTS:Combined CHT-IO was given to 35/110 (32%) patients, IO alone to 43/110 (39%), and CHT to 32/110 (29%) upfront. Compared to CHT, CHT-IO showed longer progression-free survival (median PFS 6 vs. 2.5 months, p = 0.004), more objective responses (ORR 49% vs. 28%, p = 0.086) and numerically longer overall survival (OS 16 vs. 10 months, p = 0.240). For IO monotherapy, OS (14 vs. 16 months) and duration of response (26 vs. 22 months) were comparable to those of CHT-IO. Primary progressive disease (PD) was more frequent with IO compared to CHT-IO (13/43 vs. 3/35, p = 0.018), particularly for never-smokers (p = 0.041). Higher PD-L1 TPS were not associated with better IO outcomes, but TP53 mutated tumors showed numerically improved ORR (56% vs. 32%, p = 0.088) and PFS (6 vs. 3 months, p = 0.160), as well as longer OS in multivariable analysis (HR=0.54, p = 0.034) compared to their wild-type counterparts. Any second-line treatment was administered to 35/75 (47%) patients, with longer survival for capmatinib or tepotinib compared to crizotinib (PFS 10 vs. 3 months, p = 0.013; OS 16 vs. 13 months, p = 0.270). CONCLUSION:CHT-IO is superior to CHT, and IO alone also effective for METΔ14ex NSCLC, especially in the presence of TP53 mutations and independent of PD-L1 expression, but never-smokers are at higher risk of primary PD.

BackgroundIn selected patients with early-stage malignant pleural mesothelioma (MPM), a multimodal therapy that includes surgical cytoreduction, chemotherapy, and/or radiotherapy is recommended. Several clinical trials have demonstrated the beneficial effects of immune checkpoint inhibitors in pretreated MPM patients with advanced disease. Recent clinical data have suggested that the combination of chemotherapy and checkpoint inhibition might improve efficacy.Trial DesignThe NICITA (nivolumab with chemotherapy in pleural mesothelioma after surgery) trial is a prospective, 1:1 randomized, open-label, multicenter phase II clinical trial (ClinicalTrials.gov identifier, NCT04177953). Ninety-two patients with MPM epithelioid subtype, who had undergone extended pleurectomy and decortication with or without hyperthermic intrathoracic chemoperfusion, will be included to receive adjuvant treatment. All patients will receive ≤ 4 cycles of platinum-based chemotherapy with pemetrexed (arms A and B). Patients in arm B will additionally receive nivolumab, together with the adjuvant chemotherapy, and subsequently for ≤ 12 cycles as maintenance therapy. The primary endpoint of this study is the time-to-next-treatment. The secondary endpoints include progression-free survival, overall survival, proportion of patients with treatment beyond progression, duration of treatment beyond progression in this population, and quality of life.ConclusionThis prospective trial will contribute data to assess the efficacy of standard chemotherapy combined with nivolumab in the context of multimodal management of early-stage MPM. The study is currently enrolling patients.

Background EGFR exon20 insertions (ex20ins) are targeted by novel compounds in non-small-cell lung cancer (NSCLC). However, data about outcome under conventional therapies and the influence of molecular features are scarce. Patients and methods We retrospectively analysed 118 patients with evaluation of radiologic response based on RECIST v1.1. TP53 status was available for 88 cases. Results Platinum doublets and chemoimmunotherapy showed similar response rates (20–25%), disease control rates (80%) and median progression-free survival (mPFS, ≈7 months), which were longer compared to monochemotherapy (9%, 59%, 4.1 months), EGFR inhibitors (0%, 46%, 3.0) and PD-(L)1 inhibitors (0%, 30%, 2.1; p < 0.05). Overall survival (OS) was not dependent on the choice of first-line treatment, but related to more lines of systemic therapy (p < 0.05). TP53 mutations and brain metastases were associated with shorter PFS under platinum doublets and EGFR inhibitors (HR 3.3–6.1, p < 0.01), and shorter OS for patients receiving both treatments (p < 0.05). More tumour CD8+ and less Th1 cells were associated with longer OS independent of brain and TP53 status (p < 0.01). No difference in outcome was noted according to the ex20ins site and use of pemetrexed (vs. other cytotoxics) or bevacizumab. Long-lasting responses (>1 year) occasionally occurred under EGFR inhibitors for both 'near-' and 'far-loop' variants. Conclusions Platinum doublets and chemoimmunotherapy have the highest activity with ORR of 20–25% and mPFS of approximately 7 months, regardless of the cytotoxic partner, while PD-(L)1 inhibitors show limited efficacy. TP53 mutations, brain metastases and a lower tumour CD8/Th1-cell ratio are independently associated with shorter survival.

2579 Background: In preclinical studies, the combination of anti-VEGF/Ang2 and anti-PD-1 therapy has been shown to promote an immunopermissive state, which is supportive of T-cell-mediated tumor cell destruction. BI 836880 is a humanized bispecific nanobody that targets VEGF and Ang2, and ezabenlimab (BI 754091) is an anti-PD-1 antibody. Phase I studies investigating each as monotherapies have reported safety and preliminary antitumor activity. This ongoing Phase Ib study is evaluating the combination of BI 836880 and ezabenlimab in pts with advanced solid tumors. In Part 1 (dose escalation), the combination was feasible in pts with advanced NSCLC, with a recommended Phase II dose (RP2D) of BI 836880 720 mg + ezabenlimab 240 mg IV q3w. Here, we report updated results from Part 2 (expansion phase), which is assessing the antitumor activity and safety of the RP2D. Methods: Seven cohorts are currently recruiting pts in Part 2: metastatic (m) NSCLC after checkpoint inhibitor (CPI) monotherapy (Cohort A); mNSCLC after chemotherapy (CT) + CPI (Cohort B); mSCLC after CT ± CPI (Cohort C); 1st and 2nd recurrences of glioblastoma (GBM; Cohort D); immunotherapy-resistant m-melanoma (Cohort E); hepatocellular carcinoma (HCC) after prior sorafenib or lenvatinib ± CPI (Cohort F); and previously untreated/unresectable HCC (Cohort G). Primary endpoint is objective response rate (complete response + partial response [PR]). Results: As of January 2021, 196 pts have received BI 836880 plus ezabenlimab (14 in Part 1, 182 in Part 2 [Cohort A, 26; B, 30; C, 19; D, 31; E, 32; F, 28; G, 16]). 134 (68%) pts were male, median age was 63 years and 102 (52%) had prior CPI use. Any grade and ≥G3 adverse events (AEs; any cause) were reported by 160 (82%) and 62 (32%) pts, most commonly (all%/≥G3%) hypertension (20/8), asthenia (20/3), diarrhea, decreased appetite, and nausea (all 11/1). 95 (48%) pts had a drug-related AE, most commonly hypertension and asthenia (both 11%). 6 pts had a G4 AE (non-related: hyperkalemia + cardiac arrest, laryngospasm, gastrointestinal perforation; drug-related: anaphylactic reaction, acute pancreatitis, transaminases increased); 8 pts had a G5 AE (non-related: general physical health deterioration, epilepsy, hemoptysis, cardio-respiratory arrest, hepatic failure, intracranial hemorrhage, COVID-19 pneumonia; drug-related tracheal hemorrhage). 30 (15%) pts had immune-related AEs (3% ≥G3), including hypothyroidism (3%). 11 (6%) pts had an AE leading to discontinuation. Overall, 145 pts were evaluable for response: 9 pts achieved confirmed PR (2 pts in Part 1 and 7 in Part 2 [NSCLC, n = 3; SCLC, n = 1; GBM, n = 1; melanoma, n = 1; and 2nd-line HCC, n = 1]), 87 pts had stable disease and 49 pts had progressive disease. 111 pts remain on treatment. Conclusions: BI 836880 plus ezabenlimab had a manageable safety profile. The combination showed preliminary antitumor activity in a range of tumor types. Clinical trial information: NCT03468426.

Abstract Background Platinum‐based chemotherapy remains a first‐line standard of care for approximately 30% of patients with non‐small cell lung cancer (NSCLC) not harboring a druggable alteration. Favorable efficacy and safety of the nab‐paclitaxel/carboplatin (nab‐P/C) combination was shown in the pivotal phase 3 trial. However, information on effectiveness of nab‐P/C in a real‐world setting in Germany is missing. The NEPTUN study prospectively investigated the effectiveness and safety of nab‐P/C in patients with advanced NSCLC in a real‐world setting. Methods Patients with advanced or metastatic NSCLC received first‐line nab‐P/C according to clinical routine. The primary endpoint was 6‐month progression‐free survival rate (PFS6). Other endpoints included further effectiveness parameters, safety and quality of life. Data were analyzed descriptively. Results 408 patients were enrolled. PFS6 was 40.8% (95% confidence interval [CI], 35.3–46.2); median PFS was 5.2 months (95% CI, 4.5–5.7). overall response rate was 41.5% (95% CI, 36.3–46.8). Median overall survival (OS) was 10.5 months (95% CI, 9.2–11.6). Subgroup analyses revealed median OS for squamous versus non‐squamous histology (11.8 months [95% CI, 9.2–13.8] vs. 9.6 months [95% CI, 7.7–11.2]) and age ≥70 versus <70 years (11.7 months [95% CI, 9.4–14.3] vs. 9.6 months [95% CI, 7.5–11.2]). Most common treatment‐emergent adverse events (TEAEs) were anemia (26.5%), leukopenia (25.7%), and thrombocytopenia (16.6%). Mostly reported grade 3/4 TEAEs were leukopenia (10.2%), anemia (8.6%), and pneumonia (5.1%). nab‐paclitaxel‐related deaths as reported by the investigator occurred in 0.8% of patients. Conclusion These real‐world data support the effectiveness and safety of nab‐P/C as first‐line treatment for patients with advanced NSCLC independent of tumor histology. The results are comparable with the pivotal phase 3 trial. No new safety signals emerged.

Lenalidomide is an integral, yet evolving, part of current treatment pathways for both transplant-eligible and transplant-ineligible patients with newly diagnosed multiple myeloma (NDMM). It is approved in combination with dexamethasone as first-line therapy for transplant-ineligible patients with NDMM, and as maintenance treatment following autologous stem cell transplantation (ASCT). Although strong clinical trial evidence has supported the integration of lenalidomide into current treatment paradigms for NDMM, applying those paradigms to individual patients and determining which patients are most likely to benefit from lenalidomide treatment are more complex. In this paper, we utilize the available clinical trial evidence to provide recommendations for patient selection and lenalidomide dosing in both the first-line setting in patients ineligible for ASCT and the maintenance setting in patients who have undergone ASCT. In addition, we provide guidance on management of those adverse events that are most commonly associated with lenalidomide treatment, and consider the optimal selection and sequencing of next-line agents following long-term frontline or maintenance treatment with lenalidomide.

PURPOSE DNA-hypomethylating agents are studied in combination with other epigenetic drugs, such as histone deacetylase inhibitors or differentiation inducers (eg, retinoids), in myeloid neoplasias. A randomized, phase II trial with a 2 x 2 factorial design was conducted to investigate the effects of the histone deacetylase inhibitor valproate and all-trans retinoic acid (ATRA) in treatment-naive elderly patients with acute myeloid leukemia (AML). PATIENTS AND METHODS Two hundred patients (median age, 76 years; range, 61-92 years) ineligible for induction chemotherapy received decitabine (20 mg/m(2) intravenously, days 1 to 5) alone (n = 47) or in combination with valproate (n = 57), ATRA (n = 46), or valproate + ATRA (n = 50). The primary endpoint was objective response, defined as complete and partial remission, tested at a one-sided significance level of alpha = .10. Key secondary endpoints were overall survival, event-free survival, and progression-free survival and safety. RESULTS The addition of ATRA resulted in a higher remission rate (21.9% with ATRA v 13.5% without ATRA; odds ratio, 1.80; 95% CI, 0.86 to 3.79; one-sided P = .06). For valproate, no effect was observed (17.8% with valproate v 17.2% without valproate; odds ratio, 1.06; 95% CI, 0.51 to 2.21; one-sided P = .44). Median overall survival was 8.2 months with ATRA v 5.1 months without ATRA (hazard ratio, 0.65; 95% CI, 0.48 to 0.89; two-sided P = .006). Improved survival was observed across risk groups, including patients with adverse cytogenetics, and was associated with longer response duration. With valproate, no survival difference was observed. Toxicities were predominantly hematologic, without relevant differences between the 4 arms. CONCLUSION The addition of ATRA to decitabine resulted in a higher remission rate and a clinically meaningful survival extension in these patients with difficult-to-treat disease, without added toxicity. (C) 2019 by American Society of Clinical Oncology

9566 Background: Preclinical studies show that combining anti-VEGF/Ang2 with anti-PD-1 therapy promotes an immunopermissive state supportive of T-cell-mediated tumor cell destruction. BI 836880 is a humanized bispecific nanobody that targets VEGF and Ang2, and BI 754091 is an anti-PD-1 antibody. Each has shown manageable safety and preliminary activity as monotherapy. Here, we report initial results from a Phase Ib study assessing BI 836880 in combination with BI 754091. Methods: In Part 1 (dose escalation), pts with locally advanced or metastatic (m) non-squamous NSCLC who progressed during/after completion of ≥2 cycles of platinum-based chemotherapy (CT) ± a checkpoint inhibitor (CPI) were enrolled. Pts received BI 836880 (cohorts of 360, 500 and 720 mg intravenously [iv] 3-weekly [q3w]) plus fixed-dose BI 754091 (240 mg iv q3w). Dose escalation was guided by Bayesian logistic regression models with overdose control. Primary endpoint in Part 1 was maximum tolerated dose (MTD)/recommended phase 2 dose (RP2D), based on dose-limiting toxicities (DLTs) in Cycle 1. Initial safety and efficacy results of Part 1 are reported here. Part 2 will assess safety and efficacy in 6 expansion cohorts: mNSCLC after CPI monotherapy; mNSCLC after CT + CPI; mSCLC after CT ± CPI; immunotherapy-resistant m-melanoma; recurrent glioblastoma after 1st-line CT; and hepatocellular carcinoma after prior sorafenib or lenvatinib ± subsequent CPI. Results: 12 pts received BI 836880 plus BI 754091 (8 male; median age 59.5 years; 8 had received prior CPI). 4 pts remain on treatment (including 1 treated for 15 cycles). 1 pt had a DLT during Cycle 1 (360 mg; G3 pulmonary embolism). All pts experienced an adverse event (AE; any-cause; safety data cut-off Nov 2019), most commonly (all%/G3%) hypertension (58/25), vomiting (42/0), nausea (33/0), and asthenia (33/0). Hypertension was transient. No G4 AEs were reported; one G5 AE occurred (general physical health deterioration). 5 pts had immune-related AEs (G2 hypothyroidism in 2 pts; G2 pruritus, G1 papular rash, and G2 vomiting). To date (Jan 2020), 2 pts have achieved partial response; 1 pt (500 mg dose; CPI-naïve) had 58% target lesion reduction, and 1 (720 mg; prior CPI) had 35% target lesion reduction. 8 pts had stable disease. Conclusions: MTD/RP2D was BI 836880 720 mg plus BI 754091 240 mg q3w. The combination had a manageable safety profile, and preliminary anti-tumor activity was observed. Expansion cohorts are ongoing. Equal contribution: JA and BH Clinical trial information: NCT03468426 .

DNA methylation differences between normal tissue and cancerous tissue resulting in differential expression of genes are a hallmark of acute myeloid leukemia (AML) and can provide malignant cells with a growth advantage via silencing of specific genes, for example, transcription factors. Oligodendrocyte lineage transcription factor 2 (OLIG2) was reported to be differentially methylated and associated with prognosis in AML and, as reported for acute lymphoblastic leukemia and malignant glioma, may play a role in malignant transformation. We report that DNA methylation of OLIG2 is associated with decreased expression of mRNA in AML cell lines and patients. Moreover, in cell lines, decreased mRNA expression also translated into decreased OLIG2 protein expression. Treatment of non-expressing cell lines PL-21 and U-937 with the demethylating agent decitabine resulted in robust re-expression of OLIG2 on mRNA and protein levels. Furthermore, stable overexpression of OLIG2 in non-expressing cell lines Kasumi-1 and U-937, using a lentiviral vector system, led to moderate growth inhibition after 4 days and resulted in signs of differentiation in U-937 cells. Interestingly, although CD34 + cells from healthy donors and 10 of 12 AML patients exhibited no protein expression, OLIG2 was expressed in two patients, both bearing the translocation t(15;17), corresponding to OLIG2 expression in NB-4 cells, also harboring t(15;17). In conclusion, we provide first evidence that OLIG2 is epigenetically regulated via DNA methylation and expressed in a subset of AML patients. OLIG2 may exert antiproliferative activity in leukemia cell lines, and its potential leukemia-suppressing role in AML warrants further investigation. (C) 2017 ISEH Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.

Acute myeloid leukemia (AML) is primarily a disease of older patients with a median age above 70 years. The outcome for these patients has not substantially improved over the last four decades and ...

Intratumoral genetic heterogeneity may impact disease outcome. Gold standard for dissecting clonal heterogeneity are single-cell analyses. Here, we present an efficient workflow based on an advanced Single-Cell Printer (SCP) device for the study of gene variants in single cancer cells. To allow for precise cell deposition into microwells the SCP was equipped with an automatic dispenser offset compensation, and the 384-microwell plates were electrostatically neutralized. The ejection efficiency was 99.7% for fluorescent beads (n = 2304) and 98.7% for human cells (U-2 OS or Kasumi-1 cancer cell line, acute myeloid leukemia [AML] patient; n = 150). Per fluorescence microscopy, 98.8% of beads were correctly delivered into the wells. A subset of single cells (n = 81) was subjected to whole genome amplification (WGA), which was successful in all cells. On empty droplets, a PCR on LINE1 retrotransposons yielded no product after WGA, verifying the absence of free-floating DNA in SCP-generated droplets. Representative gene variants identified in bulk specimens were sequenced in single-cell WGA DNA. In U-2 OS, 22 of 25 cells yielded results for both an SLC34A2 and TET2 mutation site, including cells harboring the SLC34A2 but not the TET2 mutation. In one cell, the TET2 mutation analysis was inconclusive due to allelic dropout, as assessed via polymorphisms located close to the mutation. Of Kasumi-1, 23 of 33 cells with data on both the KIT and TP53 mutation site harbored both mutations. In the AML patient, 21 of 23 cells were informative for a TP53 polymorphism; the identified alleles matched the loss of chromosome arm 17p. The advanced SCP allows efficient, precise and gentle isolation of individual cells for subsequent WGA and routine PCR/sequencing-based analyses of gene variants. This makes single-cell information readily accessible to a wide range of applications and can provide insights into clonal heterogeneity that were indeterminable solely by analyses of bulk specimens.

The common γ chain (CD132) is a subunit of the interleukin (IL) receptors for IL-2, IL-4, IL-7, IL-9, IL-15, and IL-21. Because levels of several of these cytokines were shown to be increased in the serum of patients developing acute and chronic graft-versus-host disease (GVHD), we reasoned that inhibition of CD132 could have a profound effect on GVHD. We observed that anti-CD132 monoclonal antibody (mAb) reduced acute GVHD potently with respect to survival, production of tumor necrosis factor, interferon-γ, and IL-6, and GVHD histopathology. Anti-CD132 mAb afforded protection from GVHD partly via inhibition of granzyme B production in CD8 T cells, whereas exposure of CD8 T cells to IL-2, IL-7, IL-15, and IL-21 increased granzyme B production. Also, T cells exposed to anti-CD132 mAb displayed a more naive phenotype in microarray-based analyses and showed reduced Janus kinase 3 (JAK3) phosphorylation upon activation. Consistent with a role of JAK3 in GVHD, Jak3(-/-) T cells caused less severe GVHD. Additionally, anti-CD132 mAb treatment of established chronic GVHD reversed liver and lung fibrosis, and pulmonary dysfunction characteristic of bronchiolitis obliterans. We conclude that acute GVHD and chronic GVHD, caused by T cells activated by common γ-chain cytokines, each represent therapeutic targets for anti-CD132 mAb immunomodulation.

Introduction: Cytotoxic agents and ionizing radiotherapy in the treatment concept of most cancer types and non-malignant diseases bear a significant risk to develop therapy-related malignancies such as myelodysplasia (t-MDS) and acute myeloid leukemia (t-AML). The outcome of patients treated with low- or high-dose chemotherapy alone for t-MDS/AML remains poor. The only curative treatment option implements allogeneic hematopoietic stem cell transplantation (aHSCT). However, long-term follow-up data beyond 5 years of t-MDS/AML patients having received aHSCT is scarce.