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1.
J Fr Ophtalmol ; 45(7): 700-709, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35779968

RESUMEN

PURPOSE: To utilize data mining for analysis of corneal transplantations (CT) in Florida from 2005-2014, segmented by demographics, geography, and transplantation technique. METHODS: A retrospective, database study was performed utilizing data queried from the Healthcare and Cost Utilization Project using Current Procedural Terminology codes for lamellar keratoplasty (ALK), endothelial keratoplasty (EK), and penetrating keratoplasty (PKP). Payer status, ethnic group, age, gender, and geography (urban versus rural) was extracted from each surgical encounter and reconfigured to provide a "clean", congruous dataset for statistical analysis. This Institutional Review Board-approved study did not utilize identifiable patient information; thus, individual informed consent was not required. RESULTS: From 2005-2014, CT (n=28,607) represented less than 1% of the total ambulatory surgeries (n=12,695,932) performed in Florida. EK volume increased while PKP and ALK volume decreased, year-over-year. Statistical significance was found between transplantation technique by sex (P<0.001) and ethnic group (P<0.001). The largest sex discrepancy was EK (59% female, 41% male). White patients underwent relatively fewer PKP than EK (71% vs. 83% of totals), while Black patients underwent relatively more PKP than EK (14% vs 6% of totals). Statistical significance was found between techniques by payer (P<0.001). Medicare was the most common payer for all techniques, but ALK and PKP had higher percentages of private insurance and self-pay. No statistical significance was found between techniques by geographic location. Corneal edema (22.4%), endothelial dystrophy (17.5%), and bullous keratopathy (10.9%) were erroneously coded as indications for ALK. Corneal scars (2.5%) and corneal opacity (1.7%) were erroneously coded as indications for EK. CONCLUSIONS: CT rates in Florida appear to overrepresent the female sex and underrepresent ethnic minorities, with propensities between PKP and African Americans, EK and female patients, and EK and Medicare reimbursement. Our study further confirms the utility of data mining for providing efficient, detailed, and practical insights into ophthalmology procedures, while highlighting the intrinsic challenges of large datasets.


Asunto(s)
Enfermedades de la Córnea , Trasplante de Córnea , Anciano , Algoritmos , Enfermedades de la Córnea/epidemiología , Enfermedades de la Córnea/cirugía , Trasplante de Córnea/métodos , Minería de Datos , Femenino , Humanos , Queratoplastia Penetrante/métodos , Masculino , Medicare , Proteínas Tirosina Quinasas Receptoras , Estudios Retrospectivos , Estados Unidos
2.
Regen Ther ; 17: 38-50, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33869685

RESUMEN

Intratumoral heterogeneity is tightly associated with the failure of anticancer treatment modalities including conventional chemotherapy, radiation therapy, and molecularly targeted therapy. Such heterogeneity is generated in an evolutionary manner not only as a result of genetic alterations but also by the presence of cancer stem cells (CSCs). CSCs are proposed to exist at the top of a tumor cell hierarchy and are undifferentiated tumor cells that manifest enhanced tumorigenic and metastatic potential, self-renewal capacity, and therapeutic resistance. Properties that contribute to the robustness of CSCs include the abilities to withstand redox stress, to rapidly repair damaged DNA, to adapt to a hyperinflammatory or hyponutritious tumor microenvironment, and to expel anticancer drugs by the action of ATP-binding cassette transporters as well as plasticity with regard to the transition between dormant CSC and transit-amplifying progenitor cell phenotypes. In addition, CSCs manifest the phenomenon of metabolic reprogramming, which is essential for maintenance of their self-renewal potential and their ability to adapt to changes in the tumor microenvironment. Elucidation of the molecular underpinnings of these biological features of CSCs is key to the development of novel anticancer therapies. In this review, we highlight the pathological relevance of CSCs in terms of their hallmarks and identification, the properties of their niche-both in primary tumors and at potential sites of metastasis-and their resistance to oxidative stress dependent on system xc (-).

3.
Semin Cancer Biol ; 77: 182-193, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33812986

RESUMEN

The concept of a "cancer stem cell" has evolved over the past decades, and research on cancer stem cell biology has entered into a stage of remarkable progress. Cancer stem cells are a major determining factor contributing to the establishment of phenotypic and functional intratumoral heterogeneity in synchronization with their surrounding "cancer stem cell niches." They serve as the driving force for cancer initiation, metastasis, and therapeutic resistance in various types of malignancies. In verity, reciprocal interplay between ovarian cancer stem cells and their niches involves a complex but ingeniously orchestrated tumor microenvironment within the intraperitoneal milieu and especially contribute to chemotherapy resistance in patients with advanced ovarian cancer. Herein, we review the principles of our current understanding of the biological features of ovarian cancer stem cells, focusing mainly on the precise mechanisms underlying acquired chemotherapy resistance. Furthermore, we highlight the specific roles of various cancer-associated stromal and immune cells in creating possible cancer stem cell niches that regulate ovarian cancer stemness.


Asunto(s)
Carcinoma Epitelial de Ovario/patología , Resistencia a Antineoplásicos/fisiología , Células Madre Neoplásicas/patología , Nicho de Células Madre/fisiología , Microambiente Tumoral/fisiología , Animales , Femenino , Humanos
4.
Metabolites ; 11(1)2021 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-33401672

RESUMEN

There is a growing body of evidence that metabolic reprogramming contributes to the acquisition and maintenance of robustness associated with malignancy. The fine regulation of expression levels of amino acid and monocarboxylate transporters enables cancer cells to exhibit the metabolic reprogramming that is responsible for therapeutic resistance. Amino acid transporters characterized by xCT (SLC7A11), ASCT2 (SLC1A5), and LAT1 (SLC7A5) function in the uptake and export of amino acids such as cystine and glutamine, thereby regulating glutathione synthesis, autophagy, and glutaminolysis. CD44 variant, a cancer stem-like cell marker, stabilizes the xCT antiporter at the cellular membrane, and tumor cells positive for xCT and/or ASCT2 are susceptible to sulfasalazine, a system Xc(-) inhibitor. Inhibiting the interaction between LAT1 and CD98 heavy chain prevents activation of the mammalian target of rapamycin (mTOR) complex 1 by glutamine and leucine. mTOR signaling regulated by LAT1 is a sensor of dynamic alterations in the nutrient tumor microenvironment. LAT1 is overexpressed in various malignancies and positively correlated with poor clinical outcome. Metabolic reprogramming of glutamine occurs often in cancer cells and manifests as ASCT2-mediated glutamine addiction. Monocarboxylate transporters (MCTs) mediate metabolic symbiosis, by which lactate in cancer cells under hypoxia is exported through MCT4 and imported by MCT1 in less hypoxic regions, where it is used as an oxidative metabolite. Differential expression patterns of transporters cause functional intratumoral heterogeneity leading to the therapeutic resistance. Therefore, metabolic reprogramming based on these transporters may be a promising therapeutic target. This review highlights the pathological function and therapeutic targets of transporters including xCT, ASCT2, LAT1, and MCT.

7.
Exp Dermatol ; 29(11): 1069-1079, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32875660

RESUMEN

In 2018, Schneider and Zouboulis analysed the available tools for studying sebaceous gland pathophysiology in vitro. Since then, the interest in this field remains unbroken, as demonstrated by recent reviews on sebaceous gland physiology, endocrinology and neurobiology, the role of sebaceous glands beyond acne, and several original works on different areas of sebaceous gland function, including sebaceous lipogenesis. Landmark developments in the first part of the 30-year modelling research dedicated to the sebaceous gland, which is considered by several scientists as the brain of the skin, were the short-term culture of human sebaceous glands, the culture of human sebaceous gland cells and the development of immortalized sebaceous gland cell lines exhibiting characteristics of normal sebocytes. On the other hand, current developments represent the establishment of sebaceous gland spheroids, the 3D-SeboSkin model of viable skin explants ex vivo, the combination of culture-expanded epidermal stem cells of mice and adult humans to form de novo hair follicles and sebaceous glands, when they are transplanted into excisional wounds in mice, and 3D-printed scaffolds coated with decellularized matrix of adipose-derived mesenchymal stromal cells and SZ95 sebocytes. These novel tools may become useful platforms for better understanding of cellular and molecular mechanisms governing sebocyte biology and sebaceous gland homeostasis, such as the changes in sebum synthesis and composition, the infundibular differentiation and the influence of the innate immunity and the cutaneous microbiome and for identifying potential therapeutic targets of skin diseases affecting the sebaceous glands.


Asunto(s)
Línea Celular , Modelos Biológicos , Glándulas Sebáceas/citología , Glándulas Sebáceas/fisiopatología , Enfermedades de la Piel/patología , Enfermedades de la Piel/fisiopatología , Diferenciación Celular , Humanos , Sebo/metabolismo , Piel Artificial , Células Madre/fisiología , Técnicas de Cultivo de Tejidos
8.
Front Oncol ; 10: 791, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32547946

RESUMEN

Cancer cells generate large amounts of lactate derived from glucose regardless of the available oxygen level. Cancer cells finely control ATP synthesis by modulating the uptake of substrates and the activity of enzymes involved in aerobic glycolysis (Warburg effect), which enables them to adapt to the tumor microenvironment. However, increasing evidence suggests that mitochondrial metabolism, including the tricarboxylic acid (TCA) cycle, oxidative phosphorylation (OXPHOS), and glutaminolysis, is paradoxically activated in MYCN-amplified malignancies. Unlike non-amplified cells, MYCN-amplified cancer cells significantly promote OXPHOS-dependent ATP synthesis. Furthermore, tumor cells are differentially dependent on fatty acid ß-oxidation (FAO) according to N-Myc status. Therefore, upregulation of FAO-associated enzymes is positively correlated with both N-Myc expression level and poor clinical outcome. This review explores therapeutic strategies targeting cancer stem-like cells for the treatment of tumors associated with MYCN amplification.

9.
J Exp Clin Cancer Res ; 39(1): 112, 2020 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-32546182

RESUMEN

Accumulating evidence indicates that intratumoral heterogeneity contributes to the development of resistance to anticancer therapeutics. Fibroblasts, which are components of the paraneoplastic stroma, play a crucial role in the wound-healing process. Activated fibroblasts accumulate in the wound and are involved in many aspects of the tissue remodeling cascade that initiates the repair process and prevents further tissue damage. The pathophysiological roles of cancer-associated fibroblasts (CAFs) in the heterogeneous tumor microenvironment have attracted increasing interest. CAFs play crucial roles in tumor progression and the response to chemotherapy. Several cytokines and chemokines are involved in the conversion of normal fibroblasts into CAFs, and some of these form a feedback loop between cancer cells and CAFs. In addition, the physical force between tumor cells and CAFs promotes cooperative invasion or co-migration of both types of cells. Pro-inflammatory cytokines, such as leukemia inhibitory factor (LIF) and interleukin-6 (IL-6), are secreted by both cancer cells and CAFs, and mediate the epigenetic modification of CAFs. This enhances the pro-tumorigenic function of CAFs mediated by promoting actomyosin contractility and extracellular matrix remodeling to form the tracks used for collective cancer cell migration. The concept of intra-tumoral CAF heterogeneity refers to the presence of inflammatory CAFs with low levels of α-smooth muscle actin (α-SMA) and high levels of IL-6 expression, which are in striking contrast to transforming growth factor-ß (TGF-ß)-dependent myofibroblastic CAFs with high α-SMA expression levels. CAF populations that suppress tumor growth and progression through stroma-specific Hedgehog (Hh) activation have been detected in different murine tumor models including those of the bladder, colon, and pancreas. A new therapeutic strategy targeting CAFs is the "stromal switch," in which tumor-promoting CAFs are changed into tumor-retarding CAFs with attenuated stromal stiffness. Several molecular mechanisms that can be exploited to design personalized anticancer therapies targeting CAFs remain to be elucidated. Strategies aimed at targeting the tumor stroma as well as tumor cells themselves have attracted academic attention for their application in precision medicine. This novel review discusses the role of the activation of EGFR, Wnt/ß-catenin, Hippo, TGF-ß, and JAK/STAT cascades in CAFs in relation to the chemoresistance and invasive/metastatic behavior of cancer cells. For instance, although activated EGFR signaling contributes to collective cell migration in cooperation with CAFs, an activated Hippo pathway is responsible for stromal stiffness resulting in the collapse of neoplastic blood vessels. Therefore, identifying the signaling pathways that are activated under specific conditions is crucial for precision medicine.


Asunto(s)
Fibroblastos Asociados al Cáncer/patología , Neoplasias/clasificación , Neoplasias/patología , Animales , Humanos , Patología Molecular , Transducción de Señal
13.
Orthopade ; 49(3): 277-286, 2020 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-32095865

RESUMEN

Due to the increasing number of endoprosthetic joint replacement operations in older patients as well as in patients with severe primary diseases and comorbidities, the number of revision operations is continuously increasing due to infections. The infection of an endoprosthesis represents a complex clinical picture. This article provides a detailed overview of the treatment of periprosthetic infections with a focus on the diagnostic approach and treatment decision-making. A differentiation is made in periprosthetic infections between infections with a mature or immature biofilm on the surface of the implant. Depending on this, different treatment concepts are available. Highly acute infections represent an orthopedic/surgical emergency in artificial as well as in native joints. Low-grade infections play a role particularly in the area of exchange endoprosthetics. The greatest possible success is achieved only by the interplay of a timely diagnosis, sufficient surgical approach and individualized anti-infective treatment.


Asunto(s)
Artroplastia de Reemplazo , Infecciones Relacionadas con Prótesis , Anciano , Humanos , Reoperación
14.
J Hematol Oncol ; 13(1): 4, 2020 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-31910904

RESUMEN

Patient-derived tumor xenografts (PDXs), in which tumor fragments surgically dissected from cancer patients are directly transplanted into immunodeficient mice, have emerged as a useful model for translational research aimed at facilitating precision medicine. PDX susceptibility to anti-cancer drugs is closely correlated with clinical data in patients, from whom PDX models have been derived. Accumulating evidence suggests that PDX models are highly effective in predicting the efficacy of both conventional and novel anti-cancer therapeutics. This also allows "co-clinical trials," in which pre-clinical investigations in vivo and clinical trials could be performed in parallel or sequentially to assess drug efficacy in patients and PDXs. However, tumor heterogeneity present in PDX models and in the original tumor samples constitutes an obstacle for application of PDX models. Moreover, human stromal cells originally present in tumors dissected from patients are gradually replaced by host stromal cells as the xenograft grows. This replacement by murine stroma could preclude analysis of human tumor-stroma interactions, as some mouse stromal cytokines might not affect human carcinoma cells in PDX models. The present review highlights the biological and clinical significance of PDX models and three-dimensional patient-derived tumor organoid cultures of several kinds of solid tumors, such as those of the colon, pancreas, brain, breast, lung, skin, and ovary.


Asunto(s)
Neoplasias/patología , Técnicas de Cultivo de Órganos , Organoides/patología , Ensayos Antitumor por Modelo de Xenoinjerto , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Modelos Animales de Enfermedad , Humanos , Neoplasias/tratamiento farmacológico , Técnicas de Cultivo de Órganos/métodos , Organoides/efectos de los fármacos , Microambiente Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
15.
Cancers (Basel) ; 11(7)2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-31311148

RESUMEN

We hypothesized that sorafenib plus transarterial chemoembolization (TACE) would confer survival benefits over sorafenib alone for advanced hepatocellular carcinoma (aHCC). We investigated this while using the population-based All-Cancer Dataset to assemble a cohort (n = 3674; median age, 60; 83% men) of patients receiving sorafenib for aHCC (Child-Pugh A) with macro-vascular invasion or nodal/distant metastases. The patients were classified into the sorafenib-TACE group (n = 426) or the propensity score-matched sorafenib-alone group (n = 1686). All of the participants were followed up until death or the end of the study. Time-dependent Cox model and the Mantel-Byar test were used for survival analysis. During the median follow-ups of 221 and 133 days for the sorafenib-TACE and sorafenib-alone groups, 164 (39%) and 916 (54%) deaths occurred, respectively; the corresponding median overall survivals (OS) were 381 and 204 days, respectively (hazard ratio, HR: 0.74; 95% confidence interval, CI, 0.63-0.88; p = 0.021). The one-year and six-month OS were 53.5% and 80.3% in the sorafenib-TACE group and 32.4% and 54.4% in the sorafenib-alone group, respectively. The major complications were comparable between the two groups. The addition of TACE to sorafenib improves survival, with a 26% reduction in mortality. These findings provide strong real-world evidence that supports this combination strategy for eligible Child-Pugh A aHCC patients.

16.
Int J Mol Sci ; 20(9)2019 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-31067787

RESUMEN

: Neoplastic epithelial cells coexist in carcinomas with various non-neoplastic stromal cells, together creating the tumor microenvironment. There is a growing interest in the cross-talk between tumor cells and stromal fibroblasts referred to as carcinoma-associated fibroblasts (CAFs), which are frequently present in human carcinomas. CAF populations extracted from different human carcinomas have been shown to possess the ability to influence the hallmarks of cancer. Indeed, several mechanisms underlying CAF-promoted tumorigenesis are elucidated. Activated fibroblasts in CAFs are characterized as alpha-smooth muscle actin-positive myofibroblasts and actin-negative fibroblasts, both of which are competent to support tumor growth and progression. There are, however, heterogeneous CAF populations presumably due to the diverse sources of their progenitors in the tumor-associated stroma. Thus, molecular markers allowing identification of bona fide CAF populations with tumor-promoting traits remain under investigation. CAFs and myofibroblasts in wound healing and fibrosis share biological properties and support epithelial cell growth, not only by remodeling the extracellular matrix, but also by producing numerous growth factors and inflammatory cytokines. Notably, accumulating evidence strongly suggests that anti-fibrosis agents suppress tumor development and progression. In this review, we highlight important tumor-promoting roles of CAFs based on their analogies with wound-derived myofibroblasts and discuss the potential therapeutic strategy targeting CAFs.


Asunto(s)
Carcinogénesis/metabolismo , Carcinoma/metabolismo , Fibroblastos/metabolismo , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Carcinogénesis/patología , Carcinoma/tratamiento farmacológico , Carcinoma/patología , Fibroblastos/efectos de los fármacos , Fibroblastos/patología , Humanos , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología
19.
J Exp Clin Cancer Res ; 37(1): 285, 2018 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-30477547

RESUMEN

In the publication of this article [1] there are three errors.

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