Transcriptional Regulation of the Synaptic Vesicle Protein Synaptogyrin-3 (SYNGR3) Gene: The Effects of NURR1 on Its Expression.

Synaptogyrin-3 (SYNGR3) is a synaptic vesicular membrane protein. Amongst four homologues (SYNGR1 to 4), SYNGR1 and 3 are especially abundant in the brain. SYNGR3 interacts with the dopamine transporter (DAT) to facilitate dopamine (DA) uptake and synaptic DA turnover in dopaminergic transmission. Perturbed SYNGR3 expression is observed in Parkinson's disease (PD). The regulatory elements which affect SYNGR3 expression are unknown. Nuclear-receptor-related-1 protein (NURR1) can regulate dopaminergic neuronal differentiation and maintenance via binding to NGFI-B response elements (NBRE). We explored whether NURR1 can regulate SYNGR3 expression using an in silico analysis of the 5'-flanking region of the human SYNGR3 gene, reporter gene activity and an electrophoretic mobility shift assay (EMSA) of potential cis-acting sites. In silico analysis of two genomic DNA segments (1870 bp 5'-flanking region and 1870 + 159 bp of first exon) revealed one X Core Promoter Element 1 (XCPE1), two SP1, and three potential non-canonical NBRE response elements (ncNBRE) but no CAAT or TATA box. The longer segment exhibited gene promoter activity in luciferase reporter assays. Site-directed mutagenesis of XCPE1 decreased promoter activity in human neuroblastoma SH-SY5Y (↓43.2%) and human embryonic kidney HEK293 cells (↓39.7%). EMSA demonstrated NURR1 binding to these three ncNBRE. Site-directed mutagenesis of these ncNBRE reduced promoter activity by 11-17% in SH-SY5Y (neuronal) but not in HEK293 (non-neuronal) cells. C-DIM12 (Nurr1 activator) increased SYNGR3 protein expression in SH-SY5Y cells and its promoter activity using a real-time luciferase assay. As perturbed vesicular function is a feature of major neurodegenerative diseases, inducing SYNGR3 expression by NURR1 activators may be a potential therapeutic target to attenuate synaptic dysfunction in PD.

Longitudinal trajectory of frailty in blood or marrow transplant survivors: Report from the Blood or Marrow Transplant Survivor Study.

BACKGROUND: Blood or bone marrow transplantation (BMT) survivors with frailty are at a higher risk of subsequent mortality. Longitudinal trends in the frailty state are not known and could help identify vulnerable subpopulations at risk of subsequent adverse events. METHODS: This study included a cohort of 470 autologous and allogeneic BMT recipients who had survived ≥2 years after BMT and completed a baseline questionnaire (t1) at a median of 7.3 years after BMT and a follow-up questionnaire (t2) 13.2 years after t1. The main outcome was change in frailty state between t1 and t2. Frailty phenotype was defined as exhibiting ≥3 of the following characteristics: clinically underweight, exhaustion, low energy expenditure, slow walking speed, and muscle weakness. The following categories of change in frailty state were evaluated: worsened, improved, and stable. RESULTS: Of the 470 participants, 36.4% were aged ≥60 years at t1, and 50.6% were men. The prevalence of frailty increased from 4.8% at t1 to 9.6% at t2. Worsening was observed in 18.8% of patients, and improvement was reported in 9.7%. Pre-BMT exposure to vincristine (odds ratio [OR], 2.1; 95% CI, 1.3-3.39) was associated with worsening. Female sex (OR, 1.5; 95% CI, 0.93-2.4) was associated with a trend toward worsening. Pre-BMT exposure to vincristine (OR, 2.79; 95% CI, 1.44-5.43), a history of chronic graft-versus-host disease (OR, 2.58; 95% CI, 1.2-5.5), and grade 3 and 4 chronic health conditions at t1 (OR, 2.1; 95% CI, 1.08-4.33) were associated with frailty at t2. CONCLUSIONS: In a cohort of BMT survivors who were followed longitudinally for a median of 20.6 years from BMT, the frailty status worsened for approximately20% over a 13-year timespan. BMT survivors who are at risk for worsening frailty could benefit from targeted interventions.

Morbidity burden in survivors of multiple myeloma who underwent autologous transplantation: A Bone Marrow Transplantation Survivor Study.

BACKGROUND: Autologous blood or bone marrow transplantation (aBMT) is considered the standard of care for patients with multiple myeloma (MM). Significantly improved survival necessitates an understanding of the morbidity burden borne by the growing survivor population. METHODS: The authors evaluated severe and/or life-threatening chronic health conditions (CHCs) and subsequent neoplasms (SNs) in patients with MM who were treated with aBMT using the Bone Marrow Transplant Survivor Study. A total of 630 study participants had undergone aBMT for MM at 1 of 3 BMT centers, had survived ≥2 years after aBMT, and were aged ≥18 years at the time of survey completion. Survivors of aBMT identified 289 nearest-age siblings to constitute an unaffected comparison group. Scoring of CHCs was based on version 5 of the National Cancer Institute Common Terminology Criteria for Adverse Events to determine severity (with grade 3 indicating serious and grade 4 indicating life-threatening). RESULTS: The 10-year cumulative incidence of any grade 3 to 4 CHC among survivors of aBMT was 57.6 ± 3.2%. Survivors of MM were found to be at 40% higher odds of developing grade 3 to 4 CHCs when compared with siblings (95% confidence interval [95% CI], 1.0-1.9). Among SNs, 96% were solid tumors, yielding a 10-year cumulative incidence of 13.6% ± 2.5%. Pre-aBMT exposure to cyclophosphamide (hazard ratio [HR], 3.5; 95% CI, 1.5-8.1) and immunomodulatory drugs (HR, 3.9; 95% CI, 1.5-10.1) were associated with an increased risk of solid tumors. Melanoma (10-year cumulative incidence: 3.3% ± 1.2%) and squamous cell carcinoma (10-year cumulative incidence: 5.1% ± 1.8%), were the most common SNs. Pre-aBMT exposure to cyclophosphamide (HR, 6.02; 95% CI, 1.4-26.1) and immunomodulatory drugs (HR, 7.9; 95% CI, 0.9-68.5) was associated with an increased risk of melanoma. CONCLUSIONS: The 10-year cumulative incidence of severe and/or life-threatening CHCs was found to approach 60% in long-term survivors of MM, with solid SNs constituting a large morbidity burden. The current study has provided evidence supporting the close monitoring of survivors to manage morbidity.

Pain in older survivors of hematologic malignancies after blood or marrow transplantation: A BMTSS report.

BACKGROUND: Blood or marrow transplantation (BMT) is increasingly offered to older adults with hematologic malignancies; however, their risk for severe pain is poorly understood. Using the Bone Marrow Transplant Survivor Study, the current study investigated the prevalence and predictors of pain after BMT (allogeneic or autologous) as well as its association with physical performance impairments and frailty. METHODS: The cohort included 736 patients with hematologic malignancies who underwent BMT at an age ≥ 60 years at 1 of 3 transplant centers between 1974 and 2014 and survived ≥2 years after BMT; 183 unaffected siblings also participated. Study participants reported on 4 pain domains (nonminor everyday pain, moderate to severe bodily pain, prolonged pain, and moderate to extreme pain interference), and the presence of 1 or more domains was indicative of a severe and/or life-interfering pain composite variable. RESULTS: Overall, 39.4% of the BMT survivors reported severe pain with 2.6-fold greater odds of reporting pain in comparison with sibling controls. Among BMT recipients, those with less education, lower incomes, and active chronic graft-versus-host disease had higher odds of reporting pain. In multivariable analyses, BMT survivors with pain were more likely to have impaired physical performance and were more likely to meet the frailty criteria. BMT survivors reported higher use of pain medications (17.8% vs 9.3%) and opioid pain medications (6.5% vs 2.2%) in comparison with sibling controls. CONCLUSIONS: Nearly 40% of older BMT survivors who were followed for a median of 5 years after BMT reported pain, and BMT survivors had 2.6-fold higher odds of reporting severe, nonminor or life-interfering pain in comparison with siblings.

Late mortality after autologous blood or marrow transplantation in childhood: a Blood or Marrow Transplant Survivor Study-2 report.

Autologous blood or marrow transplantation (BMT) is a curative option for several types of childhood cancer. However, there is little information regarding the risk of late mortality. We examined all-cause mortality, relapse-related mortality (RRM), and nonrelapse-related mortality (NRM) in 2-year survivors of autologous BMT performed before age 22 between 1980 and 2010 at 1 of 2 US transplant centers. Vital status information was collected using medical records, National Death Index, and Accurint databases. Overall survival was calculated using Kaplan-Meier techniques. Cumulative incidence of mortality used competing risk methods. Standardized mortality ratio (SMR) was calculated using age-, sex-, and calendar-specific mortality rates from Centers for Disease Control and Prevention. Cox regression analysis was used to determine predictors of all-cause late mortality. Among the 345 2-year survivors, 103 deaths were observed, yielding an overall survival of 70.3% 15 years post-BMT. The leading causes of death included primary disease (50.0%), subsequent neoplasm (21.4%), and infection (18.2%). Overall, the cohort was at a 22-fold increased risk of late mortality (SMR, 21.8; 95% CI, 17.9-26.3), compared with the general population. Mortality rates remained elevated among the 10-year survivors (SMR, 20.6; 95% CI, 9.9-37.2) but approached those of the general population ≥15 years post-BMT. The 10-year cumulative incidence of RRM (14.3%) exceeded that of NRM (10.4%). The 10-year cumulative mortality rate declined over time (<1990, 35.1%; 1990-1999, 25.6%; 2000-2010, 21.8%; P = .05). In conclusion, childhood autologous BMT recipients have an increased risk of late mortality, compared with the general population. The late mortality rates have declined over the past 3 decades.

Venous Thromboembolism in Autologous Blood or Marrow Transplantation Survivors: A Report from the Blood or Marrow Transplant Survivor Study.

Hemostatic complications are commonly encountered in blood or marrow transplantation (BMT) recipients, increasing their morbidity and mortality and are well described in the immediate post-transplantation period. The risk of venous thromboembolism (VTE) in long-term survivors of autologous BMT has not been studied previously. Patients who underwent autologous BMT between January 1, 1974, and December 31, 2010 for a hematologic malignancy, lived 2 years or more after transplantation, and were age ≥18 years were surveyed for long-term outcomes. The median duration of follow-up was 9.8 years (interquartile range, 6.4 to 14.3 years). We analyzed the risk of VTE in 820 autologous BMT recipients who survived for ≥2 years, compared with 644 siblings. BMT survivors were at a 2.6-fold higher risk of VTE compared with siblings (95% confidence interval [CI], 1.6 to 4.4; P =.0004), after adjusting for sociodemographic characteristics. Conditional on surviving for ≥2 years after BMT, the mean cumulative incidence of VTE was 3.9 ± .8% at 5 years and 6.1 ± 1.1% at 10 years. A diagnosis of plasma cell disorder (hazard ratio [HR], 2.37; 95% CI, 1.3 to 4.2; P = .004) and annual household income ≤$50,000 (HR, 2.02; 95% CI, 1.2 to 3.6; P = .015) were associated with increased VTE risk. Our data indicate that autologous BMT survivors are at elevated risk for developing late-occurring VTE. The development of risk prediction models to identify autologous BMT survivors at greatest risk for VTE and thromboprophylaxis may help decrease the morbidity and mortality associated with VTE.

Late Mortality after Allogeneic Bone Marrow Transplantation in Childhood for Bone Marrow Failure Syndromes and Severe Aplastic Anemia.

Children with bone marrow failure syndromes and severe aplastic anemia (SAA) are treated with allogeneic blood or marrow transplantation (BMT). However, there is a paucity of studies examining late mortality risk after allogeneic BMT performed in childhood for bone marrow failure syndromes and SAA and evaluating how this risk differs between these diseases. We investigated cause-specific late mortality in 2-year survivors of allogeneic BMT for bone marrow failure syndromes and SAA performed before age 22years between 1974 and 2010 at 2 US transplantation centers. Vital status information was collected from medical records, the National Death Index, and Accurint databases. Overall survival was calculated using Kaplan-Meier techniques. The standardized mortality ratio (SMR) was calculated using age- sex-, and calendar-specific mortality rates from the Centers for Disease Control and Prevention. Among the 2-year survivors of bone marrow failure syndromes (n = 120) and SAA (n = 147), there were 15 and 19 deaths, respectively, yielding an overall survival of 86.4% for bone marrow failure syndromes and 93.1% for SAA at 15years post-BMT. Compared with the general population, patients with bone marrow failure syndromes were at a higher risk for premature death (SMR, 22.7; 95% CI, 13.1 to 36.2) compared with those with SAA (SMR, 4.5; 95% CI, 2.8 to 7.0) (P < .0001). The elevated relative risk persisted at ≥15years after BMT for both diseases. The hazard of all-cause late mortality was 2.9-fold (95% CI, 1.1 to 7.3) higher in patients with bone marrow failure syndromes compared with those with SAA. The high late mortality risk in recipients of allogeneic BMT in childhood for bone marrow failure syndromes calls for intensified life-long follow-up.

Late Mortality after Allogeneic Blood or Marrow Transplantation for Inborn Errors of Metabolism: A Report from the Blood or Marrow Transplant Survivor Study-2 (BMTSS-2).

Allogeneic blood or marrow transplantation (BMT) is currently considered the standard of care for patients with specific inborn errors of metabolism (IEM). However, there is a paucity of studies describing long-term survival and cause-specific late mortality after BMT in these patients with individual types of IEM. We studied 273 patients who had survived ≥2 years after allogeneic BMT for IEM performed between 1974 and 2014. The most prevalent IEM in our cohort were X-linked adrenoleukodystrophy (ALD; 37.3%), Hurler syndrome (35.1%), and metachromatic leukodystrophy (MLD; 10.2%). Conditional on surviving ≥2 years after BMT, the overall survival for the entire cohort was 85.5 ± 2.4% at 10 years and 73.5 ± 3.7% at 20 years. The cohort had a 29-fold increased risk of late death compared with an age- and sex-matched cohort from the general US population (95% CI, 22- to 38-fold). The increased relative mortality was highest in the 2- to 5-year period after BMT (standardized mortality ratio [SMR], 207; 95% confidence interval [CI], 130 to 308) and declined with increasing time from BMT, but remained elevated for ≥21 years after BMT (SMR, 9; 95% CI, 4 to 18). Sequelae from the progression of primary disease were the most common causes of late mortality in this cohort (76%). The use of T cell-depleted grafts in patients with ALD and Hurler syndrome was a risk factor for late mortality. Younger age at BMT and use of busulfan and cyclosporine were protective in patients with Hurler syndrome. Our findings demonstrate relatively favorable overall survival in ≥2-year survivors of allogeneic BMT for IEM, although primary disease progression continues to be responsible for the majority of late deaths.

Risk of venous thromboembolism in patients with non-Hodgkin lymphoma surviving blood or marrow transplantation.

BACKGROUND: Patients with non-Hodgkin lymphoma (NHL) have an increased risk of venous thromboembolism (VTE), particularly when they are receiving treatment. Blood or marrow transplantation (BMT) is recommended for relapsed/refractory NHL, and the risk of VTE after these patients undergo BMT is uncertain. METHODS: Patients with NHL who survived 2 years or longer after BMT were surveyed for long-term health outcomes, including VTE. The median follow-up was 8.1 years (interquartile range, 5.6-12.9 years). The risk of VTE in 734 patients with NHL versus 897 siblings without a history of cancer and the risk factors associated with VTE were analyzed. RESULTS: BMT survivors of NHL were at increased risk for VTE in comparison with siblings (odds ratio for allogeneic BMT survivors, 4.61; P < .0001; odds ratio for autologous BMT survivors, 1.75; P = .035). The cumulative incidence of VTE was 6.3% ± 0.9% at 5 years after BMT and 8.1% ± 1.1% at 10 years after BMT. In allogeneic BMT recipients, an increased body mass index (BMI; hazard ratio [HR] for BMI of 25-30 kg/m2 , 3.52; 95% confidence interval [CI], 1.43-8.64; P = .006; HR for BMI > 30 kg/m2 , 3.44; 95% CI, 1.15-10.23; P = .027) and a history of chronic graft-versus-host disease (HR, 3.33; 95% CI, 1.59-6.97; P = .001) were associated with an increased risk of VTE. Among autologous BMT recipients, a diagnosis of coronary artery disease (HR, 5.94; 95% CI, 1.7-20.71; P = .005) and prior treatment with carmustine (HR, 4.91; 95% CI, 1.66-14.51; P = .004) were associated with increased VTE risk. CONCLUSIONS: Patients with NHL who survive BMT are at risk for developing late occurring VTE, and ongoing vigilance for this complication is required. Future studies assessing the role of thromboprophylaxis in high-risk patients with NHL are needed.

Late mortality after bone marrow transplant for chronic myelogenous leukemia in the context of prior tyrosine kinase inhibitor exposure: A Blood or Marrow Transplant Survivor Study (BMTSS) report.

BACKGROUND: Late mortality was investigated in patients with chronic myelogenous leukemia (CML) who underwent blood or bone marrow transplant (BMT) with or without prior tyrosine kinase inhibitor (TKI) therapy. METHODS: By using data from the Blood or Marrow Transplant Survivor Study, the authors examined late mortality in 447 patients with CML who underwent BMT between 1974 and 2010, conditional on surviving ≥2 years post-BMT. For vital status information, the medical records, the National Death Index, and the Accurint database were used. Standardized mortality ratios (SMRs) were calculated using general population age-specific, sex-specific, and calendar-specific mortality rates. Kaplan-Meier techniques and Cox regression were used for all-cause mortality analyses. Cumulative incidence and proportional subdistribution hazards models for competing risks were used for cause-specific mortality analyses. RESULTS: The 10-year overall survival rate was 65.7% and 73% for those who underwent transplant with and without pre-BMT exposure to TKI therapy, respectively. Patients who underwent transplant with and without pre-BMT TKI experienced SMRs of 6.4 and 6.4, respectively (P = .8); and the SMRs were 11.6 and 8.1, respectively, for those with high-risk disease (P = .2). Independent predictors of non-CML-related mortality included chronic graft-versus-host disease (hazard ratio [HR], 2.8; 95% CI, 1.8-4.4) and busulfan/cyclophosphamide conditioning (HR, 0.5; 95% CI, 0.3-0.9; reference, total body irradiation/cyclophosphamide conditioning). The 20-year cumulative incidence of CML-related and non-CML-related mortality was 6% and 36%, respectively, for the entire cohort. Both CML-related mortality (HR, 1.0; 95% CI, 0.1-12.6) and non-CML-related mortality (HR, 1.3; 95% CI, 0.6-3.1) were comparable for those with and without pre-BMT TKI therapy. CONCLUSIONS: The similar late mortality experienced by patients with CML who undergo transplantation with or without pre-BMT TKIs suggests that allogeneic BMT can be considered in the context of TKI intolerance or nonadherence. The prevention of post-BMT non-CML-related mortality could favorably affect long-term survival.

In vivo overexpression of synaptogyrin-3 promotes striatal synaptic dopamine uptake in LRRK2R1441G mutant mouse model of Parkinson's disease.

BACKGROUND: Leucine-rich repeat kinase 2 (LRRK2) mutation is a common genetic risk factor of Parkinson's disease (PD). Presynaptic dysfunction is an early pathogenic event associated with dopamine (DA) dysregulation in striatum of the brain. DA uptake activity of DA uptake transporter (DAT) affects synaptic plasticity and motor and non-motor behavior. Synaptogyrin-3 (SYNGR3) is part of the synaptogyrin family, especially abundant in brain. Previous in vitro studies demonstrated interaction between SYNGR3 and DAT. Reduced SYNGR3 expression was observed in human PD brains with unclear reasons. METHODS: Here, we further explored whether inducing SYNGR3 expression can influence (i) cellular DA uptake using differentiated human SH-SY5Y neuronal cells, (ii) striatal synaptosomal DA uptake in a mutant LRRK2R1441G  knockin mouse model of PD, and (iii) innate rodent behavior using the marble burying test. RESULTS: Young LRRK2 mutant mice exhibited significantly lower SYNGR3 levels in striatum compared to age-matched wild-type (WT) controls, resembling level in aged WT mice. SYNGR3 is spatially co-localized with DAT at striatal presynaptic terminals, visualized by immuno-gold transmission electron microscopy and immunohistochemistry. Their protein-protein interaction was confirmed by co-immunoprecipitation. Transient overexpression of SYNGR3 in differentiated SH-SY5Y cells increased cellular DA uptake activity without affecting total DAT levels. Inducing SYNGR3 overexpression by adeno-associated virus-7 (AAV7) injection in vivo into striatum increased ex vivo synaptosomal DA uptake in LRRK2 mutant mice and improved their innate marble burying behavior. CONCLUSION: Brain SYNGR3 expression may be an important determinant to striatal DA homeostasis and synaptic function. Our preliminary behavioral test showed improved innate behavior after SYNGR3 overexpression in LRRK2 mutant mice, advocating further studies to determine the influence of SYNGR3 in the pathophysiology of DA neurons in PD.

Single-nucleotide polymorphism of transient axonal glycoprotein-1 and its correlation with clinical features and prognosis in chronic inflammatory demyelinating polyneuropathy.

The single-nucleotide polymorphism (SNP) rs2275697 in the transient axonal glycoprotein-1 (TAG-1) gene was reported to be associated with responsiveness to intravenous immunoglobulin (IVIG) treatment in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). However, it is not known if this SNP is associated with long-term prognosis. We examined the case records of 32 Chinese CIDP patients. The overall response rate to IVIG, prednisolone, or plasmapheresis was 83%. After 5.4 years, 57% of patients were on maintenance immunotherapy. Patients with higher modified Rankin score and more prolonged distal motor latencies in the upper limbs on presentation had a higher risk (odds ratio [OR] 3.86, 95% confidence interval [CI] 1.23-12.11 and OR 1.04, 95% CI 1.01-1.07, respectively) of being on maintenance immunotherapy. Blood samples from 24 patients and 147 controls were examined for their genotypes of four non-synonymous SNPs (rs41264871, rs36074532, rs5611135, and rs2275697) in the coding region of TAG-1. The G allelic frequency of rs2275697 was similar between CIDP patients and controls (56% and 50%, respectively) and was not associated with treatment responsiveness, treatment dependence, disability, or mortality.

LRRK2, GBA and their interaction in the regulation of autophagy: implications on therapeutics in Parkinson's disease.

Mutations in leucine-rich repeat kinase 2 (LRRK2) and glucocerebrosidase (GBA) represent two most common genetic causes of Parkinson's disease (PD). Both genes are important in the autophagic-lysosomal pathway (ALP), defects of which are associated with α-synuclein (α-syn) accumulation. LRRK2 regulates macroautophagy via activation of the mitogen activated protein kinase/extracellular signal regulated protein kinase (MAPK/ERK) kinase (MEK) and the calcium-dependent adenosine monophosphate (AMP)-activated protein kinase (AMPK) pathways. Phosphorylation of Rab GTPases by LRRK2 regulates lysosomal homeostasis and endosomal trafficking. Mutant LRRK2 impairs chaperone-mediated autophagy, resulting in α-syn binding and oligomerization on lysosomal membranes. Mutations in GBA reduce glucocerebrosidase (GCase) activity, leading to glucosylceramide accumulation, α-syn aggregation and broad autophagic abnormalities. LRRK2 and GBA influence each other: GCase activity is reduced in LRRK2 mutant cells, and LRRK2 kinase inhibition can alter GCase activity in GBA mutant cells. Clinically, LRRK2 G2019S mutation seems to modify the effects of GBA mutation, resulting in milder symptoms than those resulting from GBA mutation alone. However, dual mutation carriers have an increased risk of PD and earlier age of onset compared with single mutation carriers, suggesting an additive deleterious effect on the initiation of PD pathogenic processes. Crosstalk between LRRK2 and GBA in PD exists, but its exact mechanism is unclear. Drugs that inhibit LRRK2 kinase or activate GCase are showing efficacy in pre-clinical models. Since LRRK2 kinase and GCase activities are also altered in idiopathic PD (iPD), it remains to be seen if these drugs will be useful in disease modification of iPD.

Long-term inhibition of mutant LRRK2 hyper-kinase activity reduced mouse brain α-synuclein oligomers without adverse effects.

Parkinson's disease (PD) is characterized by dopaminergic neurodegeneration in nigrostriatal and cortical brain regions associated with pathogenic α-synuclein (αSyn) aggregate/oligomer accumulation. LRRK2 hyperactivity is a disease-modifying therapeutic target in PD. However, LRRK2 inhibition may be associated with peripheral effects, albeit with unclear clinical consequences. Here, we significantly reduced αSyn oligomer accumulation in mouse striatum through long-term LRRK2 inhibition using GNE-7915 (specific brain-penetrant LRRK2 inhibitor) without causing adverse peripheral effects. GNE-7915 concentrations in wild-type (WT) mouse sera and brain samples reached a peak at 1 h, which gradually decreased over 24 h following a single subcutaneous (100 mg/kg) injection. The same dose in young WT and LRRK2R1441G mutant mice significantly inhibited LRRK2 kinase activity (Thr73-Rab10 and Ser106-Rab12 phosphorylation) in the lung, which dissipated by 72 h post-injection. 14-month-old mutant mice injected with GNE-7915 twice weekly for 18 weeks (equivalent to ~13 human years) exhibited reduced striatal αSyn oligomer and cortical pSer129-αSyn levels, correlating with inhibition of LRRK2 hyperactivity in brain and lung to WT levels. No GNE-7915-treated mice showed increased mortality or morbidity. Unlike reports of abnormalities in lung and kidney at acute high doses of LRRK2 inhibitors, our GNE-7915-treated mice did not exhibit swollen lamellar bodies in type II pneumocytes or abnormal vacuolation in the kidney. Functional and histopathological assessments of lung, kidney and liver, including whole-body plethysmography, urinary albumin-creatinine ratio (ACR), serum alanine aminotransferase (ALT) and serum interleukin-6 (inflammatory marker) did not reveal abnormalities after long-term GNE-7915 treatment. Long-term inhibition of mutant LRRK2 hyper-kinase activity to physiological levels presents an efficacious and safe disease-modifying therapy to ameliorate synucleinopathy in PD.

Late-occurring venous thromboembolism in allogeneic blood or marrow transplant survivors: a BMTSS-HiGHS2 risk model.

Allogeneic blood or marrow transplant (BMT) recipients are at risk for venous thromboembolism (VTE) because of high-intensity therapeutic exposures, comorbidities, and a proinflammatory state due to chronic graft-versus-host disease (GVHD). The long-term risk of VTE in allogeneic BMT survivors remains unstudied. Participants were drawn from the Blood or Marrow Transplant Survivor Study (BMTSS), a retrospective cohort study that included patients who underwent transplantation between 1974 and 2014 and survived ≥2 years after BMT. We analyzed the risk of VTE in 1554 2-year survivors of allogeneic BMT compared with 907 siblings. Using backward variable selection guided by minimizing Akaike information criterion, we created a prediction model for risk of late-occurring VTE. Allogeneic BMT survivors had a 7.3-fold higher risk of VTE compared with siblings (95% CI, 4.69-11.46; P < .0001). After a median follow-up of 11 years, conditional on surviving the first 2 years after BMT, the cumulative incidence of late-occurring VTE was 2.4% at 5 years, 4.9% at 10 years, and 7.1% at 20 years after BMT. The final model for VTE risk at 2 years post-BMT included History of stroke, chronic GVHD, Hypertension, Sex (male vs female) and Stem cell source (peripheral blood stem cells vs other) ("HiGHS2") (corrected C-statistics: 0.73; 95% CI = 0.67-0.79). This model was able to classify patients at high and low VTE risk (10-year cumulative incidence, 9.3% vs 2.4% respectively; P < .0001). The BMTSS HiGHS2 risk model when applied at 2 years post-BMT can be used to inform targeted prevention strategies for patients at high risk for late-occurring VTE.

Aberrant mitochondrial morphology and function associated with impaired mitophagy and DNM1L-MAPK/ERK signaling are found in aged mutant Parkinsonian LRRK2R1441G mice.

Mitochondrial dysfunction causes energy deficiency and nigrostriatal neurodegeneration which is integral to the pathogenesis of Parkinson disease (PD). Clearance of defective mitochondria involves fission and ubiquitin-dependent degradation via mitophagy to maintain energy homeostasis. We hypothesize that LRRK2 (leucine-rich repeat kinase 2) mutation disrupts mitochondrial turnover causing accumulation of defective mitochondria in aging brain. We found more ubiquitinated mitochondria with aberrant morphology associated with impaired function in aged (but not young) LRRK2R1441G knockin mutant mouse striatum compared to wild-type (WT) controls. LRRK2R1441G mutant mouse embryonic fibroblasts (MEFs) exhibited reduced MAP1LC3/LC3 activation indicating impaired macroautophagy/autophagy. Mutant MEFs under FCCP-induced (mitochondrial uncoupler) stress showed increased LC3-aggregates demonstrating impaired mitophagy. Using a novel flow cytometry assay to quantify mitophagic rates in MEFs expressing photoactivatable mito-PAmCherry, we found significantly slower mitochondria clearance in mutant cells. Specific LRRK2 kinase inhibition using GNE-7915 did not alleviate impaired mitochondrial clearance suggesting a lack of direct relationship to increased kinase activity alone. DNM1L/Drp1 knockdown in MEFs slowed mitochondrial clearance indicating that DNM1L is a prerequisite for mitophagy. DNM1L knockdown in slowing mitochondrial clearance was less pronounced in mutant MEFs, indicating preexisting impaired DNM1L activation. DNM1L knockdown disrupted mitochondrial network which was more evident in mutant MEFs. DNM1L-Ser616 and MAPK/ERK phosphorylation which mediate mitochondrial fission and downstream mitophagic processes was apparent in WT using FCCP-induced stress but not mutant MEFs, despite similar total MAPK/ERK and DNM1L levels. In conclusion, aberrant mitochondria morphology and dysfunction associated with impaired mitophagy and DNM1L-MAPK/ERK signaling are found in mutant LRRK2 MEFs and mouse brain.Abbreviations: ATP: adenosine triphosphate; BAX: BCL2-associated X protein; CDK1: cyclin-dependent kinase 1; CDK5: cyclin-dependent kinase 5; CQ: chloroquine; CSF: cerebrospinal fluid; DNM1L/DRP1: dynamin 1-like; ELISA: enzyme-linked immunosorbent assay; FACS: fluorescence-activated cell sorting; FCCP: carbonyl cyanide-4-(trifluoromethoxy)phenylhydrazone; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; LAMP2A: lysosomal-associated membrane protein 2A; LRRK2: leucine-rich repeat kinase 2; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MAPK1/ERK2: mitogen-activated protein kinase 1; MEF: mouse embryonic fibroblast; MFN1: mitofusin 1; MMP: mitochondrial membrane potential; PAmCherry: photoactivatable-mCherry; PD: Parkinson disease; PINK1: PTEN induced putative kinase 1; PRKN/PARKIN: parkin RBR E3 ubiquitin protein ligase; RAB10: RAB10, member RAS oncogene family; RAF: v-raf-leukemia oncogene; SNCA: synuclein, alpha; TEM: transmission electron microscopy; VDAC: voltage-dependent anion channel; WT: wild type; SQSTM1/p62: sequestosome 1.

Age-dependent accumulation of oligomeric SNCA/α-synuclein from impaired degradation in mutant LRRK2 knockin mouse model of Parkinson disease: role for therapeutic activation of chaperone-mediated autophagy (CMA).

Parkinson disease (PD) is an age-related neurodegenerative disorder associated with misfolded SNCA/α-synuclein accumulation in brain. Impaired catabolism of SNCA potentiates formation of its toxic oligomers. LRRK2 (leucine-rich repeat kinase-2) mutations predispose to familial and sporadic PD. Mutant LRRK2 perturbs chaperone-mediated-autophagy (CMA) to degrade SNCA. We showed greater age-dependent accumulation of oligomeric SNCA in striatum and cortex of aged LRRK2R1441G knockin (KI) mice, compared to age-matched wildtype (WT) by 53% and 31%, respectively. Lysosomal clustering and accumulation of CMA-specific LAMP2A and HSPA8/HSC70 proteins were observed in aged mutant striatum along with increased GAPDH (CMA substrate) by immunohistochemistry of dorsal striatum and flow cytometry of ventral midbrain cells. Using our new reporter protein clearance assay, mutant mouse embryonic fibroblasts (MEFs) expressing either SNCA or CMA recognition 'KFERQ'-like motif conjugated with photoactivated-PAmCherry showed slower cellular clearance compared to WT by 28% and 34%, respectively. However, such difference was not observed after the 'KFERQ'-motif was mutated. LRRK2 mutant MEFs exhibited lower lysosomal degradation than WT indicating lysosomal dysfunction. LAMP2A-knockdown reduced total lysosomal activity and clearance of 'KFERQ'-substrate in WT but not in mutant MEFs, indicating impaired CMA in the latter. A CMA-specific activator, AR7, induced neuronal LAMP2A transcription and lysosomal activity in MEFs. AR7 also attenuated the progressive accumulation of both intracellular and extracellular SNCA oligomers in prolonged cultures of mutant cortical neurons (DIV21), indicating that oligomer accumulation can be suppressed by CMA activation. Activation of autophagic pathways to reduce aged-related accumulation of pathogenic SNCA oligomers is a viable disease-modifying therapeutic strategy for PD.Abbreviations: 3-MA: 3-methyladenine; AR7: 7-chloro-3-(4-methylphenyl)-2H-1,4-benzoxazine; CMA: chaperone-mediated autophagy; CQ: chloroquine; CSF: cerebrospinal fluid; DDM: n-dodecyl ß-D-maltoside; DIV: days in vitro; ELISA: enzyme-linked immunosorbent assay; FACS: fluorescence-activated cell sorting; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GWAS: genome-wide association studies; HSPA8/HSC70: heat shock protein 8; KFERQ: CMA recognition pentapeptide; KI: knockin; LAMP1: lysosomal-associated membrane protein 1; LAMP2A: lysosomal-associated membrane protein 2A; LDH: lactate dehydrogenase; LRRK2: leucine-rich repeat kinase 2; MEF: mouse embryonic fibroblast; NDUFS4: NADH:ubiquinone oxidoreductase core subunit S4; NE: novel epitope; PD: Parkinson disease; RARA/RARα: retinoic acid receptor, alpha; SNCA: synuclein, alpha; TUBB3/TUJ1: tubulin, beta 3 class III; WT: wild-type.

Total Body Irradiation and Risk of Breast Cancer After Blood or Marrow Transplantation: A Blood or Marrow Transplantation Survivor Study Report.

PURPOSE: To examine the association between total body irradiation (TBI) and subsequent breast cancer in women treated with blood or marrow transplantation (BMT) for hematologic malignancies. PATIENTS AND METHODS: Participants were drawn from the BMT Survivor Study (BMTSS), a retrospective cohort study that included patients who underwent transplantation between 1974 and 2014 and survived for ≥ 2 years after BMT. Patients with pre-BMT chest radiation or a history of breast cancer were excluded. Participants completed the BMTSS survey, which included details regarding breast cancer diagnosis. Subsequent breast cancer was confirmed by pathology report review or physician notes. Cox proportional hazards models assessed the association between TBI and subsequent breast cancer. Standardized incidence ratios were calculated to determine the excess risk of subsequent breast cancer compared with that in the general population. RESULTS: A total of 1,464 female BMT survivors (allogeneic: n = 788; autologous: n = 676) participated, with a median follow-up of 9.3 years from BMT. TBI was used in 660 patients (46%). Thirty-seven women developed subsequent breast cancer (allogeneic: n = 19; autologous: n = 18). Multivariable analysis revealed that exposure to TBI was associated with an increased risk of subsequent breast cancer among allogeneic BMT survivors (hazard ratio [HR], 3.7 [95% CI, 1.2 to 11.8]; P = .03) and autologous BMT survivors (HR, 2.6 [95% CI, 1.0 to 6.8]; P = .048). Pre-BMT exposure to alkylating agents was associated with an increased risk of subsequent breast cancer among autologous BMT survivors (HR, 3.3 [95% CI, 1.0 to 9.0]; P = .05). Compared with that in the general population, exposure to TBI at age < 30 years was associated with a 4.4-fold higher risk of subsequent breast cancer in allogeneic BMT survivors and a 4.6-fold higher risk in autologous BMT survivors. CONCLUSION: The association between TBI and subsequent breast cancer, especially among those exposed at a young age, as well as pre-BMT exposure to alkylating agents, should inform breast cancer screening for early detection.

Assessment of Late Mortality Risk After Allogeneic Blood or Marrow Transplantation Performed in Childhood.

Importance: Allogeneic blood or marrow transplantation (BMT) is a curative option for malignant and nonmalignant diseases of childhood. However, little is known about trends in cause-specific late mortality in this population during the past 3 decades. Objectives: To examine cause-specific late mortality among individuals who have lived 2 years or more after allogeneic BMT performed in childhood and whether rates of late mortality have changed over time. Design, Setting, and Participants: A retrospective cohort study was conducted of individuals who lived 2 years or more after undergoing allogeneic BMT performed in childhood between January 1, 1974, and December 31, 2010. The end of follow-up was December 31, 2016. Exposure: Allogeneic BMT performed in childhood. Main Outcomes and Measures: All-cause mortality, relapse-related mortality, and non-relapse-related mortality. Data on vital status and causes of death were collected using medical records, the National Death Index Plus Program, and Accurint databases. Results: Among 1388 individuals (559 females and 829 males) who lived 2 years or more after allogeneic BMT performed in childhood, the median age at transplantation was 14.6 years (range, 0-21 years). In this cohort, there was a total of 295 deaths, yielding an overall survival rate of 79.3% at 20 years after BMT. The leading causes of death were infection and/or chronic graft-vs-host disease (121 of 244 [49.6%]), primary disease (60 of 244 [24.6%]), and subsequent malignant neoplasms (45 of 244 [18.4%]). Overall, the cohort had a 14.4-fold increased risk for death (95% CI, 12.8-16.1) compared with the general population (292 deaths observed; 20.3 deaths expected). Relative mortality remained elevated at 25 years or more after BMT (standardized mortality ratio, 2.9; 95% CI, 2.0-4.1). The absolute excess risk for death from any cause was 12.0 per 1000 person-years (95% CI, 10.5-13.5). The cumulative incidence of non-relapse-related mortality exceeded that of relapse-related mortality throughout follow-up. The 10-year cumulative incidence of late mortality decreased over time (before 1990, 18.9%; 1990-1999, 12.8%; 2000-2010, 10.9%; P = .002); this decrease remained statistically significant after adjusting for demographic and clinical factors (referent group: <1990; 1990-1999: hazard ratio, 0.64; 95% CI, 0.47-0.89; P = .007; 2000-2010: hazard ratio, 0.49; 95% CI, 0.31-0.76; P = .002; P < .001 for trend). Conclusions and Relevance: Late mortality among children undergoing allogeneic BMT has decreased during the past 3 decades. However, these patients remain at an elevated risk of late mortality even 25 years or more after transplantation when compared with the general population, necessitating lifelong follow-up.