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1.
Am J Ophthalmol ; 220: 102-109, 2020 12.
Article in English | MEDLINE | ID: mdl-32681908

ABSTRACT

PURPOSE: The main purpose of this paper was to describe the unique accumulation of cases of uveal melanoma (UM). All patients were white and did not have known occupational risk factors. From the authors' standpoint, there were no lifestyle factors in common in the reported cases. Results of more extensive analyses, including geospatial analysis, are currently being conducted and will be presented in a separate paper. DESIGN: Observational case series. METHODS: Descriptive data from medical records, patient interviews, and questionnaires were obtained from 5 patients from North Carolina, 6 patients from Alabama, and 14 patients from New York. Standard incidence ratio (SIR) calculations were provided by the respective states' cancer registries. UM is the most common primary malignant eye tumor in adults, although it is rare, with 2,500 cases diagnosed annually in the United States. Despite a growing understanding of the molecular characteristics, there remains uncertainty regarding epidemiologic trends and environmental risk factors. This study identified 3 geographic accumulations of UM: 1) Huntersville, NC; 2) Auburn, AL; and 3) Broome and Tioga Counties, New York. Investigation of these groups will guide ongoing efforts to discover potential risk factor and assist with future treatment and prevention. RESULTS: In North Carolina, 5 females who were identified as living in Huntersville, NC, were diagnosed with UM at ages 20, 22, 24, 30, and 31. The SIR calculations considering the observed and expected incidence ratios was 0.7 (95% confidence interval [CI], 0.5-0.9) in Mecklenburg County. In Alabama, 6 individuals who were identified as either attending Auburn University or employed there from 1989 to 1993 had diagnoses of UM. Initial SIR calculations for white females of all ages was 1.15 (95% CI, 0.989-1.328). In New York, SIR for Broome and Tioga counties were 0.93 and not significant. However, in Tioga county, for males and females and females alone, SIRs were 2.00 (P = .04) and 3.33 (P = .006). CONCLUSIONS: Although most of the conclusions that the SIR does not meet statistical criteria that defines these accumulations as true "cancer clusters," considering the incidence and demographics of UM, these accumulations of cases is unexpected and worth additional exploration. Further investigation into these cases with additional geospatial analyses and blood and tumor testing is ongoing. Information learned from the study of these unique populations may inform a better understanding of the pathogenesis of UM.


Subject(s)
Melanoma/epidemiology , Registries , Uveal Neoplasms/epidemiology , Alabama/epidemiology , Female , Humans , Incidence , Male , Middle Aged , New York/epidemiology , North Carolina/epidemiology , Risk Factors , Young Adult
2.
Nat Commun ; 11(1): 3479, 2020 07 13.
Article in English | MEDLINE | ID: mdl-32661250

ABSTRACT

Genetic factors contribute to the risk of thrombotic diseases. Recent genome wide association studies have identified genetic loci including SLC44A2 which may regulate thrombosis. Here we show that Slc44a2 controls platelet activation and thrombosis by regulating mitochondrial energetics. We find that Slc44a2 null mice (Slc44a2(KO)) have increased bleeding times and delayed thrombosis compared to wild-type (Slc44a2(WT)) controls. Platelets from Slc44a2(KO) mice have impaired activation in response to thrombin. We discover that Slc44a2 mediates choline transport into mitochondria, where choline metabolism leads to an increase in mitochondrial oxygen consumption and ATP production. Platelets lacking Slc44a2 contain less ATP at rest, release less ATP when activated, and have an activation defect that can be rescued by exogenous ADP. Taken together, our data suggest that mitochondria require choline for maximum function, demonstrate the importance of mitochondrial metabolism to platelet activation, and reveal a mechanism by which Slc44a2 influences thrombosis.


Subject(s)
Membrane Transport Proteins/metabolism , Mitochondria/metabolism , Platelet Activation/physiology , Thrombosis/metabolism , Adenosine Triphosphate/metabolism , Animals , Blotting, Western , Disease Models, Animal , Genome-Wide Association Study , Male , Mass Spectrometry , Membrane Transport Proteins/genetics , Mice , Mice, Knockout , Mitochondria/genetics , Platelet Activation/genetics , Platelet Aggregation/genetics , Platelet Aggregation/physiology , Real-Time Polymerase Chain Reaction , Thrombosis/genetics
4.
Cancers (Basel) ; 12(1)2020 Jan 01.
Article in English | MEDLINE | ID: mdl-31906411

ABSTRACT

There is no FDA-approved treatment for metastatic uveal melanoma (UM) and overall outcomes are generally poor for those who develop liver metastasis. We performed a retrospective single-institution chart review on consecutive series of UM patients with liver metastasis who were treated at Thomas Jefferson University Hospital between 1971-1993 (Cohort 1, n = 80), 1998-2007 (Cohort 2, n = 198), and 2008-2017 (Cohort 3, n = 452). In total, 70% of patients in Cohort 1 received only systemic therapies as their treatment modality for liver metastasis, while 98% of patients in Cohort 2 and Cohort 3 received liver-directed treatment either alone or with systemic therapy. Median Mets-to-Death OS was shortest in Cohort 1 (5.3 months, 95% CI: 4.2-7.0), longer in Cohort 2 (13.6 months, 95% CI: 12.2-16.6) and longest in Cohort 3 (17.8 months, 95% CI: 16.6-19.4). Median Eye Tx-to-Death OS was shortest in Cohort 1 (40.8 months, 95% CI: 37.1-56.9), and similar in Cohort 2 (62.6 months, 95% CI: 54.6-71.5) and Cohort 3 (59.4 months, 95% CI: 56.2-64.7). It is speculated that this could be due to the shift of treatment modalities from DTIC-based chemotherapy to liver-directed therapies. Combination of liver-directed and newly developed systemic treatments may further improve the survival of these patients.

5.
J Pharmacol Exp Ther ; 369(2): 182-187, 2019 05.
Article in English | MEDLINE | ID: mdl-30765424

ABSTRACT

Platelets are key mediators of thrombosis. Many agonists of platelet activation are known, but fewer endogenous inhibitors of platelets, such as prostacyclin and nitric oxide (NO), have been identified. Acetylcholinesterase inhibitors, such as donepezil, can cause bleeding in patients, but the underlying mechanisms are not well understood. We hypothesized that acetylcholine is an endogenous inhibitor of platelets. We measured the effect of acetylcholine or analogs of acetylcholine on human platelet activation ex vivo. Acetylcholine and analogs of acetylcholine inhibited platelet activation, as measured by P-selectin translocation and glycoprotein IIb IIIa conformational changes. Conversely, we found that antagonists of the acetylcholine receptor, such as pancuronium, enhance platelet activation. Furthermore, drugs inhibiting acetylcholinesterase, such as donepezil, also inhibit platelet activation, suggesting that platelets release acetylcholine. We found that NO mediates acetylcholine inhibition of platelets. Our data suggest that acetylcholine is an endogenous inhibitor of platelet activation. The cholinergic system may be a novel target for antithrombotic therapies.


Subject(s)
Acetylcholine/pharmacology , Platelet Activation/drug effects , Acetylcholine/metabolism , Blood Platelets/drug effects , Blood Platelets/physiology , Humans , Nitric Oxide/metabolism , Receptors, Cholinergic/metabolism
6.
Circulation ; 139(5): 620-635, 2019 01 29.
Article in English | MEDLINE | ID: mdl-30586737

ABSTRACT

BACKGROUND: Factor VIII (FVIII) and its carrier protein von Willebrand factor (VWF) are associated with risk of arterial and venous thrombosis and with hemorrhagic disorders. We aimed to identify and functionally test novel genetic associations regulating plasma FVIII and VWF. METHODS: We meta-analyzed genome-wide association results from 46 354 individuals of European, African, East Asian, and Hispanic ancestry. All studies performed linear regression analysis using an additive genetic model and associated ≈35 million imputed variants with natural log-transformed phenotype levels. In vitro gene silencing in cultured endothelial cells was performed for candidate genes to provide additional evidence on association and function. Two-sample Mendelian randomization analyses were applied to test the causal role of FVIII and VWF plasma levels on the risk of arterial and venous thrombotic events. RESULTS: We identified 13 novel genome-wide significant ( P≤2.5×10-8) associations, 7 with FVIII levels ( FCHO2/TMEM171/TNPO1, HLA, SOX17/RP1, LINC00583/NFIB, RAB5C-KAT2A, RPL3/TAB1/SYNGR1, and ARSA) and 11 with VWF levels ( PDHB/PXK/KCTD6, SLC39A8, FCHO2/TMEM171/TNPO1, HLA, GIMAP7/GIMAP4, OR13C5/NIPSNAP, DAB2IP, C2CD4B, RAB5C-KAT2A, TAB1/SYNGR1, and ARSA), beyond 10 previously reported associations with these phenotypes. Functional validation provided further evidence of association for all loci on VWF except ARSA and DAB2IP. Mendelian randomization suggested causal effects of plasma FVIII activity levels on venous thrombosis and coronary artery disease risk and plasma VWF levels on ischemic stroke risk. CONCLUSIONS: The meta-analysis identified 13 novel genetic loci regulating FVIII and VWF plasma levels, 10 of which we validated functionally. We provide some evidence for a causal role of these proteins in thrombotic events.


Subject(s)
Arterial Occlusive Diseases/genetics , Blood Coagulation Disorders, Inherited/genetics , Blood Coagulation/genetics , Factor VIII/analysis , Genetic Loci , Venous Thrombosis/genetics , von Willebrand Factor/analysis , Arterial Occlusive Diseases/blood , Arterial Occlusive Diseases/ethnology , Biomarkers/blood , Blood Coagulation Disorders, Inherited/blood , Blood Coagulation Disorders, Inherited/ethnology , Genetic Markers , Genetic Predisposition to Disease , Genome-Wide Association Study , Humans , Mendelian Randomization Analysis , Phenotype , Ribosomal Protein L3 , Risk Factors , Venous Thrombosis/blood , Venous Thrombosis/ethnology
7.
Ophthalmology ; 125(2): 210-217, 2018 02.
Article in English | MEDLINE | ID: mdl-28935400

ABSTRACT

PURPOSE: To compare overall survival in high-risk patients with primary uveal melanoma who received adjuvant sunitinib with institutional controls. DESIGN: Retrospective cohort. PARTICIPANTS: Selection criteria were (1) monosomy 3 and 8q amplification by cytogenetic or DecisionDx-UM Class 2 and (2) monosomy 3 and large tumor size (T3-4 by American Joint Committee on Cancer classification). Exclusion criteria were date of diagnosis before 2007 or after 2013 and age <18 years. METHODS: A cohort of patients who intended to receive adjuvant sunitinib for 6 months was compared with institutional historical controls with the same risk factors. Kaplan-Meier and Cox proportional hazards models were used to analyze the outcome. Propensity score was used to adjust for nonrandom assignment to sunitinib. MAIN OUTCOME MEASURES: Overall survival. RESULTS: From the Wills Eye Hospital Oncology Service Uveal Melanoma Cytogenetic Database (N = 1172), 128 patients fulfilled the selection and exclusion criteria. Median follow-up was 52.7 months (range, 0.26-108 months). A total of 54 patients received sunitinib. Their median age was 56 years (range, 29-81 years), and 48% were men. A total of 74 historical controls in the same risk category were identified. Their median age was 62 years (21-80 years), and 48% were men. Patients in the sunitinib group had worse cytogenetic or molecular features (monosomy 3 and 8q amplification or class 2 87% vs. 57%; P < 0.001), had smaller tumor sizes (T3-4 56% vs. 83%; P = 0.001), and were younger. There were 51 deaths, 14 (26%) in the sunitinib group and 37 (50%) in the control group. In the univariate analysis, the sunitinib group had longer overall survival (hazard ratio, 0.53; 95% confidence interval, 0.29-0.99; P = 0.041). In multivariate Cox regression analysis, interaction between use of sunitinib and age as a dichotomous variable was highly significant (P = 0.003). The following variables were statistically associated with prediction of overall survival: cytogenetic/molecular status (P = 0.015), T-size category (P = 0.022), gender (P = 0.040), and adjuvant sunitinib in patients aged <60 years (P = 0.004). Results were confirmed by propensity score analysis. CONCLUSIONS: In this retrospective study, the use of sunitinib in the adjuvant setting was associated with better overall survival.


Subject(s)
Indoles/administration & dosage , Melanoma/therapy , Pyrroles/administration & dosage , Risk Assessment , Uveal Neoplasms/therapy , Adult , Aged , Aged, 80 and over , Antineoplastic Agents/administration & dosage , Chemotherapy, Adjuvant , Female , Follow-Up Studies , Humans , Incidence , Male , Melanoma/diagnosis , Melanoma/epidemiology , Middle Aged , Proportional Hazards Models , Retrospective Studies , Sunitinib , Survival Rate/trends , Treatment Outcome , United States/epidemiology , Uveal Neoplasms/diagnosis , Uveal Neoplasms/epidemiology , Young Adult
8.
Immunotherapy ; 9(16): 1323-1330, 2017 12.
Article in English | MEDLINE | ID: mdl-29185395

ABSTRACT

AIM: To compare PD-L1 expression between metastatic uveal melanoma (MUM) and metastatic cutaneous melanoma (MCM). MATERIALS & METHODS: A total of 295 MCM and 78 MUM specimens were analyzed for tumor cell PD-L1 expression. Additionally, 91 MCM and 45 MUM specimens were analyzed for PD-1 expression on tumor-infiltrating lymphocytes. RESULTS: A total of 77/295 (26.1%) MCM specimens expressed PD-L1 as compared to 4/78 (5.1%) MUM specimens (p < 0.0001). PD-1 expression on tumor-infiltrating lymphocytes was greater in MCM (73.6%; 67/91) than in MUM (51.1%; 23/45), respectively (p = 0.009). CONCLUSION: Significant differences exist in PD-L1 expression between MCM and MUM. The lower PD-L1 expression in MUM may provide a rationale for failure of PD-1 inhibitor therapy and suggests that immune evasion in this disease may occur via alternative mechanisms.


Subject(s)
Antibodies, Monoclonal/therapeutic use , B7-H1 Antigen/immunology , Immunotherapy/methods , Lymphocytes, Tumor-Infiltrating/physiology , Melanoma/metabolism , Skin Neoplasms/metabolism , Uveal Neoplasms/metabolism , Diagnosis, Differential , Gene Expression Regulation , Humans , Melanoma/diagnosis , Melanoma/therapy , Neoplasm Metastasis , Prognosis , Skin Neoplasms/diagnosis , Skin Neoplasms/therapy , Treatment Outcome , Tumor Escape , Uveal Neoplasms/diagnosis , Uveal Neoplasms/therapy
9.
JCI Insight ; 2(19)2017 10 05.
Article in English | MEDLINE | ID: mdl-28978810

ABSTRACT

Mycobacterium tuberculosis (Mtb) is a global health threat, compounded by the emergence of drug-resistant strains. A hallmark of pulmonary tuberculosis (TB) is the formation of hypoxic necrotic granulomas, which upon disintegration, release infectious Mtb. Furthermore, hypoxic necrotic granulomas are associated with increased disease severity and provide a niche for drug-resistant Mtb. However, the host immune responses that promote the development of hypoxic TB granulomas are not well described. Using a necrotic Mtb mouse model, we show that loss of Mtb virulence factors, such as phenolic glycolipids, decreases the production of the proinflammatory cytokine IL-17 (also referred to as IL-17A). IL-17 production negatively regulates the development of hypoxic TB granulomas by limiting the expression of the transcription factor hypoxia-inducible factor 1α (HIF1α). In human TB patients, HIF1α mRNA expression is increased. Through genotyping and association analyses in human samples, we identified a link between the single nucleotide polymorphism rs2275913 in the IL-17 promoter (-197G/G), which is associated with decreased IL-17 production upon stimulation with Mtb cell wall. Together, our data highlight a potentially novel role for IL-17 in limiting the development of hypoxic necrotic granulomas and reducing disease severity in TB.


Subject(s)
Granuloma/immunology , Hypoxia-Inducible Factor 1, alpha Subunit/immunology , Interleukin-17/immunology , Tuberculosis, Pulmonary/immunology , Adult , Aged , Animals , Cell Hypoxia/immunology , Female , Gene Expression Regulation/immunology , Granuloma/microbiology , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/biosynthesis , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Inflammation Mediators/metabolism , Interleukin-17/biosynthesis , Male , Mice, Inbred Strains , Middle Aged , RNA, Messenger/genetics , Tuberculosis, Pulmonary/complications , Young Adult
10.
Int J Radiat Oncol Biol Phys ; 99(1): 22-30, 2017 09 01.
Article in English | MEDLINE | ID: mdl-28816150

ABSTRACT

PURPOSE: We performed a phase 1 study to determine the maximum tolerable dose and safety of ipilimumab with stereotactic radiosurgery (SRS) or whole brain radiation therapy (WBRT) in patients with brain metastases from melanoma. METHODS AND MATERIALS: Based on the intracranial disease burden, patients underwent WBRT (arm A) or SRS (arm B). The ipilimumab starting dose was 3 mg/kg every 3 weeks, starting on day 3 of WBRT or 2 days after SRS. The ipilimumab dose was escalated to 10 mg/kg using a 2-stage, 3+3 design. The primary endpoint was to determine the maximum tolerable dose of ipilimumab combined with radiation therapy. The secondary endpoints were overall survival, intracranial and extracranial control, progression-free survival, and toxicity. The ClinicalTrials.gov registration number is NCT01703507. RESULTS: The characteristics of the 16 patients enrolled between 2011 and 2014 were mean age, 60 years; median number of brain metastases, 2 (range 1->10); and number with EC disease, 13 (81%). Treatment included WBRT (n=5), SRS (n=11), and ipilimumab 3 mg/kg (n=7) or 10 mg/kg (n=9). The median follow-up was 8 months (arm A) and 10.5 months (arm B). A total of 21 grade 1 to 2 neurotoxic effects occurred, with no dose-limiting toxicities. One patient experienced grade 3 neurotoxicity before ipilimumab administration. Ten additional grade 3 toxicities were reported, with gastrointestinal toxicities (n=5; 31%) the most common. No patient developed grade 4 or 5 toxicity. The median progression-free survival and overall survival in arm A was 2.5 months and 8 months and in arm B was 2.1 months and not reached, respectively. CONCLUSIONS: Concurrent ipilimumab 10 mg/kg with SRS is safe. The WBRT arm was closed early because of slow accrual but demonstrated safety with ipilimumab 3 mg/kg. No patient experienced dose-limiting toxicity. Larger studies, including those with combination checkpoint inhibitor therapy and SRS, are warranted.


Subject(s)
Antibodies, Monoclonal/administration & dosage , Brain Neoplasms/radiotherapy , Cranial Irradiation/methods , Melanoma/radiotherapy , Radiosurgery , Antibodies, Monoclonal/adverse effects , Brain Neoplasms/mortality , Brain Neoplasms/secondary , Cranial Irradiation/adverse effects , Cranial Irradiation/statistics & numerical data , Disease-Free Survival , Dose Fractionation, Radiation , Drug Administration Schedule , Female , Follow-Up Studies , Humans , Infusions, Intravenous , Ipilimumab , Male , Maximum Tolerated Dose , Melanoma/mortality , Melanoma/secondary , Middle Aged , Prospective Studies , Radiosurgery/adverse effects , Radiosurgery/statistics & numerical data , Time Factors
11.
J Transl Med ; 15(1): 145, 2017 06 23.
Article in English | MEDLINE | ID: mdl-28645290

ABSTRACT

BACKGROUND: Metastatic uveal melanoma is a highly fatal disease; most patients die from their hepatic metastasis within 1 year. A major drawback in the development of new treatments for metastatic uveal melanoma is the difficulty in obtaining appropriate cell lines and the lack of appropriate animal models. Patient-derived xenograft (PDX) tumor models, bearing ectopically implanted tumors at a subcutaneous site, have been developed. However, these ectopically implanted PDX models have obstacles to translational research, including a low engraftment rate, slow tumor growth, and biological changes after multiple passages due to the different microenvironment. To overcome these limitations, we developed a new method to directly transplant biopsy specimens to the liver of immunocompromised mice. RESULTS: By using two metastatic uveal melanoma cell lines, we demonstrated that the liver provides a more suitable microenvironment for tumor growth compared to subcutaneous sites and that surgical orthotopic implantation (SOI) of tumor pieces allows the creation of a liver tumor in immunocompromised mice. Subsequently, 10 of 12 hepatic metastasis specimens from patients were successfully xenografted into the immunocompromised mice (83.3% success rate) using SOI, including 8 of 10 needle biopsy specimens (80%). Additionally, four cryopreserved PDX tumors were re-implanted to new mice and re-establishment of PDX tumors was confirmed in all four mice. The serially passaged xenograft tumors as well as the re-implanted tumors after cryopreservation were similar to the original patient tumors in histologic, genomic, and proteomic expression profiles. CT imaging was effective for detecting and monitoring PDX tumors in the liver of living mice. The expression of Ki67 in original patient tumors was a predictive factor for implanted tumor growth and the success of serial passages in PDX mice. CONCLUSIONS: Surgical orthotopic implantation of hepatic metastasis from uveal melanoma is highly successful in the establishment of orthotopic PDX models, enhancing their practical utility for research applications. By using CT scan, tumor growth can be monitored, which is beneficial to evaluate treatment effects in interventional studies.


Subject(s)
Liver Neoplasms/secondary , Melanoma/pathology , Uveal Neoplasms/pathology , Xenograft Model Antitumor Assays , Adult , Aged , Animals , Cell Line, Tumor , Cluster Analysis , Cryopreservation , DNA Copy Number Variations/genetics , Female , Humans , Liver/pathology , Liver/surgery , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/genetics , Liver Neoplasms/surgery , Male , Mice , Middle Aged , Mutation/genetics , Tumor Microenvironment
12.
J Am Coll Surg ; 224(4): 652-659, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28189663

ABSTRACT

BACKGROUND: Patients with stage II melanoma have a considerable risk for recurrence. Current guidelines are imprecise as to optimal follow-up. We hypothesized that by examining recurrence patterns, we could help to better inform guidelines. STUDY DESIGN: We queried IRB-approved melanoma databases of Thomas Jefferson University and University of North Carolina, identifying 581 patients with stage II melanoma between 1996 and 2015 with at least 1 year of follow-up. Data included location of first recurrence and how recurrence was detected (ie patient symptom, physician examination, or routine surveillance imaging). Cox regression with backward elimination was used for multivariable analysis. RESULTS: One hundred and seventy-one patients had a recurrence (29.4%), the incidence increased considerably by stage sub-group. Significant predictors of recurrence included male sex (p = 0.003), ulceration (p = 0.03), and stage (p < 0.001). On multivariable analysis, male sex and stage continued to be significant (p < 0.01). For overall survival, regression, ulceration, stage, and age were significant predictors of survival. Stage, regression, and age remained significant by multivariable analysis. Patient symptoms were the most frequent mode of detection (40%), followed by physician examination (30%) and surveillance imaging (26%)-this did not differ significantly by stage. Regional nodes were the most common site of recurrence (30%), followed by lung (27%) and in-transit (18%). CONCLUSIONS: The majority of recurrences in stage II melanoma are detected by patients and their physicians and rarely by routine imaging. As such, clinical follow-up and patient education are critical factors in detection of recurrence. With the prevalence of regional nodal recurrences, ultrasound might prove to be an important strategy in early recurrence detection.


Subject(s)
Melanoma/pathology , Neoplasm Recurrence, Local/diagnosis , Skin Neoplasms/pathology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Databases, Factual , Female , Follow-Up Studies , Humans , Male , Melanoma/mortality , Middle Aged , Neoplasm Staging , Proportional Hazards Models , Retrospective Studies , Skin Neoplasms/mortality , Skin Neoplasms/therapy , Young Adult
13.
Arterioscler Thromb Vasc Biol ; 37(2): 264-270, 2017 Feb.
Article in English | MEDLINE | ID: mdl-28062498

ABSTRACT

OBJECTIVE: To identify and characterize the effect of a SNP (single-nucleotide polymorphism) in the STXBP5 locus that is associated with altered thrombosis in humans. GWAS (genome-wide association studies) have identified numerous SNPs associated with human thrombotic phenotypes, but determining the functional significance of an individual candidate SNP can be challenging, particularly when in vivo modeling is required. Recent GWAS led to the discovery of STXBP5 as a regulator of platelet secretion in humans. Further clinical studies have identified genetic variants of STXBP5 that are linked to altered plasma von Willebrand factor levels and thrombosis in humans, but the functional significance of these variants in STXBP5 is not understood. APPROACH AND RESULTS: We used CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/CRISPR-associated 9) techniques to produce a precise mouse model carrying a human coding SNP rs1039084 (encoding human p. N436S) in the STXBP5 locus associated with decreased thrombosis. Mice carrying the orthologous human mutation (encoding p. N437S in mouse STXBP5) have lower plasma von Willebrand factor levels, decreased thrombosis, and decreased platelet secretion compared with wild-type mice. This thrombosis phenotype recapitulates the phenotype of humans carrying the minor allele of rs1039084. Decreased plasma von Willebrand factor and platelet activation may partially explain the decreased thrombotic phenotype in mutant mice. CONCLUSIONS: Using precise mammalian genome editing, we have identified a human nonsynonymous SNP rs1039084 in the STXBP5 locus as a causal variant for a decreased thrombotic phenotype. CRISPR/Cas9 genetic editing facilitates the rapid and efficient generation of animals to study the function of human genetic variation in vascular diseases.


Subject(s)
Blood Coagulation/genetics , CRISPR-Associated Proteins/genetics , CRISPR-Cas Systems , Clustered Regularly Interspaced Short Palindromic Repeats , Gene Editing/methods , Nerve Tissue Proteins/genetics , Polymorphism, Single Nucleotide , R-SNARE Proteins/genetics , Thrombosis/prevention & control , Animals , Blood Platelets/metabolism , CRISPR-Associated Proteins/metabolism , Disease Models, Animal , Down-Regulation , Exocytosis , Genome-Wide Association Study , Genotype , Humans , Mice, Transgenic , Phenotype , Platelet Activation , Thrombosis/blood , Thrombosis/genetics , von Willebrand Factor/metabolism
14.
Aging (Albany NY) ; 8(5): 1064-82, 2016 05.
Article in English | MEDLINE | ID: mdl-27249230

ABSTRACT

SIRT6 is an important member of sirtuin family that represses inflammation, aging and DNA damage, three of which are causing factors for endothelial dysfunction. SIRT6 expression is decreased in atherosclerotic lesions from ApoE(-/-) mice and human patients. However, the role of SIRT6 in regulating vascular endothelial function and atherosclerosis is not well understood. Here we show that SIRT6 protects against endothelial dysfunction and atherosclerosis. Global and endothelium-specific SIRT6 knockout mice exhibited impaired endothelium-dependent vasorelaxation. Moreover, SIRT6(+/-) haploinsufficient mice fed a high-fat diet (HFD) also displayed impaired endothelium-dependent vasorelaxation. Importantly, SIRT6(+/-); ApoE(-/-) mice after HFD feeding exhibited exacerbated atherosclerotic lesion development, concurrent with increased expression of the proinflammatory cytokine VCAM-1. Loss- and gain-of-SIRT6 function studies in cultured human endothelial cells (ECs) showed that SIRT6 attenuated monocyte adhesion to ECs. RNA-sequencing profiling revealed that SIRT6 overexpression decreased the expression of multiple atherosclerosis-related genes, including proatherogenic gene TNFSF4 (tumor necrosis factor superfamily member 4). Chromatin immunoprecipitation assays showed that SIRT6 decreased TNFSF4 gene expression by binding to and deacetylating H3K9 at TNFSF4 gene promoter. Collectively, these findings demonstrate that SIRT6 play a pivotal role in maintaining endothelial function and increased SIRT6 activity could be a new therapeutic strategy to combat atherosclerotic disease.


Subject(s)
Atherosclerosis/metabolism , Endothelium, Vascular/metabolism , Sirtuins/metabolism , Animals , Apolipoproteins E/genetics , Apolipoproteins E/metabolism , Atherosclerosis/genetics , Cell Adhesion/physiology , Cells, Cultured , Endothelial Cells/metabolism , Haploinsufficiency , Humans , Membrane Glycoproteins/genetics , Membrane Glycoproteins/metabolism , Mice , Mice, Knockout , OX40 Ligand , Sirtuins/genetics , Tumor Necrosis Factors/genetics , Tumor Necrosis Factors/metabolism , Vascular Cell Adhesion Molecule-1/genetics , Vascular Cell Adhesion Molecule-1/metabolism , Vasodilation/physiology
15.
Oncotarget ; 7(25): 37622-37635, 2016 Jun 21.
Article in English | MEDLINE | ID: mdl-27191895

ABSTRACT

TRPV4 ion channel mediates vascular mechanosensitivity and vasodilation. Here, we sought to explore whether non-mechanical activation of TRPV4 could limit vascular inflammation and atherosclerosis. We found that GSK1016790A, a potent and specific small-molecule agonist of TRPV4, induces the phosphorylation and activation of eNOS partially through the AMPK pathway. Moreover, GSK1016790A inhibited TNF-α-induced monocyte adhesion to human endothelial cells. Mice given GSK1016790A showed increased phosphorylation of eNOS and AMPK in the aorta and decreased leukocyte adhesion to TNF-α-inflamed endothelium. Importantly, oral administration of GSK1016790A reduced atherosclerotic plaque formation in ApoE deficient mice fed a Western-type diet. Together, the present study suggests that pharmacological activation of TRPV4 may serve as a potential therapeutic approach to treat atherosclerosis.


Subject(s)
Atherosclerosis/drug therapy , Monocytes/drug effects , TRPV Cation Channels/agonists , Animals , Atherosclerosis/metabolism , Atherosclerosis/pathology , Cell Adhesion/drug effects , Gene Knockdown Techniques , Human Umbilical Vein Endothelial Cells , Humans , Leucine/analogs & derivatives , Leucine/pharmacology , Male , Mice , Mice, Inbred C57BL , Monocytes/pathology , Sulfonamides/pharmacology , TRPV Cation Channels/genetics , U937 Cells
16.
Am J Pathol ; 186(1): 43-56, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26613897

ABSTRACT

Uveal melanoma (UM) is a rare type of melanoma, although it is the most common primary ocular malignant tumor in adults. Nearly one-half the patients with primary UM subsequently develop systemic metastasis, preferentially to the liver. Currently, no treatment is effective for UM hepatic metastasis, and the prognosis is universally poor. The main challenge in designing a treatment strategy for UM hepatic metastasis is the lack of suitable animal models. We developed two orthotopic mouse models for human UM hepatic metastases: direct hepatic implantation model (intrahepatic dissemination model) and splenic-implantation model (hematogenous dissemination model) and investigated the tumorgenesis in the liver. A human UM cell line, established from a hepatic metastasis and nonobese diabetic severe combined immunodeficient γ mice, were used for development of in vivo tumor models. In the direct hepatic implantation model, a localized tumor developed in the liver in all cases and intrahepatic dissemination was subsequently seen in about one-half of cases. However, in the splenic implantation model, multiple hepatic metastases were observed after splenic implantation. Hepatic tumors subsequently seeded intra-abdominal metastasis; however, lung metastases were not seen. These findings are consistent with those observed in human UM hepatic metastases. These orthotopic mouse models offer useful tools to investigate the biological behavior of human UM cells in the liver.


Subject(s)
Disease Models, Animal , Liver Neoplasms/secondary , Melanoma/secondary , Uveal Neoplasms/secondary , Animals , Cell Line, Tumor , Female , Flow Cytometry , Heterografts , Humans , Immunohistochemistry , Male , Mice , Mice, Inbred NOD , Mice, SCID , Neoplasm Transplantation/methods
17.
Cell Signal ; 28(3): 117-124, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26706435

ABSTRACT

Endothelial dysfunction, characterized by impaired activation of endothelial nitric oxide (NO) synthase (eNOS) and ensued decrease of NO production, is a common mechanism of various cardiovascular pathologies, including hypertension and atherosclerosis. Laminar blood flow-mediated specific signaling cascades modulate vascular endothelial cells (ECs) structure and functions. We have previously shown that flow-stimulated Gab1 (Grb2-associated binder-1) tyrosine phosphorylation mediates eNOS activation in ECs, which in part confers laminar flow atheroprotective action. However, the molecular mechanisms whereby flow regulates Gab1 tyrosine phosphorylation and its downstream signaling events remain unclear. Here we show that platelet endothelial cell adhesion molecule-1 (PECAM1), a key molecule in an endothelial mechanosensing complex, specifically mediates Gab1 tyrosine phosphorylation and its downstream Akt and eNOS activation in ECs upon flow rather than hepatocyte growth factor (HGF) stimulation. Small interfering RNA (siRNA) targeting PECAM1 abolished flow- but not HGF-induced Gab1 tyrosine phosphorylation and Akt, eNOS activation as well as Gab1 membrane translocation. Protein-tyrosine phosphatase SHP2, which has been shown to interact with Gab1, was involved in flow signaling and HGF signaling, as SHP2 siRNA diminished the flow- and HGF-induced Gab1 tyrosine phosphorylation, membrane localization and downstream signaling. Pharmacological inhibition of PI3K decreased flow-, but not HGF-mediated Gab1 phosphorylation and membrane localization as well as eNOS activation. Finally, we observed that flow-mediated Gab1 and eNOS phosphorylation in vivo induced by voluntary wheel running was reduced in PECAM1 knockout mice. These results demonstrate a specific role of PECAM1 in flow-mediated Gab1 tyrosine phosphorylation and eNOS signaling in ECs.


Subject(s)
Phosphoproteins/metabolism , Platelet Endothelial Cell Adhesion Molecule-1/metabolism , Signal Transduction , Adaptor Proteins, Signal Transducing , Animals , Chromones/pharmacology , Hepatocyte Growth Factor/genetics , Hepatocyte Growth Factor/metabolism , Hepatocyte Growth Factor/pharmacology , Human Umbilical Vein Endothelial Cells , Humans , Mice , Mice, Inbred C57BL , Mice, Knockout , Morpholines/pharmacology , Nitric Oxide Synthase Type III/metabolism , Phosphorylation/drug effects , Platelet Endothelial Cell Adhesion Molecule-1/chemistry , Platelet Endothelial Cell Adhesion Molecule-1/genetics , Protein Tyrosine Phosphatase, Non-Receptor Type 11/antagonists & inhibitors , Protein Tyrosine Phosphatase, Non-Receptor Type 11/genetics , Protein Tyrosine Phosphatase, Non-Receptor Type 11/metabolism , Proto-Oncogene Proteins c-akt/metabolism , RNA Interference , RNA, Small Interfering/metabolism , Recombinant Proteins/biosynthesis , Recombinant Proteins/isolation & purification , Recombinant Proteins/pharmacology , Signal Transduction/drug effects , Tyrosine/metabolism
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Surg Oncol Clin N Am ; 24(2): 299-308, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25769713

ABSTRACT

Intratumoral therapy with bacteria/bacterial products dates to at least the 1890s. Over the decades this has expanded beyond the use of microbes and microbial products to include chemicals, cancer chemotherapeutic agents, cytokines, recombinant organisms, and hybrid molecules. The appeal of this method of delivery is the ability to deliver high concentrations of the therapeutic agent directly to the tumor, often with minimal side effects. This article summarizes the use and efficacy of the various agents used in the past and present in the treatment of in-transit and satellite metastases in melanoma.


Subject(s)
Adjuvants, Immunologic/administration & dosage , Antineoplastic Agents/administration & dosage , Melanoma/drug therapy , Skin Neoplasms/drug therapy , Humans , Injections, Intralesional , Melanoma/pathology , Neoplasm Metastasis/therapy , Skin Neoplasms/pathology
20.
J Vasc Interv Radiol ; 26(4): 523-32.e2, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25678394

ABSTRACT

PURPOSE: To investigate the effects of immunoembolization with granulocyte-macrophage colony-stimulating factor (GM-CSF) in patients with uveal melanoma (UM) with liver-only metastasis. MATERIALS AND METHODS: In this double-blind phase II clinical trial, patients were randomized to undergo immunoembolization or bland embolization (BE). Lobar treatment was performed with GM-CSF or normal saline solution mixed with ethiodized oil followed by embolization with gelatin sponge emulsified with iodinated contrast medium. Fifty-two patients (immunoembolization, n = 25; BE, n = 27) were enrolled. Response was assessed after every two treatments. The primary endpoint was overall response rate (ORR) of liver metastases. Progression-free survival (PFS), overall survival (OS), and immunologic responses were secondary endpoints. RESULTS: There were five partial responses in the immunoembolization group (ORR, 21.2%; 90% confidence interval [CI], 10.3%-30.5%) and three in the BE group (ORR, 16.7%; 90% CI, 6.3%-26.9%). Stable disease was seen in 12 patients in the immunoembolization group and 19 in the BE group. OS times were 21.5 months (95% CI, 18.5-24.8 mo) with immunoembolization and 17.2 months (95% CI, 11.9-22.4 mo) with BE. The degree of proinflammatory cytokine production was more robust after immunoembolization and correlated with time to "systemic" extrahepatic progression. In the immunoembolization group, interleukin (IL)-6 levels at 1 hour (P = .001) and IL-8 levels at 18 hours after the procedure (P < .001) were significant predictors of longer systemic PFS. Moreover, a dose-response pattern was evident between posttreatment serum cytokine concentrations and systemic PFS. CONCLUSIONS: Immunoembolization induced more robust inflammatory responses, which correlated with the delayed progression of extrahepatic systemic metastases.


Subject(s)
Chemoembolization, Therapeutic/methods , Granulocyte-Macrophage Colony-Stimulating Factor/administration & dosage , Liver Neoplasms/secondary , Liver Neoplasms/therapy , Melanoma/secondary , Melanoma/therapy , Adult , Aged , Aged, 80 and over , Double-Blind Method , Ethiodized Oil/administration & dosage , Female , Hemostatics/administration & dosage , Humans , Male , Middle Aged , Treatment Outcome , Uveal Neoplasms/therapy
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