ABSTRACT
Central nervous system (CNS) involvement remains a clinical hurdle in treating childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL). The disease mechanisms of CNS leukemia are primarily investigated using 2D cell culture and mouse models. Given the variations in cellular identity and architecture between the human and murine CNS, it becomes imperative to seek complementary models to study CNS leukemia. Here, we present a first-of-its-kind 3D co-culture model combining human brain organoids and BCP-ALL-cells. We noticed significantly higher engraftment of BCP-ALL cell lines and patient-derived xenograft (PDX) cells in cerebral organoids as compared to non-ALL-cells. To validate translatability between organoid co-culture and in vivo murine models, we confirmed that targeting CNS leukemia relevant pathways like CD79a/Igα or CXCR4-SDF1 reduced the invasion of BCP-ALL-cells into organoids. RNA sequencing and functional validations of organoid-invading leukemia cells compared to the non-invaded fraction revealed significant upregulation of AP-1 transcription factor-complex members in organoid-invading cells. Moreover, we detected a significant enrichment of AP-1 pathway genes in ALL-PDX-cells recovered from the CNS compared to spleen blasts of mice transplanted with TCF3::PBX1+ PDX-cells, substantiating the role of AP-1 signaling in CNS disease. Accordingly, we found significantly higher levels of the AP-1-gene JUN in patients initially diagnosed as CNS-positive compared to CNS-negative cases as well as CNS-relapse vs non-CNS-relapse cases in a cohort of 100 BCP-ALL-patients. Our results suggest CNS-organoids as a novel model to investigate CNS-involvement and identify the AP-1 pathway as a critical driver of CNS-disease in BCP-ALL.
ABSTRACT
ABSTRACT: The t(1;19) translocation, encoding the oncogenic fusion protein E2A (TCF3)-PBX1, is involved in acute lymphoblastic leukemia (ALL) and associated with a pre-B-cell receptor (preBCR+) phenotype. Relapse in patients with E2A-PBX1+ ALL frequently occurs in the central nervous system (CNS). Therefore, there is a medical need for the identification of CNS active regimens for the treatment of E2A-PBX1+/preBCR+ ALL. Using unbiased short hairpin RNA (shRNA) library screening approaches, we identified Bruton tyrosine kinase (BTK) as a key gene involved in both proliferation and dasatinib sensitivity of E2A-PBX1+/preBCR+ ALL. Depletion of BTK by shRNAs resulted in decreased proliferation of dasatinib-treated E2A-PBX1+/preBCR+ cells compared with control-transduced cells. Moreover, the combination of dasatinib with BTK inhibitors (BTKi; ibrutinib, acalabrutinib, or zanubrutinib) significantly decreased E2A-PBX1+/preBCR+ human and murine cell proliferation, reduced phospholipase C gamma 2 (PLCG2) and BTK phosphorylation and total protein levels and increased disease-free survival of mice in secondary transplantation assays, particularly reducing CNS-leukemic infiltration. Hence, dasatinib with ibrutinib reduced pPLCG2 and pBTK in primary ALL patient samples, including E2A-PBX1+ ALLs. In summary, genetic depletion and pharmacological inhibition of BTK increase dasatinib effects in human and mouse with E2A-PBX1+/preBCR+ ALL across most of performed assays, with the combination of dasatinib and BTKi proving effective in reducing CNS infiltration of E2A-PBX1+/preBCR+ ALL cells in vivo.
Subject(s)
Agammaglobulinaemia Tyrosine Kinase , Dasatinib , Protein Kinase Inhibitors , Dasatinib/therapeutic use , Dasatinib/pharmacology , Agammaglobulinaemia Tyrosine Kinase/antagonists & inhibitors , Agammaglobulinaemia Tyrosine Kinase/metabolism , Humans , Animals , Mice , Protein Kinase Inhibitors/therapeutic use , Protein Kinase Inhibitors/pharmacology , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Central Nervous System Neoplasms/drug therapy , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Oncogene Proteins, Fusion/genetics , Oncogene Proteins, Fusion/metabolism , Cell Line, Tumor , Cell Proliferation/drug effectsABSTRACT
ABSTRACT: Acute lymphoblastic leukemia (ALL) arises from the uncontrolled proliferation of B-cell precursors (BCP-ALL) or T cells (T-ALL). Current treatment protocols obtain high cure rates in children but are based on toxic polychemotherapy. Novel therapies are urgently needed, especially in relapsed/refractory (R/R) disease, high-risk (HR) leukemias and T-ALL, in which immunotherapy approaches remain scarce. Although the interleukin-7 receptor (IL-7R) plays a pivotal role in ALL development, no IL-7R-targeting immunotherapy has yet reached clinical application in ALL. The IL-7Rα chain (CD127)-targeting IgG4 antibody lusvertikimab (LUSV; formerly OSE-127) is a full antagonist of the IL-7R pathway, showing a good safety profile in healthy volunteers. Here, we show that â¼85% of ALL cases express surface CD127. We demonstrate significant in vivo efficacy of LUSV immunotherapy in a heterogeneous cohort of BCP- and T-ALL patient-derived xenografts (PDX) in minimal residual disease (MRD) and overt leukemia models, including R/R and HR leukemias. Importantly, LUSV was particularly effective when combined with polychemotherapy in a phase 2-like PDX study with CD127high samples leading to MRD-negativity in >50% of mice treated with combination therapy. Mechanistically, LUSV targeted ALL cells via a dual mode of action comprising direct IL-7R antagonistic activity and induction of macrophage-mediated antibody-dependent cellular phagocytosis (ADCP). LUSV-mediated in vitro ADCP levels significantly correlated with CD127 expression levels and the reduction of leukemia burden upon treatment of PDX animals in vivo. Altogether, through its dual mode of action and good safety profile, LUSV may represent a novel immunotherapy option for any CD127+ ALL, particularly in combination with standard-of-care polychemotherapy.
Subject(s)
Xenograft Model Antitumor Assays , Animals , Humans , Mice , Receptors, Interleukin-7/antagonists & inhibitors , Mice, SCID , Phagocytosis/drug effects , Interleukin-7 Receptor alpha Subunit , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Precursor Cell Lymphoblastic Leukemia-Lymphoma/immunology , Female , Mice, Inbred NOD , Antibodies, Monoclonal, Humanized/therapeutic use , Antibodies, Monoclonal, Humanized/pharmacology , Cell Line, Tumor , Antineoplastic Agents, Immunological/pharmacology , Antineoplastic Agents, Immunological/therapeutic useABSTRACT
CD19-directed immunotherapy has become a cornerstone in the therapy of B-cell precursor acute lymphoblastic leukemia (BCP-ALL). CD19-directed cellular and antibody-based therapeutics have entered therapy of primary and relapsed disease and contributed to improved outcomes in relapsed disease and lower therapy toxicity. However, efficacy remains limited in many cases due to a lack of therapy response, short remission phases, or antigen escape. Here, BCP-ALL cell lines, patient-derived xenograft (PDX) samples, human macrophages, and an in vivo transplantation model in NOD.Cg-PrkdcscidIl2rgtm1Wjl/SzJ (NSG) mice were used to examine the therapeutic potency of a CD19 antibody Fc-engineered for improved effector cell recruitment (CD19-DE) and antibody-dependent cellular phagocytosis (ADCP), in combination with a novel modified CD47 antibody (Hu5F9-IgG2σ). For the in vivo model, only samples refractory to CD19-DE monotherapy were chosen. Hu5F9-IgG2σ enhanced ADCP by CD19-DE in various BCP-ALL cell line models with varying CD19 surface expression and cytogenetic backgrounds, two of which contained the KMT2A-AFF1 fusion. Also, the antibody combination was efficient in inducing ADCP by human macrophages in pediatric PDX samples with and adult samples with and without KMT2A-rearrangement in vitro. In a randomized phase 2-like PDX trial using seven KMT2A-rearranged BCP-ALL samples in NSG mice, the CD19/CD47 antibody combination proved highly efficient. Our findings support that the efficacy of Fc-engineered CD19 antibodies may be substantially enhanced by a combination with CD47 blockade. This suggests that the combination may be a promising therapy option for BCP-ALL, especially in relapsed patients and/or patients refractory to CD19-directed therapy.
ABSTRACT
Acute myeloid leukemia (AML) is characterized by complex molecular alterations and driver mutations. Elderly patients show increased frequencies of IDH mutations with high chemoresistance and relapse rates despite recent therapeutic advances. Besides being associated with global promoter hypermethylation, IDH1 mutation facilitated changes in 3D DNA-conformation by CTCF-anchor methylation and upregulated oncogene expression in glioma, correlating with poor prognosis. Here, we investigated the role of IDH1 p.R132H mutation in altering 3D DNA-architecture and subsequent oncogene activation in AML. Using public RNA-Seq data, we identified upregulation of tyrosine kinase PDGFRA in IDH1-mutant patients, correlating with poor prognosis. DNA methylation analysis identified CpG hypermethylation within a CTCF-anchor upstream of PDGFRA in IDH1-mutant patients. Increased PDGFRA expression, PDGFRA-CTCF methylation and decreased CTCF binding were confirmed in AML CRISPR cells with heterozygous IDH1 p.R132H mutation and upon exogenous 2-HG treatment. IDH1-mutant cells showed higher sensitivity to tyrosine kinase inhibitor dasatinib, which was supported by reduced blast count in a patient with refractory IDH1-mutant AML after dasatinib treatment. Our data illustrate that IDH1 p.R132H mutation leads to CTCF hypermethylation, disrupting DNA-looping and insulation of PDGFRA, resulting in PDGFRA upregulation in IDH1-mutant AML. Treatment with dasatinib may offer a novel treatment strategy for IDH1-mutant AML.
Subject(s)
Isocitrate Dehydrogenase , Leukemia, Myeloid, Acute , Humans , Aged , Isocitrate Dehydrogenase/genetics , Isocitrate Dehydrogenase/metabolism , Dasatinib , Mutation , Oncogenes , Leukemia, Myeloid, Acute/genetics , Carcinogenesis/geneticsABSTRACT
Immunotherapy has evolved as a powerful tool for the treatment of B-cell malignancies, and patient outcomes have improved by combining therapeutic antibodies with conventional chemotherapy. Overexpression of antiapoptotic B-cell lymphoma 2 (Bcl-2) is associated with a poor prognosis, and increased levels have been described in patients with "double-hit" diffuse large B-cell lymphoma, a subgroup of Burkitt's lymphoma, and patients with pediatric acute lymphoblastic leukemia harboring a t(17;19) translocation. Here, we show that the addition of venetoclax (VEN), a specific Bcl-2 inhibitor, potently enhanced the efficacy of the therapeutic anti-CD20 antibody rituximab, anti-CD38 daratumumab, and anti-CD19-DE, a proprietary version of tafasitamab. This was because of an increase in antibody-dependent cellular phagocytosis by macrophages as shown in vitro and in vivo in cell lines and patient-derived xenograft models. Mechanistically, double-hit lymphoma cells subjected to VEN triggered phagocytosis in an apoptosis-independent manner. Our study identifies the combination of VEN and therapeutic antibodies as a promising novel strategy for the treatment of B-cell malignancies.
Subject(s)
Cytophagocytosis , Lymphoma, Large B-Cell, Diffuse , Bridged Bicyclo Compounds, Heterocyclic/pharmacology , Bridged Bicyclo Compounds, Heterocyclic/therapeutic use , Child , Humans , Lymphoma, Large B-Cell, Diffuse/drug therapy , Proto-Oncogene Proteins c-bcl-2 , SulfonamidesABSTRACT
Acute lymphoblastic leukemia (ALL) is the most common malignant disease affecting children. Although therapeutic strategies have improved, T-cell acute lymphoblastic leukemia (T-ALL) relapse is associated with chemoresistance and a poor prognosis. One strategy to overcome this obstacle is the application of monoclonal antibodies. Here, we show that leukemic cells from patients with T-ALL express surface CD38 and CD47, both attractive targets for antibody therapy. We therefore investigated the commercially available CD38 antibody daratumumab (Dara) in combination with a proprietary modified CD47 antibody (Hu5F9-IgG2σ) in vitro and in vivo. Compared with single treatments, this combination significantly increased in vitro antibody-dependent cellular phagocytosis in T-ALL cell lines as well as in random de novo and relapsed/refractory T-ALL patient-derived xenograft (PDX) samples. Similarly, enhanced antibody-dependent cellular phagocytosis was observed when combining Dara with pharmacologic inhibition of CD47 interactions using a glutaminyl cyclase inhibitor. Phase 2-like preclinical in vivo trials using T-ALL PDX samples in experimental minimal residual disease-like (MRD-like) and overt leukemia models revealed a high antileukemic efficacy of CD47 blockade alone. However, T-ALL xenograft mice subjected to chemotherapy first (postchemotherapy MRD) and subsequently cotreated with Dara and Hu5F9-IgG2σ displayed significantly reduced bone marrow infiltration compared with single treatments. In relapsed and highly refractory T-ALL PDX combined treatment with Dara and Hu5F9-IgG2σ was required to substantially prolong survival compared with single treatments. These findings suggest that combining CD47 blockade with Dara is a promising therapy for T-ALL, especially for relapsed/refractory disease harboring a dismal prognosis in patients.
Subject(s)
Precursor Cell Lymphoblastic Leukemia-Lymphoma , Precursor T-Cell Lymphoblastic Leukemia-Lymphoma , Animals , Antibodies, Monoclonal/pharmacology , Antibodies, Monoclonal/therapeutic use , CD47 Antigen , Humans , Mice , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/drug therapyABSTRACT
High-throughput sequencing describes multiple alterations in individual tumors, but their functional relevance is often unclear. Clinic-close, individualized molecular model systems are required for functional validation and to identify therapeutic targets of high significance for each patient. Here, we establish a Cre-ERT2-loxP (causes recombination, estrogen receptor mutant T2, locus of X-over P1) based inducible RNAi- (ribonucleic acid interference) mediated gene silencing system in patient-derived xenograft (PDX) models of acute leukemias in vivo. Mimicking anti-cancer therapy in patients, gene inhibition is initiated in mice harboring orthotopic tumors. In fluorochrome guided, competitive in vivo trials, silencing of the apoptosis regulator MCL1 (myeloid cell leukemia sequence 1) correlates to pharmacological MCL1 inhibition in patients´ tumors, demonstrating the ability of the method to detect therapeutic vulnerabilities. The technique identifies a major tumor-maintaining potency of the MLL-AF4 (mixed lineage leukemia, ALL1-fused gene from chromosome 4) fusion, restricted to samples carrying the translocation. DUX4 (double homeobox 4) plays an essential role in patients' leukemias carrying the recently described DUX4-IGH (immunoglobulin heavy chain) translocation, while the downstream mediator DDIT4L (DNA-damage-inducible transcript 4 like) is identified as therapeutic vulnerability. By individualizing functional genomics in established tumors in vivo, our technique decisively complements the value chain of precision oncology. Being broadly applicable to tumors of all kinds, it will considerably reinforce personalizing anti-cancer treatment in the future.
Subject(s)
Antineoplastic Agents/pharmacology , Biomarkers, Tumor/genetics , Leukemia, Myeloid, Acute/drug therapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Reverse Genetics/methods , Adaptor Proteins, Signal Transducing/antagonists & inhibitors , Adaptor Proteins, Signal Transducing/genetics , Adult , Animals , Antineoplastic Agents/therapeutic use , Biomarkers, Tumor/antagonists & inhibitors , Child , Female , Gene Silencing , Homeodomain Proteins/antagonists & inhibitors , Homeodomain Proteins/genetics , Humans , Leukemia, Myeloid, Acute/genetics , Male , Mice , Myeloid Cell Leukemia Sequence 1 Protein/antagonists & inhibitors , Myeloid Cell Leukemia Sequence 1 Protein/genetics , Myeloid-Lymphoid Leukemia Protein/antagonists & inhibitors , Myeloid-Lymphoid Leukemia Protein/genetics , Oncogene Proteins, Fusion/antagonists & inhibitors , Oncogene Proteins, Fusion/genetics , Precision Medicine/methods , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Xenograft Model Antitumor AssaysABSTRACT
B-cell precursor acute lymphoblastic leukemia (BCP-ALL) is the most frequent malignancy in children and also occurs in adulthood. Despite high cure rates, BCP-ALL chemotherapy can be highly toxic. This type of toxicity can most likely be reduced by antibody-based immunotherapy targeting the CD19 antigen which is commonly expressed on BCP-ALL cells. In this study, we generated a novel Fc-engineered CD19-targeting IgG1 antibody fused to a single chain tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) domain (CD19-TRAIL). As TRAIL induces apoptosis in tumor cells but not in healthy cells, we hypothesized that CD19-TRAIL would show efficient killing of BCP-ALL cells. CD19-TRAIL showed selective binding capacity and pronounced apoptosis induction in CD19-positive (CD19+) BCP-ALL cell lines in vitro and in vivo. Additionally, CD19-TRAIL significantly prolonged survival of mice transplanted with BCP-ALL patient-derived xenograft (PDX) cells of different cytogenetic backgrounds. Moreover, simultaneous treatment with CD19-TRAIL and Venetoclax (VTX), an inhibitor of the anti-apoptotic protein BCL-2, promoted synergistic apoptosis induction in CD19+ BCP-ALL cells in vitro and prolonged survival of NSG-mice bearing the BCP-ALL cell line REH. Therefore, IgG1-based CD19-TRAIL fusion proteins represent a new potential immunotherapeutic agent against BCP-ALL.
ABSTRACT
BACKGROUND & AIMS: A large unmet therapeutic need exists in inflammatory bowel disease (IBD). Inhibition of interleukin (IL)-6 appears to be effective, but the therapeutic benefit of a complete IL6/IL6 receptor (IL6R) blockade is limited by profound immunosuppression. Evidence has emerged that chronic proinflammatory activity of IL6 is mainly mediated by trans-signaling via a complex of IL6 bound to soluble IL6R engaging the gp130 co-receptor without the need for membrane-bound IL6R. We have developed a decoy protein, sgp130Fc, that exclusively blocks IL6 proinflammatory trans-signaling and has shown efficacy in preclinical models of IBD, without signs of immunosuppression. METHODS: We present a 12-week, open-label, prospective phase 2a trial (FUTURE) in 16 patients with active IBD treated with the trans-signaling inhibitor olamkicept (sgp130Fc) to assess the molecular mechanisms, safety, and effectiveness of IL6 trans-signaling blockade in vivo. We performed in-depth molecular profiling at various timepoints before and after therapy induction to identify the mechanism of action of olamkicept. RESULTS: Olamkicept was well tolerated and induced clinical response in 44% and clinical remission in 19% of patients. Clinical effectiveness coincided with target inhibition (reduction of phosphorylated STAT3) and marked transcriptional changes in the inflamed mucosa. An olamkicept-specific transcriptional signature, distinguishable from remission signatures of anti-tumor necrosis factor (infliximab) or anti-integrin (vedolizumab) therapies was identified. CONCLUSIONS: Our data suggest that blockade of IL6 trans-signaling holds great promise for the therapy of IBD and should undergo full clinical development as a new immunoregulatory therapy for IBD. (EudraCT no., Nu 2016-000205-36).
Subject(s)
Colitis, Ulcerative/drug therapy , Crohn Disease/drug therapy , Interleukin-6/antagonists & inhibitors , Recombinant Fusion Proteins/pharmacology , Signal Transduction/drug effects , Adult , Aged , Colitis, Ulcerative/immunology , Crohn Disease/immunology , Female , Humans , Male , Middle Aged , Prospective Studies , Receptors, Interleukin-6/metabolism , Severity of Illness Index , Treatment Outcome , Young AdultABSTRACT
Central nervous system (CNS) involvement remains a challenge in the diagnosis and treatment of acute lymphoblastic leukemia (ALL). In this study, we identify CD79a (also known as Igα), a signaling component of the preB cell receptor (preBCR), to be associated with CNS-infiltration and -relapse in B-cell precursor (BCP)-ALL patients. Furthermore, we show that downregulation of CD79a hampers the engraftment of leukemia cells in different murine xenograft models, particularly in the CNS.
Subject(s)
CD79 Antigens/metabolism , Central Nervous System Neoplasms/metabolism , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/metabolism , src-Family Kinases/metabolism , Animals , Cell Line, Tumor , Humans , Mice , Xenograft Model Antitumor AssaysABSTRACT
Ph+ acute lymphoblastic leukemia (ALL) is characterized by the expression of an oncogenic fusion kinase termed BCR-ABL1. Here, we show that interleukin 7 receptor (IL7R) interacts with the chemokine receptor CXCR4 to recruit BCR-ABL1 and JAK kinases in close proximity. Treatment with BCR-ABL1 kinase inhibitors results in elevated expression of IL7R which enables the survival of transformed cells when IL7 was added together with the kinase inhibitors. Importantly, treatment with anti-IL7R antibodies prevents leukemia development in xenotransplantation models using patient-derived Ph+ ALL cells. Our results suggest that the association between IL7R and CXCR4 serves as molecular platform for BCR-ABL1-induced transformation and development of Ph+ ALL. Targeting this platform with anti-IL7R antibody eliminates Ph+ ALL cells including those with resistance to commonly used ABL1 kinase inhibitors. Thus, anti-IL7R antibodies may provide alternative treatment options for ALL in general and may suppress incurable drug-resistant leukemia forms.
Subject(s)
Fusion Proteins, bcr-abl/metabolism , Interleukin-7 Receptor alpha Subunit/metabolism , Philadelphia Chromosome , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Receptors, CXCR4/metabolism , Animals , Cell Line, Tumor , Cell Transformation, Neoplastic/drug effects , Female , Forkhead Box Protein O1/metabolism , Fusion Proteins, bcr-abl/antagonists & inhibitors , Fusion Proteins, bcr-abl/genetics , Gene Expression Regulation, Neoplastic/drug effects , Humans , Interleukin-7/pharmacology , Interleukin-7 Receptor alpha Subunit/antagonists & inhibitors , Interleukin-7 Receptor alpha Subunit/genetics , Mice , Mice, Mutant Strains , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/metabolism , Protein Kinase Inhibitors/pharmacology , Receptors, CXCR4/genetics , Signal Transduction/drug effectsABSTRACT
Acute lymphoblastic leukemia (ALL) is the most common childhood cancer. One of the major clinical challenges is adequate diagnosis and treatment of central nervous system (CNS) involvement in this disease. Intriguingly, there is little solid evidence on the mechanisms sustaining CNS disease in ALL. Here, we present and discuss recent data on this topic, which are mainly derived from preclinical model systems. We thereby highlight sites and routes of leukemic CNS infiltration, cellular features promoting infiltration and survival of leukemic cells in a presumably hostile niche, and dormancy as a potential mechanism of survival and relapse in CNS leukemia. We also focus on the impact of ALL cytogenetic subtypes on features associated with a particular CNS tropism. Finally, we speculate on new perspectives in the treatment of ALL in the CNS, including ideas on the impact of novel immunotherapies.
Subject(s)
Central Nervous System/pathology , Leukemic Infiltration/pathology , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Child , HumansSubject(s)
Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/genetics , Protein Kinase Inhibitors/therapeutic use , Proteins/antagonists & inhibitors , Proteins/genetics , Pyrazoles/therapeutic use , Pyrimidines/therapeutic use , Animals , Combined Modality Therapy , Disease Models, Animal , Hematopoietic Stem Cell Transplantation , Humans , Mice , Molecular Targeted Therapy , Oncogene Proteins, Fusion/antagonists & inhibitors , Oncogene Proteins, Fusion/genetics , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/pathology , Protein Kinase Inhibitors/pharmacology , Pyrazoles/pharmacology , Pyrimidines/pharmacology , Recurrence , Retreatment , Treatment Outcome , Xenograft Model Antitumor AssaysABSTRACT
Most patients with pancreatic ductal adenocarcinoma (PDAC) undergoing curative resection relapse within months, often with liver metastases. The hepatic microenvironment determines induction and reversal of dormancy during metastasis. Both tumor growth and metastasis depend on the Tumor necrosis factor (TNF)-related apoptosis-inducing ligand-receptor 2 (TRAIL-R2). This study investigated the interplay of TRAIL-R2 and the hepatic microenvironment in liver metastases formation and the impact of surgical resection. Although TRAIL-R2-knockdown (PancTu-I shTR2) decreased local relapses and number of macroscopic liver metastases after primary tumor resection in an orthotopic PDAC model, the number of micrometastases was increased. Moreover, abdominal surgery induced liver inflammation involving activation of hepatic stellate cells (HSCs) into hepatic myofibroblasts (HMFs). In coculture with HSCs, proliferation of PancTu-I shTR2 cells was significantly lower compared to PancTu-I shCtrl cells, an effect still observed after switching coculture from HSC to HMF, mimicking surgery-mediated liver inflammation and enhancing cell proliferation. CXCL-8/IL-8 blockade diminished HSC-mediated growth inhibition in PancTu-I shTR2 cells, while Vascular Endothelial Growth Factor (VEGF) neutralization decreased HMF-mediated proliferation. Overall, this study points to an important role of TRAIL-R2 in PDAC cells in the interplay with the hepatic microenvironment during metastasis. Resection of primary PDAC seems to induce liver inflammation, which might contribute to outgrowth of liver metastases.