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1.
Nucleic Acids Res ; 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38936834

ABSTRACT

R-loops cause genome instability, disrupting normal cellular functions. Histone acetylation, particularly by p300/CBP-associated factor (PCAF), is essential for maintaining genome stability and regulating cellular processes. Understanding how R-loop formation and resolution are regulated is important because dysregulation of these processes can lead to multiple diseases, including cancer. This study explores the role of PCAF in maintaining genome stability, specifically for R-loop resolution. We found that PCAF depletion promotes the generation of R-loop structures, especially during ongoing transcription, thereby compromising genome stability. Mechanistically, we found that PCAF facilitates histone H4K8 acetylation, leading to recruitment of the a double-strand break repair protein (MRE11) and exonuclease 1 (EXO1) to R-loop sites. These in turn recruit Fanconi anemia (FA) proteins, including FANCM and BLM, to resolve the R-loop structure. Our findings suggest that PCAF, histone acetylation, and FA proteins collaborate to resolve R-loops and ensure genome stability. This study therefore provides novel mechanistic insights into the dynamics of R-loops as well as the role of PCAF in preserving genome stability. These results may help develop therapeutic strategies to target diseases associated with genome instability.


R-loops are harmful DNA-RNA hybrid structures that cause genome instability, disrupting normal cell functions. This study explored the role of the protein PCAF in resolving R-loops to maintain genome stability. The researchers found that depleting PCAF leads to increased R-loop formation, especially during transcription, compromising the genome. Mechanistically, PCAF facilitates histone acetylation, recruiting proteins like MRE11, EXO1, FANCM and BLM to R-loop sites. These proteins collaborate to resolve R-loop structures. The findings suggest that PCAF, histone acetylation, and these repair proteins work together to untangle R-loops and preserve genome integrity. Understanding this process provides insights into R-loop dynamics and PCAF's role in genome maintenance, potentially leading to therapeutic strategies for diseases associated with genome instability, such as cancer.

2.
Eur J Med Chem ; 272: 116459, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38704942

ABSTRACT

Activation of the aminopeptidase (AP) activity of leukotriene A4 hydrolase (LTA4H) presents a potential therapeutic strategy for resolving chronic inflammation. Previously, ARM1 and derivatives were found to activate the AP activity using the alanine-p-nitroanilide (Ala-pNA) as a reporter group in an enzyme kinetics assay. As an extension of this previous work, novel ARM1 derivatives were synthesized using a palladium-catalyzed Ullmann coupling reaction and screened using the same assay. Analogue 5, an aminopyrazole (AMP) analogue of ARM1, was found to be a potent AP activator with an AC50 of 0.12 µM. An X-ray crystal structure of LTA4H in complex with AMP was refined at 2.7 Å. Despite its AP activity with Ala-pNA substrate, AMP did not affect hydrolysis of the previously proposed natural ligand of LTA4H, Pro-Gly-Pro (PGP). This result highlights a discrepancy between the hydrolysis of more conveniently monitored chromogenic synthetic peptides typically employed in assays and endogenous peptides. The epoxide hydrolase (EH) activity of AMP was measured in vivo and the compound significantly reduced leukotriene B4 (LTB4) levels in a murine bacterial pneumonia model. However, AMP did not enhance survival in the murine pneumonia model over a 14-day period. A liver microsome stability assay showed metabolic stability of AMP. The results suggested that accelerated Ala-pNA cleavage is not sufficient for predicting therapeutic potential, even when the full mechanism of activation is known.


Subject(s)
Epoxide Hydrolases , Epoxide Hydrolases/antagonists & inhibitors , Epoxide Hydrolases/metabolism , Animals , Mice , Structure-Activity Relationship , Humans , Molecular Structure , Aminopeptidases/metabolism , Aminopeptidases/antagonists & inhibitors , Ethers/pharmacology , Ethers/chemistry , Ethers/chemical synthesis , Dose-Response Relationship, Drug , Models, Molecular , Crystallography, X-Ray
3.
J Biol Eng ; 18(1): 31, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38715085

ABSTRACT

Alcohol consumption, a pervasive societal issue, poses considerable health risks and socioeconomic consequences. Alcohol-induced hepatic disorders, such as fatty liver disease, alcoholic hepatitis, chronic hepatitis, liver fibrosis, and cirrhosis, underscore the need for comprehensive research. Existing challenges in mimicking chronic alcohol exposure in cellular systems, attributed to ethanol evaporation, necessitate innovative approaches. In this study, we developed a simple, reusable, and controllable device for examining the physiological reactions of hepatocytes to long-term alcohol exposure. Our approach involved a novel device designed to continuously release ethanol into the culture medium, maintaining a consistent ethanol concentration over several days. We evaluated device performance by examining gene expression patterns and cytokine secretion alterations during long-term exposure to ethanol. These patterns were correlated with those observed in patients with alcoholic hepatitis. Our results suggest that our ethanol-releasing device can be used as a valuable tool to study the mechanisms of chronic alcohol-mediated hepatic diseases at the cellular level. Our device offers a practical solution for studying chronic alcohol exposure, providing a reliable platform for cellular research. This innovative tool holds promise for advancing our understanding of the molecular processes involved in chronic alcohol-mediated hepatic diseases. Future research avenues should explore broader applications and potential implications for predicting and treating alcohol-related illnesses.

4.
Int J Mol Sci ; 24(23)2023 Nov 24.
Article in English | MEDLINE | ID: mdl-38069026

ABSTRACT

Colorectal cancer (CRC) is one of the most common and deadly cancers in the world. However, no effective treatment for the disease has yet been found. For this reason, several studies are being carried out on the treatment of CRC. Currently, there is limited understanding of the role of CPNE7 (copine-7) in CRC progression and metastasis. The results of this study show that CPNE7 exerts an oncogenic effect in CRC. First, CPNE7 was shown to be significantly up-regulated in CRC patient tissues and CRC cell lines compared to normal tissues according to IHC staining, qRT-PCR, and western blotting. Next, this study used both systems of siRNA and shRNA to suppress CPNE7 gene expression to check the CPNE7 mechanism in CRC. The suppressed CPNE7 significantly inhibited the growth of CRC cells in in vitro experiments, including migration, invasion, and semisolid agar colony-forming assay. Moreover, the modified expression of CPNE7 led to a decrease in the levels of genes associated with epithelial-mesenchymal transition (EMT). The epithelial genes E-cadherin (CDH1) and Collagen A1 were upregulated, and the levels of mesenchymal genes such as N-cadherin (CDH2), ZEB1, ZEB2, and SNAIL (SNAL1) were downregulated after CPNE7 inhibition. This study suggests that CPNE7 may serve as a potential diagnostic biomarker for CRC patients.


Subject(s)
Colorectal Neoplasms , Signal Transduction , Humans , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Colorectal Neoplasms/pathology , Epithelial-Mesenchymal Transition/genetics , Gene Expression Regulation, Neoplastic , Neoplasm Metastasis , RNA, Small Interfering/genetics
5.
Vision Res ; 213: 108317, 2023 12.
Article in English | MEDLINE | ID: mdl-37722240

ABSTRACT

Gene therapy is a flourishing field with the potential to revolutionize the treatment of genetic diseases. The emergence of CRISPR-Cas9 has significantly advanced targeted and efficient genome editing. Although CRISPR-Cas9 has demonstrated promising potential applications in various genetic disorders, it faces limitations in simultaneously targeting multiple genes. Novel CRISPR systems, such as Cas12 and Cas13, have been developed to overcome these challenges, enabling multiplexing and providing unique advantages. Cas13, in particular, targets mRNA instead of genomic DNA, permitting precise gene expression control and mitigating off-target effects. This review investigates the potential of Cas12 and Cas13 in ocular gene therapy applications, such as suppression of inflammation and cell death. In addition, the capabilities of Cas12 and Cas13 are explored in addressing potential targets related with disease mechanisms such as aberrant isoforms, mitochondrial genes, cis-regulatory sequences, modifier genes, and long non-coding RNAs. Anatomical accessibility and relative immune privilege of the eye provide an ideal organ system for evaluating these novel techniques' efficacy and safety. By targeting multiple genes concurrently, CRISPR-Cas12 and Cas13 systems hold promise for treating a range of ocular disorders, including glaucoma, retinal dystrophies, and age-related macular degeneration. Nonetheless, additional refinement is required to ascertain the safety and efficacy of these approaches in ocular disease treatments. Thus, the development of Cas12 and Cas13 systems marks a significant advancement in gene therapy, offering the potential to devise effective treatments for ocular disorders.


Subject(s)
CRISPR-Cas Systems , Eye Diseases , Humans , CRISPR-Cas Systems/genetics , Gene Editing , RNA, Messenger , Eye , Eye Diseases/genetics , Eye Diseases/therapy
6.
World J Gastrointest Surg ; 15(5): 992-999, 2023 May 27.
Article in English | MEDLINE | ID: mdl-37342841

ABSTRACT

BACKGROUND: Leiomyosarcoma (LMS) has a poor prognosis and rarely originates from the colon. If resection is possible, surgery is the first treatment most commonly considered. Unfortunately, no standard treatment exists for hepatic metastasis of LMS; although, several treatments, such as chemotherapy, radiotherapy, and surgery, have been used. Subsequently, the management of liver metastases remains controversial. CASE SUMMARY: We present a rare case of metachronous liver metastasis in a patient with LMS originating from the descending colon. A 38-year-old man initially reported abdominal pain and diarrhea over the previous two months. Colonoscopy revealed a 4-cm diameter mass in the descending colon, 40 cm from the anal verge. Computed tomography revealed intussusception of the descending colon due to the 4-cm mass. The patient underwent a left hemicolectomy. Immunohistochemical analysis of the tumor revealed that it was positive for smooth muscle actin and desmin, and negative for cluster of differentiation 34 (CD34), CD117, and discovered on gastrointestinal stromal tumor (GIST)-1, which are characteristic of gastrointestinal LMS. A single liver metastasis developed 11 mo post-operatively; the patient subsequently underwent curative resection thereof. The patient remained disease-free after six cycles of adjuvant chemotherapy (doxorubicin and ifosfamide), and 40 and 52 mo after liver resection and primary surgery, respectively. Similar cases were obtained from a search of Embase, PubMed, MEDLINE, and Google Scholar. CONCLUSION: Early diagnosis and surgical resection may be the only potential curative options for liver metastasis of gastrointestinal LMS.

7.
Adv Drug Deliv Rev ; 199: 114973, 2023 08.
Article in English | MEDLINE | ID: mdl-37369262

ABSTRACT

RNA vaccines have demonstrated their ability to solve the issues posed by the COVID-19 pandemic. This success has led to the renaissance of research into mRNA and their nanoformulations as potential therapeutic modalities for various diseases. The potential of mRNA as a template for synthesizing proteins and protein fragments for cancer immunotherapy is now being explored. Despite the promise, the use of mRNA in cancer immunotherapy is limited by challenges, such as low stability against extracellular RNases, poor delivery efficiency to the target organs and cells, short circulatory half-life, variable expression levels and duration. This review highlights recent advances in chemical modification and advanced delivery systems that are helping to address these challenges and unlock the biological and pharmacological potential of mRNA therapeutics in cancer immunotherapy. The review concludes by discussing future perspectives for mRNA-based cancer immunotherapy, which holds great promise as a next-generation therapeutic modality.


Subject(s)
COVID-19 , Neoplasms , Humans , RNA, Messenger , Pandemics , COVID-19/therapy , Immunotherapy , Proteins
8.
Sci Rep ; 12(1): 9443, 2022 06 08.
Article in English | MEDLINE | ID: mdl-35676292

ABSTRACT

The aminopeptidase activity (AP) of the leukotriene A4 hydrolase (LTA4H) enzyme has emerged as a therapeutic target to modulate host immunity. Initial reports focused on the benefits of augmenting the LTA4H AP activity and clearing its putative pro-inflammatory substrate Pro-Gly-Pro (PGP). However, recent reports have introduced substantial complexity disconnecting the LTA4H modulator 4-methoxydiphenylmethane (4MDM) from PGP as follows: (1) 4MDM inhibits PGP hydrolysis and subsequently inhibition of LTA4H AP activity, and (2) 4MDM activates the same enzyme target in the presence of alternative substrates. Differential modulation of LTA4H by 4MDM was probed in a murine model of acute lung inflammation, which showed that 4MDM modulates the host neutrophilic response independent of clearing PGP. X-ray crystallography showed that 4MDM and PGP bind at the zinc binding pocket and no allosteric binding was observed. We then determined that 4MDM modulation is not dependent on the allosteric binding of the ligand, but on the N-terminal side chain of the peptide. In conclusion, our study revealed that a peptidase therapeutic target can interact with its substrate and ligand in complex biochemical mechanisms. This raises an important consideration when ligands are designed to explain some of the unpredictable outcomes observed in therapeutic discovery targeting LTA4H.


Subject(s)
Epoxide Hydrolases , Pneumonia , Animals , Disease Models, Animal , Ligands , Mice
9.
Trends Mol Med ; 28(8): 644-661, 2022 08.
Article in English | MEDLINE | ID: mdl-35641420

ABSTRACT

Ophthalmic neurodegenerative diseases encompass a wide array of molecular pathologies unified by calpain dysregulation. Calpains are calcium-dependent proteases that perpetuate cellular death and inflammation when hyperactivated. Calpain inhibition trials in other organs have faced pharmacological challenges, but the eye offers many advantages for the development and testing of targeted molecular therapeutics, including small molecules, peptides, engineered proteins, drug implants, and gene-based therapies. This review highlights structural mechanisms underlying calpain activation, distinct cellular expression patterns, and in vivo models that link calpain hyperactivity to human retinal and developmental disease. Optimizing therapeutic approaches for calpain-mediated eye diseases can help accelerate clinically feasible strategies for treating calpain dysregulation in other diseased tissues.


Subject(s)
Calpain , Retina , Calcium/metabolism , Calpain/metabolism , Cell Death , Humans , Retina/metabolism
10.
STAR Protoc ; 3(1): 101143, 2022 03 18.
Article in English | MEDLINE | ID: mdl-35141566

ABSTRACT

Ocular drug implants (ODIs) are beneficial for treating ocular diseases. However, the lack of a robust injection approach for small-eyed model organisms has been a major technical limitation in developing ODIs. Here, we present a cost-effective, minimally invasive protocol to deliver ODIs into the mouse vitreous called Mouse Implant Intravitreal Injection (MI3). MI3 provides two alternative surgical approaches (air-pressure or plunger) to deliver micro-scaled ODIs into milli-scaled eyes, and expands the preclinical platforms to determine ODIs' efficacy, toxicity, and pharmacokinetics. For complete details on the use and execution of this protocol, please refer to Sun et al. (2021).


Subject(s)
Vitreous Body , Animals , Drug Implants/pharmacology , Intravitreal Injections , Mice
11.
J Leukoc Biol ; 111(2): 439-450, 2022 02.
Article in English | MEDLINE | ID: mdl-33884654

ABSTRACT

Canine natural killer (NK) cells are large, granular lymphocytes that are neither B lymphocytes nor T lymphocytes. However, it has been reported that canine NK cells share some of the phenotypic characteristics of T lymphocytes, such as CD3 and CD5. Studies are needed to assess the safety of canine NK cells for immunotherapy, especially because the safety of using allogeneic NK cells as an immunotherapy for dogs has yet to be shown. In this study, the safety of cultured canine NK cells was assessed using a xenogeneic mouse model of graft-versus-host disease (GVHD). Mice were injected with either canine peripheral blood mononuclear cells (PBMCs) or cultured NK cells for 2 or 3 weeks. Data were then collected on changes in mice body weights, disease severity scores, and survival rates. Histopathological and immunohistochemical evaluations were also performed. All mice injected with canine PBMCs died within 45 days after injection. Severe clinical signs were caused by GVHD. The histopathological and immunohistochemical evaluations showed that mice injected with canine PBMCs had multiple lesions, including necrosis in their lungs, livers, kidneys, and stomachs, and the injected cells were present around the lesions. By contrast, no mice injected with cultured NK cells without removing the CD3+ TCR- cells exhibited any clinical abnormalities. Moreover, they all survived the 90-day experimental period without exhibiting any histopathological changes. Accordingly, the results of this study suggest that canine NK cells do not cause significant side effects such as GVHD and allogeneic NK cells can safely be used for cancer immunotherapy in dogs.


Subject(s)
CD3 Complex/metabolism , Graft vs Host Disease/therapy , Killer Cells, Natural/transplantation , Leukocytes, Mononuclear/immunology , Receptors, Antigen, T-Cell/metabolism , Transplantation, Heterologous/methods , Animals , Dogs , Graft vs Host Disease/immunology , Graft vs Host Disease/metabolism , Killer Cells, Natural/immunology , Mice , Mice, Inbred NOD , Mice, SCID
12.
Cytokine ; 148: 155599, 2021 12.
Article in English | MEDLINE | ID: mdl-34103211

ABSTRACT

Interleukin-15 (IL-15) is a pleiotropic cytokine that plays pivotal roles in innate and adaptive immunity. It is also a promising cytokine for treating cancer. Despite growing interest in its use as an immunotherapeutic, its safety and immunological effects in dogs have not been reported. In this study, healthy dogs were given recombinant canine IL-15 (rcIL-15) intravenously at a daily dose of 20 µg/kg for 8 days and monitored for 32 days to determine the safety and immunological effects of rcIL-15. The repeated administration of rcIL-15 was well tolerated, did not cause any serious side effects, and promoted the selective proliferation and activation of canine anti-cancer effector cells, including CD3+CD8+ cytotoxic T lymphocytes, CD3+CD5dimCD21-, and non-B/non-T NK cell populations, without stimulating Treg lymphocytes. The rcIL-15 injections also stimulated the expression of molecules and transcription factors associated with the activation and effector functions of NK cells, including CD16, NKG2D, NKp30, NKp44, NKp46, perforin, granzyme B, Ly49, T-bet, and Eomes. These results suggest that rcIL-15 might be a valuable therapeutic adjuvant to improve immunity against cancer in dogs.


Subject(s)
Interleukin-15/adverse effects , Interleukin-15/immunology , Recombinant Proteins/adverse effects , Recombinant Proteins/immunology , Animals , Antigens, CD/metabolism , Cell Proliferation/drug effects , Cytotoxicity, Immunologic/drug effects , Dogs/blood , Forkhead Transcription Factors/metabolism , Gene Expression Regulation/drug effects , Granzymes/metabolism , Humans , Interleukin-15/administration & dosage , Interleukin-15/toxicity , K562 Cells , Killer Cells, Natural/metabolism , Leukocyte Count , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/metabolism , Lymphocyte Subsets/drug effects , Lymphocyte Subsets/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Recombinant Proteins/administration & dosage , Recombinant Proteins/toxicity , T-Box Domain Proteins/metabolism
13.
Biomolecules ; 11(3)2021 02 24.
Article in English | MEDLINE | ID: mdl-33668179

ABSTRACT

Ocular disorders originating in the retina can result in a partial or total loss of vision, making drug delivery to the retina of vital importance. However, effectively delivering drugs to the retina remains a challenge for ophthalmologists due to various anatomical and physicochemical barriers in the eye. This review introduces diverse administration routes and the accordant pharmacokinetic profiles of ocular drugs to aid in the development of safe and efficient drug delivery systems to the retina with a focus on peptidomimetics as a growing class of retinal drugs, which have great therapeutic potential and a high degree of specificity. We also discuss the pharmacokinetic profiles of small molecule drugs due to their structural similarity to small peptidomimetics. Lastly, various formulation strategies are suggested to overcome pharmacokinetic hurdles such as solubility, retention time, enzymatic degradation, tissue targeting, and membrane permeability. This knowledge can be used to help design ocular delivery platforms for peptidomimetics, not only for the treatment of various retinal diseases, but also for the selection of potential peptidomimetic drug targets.


Subject(s)
Peptidomimetics , Retinal Diseases/metabolism , Animals , Drug Compounding , Drug Delivery Systems , Humans , Retina/metabolism
14.
Cell Rep Methods ; 1(8)2021 12 20.
Article in English | MEDLINE | ID: mdl-35128514

ABSTRACT

Using small molecule drugs to treat eye diseases carries benefits of specificity, scalability, and transportability, but their efficacy is significantly limited by a fast intraocular clearance rate. Ocular drug implants (ODIs) present a compelling means for the slow and sustained release of small molecule drugs inside the eye. However, methods are needed to inject small molecule ODIs into animals with small eyes, such as mice, which are the primary genetic models for most human ocular diseases. Consequently, it has not been possible to fully investigate efficacy and ocular pharmacokinetics of ODIs. Here, we present a robust, cost-effective, and minimally invasive method called "mouse implant intravitreal injection" (MI3) to deliver ODIs into mouse eyes. This method will expand ODI research to cover the breadth of human eye diseases modeled in mice.


Subject(s)
Drug Delivery Systems , Vitreous Body , Humans , Mice , Animals , Drug Implants/pharmacology , Intravitreal Injections
15.
Nat Commun ; 11(1): 6175, 2020 12 02.
Article in English | MEDLINE | ID: mdl-33268821

ABSTRACT

To elucidate the effects of neoadjuvant chemotherapy (NAC), we conduct whole transcriptome profiling coupled with histopathology analyses of a longitudinal breast cancer cohort of 146 patients including 110 pairs of serial tumor biopsies collected before treatment, after the first cycle of treatment and at the time of surgery. Here, we show that cytotoxic chemotherapies induce dynamic changes in the tumor immune microenvironment that vary by subtype and pathologic response. Just one cycle of treatment induces an immune stimulatory microenvironment harboring more tumor infiltrating lymphocytes (TILs) and up-regulation of inflammatory signatures predictive of response to anti-PD1 therapies while residual tumors are immune suppressed at end-of-treatment compared to the baseline. Increases in TILs and CD8+ T cell proportions in response to NAC are independently associated with pathologic complete response. Further, on-treatment immune response is more predictive of treatment outcome than immune features in paired baseline samples although these are strongly correlated.


Subject(s)
B7-H1 Antigen/genetics , Breast Neoplasms/drug therapy , Carcinoma, Ductal, Breast/drug therapy , Gene Expression Regulation, Neoplastic , Lymphocytes, Tumor-Infiltrating/drug effects , Neoadjuvant Therapy/methods , Anthracyclines/therapeutic use , B7-H1 Antigen/antagonists & inhibitors , B7-H1 Antigen/immunology , Breast Neoplasms/genetics , Breast Neoplasms/immunology , Breast Neoplasms/mortality , CD8-Positive T-Lymphocytes/drug effects , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/pathology , Carcinoma, Ductal, Breast/genetics , Carcinoma, Ductal, Breast/immunology , Carcinoma, Ductal, Breast/mortality , Cell Cycle Proteins/genetics , Cell Cycle Proteins/immunology , Cyclophosphamide/therapeutic use , Disease-Free Survival , Docetaxel/therapeutic use , Estrogen Receptor alpha/genetics , Estrogen Receptor alpha/immunology , Female , Gene Expression Profiling , Humans , Immunity, Innate , Interferon Regulatory Factors/genetics , Interferon Regulatory Factors/immunology , Longitudinal Studies , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes, Tumor-Infiltrating/pathology , Neoplasm, Residual , Receptor, ErbB-2/genetics , Receptor, ErbB-2/immunology , Trastuzumab/therapeutic use , Treatment Outcome , Tumor Microenvironment/drug effects , Tumor Microenvironment/genetics , Tumor Microenvironment/immunology
16.
Pharmaceutics ; 12(4)2020 Apr 08.
Article in English | MEDLINE | ID: mdl-32276508

ABSTRACT

Topical imageplication of epidermal growth fctor (EGF) has been used to accelerate diabetic foot ulcers but with limited efficacy. In this study, we selected a complex coacervate (EGF-Coa) composed of the low molecular weight gelatin type A and sodium alginate as a novel delivery system for EGF, based on encapsulation efficiency and protection of EGF from protease. EGF-Coa enhanced in vitro migration of keratinocytes and accelerated wound healing in streptozotocin-induced diabetic mice with increased granulation and re-epithelialization. While diabetic wound sites without treatment showed downward growth of hyperproliferative epidermis along the wound edges with poor matrix formation, EGF-Coa treatment recovered horizontal migration of epidermis over the newly deposited dermal matrix. EGF-Coa treatment also resulted in reduced levels of proinflammatory cytokines IL-1, IL-6, and THF-α. Freeze-dried coacervates packaged in aluminum pouches were stable for up to 4 months at 4 and 25 °C in terms of appearance, purity by RP-HPLC, and in vitro release profiles. There were significant physical and chemical changes in relative humidity above 33% or at 37 °C, suggesting the requirement for moisture-proof packaging and cold chain storage for long term stability. We propose low molecular weight gelatin type A and sodium alginate (LWGA-SA) coacervates as a novel EGF delivery system with enhanced efficacy for chronic wounds.

17.
Cancers (Basel) ; 12(3)2020 Mar 21.
Article in English | MEDLINE | ID: mdl-32245188

ABSTRACT

The chemotherapeutics sorafenib and regorafenib inhibit shedding of MHC class I-related chain A (MICA) from hepatocellular carcinoma (HCC) cells by suppressing a disintegrin and metalloprotease 9 (ADAM9). MICA is a ligand for natural killer (NK) group 2 member D (NKG2D) and is expressed on tumor cells to elicit attack by NK cells. This study measured ADAM9 mRNA levels in blood samples of advanced HCC patients (n = 10). In newly diagnosed patients (n = 5), the plasma ADAM9 mRNA level was significantly higher than that in healthy controls (3.001 versus 1.00, p < 0.05). Among four patients treated with nivolumab therapy, two patients with clinical response to nivolumab showed significant decreases in fold changes of serum ADAM9 mRNA level from 573.98 to 262.58 and from 323.88 to 85.52 (p < 0.05); however, two patients with no response to nivolumab did not. Using the Cancer Genome Atlas database, we found that higher expression of ADAM9 in tumor tissues was associated with poorer survival of HCC patients (log-rank p = 0.00039), while ADAM10 and ADAM17 exhibited no such association. In addition, ADAM9 expression showed a positive correlation with the expression of inhibitory checkpoint molecules. This study, though small in sample size, clearly suggested that ADAM9 mRNA might serve as biomarker predicting clinical response and that the ADAM9-MICA-NKG2D system can be a good therapeutic target for HCC immunotherapy. Future studies are warranted to validate these findings.

18.
BMC Vet Res ; 15(1): 339, 2019 Oct 14.
Article in English | MEDLINE | ID: mdl-31610784

ABSTRACT

BACKGROUND: The antibody-dependent cellular cytotoxicity (ADCC) is a cell-mediated immune defense mechanism in which effector immune cells actively lyse antibody-coated target cells. The ADCC of tumor cells is employed in the treatment of various cancers overexpressing unique antigens, and only natural killer (NK) cells are known to be major effectors of antibody mediated ADCC activity. Canine NK cells are still defined as non-B, non-T large granular lymphocytes because of the lack of information regarding the NK cell-restricted specific marker in dogs, and it has never been demonstrated that canine NK cells have ADCC ability against tumor cells. In the present study, we investigated whether canine non-B, non-T NK cells have ADCC ability against target antibody-coated tumor cells, using cetuximab and trastuzumab, the only human antibodies reported binding to canine cancer cells. RESULTS: Activated canine non-B, non-T NK cells (CD3-CD21-CD5-TCRαß-TCRγδ-) for 13~17 days ex vivo showed ADCC ability against trastuzumab- or cetuximab-coated target tumor cells expressing various levels of human epidermal growth factor receptor 2 (HER-2) and epidermal growth factor receptor (EGFR). Trastuzumab and cetuximab induced significant ADCC responses of canine NK cells even in CMT-U334 and CF41.Mg cells expressing low levels of HER-2 and/or EGFR, as well as in SKBR3 and DU145 cells overexpressing HER-2 and/or EGFR. The trastuzumab-mediated ADCC activity of NK cells was significantly enhanced by treatment with rcIL-21. CONCLUSIONS: The results of this study suggest that canine non-B, non-T NK lymphocytes have a potential ADCC function and that combinational strategies of monoclonal antibodies with either cytokines, which activate NK cells in vivo, or adoptive transfer of NK cells may be a feasible method for amplifying the efficacy of immunotherapy against malignant cancers even with very low expression of target molecules in dogs.


Subject(s)
Antibody-Dependent Cell Cytotoxicity , Killer Cells, Natural/immunology , Neoplasms/drug therapy , Animals , Antibodies, Monoclonal/immunology , Antineoplastic Agents, Immunological/pharmacology , Cell Line, Tumor , Cetuximab/pharmacology , Dogs , ErbB Receptors/antagonists & inhibitors , Humans , Receptor, ErbB-2/antagonists & inhibitors , Trastuzumab/pharmacology
19.
Adv Healthc Mater ; 8(14): e1900275, 2019 07.
Article in English | MEDLINE | ID: mdl-31091015

ABSTRACT

Chitosan-catechol, inspired from mussel-adhesive-proteins, is characterized by the formation of an adhesive membrane complex through instant bonding with serum proteins not found in chitosan. Using this intrinsic property, chitosan-catechol is widely applied for hemostatic needles, general hemostatic materials, nanoparticle composites, and 3D printing. Despite its versatility, the practical use of chitosan-catechol in the clinic is limited due to its undesired immune responses. Herein, a catechol-conjugated glycol chitosan is proposed as an alternative hemostatic hydrogel with negligible immune responses enabling the replacement of chitosan-catechol. Comparative cellular toxicity and in vivo skin irritation between chitosan-catechol and glycol chitosan-catechol are evaluated. Their immune responses are also assessed using histological analysis after subcutaneous implantation into mice. The results show that glycol chitosan-catechol significantly attenuates the immune response compared with chitosan-catechol; this finding is likely due to the antibiofouling effect of ethylene glycol groups and the reduced adhesion of immune cells. Finally, the tissue adhesion and hemostatic ability of glycol chitosan-catechol hydrogels reveal that these ethylene glycol groups do not dramatically modify the adhesiveness and hemostatic ability compared with nonglycol chitosan-catechol. This study suggests that glycol chitosan-catechol can be a promising alternative to chitosan-catechol in various biomedical fields such as hemostatic agents.


Subject(s)
Adhesives/toxicity , Bivalvia/physiology , Chitosan/toxicity , Adhesiveness , Animals , Cell Line , Cell Survival/drug effects , Chitosan/chemistry , Hemostatics/pharmacology , Hydrogels/chemistry , Mice , Rats , Skin/drug effects , Skin/immunology
20.
J Control Release ; 307: 413-422, 2019 08 10.
Article in English | MEDLINE | ID: mdl-31121276

ABSTRACT

Catechin exhibits various pharmacological effects, yet its poor aqueous solubility limits its clinical use. Here, we investigate a facile catechin solubilization method via spontaneous hydrogen bonding between catechin and poly(ethylene glycol) (PEG). The method is extremely simple in that mixing PEG with catechin followed by lyophilization completely converts insoluble catechin to soluble PEG/catechin nanoscale complexes. This solubilized catechin formulation is useful for preparing eyedrop medicine, and we demonstrate that the solubilized catechin exhibits therapeutic effect upon dry eye diseases.


Subject(s)
Catechin/administration & dosage , Dry Eye Syndromes/drug therapy , Nanoparticles/administration & dosage , Ophthalmic Solutions/administration & dosage , Polyethylene Glycols/administration & dosage , Animals , Catechin/chemistry , Freeze Drying , Hydrogen Bonding , Male , Mice , Nanoparticles/chemistry , Polyethylene Glycols/chemistry , Solubility
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