scholarly journals Understanding the Evolutionary Games in NSCLC Microenvironment

2020 ◽  
Author(s):  
Ranjini Bhattacharya ◽  
Robert Vander Velde ◽  
Viktoriya Marusyk ◽  
Bina Desai ◽  
Artem Kaznatcheev ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Targeted Therapies ◽  
Evolutionary Dynamics ◽  
Fusion Gene ◽  
Evolutionary Game ◽  
Therapy Resistance ◽  
Resistance Mechanisms ◽  
Intrinsic Resistance ◽  
Frequency Changes

AbstractWhile initially highly successful, targeted therapies eventually fail as populations of tumor cells evolve mechanisms of resistance, leading to resumption of tumor growth. Historically, cell-intrinsic mutational changes have been the major focus of experimental and clinical studies to decipher origins of therapy resistance. While the importance of these mutational changes is undeniable, a growing body of evidence suggests that non-cell autonomous interactions between sub-populations of tumor cells, as well as with non-tumor cells within tumor microenvironment, might have a profound impact on both short term sensitivity of cancer cells to therapies, as well as on the evolutionary dynamics of emergent resistance. In contrast to well established tools to interrogate the functional impact of cell-intrinsic mutational changes, methodologies to understand non-cell autonomous interactions are largely lacking.Evolutionary Game Theory (EGT) is one of the main frameworks to understand the dynamics that drive frequency changes in interacting competing populations with different phenotypic strategies. However, despite a few notable exceptions, the use of EGT to understand evolutionary dynamics in the context of evolving tumors has been largely confined to theoretical studies. In order to apply EGT towards advancing our understanding of evolving tumor populations, we decided to focus on the context of the emergence of resistance to targeted therapies, directed against EML4-ALK fusion gene in lung cancers, as clinical responses to ALK inhibitors represent a poster child of limitations, posed by evolving resistance. To this end, we have examined competitive dynamics between differentially labelled therapy-naïve tumor cells, cells with cell-intrinsic resistance mechanisms, and cells with cell-extrinsic resistance, mediated by paracrine action of hepatocyte growth factor (HGF), within in vitro game assays in the presence or absence of front-line ALK inhibitor alectinib. We found that producers of HGF were the fittest in every pairwise game, while also supporting the proliferation of therapy-naïve cells. Both selective advantage of these producer cells and their impact on total population growth was a linearly increasing function of the initial frequency of producers until eventually reaching a plateau. Resistant cells did not significantly interact with the other two phenotypes. These results provide insights on reconciling selection driven emergence of subpopulations with cell non-cell autonomous resistance mechanisms, with lack of evidence of clonal dominance of these subpopulations. Further, our studies elucidate mechanisms for co-existence of multiple resistance strategies within evolving tumors. This manuscript serves as a technical report and will be followed up with a research paper in a different journal.

scholarly journals NF-κB Dependent Chemokine Signaling in Pancreatic Cancer

Cancers ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 1445 ◽  
Author(s):  
Geismann ◽  
Schäfer ◽  
Gundlach ◽  
Hauser ◽  
Egberts ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Tumor Cell ◽  
Tumor Cells ◽  
Target Genes ◽  
Therapy Resistance ◽  
Resistance Mechanisms ◽  
Ductal Adenocarcinoma ◽  
Therapeutic Resistance ◽  
Intrinsic Resistance ◽  
Chemokine Signaling

Pancreatic cancer is one of the carcinomas with the worst prognoses, as shown by its five-year survival rate of 9%. Although there have been new therapeutic innovations, the effectiveness of these therapies is still limited, resulting in pancreatic ductal adenocarcinoma (PDAC) becoming the second leading cause of cancer-related death in 2020 in the US. In addition to tumor cell intrinsic resistance mechanisms, this disease exhibits a complex stroma consisting of fibroblasts, immune cells, neuronal and vascular cells, along with extracellular matrix, all conferring therapeutic resistance by several mechanisms. The NF-κB pathway is involved in both the tumor cell-intrinsic and microenvironment-mediated therapeutic resistance by regulating the transcription of a plethora of target genes. These genes are involved in nearly all scenarios described as the hallmarks of cancer. In addition to classical regulators of apoptosis, NF-κB regulates the expression of chemokines and their receptors, both in the tumor cells and in cells of the microenvironment. These chemokines mediate autocrine and paracrine loops among tumor cells but also cross-signaling between tumor cells and the stroma. In this review, we will focus on NF-κB-mediated chemokine signaling, with an emphasis on therapy resistance in pancreatic cancer.

γ-Globin, a Tumor-Associated Antigen for Juvenile Myelomonocytic Leukemia (JMML): A Cell-Based Approach To Identify Tumor Antigenic Epitopes That Are Naturally Processed and Presented.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3418-3418
Author(s):  
Naoto Hirano ◽  
Marcus O. Butler ◽  
Zhinan Xia ◽  
Seiji Kojima ◽  
Lee M. Nadler
Keyword(s):  
Mass Spectrometry ◽  
Tumor Cells ◽  
Fusion Gene ◽  
Peptide Sequencing ◽  
Juvenile Myelomonocytic Leukemia ◽  
Peptide Epitope ◽  
Peptide Epitopes ◽  
Tumor Associated Antigen ◽  
Myelomonocytic Leukemia

Abstract Juvenile myelomonocytic leukemia (JMML) is a rare clonal myeloproliferative disorder of early childhood. Although allogeneic stem cell transplantation can induce long-term remissions, relapse rates remain high, and innovative approaches are needed. Since donor lymphocyte infusion in JMML is efficacious, T cell mediated immunotherapy may be effective, and appropriate antigenic targets must be identified. One candidate tumor-associated antigen for the immunotherapy of JMML is γ-globin, which is expressed at high levels in most JMML patients. Most clonogenic JMML cells constitutively express this onco-fetal protein, which is not necessary for the normal erythropoesis of children and adults. To determine whether γ-globin can serve as a target for immunotherapy in JMML, we sought to determine whether γ-globin is naturally processed and presented by the HLA complex. Using conventional bioinformatic techniques and the T2 binding assay to predict candidate epitopes, we identified 4 γ-globin derived peptides (g031, g071, g105, and g106) that were predicted to bind to the HLA-A2 molecule in vitro. Since this strategy provides no evidence for which predicted epitopes are processed and presented by tumor cells in vivo, we employed a biochemical strategy to determine which peptides are naturally processed and presented. This step is critical in certifying that a candidate peptide epitope is an appropriate target for immunotherapy treatments. Using our K562-derived artificial APC (aAPC), an APC that expresses A2 and no other HLA allele, we introduced the EGFP-γ-globin fusion gene. We then acid stripped peptides directly from the surface of one billion aAPC/EGFP-γ-globin cells without subjecting the cells to detergent mediated lysis. Peptides less than 5 kDa in size were fractionated by reverse phased HPLC analysis and analyzed by mass spectrometry. We identified two mass spectrometry peaks which corresponded to γ-globin derived peptides, g031 and g105. Of these, the identity of one peak, g105, was successfully confirmed by peptide sequencing, providing strong evidence that g105 is naturally processed and presented by aAPC/EGFP-γ-globin cells. Next, to confirm that g105 is processed and presented by primary JMML cells, we generated γ-globin specific CD8+ cytotoxic T cells (CTL) from A2 positive healthy donors using synthetic g105 peptide. γ-Globin specific CTL were able to specifically cytolyze A2+ γ-globin+ JMML cells but not A2+ γ-globin- JMML cells. Specific cytotoxicity was blocked by anti-A2 mAb but not isotype control. These results show for the first time that the γ-globin derived peptide, g105, can serve as a target epitope for the CTL directed immunotherapy of JMML. Furthermore, these results illustrate an innovative aAPC based strategy that can identify the antigenic peptide epitopes of putative tumor associated antigens that are naturally processed by tumor cells, presented via HLA class I, and can serve as targets for effective anti-cancer immunotherapy.

scholarly journals An Optimized 3D Coculture Assay for Preclinical Testing of Pro- and Antiangiogenic Drugs

2017 ◽  
Vol 22 (5) ◽  
pp. 602-613 ◽  
Author(s):  
Daniela Unterleuthner ◽  
Nina Kramer ◽  
Karoline Pudelko ◽  
Alexandra Burian ◽  
Markus Hengstschläger ◽  
...  
Keyword(s):  
Basal Membrane ◽  
Cell Interaction ◽  
Resistance Mechanisms ◽  
Culture Conditions ◽  
Angiogenic Factors ◽  
Branch Points ◽  
Intrinsic Resistance ◽  
Antiangiogenic Drugs

Angiogenesis is a promising target for anticancer therapies, but also for treating other diseases with pathologic vessel development. Targeting the vascular endothelial growth factor (VEGF) pathway did not proof as effective as expected due to emerging intrinsic resistance mechanisms, as well as stromal contributions leading to drug insensitivity. Therefore, alternative strategies affecting the interaction of endothelial cells (ECs) with other stromal cells seem to be more promising. Human preclinical in vitro angiogenesis models successfully recapitulating these interactions are rare, and two-dimensional (2D) cell cultures cannot mimic tissue architecture in vivo. Consequently, models combining three-dimensionality with heterotypic cell interaction seem to be better suited. Here, we report on an improved human fibroblast–EC coculture assay mimicking sprouting angiogenesis from EC-covered microbeads resembling existing endothelial structures. Culture conditions were optimized to assess pro- and antiangiogenic compounds. Important characteristics of angiogenesis, that is, the number of sprouts and branch points, sprout length protrusion, and overall vessel structure areas, were quantified. Notably, the endothelial sprouts display lumen formation and basal membrane establishment. In this model, angiogenesis can be inhibited by genetic interference of pro-angiogenic factors expressed in the fibroblasts. Moreover, bona fide antiangiogenic drugs decreased, whereas pro-angiogenic factors increased vessel formation in 24-well and 96-well settings, demonstrating the applicability for screening approaches.

scholarly journals Approaches to identifying drug resistance mechanisms to clinically relevant treatments in childhood rhabdomyosarcoma

2022 ◽  
Author(s):  
Samson Ghilu ◽  
Christopher L. Morton ◽  
Angelina V. Vaseva ◽  
Siyuan Zheng ◽  
Raushan T. Kurmasheva ◽  
...  
Keyword(s):  
Drug Resistance ◽  
High Risk ◽  
Tumor Regression ◽  
Population Level ◽  
Therapy Resistance ◽  
Resistance Mechanisms ◽  
Tumor Resistance ◽  
Intrinsic Resistance ◽  
Clinical Resistance

Aim: Despite aggressive multiagent protocols, patients with metastatic rhabdomyosarcoma (RMS) have poor prognosis. In a recent high-risk trial (ARST0431), 25% of patients failed within the first year, while on therapy and 80% had tumor progression within 24 months. However, the mechanisms for tumor resistance are essentially unknown. Here we explore the use of preclinical models to develop resistance to complex chemotherapy regimens used in ARST0431. Methods: A Single Mouse Testing (SMT) protocol was used to evaluate the sensitivity of 34 RMS xenograft models to one cycle of vincristine, actinomycin D, cyclophosphamide (VAC) treatment. Tumor response was determined by caliper measurement, and tumor regression and event-free survival (EFS) were used as endpoints for evaluation. Treated tumors at regrowth were transplanted into recipient mice, and the treatment was repeated until tumors progressed during the treatment period (i.e., became resistant). At transplant, tumor tissue was stored for biochemical and omics analysis. Results: The sensitivity to VAC of 34 RMS models was determined. EFS varied from 3 weeks to > 20 weeks. Tumor models were classified as having intrinsic resistance, intermediate sensitivity, or high sensitivity to VAC therapy. Resistance to VAC was developed in multiple models after 2-5 cycles of therapy; however, there were examples where sensitivity remained unchanged after 3 cycles of treatment. Conclusion: The SMT approach allows for in vivo assessment of drug sensitivity and development of drug resistance in a large number of RMS models. As such, it provides a platform for assessing in vivo drug resistance mechanisms at a “population” level, simulating conditions in vivo that lead to clinical resistance. These VAC-resistant models represent “high-risk” tumors that mimic a preclinical phase 2 population and will be valuable for identifying novel agents active against VAC-resistant disease.

scholarly journals Brain microenvironment-driven resistance to immune and targeted therapies in acral melanoma

ESMO Open ◽  
2020 ◽  
Vol 5 (4) ◽  
pp. e000707
Author(s):  
Rebecca Jane Lee ◽  
Garima Khandelwal ◽  
Franziska Baenke ◽  
Alessio Cannistraci ◽  
Kenneth Macleod ◽  
...  
Keyword(s):  
Targeted Therapies ◽  
Immune Escape ◽  
Checkpoint Inhibitors ◽  
Resistance Mechanisms ◽  
Acral Melanoma ◽  
Combination Treatments ◽  
Whole Exome ◽  
Longitudinal Sampling ◽  
The Brain

BackgroundCombination treatments targeting the MEK-ERK pathway and checkpoint inhibitors have improved overall survival in melanoma. Resistance to treatment especially in the brain remains challenging, and rare disease subtypes such as acral melanoma are not typically included in trials. Here we present analyses from longitudinal sampling of a patient with metastatic acral melanoma that became resistant to successive immune and targeted therapies.MethodsWe performed whole-exome sequencing and RNA sequencing on an acral melanoma that progressed on successive immune (nivolumab) and targeted (dabrafenib) therapy in the brain to identify resistance mechanisms. In addition, we performed growth inhibition assays, reverse phase protein arrays and immunoblotting on patient-derived cell lines using dabrafenib in the presence or absence of cerebrospinal fluid (CSF) in vitro. Patient-derived xenografts were also developed to analyse response to dabrafenib.ResultsImmune escape following checkpoint blockade was not due to loss of tumour cell recognition by the immune system or low neoantigen burden, but was associated with distinct changes in the microenvironment. Similarly, resistance to targeted therapy was not associated with acquired mutations but upregulation of the AKT/phospho-inositide 3-kinase pathway in the presence of CSF.ConclusionHeterogeneous tumour interactions within the brain microenvironment enable progression on immune and targeted therapies and should be targeted in salvage treatments.

scholarly journals A glutaminase isoform switch drives therapeutic resistance and disease progression of prostate cancer

2021 ◽  
Vol 118 (13) ◽  
pp. e2012748118
Author(s):  
Lingfan Xu ◽  
Yu Yin ◽  
Yanjing Li ◽  
Xufeng Chen ◽  
Yan Chang ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Disease Progression ◽  
Tumor Cells ◽  
Therapeutic Effect ◽  
Hormonal Therapy ◽  
Therapy Resistance ◽  
Therapeutic Resistance ◽  
Switch Mechanism

Cellular metabolism in cancer is significantly altered to support the uncontrolled tumor growth. How metabolic alterations contribute to hormonal therapy resistance and disease progression in prostate cancer (PCa) remains poorly understood. Here we report a glutaminase isoform switch mechanism that mediates the initial therapeutic effect but eventual failure of hormonal therapy of PCa. Androgen deprivation therapy inhibits the expression of kidney-type glutaminase (KGA), a splicing isoform of glutaminase 1 (GLS1) up-regulated by androgen receptor (AR), to achieve therapeutic effect by suppressing glutaminolysis. Eventually the tumor cells switch to the expression of glutaminase C (GAC), an androgen-independent GLS1 isoform with more potent enzymatic activity, under the androgen-deprived condition. This switch leads to increased glutamine utilization, hyperproliferation, and aggressive behavior of tumor cells. Pharmacological inhibition or RNA interference of GAC shows better treatment effect for castration-resistant PCa than for hormone-sensitive PCa in vitro and in vivo. In summary, we have identified a metabolic function of AR action in PCa and discovered that the GLS1 isoform switch is one of the key mechanisms in therapeutic resistance and disease progression.

scholarly journals Evaluation of NTRK Gene Fusion by Five Different Platforms in Triple-Negative Breast Carcinoma

2021 ◽  
Vol 8 ◽  
Author(s):  
Shafei Wu ◽  
Xiaohua Shi ◽  
Xinyu Ren ◽  
Kaimi Li ◽  
Junyi Pang ◽  
...  
Keyword(s):  
Breast Carcinoma ◽  
Tumor Cells ◽  
Targeted Therapies ◽  
Gene Fusion ◽  
Triple Negative ◽  
Fusion Gene ◽  
Rare Event ◽  
Nuclear Staining ◽  
Rt Pcr ◽  
Triple Negative Breast Carcinoma

Triple-negative breast carcinoma (TNBC) is an aggressive disease that has a poor prognosis since it lacks effective treatment methods. Neurotrophic tyrosine receptor kinase (NTRK) fusion genes are excellent candidates for targeted RTK inhibitor therapies and there are available targeted therapy drugs for the treatment of TRK fusion-positive tumors in a tumor agnostic pattern. Our study was designed to investigate the NTRK gene fusion status in TNBC patients and to determine whether RTK-targeted therapies are suitable for TNBC patients. A total of 305 TNBC patients were enrolled in our study. IHC was employed as a prescreening method, and IHC positive cases were further submitted for evaluation by FISH, RT-PCR, and NGS methods. NTRK IHC was evaluated successfully in 287 of the 305 cases, and there were 32 (11.15%) positive cases. FISH was carried out in the 32 IHC positive cases. There were 13 FISH-positive cases if the threshold was set as >15% of the 100 counted tumor cells having a split orange and green signal with more than one signal diameter. There were only 2 FISH-positive cases if the cutoff value was defined as >15% of the counted tumor cells having a split signal with more than two signal diameter widths. One of the FISH-positive cases had a separate NTRK3 FISH signal in 88% of the tumor cells, and its IHC result was strong nuclear staining in all the tumor cells. After evaluation of the morphology, it was re-diagnosed as secretory breast carcinoma, and the NGS result confirmed that it had a NTRK3-ETV6 fusion gene. The other FISH-positive cases were all negative for NTRK gene fusion in the NGS or RT-PCR examination. The NTRK gene fusion rate was low in our TNBC cohort. NTRK gene fusion may be a rare event in TNBC. The high false-positive rate of NTRK gene fusion detected by IHC questions its role as a prescreening method in TNBC. More data may be needed to determine a suitable threshold for NTRK FISH in TNBC in the future. More studies are needed to confirm whether RTK-targeted therapies are appropriate treatments for TNBC patients.

scholarly journals MAB_2355c Confers Macrolide Resistance in Mycobacterium abscessus by Ribosome Protection

2021 ◽  
Author(s):  
Qi Guo ◽  
Yongjie Zhang ◽  
Junsheng Fan ◽  
Haonan Zhang ◽  
Zhemin Zhang ◽  
...  
Keyword(s):  
Atp Hydrolysis ◽  
Gene Knockout ◽  
Antibiotic Sensitivity ◽  
Resistance Mechanisms ◽  
Mycobacterium Abscessus ◽  
Macrolide Resistance ◽  
Intrinsic Resistance ◽  
Family Protein ◽  
Increased Sensitivity

Macrolide resistance is always a concern when treating Mycobacterium abscessus infections. MAB_2355c was identified previously as a possible new factor that confers the intrinsic resistance of 194 clinical M. abscessus isolates to clarithromycin. Herein, the potential mechanism by which MAB_2355c exerts macrolide resistance was explored by bioinformatics analysis, MAB_2355 cloning and protein purification, ATP hydrolysis assay, gene knockout and complementation, antibiotic sensitivity, and transcription-translation assays. MAB_2355c is a putative ATP-binding cassette F (ABC-F) family protein. Purified MAB_2355c protein exhibits ATP hydrolysis activity, which can be inhibited by ribosome-targeting antibiotics. MAB_2355c mRNA expression is upregulated more significantly after exposure to macrolides than exposure to other ribosome-targeting antibiotics. MAB_2355c deleted strains showed increased sensitivity to macrolides, which was reduced by MAB_2355c complementation. Finally, MAB_2355c rescued the transcription and translation activities affected by macrolides in vitro . These findings suggest that MAB_2355c confers the resistance of M. abscessus to macrolides by ribosome protection, thus complementing other known resistance mechanisms.

scholarly journals Advances in Chemokine Signaling Pathways as Therapeutic Targets in Glioblastoma

Cancers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2983
Author(s):  
Ruth M. Urbantat ◽  
Peter Vajkoczy ◽  
Susan Brandenburg
Keyword(s):  
Targeted Therapies ◽  
Clinical Studies ◽  
Standard Of Care ◽  
Therapy Resistance ◽  
Resistance Mechanisms ◽  
The Novel ◽  
Therapeutic Approaches ◽  
Antiangiogenic Treatment ◽  
Chemokine Signaling ◽  
Preclinical And Clinical Studies

With a median patient survival of 15 months, glioblastoma (GBM) is still one of the deadliest malign tumors. Despite immense efforts, therapeutic regimens fail to prolong GBM patient overall survival due to various resistance mechanisms. Chemokine signaling as part of the tumor microenvironment plays a key role in gliomagenesis, proliferation, neovascularization, metastasis and tumor progression. In this review, we aimed to investigate novel therapeutic approaches targeting various chemokine axes, including CXCR2/CXCL2/IL-8, CXCR3/CXCL4/CXCL9/CXCL10, CXCR4/CXCR7/CXCL12, CXCR6/CXCL16, CCR2/CCL2, CCR5/CCL5 and CX3CR1/CX3CL1 in preclinical and clinical studies of GBM. We reviewed targeted therapies as single therapies, in combination with the standard of care, with antiangiogenic treatment as well as immunotherapy. We found that there are many antagonist-, antibody-, cell- and vaccine-based therapeutic approaches in preclinical and clinical studies. Furthermore, targeted therapies exerted their highest efficacy in combination with other established therapeutic applications. The novel chemokine-targeting therapies have mainly been examined in preclinical models. However, clinical applications are auspicious. Thus, it is crucial to broadly investigate the recently developed preclinical approaches. Promising preclinical applications should then be investigated in clinical studies to create new therapeutic regimens and to overcome therapy resistance to GBM treatment.

scholarly journals The Tumor Suppressor MTUS1/ATIP1 Modulates Tumor Promotion in Glioma: Association with Epigenetics and DNA Repair

Cancers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1245
Author(s):  
Nikhil Ranjan ◽  
Vimal Pandey ◽  
Manas Kumar Panigrahi ◽  
Lukas Klumpp ◽  
Ulrike Naumann ◽  
...  
Keyword(s):  
High Grade Glioma ◽  
Therapy Resistance ◽  
Resistance Mechanisms ◽  
Tumor Resistance ◽  
Tumor Irradiation ◽  
Damage Repair ◽  
Low Passage ◽  
Novel Therapeutic Strategies

Glioblastoma (GBM) is a highly aggressive brain tumor. Resistance mechanisms in GBM present an array of challenges to understand its biology and to develop novel therapeutic strategies. We investigated the role of a TSG, MTUS1/ATIP1 in glioma. Glioma specimen, cells and low passage GBM sphere cultures (GSC) were analyzed for MTUS1/ATIP1 expression at the RNA and protein level. Methylation analyses were done by bisulfite sequencing (BSS). The consequence of chemotherapy and irradiation on ATIP1 expression and the influence of different cellular ATIP1 levels on survival was examined in vitro and in vivo. MTUS1/ATIP1 was downregulated in high-grade glioma (HGG), GSC and GBM cells and hypermethylation at the ATIP1 promoter region seems to be at least partially responsible for this downregulation. ATIP1 overexpression significantly reduced glioma progression by mitigating cell motility, proliferation and facilitate cell death. In glioma-bearing mice, elevated MTUS1/ATIP1 expression prolonged their survival. Chemotherapy, as well as irradiation, recovered ATIP1 expression both in vitro and in vivo. Surprisingly, ATIP1 overexpression increased irradiation-induced DNA-damage repair, resulting in radio-resistance. Our findings indicate that MTUS1/ATIP1 serves as TSG-regulating gliomagenesis, progression and therapy resistance. In HGG, higher MTUS1/ATIP1 expression might interfere with tumor irradiation therapy.

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