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1.
Entropy (Basel) ; 24(11)2022 Nov 13.
Article in English | MEDLINE | ID: mdl-36421501

ABSTRACT

Data representation has been one of the core topics in 3D graphics and pattern recognition in high-dimensional data. Although the high-resolution geometrical information of a physical object can be well preserved in the form of metrical data, e.g., point clouds/triangular meshes, from a regular data (e.g., image/audio) processing perspective, they also bring excessive noise in the course of feature abstraction and regression. For 3D face recognition, preceding attempts focus on treating the scan samples as signals laying on an underlying discrete surface (mesh) or morphable (statistic) models and by embedding auxiliary information, e.g., texture onto the regularized local planar structure to obtain a superior expressive performance to registration-based methods, but environmental variations such as posture/illumination will dissatisfy the integrity or uniform sampling condition, which holistic models generally rely on. In this paper, a geometric deep learning framework for face recognition is proposed, which merely requires the consumption of raw spatial coordinates. The non-uniformity and non-grid geometric transformations in the course of point cloud face scanning are mitigated by modeling each identity as a stochastic process. Individual face scans are considered realizations, yielding underlying inherent distributions under the appropriate assumption of ergodicity. To accomplish 3D facial recognition, we propose a windowed solid harmonic scattering transform on point cloud face scans to extract the invariant coefficients so that unrelated variations can be encoded into certain components of the scattering domain. With these constructions, a sparse learning network as the semi-supervised classification backbone network can work on reducing intraclass variability. Our framework obtained superior performance to current competing methods; without excluding any fragmentary or severely deformed samples, the rank-1 recognition rate (RR1) achieved was 99.84% on the Face Recognition Grand Challenge (FRGC) v2.0 dataset and 99.90% on the Bosphorus dataset.

2.
J Biomed Sci ; 29(1): 29, 2022 May 09.
Article in English | MEDLINE | ID: mdl-35534851

ABSTRACT

BACKGROUND: Castration-resistant prostate cancer (CRPC) with sustained androgen receptor (AR) signaling remains a critical clinical challenge, despite androgen depletion therapy. The Jumonji C-containing histone lysine demethylase family 4 (KDM4) members, KDM4A‒KDM4C, serve as critical coactivators of AR to promote tumor growth in prostate cancer and are candidate therapeutic targets to overcome AR mutations/alterations-mediated resistance in CRPC. METHODS: In this study, using a structure-based approach, we identified a natural product, myricetin, able to block the demethylation of histone 3 lysine 9 trimethylation by KDM4 members and evaluated its effects on CRPC. A structure-based screening was employed to search for a natural product that inhibited KDM4B. Inhibition kinetics of myricetin was determined. The cytotoxic effect of myricetin on various prostate cancer cells was evaluated. The combined effect of myricetin with enzalutamide, a second-generation AR inhibitor toward C4-2B, a CRPC cell line, was assessed. To improve bioavailability, myricetin encapsulated by poly lactic-co-glycolic acid (PLGA), the US food and drug administration (FDA)-approved material as drug carriers, was synthesized and its antitumor activity alone or with enzalutamide was evaluated using in vivo C4-2B xenografts. RESULTS: Myricetin was identified as a potent α-ketoglutarate-type inhibitor that blocks the demethylation activity by KDM4s and significantly reduced the proliferation of both androgen-dependent (LNCaP) and androgen-independent CRPC (CWR22Rv1 and C4-2B). A synergistic cytotoxic effect toward C4-2B was detected for the combination of myricetin and enzalutamide. PLGA-myricetin, enzalutamide, and the combined treatment showed significantly greater antitumor activity than that of the control group in the C4-2B xenograft model. Tumor growth was significantly lower for the combination treatment than for enzalutamide or myricetin treatment alone. CONCLUSIONS: These results suggest that myricetin is a pan-KDM4 inhibitor and exhibited potent cell cytotoxicity toward CRPC cells. Importantly, the combination of PLGA-encapsulated myricetin with enzalutamide is potentially effective for CRPC.


Subject(s)
Antineoplastic Agents , Biological Products , Flavonoids , Prostatic Neoplasms, Castration-Resistant , Androgens/pharmacology , Androgens/therapeutic use , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Biological Products/pharmacology , Biological Products/therapeutic use , Cell Line, Tumor , Cell Proliferation , Drug Resistance, Neoplasm , Flavonoids/pharmacology , Glycolates , Glycols/pharmacology , Glycols/therapeutic use , Humans , Jumonji Domain-Containing Histone Demethylases/genetics , Jumonji Domain-Containing Histone Demethylases/pharmacology , Male , Nitriles/pharmacology , Nitriles/therapeutic use , Prostatic Neoplasms, Castration-Resistant/drug therapy , Prostatic Neoplasms, Castration-Resistant/genetics , Prostatic Neoplasms, Castration-Resistant/metabolism , Receptors, Androgen/genetics , Receptors, Androgen/metabolism , Receptors, Androgen/therapeutic use
3.
Biochem Biophys Res Commun ; 527(1): 283-288, 2020 06 18.
Article in English | MEDLINE | ID: mdl-32446381

ABSTRACT

Lysyl oxidase (LOX) is involved in fibrosis by catalyzing collagen cross-linking. Previous work observed that Triptolide (TPL) alleviated radiation-induced pulmonary fibrosis (RIPF), but it is unknown whether the anti-RIPF effect of TPL is related to LOX. In a mouse model of RIPF, we found that LOX persistently increased in RIPF which was significantly lowered by TPL. Excessive LOX aggravated fibrotic lesions in RIPF, while LOX inhibition mitigated RIPF. Irradiation enhanced the transcription and synthesis of LOX by lung fibroblasts through IKKß/NFκB activation, and siRNA knockdown IKKß largely abolished LOX production. By interfering radiation induced IKKß activation, TPL prevented NFκB nuclear translocation and DNA binding, and potently decreased LOX synthesis. Our results demonstrate that the anti-RIPF effect of TPL is associated with reduction of LOX production which mediated by inhibition of IKKß/NFκB pathway.


Subject(s)
Diterpenes/pharmacology , Extracellular Matrix Proteins/antagonists & inhibitors , I-kappa B Kinase/antagonists & inhibitors , Phenanthrenes/pharmacology , Protein-Lysine 6-Oxidase/antagonists & inhibitors , Pulmonary Fibrosis/drug therapy , Radiation Injuries/drug therapy , Animals , Diterpenes/administration & dosage , Dose-Response Relationship, Drug , Epoxy Compounds/administration & dosage , Epoxy Compounds/pharmacology , Extracellular Matrix Proteins/biosynthesis , Female , I-kappa B Kinase/metabolism , Injections, Intravenous , Mice , Mice, Inbred C57BL , Molecular Structure , Phenanthrenes/administration & dosage , Protein-Lysine 6-Oxidase/biosynthesis , Pulmonary Fibrosis/metabolism , Radiation Injuries/metabolism , Structure-Activity Relationship
4.
Langmuir ; 34(4): 1441-1446, 2018 01 30.
Article in English | MEDLINE | ID: mdl-29307176

ABSTRACT

The adsorption of methyl red (MR) isomers (ortho, meta, and para) on metal-organic frameworks (MOFs) was investigated by using a fluorescence quenching technique. All three MR isomers were found to quench the fluorescence of MOFs effectively. Nonlinear fluorescence quenching trends were observed in Stern-Volmer plots. A modified nonlinear Stern-Volmer equation with the concepts of multiple adsorption sites, adsorption strength, and quencher accessibility was successfully adopted to fit the fluorescence quenching data. The fitted parameters were correlated with the structural properties of MRs and MOFs. The order of quenching efficiency was found to be m-MR > p-MR > o-MR for all MOFs. This indicates that MR molecules not only adsorb via carboxylate-metal bonding but also adsorb through π-π interactions between the aromatic rings of MR and linker molecules in MOFs. The position of the carboxylate group in MRs and the structure of the linkers in MOFs are the key factors affecting the fluorescence quenching efficiency.

5.
Int J Radiat Biol ; 93(12): 1334-1342, 2017 12.
Article in English | MEDLINE | ID: mdl-29063809

ABSTRACT

PURPOSE: To investigate the late effects of thoracic region irradiation (TRI) on mouse body weight. MATERIALS AND METHODS: Female C57BL/6 mice were divided into nonirradiated, 5 Gy total body irradiation, 9 Gy sub-total body irradiation, and 12.5 Gy thoracic region irradiation (TRI) groups. Changes in mouse weight were monitored every other week at similar time points for 12 months. The anatomical characteristics of abdominal visceral fat distribution were recorded, and mitochondrial DNA copy number in the hearts and livers and lipid metabolic signaling in the liver were analyzed. Data were analyzed by one-way analysis of variance and a student's t-test. RESULTS: TRI led to a significant increase (p < .001) in body weight that was dependent on time and individuals [42.1% of mice were overweight (50% increase in body weight) 4 months post-TRI and 100% of mice were overweight at 10 months post-TRI]. Gross anatomical features of abdominal visceral fat distribution and storage in radiation-induced overweight/severely overweight mice were similar to those of high fat diet-induced overweight/severely overweight mice. The mitochondrial genome of heart and liver tissues from overweight/severely overweight mice had significantly (p < .05) decreased functional mitochondrial DNA copy number (ratios decreased from 1 to 0.71 or 0.49, respectively) and significantly (p < .05) increased mitochondrial DNA mutations (ratios increased from 1 to 3.21 or 1.83, respectively). CPT1 and IRS2 lipid metabolic signaling was significantly (p < .05-.01) decreased for both mRNA (fold decrease from 1 to 0.60 or 0.55, respectively) and protein (fold decrease from 1 to 0.62 or 0.19, respectively). CONCLUSIONS: TRI can cause mice to gain weight. These findings indicate that TRI can result in lipid metabolic abnormalities and provide a model to study the factors that result in these abnormalities.


Subject(s)
Gamma Rays/adverse effects , Obesity/etiology , Thorax/radiation effects , Animals , Body Weight/radiation effects , Disease Progression , Female , Genome, Mitochondrial/radiation effects , Lipid Metabolism/radiation effects , Mice , Mice, Inbred C57BL , Obesity/genetics , Obesity/metabolism , Obesity/physiopathology
6.
Mol Immunol ; 87: 308-316, 2017 07.
Article in English | MEDLINE | ID: mdl-28531815

ABSTRACT

The use of cytokines as adjuvants in poultry is promising because they may enhance immune responses to antigens. In this study, we created two mutants, chicken interleukin-1 beta (ChIL-1ß) Q19A and R140A, which exhibited significantly increased in vivo biological activity compared with wild-type ChIL-1ß. The potential mucosal adjuvant activity of the mutants Q19A and R140A was evaluated in chickens through the intranasal coadministration of a single dose of the Newcastle disease virus (NDV) vaccine with Q19A or R140A. Compared with chickens vaccinated with only the NDV vaccine or the NDV vaccine plus wild-type recombinant ChIL-1ß, chickens vaccinated with Q19A or R140A had significantly increased serum hemagglutination-inhibition antibody titers and anti-NDV-specific IgA antibody levels 1 week later, a high amount of interferon-γ secretion from splenocytes, and increased secretory IgA accumulated in nasal tissues. In addition, molecular dynamics simulations of the mutant R140A bound to its receptor (IL-1RI) and receptor accessory protein (IL-1RAcP) were more energetically favorable than the analogous wild-type ternary complex resulting in a decreased energy, which may stabilize the R140A/IL-1RI/IL-1RAcP complex. In conclusion, the mutants Q19A and R140A are effective adjuvants that accelerate and enhance chicken mucosal immunity when co-administered with one dose of the NDV vaccine.


Subject(s)
Chickens/immunology , Immunity, Mucosal/immunology , Interleukin-1beta/immunology , Viral Vaccines/immunology , Adjuvants, Immunologic/administration & dosage , Amino Acid Sequence , Animals , Antibodies, Viral/immunology , Immunoglobulin A/immunology , Interferon-gamma/immunology , Interleukin-1 Receptor Accessory Protein/immunology , Newcastle Disease/immunology , Newcastle disease virus/immunology , Receptors, Interleukin-1 Type I/immunology , Vaccination/methods
7.
Oncotarget ; 8(28): 45133-45142, 2017 Jul 11.
Article in English | MEDLINE | ID: mdl-28415830

ABSTRACT

Ionizing radiation-induced pulmonary injury is a major limitation of radiotherapy for thoracic tumors. We have demonstrated that triptolide (TPL) could alleviate IR-induced pneumonia and pulmonary fibrosis. In this study, we explored the underlying mechanism by which TPL mitigates the effects of radiotoxicity. The results showed that:(1) Alveolar macrophages (AMs) were the primary inflammatory cells infiltrating irradiated lung tissues and were maintained at a high level for at least 17 days, which TPL could reduce by inhibiting of the production of macrophage inflammatory protein-2 (MIP-2) and its receptor CXCR2.(2) Stimulated by the co-cultured irradiated lung epithelium, AMs produced a panel of inflammative molecules (IMs), such as cytokines (TNF-α, IL-6, IL-1α, IL-1ß) and chemokines (MIP-2, MCP-1, LIX). TPL-treated AMs could reduce the production of these IMs. Meanwhile, AMs isolated from irradiated lung tissue secreted significantly high levels of IMs, which could be dramatically reduced by TPL.(3) TPL suppressed the phagocytosis of AMs as well as ROS production.Our results indicate that TPL mitigates radiation-induced pulmonary inflammation through the inhibition of the infiltration, IM secretion, and phagocytosis of AMs.


Subject(s)
Antineoplastic Agents, Alkylating/adverse effects , Diterpenes/adverse effects , Macrophages, Alveolar/pathology , Phenanthrenes/adverse effects , Pneumonia/chemically induced , Antineoplastic Agents, Alkylating/pharmacology , Diterpenes/pharmacology , Epoxy Compounds/adverse effects , Epoxy Compounds/pharmacology , Humans , Inflammation/pathology , Phenanthrenes/pharmacology , Pneumonia/pathology
8.
Bioorg Med Chem ; 24(18): 4263-4271, 2016 09 15.
Article in English | MEDLINE | ID: mdl-27448774

ABSTRACT

In an effort to develop new drug candidates with enhanced anticancer activity, our team synthesized and assessed the cytotoxicity of a series of novel xanthone derivatives with two longer 3,6-disubstituted amine carbonyl methoxy side chains on either benzene ring in selected human cancer cell lines. An MTT assay revealed that a set of compounds with lower IC50 values than the positive control, 5-FU, exhibited greater anticancer effects. The most potent derivative (XD8) exhibited anticancer activity in MDA-MB-231, PC-3, A549, AsPC-1, and HCT116 cells lines with IC50 values of 8.06, 6.18, 4.59, 4.76, and 6.09µM, respectively. Cell cycle analysis and apoptosis activation suggested that the mechanism of action of these derivatives includes cell cycle regulation and apoptosis induction.


Subject(s)
Antineoplastic Agents/pharmacology , Xanthones/pharmacology , Antineoplastic Agents/chemical synthesis , Apoptosis/drug effects , Caspase 3/metabolism , Caspase 7/metabolism , Cell Line, Tumor , Drug Screening Assays, Antitumor , G1 Phase Cell Cycle Checkpoints/drug effects , G2 Phase Cell Cycle Checkpoints/drug effects , Humans , Structure-Activity Relationship , Xanthones/chemical synthesis
9.
Cancer Biol Ther ; 17(4): 381-9, 2016 04 02.
Article in English | MEDLINE | ID: mdl-27003327

ABSTRACT

PURPOSE: IR-induced pulmonary fibrosis is one of the most severe late complications of radiotherapy for lung cancer. It is urgently needed to discover a new drug for anti-IR lung fibrosis. Our previous studies have indicated that TPL exhibits both anti-IR lung fibrosis and anti-tumor activities. To reveal the mechanism of TPL on anti-IR lung fibrosis, alveolar macrophages (AMs) were examined for TPL effect on their axis of Nicotinamide adenine dinucleotide phosphate oxidase-reactive oxygen species (NOXes-ROS) and myofibroblast activation. METHODS AND MATERIALS: The fibrosis-prone C57BL/6 mice were irradiated with 15 Gy on whole chest, then one day later, mice were treated without or with TPL (i.v. 0.25 mg/kg, qod for 1 month). The AMs were collected from bronchoalveolar lavage fluids and studied for the production of ROS and the levels of NOXes. The effect of AMs on myofibroblast activation as labeled with F4/80 or α-SMA (α-smooth muscle actin) were examined using flow cytometry, Western blotting, or immunohistochemical staining. RESULTS: TPL effectively reduced the IR-induced lung fibrosis as evidenced by the less myofibroblasts, less collagen deposit and less ROS in the IR-lung tissues. We found that ROS which responsible for myofibroblasts activation was mainly from AMs and was NOX2 and NOX4 dependent. TPL significantly reduced the infiltrated AMs in IR-lung tissues, and in addition, down regulated the level of NOX2 and NOX4 in AMs both in vitro and in vivo. Furthermore, by inhibiting NOXes dependent ROS in AMs, TPL deprived AMs' paracrine activation of myofibroblasts. CONCLUSIONS: Our work demonstrated that the anti-fibrotic effect of TPL on IR-induced pulmonary fibrosis was related to its inhibition on the axis of alveolar macrophages-NOXes-ROS-myofibroblasts.


Subject(s)
Antineoplastic Agents, Alkylating/therapeutic use , Diterpenes/therapeutic use , Macrophages, Alveolar/metabolism , Myofibroblasts/metabolism , Phenanthrenes/therapeutic use , Animals , Antineoplastic Agents, Alkylating/administration & dosage , Antineoplastic Agents, Alkylating/pharmacology , Diterpenes/administration & dosage , Diterpenes/pharmacology , Epoxy Compounds/administration & dosage , Epoxy Compounds/pharmacology , Epoxy Compounds/therapeutic use , Female , Humans , Macrophages, Alveolar/pathology , Mice , Mice, Inbred C57BL , Myofibroblasts/pathology , Phenanthrenes/administration & dosage , Phenanthrenes/pharmacology , Pulmonary Fibrosis , Reactive Oxygen Species
10.
Radiat Res ; 184(5): 509-17, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26488756

ABSTRACT

Triptolide (TPL) may mitigate radiation-induced late pulmonary side effects through its inhibition of global pro-inflammatory cytokines. In this study, we evaluated the effect of TPL in C57BL/6 mice, the animals were exposed to radiation with vehicle (15 Gy), radiation with TPL (0.25 mg/kg i.v., twice weekly for 1, 2 and 3 months), radiation and celecoxib (CLX) (30 mg/kg) and sham irradiation. Cultured supernatant of irradiated RAW 264.7 and MLE-15 cells and lung lysate in different groups were enzyme-linked immunosorbent assays at 33 h. Respiratory rate, pulmonary compliance and pulmonary density were measured at 5 months in all groups. The groups exposed to radiation with vehicle and radiation with TPL exhibited significant differences in respiratory rate and pulmonary compliance (480 ± 75/min vs. 378 ± 76/min; 0.6 ± 0.1 ml/cm H2O/p kg vs. 0.9 ± 0.2 ml/cm H2O/p kg). Seventeen cytokines were significantly reduced in the lung lysate of the radiation exposure with TPL group at 5 months compared to that of the radiation with vehicle group, including profibrotic cytokines implicated in pulmonary fibrosis, such as IL-1ß, TGF- ß1 and IL-13. The radiation exposure with TPL mice exhibited a 41% reduction of pulmonary density and a 25% reduction of hydroxyproline in the lung, compared to that of radiation with vehicle mice. The trichrome-stained area of fibrotic foci and pathological scaling in sections of the mice treated with radiation and TPL mice were significantly less than those of the radiation with vehicle-treated group. In addition, the radiation with TPL-treated mice exhibited a trend of improved survival rate compared to that of the radiation with vehicle-treated mice at 5 months (83% vs. 53%). Three radiation-induced profibrotic cytokines in the radiation with vehicle-treated group were significantly reduced by TPL treatment, and this partly contributed to the trend of improved survival rate and pulmonary density and function and the decreased severity of pulmonary fibrosis at 5 months. Our findings indicate that TPL could be a potential new agent to mitigate radiation-induced pulmonary fibrosis.


Subject(s)
Diterpenes/pharmacology , Phenanthrenes/pharmacology , Pulmonary Fibrosis/drug therapy , Radiation Pneumonitis/drug therapy , Radiation-Protective Agents/pharmacology , Animals , Collagen/metabolism , Cytokines/biosynthesis , Diterpenes/therapeutic use , Epoxy Compounds/pharmacology , Epoxy Compounds/therapeutic use , Female , Lung/drug effects , Lung/pathology , Lung/physiopathology , Lung/radiation effects , Mice , Mice, Inbred C57BL , Organ Size/drug effects , Organ Size/radiation effects , Phenanthrenes/therapeutic use , Pulmonary Fibrosis/metabolism , Pulmonary Fibrosis/pathology , Pulmonary Fibrosis/physiopathology , RAW 264.7 Cells , Radiation Pneumonitis/metabolism , Radiation Pneumonitis/pathology , Radiation Pneumonitis/physiopathology , Radiation-Protective Agents/therapeutic use , Survival Rate
11.
Radiat Res ; 183(2): 188-95, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25574588

ABSTRACT

We developed a simple, rapid and quantitative assay using the fluorescent probe PicoGreen to measure the concentration of ionizing radiation-induced double-stranded DNA (dsDNA) in mouse plasma, and we correlated this concentration with the radiation dose. With 70 µl of blood obtained by fingerstick, this 30 min assay reduces protein interference without extending sample processing time. Plasma from nonirradiated mice (BALB/c and NIH Swiss) was pooled, diluted and spiked with dsDNA to establish sensitivity and reproducibility of the assay to quantify plasma dsDNA. The assay was then used to directly quantify dsDNA in plasma at 0-48 h after mice received 0-10 Gy total-body irradiation (TBI). There are three optimal conditions for this assay: 1:10 dilution of plasma in water; 1:200 dilution of PicoGreen reagent in water; and calibration of radiation-induced dsDNA concentration through a standard addition method using serial spiking of samples with genomic dsDNA. Using the internal standard calibration curve of the spiked samples method, the signal developed within 5 min, exhibiting a linear signal (r(2) = 0.997). The radiation-induced elevation of plasma DNA in mice started at 1-3 h, peaked at 9 h and gradually returned to baseline at 24 h after TBI (6 Gy). DNA levels in plasma collected from mice 9 h after 0-10 Gy TBI correlated strongly with dose (r(2) = 0.991 and 0.947 for BALB/c and NIH Swiss, respectively). Using the PicoGreen assay, we observed a radiation dose-dependent response in extracellular plasma DNA 9 h after irradiation with an assay time ≤ 30 min.


Subject(s)
Biological Assay/methods , DNA Damage , DNA, Circular/blood , DNA, Circular/radiation effects , Radiation Monitoring/methods , Animals , DNA, Circular/chemistry , Dose-Response Relationship, Radiation , Fluorescent Dyes/chemistry , Fluorescent Dyes/radiation effects , Male , Mice , Mice, Inbred BALB C , Organic Chemicals/chemistry , Organic Chemicals/radiation effects , Radiation Dosage , Reproducibility of Results , Sensitivity and Specificity , Whole-Body Irradiation
12.
Int J Cell Biol ; 2014: 850460, 2014.
Article in English | MEDLINE | ID: mdl-24688546

ABSTRACT

We investigated whether genetic radiosensitivity-related changes in mtDNA/nDNA ratios are significant to mitochondrial function and if a material effect on mtDNA content and function exists. BALB/c (radiosensitive), C57BL/6 (radioresistant), and F1 hybrid mouse strains were exposed to total body irradiation. Hepatic genomic DNA was extracted, and mitochondria were isolated. Mitochondrial oxygen consumption, ROS, and calcium-induced mitochondrial swelling were measured. Radiation influenced strain-specific survival in vivo. F1 hybrid survival was influenced by maternal input. Changes in mitochondrial content corresponded to survival in vivo among the 4 strains. Calcium-induced mitochondrial swelling was strain dependent. Isolated mitochondria from BALB/c mice were significantly more sensitive to calcium overload than mitochondria from C57BL/6 mice. Maternal input partially influenced the recovery effect of radiation on calcium-induced mitochondrial swelling in F1 hybrids; the hybrid with a radiosensitive maternal lineage exhibited a lower rate of recovery. Hybrids had a survival rate that was biased toward maternal input. mtDNA content and mitochondrial permeability transition pores (MPTP) measured in these strains before irradiation reflected a dominant input from the parent. After irradiation, the MPTP opened sooner in radiosensitive and hybrid strains, likely triggering intrinsic apoptotic pathways. These findings have important implications for translation into predictors of radiation sensitivity/resistance.

13.
Health Phys ; 106(6): 704-12, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24776903

ABSTRACT

The effects of fibroblast growth factors and their potential as broad-spectrum agents to treat and mitigate radiation injury have been studied extensively over the past two decades. This report shows that a peptide mimetic of basic fibroblast growth factor (FGF-P) protects and mitigates against acute radiation syndromes. FGF-P attenuates both sepsis and bleeding in a radiation-induced bone marrow syndrome model and reduces the severity of gastrointestinal and cutaneous syndromes; it should also mitigate combined injuries. FGF-2 and FGF-P induce little or no deleterious inflammation or vascular leakage, which distinguishes them from most other growth factors, angiogenic factors, and cytokines. Although recombinant FGFs have proven safe in several ongoing clinical trials, they are expensive to synthesize, can only be produced in limited quantity, and have limited shelf life. FGF-P mimics the advantageous features of FGF-2 without these disadvantages. This paper shows that FGF-P not only has the potential to be a potent yet safe broad-spectrum medical countermeasure that mitigates acute radiotoxicity but also holds promise for thermal burns, ischemic wound healing, tissue engineering, and stem-cell regeneration.


Subject(s)
Acute Radiation Syndrome/prevention & control , Fibroblast Growth Factor 2/analogs & derivatives , Fibroblast Growth Factor 2/pharmacology , Radiation-Protective Agents/chemistry , Radiation-Protective Agents/pharmacology , Acute Radiation Syndrome/blood , Acute Radiation Syndrome/drug therapy , Acute Radiation Syndrome/metabolism , Animals , Blood Coagulation/drug effects , Blood Coagulation/radiation effects , Bone Marrow Cells/cytology , Cell Line , Cell Proliferation/drug effects , Cell Proliferation/radiation effects , Cell Survival/drug effects , Cell Survival/radiation effects , Drug Stability , Enzyme Activation/drug effects , Enzyme Activation/radiation effects , Fibroblast Growth Factor 2/adverse effects , Fibroblast Growth Factor 2/pharmacokinetics , Lethal Dose 50 , Mice , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Phosphoproteins/metabolism , Platelet Count , Radiation-Protective Agents/adverse effects , Radiation-Protective Agents/pharmacokinetics , Stem Cells/cytology , Stem Cells/drug effects , Stem Cells/radiation effects
14.
Adv Exp Med Biol ; 812: 149-155, 2014.
Article in English | MEDLINE | ID: mdl-24729227

ABSTRACT

The tumor vascular system, which is critical to the survival and growth of solid tumors, has been an attractive target for anticancer research. Building on studies that show that some flavonoids have anticancer vascular effects, we developed and analyzed the flavonoid derivative R24 [3, 6-bis (2-oxiranylmethoxy)-9H-xanthen-9-one]. A CAM assay revealed that R24 disrupted neovascular formation; fewer dendrites were detected and overall dendritic length was shorter in the R24-treated chicken embryos. The antiproliferative effect of R24 was measured by MTT assay in A549 (lung cancer), AsPC-1 (pancreatic cancer), HCT-116 (colorectal cancer), and PC-3 (prostate cancer) cell lines. R24 reduced proliferation with an IC50 of 3.44, 3.59, 1.22, and 11.83 µM, respectively. Cell-cycle analysis and Annexin-V/propidium iodide staining showed that R24 induced apoptosis. In addition, R24 regulated intracellular ROS production in a dose-dependent manner. CM-H2DCFDA staining indicated that intracellular ROS production increased with the R24 dose. In summary, we found that R24 exhibits potent antiangiogenic and antiproliferative effects, induces apoptosis, and promotes ROS production.


Subject(s)
Flavonoids/pharmacology , Neoplasms/blood supply , Neovascularization, Pathologic/prevention & control , Reactive Oxygen Species/metabolism , Cell Line, Tumor , Humans
15.
PLoS One ; 8(10): e74272, 2013.
Article in English | MEDLINE | ID: mdl-24204567

ABSTRACT

Most human pancreatic cancer cells are resistant to tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis. However, the mechanisms by which pancreatic cancer cells utilize their extracellular molecules to counteract the proapoptotic signaling mediated by the TNF family are largely unknown. In this study, we demonstrate for the first time that DcR3, a secreted decoy receptor that malignant pancreatic cancer cells express at a high level, acts as an extracellular antiapoptotic molecule by binding to TRAIL and counteracting its death-promoting function. The reduction of DcR3 with siRNA unmasked TRAIL and greatly enhanced TRAIL-induced apoptosis. Gemcitabine, a first-line drug for pancreatic cancer, also reduced the level of DcR3. The addition of DcR3 siRNA further enhanced gemcitabine-induced apoptosis. Notably, our in vivo study demonstrated that the therapeutic effect of gemcitabine could be enhanced via further reduction of DcR3, suggesting that downregulation of DcR3 in tumor cells could tip the balance of pancreatic cells towards apoptosis and potentially serve as a new strategy for pancreatic cancer therapy.


Subject(s)
Apoptosis/genetics , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/metabolism , Receptors, Tumor Necrosis Factor, Member 6b/genetics , TNF-Related Apoptosis-Inducing Ligand/metabolism , Animals , Antimetabolites, Antineoplastic/pharmacology , Apoptosis/drug effects , Cell Line, Tumor , Deoxycytidine/administration & dosage , Deoxycytidine/analogs & derivatives , Deoxycytidine/pharmacology , Disease Models, Animal , Gene Expression Regulation, Neoplastic/drug effects , Humans , Mice , Pancreatic Neoplasms/pathology , Protein Binding , RNA Interference , Receptors, Tumor Necrosis Factor, Member 6b/metabolism , Tumor Burden/drug effects , Tumor Burden/genetics , Tumor Necrosis Factor Ligand Superfamily Member 14/metabolism , Xenograft Model Antitumor Assays , Gemcitabine
16.
PLoS One ; 8(8): e71347, 2013.
Article in English | MEDLINE | ID: mdl-23977023

ABSTRACT

Icaritin (ICT) is a hydrolytic form of icariin isolated from plants of the genus Epimedium. This study was to investigate the radiosensitization effect of icaritin and its possible underlying mechanism using murine 4T1 breast cancer cells. The combination of Icaritin at 3 µM or 6 µM with 6 or 8 Gy of ionizing radiation (IR) in the clonogenic assay yielded an ER (enhancement ratio) of 1.18 or 1.28, CI (combination index) of 0.38 or 0.19 and DRI (dose reducing index) of 2.51 or 5.07, respectively. These strongly suggest that Icaritin exerted a synergistic killing (?) effect with radiation on the tumor cells. This effect might relate with bioactivities of ICT: 1) exert an anti-proliferative effect in a dose- and time-dependent manner, which is different from IR killing effect but likely work together with the IR effect; 2) suppress the IR-induced activation of two survival paths, ERK1/2 and AKT; 3) induce the G2/M blockage, enhancing IR killing effect; and 4) synergize with IR to enhance cell apoptosis. In addition, ICT suppressed angiogenesis in chick embryo chorioallantoic membrane (CAM) assay. Taken together, ICT is a new radiosensitizer and can enhance anti-cancer effect of IR or other therapies.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Flavonoids/pharmacology , Mammary Glands, Animal/drug effects , Radiation Tolerance/drug effects , Radiation-Sensitizing Agents/pharmacology , Animals , Apoptosis/drug effects , Apoptosis/radiation effects , Cell Line, Tumor , Chick Embryo , Chorioallantoic Membrane/blood supply , Chorioallantoic Membrane/drug effects , Dose-Response Relationship, Drug , Dose-Response Relationship, Radiation , Female , G2 Phase Cell Cycle Checkpoints/drug effects , G2 Phase Cell Cycle Checkpoints/radiation effects , Gene Expression Regulation , Mammary Glands, Animal/metabolism , Mammary Glands, Animal/pathology , Mice , Mitogen-Activated Protein Kinase 1/genetics , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/genetics , Mitogen-Activated Protein Kinase 3/metabolism , Neovascularization, Physiologic/drug effects , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , Radiation, Ionizing , Signal Transduction
17.
Adv Exp Med Biol ; 789: 195-201, 2013.
Article in English | MEDLINE | ID: mdl-23852495

ABSTRACT

Amifostine is a first-line cytoprotective drug used to prevent radiotherapy-induced or chemotherapy-induced injuries. However, its mechanism of action is not well understood. In this study, freshly harvested bone marrow cells were treated with amifostine and analyzed with a series of mitochondrial indices. In vitro results showed that bone marrow cells treated with amifostine 0.5 h before irradiation (0.5 Gy) experienced several benefits, as compared to vehicle controls, including (1) reduced reactive oxygen species levels, which reduced the production of free radicals; (2) better preservation of mitochondria, as indicated by MitoTracker-positive staining and the increased intensity of staining; (3) reduced apoptosis, as demonstrated by Annexin V staining; and (4) a better proliferation rate, as illustrated by MTT assay. Our in vitro studies showed that amifostine-treated mice exhibited (1) higher ATP production; (2) reduced plasma IL-2 levels, suppressing the immune response triggered by radiotoxicity; and (3) enhanced radiation-induced production of granulocyte colony-stimulating factor. All of these processes benefit recovery from radiation-induced damage.


Subject(s)
Amifostine/pharmacology , Bone Marrow Cells/drug effects , Bone Marrow/drug effects , Cytokines/metabolism , Mitochondria/drug effects , Radiation-Protective Agents/pharmacology , Adaptation, Physiological/drug effects , Adenosine Triphosphate/metabolism , Animals , Bone Marrow/growth & development , Bone Marrow/metabolism , Bone Marrow Cells/metabolism , Male , Mice , Mitochondria/metabolism , Reactive Oxygen Species/metabolism
18.
Adv Exp Med Biol ; 789: 257-264, 2013.
Article in English | MEDLINE | ID: mdl-23852503

ABSTRACT

Interleukin 11 (IL-11) is a multifunctional cytokine isolated from bone marrow (BM)-derived stromal cells that promotes hematopoiesis and prolongs the life span of lethally irradiated animals. However, the underlying mechanism for the protective effect of IL-11 on BM is unclear. In this study, we explored the effect of IL-11 on irradiated BM cells. Freshly harvested BM cells were pretreated with 20 ng/ml of recombinant IL-11 for 30 min, irradiated with a dose of 0.5 Gy, cultured for 24 h, and then subjected to several assays. In vitro data showed that, as compared to the vehicle controls, IL-11: (1) reduced the production of reactive oxygen species; (2) reduced the alteration of mitochondrial membrane potential; (3) increased MitoTracker staining, suggesting that the number of mitochondria and their functions were better maintained; and (4) reduced apoptosis of BM cells and enhanced BM cell proliferation. In vivo studies of mice pretreated with saline or 100 µg/kg of IL-11 at 12 and 2 h before 10-Gy total body irradiation (TBI) demonstrated that G-CSF and IL-6 were significantly upregulated, whereas IL-2 and IL-4 were reduced. We found that IL-11 protects mitochondrial functions, acts with G-CSF and IL-6 to stimulate the growth of radiation-damaged BM, and reduces the immune response to radiation injury.


Subject(s)
Bone Marrow/drug effects , Bone Marrow/radiation effects , Interleukin-11/pharmacology , Mitochondria/drug effects , Mitochondria/radiation effects , Radiation Injuries, Experimental/metabolism , Radiation Injuries, Experimental/prevention & control , Animals , Apoptosis/drug effects , Apoptosis/radiation effects , Bone Marrow/metabolism , Bone Marrow Cells/metabolism , Bone Marrow Cells/radiation effects , Cell Growth Processes/drug effects , Cell Growth Processes/radiation effects , Granulocyte Colony-Stimulating Factor/metabolism , Interleukin-11/metabolism , Interleukin-6/metabolism , Male , Membrane Potential, Mitochondrial/drug effects , Membrane Potential, Mitochondrial/radiation effects , Mice , Mitochondria/metabolism , Reactive Oxygen Species/metabolism , Whole-Body Irradiation/methods
19.
Adv Exp Med Biol ; 789: 273-280, 2013.
Article in English | MEDLINE | ID: mdl-23852505

ABSTRACT

In this study, we investigated the response of irradiated bone marrow cells to granulocyte colony-stimulating factor (G-CSF). Freshly harvested bone marrow cells were treated with either saline (vehicle control) or 20 ng/ml of G-CSF. Thereafter, cells were separated into nonirradiated (no-IR) and irradiated (IR, 0.5 Gy) groups. IR cells exhibited a higher proliferation rate in response to G-CSF, as compared to the no-IR cells. Reduced levels of reactive oxygen species indicated that G-CSF-treated IR cells produced fewer free radicals, as compared to the no-IR cells. The G-CSF-treated IR cells also had a lower apoptotic rate than their no-IR counterparts. Furthermore, G-CSF-treated IR cells exhibited less alteration of mitochondrial membrane potential, as compared to the no-IR cells. Finally, the mitochondrial number increased in the G-CSF-treated IR cells. The radiation-induced increase in plasma IL-6 in vivo could be enhanced by the administration of G-CSF. The data suggest that radiation potentiates the response of bone marrow cells to G-CSF treatment.


Subject(s)
Bone Marrow/drug effects , Bone Marrow/radiation effects , Granulocyte Colony-Stimulating Factor/pharmacology , Animals , Bone Marrow/metabolism , Bone Marrow Cells/drug effects , Bone Marrow Cells/metabolism , Bone Marrow Cells/radiation effects , Free Radicals/metabolism , Interleukin-6/blood , Male , Membrane Potential, Mitochondrial/drug effects , Membrane Potential, Mitochondrial/radiation effects , Mice , Mitochondria/drug effects , Mitochondria/metabolism , Mitochondria/radiation effects , Reactive Oxygen Species/metabolism
20.
Adv Exp Med Biol ; 765: 47-53, 2013.
Article in English | MEDLINE | ID: mdl-22879013

ABSTRACT

In this study, we compared two in vitro collagen production assays ([(3)H]-proline incorporation and Sirius Red) for their ability to determine the pattern shift from soluble to deposited collagen. The effect of the antifibrotic agent, triptolide (TPL), on collagen production was also studied. The results showed that: (1) 48 h after NIH 3T3 (murine embryo fibroblast) and HFL-1(human fetal lung fibroblast) were exposed to transforming growth factor-beta 1 (TGF-ß), there was an increase in soluble collagen in the culture medium; (2) on day 4, soluble collagen declined, whereas deposited collagen increased; (3) Sirius Red was easier to use than [(3)H]-proline incorporation and more consistently reflected the collagen pattern shift from soluble to deposited; (4) the in vitro Sirius Red assay took less time than the in vivo assay to determine the effect of TPL. Our results suggest that: (a) the newly synthesized soluble collagen can sensitively evaluate an agent's capacity for collagen production and (b) Sirius Red is more useful than [(3)H]-proline because it is easier to use, more convenient, less time consuming, and does not require radioactive material.


Subject(s)
Azo Compounds , Biological Assay , Collagen/metabolism , Embryo, Mammalian/metabolism , Fetus/metabolism , Fibroblasts/metabolism , Lung/metabolism , Animals , Antineoplastic Agents, Alkylating/pharmacology , Cells, Cultured , Coloring Agents , Diterpenes/pharmacology , Embryo, Mammalian/cytology , Embryo, Mammalian/drug effects , Epoxy Compounds/pharmacology , Fetus/cytology , Fetus/drug effects , Fibroblasts/cytology , Fibroblasts/drug effects , Humans , Lung/cytology , Lung/drug effects , Mice , NIH 3T3 Cells , Phenanthrenes/pharmacology , Proline/metabolism , Transforming Growth Factor beta/pharmacology
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