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1.
Am Heart J Plus ; 38: 100354, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38510746

RESUMO

As cancer therapies increase in effectiveness and patients' life expectancies improve, balancing oncologic efficacy while reducing acute and long-term cardiovascular toxicities has become of paramount importance. To address this pressing need, the Cardiology Oncology Innovation Network (COIN) was formed to bring together domain experts with the overarching goal of collaboratively investigating, applying, and educating widely on various forms of innovation to improve the quality of life and cardiovascular healthcare of patients undergoing and surviving cancer therapies. The COIN mission pillars of innovation, collaboration, and education have been implemented with cross-collaboration among academic institutions, private and public establishments, and industry and technology companies. In this report, we summarize proceedings from the first two annual COIN summits (inaugural in 2020 and subsequent in 2021) including educational sessions on technological innovations for establishing best practices and aligning resources. Herein, we highlight emerging areas for innovation and defining unmet needs to further improve the outcome for cancer patients and survivors of all ages. Additionally, we provide actionable suggestions for advancing innovation, collaboration, and education in cardio-oncology in the digital era.

3.
BMC Vet Res ; 18(1): 388, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36329434

RESUMO

BACKGROUND: Bone marrow (BM)- and adipose tissue (AT)-derived mesenchymal stromal cells (MSCs) have shown potential as cell-based therapies for cartilage and bone injuries and are used increasingly in human and veterinary practice to facilitate the treatment of orthopedic conditions. However, human and rodent studies have documented a sharp decline in chondrogenic and osteogenic differentiation potential with increasing donor age, which may be problematic for the important demographic of older orthopedic patients. The aim of this study was to identify the effect of donor age on the chondrogenic and osteogenic differentiation performance of equine BM- and AT-MSCs in vitro. BM- and AT-MSCs and dermal fibroblasts (biological negative control) were harvested from horses in five different age groups (n = 4, N = 60); newborn (0 days), yearling (15-17 months), adult (5-8 years), middle-aged (12-18 years), and geriatric (≥ 22 years). Chondrogenic differentiation performance was assessed quantitatively by measuring pellet size, matrix proteoglycan levels, and gene expression of articular cartilage biomarkers. Osteogenic differentiation performance was assessed quantitatively by measuring alkaline phosphatase activity, calcium deposition, and gene expression of bone biomarkers. RESULTS: Chondrogenic and osteogenic differentiation performance of equine BM- and AT-MSCs declined with increasing donor age. BM-MSCs had a higher chondrogenic differentiation performance. AT-MSCs showed minimal chondrogenic differentiation performance in all age groups. For osteogenesis, alkaline phosphatase activity was also higher in BM-MSCs, but BM-MSCs calcium deposition was affected by donor age earlier than AT-MSCs. Chondrogenic and osteogenic differentiation performance of BM-MSCs exhibited a decline as early as between the newborn and yearling samples. Steady state levels of mRNA encoding growth factors, chondrogenic, and osteogenic biomarkers were lower with increasing donor age in both MSC types. CONCLUSIONS: The data showed that chondrogenic and osteogenic differentiation performance of equine BM-MSCs declined already in yearlings, and that AT-MSCs showed minimal chondrogenic potential, but were affected later by donor age with regards to osteogenesis (calcium deposition). The results highlight the importance of donor age considerations and MSC selection for cell-based treatment of orthopedic injuries and will help inform clinicians on when to implement or potentially cryopreserve cells. Moreover, the study provides molecular targets affected by donor age.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Cavalos , Humanos , Animais , Medula Óssea , Fosfatase Alcalina , Cálcio/metabolismo , Células Cultivadas , Diferenciação Celular , Células da Medula Óssea
6.
Curr Atheroscler Rep ; 24(6): 443-456, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35441347

RESUMO

PURPOSE OF REVIEW: Cardiovascular disease (CVD) and cancer are the first and second most common causes of death within the USA. It is well established that a diagnosis of cancer increases risk and predisposes the patient to CVD, and vice versa. Despite these associations, cancer is not yet incorporated into current CVD risk calculators, necessitating additional CV risk markers for improved stratification in this at-risk population. In this review, we consider the utility of breast arterial calcification (BAC), coronary artery calcification (CAC), clonal hematopoiesis of indeterminate potential (CHIP), and cancer and cancer treatment in CVD risk assessment. RECENT FINDINGS: There is evidence supporting the use of BAC, CAC, CHIP, and cancer and cancer treatment for improved CV risk stratification in patients with cancer and those who are being screened for cancer. BAC has been shown to predict CAC, coronary atherosclerotic plaque on coronary CTA, coronary artery stenosis on coronary angiography, and CVD events and accordingly enhances CVD risk stratification beyond the atherosclerotic CVD (ASCVD) risk pooled cohort equation. Additionally, CAC visualized on CT utilized for lung cancer screening, radiation planning, and cancer staging is predictive of coronary artery disease (CAD). Furthermore, CHIP can also be utilized in risk stratification, as the presence of CHIP carries a 40% increase in CV risk independent of traditional CV risk factors. Finally, cancer and many oncologic therapies confer a lifelong increased risk of CVD. We propose an emerging set of tools to be incorporated into the routine continuum of CVD risk assessment in individuals who have been treated for cancer or who are being screened for cancer development. In this review, we discuss BAC, CAC, CHIP, and cancer and cancer treatment as emerging risk markers in cardiovascular health assessment. Their effectiveness in predicting and influencing the burden of CVD will be discussed, along with suggestions on their incorporation into preventive cardio-oncology practice. Future research will focus on short- and long-term CVD outcomes in these populations.


Assuntos
Doenças Cardiovasculares , Doença da Artéria Coronariana , Neoplasias Pulmonares , Calcificação Vascular , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Angiografia Coronária , Doença da Artéria Coronariana/terapia , Detecção Precoce de Câncer , Humanos , Neoplasias Pulmonares/complicações , Medição de Risco , Fatores de Risco , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/epidemiologia
7.
Am Heart J Plus ; 202022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37800118

RESUMO

Study objective: Cancer and heart disease are leading causes of mortality, and cardio-oncology is emerging as a new field addressing the cardiovascular toxicities related to cancer and cancer therapy. Interdisciplinary research platforms that incorporate digital health to optimize cardiovascular health and wellness in cancer survivors are therefore needed as we advance in the digital era. Our goal was to develop the Connected Health Innovation Research Program (C.H.I.R.P.) to serve as a foundation for future integration and assessments of adoption and clinical efficacy of digital health tools for cardiovascular health and wellness in the general population and in oncology patients. Design/setting/participants: Partner companies were identified through the American Medical Association innovation platform, as well as LinkedIn and direct contact by our team. Company leaders met with our team to discuss features of their technology or software. Non-disclosure agreements were signed and data were discussed and obtained for descriptive or statistical analysis. Results: A suite of companies with technologies focused on wellness, biometrics tracking, audio companions, oxygen saturation, weight trends, sleep patterns, heart rate variability, electrocardiogram patterns, blood pressure patterns, real-time metabolism tracking, instructional video modules, or integration of these technologies into electronic health records was collated. We formed an interdisciplinary research team and established an academia-industry collaborative foundation for connecting patients with wellness digital health technologies. Conclusions: A suite of software and device technologies accessible to the cardiology and oncology population has been established and will facilitate retrospective, prospective, and case research studies assessing adoption and clinical efficacy of digital health tools in cardiology/oncology.

8.
Front Immunol ; 12: 734322, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956173

RESUMO

Osteoarthritis (OA) may result from impaired ability of synovial macrophages to resolve joint inflammation. Increasing macrophage counts in inflamed joints through injection with bone marrow mononuclear cells (BMNC) induces lasting resolution of synovial inflammation. To uncover mechanisms by which BMNC may affect resolution, in this study, differential transcriptional signatures of BMNC in response to normal (SF) and inflamed synovial fluid (ISF) were analyzed. We demonstrate the temporal behavior of co-expressed gene networks associated with traits from related in vivo and in vitro studies. We also identified activated and inhibited signaling pathways and upstream regulators, further determining their protein expression in the synovium of inflamed joints treated with BMNC or DPBS controls. BMNC responded to ISF with an early pro-inflammatory response characterized by a short spike in the expression of a NF-ƙB- and mitogen-related gene network. This response was associated with sustained increased expression of two gene networks comprising known drivers of resolution (IL-10, IGF-1, PPARG, isoprenoid biosynthesis). These networks were common to SF and ISF, but more highly expressed in ISF. Most highly activated pathways in ISF included the mevalonate pathway and PPAR-γ signaling, with pro-resolving functional annotations that improve mitochondrial metabolism and deactivate NF-ƙB signaling. Lower expression of mevalonate kinase and phospho-PPARγ in synovium from inflamed joints treated with BMNC, and equivalent IL-1ß staining between BMNC- and DPBS-treated joints, associates with accomplished resolution in BMNC-treated joints and emphasize the intricate balance of pro- and anti-inflammatory mechanisms required for resolution. Combined, our data suggest that BMNC-mediated resolution is characterized by constitutively expressed homeostatic mechanisms, whose expression are enhanced following inflammatory stimulus. These mechanisms translate into macrophage proliferation optimizing their capacity to counteract inflammatory damage and improving their general and mitochondrial metabolism to endure oxidative stress while driving tissue repair. Such effect is largely achieved through the synthesis of several lipids that mediate recovery of homeostasis. Our study reveals candidate mechanisms by which BMNC provide lasting improvement in patients with OA and suggests further investigation on the effects of PPAR-γ signaling enhancement for the treatment of arthritic conditions.


Assuntos
Células da Medula Óssea/imunologia , Leucócitos Mononucleares/imunologia , Osteoartrite/complicações , Osteoartrite/imunologia , Sinovite/complicações , Sinovite/imunologia , Transcriptoma/genética , Animais , Articulações do Carpo/imunologia , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Genômica/métodos , Cavalos , Lipopolissacarídeos/efeitos adversos , Macrófagos/imunologia , Masculino , Osteoartrite/genética , Líquido Sinovial/imunologia , Sinovite/induzido quimicamente , Sinovite/genética
9.
World J Stem Cells ; 13(7): 825-840, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34367479

RESUMO

Osteoarthritis (OA) is the most prevalent joint disease causing major disability and medical expenditures. Synovitis is a central feature of OA and is primarily driven by macrophages. Synovial macrophages not only drive inflammation but also its resolution, through a coordinated, simultaneous expression of pro- and anti-inflammatory mechanisms that are essential to counteract damage and recover homeostasis. Current OA therapies are largely based on anti-inflammatory principles and therefore block pro-inflammatory mechanisms such as prostaglandin E2 and Nuclear factor-kappa B signaling pathways. However, such mechanisms are also innately required for mounting a pro-resolving response, and their blockage often results in chronic low-grade inflammation. Following minor injury, macrophages shield the damaged area and drive tissue repair. If the damage is more extensive, macrophages incite inflammation recruiting more macrophages from the bone marrow to maximize tissue repair and ultimately resolve inflammation. However, sustained damage and inflammation often overwhelms pro-resolving mechanisms of synovial macrophages leading to the chronic inflammation and related tissue degeneration observed in OA. Recently, experimental and clinical studies have shown that joint injection with autologous bone marrow mononuclear cells replenishes inflamed joints with macrophage and hematopoietic progenitors, enhancing mechanisms of inflammation resolution, providing remarkable and long-lasting effects. Besides creating an ideal environment for resolution with high concentrations of interleukin-10 and anabolic growth factors, macrophage progenitors also have a direct role in tissue repair. Macrophages constitute a large part of the early granulation tissue, and further transdifferentiate from myeloid into a mesenchymal phenotype. These cells, characterized as fibrocytes, are essential for repairing osteochondral defects. Ongoing "omics" studies focused on identifying key drivers of macrophage-mediated resolution of joint inflammation and those required for efficient osteochondral repair, have the potential to uncover ways for developing engineered macrophages or off-the-shelf pro-resolving therapies that can benefit patients suffering from many types of arthropaties, not only OA.

10.
Cardiooncology ; 7(1): 2, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441188

RESUMO

BACKGROUND: As cardiovascular disease is a leading cause of death in cancer survivors, the new subspecialty of Cardio-Oncology has emerged to address prevention, monitoring, and management of cardiovascular toxicities to cancer therapies. During the coronavirus disease of 2019 (COVID-19) pandemic, we developed a Virtual-Hybrid Approach to build a de novo Cardio-Oncology Clinic. METHODS: We conceptualized a Virtual-Hybrid Approach including three arms: information seeking in locations with existing Cardio-Oncology clinics, information gathering at the location for a new clinic, and information sharing to report clinic-building outcomes. A retrospective review of outcomes included collection and synthesis of data from our first 3 months (at pandemic peak) on types of appointments, cancers, drugs, and cardiotoxicities. Data were presented using descriptive statistics. RESULTS: A de-novo Cardio-Oncology clinic was developed structured from the ground up to integrate virtual and in-person care in a hybrid and innovative model, using the three arms of the Virtual-Hybrid Approach. First, we garnered in-person and virtual preparation through hands-on experiences, training, and discussions in existing Cardio-Oncology Clinics and conferences. Next, we gleaned information through virtual inquiry and niche-building. With partners throughout the institution, a virtual referral process was established for outpatient referrals and inpatient e-consult referrals to actualize a hybrid care spectrum for our patients administered by a multidisciplinary hybrid care team of clinicians, ancillary support staff, and clinical pharmacists. Among the multi-subspecialty clinic sessions, approximately 50% were in Cardio-Oncology, 20% in Preventive Cardiology, and 30% in General Cardiology. In the hybrid model, the Heart & Vascular Center had started to re-open, allowing for 65% of our visits to be in person. In additional analyses, the most frequent cardiovascular diagnosis was cardiomyopathy (34%), the most common cancer drug leading to referral was trastuzumab (29%), and the most prevalent cancer type was breast cancer (42%). CONCLUSION: This Virtual-Hybrid Approach and retrospective review provides guidance and information regarding initiating a brand-new Cardio-Oncology Clinic during the pandemic for cancer patients/survivors. This report also furnishes virtual resources for patients, virtual tools for oncologists, cardiologists, and administrators tasked with starting new clinics during the pandemic, and innovative future directions for this digital pandemic to post-pandemic era.

11.
Front Vet Sci ; 7: 602403, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33363241

RESUMO

Background: Bone marrow (BM)- and adipose tissue (AT)-derived mesenchymal stem cells (MSCs) are used increasingly for autologous cell therapy in equine practice to treat musculoskeletal and other injuries. Current recommendations often call for 10-100 million MSCs per treatment, necessitating the expansion of primary cells in culture prior to therapeutic use. Of concern, human and rodent studies have shown a decline of both MSC recovery from sampled tissue and in vitro proliferative capacity with increasing donor age. This may be problematic for applications of autologous cell-based therapies in the important equine demographic of older patients. Objectives: To investigate the effect of donor age on the cellular proliferation of equine BM- and AT-MSCs. Study Design: In vitro study. Methods: BM- and AT-MSCs and dermal fibroblasts (biological control) were harvested from horses in five different age groups (n = 4, N = 60); newborn (0 days), yearling (15-17 months), adult (5-8 years), middle-aged (12-18 years), and geriatric (≥22 years). Proliferation of the cells was tested using an EdU incorporation assay and steady state mRNA levels measured for targeted proliferation, aging, and senescence biomarkers. Results: The cellular proliferation of equine BM- and AT-MSCs declined significantly in the geriatric cohort relative to the younger age groups. Proliferation levels in the two MSC types were equally affected by donor age. Analysis of steady state mRNA levels showed an up-regulation in tumor suppressors, apoptotic genes, and multiple growth factors in MSCs from old horses, and a down-regulation of some pro-cycling genes with a few differences between cell types. Main Limitations: Potential age-dependent differences in cell function parameters relevant to cell-therapy application were not investigated. Conclusions: The cellular proliferation of equine BM- and AT-MSCs declined at advanced donor ages. High levels of in vitro proliferation were observed in both MSC types from horses in the age groups below 18 years of age.

12.
FASEB J ; 34(3): 4430-4444, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32030831

RESUMO

Synovial inflammation is a central feature of osteoarthritis (OA), elicited when local regulatory macrophages (M2-like) become overwhelmed, activating an inflammatory response (M1-like). Bone marrow mononuclear cells (BMNC) are a source of naïve macrophages capable of reducing joint inflammation and producing molecules essential for cartilage metabolism. This study investigated the response of BMNC to normal (SF) and inflamed synovial fluid (ISF). Equine BMNC cultured in autologous SF or ISF (n = 8 horses) developed into macrophage-rich cultures with phenotypes similar to cells native to normal SF and became more confluent in ISF (~100%) than SF (~25%). BMNC cultured in SF or ISF were neither M1- nor M2-like, but exhibited aspects of both phenotypes and a regulatory immune response, characterized by increasing counts of IL-10+ macrophages, decreasing IL-1ß concentrations and progressively increasing IL-10 and IGF-1 concentrations. Changes were more marked in ISF and suggest that homeostatic mechanisms were preserved over time and were potentially favored by progressive cell proliferation. Collectively, our data suggest that intra-articular BMNC could increase synovial macrophage counts, potentiating the macrophage- and IL-10-associated mechanisms of joint homeostasis lost during the progression of OA, preserving the production of cytokines involved in tissue repair (PGE2 , IL-10) generally impaired by frequently used corticosteroids.


Assuntos
Líquido Sinovial/metabolismo , Sinovite/metabolismo , Animais , Proliferação de Células/fisiologia , Células Cultivadas , Citocinas/metabolismo , Feminino , Citometria de Fluxo , Cavalos , Fator de Crescimento Insulin-Like I/metabolismo , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Leucócitos Mononucleares/metabolismo , Macrófagos/metabolismo , Masculino , Sinovite/imunologia
13.
PLoS One ; 14(8): e0220728, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31415589

RESUMO

Gene-annotation enrichment is a common method for utilizing ontology-based annotations in gene and gene-product centric knowledgebases. Effective utilization of these annotations requires inferring semantic linkages by tracing paths through edges in the ontological graph, referred to as relations. However, some relations are semantically problematic with respect to scope, necessitating their omission or modification lest erroneous term mappings occur. To address these issues, we created the Gene Ontology Categorization Suite, or GOcats-a novel tool that organizes the Gene Ontology into subgraphs representing user-defined concepts, while ensuring that all appropriate relations are congruent with respect to scoping semantics. Here, we demonstrate the improvements in annotation enrichment by re-interpreting edges that would otherwise be omitted by traditional ancestor path-tracing methods. Specifically, we show that GOcats' unique handling of relations improves enrichment over conventional methods in the analysis of two different gene-expression datasets: a breast cancer microarray dataset and several horse cartilage development RNAseq datasets. With the breast cancer microarray dataset, we observed significant improvement (one-sided binomial test p-value = 1.86E-25) in 182 of 217 significantly enriched GO terms identified from the conventional path traversal method when GOcats' path traversal was used. We also found new significantly enriched terms using GOcats, whose biological relevancy has been experimentally demonstrated elsewhere. Likewise, on the horse RNAseq datasets, we observed a significant improvement in GO term enrichment when using GOcat's path traversal: one-sided binomial test p-values range from 1.32E-03 to 2.58E-44.


Assuntos
Ontologia Genética , Anotação de Sequência Molecular , Animais , Neoplasias da Mama/genética , Biologia Computacional , Bases de Dados Genéticas , Feminino , Cavalos/genética , Humanos , Bases de Conhecimento
14.
Vet Surg ; 48(3): 375-387, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30801754

RESUMO

OBJECTIVE: To determine the chondrogenic potential of cells derived from interzone tissue, the normal progenitor of articular cartilage during fetal development, compared to that of adult bone marrow-derived and adipose-derived mesenchymal cell isolates. The objective of this study was to compare the chondrogenic potential of fetal musculoskeletal progenitor cells to adult cell types, which are currently used therapeutically to facilitate joint cartilage repair in equine clinical practice. The hypothesis tested was that cells derived from interzone tissue have a chondrogenic potential that exceeds that of adult bone marrow-derived and adipose-derived mesenchymal cell isolates. STUDY DESIGN: In vitro study. ANIMALS: Six young adult horses (15-17 months of age) and 6 equine fetuses aged 45-46 days of gestation. METHODS: Three-dimensional pellet cultures were established under chondrogenic conditions with fresh, primary cells isolated from adult (articular cartilage, bone marrow, adipose, dermis) and fetal (interzone, skeletal anlagen cartilage, dermis) tissues. Cellular morphology, pellet architecture, and proteoglycan synthesis were assessed in the pellet cultures. Steady state levels of ACAN (aggrecan core protein), COL2A1 (collagen type II), and COL1A1 (collagen type I) messenger RNA (mRNA) were compared among these cell types as pellet cultures and monolayer cultures. RESULTS: Adult articular chondrocytes, fetal interzone cells, and fetal anlage cells generated the largest pellets under these chondrogenic culture conditions. Pellets derived from adult articular chondrocytes and fetal anlage cells had the highest scores on a neocartilage grading scale. Fetal anlage and adult articular chondrocyte pellets had low steady-state levels of COL1A mRNA but high COL2A1 expression. Anlage chondrocyte pellets also had the highest expression of ACAN. CONCLUSION: Adult articular chondrocytes, fetal interzone cells, and fetal anlage chondrocytes exhibited the highest chondrogenic potential. In this study, adult adipose-derived cells exhibited very limited chondrogenesis, and bone marrow-derived cells had limited and variable chondrogenic potential. CLINICAL SIGNIFICANCE: Additional investigation of the high chondrogenic potential of fetal interzone cells and anlage chondrocytes to advance cell-based therapies in diarthrodial joints is warranted.


Assuntos
Diferenciação Celular/efeitos da radiação , Condrócitos/fisiologia , Condrogênese/fisiologia , Feto/citologia , Feto/fisiologia , Cavalos/embriologia , Animais , Células da Medula Óssea , Cartilagem Articular , Técnicas de Cultura de Células , Cavalos/metabolismo , Humanos , Células-Tronco Mesenquimais
15.
Oncotarget ; 9(70): 33382-33395, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-30279968

RESUMO

Calpains are a family of calcium activated cysteine proteases which participate in a wide range of cellular functions including migration, invasion, autophagy, programmed cell death, and gene expression. Calpain-1 and calpain-2 isoforms are ubiquitously expressed heterodimers composed of isoform specific catalytic subunits coupled with an obligate common regulatory subunit encoded by capns1. Here, we report that conditional deletion of capns1 disrupted calpain-1 and calpain-2 expression and activity, and this was associated with delayed tumorigenesis and altered signaling in a transgenic mouse model of spontaneous HER2+ breast cancer and effectively blocked tumorigenesis in an orthotopic engraftment model. Furthermore, capns1 knockout in a tumor derived cell line correlated with enhanced sensitivity to the chemotherapeutic doxorubicin and the HER2/EGFR tyrosine kinase inhibitor lapatinib. Collectively, these results indicate pro-tumorigenic roles for calpains-1/2 in HER2+ breast cancer and provide evidence that calpain-1/2 inhibitors could have anti-tumor effects if used either alone or in combination with chemotherapeutics and targeted agents.

16.
Biochim Biophys Acta Mol Cell Res ; 1865(2): 221-230, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29104086

RESUMO

Calpain-1 and -2 are Ca2+-activated intracellular cysteine proteases that regulate a wide range of cellular functions through the cleavage of their protein substrates. Unlike degradative proteases, calpains make limited, transformative cleavages, typically in accessible sequences linking discrete subdomains, to irreversibly alter substrate functions. The biological roles of calpain and their interplay with calcium signaling are of significant biomedical interest as biomarkers and potential therapeutic targets in a growing number of diseases including Alzheimer's, cancer and fibrosis. Unfortunately, many of the colorimetric and fluorimetric assays that have been developed to study calpain activity suffer from low sensitivity and/or poor calpain specificity. To address the need for a highly sensitive and calpain-specific substrate suitable for in vitro and in vivo calpain activity analysis, we have developed a protein FRET probe. We inserted the optimized calpain cleavage sequence PLFAAR between cyan fluorescent protein (CFP) and yellow fluorescent protein (YFP) and modulated its flanking sequences for optimal calpain cleavage. We demonstrate greater sensitivity and calpain-specificity of an optimal 16-residue PLFAAR-based FRET substrate compared to a standard α-spectrin-based probe. The 16-residue PLFAAR protein FRET substrate is not significantly cleaved by trypsin, chymotrypsin, cathepsin-L or caspase-3, and is highly sensitive to both calpain-1 and -2. After transfection of the substrate gene into breast cancer cells the PLFAAR protein FRET product was cut in lysed wild-type cells but not in those with a calpain knock-out phenotype. Blockage of substrate cleavage in the lysates by endogenous and exogenous calpastatin was observed, and was overcome by adding extra calpain.


Assuntos
Calpaína/química , Transferência Ressonante de Energia de Fluorescência , Proteólise , Calpaína/genética , Calpaína/metabolismo , Linhagem Celular Tumoral , Humanos
17.
J Comput Biol ; 20(3): 167-87, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23461570

RESUMO

The advent of high throughput RNA-seq technology allows deep sampling of the transcriptome, making it possible to characterize both the diversity and the abundance of transcript isoforms. Accurate abundance estimation or transcript quantification of isoforms is critical for downstream differential analysis (e.g., healthy vs. diseased cells) but remains a challenging problem for several reasons. First, while various types of algorithms have been developed for abundance estimation, short reads often do not uniquely identify the transcript isoforms from which they were sampled. As a result, the quantification problem may not be identifiable, i.e., lacks a unique transcript solution even if the read maps uniquely to the reference genome. In this article, we develop a general linear model for transcript quantification that leverages reads spanning multiple splice junctions to ameliorate identifiability. Second, RNA-seq reads sampled from the transcriptome exhibit unknown position-specific and sequence-specific biases. We extend our method to simultaneously learn bias parameters during transcript quantification to improve accuracy. Third, transcript quantification is often provided with a candidate set of isoforms, not all of which are likely to be significantly expressed in a given tissue type or condition. By resolving the linear system with LASSO, our approach can infer an accurate set of dominantly expressed transcripts while existing methods tend to assign positive expression to every candidate isoform. Using simulated RNA-seq datasets, our method demonstrated better quantification accuracy and the inference of dominant set of transcripts than existing methods. The application of our method on real data experimentally demonstrated that transcript quantification is effective for differential analysis of transcriptomes.


Assuntos
Biologia Computacional/métodos , RNA Mensageiro/genética , Análise de Sequência de RNA/métodos , Estatística como Assunto , Algoritmos , Simulação por Computador , Humanos , Modelos Lineares , Células MCF-7 , RNA Mensageiro/metabolismo , Transcriptoma/genética
18.
J Reprod Dev ; 57(2): 203-11, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21139325

RESUMO

A factor responsible for progression to pregnancy establishment in the mare has not been definitively characterized. To identify factors possibly involved in the establishment of equine pregnancy, the endometrium was collected from day 13 (day 0=day of ovulation) cyclic and day 13, 19 and 25 pregnant animals. From initial subtractive hybridization studies, a calcium regulating factor, Stanniocalcin-1 (STC1) mRNA, was found as a candidate molecule expressed uniquely in the pregnant endometrium. Endometrial expression of STC1 mRNA was noted on day 19 and was markedly increased in the day 25 gravid endometrium. STC1 protein was found in the extracts of day 25 gravid endometrium and immunochemically localized in the uterine glands. In addition, STC1 protein was detected in uterine flushing media collected from day 25 pregnant mares. High concentrations of estradiol-17 ß (E(2)) were detected in day 25 conceptuses. E(2) levels were much higher in the gravid endometrium than in other regions, whereas progesterone levels did not differ among the samples from different endometrial regions. Expression of STC1 mRNA, however, was not significantly upregulated in cultured endometrial explants treated with various concentrations of E(2) (0.01-100 ng/ml) with or without 10 ng/ml progesterone. These results indicate that an increase in STC1 expression appears to coincide with capsule disappearance in the conceptus, and suggest that STC1 from the uterine glands likely plays a role in conceptus development during the pregnancy establishment period in the mare.


Assuntos
Endométrio/metabolismo , Glicoproteínas/metabolismo , Cavalos/metabolismo , Gravidez/metabolismo , Animais , Estradiol/metabolismo , Feminino , Gravidez/genética , Progesterona/metabolismo , RNA Mensageiro/metabolismo
19.
Nucleic Acids Res ; 38(18): e178, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20802226

RESUMO

The accurate mapping of reads that span splice junctions is a critical component of all analytic techniques that work with RNA-seq data. We introduce a second generation splice detection algorithm, MapSplice, whose focus is high sensitivity and specificity in the detection of splices as well as CPU and memory efficiency. MapSplice can be applied to both short (<75 bp) and long reads (≥ 75 bp). MapSplice is not dependent on splice site features or intron length, consequently it can detect novel canonical as well as non-canonical splices. MapSplice leverages the quality and diversity of read alignments of a given splice to increase accuracy. We demonstrate that MapSplice achieves higher sensitivity and specificity than TopHat and SpliceMap on a set of simulated RNA-seq data. Experimental studies also support the accuracy of the algorithm. Splice junctions derived from eight breast cancer RNA-seq datasets recapitulated the extensiveness of alternative splicing on a global level as well as the differences between molecular subtypes of breast cancer. These combined results indicate that MapSplice is a highly accurate algorithm for the alignment of RNA-seq reads to splice junctions. Software download URL: http://www.netlab.uky.edu/p/bioinfo/MapSplice.


Assuntos
Algoritmos , Processamento Alternativo , Sítios de Splice de RNA , Análise de Sequência de RNA , Software , Neoplasias da Mama/genética , Feminino , Perfilação da Expressão Gênica , Humanos
20.
Brief Funct Genomics ; 9(3): 238-50, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20348544

RESUMO

Human and equine cell transplant strategies for cartilage lesions usually result in scar tissue that is similar to what is produced naturally during the repair process. In this study, culture-expanded de-differentiated chondrocytes and primary bone marrow stromal cells at a pre-transplantation time-point were compared along with neonatal cartilage to repair tissue. Transcriptional profiling using a 9413-probeset equine-specific cDNA microarray and targeted real-time quantitative polymerase chain reaction validation were used to characterize relationships between these cell types and repair tissue both broadly and for individual cartilage biomarkers. The greatest divergence in expression was detected for transcripts encoding matrix proteins that typically define the differentiation status of normal articular cartilage and fibrocartilage repair tissue. Expression patterns and gene ontology analyses indicated that while the repair cells were more chondrogenic than bone marrow stromal cells and de-differentiated cultured chondrocytes, steady-state levels of transcripts encoding cartilage biomarkers were substantially lower than the amounts found in neonatal articular cartilage. By characterizing gene expression differences amongst these tissues, we present important targets to monitor when developing improvements to cartilage engineering therapies.


Assuntos
Células da Medula Óssea/metabolismo , Cartilagem Articular/metabolismo , Condrócitos/metabolismo , Transcrição Gênica , Cicatrização , Animais , Animais Recém-Nascidos , Biomarcadores/metabolismo , Cartilagem Articular/crescimento & desenvolvimento , Cartilagem Articular/fisiologia , Células Cultivadas , Perfilação da Expressão Gênica , Cavalos/genética , Cavalos/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Mesoderma/citologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Estromais/metabolismo
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