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1.
Int J Mol Sci ; 22(20)2021 Oct 19.
Article in English | MEDLINE | ID: mdl-34681918

ABSTRACT

The phosphoinositide-3-kinase (PI3K) pathway has widely been considered as a potential therapeutic target for head and neck cancer (HNC); however, the application of PI3K inhibitors is often overshadowed by the induction of drug resistance with unknown mechanisms. In this study, PII3K inhibitor resistant cancer cells were developed by prolonged culturing of cell lines with BEZ235, a dual PI3K and mammalian target of rapamycin (mTOR) inhibitor. The drug resistant HNC cells showed higher IC50 of the proliferation to inhibitors specifically targeting PI3K and/or mTOR, as compared to their parental cells. These cells also showed profound resistance to drugs of other classes. Molecular analysis revealed persistent activation of phosphorylated AKT at threonine 308 in the drug resistant cells and increased expression of markers for tumor-initiating cells. Interestingly, increased intra-cellular ROS levels were observed in the drug resistant cells. Among anti-oxidant molecules, the expression of SOD2 was increased and was associated with the ALDH-positive tumor-initiating cell features. Co-incubation of SOD inhibitors and BEZ235 decreased the stemness feature of the cells in vitro, as shown by results of the spheroid formation assay. In conclusion, dysregulation of SOD2 might contribute to the profound resistance to PI3K inhibitors and the other drugs in HNC cells.


Subject(s)
Drug Resistance, Neoplasm , Head and Neck Neoplasms/metabolism , Imidazoles/pharmacology , Neoplastic Stem Cells/drug effects , Proto-Oncogene Proteins c-akt/metabolism , Quinolines/pharmacology , Superoxide Dismutase/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Resistance, Multiple , Gene Expression Regulation, Neoplastic/drug effects , Head and Neck Neoplasms/drug therapy , Humans , Neoplastic Stem Cells/metabolism , Phosphatidylinositol 3-Kinase/metabolism , Phosphorylation , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects , Up-Regulation
2.
J Rehabil Med ; 53(1): jrm00144, 2021 Jan 13.
Article in English | MEDLINE | ID: mdl-33367924

ABSTRACT

OBJECTIVE: To assess the dose-related effects of radial extracorporeal shock wave therapy on pain alleviation in knee osteoarthritis. METHODS: With the use of a 2?×?2 factorial randomized controlled design, 89 patients diagnosed with knee osteoarthritis were assigned to 1 of 4 treatment groups, which varied in terms of shock intensity (0.12 mJ/mm2, lower density, or 0.24 mJ/mm2, higher density) and shock number (2,000 impulses or 4,000 impulses), or to a placebo control. Each group received 4 sessions of radial extracorporeal shock wave therapy, one week apart. The primary outcome was pain intensity measured on a visual analogue scale, and the secondary outcome was the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score. Assessments were performed at baseline, after each session, and at 4-week follow-up. RESULTS: Two-way repeated-measures analysis of variance revealed a significant effect on the Pain score for intensity (p<0.001), with no effect for number (p=0.467) or the intensity?number interaction (p=0.536). Similar results were obtained for the WOMAC scores, except for an association between number and WOMAC score (p=0.036). At the 4-week follow-up, all treatment groups showed greater reductions in the Pain and WOMAC scores than the control group. In addition, scores decreased more at higher densities of shock intensity than at lower densities, while there was no significant difference between the 2,000- and 4,000-shock conditions. CONCLUSION: Moderate-intensity radial extracorporeal shock wave therapy was effective, and a higher density might be more efficacious in alleviating pain in knee osteoarthritis.


Subject(s)
Extracorporeal Shockwave Therapy/adverse effects , Osteoarthritis, Knee/therapy , Double-Blind Method , Extracorporeal Shockwave Therapy/methods , Female , Humans , Male , Middle Aged , Treatment Outcome
3.
J Biomed Sci ; 26(1): 77, 2019 Oct 19.
Article in English | MEDLINE | ID: mdl-31629402

ABSTRACT

BACKGROUND: Intratumor subsets with tumor-initiating features in glioblastoma are likely to survive treatment. Our goal is to identify the key factor in the process by which cells develop temozolomide (TMZ) resistance. METHODS: Resistant cell lines derived from U87MG and A172 were established through long-term co-incubation of TMZ. Primary tumors obtained from patients were maintained as patient-derived xenograft for studies of tumor-initating cell (TIC) features. The cell manifestations were assessed in the gene modulated cells for relevance to drug resistance. RESULTS: Among the mitochondria-related genes in the gene expression databases, superoxide dismutase 2 (SOD2) was a significant factor in resistance and patient survival. SOD2 in the resistant cells functionally determined the cell fate by limiting TMZ-stimulated superoxide reaction and cleavage of caspase-3. Genetic inhibition of the protein led to retrieval of drug effect in mouse study. SOD2 was also associated with the TIC features, which enriched in the resistant cells. The CD133+ specific subsets in the resistant cells exhibited superior superoxide regulation and the SOD2-related caspase-3 reaction. Experiments applying SOD2 modulation showed a positive correlation between the TIC features and the protein expression. Finally, co-treatment with TMZ and the SOD inhibitor sodium diethyldithiocarbamate trihydrate in xenograft mouse models with the TMZ-resistant primary tumor resulted in lower tumor proliferation, longer survival, and less CD133, Bmi-1, and SOD2 expression. CONCLUSION: SOD2 plays crucial roles in the tumor-initiating features that are related to TMZ resistance. Inhibition of the protein is a potential therapeutic strategy that can be used to enhance the effects of chemotherapy.


Subject(s)
Antineoplastic Agents, Alkylating/pharmacology , Drug Resistance, Neoplasm/genetics , Glioblastoma/drug therapy , Neoplastic Stem Cells/drug effects , Superoxide Dismutase/administration & dosage , Temozolomide/pharmacology , Animals , Cell Line, Tumor , Gene Expression Regulation, Neoplastic/drug effects , Heterografts/physiopathology , Humans , Mice , Neoplastic Stem Cells/physiology
4.
Redox Biol ; 13: 655-664, 2017 10.
Article in English | MEDLINE | ID: mdl-28822335

ABSTRACT

Acquisition of temozolomide (TMZ) resistance is a major factor leading to the failure of glioblastoma (GBM) treatment. The exact mechanism by which GBM evades TMZ toxicity is not always related to the expression of the DNA repair enzyme O6-methylguanine-DNA methyltransferase (MGMT), and so remains unclear. In this study, TMZ-resistant variants derived from MGMT-negative GBM clinical samples and cell lines were studied, revealing there to be increased specificity protein 1 (Sp1) expression associated with reduced reactive oxygen species (ROS) accumulation following TMZ treatment. Analysis of gene expression databases along with cell studies identified the ROS scavenger superoxide dismutase 2 (SOD2) as being disease-related. SOD2 expression was also increased, and it was found to be co-expressed with Sp1 in TMZ-resistant cells. Investigation of the SOD2 promoter revealed Sp1 as a critical transcriptional activator that enhances SOD2 gene expression. Co-treatment with an Sp1 inhibitor restored the inhibitory effects of TMZ, and decreased SOD2 levels in TMZ-resistant cells. This treatment strategy restored susceptibility to TMZ in xenograft animals, leading to prolonged survival in an orthotopic model. Thus, our results suggest that Sp1 modulates ROS scavengers as a novel mechanism to increase cancer malignancy and resistance to chemotherapy. Inhibition of this pathway may represent a potential therapeutic target for restoring treatment susceptibility in GBM.


Subject(s)
Antineoplastic Agents, Alkylating/pharmacology , Brain Neoplasms/metabolism , Dacarbazine/analogs & derivatives , Drug Resistance, Neoplasm , Glioblastoma/metabolism , Superoxide Dismutase/metabolism , Animals , Antineoplastic Agents, Alkylating/therapeutic use , Brain Neoplasms/drug therapy , Cell Line, Tumor , DNA Modification Methylases/metabolism , DNA Repair Enzymes/metabolism , Dacarbazine/pharmacology , Dacarbazine/therapeutic use , Glioblastoma/drug therapy , Humans , Male , Mice , Mice, Inbred NOD , Mice, SCID , Reactive Oxygen Species/metabolism , Sp1 Transcription Factor/metabolism , Superoxide Dismutase/genetics , Temozolomide , Tumor Suppressor Proteins/metabolism
5.
Oncotarget ; 6(33): 35073-86, 2015 Oct 27.
Article in English | MEDLINE | ID: mdl-26551021

ABSTRACT

Our previous studies suggest that antibodies against ENO1 (anti-ENO1 Ab) have a protective role in patients with non-small cell lung carcinoma. In this study, we evaluated the prognostic value of anti-ENO1 Ab levels in non-small cell lung carcinoma patients undergoing surgery. Circulating levels of anti-ENO1 Ab were assessed in 85 non-small cell lung carcinoma patients before and after surgery, and were correlated with clinical outcome. After surgery, patients with a higher increase of anti-ENO1 Ab had a lower hazard ratio and a better progression-free survival. Using animal models, we demonstrated that tumor cells reduce the circulating levels of anti-ENO1 Ab through physical absorption and neutralization of anti-ENO1 Ab with surface-expressed and secreted ENO1, respectively. Mice transplanted with ENO1-overexpressing tumors generated ENO1-specific regulatory T cells to suppress the production of anti-ENO1 Ab. Our results suggest that the increase of anti-ENO1 Ab may reflect anti-tumor immune responses and serve as a prognostic marker in postoperative lung cancer patients.


Subject(s)
Antibodies, Neoplasm/blood , Biomarkers, Tumor/immunology , Carcinoma, Non-Small-Cell Lung/immunology , DNA-Binding Proteins/immunology , Lung Neoplasms/immunology , Phosphopyruvate Hydratase/immunology , Tumor Suppressor Proteins/immunology , Aged , Animals , Biomarkers, Tumor/analysis , Biomarkers, Tumor/blood , Carcinoma, Non-Small-Cell Lung/blood , Carcinoma, Non-Small-Cell Lung/mortality , Disease-Free Survival , Enzyme-Linked Immunosorbent Assay , Female , Humans , Kaplan-Meier Estimate , Lung Neoplasms/blood , Lung Neoplasms/mortality , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Middle Aged , Prognosis
6.
PLoS One ; 8(7): e69354, 2013.
Article in English | MEDLINE | ID: mdl-23894455

ABSTRACT

In previous research, we found α-enolase to be inversely correlated with progression-free and overall survival in lung cancer patients and detected α-enolase on the surface of lung cancer cells. Based on these findings, we hypothesized that surface α-enolase has a significant role in cancer metastasis and tested this hypothesis in the current study. We found that α-enolase was co-immunoprecipitated with urokinase-type plasminogen activator, urokinase-type plasminogen activator receptor, and plasminogen in lung cancer cells and interacted with these proteins in a cell-free dot blotting assay, which can be interrupted by α-enolase-specific antibody. α-Enolase in lung cancer cells co-localized with these proteins and was present at the site of pericellular degradation of extracellular matrix components. Treatment with antibody against α-enolase in vitro suppressed cell-associated plasminogen and matrix metalloproteinase activation, collagen and gelatin degradation, and cell invasion. Examination of the effect of treatment with shRNA plasmids revealed that down regulation of α-enolase decreases extracellular matrix degradation by and the invasion capacity of lung cancer cells. Adoptive transfer of α-enolase-specific antibody to mice resulted in accumulation of antibody in subcutaneous tumor and inhibited the formation of tumor metastasis in lung and bone. This study demonstrated that surface α-enolase promotes extracellular matrix degradation and invasion of cancer cells and that targeting surface α-enolase is a promising approach to suppress tumor metastasis.


Subject(s)
Cell Membrane/metabolism , Extracellular Matrix/metabolism , Neoplasms/metabolism , Neoplasms/pathology , Phosphopyruvate Hydratase/metabolism , Animals , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/pharmacology , Biomarkers, Tumor/antagonists & inhibitors , Biomarkers, Tumor/metabolism , Bone Neoplasms/drug therapy , Bone Neoplasms/secondary , Cell Line, Tumor , Cell Movement , DNA-Binding Proteins/antagonists & inhibitors , DNA-Binding Proteins/metabolism , Humans , Immunocompromised Host , Lung Neoplasms/metabolism , Lung Neoplasms/mortality , Lung Neoplasms/pathology , Male , Mice , Neoplasm Metastasis , Neoplasms/mortality , Phosphopyruvate Hydratase/antagonists & inhibitors , Plasminogen/metabolism , Protein Binding , Receptors, Urokinase Plasminogen Activator/metabolism , Tumor Suppressor Proteins/antagonists & inhibitors , Tumor Suppressor Proteins/metabolism , Urokinase-Type Plasminogen Activator/metabolism , Xenograft Model Antitumor Assays
7.
J Biomed Sci ; 20: 43, 2013 Jun 27.
Article in English | MEDLINE | ID: mdl-23806066

ABSTRACT

BACKGROUND: Dysregulated epidermal growth factor receptor (EGFR)-phosphoinositide-3-kinase (PI3K)-AKT signaling is considered pivotal for oral cancer, and the pathway is a potential candidate for therapeutic targeting. RESULTS: A total of 108 archival samples which were from surgically resected oral cancer were examined. Immunohistochemical staining showed the protein expression of membranous wild-type EGFR and cytoplasmic phosphorylated AKT was detected in 63.9% and 86.9% of the specimens, respectively. In 49.1% of the samples, no phosphatase and tensin homolog (PTEN) expression was detected. With regard to the EGFR variant III (EGFRvIII), 75.0% of the samples showed positive expression for moderate to severe staining, 31.5% of which had high expression levels. Real-time polymerase chain reaction assays for gene copy number assessment of PIK3CA revealed that 24.8% of the samples had alterations, and of EGFR showed that 49.0% had amplification. Direct sequencing of PIK3CA gene showed 2.3% of the samples had a hotspot point mutation. Statistical assessment showed the expression of the EGFRvIII correlated with the T classification and TNM stage. The Kaplan-Meier analyses for patient survival showed that the individual status of phosphorylated AKT and EGFRvIII led to significant differences in survival outcome. The multivariate analysis indicated that phosphorylated AKT, EGFRvIII expression and disease stage were patient survival determinants. CONCLUSIONS: Aberrations in the EGFR-PI3K-AKT pathway were frequently found in oral cancers. EGFRvIII and phosphorylated AKT were predictors for the patient survival and clinical outcome.


Subject(s)
ErbB Receptors/metabolism , Mouth Neoplasms/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Adult , Aged , ErbB Receptors/genetics , Female , Humans , Male , Middle Aged , Mouth Neoplasms/genetics , Mutation , Phosphatidylinositol 3-Kinases/genetics , Phosphorylation , Proto-Oncogene Proteins c-akt/genetics , Signal Transduction
8.
J Biol Chem ; 285(5): 3245-52, 2010 Jan 29.
Article in English | MEDLINE | ID: mdl-19948735

ABSTRACT

Tubulointerstitial nephritis is a cardinal renal manifestation of leptospirosis. LipL32, a major lipoprotein and a virulence factor, locates on the outer membrane of the pathogen Leptospira. It evades immune response by recognizing and adhering to extracellular matrix components of the host cell. The crystal structure of Ca(2+)-bound LipL32 was determined at 2.3 A resolution. LipL32 has a novel polyD sequence of seven aspartates that forms a continuous acidic surface patch for Ca(2+) binding. A significant conformational change was observed for the Ca(2+)-bound form of LipL32. Calcium binding to LipL32 was determined by isothermal titration calorimetry. The binding of fibronectin to LipL32 was observed by Stains-all CD and enzyme-linked immunosorbent assay experiments. The interaction between LipL32 and fibronectin might be associated with Ca(2+) binding. Based on the crystal structure of Ca(2+)-bound LipL32 and the Stains-all results, fibronectin probably binds near the polyD region on LipL32. Ca(2+) binding to LipL32 might be important for Leptospira to interact with the extracellular matrix of the host cell.


Subject(s)
Bacterial Outer Membrane Proteins/physiology , Calcium/chemistry , Fibronectins/chemistry , Leptospira/metabolism , Lipoproteins/physiology , Amino Acid Sequence , Bacterial Outer Membrane Proteins/chemistry , Calorimetry/methods , Circular Dichroism/methods , Crystallography, X-Ray/methods , Enzyme-Linked Immunosorbent Assay , Lipoproteins/chemistry , Molecular Sequence Data , Protein Binding , Protein Structure, Secondary , Surface Properties
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