scholarly journals Tumor-Associated Macrophages—Implications for Molecular Oncology and Imaging

Biomedicines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 374
Author(s):  
Melanie A. Kimm ◽  
Christopher Klenk ◽  
Marianna Alunni-Fabbroni ◽  
Sophia Kästle ◽  
Matthias Stechele ◽  
...  
Keyword(s):  
Molecular Imaging ◽  
Tumor Microenvironment ◽  
Solid Tumors ◽  
Membrane Receptors ◽  
Cancer Therapies ◽  
Tumor Associated Macrophages ◽  
Molecular Oncology ◽  
Intracellular Proteins

Tumor-associated macrophages (TAMs) represent the largest group of leukocytes within the tumor microenvironment (TME) of solid tumors and orchestrate the composition of anti- as well as pro-tumorigenic factors. This makes TAMs an excellent target for novel cancer therapies. The plasticity of TAMs resulting in varying membrane receptors and expression of intracellular proteins allow the specific characterization of different subsets of TAMs. Those markers similarly allow tracking of TAMs by different means of molecular imaging. This review aims to provides an overview of the origin of tumor-associated macrophages, their polarization in different subtypes, and how characteristic markers of the subtypes can be used as targets for molecular imaging and theranostic approaches.

Glioblastoma Genetic Drivers Dictate the Function of Tumor-Associated Macrophages/Microglia and Responses to CSF1R Inhibition

2021 ◽  
Author(s):  
Rohit Rao ◽  
Rong Han ◽  
Sean Ogurek ◽  
Chengbin Xue ◽  
Lai Man Wu ◽  
...  
Keyword(s):  
Tumor Microenvironment ◽  
Single Cell ◽  
Tumor Therapy ◽  
Pi3k Signaling ◽  
Tumor Associated Macrophages ◽  
Transcriptomic Profiling ◽  
Angiogenic Therapy ◽  
Specific Tumor ◽  
Glioma Growth

Abstract Background Tumor-associated macrophages/microglia (TAMs) are prominent microenvironment components in human glioblastoma (GBM) that are potential targets for anti-tumor therapy. However, TAM depletion by CSF1R inhibition showed mixed results in clinical trials. We hypothesized that GBM subtype-specific tumor microenvironment convey distinct sensitivities to TAM targeting. Methods We generated syngeneic PDGFB-driven and RAS-driven GBM models that resemble proneural-like and mesenchymal-like gliomas, and determined the effect of TAM targeting by CSF1R inhibitor PLX3397 on glioma growth. We also investigated the co-targeting of TAMs and angiogenesis on PLX3397-resistant RAS-driven GBM. Using single-cell transcriptomic profiling, we further explored differences in tumor microenvironment cellular compositions and functions in PDGFB- and RAS-driven gliomas. Results We found that growth of PDGFB-driven tumors was markedly inhibited by PLX3397. In contrast, depletion of TAMs at the early phase accelerated RAS-driven tumor growth and had no effects on other proneural and mesenchymal GBM models. In addition, PLX3397-resistant RAS-driven tumors did not respond to PI3K signaling inhibition. Single-cell transcriptomic profiling revealed that PDGFB-driven gliomas induced expansion and activation of pro-tumor microglia, whereas TAMs in mesenchymal RAS-driven GBM were enriched in pro-inflammatory and angiogenic signaling. Co-targeting of TAMs and angiogenesis decreased cell proliferation and changed the morphology of RAS-driven gliomas. Conclusions Our work identify functionally distinct TAM subpopulations in the growth of different glioma subtypes. Notably, we uncover a potential responsiveness of resistant mesenchymal-like gliomas to combined anti-angiogenic therapy and CSF1R inhibition. These data highlight the importance of characterization of the microenvironment landscape in order to optimally stratify patients for TAM-targeted therapy.

ROS-responsive nanomedicine: Towards targeting the breast tumor microenvironment

2020 ◽  
Vol 28 ◽  
Author(s):  
RamaRao Malla ◽  
Mohammad Amjad Kamal
Keyword(s):  
Reactive Oxygen Species ◽  
Gene Therapy ◽  
Drug Resistance ◽  
Molecular Imaging ◽  
Tumor Microenvironment ◽  
Immune Cells ◽  
Breast Tumor ◽  
Imaging Techniques ◽  
Oxygen Species ◽  
Massive Accumulation

: The breast tumor microenvironment (TME) promotes drug resistance through an elaborated interaction of TME components mediated by reactive oxygen species (ROS). Despite a massive accumulation of data concerning the targeting the ROS, but little is known about the ROS-responsive nanomedicine for targeting breast TME. This review submits the ROS landscape in breast TME, including ROS biology, ROS mediated carcinogenesis, reprogramming of stromal and immune cells of TME. We also discussed ROS-based precision strategies for imaging TME, including molecular imaging techniques with advanced probes, multiplexed methods, and multi-omic profiling strategies. ROS-responsive nanomedicine also describes various therapies, such as chemo-dynamic, photodynamic, photothermal, sono-dynamic, immune, and gene therapy for BC. We expound ROS-responsive primary delivery systems for chemotherapeutics, phytochemicals, and immunotherapeutics. This review also presents recent updates on nano-theranostics for simultaneous diagnosis and treatment of BCs. We assume that review on this advancing field will be beneficial to the development of ROS-based nanotheranostics for BC.

scholarly journals Recent Advancements on Immunomodulatory Mechanisms of Resveratrol in Tumor Microenvironment

Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1343
Author(s):  
Gagan Chhabra ◽  
Chandra K. Singh ◽  
Deeba Amiri ◽  
Neha Akula ◽  
Nihal Ahmad
Keyword(s):  
Tumor Microenvironment ◽  
Immune Cell ◽  
Cancer Therapies ◽  
Regulatory Cells ◽  
Immunomodulatory Effects ◽  
Cancer Management ◽  
Natural Agents ◽  
Anticancer Effects ◽  
Cancer Types ◽  
Immune Related Genes

Immunomodulation of the tumor microenvironment is emerging as an important area of research for the treatment of cancer patients. Several synthetic and natural agents are being investigated for their ability to enhance the immunogenic responses of immune cells present in the tumor microenvironment to impede tumor cell growth and dissemination. Among them, resveratrol, a stilbenoid found in red grapes and many other natural sources, has been studied extensively. Importantly, resveratrol has been shown to possess activity against various human diseases, including cancer. Mechanistically, resveratrol has been shown to regulate an array of signaling pathways and processes involving oxidative stress, inflammation, apoptosis, and several anticancer effects. Furthermore, recent research suggests that resveratrol can regulate various cellular signaling events including immune cell regulation, cytokines/chemokines secretion, and the expression of several other immune-related genes. In this review, we have summarized recent findings on resveratrol’s effects on immune regulatory cells and associated signaling in various cancer types. Numerous immunomodulatory effects of resveratrol suggest it may be useful in combination with other cancer therapies including immunotherapy for effective cancer management.

scholarly journals Current Trends in Non-Invasive Imaging of Interactions in the Liver Tumor Microenvironment Mediated by Tumor Metabolism

Cancers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 3645
Author(s):  
Isabel Theresa Schobert ◽  
Lynn Jeanette Savic
Keyword(s):  
Tumor Microenvironment ◽  
Liver Cancer ◽  
Cancer Cells ◽  
Imaging Techniques ◽  
Treatment Strategies ◽  
Tumor Metabolism ◽  
Resistance Mechanisms ◽  
Metabolic Reprogramming ◽  
Non Invasive

With the increasing understanding of resistance mechanisms mediated by the metabolic reprogramming in cancer cells, there is a growing clinical interest in imaging technologies that allow for the non-invasive characterization of tumor metabolism and the interactions of cancer cells with the tumor microenvironment (TME) mediated through tumor metabolism. Specifically, tumor glycolysis and subsequent tissue acidosis in the realms of the Warburg effect may promote an immunosuppressive TME, causing a substantial barrier to the clinical efficacy of numerous immuno-oncologic treatments. Thus, imaging the varying individual compositions of the TME may provide a more accurate characterization of the individual tumor. This approach can help to identify the most suitable therapy for each individual patient and design new targeted treatment strategies that disable resistance mechanisms in liver cancer. This review article focuses on non-invasive positron-emission tomography (PET)- and MR-based imaging techniques that aim to visualize the crosstalk between tumor cells and their microenvironment in liver cancer mediated by tumor metabolism.

scholarly journals Tumor-associated macrophages: potential therapeutic strategies and future prospects in cancer

2021 ◽  
Vol 9 (1) ◽  
pp. e001341
Author(s):  
Chunxiao Li ◽  
Xiaofei Xu ◽  
Shuhua Wei ◽  
Ping Jiang ◽  
Lixiang Xue ◽  
...  
Keyword(s):  
Tumor Microenvironment ◽  
Tumor Progression ◽  
Cancer Cells ◽  
Poor Prognosis ◽  
Tumor Immunotherapy ◽  
Therapeutic Strategies ◽  
Preclinical Studies ◽  
Future Prospects ◽  
Tumor Associated Macrophages

Macrophages are the most important phagocytes in vivo. However, the tumor microenvironment can affect the function and polarization of macrophages and form tumor-associated macrophages (TAMs). Usually, the abundance of TAMs in tumors is closely associated with poor prognosis. Preclinical studies have identified important pathways regulating the infiltration and polarization of TAMs during tumor progression. Furthermore, potential therapeutic strategies targeting TAMs in tumors have been studied, including inhibition of macrophage recruitment to tumors, functional repolarization of TAMs toward an antitumor phenotype, and other therapeutic strategies that elicit macrophage-mediated extracellular phagocytosis and intracellular destruction of cancer cells. Therefore, with the increasing impact of tumor immunotherapy, new antitumor strategies to target TAMs are now being discussed.

scholarly journals Embryonic Origin and Subclonal Evolution of Tumor-Associated Macrophages Imply Preventive Care for Cancer

Cells ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 903
Author(s):  
Xiao-Mei Zhang ◽  
De-Gao Chen ◽  
Shengwen Calvin Li ◽  
Bo Zhu ◽  
Zhong-Jun Li
Keyword(s):  
Metabolic Regulation ◽  
Transcriptional Profiling ◽  
Tumor Development ◽  
Metabolic Reprogramming ◽  
Cancer Therapies ◽  
Functional Heterogeneity ◽  
Tumor Associated Macrophages ◽  
Metabolic Remodeling ◽  
And Function ◽  
Mapping Models

Macrophages are widely distributed in tissues and function in homeostasis. During cancer development, tumor-associated macrophages (TAMs) dominatingly support disease progression and resistance to therapy by promoting tumor proliferation, angiogenesis, metastasis, and immunosuppression, thereby making TAMs a target for tumor immunotherapy. Here, we started with evidence that TAMs are highly plastic and heterogeneous in phenotype and function in response to microenvironmental cues. We pointed out that efforts to tear off the heterogeneous “camouflage” in TAMs conduce to target de facto protumoral TAMs efficiently. In particular, several fate-mapping models suggest that most tissue-resident macrophages (TRMs) are generated from embryonic progenitors, and new paradigms uncover the ontogeny of TAMs. First, TAMs from embryonic modeling of TRMs and circulating monocytes have distinct transcriptional profiling and function, suggesting that the ontogeny of TAMs is responsible for the functional heterogeneity of TAMs, in addition to microenvironmental cues. Second, metabolic remodeling helps determine the mechanism of phenotypic and functional characteristics in TAMs, including metabolic bias from macrophages’ ontogeny in macrophages’ functional plasticity under physiological and pathological conditions. Both models aim at dissecting the ontogeny-related metabolic regulation in the phenotypic and functional heterogeneity in TAMs. We argue that gleaning from the single-cell transcriptomics on subclonal TAMs’ origins may help understand the classification of TAMs’ population in subclonal evolution and their distinct roles in tumor development. We envision that TAM-subclone-specific metabolic reprogramming may round-up with future cancer therapies.

scholarly journals Characterization of tumor‐associated macrophages in prostate cancer transgenic mouse models

The Prostate ◽  
2021 ◽  
Author(s):  
Amber E. Groot ◽  
Kayla V. Myers ◽  
Timothy E. G. Krueger ◽  
Ashley L. Kiemen ◽  
Natalia H. Nagy ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Transgenic Mouse ◽  
Mouse Models ◽  
Transgenic Mouse Models ◽  
Tumor Associated Macrophages

scholarly journals Molecular Classification and Tumor Microenvironment Characterization of Gallbladder Cancer by Comprehensive Genomic and Transcriptomic Analysis

Cancers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 733
Author(s):  
Nobutaka Ebata ◽  
Masashi Fujita ◽  
Shota Sasagawa ◽  
Kazuhiro Maejima ◽  
Yuki Okawa ◽  
...  
Keyword(s):  
Tumor Microenvironment ◽  
Gallbladder Cancer ◽  
Epithelial To Mesenchymal Transition ◽  
Molecular Classification ◽  
Mesenchymal Transition ◽  
Elevated Expression ◽  
Fresh Frozen ◽  
Therapeutic Decision Making

Gallbladder cancer (GBC), a rare but lethal disease, is often diagnosed at advanced stages. So far, molecular characterization of GBC is insufficient, and a comprehensive molecular portrait is warranted to uncover new targets and classify GBC. We performed a transcriptome analysis of both coding and non-coding RNAs from 36 GBC fresh-frozen samples. The results were integrated with those of comprehensive mutation profiling based on whole-genome or exome sequencing. The clustering analysis of RNA-seq data facilitated the classification of GBCs into two subclasses, characterized by high or low expression levels of TME (tumor microenvironment) genes. A correlation was observed between gene expression and pathological immunostaining. TME-rich tumors showed significantly poor prognosis and higher recurrence rate than TME-poor tumors. TME-rich tumors showed overexpression of genes involved in epithelial-to-mesenchymal transition (EMT) and inflammation or immune suppression, which was validated by immunostaining. One non-coding RNA, miR125B1, exhibited elevated expression in stroma-rich tumors, and miR125B1 knockout in GBC cell lines decreased its invasion ability and altered the EMT pathway. Mutation profiles revealed TP53 (47%) as the most commonly mutated gene, followed by ELF3 (13%) and ARID1A (11%). Mutations of ARID1A, ERBB3, and the genes related to the TGF-β signaling pathway were enriched in TME-rich tumors. This comprehensive analysis demonstrated that TME, EMT, and TGF-β pathway alterations are the main drivers of GBC and provides a new classification of GBCs that may be useful for therapeutic decision-making.

scholarly journals Copy Number Variation and Rearrangements Assessment in Cancer: Comparison of Droplet Digital PCR with the Current Approaches

2021 ◽  
Vol 22 (9) ◽  
pp. 4732
Author(s):  
Vincenza Ylenia Cusenza ◽  
Alessandra Bisagni ◽  
Monia Rinaldini ◽  
Chiara Cattani ◽  
Raffaele Frazzi
Keyword(s):  
Digital Pcr ◽  
Genetic Alterations ◽  
Droplet Digital Pcr ◽  
Molecular Oncology ◽  
Therapeutic Choice ◽  
Golden Standard ◽  
Number Variation ◽  
Key Aspects

The cytogenetic and molecular assessment of deletions, amplifications and rearrangements are key aspects in the diagnosis and therapy of cancer. Not only the initial evaluation and classification of the disease, but also the follow-up of the tumor rely on these laboratory approaches. The therapeutic choice can be guided by the results of the laboratory testing. Genetic deletions and/or amplifications directly affect the susceptibility or the resistance to specific therapies. In an era of personalized medicine, the correct and reliable molecular characterization of the disease, also during the therapeutic path, acquires a pivotal role. Molecular assays like multiplex ligation-dependent probe amplification and droplet digital PCR represent exceptional tools for a sensitive and reliable detection of genetic alterations and deserve a role in molecular oncology. In this manuscript we provide a technical comparison of these two approaches with the golden standard represented by fluorescence in situ hybridization. We also describe some relevant targets currently evaluated with these techniques in solid and hematologic tumors.

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