• BMB Reports
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• v.53 no.12
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• pp.646-651
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• 2020

Bone resorption is linked to bone formation via temporal and spatial coupling within the remodeling cycle. Several lines of evidence point to the critical role of coupling factors derived from pre-osteoclasts (POCs) during the regulation of bone marrow-derived mesenchymal stem cells (BMMSCs). However, the role of glial cell-derived neurotrophic factor (GDNF) in BMMSCs is not completely understood. Herein, we demonstrate the role of POC-derived GDNF in regulating the migration and osteogenic differentiation of BMMSCs. RNA sequencing revealed GDNF upregulation in POCs compared with monocytes/macrophages. Specifically, BMMSC migration was inhibited by a neutralizing antibody against GDNF in pre-osteoclast-conditioned medium (POC-CM), whereas treatment with a recombinant GDNF enhanced migration and osteogenic differentiation. In addition, POC-CM derived from GDNF knock-downed bone marrow macrophages suppressed BMMSC migration and osteogenic differentiation. SPP86, a small molecule inhibitor, inhibits BMMSC migration and osteogenic differentiation by targeting the receptor tyrosine kinase RET, which is recruited by GDNF into the GFRα1 complex. Overall, this study highlights the role of POC-derived GDNF in BMMSC migration and osteogenic differentiation, suggesting that GDNF regulates bone metabolism.

• Korean Journal of Veterinary Research
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• v.61 no.1
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• pp.10.1-10.11
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• 2021

The purpose of this retrospective study was to provide additional data on the use of toceranib in a wide variety of tumor types in small breed dogs, especially < 8 kg (except 5 dogs). This was a retrospective study of 31 dogs with malignant tumors treated with a 2.5 mg/kg median dose of toceranib (Palladia; Zoetis, USA) on a Monday-Wednesday-Friday schedule. Clinical benefit was observed in 13 of 15 dogs (86.7%, 3 with complete response, 4 with partial response, 6 with stable disease) with gross disease. Distant metastasis, response to treatment, and treatment setting were significantly associated with survival time. Negative prognostic factors were multiple chemotherapy and distant metastasis (affecting progression-free survival [PFS]), surgery, regional enlarged lymph nodes, underlying disease, and toxicity (affecting median survival time [MST]). Positive prognostic factors were epithelial and round cell tumor (affecting PFS), epithelial tumor, microscopic disease, no evidence of disease response, and stable disease (MST). In conclusion, a clinical benefit from toceranib treatment was noted in most of the dogs with gross disease in our study. This study suggested that the toceranib is probably selective treatment to various tumor types in small breed dogs.

• Journal of Veterinary Clinics
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• v.38 no.4
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• pp.184-188
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• 2021

A 10-year-old spayed female Maltese with a history of vomiting and lethargy was referred to the hospital. Physical examination revealed dehydration and severe pain following abdominal palpation. A large mass was observed in the cranial abdomen through radiography and ultrasonography. Laparotomy was performed to find the origin of the mass. The mass was about 8 cm originating from the cecum and subsequently removed. Histopathologic evaluation revealed that the cecal mass was suspected to be a mesenchymal-derived tumor. Through immunohistochemistry, the mass was diagnosed as a gastrointestinal stromal tumor (GIST) based on the c-kit expression. Given its recurrence, postoperative preventive therapy was initiated with masitinib mesylate, which is a tyrosine kinase inhibitor. The animal did not show any side effects during the medication period. After 6 months of therapy, it was well controlled without any recurrence. In this case, we introduced a novel postoperative management of GIST using masitinib mesylate.

• IMMUNE NETWORK
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• v.20 no.1
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• pp.11.1-11.14
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• 2020

Most patients with hepatocellular carcinoma (HCC) are diagnosed at an advanced stage of disease. Until recently, systemic treatment options that showed survival benefits in HCC have been limited to tyrosine kinase inhibitors, antibodies targeting oncogenic signaling pathways or VEGF receptors. The HCC tumor microenvironment is characterized by a dysfunction of the immune system through multiple mechanisms, including accumulation of various immunosuppressive factors, recruitment of regulatory T cells and myeloid-derived suppressor cells, and induction of T cell exhaustion accompanied with the interaction between immune checkpoint ligands and receptors. Immune checkpoint inhibitors (ICIs) have been interfered this interaction and have altered therapeutic landscape of multiple cancer types including HCC. In this review, we discuss the use of anti-PD-1, anti-PD-L1, and anti-CTLA-4 antibodies in the treatment of advanced HCC. However, ICIs as a single agent do not benefit a significant portion of patients. Therefore, various clinical trials are exploring possible synergistic effects of combinations of different ICIs (anti-PD-1/PD-L1 and anti-CTLA-4 antibodies) or ICIs and target agents. Combinations of ICIs with locoregional therapies may also improve therapeutic responses.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.6
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• pp.763-770
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• 1998

A number of substances involved in the proliferation and differentiation of the tracheobronchial epithelium have been identified. The defects in the control of the proliferation and differentiation of tracheobronchial epithelial cells appear to constitute crucial steps in the transition of normal cells to neoplastic ones. Endothelin-1 is produced by tracheal epithelial cells, and its receptors are present in tracheal epithelial cells. However, the effect of endothelin-1 on the proliferation and differentiation of tracheal epithelial cells has not been clearly elucidated. This study was undertaken to investigate these actions of endothelin-1 in primary cultured cells of rat tracheal epithelia. Endothelin-1 stimulated proliferation of tracheal epithelial cells 1.5-fold when compared with that of control cells. Endothelin-1 increased mitogen-activated protein kinase (MAPK) activity. Herbimycin A, a tyrosine kinase inhibitor, inhibited endothelin-1-induced proliferation of epithelial cells. The treatment of endothelin-1 during the primary culture of tracheal epithelial cells increased AB-PAS-stained cell population and ciliated cell population 6.5 fold and 1.5 fold, respectively, when compared with those in control cells. The responsiveness to carbachol and forskolin in the $Cl^-$ secretion was increased 1.7 and 1.9 fold, respectively, in the endothelin-treated epithelial cells. These results indicated that endothelin-1 increases proliferation via MAPK pathway and stimulates differentiation to secretory and ciliated cells in rat tracheal epithelial cells.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7501-7508
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• 2013

Background: Chronic myeloid leukemia (CML) is a myeloproliferative disorder of hematopoietic stem cell scarrying the Philadelphia (Ph) chromosome and an oncogenic BCR-ABL1 fusion gene. The tyrosine kinase inhibitor (TKI) of BCR-ABL1 kinase is a treatment of choice for control of CML. Objective: Recent studies have demonstrated that miRNAs within exosomes from cancer cells play crucial roles in initiation and progression. This study was performed to assess miRNAs within exosomes of K562 cells. Methods: miRNA microarray analysis of K562 cells and K562 cell-derived exosomes was conducted with the 6th generation miRCURYTM LNA Array (v.16.0). Gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were also carried out. GO terms and signaling pathways were categorized into 66 classes (including homophilic cell adhesion, negative regulation of apoptotic process, cell adhesion) and 26 signaling pathways (such as Wnt). Results: In exosomes, 49 miRNAs were up regulated as compared to K562 cells, and two of them were further confirmed by quantitative real-time PCR. There are differentially expressed miRNAs between K562 cell derived-exosomes and K562 cells. Conclusion: Selectively expressed miRNAs in exosomes may promote the development of CML via effects on interactions (e.g. adhesion) of CML cells with their microenvironment.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.3
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• pp.1787-1790
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• 2013

This study evaluated the effects of ZD1839, an orally active, selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, on nasopharyngeal carcinoma (NPC) both in vitro and in vivo. Influence of ZD1839 alone or combined with cisplatin on the NPC cell line CNE2 was detected by MTT assay with flow cytometry assessment of cell cycle distribution and apoptosis rates. Nude mice NPC xenografts were also used to evaluate the effects of ZD1839 alone or combined with cisplatin. The Student's t test evaluated statistical significance. ZD1839 alone or combined with cisplatin inhibited CNE2 cell line proliferation. ZD1839 induced CNE2 cell cycle arrest in the G1 phase, and higher concentrations induced apoptosis. Xenograft tumors were significantly smaller when treated with 200 mg/kg ZD1839, cisplatin, or cisplatin combined with 100 mg/kg ZD1839 than untreated controls. ZD1839 (200 mg/kg) alone showed good tumor inhibition effects, reduction of tumor weights, and smaller tumor volume without loss of body weight. ZD1839 (200 mg/kg) might provide a good and effective therapeutic reagent for NPC.

• Animal cells and systems
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• v.12 no.1
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• pp.15-21
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• 2008

Nitric oxide(NO) has been known to play important roles in numerous physiologic processes including neurotransmission, vasorelaxation, and cellular apoptosis. Using a mouse cDNA gene chip, we examined expression patterns and time course of NO-dependent genes in mouse macrophage RAW264.7 cells. Genes shown to be upregulated more than two fold or at least at two serial time points were further selected and validated by RT-PCR. Finally, 81 selected genes were classified by function as signaling, apoptosis, inflammation, transcription, translation, ionic homeostasis and metabolism. Among those, genes related with signaling, apoptosis and inflammation, such as guanylate cyclase 1, soluble, alpha3(Gucy1a3); protein kinase C, alpha($Pkc{\alpha}$); lymphocyte protein tyrosine kinase(Lck); BCL2/adenovirus E1B 19 kDa-interacting protein(Bnip3); apoptotic protease activating factor 1(Apaf1); X-linked inhibitor of apoptosis(Xiap); cyclin G1(Ccng1); chemokine(C-C motif) ligand 4(Ccl4); B cell translocation gene 2, anti-proliferative(Btg2); lysozyme 2(Lyz2); secreted phosphoprotein 1(Spp1); heme oxygenase(decycling) 1(Hmox1); CD14 antigen(Cd14); and granulin(Grn) may play important roles in NO-dependent responses in murine macrophages.

• Journal of Microbiology and Biotechnology
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• v.31 no.4
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• pp.559-569
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• 2021

As one of the major types of lung cancer, non-small cell lung cancer (NSCLC) accounts for the majority of cancer-related deaths worldwide. Treatments for NSCLC includes surgery, chemotherapy, and targeted therapy. Among the targeted therapies, resistance to inhibitors of the epidermal growth factor receptor (EGFR) is common and remains a problem to be solved. MET (hepatocyte growth factor receptor) amplification is one of the major causes of EGFR-tyrosine kinase inhibitor (TKI) resistance. Therefore, there exists a need to find new and more efficacious therapies. Deoxypodophyllotoxin (DPT) extracted from Anthriscus sylvestris roots exhibits various pharmacological activities including anti-inflammation and anti-cancer effects. In this study we sought to determine the anti-cancer effects of DPT on HCC827GR cells, which are resistant to gefitinib (EGFR-TKI) due to regulation of EGFR and MET and their related signaling pathways. To identify the direct binding of DPT to EGFR and MET, we performed pull-down, ATP-binding, and kinase assays. DPT exhibited competitive binding with ATP against the network kinases EGFR and MET and reduced their activities. Also, DPT suppressed the expression of p-EGFR and p-MET as well as their downstreat proteins p-ErbB3, p-AKT, and p-ERK. The treatment of HCC827GR cells with DPT induced high ROS generation that led to endoplasmic-reticulum stress. Accordingly, loss of mitochondrial membrane potential and apoptosis by multi-caspase activation were observed. In conclusion, these results demonstrate the apoptotic effects of DPT on HCC827GR cells and signify the potential of DPT to serve as an adjuvant anti-cancer drug by simultaneously inhibiting EGFR and MET.

• IMMUNE NETWORK
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• v.7 no.4
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• pp.203-208
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• 2007

Background: Angiogenesis mediated by VEGF constitutes a new target for anti-cancer therapy which has explored through different ways of intervention aiming at the blocking of the tumoral angiogenesis. In the present study, we developed the assays by which efficacies of anti-VEGF inhibitor candidates are evaluated at the various levels. Methods & Results: First, we developed two sandwich ELISAs using coated anti-VEGF Ab and soluble Flt-1 receptor fusion protein (sFlt-1/Fc). As low as 200 pg/ml of hVEGF diluted in human sera was detectable by these assays. In addition, we found that VEGF inhibitors ($2{\mu}g/ml$ of either anti-VEGF Ab or sFlt-1/Fc) completely block 5 ng/ml VEGF in these ELISAs. Subsequently, two bioassays, wound healing and HUVEC tube formation assays, revealed that anti-VEGF Ab $(1{\mu}g/ml)$ & sFlt-1/Fc Ab $(1{\mu}g/ml)$, or SU5416 (VEGFR tyrosine kinase inhibitor, $1{\mu}M$) prevents the activity of VEGF $(1{\sim}10ng/ml)$. Finally, secretion of MMP-9 by VEGF-stimulated macrophages was abolished by treatment of anti-VEGF Ab $(1{\mu}g/ml)$ in gelatin zymography. Conclusion: ELISAs together with bioassays developed in this study are appropriate for evaluation of the efficacy of inhibitors of VEGF.