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1.
Urol Case Rep ; 53: 102701, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38495851

ABSTRACT

We report a 40-year-old male presenting with right testicular pain. Following right orchiectomy demonstrating pT1bS0N0M0 teratoma with extensive necrosis, the patient opted for surveillance. With new retroperitoneal lymphadenopathy, the patient underwent a robotic-assisted laparoscopic retroperitoneal lymph node. After final pathology demonstrated extensive necrosis, the initial orchiectomy specimen was re-reviewed which revealed 60/40 ratio of non-seminomatous teratoma to nephroblastoma. Adult presentation of testicular nephroblastoma is exceedingly rare and such reports contribute to the understanding of adult teratoid Wilms tumor pathogenesis. This case emphasizes the need for comprehensive diagnostic approaches and further research into the pathophysiology of extrarenal teratoid Wilms tumors.

2.
Nat Biotechnol ; 41(8): 1117-1129, 2023 08.
Article in English | MEDLINE | ID: mdl-36702896

ABSTRACT

Cys2His2 zinc finger (ZF) domains engineered to bind specific target sequences in the genome provide an effective strategy for programmable regulation of gene expression, with many potential therapeutic applications. However, the structurally intricate engagement of ZF domains with DNA has made their design challenging. Here we describe the screening of 49 billion protein-DNA interactions and the development of a deep-learning model, ZFDesign, that solves ZF design for any genomic target. ZFDesign is a modern machine learning method that models global and target-specific differences induced by a range of library environments and specifically takes into account compatibility of neighboring fingers using a novel hierarchical transformer architecture. We demonstrate the versatility of designed ZFs as nucleases as well as activators and repressors by seamless reprogramming of human transcription factors. These factors could be used to upregulate an allele of haploinsufficiency, downregulate a gain-of-function mutation or test the consequence of regulation of a single gene as opposed to the many genes that a transcription factor would normally influence.


Subject(s)
Deep Learning , Transcription Factors , Humans , Transcription Factors/genetics , Transcription Factors/metabolism , Zinc Fingers/genetics , Gene Expression Regulation , DNA/genetics
3.
Nat Commun ; 12(1): 349, 2021 01 13.
Article in English | MEDLINE | ID: mdl-33441553

ABSTRACT

The widely used Streptococcus pyogenes Cas9 (SpCas9) nuclease derives its DNA targeting specificity from protein-DNA contacts with protospacer adjacent motif (PAM) sequences, in addition to base-pairing interactions between its guide RNA and target DNA. Previous reports have established that the PAM specificity of SpCas9 can be altered via positive selection procedures for directed evolution or other protein engineering strategies. Here we exploit in vivo directed evolution systems that incorporate simultaneous positive and negative selection to evolve SpCas9 variants with commensurate or improved activity on NAG PAMs relative to wild type and reduced activity on NGG PAMs, particularly YGG PAMs. We also show that the PAM preferences of available evolutionary intermediates effectively determine whether similar counterselection PAMs elicit different selection stringencies, and demonstrate that negative selection can be specifically increased in a yeast selection system through the fusion of compensatory zinc fingers to SpCas9.


Subject(s)
CRISPR-Associated Protein 9/metabolism , CRISPR-Cas Systems , DNA/metabolism , Gene Editing/methods , RNA, Guide, Kinetoplastida/metabolism , Streptococcus pyogenes/metabolism , Amino Acid Sequence , CRISPR-Associated Protein 9/genetics , Cell Line, Tumor , DNA/chemistry , DNA/genetics , Directed Molecular Evolution/methods , Humans , Mutation , Nucleic Acid Conformation , Nucleotide Motifs/genetics , Protein Engineering/methods , RNA, Guide, Kinetoplastida/genetics , Streptococcus pyogenes/genetics , Substrate Specificity
4.
Nucleic Acids Res ; 48(11): 6382-6402, 2020 06 19.
Article in English | MEDLINE | ID: mdl-32383734

ABSTRACT

The Cys2His2 zinc finger is the most common DNA-binding domain expanding in metazoans since the fungi human split. A proposed catalyst for this expansion is an arms race to silence transposable elements yet it remains poorly understood how this domain is able to evolve the required specificities. Likewise, models of its DNA binding specificity remain error prone due to a lack of understanding of how adjacent fingers influence each other's binding specificity. Here, we use a synthetic approach to exhaustively investigate binding geometry, one of the dominant influences on adjacent finger function. By screening over 28 billion protein-DNA interactions in various geometric contexts we find the plasticity of the most common natural geometry enables more functional amino acid combinations across all targets. Further, residues that define this geometry are enriched in genomes where zinc fingers are prevalent and specificity transitions would be limited in alternative geometries. Finally, these results demonstrate an exhaustive synthetic screen can produce an accurate model of domain function while providing mechanistic insight that may have assisted in the domains expansion.


Subject(s)
Models, Molecular , Protein Domains/physiology , Zinc Fingers/physiology , Amino Acid Sequence , Animals , Base Sequence , DNA/chemical synthesis , DNA/genetics , DNA/metabolism , Deep Learning , Humans , Hydrogen Bonding , Protein Domains/genetics , Reproducibility of Results , Substrate Specificity/genetics , Transcription Factors/chemistry , Transcription Factors/genetics , Transcription Factors/metabolism , Zinc Fingers/genetics
5.
Endocr Relat Cancer ; 25(4): 453-469, 2018 04.
Article in English | MEDLINE | ID: mdl-29431615

ABSTRACT

Despite altered metabolism being an accepted hallmark of cancer, it is still not completely understood which signaling pathways regulate these processes. Given the central role of androgen receptor (AR) signaling in prostate cancer, we hypothesized that AR could promote prostate cancer cell growth in part through increasing glucose uptake via the expression of distinct glucose transporters. Here, we determined that AR directly increased the expression of SLC2A12, the gene that encodes the glucose transporter GLUT12. In support of these findings, gene signatures of AR activity correlated with SLC2A12 expression in multiple clinical cohorts. Functionally, GLUT12 was required for maximal androgen-mediated glucose uptake and cell growth in LNCaP and VCaP cells. Knockdown of GLUT12 also decreased the growth of C4-2, 22Rv1 and AR-negative PC-3 cells. This latter observation corresponded with a significant reduction in glucose uptake, indicating that additional signaling mechanisms could augment GLUT12 function in an AR-independent manner. Interestingly, GLUT12 trafficking to the plasma membrane was modulated by calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2)-5'-AMP-activated protein kinase (AMPK) signaling, a pathway we previously demonstrated to be a downstream effector of AR. Inhibition of CaMKK2-AMPK signaling decreased GLUT12 translocation to the plasma membrane by inhibiting the phosphorylation of TBC1D4, a known regulator of glucose transport. Further, AR increased TBC1D4 expression. Correspondingly, expression of TBC1D4 correlated with AR activity in prostate cancer patient samples. Taken together, these data demonstrate that prostate cancer cells can increase the functional levels of GLUT12 through multiple mechanisms to promote glucose uptake and subsequent cell growth.


Subject(s)
Calcium-Calmodulin-Dependent Protein Kinase Kinase/metabolism , Glucose Transport Proteins, Facilitative/metabolism , Prostate/metabolism , Prostatic Neoplasms/metabolism , Receptors, Androgen/metabolism , Signal Transduction/physiology , Androgens/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Glucose Transport Proteins, Facilitative/genetics , Humans , Male , Metribolone/pharmacology , Phosphorylation/drug effects , Prostate/drug effects , Prostate/pathology , Prostatic Neoplasms/pathology , RNA, Small Interfering , Signal Transduction/drug effects
6.
Urology ; 114: 218-223, 2018 04.
Article in English | MEDLINE | ID: mdl-29378279

ABSTRACT

OBJECTIVE: To assess the association of hypoandrogenism (HA) with urethral stricture disease in a series of patients undergoing urethroplasty at 2 institutions. HA has recently been associated with increased urethral atrophy in artificial sphincter failures and decreased androgen receptors and periurethral vascularity. HA might be an etiologic factor in urethral stricture disease. METHODS: We reviewed the charts in 202 men with anterior urethral strictures between 2011 and 2017. We excluded patients with radiation-induced stricture, previous prostatectomy, previous urethroplasty, pelvic fracture-related strictures, or those on testosterone replacement. We defined HA by a total testosterone of less than 300 ng/dL. We used as age-matched cohort from a national database (National Health and Nutrition Examination Survey), as a reference. Stricture characteristics, such as length, location, and etiology were compared in HA and eugonadal groups. RESULTS: Of 202 men with anterior urethral strictures, we excluded 45. Of the remaining 157 patients, 115 (73%) had preoperative testosterone measurements. Overall, hypoandrogenism (HA) was found in 65 of 115 (57%) men in the urethral stricture group compared with 28% of age-matched men in the national database. Mean stricture length in HA and eugonadal men was 7.2 cm and 4.8 cm, respectively (P = .02). CONCLUSION: HA may be more prevalent and associated with increased disease severity in men with anterior urethral strictures. The relationship between HA and stricture formation and its potential impact on therapeutic outcomes merit further prospective investigation.


Subject(s)
Testosterone/blood , Testosterone/deficiency , Urethral Stricture/blood , Urethral Stricture/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Case-Control Studies , Humans , Male , Middle Aged , Prevalence , Retrospective Studies , Risk Factors , Severity of Illness Index , United States/epidemiology , Urethral Stricture/pathology , Young Adult
7.
Urology ; 111: 208-213, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28864340

ABSTRACT

OBJECTIVE: To evaluate clinical and patient-reported urinary and sexual outcomes after a long-segment stricture repair using the 1-sided urethral dissection, penile invagination, and dorsal buccal mucosa graft onlay technique described by Kulkarni et al. METHODS: Patients from 4 institutions after single-stage repairs for long-segment urethral strictures (>8 cm) from January 2002 to April 2016 were reviewed. Technique described by Kulkarni et al was used in all cases. Clinical outcomes included uroflowmetry (Qmax) and post-void residuals. Patient-reported outcome measures included International Prostate Symptom Score survey, Sexual Health Inventory for Men, Male Sexual Health Questionnaire, and Global Response Assessment questionnaire to measure voiding, sexual, ejaculatory symptoms, and overall improvement, respectively. RESULTS: Seventy-three patients with a minimum of 12 months' follow-up were included. The mean age and stricture length were 56 (21-80) years and 13.6 (8-21) cm, respectively. At a mean follow-up of 44 (12-162) months, 9 of 73 (12%) strictures recurred. The mean baseline International Prostate Symptom Score of 23 (7-24) decreased to 10 (1-17) on follow-up (P <.001). Eight of 42 patients (21.4%) reported an increase, and 6 of 42 patients (14.3%) decreased in Sexual Health Inventory for Men following urethroplasty. Ejaculatory function on Male Sexual Health Questionnaire improved after urethroplasty from 8 preoperatively to 11 postoperatively (P <.004). All patients reported improvement after urethroplasty on Global Response Assessment questionnaire. Post-void dribbling and chordee occurred in 45% and 25% of patients, respectively. CONCLUSION: Durable patency in most patients is demonstrated in this study. PROMs indicate an improvement in urinary function and moderate effect on sexual function. Transient penile chordee was evident in 25% of patients.


Subject(s)
Patient Reported Outcome Measures , Urethra/surgery , Urethral Stricture/surgery , Adult , Aged , Aged, 80 and over , Humans , Male , Middle Aged , Mouth Mucosa/transplantation , Retrospective Studies , Sexual Behavior/physiology , Treatment Outcome , Urethral Stricture/pathology , Urination , Urologic Surgical Procedures, Male/methods , Young Adult
8.
Sci Rep ; 7(1): 16836, 2017 12 04.
Article in English | MEDLINE | ID: mdl-29203891

ABSTRACT

RNA-guided endonucleases (RGENs) have invigorated the field of site-specific nucleases. The success of Streptococcus pyogenes Cas9 (SpCas9) has led to the discovery of several other CRISPR-associated RGENs. As more RGENs become available, it will be necessary to refine their activity before they can be translated into the clinic. With this in mind, we sought to demonstrate how deep mutational scanning (DMS) could provide details about important functional regions in SpCas9 and speed engineering efforts. Consequently, we developed a nuclease screening platform which could distinguish active Cas9 mutants. We screened a library of 1.9 × 107 with over 8500 possible non-synonymous mutations and inferred the effects of each mutation using DMS. We demonstrate that the RuvC and HNH domains are the least tolerant regions to mutation. In contrast, the Rec2 and PI domains tolerate mutation better than other regions. The mutation information defined in this work provides a foundation for further SpCas9 engineering. Together, our results demonstrate how DMS can be a powerful tool to uncover features important to RGEN function. Application of this approach to emerging RGENs should enhance their engineering and optimization for therapeutic and other applications.


Subject(s)
CRISPR-Cas Systems/genetics , Streptococcus pyogenes/genetics , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Cell Line, Tumor , DNA, Bacterial/chemistry , DNA, Bacterial/metabolism , Gene Editing , Gene Library , Humans , Hydrolases/chemistry , Hydrolases/genetics , Mutation , Plasmids/genetics , Plasmids/metabolism
9.
Neuropharmacology ; 123: 34-45, 2017 Sep 01.
Article in English | MEDLINE | ID: mdl-28504123

ABSTRACT

Friedreich's ataxia (FA) is a progressive neurodegenerative disease caused by reduced levels of the mitochondrial protein frataxin (FXN). Recombinant human erythropoietin (rhEPO) increased FXN protein in vitro and in early clinical studies, while no published reports evaluate rhEPO in animal models of FA. STS-E412 and STS-E424 are novel small molecule agonists of the tissue-protective, but not the erythropoietic EPO receptor. We find that rhEPO, STS-E412 and STS-E424 increase FXN expression in vitro and in vivo. RhEPO, STS-E412 and STS-E424 increase FXN by up to 2-fold in primary human cortical cells and in retinoic-acid differentiated murine P19 cells. In primary human cortical cells, the increase in FXN protein was accompanied by an increase in FXN mRNA, detectable within 4 h. RhEPO and low nanomolar concentrations of STS-E412 and STS-E424 also increase FXN in normal and FA patient-derived PBMC by 20%-40% within 24 h, an effect that was comparable to that by HDAC inhibitor 4b. In vivo, STS-E412 increased Fxn mRNA and protein in wild-type C57BL6/j mice. RhEPO, STS-E412, and STS-E424 increase FXN expression in the heart of FXN-deficient KIKO mice. In contrast, FXN expression in the brains of KIKO mice increased following treatment with STS-E412 and STS-E424, but not following treatment with rhEPO. Unexpectedly, rhEPO-treated KIKO mice developed severe splenomegaly, while no splenomegaly was observed in STS-E412- or STS-E424-treated mice. RhEPO, STS-E412 and STS-E424 upregulate FXN expression in vitro at equal efficacy, however, the effects of the small molecules on FXN expression in the CNS are superior to rhEPO in vivo.


Subject(s)
Erythropoietin/pharmacology , Neuroprotective Agents/pharmacology , Pyrimidines/pharmacology , Receptors, Erythropoietin/agonists , Recombinant Proteins/pharmacology , Triazoles/pharmacology , Adult , Animals , Cells, Cultured , Cerebral Cortex/drug effects , Cerebral Cortex/metabolism , Female , Friedreich Ataxia/drug therapy , Friedreich Ataxia/metabolism , Histone Deacetylase Inhibitors/pharmacology , Humans , Iron-Binding Proteins/genetics , Iron-Binding Proteins/metabolism , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/metabolism , Male , Mice, Inbred C57BL , Mice, Transgenic , Middle Aged , Neurons/drug effects , Neurons/metabolism , Receptors, Erythropoietin/metabolism , Young Adult , Frataxin
10.
Mol Pharmacol ; 88(2): 357-67, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26018904

ABSTRACT

Erythropoietin (EPO) and its receptor are expressed in a wide variety of tissues, including the central nervous system. Local expression of both EPO and its receptor is upregulated upon injury or stress and plays a role in tissue homeostasis and cytoprotection. High-dose systemic administration or local injection of recombinant human EPO has demonstrated encouraging results in several models of tissue protection and organ injury, while poor tissue availability of the protein limits its efficacy. Here, we describe the discovery and characterization of the nonpeptidyl compound STS-E412 (2-[2-(4-chlorophenoxy)ethoxy]-5,7-dimethyl-[1,2,4]triazolo[1,5-a]pyrimidine), which selectively activates the tissue-protective EPO receptor, comprising an EPO receptor subunit (EPOR) and the common ß-chain (CD131). STS-E412 triggered EPO receptor phosphorylation in human neuronal cells. STS-E412 also increased phosphorylation of EPOR, CD131, and the EPO-associated signaling molecules JAK2 and AKT in HEK293 transfectants expressing EPOR and CD131. At low nanomolar concentrations, STS-E412 provided EPO-like cytoprotective effects in primary neuronal cells and renal proximal tubular epithelial cells. The receptor selectivity of STS-E412 was confirmed by a lack of phosphorylation of the EPOR/EPOR homodimer, lack of activity in off-target selectivity screening, and lack of functional effects in erythroleukemia cell line TF-1 and CD34(+) progenitor cells. Permeability through artificial membranes and Caco-2 cell monolayers in vitro and penetrance across the blood-brain barrier in vivo suggest potential for central nervous system availability of the compound. To our knowledge, STS-E412 is the first nonpeptidyl, selective activator of the tissue-protective EPOR/CD131 receptor. Further evaluation of the potential of STS-E412 in central nervous system diseases and organ protection is warranted.


Subject(s)
Brain/embryology , Erythropoietin/metabolism , Neurons/metabolism , Pyrimidines/pharmacology , Pyrimidines/pharmacokinetics , Receptors, Erythropoietin/agonists , Triazoles/pharmacology , Triazoles/pharmacokinetics , Animals , Biological Availability , Blood-Brain Barrier/drug effects , Brain/cytology , Caco-2 Cells , Cells, Cultured , Cytokine Receptor Common beta Subunit/metabolism , HEK293 Cells , Humans , Rats , Signal Transduction/drug effects
11.
Curr Top Med Chem ; 15(10): 955-69, 2015.
Article in English | MEDLINE | ID: mdl-25832721

ABSTRACT

Parkinson's disease (PD) is a neurodegenerative disease affecting more than a million people in the USA alone. While there are effective symptomatic treatments for PD, there is an urgent need for new therapies that slow or halt the progressive death of dopaminergic neurons. Significant progress has been made in understanding the pathophysiology of PD, which has substantially facilitated the discovery efforts to identify novel drugs. The tissue-protective erythropoietin (EPO) receptor, EPOR/CD131, has emerged as one promising target for disease-modifying therapies. Recombinant human EPO (rhEPO), several variants of EPO, EPO-mimetic peptides, cell-based therapies using cells incubated with or expressing EPO, gene therapy vectors encoding EPO, and small molecule EPO mimetic compounds all show potential as therapeutic candidates. Agonists of the EPOR/CD131 receptor demonstrate potent anti-apoptotic, antioxidant, and anti-inflammatory effects and protect neurons, including dopaminergic neurons, from diverse insults in vitro and in vivo. When delivered directly to the striatum, rhEPO protects dopaminergic neurons in animal models of PD. Early-stage clinical trials testing systemic rhEPO have provided encouraging results, while additional controlled studies are required to fully assess the potential of the treatment. Poor CNS availability of proteins and challenges related to invasive delivery limit delivery of EPO protein. Several variants of EPO and small molecule agonists of the EPO receptors are making progress in preclinical studies and may offer solutions to these challenges. While EPO was initially discovered as the primary modulator of erythropoiesis, the discovery and characterization of the tissue-protective EPOR/CD131 receptor offer an opportunity to selectively target the neuroprotective receptor as an approach to identify disease-modifying treatments for PD.


Subject(s)
Antiparkinson Agents/therapeutic use , Neuroprotective Agents/therapeutic use , Parkinson Disease/drug therapy , Receptors, Erythropoietin/agonists , Animals , Humans
12.
Prehosp Emerg Care ; 18(3): 387-92, 2014.
Article in English | MEDLINE | ID: mdl-24460036

ABSTRACT

OBJECTIVES: To examine factors related to sensitivity of emergency medical services (EMS) stroke impression. METHODS: We reviewed ambulance and hospital records of all patients transported to Long Island College Hospital between January 1, 2009 and January 1, 2011 by the hospital-based EMS with a discharge diagnosis of stroke or a confounding diagnosis, and compared EMS impression to hospital discharge diagnosis. We examined relationships between EMS diagnostic sensitivity and age, gender, ethnicity, NIH Stroke Scale (NIHSS), motor signs, aphasia, neglect, lesion side, circulation, stroke type, EMS provider level, and documented Cincinnati Pre-hospital Stroke Scale (CPSS) with contingency analysis and logistic regression. RESULTS: Stroke was validated in 18% (56/310) of patients and 50% (28/56) of these were missed by EMS. EMS diagnostic sensitivity was 50% (95% CI: 36-64%), and was related to NIHSS quartile (p = 0.014), with higher sensitivities in 2nd (69%; 95% CI: 44-86%) and 3rd (75%; 95% CI: 47-91%) vs. 1st (20%; 95% CI: 7-45%) and 4th (45%; 95% CI: 21-72%) quartiles, motor signs (62 vs. 14%, p = 0.002), and documented CPSS (84 vs. 32%, p = 0.0002). EMS impression was independently related to NIHSS quartile (1st vs. 2nd adjusted OR = 9.61, 1.13-122.03, p = 0.038) and CPSS (adjusted OR = 12.58, 2.22-111.06, p = 0.003). CONCLUSION: Stroke was missed more frequently when CPSS was not documented, in patients without motor signs, and in patients with moderate-severe stroke. The sensitivity of prehospital screening for patients with moderate-severe stroke might be improved by including additional non-motor signs and by stressing indications for when screens should be performed.


Subject(s)
Diagnostic Errors/statistics & numerical data , Emergency Medical Services/methods , Stroke/diagnosis , Stroke/drug therapy , Thrombolytic Therapy/methods , Adult , Aged , Chi-Square Distribution , Cohort Studies , Databases, Factual , Emergency Medical Services/trends , Emergency Service, Hospital/statistics & numerical data , Female , Humans , Incidence , Logistic Models , Male , Middle Aged , Multivariate Analysis , Neurologic Examination/methods , Reproducibility of Results , Retrospective Studies , Risk Assessment , Sensitivity and Specificity , Severity of Illness Index , Stroke/epidemiology
14.
Am J Perinatol ; 26(8): 587-90, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19370511

ABSTRACT

The purpose of our study was to evaluate perinatal and neonatal outcomes in triplet gestations in relation to placental chorionicity. We hypothesized that triplets containing a monochorionic pair (dichorionic triamniotic) would have increased morbidity compared with triplets without a monochorionic pair (trichorionic triamniotic). We retrospectively analyzed all triplet sets > or =20 weeks delivering at our institutions from January 1995 through April 2007. Data were collected via perinatal and neonatal databases, chart review, and placental pathology. Individuals in dichorionic triamniotic triplet sets (N = 75), when compared with trichorionic triamniotic triplets (N = 309), were more likely to have a lower mean birth weight (P < 0.001) and lower gestational age at delivery (P < 0.001), spend more days in the neonatal intensive care unit (P = 0.045), have culture-proven sepsis (P = 0.02), and require intubation (P = 0.05). Multivariate analysis demonstrated that dichorionicity is not an independent cause of morbidity, but results in earlier delivery and lower birth weight. Dichorionic triamniotic triplets are at increased risk for earlier deliveries and lower birth weight at delivery compared with trichorionic triamniotic triplets.


Subject(s)
Chorion/anatomy & histology , Placenta/anatomy & histology , Pregnancy Outcome , Pregnancy, Multiple , Triplets , Adult , Apgar Score , Birth Weight , Female , Humans , Infant, Newborn , Infant, Newborn, Diseases/etiology , Pregnancy , Premature Birth
15.
Am J Perinatol ; 26(9): 617-9, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19370510

ABSTRACT

Hermansky-Pudlak syndrome (HPS) is a multisystem, autosomal-recessive disorder characterized by oculocutaneous albinism, platelet storage pool deficiency resulting in prolonged bleeding, and ceroid lipofuscin deposition. Affected individuals may suffer from blindness, pulmonary fibrosis, colitis, and bleeding diathesis. Although it has been reported in various ethnic groups, HPS is most common in individuals from the northwest corner of Puerto Rico, with a carrier incidence of 1 in 21.


Subject(s)
Hermanski-Pudlak Syndrome/diagnosis , Pregnancy Complications/diagnosis , Pregnancy Outcome , Pregnancy, High-Risk , Apgar Score , Female , Gestational Age , Hermanski-Pudlak Syndrome/therapy , Humans , Infant, Newborn , Labor, Induced/methods , Monitoring, Physiologic/methods , Pregnancy , Pregnancy Complications/therapy , Prenatal Care/methods , Rare Diseases , Risk Assessment , Young Adult
16.
J Clin Invest ; 117(9): 2486-95, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17786241

ABSTRACT

Maintenance of skeletal and cardiac muscle structure and function requires precise control of the synthesis, assembly, and turnover of contractile proteins of the sarcomere. Abnormalities in accumulation of sarcomere proteins are responsible for a variety of myopathies. However, the mechanisms that mediate turnover of these long-lived proteins remain poorly defined. We show that muscle RING finger 1 (MuRF1) and MuRF3 act as E3 ubiquitin ligases that cooperate with the E2 ubiquitin-conjugating enzymes UbcH5a, -b, and -c to mediate the degradation of beta/slow myosin heavy chain (beta/slow MHC) and MHCIIa via the ubiquitin proteasome system (UPS) in vivo and in vitro. Accordingly, mice deficient for MuRF1 and MuRF3 develop a skeletal muscle myopathy and hypertrophic cardiomyopathy characterized by subsarcolemmal MHC accumulation, myofiber fragmentation, and diminished muscle performance. These findings identify MuRF1 and MuRF3 as key E3 ubiquitin ligases for the UPS-dependent turnover of sarcomeric proteins and reveal a potential basis for myosin storage myopathies.


Subject(s)
DNA-Binding Proteins/deficiency , DNA-Binding Proteins/metabolism , Muscular Diseases/enzymology , Muscular Diseases/pathology , Myosins/metabolism , Protein Serine-Threonine Kinases/deficiency , Protein Serine-Threonine Kinases/metabolism , Animals , Chromosomal Proteins, Non-Histone , DNA-Binding Proteins/genetics , Heart Diseases/enzymology , Heart Diseases/genetics , Heart Diseases/pathology , Heart Diseases/physiopathology , Male , Mice , Mice, Knockout , Microscopy, Electron , Muscular Diseases/genetics , Polycomb Repressive Complex 1 , Protein Binding , Protein Serine-Threonine Kinases/genetics , Transcription Factors , Ubiquitin/metabolism
17.
Bioorg Med Chem Lett ; 17(17): 4987-90, 2007 Sep 01.
Article in English | MEDLINE | ID: mdl-17562361

ABSTRACT

We report the discovery of 5-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-7-(4-methylphenyl)-(E)-2,3,6,7-tetrahydro-1,4-thiazepine (2a) as an inducer of apoptosis using our proprietary cell- and caspase-based HTS assay. Through structure activity relationship (SAR) studies, 5-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-7-(2-methoxy-4-(methylthio)phenyl)-(E)-2,3,6,7-tetrahydro-1,4-thiazepine (5d) was identified as a potent apoptosis inducer with an EC(50) value of 0.08 microM in T47D cells, which was >15-fold more potent than screening hit 2a. Compound 5d also was found to be highly active in a growth inhibition assay with a GI(50) value of 0.05 microM in T47D cells and to function as an inhibitor of tubulin polymerization.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis , Caspases/metabolism , Chemistry, Pharmaceutical/methods , Neoplasms/drug therapy , Thiazepines/chemistry , Cell Line, Tumor , Cell Proliferation , Drug Design , Drug Screening Assays, Antitumor , Humans , Models, Chemical , Structure-Activity Relationship , Thiazepines/pharmacology , Tubulin/chemistry
18.
Proc Natl Acad Sci U S A ; 104(11): 4377-82, 2007 Mar 13.
Article in English | MEDLINE | ID: mdl-17360532

ABSTRACT

RING-finger proteins commonly function as ubiquitin ligases that mediate protein degradation by the ubiquitin-proteasome pathway. Muscle-specific RING-finger (MuRF) proteins are striated muscle-restricted components of the sarcomere that are thought to possess ubiquitin ligase activity. We show that mice lacking MuRF3 display normal cardiac function but are prone to cardiac rupture after acute myocardial infarction. Cardiac rupture is preceded by left ventricular dilation and a severe decrease in cardiac contractility accompanied by myocyte degeneration. Yeast two-hybrid assays revealed four-and-a-half LIM domain (FHL2) and gamma-filamin proteins as MuRF3 interaction partners, and biochemical analyses showed these proteins to be targets for degradation by MuRF3. Accordingly, FHL2 and gamma-filamin accumulated to abnormal levels in the hearts of mice lacking MuRF3. These findings reveal an important role of MuRF3 in maintaining cardiac integrity and function after acute myocardial infarction and suggest that turnover of FHL2 and gamma-filamin contributes to this cardioprotective function of MuRF3.


Subject(s)
Muscle Proteins/physiology , Myocardial Infarction/pathology , Animals , Contractile Proteins/metabolism , Echocardiography , Filamins , Homeodomain Proteins/metabolism , LIM-Homeodomain Proteins , Male , Mice , Mice, Knockout , Microfilament Proteins/metabolism , Models, Genetic , Muscle Proteins/genetics , Muscle Proteins/metabolism , Myocardium/metabolism , Protein Structure, Tertiary , Sarcomeres/metabolism , Transcription Factors/metabolism , Ubiquitin-Protein Ligases/metabolism , Up-Regulation
19.
Bioorg Med Chem Lett ; 16(18): 4884-8, 2006 Sep 15.
Article in English | MEDLINE | ID: mdl-16870445

ABSTRACT

Novel analogs of (-)-saframycin A are described. The analogs are shown to be potent inhibitors of the in vitro growth of several tumor cells in a broad panel and promising as leads for further optimization. The first in vivo studies in a solid tumor model (HCT-116) reveal potent antitumor activity with associated toxicity of daily administration.


Subject(s)
Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/pharmacology , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacokinetics , Cell Line, Tumor , Cell Proliferation/drug effects , Humans , Isoquinolines/chemical synthesis , Isoquinolines/chemistry , Isoquinolines/pharmacokinetics , Isoquinolines/pharmacology , Mice , Mice, Inbred BALB C , Molecular Structure , Structure-Activity Relationship , Xenograft Model Antitumor Assays
20.
Bioorg Med Chem Lett ; 16(17): 4554-8, 2006 Sep 01.
Article in English | MEDLINE | ID: mdl-16784854

ABSTRACT

As a continuation of our efforts to discover novel apoptosis inducers as anticancer agents using a cell-based caspase HTS assay, 2-phenyl-oxazole-4-carboxamide derivatives were identified. The structure-activity relationships of this class of molecules were explored. Compound 1k, with EC(50) of 270 nM and GI(50) of 229 nM in human colorectal DLD-1 cells, was selected and demonstrated the ability to cleave PARP and displayed DNA laddering, the hallmarks of apoptosis. Compound 1k showed 63% tumor growth inhibition in human colorectal DLD-1 xenograft mouse model at 50 mpk, bid.


Subject(s)
Amides/chemistry , Amides/pharmacology , Apoptosis/drug effects , Oxazoles/chemistry , Oxazoles/pharmacology , Amides/chemical synthesis , Animals , Cell Line, Tumor , Female , Humans , Mice , Molecular Structure , Oxazoles/chemical synthesis , Structure-Activity Relationship , Xenograft Model Antitumor Assays
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