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

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.

2019 ◽  
Vol 1 (Supplement_1) ◽  
pp. i4-i4
Author(s):  
JongMyung Kim ◽  
James Liu

Abstract To effectively target metastatic brain tumors (MBTs), the paradigm of treating MBTs after visualization 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 from activation of epithelial-mesenchymal transition, may allow for more effective means of isolating and targeting brain metastasis. In order to isolate BMICs, we have harvested cells from patient derived MBTs originating from lung cancer and cultured the cells using serum-free media conditions. In vivo phage display biopanning was used to isolate 12-amino acid length peptides that specifically target BMICs. Of the peptides recovered, one peptide, LBM4, was tested for specificity of binding to MBTs through in vitro and in vivo binding assays. When comparing patient derived metastatic brain tumors cells against brain metastasis cell lines, we found that both types of cells demonstrated similar morphology when grown in serum media conditions, but when grown in serum-free media, both demonstrated a tumor sphere morphology, similar to a stem cell-like state. 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 BM demonstrated peptide localization to the tumor within the intracranial cavity visualized with live animal imaging. In vivo phage display biopanning is an effective tool that is able 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.


2015 ◽  
Vol 17 (suppl 5) ◽  
pp. v59.1-v59
Author(s):  
Ping Huang ◽  
Qiulian Wu ◽  
Jeremy Rich ◽  
James Liu

Cancers ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 265 ◽  
Author(s):  
Shang-Gin Wu ◽  
Tzu-Hua Chang ◽  
Yi-Nan Liu ◽  
Jin-Yuan Shih

Tumor metastasis is a hallmark of cancer, with distant metastasis frequently developing in lung cancer, even at initial diagnosis, resulting in poor prognosis and high mortality. However, available biomarkers cannot reliably predict cancer spreading sites. The metastatic cascade involves highly complicated processes including invasion, migration, angiogenesis, and epithelial-to-mesenchymal transition that are tightly controlled by various genetic expression modalities along with interaction between cancer cells and the extracellular matrix. In particular, microRNAs (miRNAs), a group of small non-coding RNAs, can influence the transcriptional and post-transcriptional processes, with dysregulation of miRNA expression contributing to the regulation of cancer metastasis. Nevertheless, although miRNA-targeted therapy is widely studied in vitro and in vivo, this strategy currently affords limited feasibility and a few miRNA-targeted therapies for lung cancer have entered into clinical trials to date. Advances in understanding the molecular mechanism of metastasis will thus provide additional potential targets for lung cancer treatment. This review discusses the current research related to the role of miRNAs in lung cancer invasion and metastasis, with a particular focus on the different metastatic lesions and potential miRNA-targeted treatments for lung cancer with the expectation that further exploration of miRNA-targeted therapy may establish a new spectrum of lung cancer treatments.


2019 ◽  
Vol 97 (6) ◽  
pp. 767-776 ◽  
Author(s):  
Yufu Tang ◽  
Lijian Wu ◽  
Mingjing Zhao ◽  
Guangdan Zhao ◽  
Shitao Mao ◽  
...  

Long noncoding RNA small nucleolar RNA host gene 4 (SNHG4) is usually up-regulated in cancer and regulates the malignant behavior of cancer cells. However, its role in lung cancer remains elusive. In this study, we silenced the expression of SNHG4 in NCI-H1437 and SK-MES-1, two representative non-small-cell lung cancer cell lines, by transfecting them with siRNA (small interfering RNA) that specifically targets SNHG4. We observed significantly inhibited cell proliferation in vitro and reduced tumor growth in vivo after SNHG4 silencing. SNHG4 knockdown also led to cell cycle arrest at the G1 phase, accompanied with down-regulation of cyclin-dependent kinases CDK4 and CDK6. The migration and invasiveness of these two cell lines were remarkably inhibited after SNHG4 silencing. Moreover, our study revealed that the epithelial–mesenchymal transition (EMT) of lung cancer cells was suppressed by SNHG4 silencing, as evidenced by up-regulated E-cadherin and down-regulated SALL4, Twist, and vimentin. In addition, we found that SNHG4 silencing induced up-regulation of miR-98-5p. MiR-98-5p inhibition abrogated the effect of SNHG4 silencing on proliferation and invasion of lung cancer cells. In conclusion, our findings demonstrate that SNHG4 is required by lung cancer cells to maintain malignant phenotype. SNHG4 probably exerts its pro-survival and pro-metastatic effects by sponging anti-tumor miR-98-5p.


Author(s):  
Lin-lin Zhang ◽  
Qi Li ◽  
Dian-sheng Zhong ◽  
Wei-jian Zhang ◽  
Xiao-jie Sun ◽  
...  

BackgroundHistone deacetylase 1 (HDAC1) is essential in the malignant progression of tumors. However, there is no obvious relationship between the expression of HDAC1 and the survival of lung cancer patients. Herein, we explored the involvement of minichromosome maintenance complex component 5 (MCM5) and HDAC1 interaction in the epithelial-to-mesenchymal transition (EMT)-dependent malignant progression of lung cancer.MethodsWe analyzed the expression of MCM5 and HDAC1 in The Cancer Genome Atlas database and clinical samples, as well as their impact on patient survival. Cell and animal experiments were performed to verify the promotion of EMT in lung cancer cells mediated by MCM5 and HDAC1.ResultsWe found that lung adenocarcinoma patients with high expression of MCM5 and HDAC1 had poor survival time. Overexpression of MCM5 and HDAC1 in A549 and H1975 cells can promote proliferation and invasion in vitro and tumor growth and metastasis in vivo. Moreover, astragaloside IV can block the interaction between HDAC1 and MCM5, which can then inhibit the malignant progression of lung cancer in vivo and in vitro.ConclusionThe interaction between MCM5 and HDAC1 aggravated the EMT-dependent malignant progression of lung cancer. Astragaloside IV can block the interaction between MCM5 and HDAC1 to inhibit the progression of lung cancer.


2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Yanyang Cao ◽  
Xuan Wang ◽  
Yunsheng Li ◽  
Maria Evers ◽  
Haiyun Zhang ◽  
...  

Abstract Background Extracellular ATP (eATP) was shown to induce epithelial–mesenchymal transition (EMT), a very important early process in metastasis, in cancer cells via purinergic receptor signaling. However, the exact induction mechanisms are far from fully known. We previously described that eATP is internalized by cancer cells in vitro and in vivo by macropinocytosis in human non-small cell lung cancer A549 and other cancer cells, drastically elevates intracellular ATP levels, enhances cell proliferation and resistance to anticancer drugs. In this study, we tested the hypothesis that eATP and macropinocytosis-internalized eATP also induces EMT and other early steps of metastasis. Methods Floating cells, fencing, and transwell assays were used to show that ATP induces cell detachment, new colony formation, migration and invasion in human A549 and other lung cancer cells. Western blots were used to detect ATP-induced changes in EMT-related proteins; Confocal microscopy was used to demonstrate ATP-induced metastasis-related cell morphological changes. Inhibitors and siRNA knockdowns were used to determine P2X7’s involvement in the ATP-induced EMT. CRISPR–Cas9 knockout of the SNX5 gene was used to identify macropinocytosis’ roles in EMT and cancer cell growth both in vitro and in vivo. Student t-test and one-way ANOVA were used to determine statistical significance, P < 0.05 was considered significant. Results eATP potently induces expression of matrix metallopeptidases (MMPs), and detachment, EMT, migration, and invasion of lung cancer cells. The induction was independent of TGF-β and semi-independent of P2X7 activation. eATP performs these functions not only extracellularly, but also intracellularly after being macropinocytically internalized to further enhance P2X7-mediated EMT, filopodia formation and other early steps of metastasis. The knockout of macropinocytosis-associated SNX5 gene significantly reduces macropinocytosis, slows down tumor growth, and changes tumor morphology in nude mice. Conclusions Collectively, these results show that eATP's functions in these processes not only from outside of cancer cells but also inside after being macropinocytotically internalized. These findings shed light on eATP’s initiator and effector roles in almost every step in early metastasis, which calls for rethinking and rebalancing energy equations of intracellular biochemical reactions and the Warburg effect, and identifies eATP and macropinocytosis as novel targets for potentially slowing down EMT and preventing metastasis.


2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii196-ii196
Author(s):  
Marine Potez ◽  
Jongmyung Kim ◽  
Chunhua She ◽  
Neelkamal Chaudhary ◽  
James Liu

Abstract Glioblastoma (GBM) is the most aggressive primary brain tumor with high mortality rates and resistance to conventional therapy. Glioma stem cells (GSCs) comprise a sub-population of glioma tumor cells with the ability of self-renewal and tumor recapitulation, and may be responsible for GBM’s treatment resistant properties. Identification of surface receptors that are novel and specific to GSCs may be the key to the development of effective therapeutic strategies. We have selected a GSC specific targeting peptide isolated through in vitro and in vivo phage display biopanning. This screening technique allowed us to determine a peptide (GBM-IC2) which binds specifically to GSCs in vitro, and to GBM tissue in vivo. Although this screening process allows for isolation of cell specific targeting peptides, it does so without identification of the cellular binding partner. Given the specificity of the peptide, identification of the cellular receptor may allow for discovery of novel markers to identify GSCs. To identify the peptide binding partner of GBM-IC2, the biotinylated peptide was incubated with GSC protein lysate. The peptide, along with its binding partner, was isolated using streptavidin agarose resin. The binding partner protein was then identified using mass spectroscopy. This revealed N-cadherin (CDH2) as a potential binding partner for the GBM-IC2 peptide. GBM-IC2 demonstrated specificity for targeting CDH2 compared to control peptide using ELISA. Lentiviral induced overexpression of CDH2 in HEK293 cells allowed for GBM-IC2 peptide binding. Competition assay was performed by applying anti-CDH2 antibody to GBM-IC2 peptide and GSCs in culture. Application of anti-CDH2 antibody decreased peptide binding to GSCs, confirming CDH2 as the binding partner for GBM-IC2. These results demonstrate that cell specific targeting peptides isolated through phage display may lead to the isolation of novel cell specific proteins through immunoprecipitation isolation and mass spectroscopy analysis.


2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi198-vi199
Author(s):  
Mao Li ◽  
Markus Schweiger ◽  
Daniel Ryan ◽  
Ichiro Nakano ◽  
Litia Carvalho ◽  
...  

Abstract Olfactory receptors (ORs), responsible for the sense of smell, play an essential role in various physiological processes outside the nasal epithelium, including cancer. In breast cancer, however, the expression and function of ORs remain understudied. We established a breast cancer metastasis model by intracardiac injection of MDA-MB-231 (231P) in immunocompromised mice and produced a series of derivative cell lines from developed metastatic sites, including the brain-seeking clone (231Br). We examined the significance of ORs transcript abundance in primary and metastatic breast cancer to different tissues, including the brain, bone, and lung. While 20 OR transcripts were differentially expressed in distant metastases, OR5B21 displayed high expression in all three metastatic sites with respect to the primary tumor, especially in brain metastasis with 13 fold higher than the primary site. Metastatic clones showed distinguishing higher invasion biological characteristics compared to parental cells in vivo and in vitro. Knockdown of OR5B21 significantly decreased the invasion and migration of MDA-MB-231 Brain-seeking metastatic cell as well as metastasis to different organs, including the brain, while overexpression of OR5B21 had the opposite effect. Mechanistically, OR5B21 expression was associated with epithelial to mesenchymal transition through the STAT3/NFkB/CEBPβ signaling pathway. We propose OR5B21 (and potentially other ORs) as a novel oncogene contributing to breast cancer brain metastasis and a potential target for adjuvant therapy.


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