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1.
Sci Rep ; 14(1): 6738, 2024 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-38509125

RESUMEN

Hypoxia-Inducible Factor-1α (HIF-1α) has presented a new direction for ischemic preconditioning of surgical flaps to promote their survival. In a previous study, we demonstrated the effectiveness of HIF-1a DNA plasmids in this application. In this study, to avoid complications associated with plasmid use, we sought to express HIF-1α through mRNA transfection and determine its biological activity by measuring the upregulation of downstream angiogenic genes. We transfected six different HIF-1a mRNAs-one predominant, three variant, and two novel mutant isoforms-into primary human dermal fibroblasts using Lipofectamine, and assessed mRNA levels using RT-qPCR. At all time points examined after transfection (3, 6, and 10 h), the levels of HIF-1α transcript were significantly higher in all HIF-1α transfected cells relative to the control (all p < 0.05, unpaired Student's T-test). Importantly, the expression of HIF-1α transcription response genes (VEGF, ANG-1, PGF, FLT1, and EDN1) was significantly higher in the cells transfected with all isoforms than with the control at six and/or ten hours post-transfection. All isoforms were transfected successfully into human fibroblast cells, resulting in the rapid upregulation of all five downstream angiogenic targets tested. These findings support the potential use of HIF-1α mRNA for protecting ischemic dermal flaps.


Asunto(s)
Subunidad alfa del Factor 1 Inducible por Hipoxia , Factor A de Crecimiento Endotelial Vascular , Humanos , Factor A de Crecimiento Endotelial Vascular/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , ARN Mensajero/metabolismo , Transfección , Péptidos y Proteínas de Señalización Intercelular/genética , Isoformas de Proteínas/genética
2.
Int J Mol Sci ; 24(18)2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37762397

RESUMEN

Wound therapies involving gene delivery to the skin have significant potential due to the advantage and ease of local treatment. However, choosing the appropriate vector to enable successful gene expression while also ensuring that the treatment's immediate material components are conducive to healing itself is critical. In this study, we utilized a particulate formulation of the polymer chitosan (chitosan particles, CPs) as a non-viral vector for the delivery of a plasmid encoding human CA5-HIF-1α, a degradation resistant form of HIF-1α, to enhance wound healing. We also compared the angiogenic potential of our treatment (HIF/CPs) to that of chitosan particles containing only the plasmid backbone (bb/CPs) and the chitosan particle vector alone (CPs). Our results indicate that chitosan particles exert angiogenic effects that are enhanced with the human CA5-HIF-1α-encoded plasmid. Moreover, HIF/CPs enhanced wound healing in diabetic db/db mice (p < 0.01), and healed tissue was found to contain a significantly increased number of blood vessels compared to bb/CPs (p < 0.01), CPs (p < 0.05) and no-treatment groups (p < 0.01). Thus, this study represents a method of gene delivery to the skin that utilizes an inherently pro-wound-healing polymer as a vector for plasmid DNA that has broad application for the expression of other therapeutic genes.

4.
Adv Healthc Mater ; 12(26): e2300879, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37335811

RESUMEN

Extracellular vesicles (EVs) derived from mesenchymal stem/stromal cells (MSCs) have recently been explored in clinical trials for treatment of diseases with complex pathophysiologies. However, production of MSC EVs is currently hampered by donor-specific characteristics and limited ex vivo expansion capabilities before decreased potency, thus restricting their potential as a scalable and reproducible therapeutic. Induced pluripotent stem cells (iPSCs) represent a self-renewing source for obtaining differentiated iPSC-derived MSCs (iMSCs), circumventing both scalability and donor variability concerns for therapeutic EV production. Thus, it is initially sought to evaluate the therapeutic potential of iMSC EVs. Interestingly, while utilizing undifferentiated iPSC EVs as a control, it is found that their vascularization bioactivity is similar and their anti-inflammatory bioactivity is superior to donor-matched iMSC EVs in cell-based assays. To supplement this initial in vitro bioactivity screen, a diabetic wound healing mouse model where both the pro-vascularization and anti-inflammatory activity of these EVs would be beneficial is employed. In this in vivo model, iPSC EVs more effectively mediate inflammation resolution within the wound bed. Combined with the lack of additional differentiation steps required for iMSC generation, these results support the use of undifferentiated iPSCs as a source for therapeutic EV production with respect to both scalability and efficacy.


Asunto(s)
Diabetes Mellitus , Vesículas Extracelulares , Células Madre Pluripotentes Inducidas , Ratones , Animales , Diferenciación Celular/fisiología , Antiinflamatorios , Cicatrización de Heridas
5.
bioRxiv ; 2023 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-36993554

RESUMEN

Extracellular vesicles (EVs) derived from mesenchymal stem/stromal cells (MSCs) have recently been widely explored in clinical trials for treatment of diseases with complex pathophysiology. However, production of MSC EVs is currently hampered by donor-specific characteristics and limited ex vivo expansion capabilities before decreased potency, thus restricting their potential as a scalable and reproducible therapeutic. Induced pluripotent stem cells (iPSCs) represent a self-renewing source for obtaining differentiated iPSC-derived MSCs (iMSCs), circumventing both scalability and donor variability concerns for therapeutic EV production. Thus, we initially sought to evaluate the therapeutic potential of iMSC EVs. Interestingly, while utilizing undifferentiated iPSC EVs as a control, we found that their vascularization bioactivity was similar and their anti-inflammatory bioactivity was superior to donor-matched iMSC EVs in cell-based assays. To supplement this initial in vitro bioactivity screen, we employed a diabetic wound healing mouse model where both the pro-vascularization and anti-inflammatory activity of these EVs would be beneficial. In this in vivo model, iPSC EVs more effectively mediated inflammation resolution within the wound bed. Combined with the lack of additional differentiation steps required for iMSC generation, these results support the use of undifferentiated iPSCs as a source for therapeutic EV production with respect to both scalability and efficacy.

6.
Adv Healthc Mater ; 12(20): e2300584, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36930747

RESUMEN

Extracellular vesicles (EVs) are implicated as promising therapeutics and drug delivery vehicles in various diseases. However, successful clinical translation will depend on the development of scalable biomanufacturing approaches, especially due to the documented low levels of intrinsic EV-associated cargo that may necessitate repeated doses to achieve clinical benefit in certain applications. Thus, here the effects of a 3D-printed scaffold-perfusion bioreactor system are assessed on the production and bioactivity of EVs secreted from bone marrow-derived mesenchymal stem cells (MSCs), a cell type widely implicated in generating EVs with therapeutic potential. The results indicate that perfusion bioreactor culture induces an ≈40-80-fold increase (depending on measurement method) in MSC EV production compared to conventional cell culture. Additionally, MSC EVs generated using the perfusion bioreactor system significantly improve wound healing in a diabetic mouse model, with increased CD31+ staining in wound bed tissue compared to animals treated with flask cell culture-generated MSC EVs. Overall, this study establishes a promising solution to a major EV translational bottleneck, with the capacity for tunability for specific applications and general improvement alongside advancements in 3D-printing technologies.


Asunto(s)
Vesículas Extracelulares , Células Madre Mesenquimatosas , Animales , Ratones , Vesículas Extracelulares/metabolismo , Reactores Biológicos , Perfusión , Impresión Tridimensional
7.
Cytotherapy ; 25(5): 502-509, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36513574

RESUMEN

BACKGROUND AIMS: As evidenced by ongoing clinical trials and increased activity in the commercial sector, extracellular vesicle (EV)-based therapies have begun the transition from bench to bedside. As this progression continues, one critical aspect of EV clinical translation is understanding the effects of storage and transport conditions. Several studies have assessed the impact of storage on EV characteristics such as morphology, uptake and component content, but effects of storage duration and temperature on EV functional bioactivity and, especially, loaded cargo are rarely reported. METHODS: The authors assessed EV outcomes following storage at different temperatures (room temperature, 4°C, -20°C, -80°C) for various durations as well as after lyophilization. RESULTS: Mesenchymal stromal cell (MSC) EVs were observed to retain key aspects of their bioactivity (pro-vascularization, anti-inflammation) for up to 4-6 weeks at -20°C and -80°C and after lyophilization. Furthermore, via in vitro assays and an in vivo wound healing model, these same storage conditions were also demonstrated to enable preservation of the functionality of loaded microRNA and long non-coding RNA cargo in MSC EVs. CONCLUSIONS: These findings extend the current understanding of how EV therapeutic potential is impacted by storage conditions and may inform best practices for handling and storing MSC EVs for both basic research and translational purposes.


Asunto(s)
Vesículas Extracelulares , Células Madre Mesenquimatosas , MicroARNs , Cicatrización de Heridas
8.
eGastroenterology ; 1(2)2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38188186

RESUMEN

Worldwide, gastric cancer results in significant morbidity and mortality. Ten per cent of patients with gastric cancer have a strong family history of the disease. CDH1 (E-cadherin) has been identified as a key gene whose mutation leads to hereditary diffuse gastric cancer. We overviewed 33 articles with prophylactic total gastrectomy and assessed the outcomes and benefits. Families with mutations in CDH1 may benefit from early prophylactic total gastrectomy. Dr Mark Duncan has applied his experience as a high-volume gastric cancer surgeon to treat not only individual patients, but several generations of patients within a family. This use of prophylactic total gastrectomy is well tolerated by patients and prevents the future development of gastric cancer.

9.
eGastroenterology ; 1(2)2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38292831

RESUMEN

The History Maker paper focuses on the extraordinary revolution that dramatically improved the surgical results for the Whipple procedure (pancreaticoduodenectomy) in the 1980s and identifies Dr. Cameron as the leader of this revolution, who reported a mortality rate of approximately 1%. The revolutionary reduction of postoperative mortality for the Whipple procedure was achieved by adherence to gentle and precise Halstedian surgical techniques with adequate drainage of pancreatico-jejunal anastomosis with closed-suction silastic drains, along with the development of high-volume surgeons and hospitals. Excellent teamwork in patient care, including but not limited to preoperative evaluation by multidisciplinary teams, intraoperative communication between surgeons and anaesthesiologists, and postoperative management, contributed to a successful Whipple procedure.

10.
J Surg Res ; 278: 433-444, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35667884

RESUMEN

INTRODUCTION: Esophageal cancer is an aggressive malignancy with high mortality. Optimal treatment of esophageal cancer remains an elusive goal. Ribonucleic acid (RNA) interference is a novel potential targeted approach to treat esophageal cancer. Targeting oncogenes that can alter critical cellular functions with silencing RNA molecules is a promising approach. The silencing of specific oncogenes in esophageal cancer cells in the experimental setting has been shown to decrease the expression of oncogenic proteins. This has resulted in cell apoptosis, reduction in cell proliferation, reduced invasion, migration, epithelial-mesenchymal transition, decrease in tumor angiogenesis and metastasis, and overcoming drug resistance. The Hedgehog (Hh) signaling pathway has been shown to be involved in esophageal adenocarcinoma formation in a reflux animal model. In addition to Hh, we will focus on other targets with clinical potential in the treatment of esophageal cancer. MATERIALS AND METHODS: We searched for articles published from 2005 to August 2020 that studied the siRNA effects on inhibiting esophageal cancer formation in experimental settings. We used combinations of the following terms for searching: "esophageal cancer," "RNA interference," "small interfering RNA," "siRNA," "silencing RNA," "Smoothened (Smo)," "Gli," "Bcl-2," "Bcl-XL," "Bcl-W,″ "Mcl-1," "Bfl-1," "STAT3,"and "Hypoxia inducible factor (HIF)". A total of 21 relevant articles were found. RESULTS AND CONCLUSIONS: Several proto-oncogenes/oncogenes including Hh pathway mediators, glioma-associated oncogene homolog 1 (Gli-1), Smoothened (Smo), and antiapoptotic Bcl-2 have potential as targets for silencing RNA in the treatment of esophageal cancer.


Asunto(s)
Neoplasias Esofágicas , Proteínas Hedgehog , Animales , Línea Celular Tumoral , Proliferación Celular , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/terapia , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , ARN Interferente Pequeño/metabolismo , Proteína con Dedos de Zinc GLI1/genética
11.
Adv Healthc Mater ; 11(5): e2002070, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-33870645

RESUMEN

Chronic wounds remain a substantial source of morbidity worldwide. An emergent approach that may be well-suited to induce the complex, multicellular processes such as angiogenesis that are required for wound repair is the use of extracellular vesicles (EVs). EVs contain a wide variety of proteins and nucleic acids that enable multifactorial signaling. Here, the capability of EVs is leveraged to be engineered via producer cell modification to investigate the therapeutic potential of EVs from mesenchymal stem/stromal cells (MSCs) transfected to overexpress long non-coding RNA HOX transcript antisense RNA (HOTAIR). HOTAIR is previously shown by the authors' group to be critical in mediating angiogenic effects of endothelial cell EVs, and MSCs are chosen as EV producer cells for this study due to their widely reported intrinsic angiogenic properties. The results indicate that MSCs overexpressing HOTAIR (HOTAIR-MSCs) produce EVs with increased HOTAIR content that promote angiogenesis and wound healing in diabetic (db/db) mice. Further, endothelial cells exposed to HOTAIR-MSC EVs exhibit increased HOTAIR content correlated with upregulation of the angiogenic protein vascular endothelial growth factor. Thus, this study supports EV-mediated HOTAIR delivery as a strategy for further exploration toward healing of chronic wounds.


Asunto(s)
Vesículas Extracelulares , Células Madre Mesenquimatosas , ARN Largo no Codificante , Animales , Células Endoteliales/metabolismo , Vesículas Extracelulares/metabolismo , Células Madre Mesenquimatosas/metabolismo , Ratones , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Cicatrización de Heridas
12.
Ann Surg ; 273(6): e206-e213, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-31290765

RESUMEN

OBJECTIVE: The aim of the study was to investigate whether inhibition of Sonic Hedgehog (SHH) pathway would prevent progression of Barrett's Esophagus (BE) to esophageal adenocarcinoma. BACKGROUND: The hedgehog signaling pathway is a leading candidate as a molecular mediator of BE and esophageal adenocarcinoma (EAC). Repurposed use of existing off-patent, safe and tolerable drugs that can inhibit hedgehog, such as itraconazole, could prevent progression of BE to EAC. METHODS: The efficacy of itraconazole was investigated using a surgical rat reflux model of Barrett's Metaplasia (BM). Weekly intraperitoneal injections of saline (control group) or itraconazole (treatment group; 200 mg/kg) were started at 24 weeks postsurgery. Esophageal tissue was harvested at 40 weeks. The role of the Hh pathway was also evaluated clinically. Esophageal tissue was harvested after 40 weeks for pathological examination and evaluation of the SHH pathway by immunohistochemistry. RESULTS: BM was present in control animals 29 of 31 (93%) versus itraconazole 22 of 24 (91%). EAC was significantly lower in itraconazole 2 of 24 (8%) versus control 10 of 31 (32%), respectively (P = 0.033). Esophageal SHH levels were lower in itraconazole vs control (P = 0.12). In esophageal tissue from humans with recurrent or persistent dysplastic BE within 24 months of ablative treatment, strong SHH and Indian Hedgehog expression occurred in distal BE versus proximal squamous epithelium, odds ratio = 6.1 (95% confidence interval: 1.6, 23.4) and odds ratio = 6.4 (95% confidence interval: 1.2, 32.8), respectively. CONCLUSION: Itraconazole significantly decreases EAC development and SHH expression in a preclinical animal model of BM. In humans, BE tissue expresses higher SHH, Indian Hedgehog, and bone morphogenic protein levels than normal squamous esophageal epithelium.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/etiología , Esófago de Barrett/complicaciones , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/etiología , Proteínas Hedgehog/antagonistas & inhibidores , Itraconazol/farmacología , Itraconazol/uso terapéutico , Adenocarcinoma/patología , Animales , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Neoplasias Esofágicas/patología , Masculino , Invasividad Neoplásica , Ratas , Ratas Sprague-Dawley
13.
Gene Ther ; 28(6): 319-328, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33024315

RESUMEN

Ischemic necrosis of surgical flaps after reconstruction is a major clinical problem. Hypoxia-inducible factor-1α (HIF-1α) is considered the master regulator of the adaptive response to hypoxia. Among its many properties, it regulates the expression of genes encoding angiogenic growth factors, which have a short half-life in vivo. To achieve a continuous application of the therapeutic, we utilized DNA plasmid delivery. Transcription of the DNA plasmid confirmed by qRT-PCR showed significantly increased mRNA for HIF-1α in the transfected tissue compared to saline control tissue. Rats were preconditioned by injecting with either HIF-1α DNA plasmid or saline intradermally in the designated flap region on each flank. Seven days after preconditioning, each rat had two isolated pedicle flaps raised with a sterile silicone sheet implanted between the skin flap and muscle layer. The flaps preconditioned with HIF-1α DNA plasmid had significantly less necrotic area. Angiogenesis measured by CD31 staining showed a significant increase in the number of vessels per high powered field in the HIF-1α group (p < 0.05). Our findings offer a potential therapeutic strategy for significantly promoting the viability of surgical pedicle flaps by ischemic preconditioning with HIF-1α DNA plasmid.


Asunto(s)
Subunidad alfa del Factor 1 Inducible por Hipoxia , Colgajos Quirúrgicos , Animales , ADN , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Plásmidos/genética , Ratas , Ratas Sprague-Dawley , Supervivencia Tisular
14.
Bioeng Transl Med ; 5(3): e10172, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33005738

RESUMEN

Both extracellular vesicles (EVs) and long noncoding RNAs (lncRNAs) have been increasingly investigated as biomarkers, pathophysiological mediators, and potential therapeutics. While these two entities have often been studied separately, there are increasing reports of EV-associated lncRNA activity in processes such as oncogenesis as well as tissue repair and regeneration. Given the powerful nature and emerging translational impact of other noncoding RNAs such as microRNA (miRNA) and small interfering RNA, lncRNA therapeutics may represent a new frontier. While EVs are natural vehicles that transport and protect lncRNAs physiologically, they can also be engineered for enhanced cargo loading and therapeutic properties. In this review, we will summarize the activity of lncRNAs relevant to both tissue repair and cancer treatment and discuss the role of EVs in enabling the potential of lncRNA therapeutics.

15.
J Surg Res ; 247: 438-444, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31685251

RESUMEN

BACKGROUND: Gastric cancer is a leading cause of cancer-related death across the world. A subset of gastric cancers demonstrates an inherited genetic predisposition. Individuals with germline mutations in the CDH1 gene incur a lifetime risk for diffuse gastric cancer and benefit from prophylactic gastrectomy. The results for this operative intervention remain relatively undescribed in the literature, despite guidelines supporting its use. METHODS: We present a single-institution series of patients with confirmed CDH1 mutations who underwent gastrectomy. We describe their presenting symptoms, preoperative screening, clinicopathologic features, and outcomes. Focal outcomes of interest are weight loss and postoperative morbidity. RESULTS: Between 2010 and 2018, ten patients with a confirmed CDH1 mutation underwent total gastrectomy with intestinal pouch reconstruction at our institution. Two patients had clinical gastric cancer at the time of their operation at 21 and 60 y of age. Eight patients had prophylactic gastrectomy. All prophylactic patients had undergone prior endoscopic screening without detection of cancer; however, three had occult gastric cancer on pathological examination. Median weight loss after gastrectomy was 10 kg at 6 mo and 11 kg at 1 y. Postoperative morbidity was limited to one anastomotic leak, one hematoma, and one case of pneumonia. All patients remain disease-free with median follow-up of 19 mo. CONCLUSIONS: Total gastrectomy for patients with a CDH1 mutation is a cancer-preventing operation for a high-risk population. For this series, jejunal pouch reconstruction was performed with encouragingly low postoperative morbidity, weight loss, and good subjective function.


Asunto(s)
Antígenos CD/genética , Cadherinas/genética , Gastrectomía/métodos , Predisposición Genética a la Enfermedad , Procedimientos Quirúrgicos Profilácticos/métodos , Neoplasias Gástricas/cirugía , Adulto , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Gastrectomía/efectos adversos , Gastroscopía , Mutación de Línea Germinal , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estómago/diagnóstico por imagen , Estómago/cirugía , Neoplasias Gástricas/epidemiología , Neoplasias Gástricas/genética , Neoplasias Gástricas/prevención & control , Pérdida de Peso , Adulto Joven
16.
Anticancer Res ; 39(10): 5565-5572, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31570451

RESUMEN

BACKGROUND/AIM: The aim of the study was to evaluate the status of extravasated platelet activation (EPA) surrounding podoplanin (PDPN)-positive cancer-associated fibroblasts (CAFs) in pancreatic cancer stroma by neoadjuvant chemotherapy. PATIENTS AND METHODS: A total of 74 patients were enrolled in this study. We investigated CD42b and PDPN expression in the groups of untreated, gemcitabine (GEM) alone, GEM plus S-1 (GS) and GEM plus nab-paclitaxel (GnP). RESULTS: CD42b expression in surrounding CAFs was observed in 58% patients. CD42b expression was significantly correlated with PDPN expression. CD42b-positive cases were significantly lower in the group treated with GnP than in the untreated group and groups treated with GEM alone or GS. PDPN expression was reduced in the GnP group, as revealed by markedly disorganized collagen and a low density of PDPN-positive fibroblasts. There was a significantly lower CD42b expression and fewer PDPN-positive fibroblasts in the GnP group than in untreated, GEM alone, and GS groups, but there was no significant difference between the latter three groups. CONCLUSION: There is a significant association between EPA and PDPN-positive CAFs in pancreatic cancer stroma. Our data suggest that the GnP regimen decreases EPA through PDPN-positive CAF depletion.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Fibroblastos Asociados al Cáncer/efectos de los fármacos , Glicoproteínas de Membrana/metabolismo , Neoplasias Pancreáticas/tratamiento farmacológico , Activación Plaquetaria/efectos de los fármacos , Adulto , Anciano , Anciano de 80 o más Años , Albúminas/uso terapéutico , Fibroblastos Asociados al Cáncer/metabolismo , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapéutico , Combinación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante/métodos , Ácido Oxónico/uso terapéutico , Paclitaxel/uso terapéutico , Neoplasias Pancreáticas/metabolismo , Complejo GPIb-IX de Glicoproteína Plaquetaria/metabolismo , Tegafur/uso terapéutico , Gemcitabina
17.
Transl Oncol ; 12(11): 1432-1441, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31401336

RESUMEN

Krüppel-like Factor 5 (KLF5) is a zinc-finger transcription factor associated with cell cycle progression and cell survival. KLF5 plays a key role in mammalian intestinal epithelium development and maintenance, expressed at high levels in basal proliferating cells and low levels in terminally differentiated cells. Considering Barrett's esophagus (BE) and esophageal adenocarcinoma's (EAC) histopathological similarities to intestinal epithelium, we sought to determine KLF5's role in BE and EAC, as well as KLF5's possible connection to the sonic hedgehog (SHH) pathway which is highly active in BE and EAC development. Low levels of KLF5 mRNA were found in BE cell lines and tissue- similar to what has been reported in differentiated intestinal epithelium. In contrast, higher KLF5 levels were observed in EAC cells and tissues. KLF5 knockdown in EAC cells caused significant decreases in cell migration, proliferation, and EAC-associated gene expression. Moreover, KLF5 knockdown led to decreased SHH signaling. These results suggest that KLF5 is connected to the SHH pathway in BE and EAC and may represent a potential drug target in EAC; further studies are now indicated to verify these findings and elucidate underlying mechanisms involved.

18.
Adv Healthc Mater ; 7(14): e1800016, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29663707

RESUMEN

Skin and skin appendages protect the body from harmful environment and prevent internal organs from dehydration. Superficial epidermal wounds usually heal without scarring, however, deep dermal wound healing commonly ends up with nonfunctioning scar formation with substantial loss of skin appendage. Wound healing is one of the most complex dynamic biological processes, during which a cascade of biomolecules combine with stem cell influx and matrix synthesis and synergistically contribute to wound healing at all levels. Although many approaches have been investigated to restore complete skin, the clinically effective therapy is still unavailable and the regeneration of perfect skin still remains a significant challenge. The complete mechanism behind scarless skin regeneration still requires further investigation. Fortunately, recent advancement in regenerative medicine empowers us more than ever to restore tissue in a regenerative manner. Many studies have elucidated and reviewed the contribution of stem cells and growth factors to scarless wound healing. This article focuses on recent advances in scarless wound healing, especially strategies to engineer pro-regenerative scaffolds to restore damaged skin in a regenerative manner.


Asunto(s)
Medicina Regenerativa/métodos , Animales , Humanos , Hidrogeles/química , Macrófagos/metabolismo , Neovascularización Fisiológica/fisiología , Cicatrización de Heridas/fisiología
19.
Eplasty ; 18: e14, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29619144

RESUMEN

Introduction: Excessive bleeding is a complication of wound debridement in patients receiving anticoagulation treatment. Chitosan is a linear, positively charged polysaccharide that has potential as a hemostatic topical dressing. This study examined the hemostatic efficacy of the chitosan based Opticell dressing (Medline Industries, Chicago, Ill) in heparinized rats with excisional wounds mimicking debridement. Methods: Three paired 12-mm excisional wounds were created on the dorsum of 600-g Sprague-Dawley rats 2 hours after intraperitoneal injection of heparin 800 IU/kg. Opticell or gauze dressings were applied with 3 seconds of gentle pressure. Results:Total Bleeding: The dressings were left in place until cessation of bleeding. Ten minutes was enough time for complete bleeding cessation in both groups. Gauze and Opticell were weighed before and after bleeding cessation, with the difference representing blood loss. Total blood loss was 627 ± 47 mg/10 min with the standard gauze, but 247 ± 47 mg/10 min with Opticell (P = .002 Mann-Whitney). N = 6 wounds per group. Rate of Bleeding: Gauze and Opticell dressings were removed and instantly replaced with 3 seconds of gentle pressure every minute until bleeding cessation. The removed dressings were weighed before and after application. There was less bleeding in the Opticell group at minutes 1, 2, and 3. Gauze: 183 ± 40, 140 ± 30, and 109 ± 15 mg/min vs Opticell: 91 ± 17, 54 ± 8, and 57 ± 11 mg/min). Analysis of variance, Tukey's test, P < .05. N = 12 wounds per group. Conclusion: Topical application of Opticell dressing with chitosan has hemostatic effects that could be a useful tool to control bleeding associated with wound debridement.

20.
Surgery ; 2018 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-29576309

RESUMEN

BACKGROUND: Prostaglandin E2 is one of the potential products that promotes development of tumors and also is a strong inducer of M2 phenotype macrophages, which contribute to tumor development in the immunosuppressed microenvironment. Hangeshashinto (TJ-14), a Japanese traditional medicine (Kampo medicine), has been reported to be effective in preventing chemotherapy-induced oral mucositis through the reduction of prostaglandin E2. We previously developed a surgical rat reflux model of esophageal cancer and used this well-established animal model to investigate the action of TJ-14 in preventing esophageal cancer. We also assessed the effect of TJ-14 on the downregulation of prostaglandin E2 production, utilizing esophageal squamous cell carcinoma cell line exposed to bile acid. METHODS: An end-to-side esophagojejunostomy was performed for the reflux model. A daily oral diet was subsequently administered, consisting of either diet-incorporated TJ-14 or standard diet as a control group. The rats were killed at 40 weeks after surgery. The incidence of esophageal cancer, Barrett's metaplasia, and proliferative hyperplasia were assessed histologically. CD163, a M2 phenotype macrophage marker, was assessed with immunohistochemistry. Prostaglandin E2 enzyme immunoassay and lactate dehydrogenase assay were performed on chenodeoxycholic acid or gastroesophageal reflux contents exposed to esophageal squamous cell carcinoma cell line. RESULTS: Sixty-seven percent of the controls (n = 12) developed esophageal cancer, but animals that received TJ-14 (n = 10) had a cancer incidence of 10% (P=.007). Barrett's metaplasia was found in 83% of the rats in the control group and 50% of the rats in the TJ-14 indicating a protective tendency of TJ-14 (P=.095). All of the rats developed proliferative hyperplasia. The number of M2 phenotype macrophage were significantly decreased in the TJ-14 group compared to the control group in both Barrett's metaplasia and esophageal cancer lesions. TJ-14 inhibited chenodeoxycholic acid or gastroesophageal reflux content-induced prostaglandin E2 production in esophageal squamous cell carcinoma cell. CONCLUSION: TJ-14 reduced the incidence of reflux-induced esophageal cancer and the infiltration of M2 macrophages in a surgical rat model or suppressed prostaglandin E2 production in esophageal squamous cell carcinoma cell. Further investigation is required regarding the potential clinical use of TJ-14 as an esophageal cancer chemopreventive agent.

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