scholarly journals BSCI-08. In vivo two-photon characterization of tumor-associated macrophages and microglia (TAM/M) and CX3CR1 during different steps of brain metastasis formation from lung cancer

2021 ◽  
Vol 3 (Supplement_3) ◽  
pp. iii2-iii3
Author(s):  
Wenlong Zhang ◽  
Philipp Karschnia ◽  
Iven-Alex von Mücke-Heim ◽  
Matthias Mulazzani ◽  
Xiolan Zhou ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Brain Metastasis ◽  
Brain Metastases ◽  
Tumor Cells ◽  
Laser Scanning Microscopy ◽  
Metastasis Formation ◽  
Tumor Associated Macrophages ◽  
Two Photon ◽  
Cranial Window

Abstract Background Brain metastases represent a common complication of lung cancer and dramatically limit prognosis in affected patients. The influence of tumor-associated macrophages and microglia (TAM/M) and their receptor CX3CR1 on different steps of brain metastasis formation from lung cancer is poorly characterized, but might be of therapeutic relevance. Methods We established an orthotopic cerebral metastasis model using CX3CR1-proficient (CX3CR1GFP/wt) and -deficient (CX3CR1GFP/GFP) mice with green-fluorescent TAM/M. A cranial window was prepared, and intracarotid injection of red-fluorescent Lewis Lung Carcinoma-cells (tdtLLC) was performed two weeks later. Formation of brain metastases was followed by repetitive two-photon laser scanning microscopy. Results After intracarotid injection, intravascular tumor cells extravasated into the cerebral parenchyma and eventually formed micrometastases (≤50 cells) and mature macrometastases (>50 cells). We observed phagocytosis of extravasated tumor cells by TAM/M during early steps of metastatic growth. Notably, these anti-tumor effects of TAM/M diminished during later steps of metastasis formation and were accompanied by TAM/M accumulation and activation. CX3CR1-deficiency resulted in a lower number of extravasated tumor cells, and only a small number of TAM/M were visualized during early steps of metastasis formation (extravasation, formation of micrometastases) in such mice. In contrast, progression of extravasated tumor cells into micrometastases was more frequently found in CX3CR1-deficient mice. Overall, these mechanisms resulted in a comparable number of mature macrometastases between CX3CR1-deficient and -proficient mice. Conclusion Our findings indicate that unspecific inhibition of CX3CR1 might not be a suitable therapeutic approach to prevent cerebral dissemination of lung cancer cells. Given the close interaction between TAM/M and tumour cells during metastasis formation, other therapeutic approaches targeting TAM/M function warrant evaluation. Such concepts might be evaluated in vivo using the herein established orthotopic mouse model.

scholarly journals In vivo two-photon characterization of tumor-associated macrophages and microglia (TAM/M) and CX3CR1 during different steps of brain metastasis formation from lung cancer

Neoplasia ◽  
2021 ◽  
Vol 23 (11) ◽  
pp. 1089-1100
Author(s):  
Wenlong Zhang ◽  
Philipp Karschnia ◽  
Iven-Alex von Mücke-Heim ◽  
Matthias Mulazzani ◽  
Xiaolan Zhou ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Brain Metastasis ◽  
Metastasis Formation ◽  
Tumor Associated Macrophages ◽  
Two Photon

scholarly journals TAMI-02. ALTERATIONS IN C-X3-C MOTIF CHEMOKINE RECEPTOR 1 (CX3CR1) EXPRESSION INFLUENCE MICROGLIAL AND MACROPHAGE RESPONSE IN DIFFERENT STEPS OF CEREBRAL METASTASIS FORMATION

2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii213-ii213
Author(s):  
Wenlong Zhang ◽  
Iven-Alex von Mücke-Heim ◽  
Matthias Mulazzani ◽  
Philipp Karschnia ◽  
Andreas Straube ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Tumor Microenvironment ◽  
Tumor Cells ◽  
Laser Scanning Microscopy ◽  
Cerebral Metastasis ◽  
Body Volume ◽  
Metastasis Formation ◽  
Cranial Window ◽  
Deficient Mice

Abstract Metastasis to the brain is a frequent complication in lung cancer and is still associated with a dismal prognosis. Current treatment strategies not only target tumor cells but also focus on cells of the tumor microenvironment like tumor associated microglia/macrophages (TAMs). The interactions between tumor cells and TAMs during different steps of cerebral metastasis formation of lung cancer brain metastasis are poorly characterized. Moreover, the role of CX3CR1 in this process remains unclear. We established a syngeneic cerebral metastasis mouse model by combining a chronic cranial window and two-photon laser scanning microscopy (TPLSM), which allows the tracking of single fluorescent metastasizing tumor cells and the tumor microenvironment on a cellular resolution in vivoover time for a period of weeks. Transgenic CX3CR1 proficient and deficient mice (CX3CRGFP/wt and CX3CR1GFP/GFP) were injected with red fluorescent Lewis lung carcinoma cells. During different steps of metastasis formation (extravasation, formation of micro- and macrometastasis) the density and cell body volume of TAMs, their interaction with tumor cells and possible influence on the fate of single metastatic tumor cells were investigated using serial TPLSM. We found that during metastasis formation TAM density was significantly lower in CX3CR1 deficient mice. However, activation as assessed by TAM morphology did not differ in the absence of CX3CR1. Strikingly, CX3CR1 deficiency was associated with a significant increase of tumor cells successfully extravasating the cerebral vasculature. However, subsequent steps (mirco- and macrometastasis formation) were observed less frequent in CX3CR1 deficient mice. In summary, our results highlight a complex role of CX3CR1 for TAMs during cerebral metastasis formation, indicating anti-tumorous properties of CX3CR1 at early steps and possible pro-tumorous effects at later stages (micro- and macrometastasis formation).

Synergy of nanodiamond-doxorubicin conjugates and PD-L1 blockade effectively turns tumor associated macrophages against tumor cells

2021 ◽  
Author(s):  
Huazhen Xu ◽  
Tongfei Li ◽  
Chao Wang ◽  
Yan Ma ◽  
Yan Liu ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Tumor Cell ◽  
Cancer Cells ◽  
Tumor Cells ◽  
Lung Cancer Cells ◽  
Dependent Manner ◽  
Tumor Associated Macrophages ◽  
M1 Type

Abstract Background: Tumor-associated macrophages (TAM) are the most abundant stromal cells in the tumor microenvironment. Turning the TAM against their host tumor cells is an intriguing therapeutic strategy particularly attractive for patients with immunologically “cold” tumors. This concept was mechanistically demonstrated on in vitro human and murine lung cancer cells and their corresponding TAM models through combinatorial use of nanodiamond-doxorubicin conjugates (Nano-DOX) and a PD-L1 blocking agent BMS-1. Nano-DOX are an agent previously proved to be able to stimulate tumor cells’ immunogenicity and thereby reactivate the TAM into the anti-tumor M1 phenotype. Results: Nano-DOX were first shown to stimulate the tumor cells and the TAM to release the cytokine HMGB1 which, regardless of its source, acted through the RAGE/NF-κB pathway to induce PD-L1 in the tumor cells and PD-L1/PD-1 in the TAM. Interestingly, Nano-DOX also induced NF-κB-dependent RAGE expression in the tumor cells and thus reinforced HMGB1’s action thereon. Then, BMS-1 was shown to enhance Nano-DOX-stimulated M1-type activation of TAM both by blocking Nano-DOX-induced PD-L1 in the TAM and by blocking tumor cell PD-L1 ligation with TAM PD-1. The TAM with enhanced M1-type repolarization both killed the tumor cells and suppressed their growth. BMS-1 could also potentiate Nano-DOX’s action to suppress tumor cell growth via blocking of Nano-DOX-induced PD-L1 therein. Finally, Nano-DOX and BMS-1 achieved synergistic therapeutic efficacy against in vivo tumor grafts in a TAM-dependent manner. Conclusions: PD-L1/PD-1 upregulation mediated by autocrine and paracrine activation of the HMGB1/RAGE/NF-κB signaling is a key response of lung cancer cells and their TAM to stress, which can be induced by Nano-DOX. Blockade of Nano-DOX-induced PD-L1, both in the cancer cells and the TAM, achieves enhanced activation of TAM-mediated anti-tumor response.

TMOD-01. AN IN VIVO FUNCTIONAL GENOMICS SCREEN TO IDENTIFY NOVEL DRIVERS OF LUNG-TO-BRAIN METASTASIS

2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi215-vi215
Author(s):  
Nikoo Aghaei ◽  
Fred C Lam ◽  
Ekkhard Kasper ◽  
Chitra Venugopal ◽  
Sheila K Singh
Keyword(s):  
Lung Cancer ◽  
Brain Metastasis ◽  
Brain Metastases ◽  
Small Cell Lung Cancer ◽  
Cell Lung Cancer ◽  
Small Cell ◽  
Small Cell Lung ◽  
Genome Wide ◽  
Crispr Activation

Abstract INTRODUCTION Brain metastases, the most common tumors of the central nervous system, occur in approximately 20% of primary adult cancers. In particular, 40% of patients with non-small cell lung cancer develop brain metastasis. As systemic therapies for the treatment of non-small cell lung cancer become increasingly effective at controlling primary disease, patients are ironically succumbing to their brain metastases. This highlights a large unmet need to develop novel targeted therapies for the treatment of lung-to-brain metastases (LBM). We hypothesize that an in vivo functional genomic screen can identify novel genes that drive LBM. METHODS To do this, we developed a patient-derived xenograft (PDX) mouse model of LBM using patient lung cancer cell lines. This PDX model of LBM enables the use of fluorescent and bioluminescent in vivo imaging to track the progression of lung tumor and brain metastases. RESULTS We have performed an in vivo genome-wide CRISPR activation screening to identify novel drivers of LBM. We will derive candidate genes through mouse brain and lung tissue sequencing after mice reach endpoint. EXPECTED AREA OF FINDINGS This platform will lead to potential therapeutic targets to prevent the formation of LBM and prolong the survival of patients with non-small cell lung cancer. LIMITATIONS There may be limitations in getting candidate hits that overlap in all mice in our first replicate. This can be remedied by conducting the in vivo screen in at least three biological replicates. CONCLUSION To the best of our knowledge, this is the first genome-wide in vivo CRISPR activation screen searching for drivers of LBM using a PDX animal model. This study can provide a framework to gain a deeper understanding of the regulators of BM formation which will hopefully lead to targeted drug discovery.

scholarly journals BSCI-18. Identifying novel drivers of lung-to-brain metastasis through in vivo functional genomics

2021 ◽  
Vol 3 (Supplement_3) ◽  
pp. iii5-iii5
Author(s):  
Nikoo Aghaei ◽  
Fred C Lam ◽  
Ekkehard Kasper ◽  
Chitra Venugopal ◽  
Sheila Singh
Keyword(s):  
Lung Cancer ◽  
Brain Metastasis ◽  
Brain Metastases ◽  
Small Cell Lung Cancer ◽  
Cell Lung Cancer ◽  
Small Cell ◽  
Small Cell Lung ◽  
Genome Wide ◽  
Crispr Activation

Abstract Introduction Brain metastases, the most common tumors of the central nervous system, occur in approximately 20% of primary adult cancers. In particular, 40% of patients with non-small cell lung cancer develop brain metastasis. As systemic therapies for the treatment of non-small cell lung cancer become increasingly effective at controlling primary disease, patients are ironically succumbing to their brain metastases. This highlights a large unmet need to develop novel targeted therapies for the treatment of lung-to-brain metastases (LBM). We hypothesize that an in vivo functional genomic screen can identify novel genes that drive LBM. Methods To do this, we developed a patient-derived xenograft (PDX) mouse model of LBM using patient lung cancer cell lines. This PDX model of LBM enables the use of fluorescent and bioluminescent in vivo imaging to track the progression of lung tumor and brain metastases. Results We have performed an in vivo genome-wide CRISPR activation screening to identify novel drivers of LBM. We will derive candidate genes through mouse brain and lung tissue sequencing after mice reach endpoint. Expected Area of findings This platform will lead to potential therapeutic targets to prevent the formation of LBM and prolong the survival of patients with non-small cell lung cancer. Limitations There may be limitations in getting candidate hits that overlap in all mice in our first replicate. This can be remedied by conducting the in vivo screen in at least three biological replicates. Conclusion To the best of our knowledge, this is the first genome-wide in vivo CRISPR activation screen searching for drivers of LBM using a PDX animal model. This study can provide a framework to gain a deeper understanding of the regulators of BM formation which will hopefully lead to targeted drug discovery.

scholarly journals Bevacizumab suppresses the growth of established non-small-cell lung cancer brain metastases in a hematogenous brain metastasis model

2019 ◽  
Vol 37 (1) ◽  
pp. 199-207
Author(s):  
Chinami Masuda ◽  
Masamichi Sugimoto ◽  
Daiko Wakita ◽  
Makoto Monnai ◽  
Chisako Ishimaru ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Brain Metastasis ◽  
Brain Metastases ◽  
Small Cell Lung Cancer ◽  
Cell Lung Cancer ◽  
Small Cell ◽  
Nsclc Cell Line ◽  
Small Cell Lung ◽  
The Brain

AbstractBrain metastases are common in patients with non-small-cell lung cancer (NSCLC). The efficacy of bevacizumab, an anti-vascular endothelial growth factor (VEGF) humanized antibody, has been demonstrated in patients with nonsquamous NSCLC. We established a transplantable NSCLC cell line (Nluc-H1915) that stably expresses NanoLuc® reporter and confirmed the correlation between total Nluc activity in tumor and tumor volume in vivo. SCID mice inoculated with these cells through the internal carotid artery formed reproducible brain metastases, in which human VEGF was detected. Next, after metastases were established in the model mice (15–17 days), they were intraperitoneally administered weekly doses of human immunoglobulin G (HuIgG) or bevacizumab. Nluc activity in the brain was significantly lower in bevacizumab-treated mice than in HuIgG-treated mice. Additionally, bevacizumab concentration in the brain was higher in mice with brain metastasis than in normal mice, and bevacizumab was primarily observed in brain metastasis lesions. The microvessel density in brain metastasis was lower in bevacizumab-treated mice than in HuIgG-treated mice. We believe bevacizumab’s anti-proliferative effect on brain metastasis is due to anti-angiogenic activity achieved by its penetration into brain metastases; this suggests that a bevacizumab-containing regimen may be a promising treatment option for patients with NSCLC brain metastasis.

scholarly journals STEM-23. METASTATIC BRAIN TUMOR IMAGING THROUGH TARGETED PEPTIDES ISOLATED VIA PHAGE DISPLAY BIOPANNING AGAINST BRAIN METASTASIS-INITIATING CELLS

2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi238-vi238
Author(s):  
JongMyung Kim ◽  
James Liu
Keyword(s):  
Lung Cancer ◽  
Brain Metastasis ◽  
Brain Metastases ◽  
Phage Display ◽  
Tumor Imaging ◽  
Mesenchymal Transition ◽  
Phage Display Biopanning ◽  
In Vivo Phage Display

Abstract To effectively target metastatic brain tumors (MBTs), the paradigm of initiating treatment against MBTs following detection on clinical imaging needs to be shifted to an understanding of the mechanisms that drive the formation and maintenance of brain metastasis-initiating cells (BMICs). Targeting this tumor sub-population, which may form as a result of activation of the epithelial-mesenchymal transition, may allow for more effective means of understanding and targeting brain metastases. In order to isolate BMICs, we have harvested cells from patient derived MBTs originating from lung cancer and cultured the cells using stem cell media conditions. We then performed in vitro and in vivo phage display biopanning to isolate 12-amino acid length peptides that specifically target BMICs. Several peptides were isolated from both in vitro and in vivo biopanning strategies. Of the peptides recovered, one peptide, LBM4, demonstrated specific binding to MBT cells over primary lung cancer cells in vitro through flow cytometry analysis and immunocytochemistry. Fluorescent tagged LBM4 intravenously injected into mice harboring intracranial brain metastases demonstrated peptide localization to the tumor within the intracranial cavity visualized with live animal imaging. Peptide imaging of tumor corresponded to MRI imaging confirming that the peptides could serve as an alternative to tumor imaging, with the potential for greater sensitivity resulting from the cellular targeting of MBTs. Our results demonstrate that we can use a combination of in vitro and in vivo phage display biopanning to isolate cell specific targeting peptides. MBT targeting peptides can potentially result in a shifting of the clinical treatment paradigm of brain metastases, through the development of more effective targeted therapeutics aimed at BMICs, as well as improving detection of MBT cells which may result in earlier tumor visualization, as well as delineation of tumor recurrence versus radiation effects.

scholarly journals NGMA-5. An in vivo functional genomics screen to identify novel drivers of lung-to-brain metastasis

2021 ◽  
Vol 3 (Supplement_2) ◽  
pp. ii5-ii5
Author(s):  
Nikoo Aghaei ◽  
Fred C Lam ◽  
Ekkhard Kasper ◽  
Chitra Venugopal ◽  
Sheila Singh
Keyword(s):  
Lung Cancer ◽  
Brain Metastasis ◽  
Brain Metastases ◽  
Small Cell Lung Cancer ◽  
Cell Lung Cancer ◽  
Small Cell ◽  
Small Cell Lung ◽  
Genome Wide ◽  
Crispr Activation

Abstract Introduction Brain metastases, the most common tumors of the central nervous system, occur in approximately 20% of primary adult cancers. In particular, 40% of patients with non-small cell lung cancer develop brain metastasis. As systemic therapies for the treatment of non-small cell lung cancer become increasingly effective at controlling primary disease, patients are ironically succumbing to their brain metastases. This highlights a large unmet need to develop novel targeted therapies for the treatment of lung-to-brain metastases (LBM). We hypothesize that an in vivo functional genomic screen can identify novel genes that drive LBM. Methods To do this, we developed a patient-derived xenograft (PDX) mouse model of LBM using patient lung cancer cell lines. This PDX model of LBM enables the use of fluorescent and bioluminescent in vivo imaging to track the progression of lung tumor and brain metastases. Results We have performed an in vivo genome-wide CRISPR activation screening to identify novel drivers of LBM. We will derive candidate genes through mouse brain and lung tissue sequencing after mice reach endpoint. Expected Area of findings This platform will lead to potential therapeutic targets to prevent the formation of LBM and prolong the survival of patients with non-small cell lung cancer. Conclusion To the best of our knowledge, this is the first genome-wide in vivo CRISPR activation screen searching for drivers of LBM using a PDX animal model. This study can provide a framework to gain a deeper understanding of the regulators of BM formation which will hopefully lead to targeted drug discovery.

scholarly journals Synergy of nanodiamond–doxorubicin conjugates and PD-L1 blockade effectively turns tumor-associated macrophages against tumor cells

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Hua-Zhen Xu ◽  
Tong-Fei Li ◽  
Chao Wang ◽  
Yan Ma ◽  
Yan Liu ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Tumor Cell ◽  
Cancer Cells ◽  
Tumor Cells ◽  
Lung Cancer Cells ◽  
Dependent Manner ◽  
Tumor Associated Macrophages ◽  
M1 Type

Abstract Background Tumor-associated macrophages (TAMs) are the most abundant stromal cells in the tumor microenvironment. Turning the TAMs against their host tumor cells is an intriguing therapeutic strategy particularly attractive for patients with immunologically “cold” tumors. This concept was mechanistically demonstrated on in vitro human and murine lung cancer cells and their corresponding TAM models through combinatorial use of nanodiamond-doxorubicin conjugates (Nano-DOX) and a PD-L1 blocking agent BMS-1. Nano-DOX are an agent previously proved to be able to stimulate tumor cells’ immunogenicity and thereby reactivate the TAMs into the anti-tumor M1 phenotype. Results Nano-DOX were first shown to stimulate the tumor cells and the TAMs to release the cytokine HMGB1 which, regardless of its source, acted through the RAGE/NF-κB pathway to induce PD-L1 in the tumor cells and PD-L1/PD-1 in the TAMs. Interestingly, Nano-DOX also induced NF-κB-dependent RAGE expression in the tumor cells and thus reinforced HMGB1’s action thereon. Then, BMS-1 was shown to enhance Nano-DOX-stimulated M1-type activation of TAMs both by blocking Nano-DOX-induced PD-L1 in the TAMs and by blocking tumor cell PD-L1 ligation with TAM PD-1. The TAMs with enhanced M1-type repolarization both killed the tumor cells and suppressed their growth. BMS-1 could also potentiate Nano-DOX’s action to suppress tumor cell growth via blocking of Nano-DOX-induced PD-L1 therein. Finally, Nano-DOX and BMS-1 achieved synergistic therapeutic efficacy against in vivo tumor grafts in a TAM-dependent manner. Conclusions PD-L1/PD-1 upregulation mediated by autocrine and paracrine activation of the HMGB1/RAGE/NF-κB signaling is a key response of lung cancer cells and their TAMs to stress, which can be induced by Nano-DOX. Blockade of Nano-DOX-induced PD-L1, both in the cancer cells and the TAMs, achieves enhanced activation of TAM-mediated anti-tumor response. Graphic abstract

scholarly journals High-speed volumetric two-photon fluorescence imaging of neurovascular dynamics

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Jiang Lan Fan ◽  
Jose A. Rivera ◽  
Wei Sun ◽  
John Peterson ◽  
Henry Haeberle ◽  
...  
Keyword(s):  
Blood Flow ◽  
High Speed ◽  
Laser Scanning ◽  
Three Dimensional ◽  
Laser Scanning Microscopy ◽  
Fluorescence Signal ◽  
Imaging Method ◽  
Spatiotemporal Resolution ◽  
Two Photon

AbstractUnderstanding the structure and function of vasculature in the brain requires us to monitor distributed hemodynamics at high spatial and temporal resolution in three-dimensional (3D) volumes in vivo. Currently, a volumetric vasculature imaging method with sub-capillary spatial resolution and blood flow-resolving speed is lacking. Here, using two-photon laser scanning microscopy (TPLSM) with an axially extended Bessel focus, we capture volumetric hemodynamics in the awake mouse brain at a spatiotemporal resolution sufficient for measuring capillary size and blood flow. With Bessel TPLSM, the fluorescence signal of a vessel becomes proportional to its size, which enables convenient intensity-based analysis of vessel dilation and constriction dynamics in large volumes. We observe entrainment of vasodilation and vasoconstriction with pupil diameter and measure 3D blood flow at 99 volumes/second. Demonstrating high-throughput monitoring of hemodynamics in the awake brain, we expect Bessel TPLSM to make broad impacts on neurovasculature research.

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