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1.
Biochem Biophys Res Commun ; 619: 110-116, 2022 09 03.
Article in English | MEDLINE | ID: mdl-35753218

ABSTRACT

Chemotherapy induces tumor cell death and inhibits tumor progression, but the accompanying immune responses in the surrounding dying tissue cause significant inflammation. These responses, such as excessive neutrophil infiltration into tumor tissue, are the main causes of resistance to anticancer treatment. The development of drugs that reduce neutrophil infiltration into tumors is necessary to increase the anticancer effect of chemotherapy. Here, we show that the antitumor effect of the chemotherapy AC regimen (Adriamycin and cyclophosphamide) was increased by 1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol (PLAG) cotreatment in the MDA-MB-231 triple-negative breast cancer xenograft mouse model. Tumor growth was inhibited up to 56% in mice treated with AC and inhibited up to 94% in mice cotreated with AC and PLAG. Side effects of chemotherapy, such as a reduction in body weight, were alleviated in mice cotreated with AC and PLAG. Excessive neutrophil infiltration caused by the AC regimen was successfully cleared in mice cotreated with AC and PLAG. We conclude that PLAG inhibits excessive neutrophil infiltration that aids tumor growth. Reduced neutrophils and increased lymphocytes in PLAG-treated mice can maximize the antitumor effect of the AC regimen and inhibit tumor growth.


Subject(s)
Doxorubicin , Triple Negative Breast Neoplasms , Animals , Cell Line, Tumor , Cyclophosphamide/therapeutic use , Disease Models, Animal , Doxorubicin/therapeutic use , Heterografts , Humans , Mice , Triple Negative Breast Neoplasms/drug therapy , Xenograft Model Antitumor Assays
2.
BMC Cancer ; 22(1): 727, 2022 Jul 04.
Article in English | MEDLINE | ID: mdl-35787261

ABSTRACT

BACKGROUND: The PD-L1 antibody is an immune checkpoint inhibitor (ICI) attracting attention. The third-generation anticancer drug has been proven to be very effective due to fewer side effects and higher tumor-specific reactions than conventional anticancer drugs. However, as tumors produce additional resistance in the host immune system, the effectiveness of ICI is gradually weakening. Therefore, it is very important to develop a combination therapy that increases the anticancer effect of ICI by removing anticancer resistance factors present around the tumor. METHODS: The syngeneic model was used (n = 6) to investigate the enhanced anti-tumor effect of PD-L1 antibody with the addition of PLAG. MB49 murine urothelial cancer cells were implanted into the C57BL/6 mice subcutaneously. PLAG at different dosages (50/100 mpk) was daily administered orally for another 4 weeks with or without 5 mpk PD-L1 antibody (10F.9G2). PD-L1 antibody was delivered via IP injection once a week. RESULTS: The aPD-L1 monotherapy group inhibited tumor growth of 56% compared to the positive group, while the PLAG and aPD-L1 co-treatment inhibited by 89%. PLAG treatment effectively reduced neutrophils infiltrating localized in tumor and converted to a tumor microenvironment with anti-tumor effective T-cells. PLAG increased tumor infiltration of CD8 positive cytotoxic T-cell populations while effectively inhibiting the infiltration of neoplastic T-cells such as CD4/FoxP3. Eventually, neutrophil-induced tumor ICI resistance was resolved by restoring the neutrophil-to-lymphocyte ratio to the normal range. In addition, regulation of cytokine and chemokine factors that inhibit neutrophil infiltration and increase the killing activity of cytotoxic T cells was observed in the tumors of mice treated with PLAG + aPD-L1. CONCLUSIONS: PLAG effectively turned the tumor-promoting microenvironment into a tumor-suppressing microenvironment. As a molecule that increases the anti-tumor effectiveness of aPD-L1, PLAG has the potential to be an essential and effective ICI co-therapeutic agent.


Subject(s)
Carcinoma, Transitional Cell , Urinary Bladder Neoplasms , Animals , Mice , B7-H1 Antigen , Carcinoma, Transitional Cell/drug therapy , Mice, Inbred C57BL , Neutrophil Infiltration , Tumor Microenvironment , Urinary Bladder Neoplasms/drug therapy
3.
Oral Dis ; 26(1): 111-121, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31677207

ABSTRACT

OBJECTIVE: This study was designed to investigate whether necroptosis is involved in the pathogenesis of chemoradiation-induced oral mucositis in a murine model and whether 1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol (PLAG) ameliorates this disorder. MATERIALS AND METHODS: A chemoradiation-induced oral mucositis model was established by treating mice with concurrent 5-fluorouracil (100 mg/kg, i.p.) and head and neck X-irradiation (20 Gy). Phosphate-buffered saline or PLAG (100 mg/kg or 250 mg/kg, p.o.) was administered daily. Body weights were recorded daily, and mice were sacrificed on Day 9 for tongue tissue analysis. RESULTS: On Day 9, chemoradiotherapy-treated (ChemoRT) mice had tongue ulcerations and experienced significant weight loss (Day 0:26.18 ± 1.41 g; Day 9:19.44 ± 3.26 g). They also had elevated serum macrophage inhibitory protein 2 (MIP-2) (control: 5.57 ± 3.49 pg/ml; ChemoRT: 130.14 ± 114.54 pg/ml) and interleukin (IL)-6 (control: 198.25 ± 16.91 pg/ml; ChemoRT: 467.25 ± 108.12 pg/ml) levels. ChemoRT-treated mice who received PLAG exhibited no weight loss (Day 0:25.78 ± 1.04 g; Day 9:26.46 ± 1.68 g) and had lower serum MIP-2 (4.42 ± 4.04 pg/ml) and IL-6 (205.75 ± 30.41 pg/ml) levels than ChemoRT-treated mice who did not receive PLAG. Tongue tissues of mice who received PLAG also displayed lower phosphorylation levels of necroptotic signalling proteins. CONCLUSION: 1-Palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol mitigated chemoradiation-induced oral mucositis by modulating necroptosis.


Subject(s)
Chemoradiotherapy/adverse effects , Diglycerides/pharmacology , Stomatitis/drug therapy , Animals , Chemokine CXCL2/blood , Fluorouracil/adverse effects , Interleukin-6/blood , Male , Mice , Mice, Inbred BALB C , Stomatitis/etiology
4.
Infect Immun ; 87(1)2019 01.
Article in English | MEDLINE | ID: mdl-30396896

ABSTRACT

Sialyllactose (SL) is a representative human milk oligosaccharide (HMO) of human breast milk. The roles of SL in infant brain development and immunity have been reported in previous studies. In this study, we identified the impact of SL on innate immunity. Our results showed that the administration of SL had significant efficacy on bacterial clearance in Pseudomonas aeruginosa K-infected mice. We also examined the role of SL in the human THP-1 macrophage-like cell line. SL effectively promoted receptor-mediated endocytosis and phagocytosis. Furthermore, SL accelerated the recruitment of Rac1 to the cell membrane, leading to the generation of reactive oxygen species for the elimination of phagocytosed bacteria. Our findings provide a new perspective on the role of SL in breast milk and suggest its application as a therapeutic agent to treat bacterial and viral infections.


Subject(s)
Immunologic Factors/administration & dosage , Lactose/analogs & derivatives , Phagocytosis/drug effects , Pseudomonas Infections/drug therapy , Animals , Disease Models, Animal , Humans , Immunologic Factors/pharmacology , Lactose/administration & dosage , Lactose/pharmacology , Male , Mice, Inbred BALB C , Models, Biological , THP-1 Cells , Treatment Outcome
5.
J Cell Biochem ; 118(10): 3372-3380, 2017 10.
Article in English | MEDLINE | ID: mdl-28300285

ABSTRACT

HX-1171 (1-O-hexyl-2,3,5-trimethylhydroquinone) is a novel synthesized vitamin E derivative, which reportedly has positive effects on various diseases and conditions, such as liver fibrosis, hepatic cirrhosis, and cancer. In this study, we analyzed the transcriptional activity induced by HX-1171. Results from reverse transcription polymerase chain reaction and promoter assays reveal that HX-1171 increased the expression of NQO1 and HMOX1, encoding antioxidant-related enzymes, in A549 human lung epithelial cells. The activity of nuclear factor-E2-related factor (Nrf2), a key transcriptional factor for antioxidative enzymes, was examined in HX-1171-treated cells. Confocal microscopy and Western blotting showed that HX-1171 effectively induced the nuclear translocation and transcriptional activity of Nrf2. We conclude that HX-1171, a novel Nrf2 activator, may be a promising therapeutic agent for oxidative stress-induced diseases. J. Cell. Biochem. 118: 3372-3380, 2017. © 2017 Wiley Periodicals, Inc.


Subject(s)
Cell Nucleus/metabolism , Gene Expression Regulation/drug effects , Heme Oxygenase-1/biosynthesis , Hydroquinones/pharmacology , NAD(P)H Dehydrogenase (Quinone)/biosynthesis , NF-E2-Related Factor 2/antagonists & inhibitors , A549 Cells , Active Transport, Cell Nucleus/drug effects , Active Transport, Cell Nucleus/genetics , Cell Nucleus/genetics , Heme Oxygenase-1/genetics , Humans , NAD(P)H Dehydrogenase (Quinone)/genetics , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Oxidative Stress/drug effects , Oxidative Stress/genetics
6.
J Cell Biochem ; 117(1): 172-9, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26096175

ABSTRACT

Genkwadaphnin (GD-1) is isolated from the flower buds of Daphne genkwa Siebold et Zuccarini (Thymelaeaceae), and it has been used as a traditional Korean and Chinese medicine. In this study, the authors observe that GD-1 inhibits the growth of the colon cancer cell line, SW620, through the up-regulation of p21 expression in a PRDM1-dependent manner. After treatment with GD-1, the transcriptional repressor PRDM1 is prominently induced in SW620 cells. Furthermore, GD-1 induce the phosphorylation of PKD1 and MEK and subsequently provide PRDM1 enhancement, resulting in the suppression of c-Myc expression and the up-regulation of p21. PKD1 knockdown using siRNA abrogates PRDM1 expression by GD-1 and subsequently disrupts the regulation of c-Myc and p21 expression. Treating SW620 cells with GD-1 inhibits cell-cycle progression and is characterized by the down-regulation of c-Myc followed by the up-regulation of p21 expression. The up-regulation of p21 by GD-1 induces the growth arrest of the SW620 colon cancer cell line. Based on these data, the authors propose that GD-1 has tumor-suppressor activity that may contribute to the anti-tumor effects of PRDM1 in colon cancer.


Subject(s)
Colonic Neoplasms/metabolism , Diterpenes/pharmacology , Repressor Proteins/metabolism , Apoptosis/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Cyclin-Dependent Kinase Inhibitor p21/metabolism , Gene Expression Regulation, Neoplastic/drug effects , Humans , Phosphorylation/drug effects , Positive Regulatory Domain I-Binding Factor 1
7.
J Sci Food Agric ; 96(8): 2635-40, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26282882

ABSTRACT

BACKGROUND: Euphorbia kansui, a traditional medical herb, has been shown to have anti-tumour and anti-viral activities. Previously, we have reported that E. kansui increases interferon-gamma (IFN-γ) production in natural killer (NK) cells. However, it is not clear how E. kansui regulates IFN-γ secretion by NK cells. RESULTS: In this study, E. kansui was separated into six individual compounds from the same chloroform fraction so that the activity of each compound could be compared. E. kansui compounds induced IFN-γ secretion through the phosphorylation of protein kinase D and IκB kinase pathways. Furthermore, E. kansui compounds activated the translocation of p65, a sub-unit of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), to the nucleus and induced NF-κB at the transcriptional level. CONCLUSION: These findings suggest that E. kansui enhances IFN-γ secretion through the NF-κB pathway in NK cells. © 2015 Society of Chemical Industry.


Subject(s)
Diterpenes/chemistry , Euphorbia/chemistry , Gene Expression Regulation/drug effects , Interferon-gamma/metabolism , NF-kappa B/metabolism , Active Transport, Cell Nucleus , Cell Line , Humans , Signal Transduction , Transcription, Genetic/drug effects
8.
Biochem Biophys Res Commun ; 450(2): 1115-9, 2014 Jul 25.
Article in English | MEDLINE | ID: mdl-24996181

ABSTRACT

Genkwadaphnin is a daphnane diterpene ester molecule isolated from the flower buds of Daphne genkwa. In the present study, we investigated the apoptosis-inducing effect of genkwadaphnin in squamous cell carcinoma (SCC) cells. Apoptosis was triggered in SCC12 cells following genkwadaphnin treatment in a time- and concentration-dependent manner. Genkwadaphnin treatment increased phosphorylation of c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK). Knockdown of JNK and p38 MAPK by recombinant adenovirus expressing microRNA (miR) resulted in significant inhibition of genkwadaphnin-induced apoptosis in SCC12 cells. Finally, pretreatment with the reactive oxygen species (ROS) scavenger N-acetylcysteine (NAC) markedly reduced SCC12 cell apoptosis, concomitant with significant inhibition of MAPK activation. These results indicate that genkwadaphnin has the potential to induce apoptosis in SCC cells, providing information on which to base further research with the aim of developing a cure for SCC.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Carcinoma, Squamous Cell/metabolism , Diterpenes/pharmacology , Reactive Oxygen Species/metabolism , Skin Neoplasms/metabolism , Carcinoma, Squamous Cell/pathology , Cell Line, Tumor , Enzyme Activation , Gene Knockdown Techniques , Humans , JNK Mitogen-Activated Protein Kinases/genetics , JNK Mitogen-Activated Protein Kinases/metabolism , Phosphorylation , Skin Neoplasms/pathology , p38 Mitogen-Activated Protein Kinases/genetics , p38 Mitogen-Activated Protein Kinases/metabolism
9.
Radiat Res ; 202(4): 706-718, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-39187264

ABSTRACT

Total-body irradiation (TBI) with gamma rays can damage organisms in various unexpected ways and trigger several organ dysfunction syndromes, such as acute radiation syndrome (ARS). Hematopoietic cells and enterocytes are particularly sensitive to radiation due to their self-renewal ability and rapid division, which leads to hematopoietic ARS (H-ARS) and gastrointestinal ARS (GI-ARS). We previously showed that a lipid-based small molecule, 1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol (PLAG), improved 30-day survival and alleviated H-ARS symptoms in BALB/c mice after a lethal dose (LD70/30) of gamma-ray TBI. In this study, we investigated the mitigating effects of PLAG on radiation-induced GI damage that occurs under the same conditions as H-ARS in BALB/c mice. Our study showed that PLAG facilitated the structural restoration of intestinal tissues by increasing villus height, crypt depth, crypt number, mucin-producing goblet cells, and proliferating cell nuclear antigen (PCNA)-positive crypt cells. PLAG significantly improved intestinal absorptive capacity and reduced intestinal injury-induced bacterial translocation. In addition, PLAG effectively inhibited radiation-induced necroptosis signaling activation in the intestinal crypt cells, which was responsible for sustained tissue damage and the release of high mobility group box 1 (HMGB1), a typical damage-associated molecular pattern. Overall, our findings support the radiation-mitigating potential of PLAG against GI-ARS after accidental radiation exposure.


Subject(s)
Acute Radiation Syndrome , Mice, Inbred BALB C , Whole-Body Irradiation , Animals , Whole-Body Irradiation/adverse effects , Acute Radiation Syndrome/drug therapy , Acute Radiation Syndrome/pathology , Mice , Diglycerides/pharmacology , Male , Gastrointestinal Tract/radiation effects , Gastrointestinal Tract/drug effects , Gastrointestinal Tract/pathology , Radiation-Protective Agents/pharmacology , Gamma Rays/adverse effects , Glycerides
10.
Biomed Pharmacother ; 178: 117269, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39137654

ABSTRACT

Excessive neutrophil infiltration into the tumor microenvironment (TME) is an important factor that contributes to tumor overgrowth and limited immunotherapy efficacy. Neutrophils activate various receptors involved in tumor progression, while suppressing the infiltration and activity of cytotoxic T cells and creating optimal conditions for tumor growth. Therefore, the appropriate control of neutrophil infiltration is an effective strategy for tumor treatment. In the present study, 1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol (PLAG) inhibited tumor overgrowth by suppressing excessive neutrophil infiltration, resulting in >74.97 % reduction in tumor size in a Lewis lung carcinoma (LLC-1) mouse model. All subjects in the positive control group died during the 90-day survival period, whereas only four subjects in the PLAG treatment group survived. PLAG had a significantly higher tumor growth inhibitory effect and survival rate than other neutrophil infiltration-targeting inhibitors (e.g., Navarixin, lymphocyte antigen 6 complex locus G6D antibody [aLy6G]). The ability of PLAG to regulate neutrophil infiltration and inhibit tumor growth depends on thioredoxin-interacting protein (TXNIP). In tumors lacking TXNIP expression, PLAG failed to control neutrophil infiltration and infiltration-related factor release, and the inhibitory effect of PLAG on tumor growth was reduced. PLAG-mediated inhibition of neutrophil infiltration enhances the efficacy of immune checkpoint inhibitors (ICIs), increasing the antitumor efficacy and survival rate by 30 %. In conclusion, PLAG could be a novel alternative to anti-tumor drugs that effectively targets excessive neutrophil infiltration into cancer tissues.


Subject(s)
Carcinoma, Lewis Lung , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Mice, Inbred C57BL , Neutrophil Infiltration , Tumor Microenvironment , Animals , Lung Neoplasms/drug therapy , Lung Neoplasms/pathology , Lung Neoplasms/immunology , Carcinoma, Lewis Lung/drug therapy , Carcinoma, Lewis Lung/pathology , Carcinoma, Lewis Lung/immunology , Mice , Neutrophil Infiltration/drug effects , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/pathology , Carcinoma, Non-Small-Cell Lung/immunology , Tumor Microenvironment/drug effects , Diglycerides/pharmacology , Cell Line, Tumor , Neutrophils/drug effects , Neutrophils/immunology , Neutrophils/metabolism , Disease Models, Animal , Male , Antineoplastic Agents/pharmacology , Glycerides
11.
Blood ; 118(20): 5476-86, 2011 Nov 17.
Article in English | MEDLINE | ID: mdl-21960590

ABSTRACT

Perforin (Prf1) and granzyme B (GzmB) are essential effector molecules for natural killer (NK)-cell cytotoxicity, but how Prf1 and GzmB expression is regulated during arming of NK cells is poorly defined. We show that human microRNA (miR)-27a* is a negative regulator of NK-cell cytotoxicity by silencing Prf1 and GzmB expression. Human miR-27a* specifically bound to the 3' untranslated regions of Prf1 and GzmB, down-regulating expression in both resting and activated NK cells, and it functioned as a fine-tuner for homeostasis of the net amount of the effector proteins. Consistent with miR-27a* having an inhibitory role, knockdown of miR-27a* in NK cells dramatically increased cytotoxicity in vitro and decreased tumor growth in a human tumor xenograft model. Thus, NK-cell cytotoxicity is regulated, in part, by microRNA, and modulating endogenous miR-27a* levels in NK cells represents a potential immunotherapeutic strategy.


Subject(s)
Colonic Neoplasms/immunology , Granzymes/genetics , Killer Cells, Natural/physiology , MicroRNAs/physiology , Pore Forming Cytotoxic Proteins/genetics , 3' Untranslated Regions/genetics , Animals , Cell Line, Transformed , Cell Line, Tumor , Cells, Cultured , Colonic Neoplasms/therapy , Female , Fetal Blood/cytology , Gene Silencing , Genetic Therapy/methods , Humans , Killer Cells, Natural/cytology , Mice , Mice, Inbred BALB C , Mice, Nude , MicroRNAs/genetics , MicroRNAs/pharmacology , Perforin , Xenograft Model Antitumor Assays
12.
J Biol Chem ; 286(14): 12450-60, 2011 Apr 08.
Article in English | MEDLINE | ID: mdl-21247902

ABSTRACT

Considerable attention has recently been paid to the N-Myc downstream-regulated gene (NDRG) family because of its potential as a tumor suppressor in many human cancers. Primary amino acid sequence information suggests that the NDRG family proteins may belong to the α/ß-hydrolase (ABH) superfamily; however, their functional role has not yet been determined. Here, we present the crystal structures of the human and mouse NDRG2 proteins determined at 2.0 and 1.7 Å resolution, respectively. Both NDRG2 proteins show remarkable structural similarity to the ABH superfamily, despite limited sequence similarity. Structural analysis suggests that NDRG2 is a nonenzymatic member of the ABH superfamily, because it lacks the catalytic signature residues and has an occluded substrate-binding site. Several conserved structural features suggest NDRG may be involved in molecular interactions. Mutagenesis data based on the structural analysis support a crucial role for helix α6 in the suppression of TCF/ß-catenin signaling in the tumorigenesis of human colorectal cancer, via a molecular interaction.


Subject(s)
Crystallography, X-Ray/methods , Tumor Suppressor Proteins/chemistry , Tumor Suppressor Proteins/metabolism , Amino Acid Sequence , Cell Differentiation/genetics , Cell Differentiation/physiology , Cell Line, Tumor , HEK293 Cells , Humans , Immunoprecipitation , Molecular Sequence Data , Protein Structure, Secondary , Reverse Transcriptase Polymerase Chain Reaction , Sequence Homology, Amino Acid
13.
Tumour Biol ; 33(3): 731-8, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22373580

ABSTRACT

KLK6 encoding kallikrein-related peptidase 6, a trypsin-like serine protease, has been shown to be upregulated in several cancers, although the tumorigenic role of KLK6 has not been elucidated. In this study, KLK6 was identified as a highly upregulated gene in gastric cancer; therefore, the possibility that KLK6 might be a suitable candidate tumor marker was examined. RT-PCR and immunohistochemical analysis showed overexpression of KLK6 in gastric cancer tissues compared to nontumor regions. Sera from gastric cancer patients had a 1.7-fold increase in KLK6 (373.1 µg/L, P = 0.048) compared to healthy individuals (214.2 µg/L), although there was no significant difference among patients with various tumor stages. Cellular invasiveness decreased by 45% in cells transfected with KLK6-specific small interfering RNA. Exogenous overexpression of KLK6 led to decreased activity of the E-cadherin promoter. This study shows that KLK6 is significantly upregulated and secreted in gastric cancer tissues and sera, suggesting that KLK6 might be used as a potential biomarker and therapeutic target for gastric cancer.


Subject(s)
Gene Expression Regulation, Neoplastic , Kallikreins/genetics , Kallikreins/metabolism , Stomach Neoplasms/enzymology , Stomach Neoplasms/genetics , Cadherins/genetics , Cell Line, Tumor , Humans , Neoplasm Invasiveness/genetics , Promoter Regions, Genetic , RNA, Messenger/metabolism , Transcriptional Activation , Up-Regulation/genetics
14.
Bioorg Med Chem Lett ; 22(6): 2318-20, 2012 Mar 15.
Article in English | MEDLINE | ID: mdl-22361132

ABSTRACT

Bioactivity-guided fractionation on the leaves of Aleurites fordii led to the isolation of a new tigliane diterpene ester, 12-O-hexadecanoyl-7-oxo-5-ene-16-hydroxyphorbol-13-acetate (1) along with four known compounds, 12-O-hexadecanoyl-7-oxo-5-ene-phorbol-13-acetate (2), 12-O-hexadecanoyl-phorbol-13-acetate (3), 12-O-hexadecanoyl-16-hydroxyphorbol-13-acetate (4), and 12-O-hexadecanoyl-4-deoxy-4α-16-hydroxyphorbol-13-acetate (5). The structures of these compounds were determined by interpretation of NMR (1D and 2D) spectroscopic data and MS data. All the isolates were evaluated for their effects on the induction of IFN-γ in NK92 cells. Compounds 3 and 4 exhibited the most potent responses in IFN-γ induction, comparable to the positive control, phorbol 12-myristate 13-acetate (PMA).


Subject(s)
Aleurites/chemistry , Antiviral Agents/chemistry , Diterpenes/chemistry , Plant Leaves/chemistry , Antiviral Agents/isolation & purification , Antiviral Agents/pharmacology , Cell Line , Diterpenes/isolation & purification , Diterpenes/pharmacology , Esters , Interferon-gamma/biosynthesis , Killer Cells, Natural/drug effects , Magnetic Resonance Spectroscopy , Mass Spectrometry , Plant Extracts/chemistry , Solid Phase Extraction , Tetradecanoylphorbol Acetate/pharmacology
15.
Neoplasia ; 31: 100815, 2022 09.
Article in English | MEDLINE | ID: mdl-35728512

ABSTRACT

Extracellular adenosine in the tumor microenvironment plays a vital role in cancer development. Specifically, activation of adenosine receptors affects tumor cell growth and adenosine release. We examined the anti-tumor efficacy of 1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol (PLAG) in animal models, revealing the role of PLAG in inhibiting tumor progression by promoting the degradation of adenosine 2B receptors (A2BRs) in tumors. PLAG induced the expression of thioredoxin-interacting protein (TXNIP), a type of α-arrestin that accelerates A2BR internalization by interacting with A2BR complexes containing ß-arrestin. Engulfed receptors bound to TXNIP were rapidly degraded after E3 ligase recruitment and ubiquitination, resulting in early termination of intracellular signals that promote tumor overgrowth. However, in control cancer cells, A2BRs bound to protein phosphatase 2A and were returned to the cell membrane instead of being degraded, resulting in continuous receptor-mediated signaling by pathways including the Raf-Erk axis, which promotes tumor proliferation. A TXNIP-silenced cell-implanted mouse model and TXNIP knockout (KO) mice were used to verify that PLAG-mediated suppression of tumor progression is dependent on TXNIP expression. Increased tumor growth was observed in TXNIP-silenced cell-implanted mice, and the anti-tumor effects of PLAG, including delayed tumor overgrowth, were greatly reduced. However, the anti-tumor effects of PLAG were observed in cancer cell-implanted TXNIP-KO mice, which indicates that PLAG produces anti-tumor effects by enhancing TXNIP expression in tumor cells. These essential functions of PLAG, including delaying tumor growth via A2BR degradation, suggest innovative directions for anticancer drug development.


Subject(s)
Carcinoma, Lewis Lung , Carcinoma, Non-Small-Cell Lung , Carrier Proteins , Lung Neoplasms , Receptors, Purinergic P1 , Thioredoxins , Adenosine/pharmacology , Animals , Carcinoma, Lewis Lung/drug therapy , Carcinoma, Lewis Lung/metabolism , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/metabolism , Carrier Proteins/metabolism , Diglycerides/metabolism , Diglycerides/pharmacology , Mice , Receptors, Purinergic P1/drug effects , Receptors, Purinergic P1/metabolism , Thioredoxins/metabolism , Tumor Microenvironment
16.
Transl Oncol ; 20: 101398, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35339890

ABSTRACT

Chemotherapy-induced cachexia has been a significant challenge to the successful treatment of cancer patients. Chemotherapy leads to loss of muscle, loss of appetite, and excessive weight loss, which makes these necessary treatments intolerable for most patients. Therefore, it is necessary to alleviate cachexia to successfully treat cancer patients. In this study, tumor-implanted mouse models administered cisplatin showed rapid weight loss and reduced feeding rate by the second week of treatment, and 1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol (PLAG) effectively alleviated cisplatin-induced cachexia. In mice treated with cisplatin on a sacrificial day after 6 weeks, the weight of the two major leg muscles (quadriceps femoris and gastrocnemius) were reduced by up to 70%, but this muscle reduction was successfully prevented in the PLAG co-treatment group. The distribution and size of muscle fibers that appear in small units in cisplatin-treated mice were restored to normal levels by PLAG co-treatment. Furthermore, myostatin expression levels were upregulated by cisplatin, whereas myostatin decreased to normal levels with muscle recovery in the PLAG co-treated group. Tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6), which are commonly expressed in cachexia, were significantly increased in cisplatin-treated mice but were reduced to normal levels in PLAG co-treated mice. Glucose absorption, an indicator of muscle tissue activity, decreased with cisplatin treatment and recovered to normal levels with PLAG co-treatment. Overall, PLAG effectively alleviated cisplatin-induced cachexia symptoms and reduced tumor growth in tumor-implanted mice. These findings suggest PLAG may be a promising drug to alleviate cachexia in cancer patients receiving chemotherapy.

17.
Cancer ; 117(12): 2608-19, 2011 Jun 15.
Article in English | MEDLINE | ID: mdl-21656738

ABSTRACT

BACKGROUND: Kallikrein-related peptidase 6 (KLK6) encodes a trypsin-like serine protease that is up-regulated in several cancers, although the putative functions of KLK6 in cancer have not been elucidated. In the current study, overexpression of KLK6 was identified in colon cancer, and the possibility that KLK6 may be a suitable candidate as a tumor marker was examined. METHODS: Messenger RNA (mRNA) transcript levels and protein up-regulation of KLK6 in colon cancer tissues was examined using reverse transcriptase-polymerase chain reaction, immunohistochemistry, and clinicopathologic analyses. Cell proliferation, invasiveness, and antiapoptotic activity were determined in colon cancer cells that were transfected with small-interfering RNA (siRNA) of KLK6. RESULTS: KLK6 mRNA was up-regulated significantly in tumor tissues compared with nontumor regions. KLK6 protein was strongly expressed in adenocarcinomas but was not expressed in normal mucosa or in premalignant dysplastic lesions. Sera from patients with colon cancer revealed an increase in KLK6 secretion (0.25 µg/mL; P = .031) compared with noncancer cells (0.19 µg/mL). Clinicopathologic and immunohistochemical studies of 143 patients with colon cancer revealed a significant correlation between KLK6 expression and Dukes disease stage (P = .005). High KLK6 expression was associated significantly with shorter overall (P = .001) and recurrence-free survival (P = .001). The rates of proliferation and invasiveness were decreased by 50% in cells that were transfected with KLK6 siRNA. The overexpression of KLK6 led to decreased activity of the E-cadherin promoter. CONCLUSIONS: KLK6 was up-regulated significantly in tissues and sera from patients with colon cancer and was associated closely with a poor prognosis, suggesting that KLK6 may be used as a potential biomarker and a therapeutic target for colon cancer.


Subject(s)
Colonic Neoplasms/enzymology , Kallikreins/physiology , Adult , Aged , Cell Line, Tumor , Colon/enzymology , Colonic Neoplasms/mortality , Colonic Neoplasms/pathology , Female , Humans , Kallikreins/analysis , Kallikreins/genetics , Male , Middle Aged , Neoplasm Invasiveness , Neoplasm Staging , Prognosis , Proportional Hazards Models , RNA, Messenger/analysis , Up-Regulation
18.
PLoS Pathog ; 5(8): e1000561, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19714221

ABSTRACT

Pseudomonas aeruginosa (PA) is an opportunistic pathogen that causes the relapse of illness in immunocompromised patients, leading to prolonged hospitalization, increased medical expense, and death. In this report, we show that PA invades natural killer (NK) cells and induces phagocytosis-induced cell death (PICD) of lymphocytes. In vivo tumor metastasis was augmented by PA infection, with a significant reduction in NK cell number. Adoptive transfer of NK cells mitigated PA-induced metastasis. Internalization of PA into NK cells was observed by transmission electron microscopy. In addition, PA invaded NK cells via phosphoinositide 3-kinase (PI3K) activation, and the phagocytic event led to caspase 9-dependent apoptosis of NK cells. PA-mediated NK cell apoptosis was dependent on activation of mitogen-activated protein (MAP) kinase and the generation of reactive oxygen species (ROS). These data suggest that the phagocytosis of PA by NK cells is a critical event that affects the relapse of diseases in immunocompromised patients, such as those with cancer, and provides important insights into the interactions between PA and NK cells.


Subject(s)
Apoptosis/immunology , Killer Cells, Natural/immunology , Phagocytosis/immunology , Pseudomonas aeruginosa/immunology , Animals , Caspase 9/immunology , Caspase 9/metabolism , Cell Line, Tumor , Cell Survival/physiology , Flow Cytometry , Humans , Immunohistochemistry , Killer Cells, Natural/metabolism , Killer Cells, Natural/microbiology , Melanoma/immunology , Melanoma/microbiology , Mice , Mice, Inbred C57BL , Microscopy, Electron, Transmission , Neoplasm Metastasis , Neoplasm Transplantation , Phosphatidylinositol 3-Kinases/metabolism , Reactive Oxygen Species/metabolism
19.
Amino Acids ; 40(3): 1003-13, 2011 Mar.
Article in English | MEDLINE | ID: mdl-20821239

ABSTRACT

Endothelial cell-specific molecule-1 (ESM-1) is a secretory proteoglycan comprising a mature polypeptide of 165 amino acids and a single dermatan sulfate. The aim of this study was to evaluate endothelial cell-specific molecule-1 (ESM-1) as a hepatocellular carcinoma (HCC) marker and to analyze the effect of ESM-1 gene silencing in hepatocellular carcinoma cells. RT-PCR and Western Blot analysis revealed overexpression of ESM-1 in human HCC liver tissue and in serum from patients with HCC. Sandwich ELISA assay was used for quantitative analysis of ESM-1 in serum. Levels of ESM-1 were significantly elevated in the serum of patients with HCC (n = 40) as compared to serum from patients with hepatitis (AH, n = 40; CH, n = 39) or liver cirrhosis (n = 40) or from healthy subjects (n = 40). The accuracy of ESM-1 for HCC was higher than that of α-fetoprotein (AFP) according to ROC curve analysis. Expression of ESM-1 siRNA decreased cell survival through the inhibition of NF-κB pathway and induced cell cycle arrest by PTEN induction resulting in the inhibition of cyclin D1 in SK-Hep1 cells. Furthermore, ESM-1 silencing inhibited cell migration and invasion of SK-Hep1 cells. This study demonstrates that ESM-1 as a potential tumor marker is overexpressed in most tissues and serum in the presence of HCC and is involved with cell survival, cell cycle progression, migration, and invasion of hepatocellular carcinoma cells. Based on our results, we suggest that ESM-1 or a combination of ESM-1 and AFP is useful markers for diagnosis of HCC and ESM-1 may be useful therapeutic target of hepatocellular carcinoma.


Subject(s)
Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/physiopathology , Cell Cycle , Gene Silencing , Liver Neoplasms/genetics , Liver Neoplasms/physiopathology , Neoplasm Invasiveness , Neoplasm Proteins/genetics , Proteoglycans/genetics , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Cell Movement , Cell Survival , Humans , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Neoplasm Proteins/metabolism , Proteoglycans/metabolism , RNA, Small Interfering/genetics , RNA, Small Interfering/metabolism
20.
Skeletal Radiol ; 40(8): 1047-55, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21384198

ABSTRACT

OBJECTIVE: To investigate the usefulness of the external rotation (ER) position on magnetic resonance (MR) arthrography for the diagnosis of superior labral anterior to posterior (SLAP) lesion. MATERIALS AND METHODS: Approval of institutional review board was obtained, and informed consent was waived. The MR arthrograms of 210 shoulders that were arthroscopically confirmed as SLAP lesion in 163 shoulders and intact superior labrum in 47 shoulders were retrospectively reviewed in each neutral and ER position for the diagnosis of SLAP lesion, the extent of distraction of the torn labrum, and the external rotation angle. The sensitivity, specificity, and diagnostic accuracy of MR arthrograms for determining SLAP lesion were assessed in each position. For the arthroscopically confirmed group, the diagnosis of SLAP lesion and the extent of distraction about the tear were compared between neutral and ER positions by Fisher's exact test and the paired t-test. The correlation between the external rotation angle and the diagnosis of SLAP lesion, and between the external rotation angle and the differences in the extent of distraction were evaluated in the ER position using the ANOVA test. RESULTS: Sensitivity and diagnostic accuracy of MR arthrography for SLAP lesion increased from 64.4% and 71.0% in the neutral position to 78.5% and 81.9% in the ER position, respectively, without change of specificity, which was 93.6% in both positions. The diagnosis of SLAP lesion was changed from negative to SLAP lesion in 16.0% of the arthroscopically confirmed group. Mean difference in the extent of distraction about the tear was 0.69 mm (range -1.40 ∼ 6.67 mm), which was statistically significant. There was no relationship between the external rotation angle and the diagnosis of SLAP lesion, and between the external rotation angle and the differences in the extent of distraction. CONCLUSION: Shoulder MR arthrography with additional ER positioning helps in the diagnosis of SLAP lesion and provides information about the displaceability of the torn labrum.


Subject(s)
Magnetic Resonance Imaging/methods , Shoulder Injuries , Adolescent , Adult , Aged , Analysis of Variance , Arthroscopy , Contrast Media , Female , Humans , Image Interpretation, Computer-Assisted , Male , Meglumine , Middle Aged , Organometallic Compounds , Patient Positioning , Rotation , Sensitivity and Specificity , Shoulder Joint/pathology
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