Browsing by Author "Gadalla, Shahinaz M."
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Item Bile acid synthesis, modulation, and dementia: A metabolomic, transcriptomic, and pharmacoepidemiologic study(PLOS, 2021-05-27) Varma, Vijay R.; Wang, Youjin; An, Yang; Varma, Sudhir; Bilgel, Murat; Doshi, Jimit; Legido-Quigley, Cristina; Delgado, João C.; Oommen, Anup M.; Roberts, Jackson A.; Wong, Dean F.; Davatzikos, Christos; Resnick, Susan M.; Troncoso, Juan C.; Pletnikova, Olga; O’Brien, Richard; Hak, Eelko; Baak, Brenda N.; Pfeiffer, Ruth; Baloni, Priyanka; Mohmoudiandehkordi, Siamak; Nho, Kwangsik; Kaddurah-Daouk, Rima; Bennett, David A.; Gadalla, Shahinaz M.; Thambisetty, Madhav; Radiology and Imaging Sciences, School of MedicineBackground: While Alzheimer disease (AD) and vascular dementia (VaD) may be accelerated by hypercholesterolemia, the mechanisms underlying this association are unclear. We tested whether dysregulation of cholesterol catabolism, through its conversion to primary bile acids (BAs), was associated with dementia pathogenesis. Methods and findings: We used a 3-step study design to examine the role of the primary BAs, cholic acid (CA), and chenodeoxycholic acid (CDCA) as well as their principal biosynthetic precursor, 7α-hydroxycholesterol (7α-OHC), in dementia. In Step 1, we tested whether serum markers of cholesterol catabolism were associated with brain amyloid accumulation, white matter lesions (WMLs), and brain atrophy. In Step 2, we tested whether exposure to bile acid sequestrants (BAS) was associated with risk of dementia. In Step 3, we examined plausible mechanisms underlying these findings by testing whether brain levels of primary BAs and gene expression of their principal receptors are altered in AD. Step 1: We assayed serum concentrations CA, CDCA, and 7α-OHC and used linear regression and mixed effects models to test their associations with brain amyloid accumulation (N = 141), WMLs, and brain atrophy (N = 134) in the Baltimore Longitudinal Study of Aging (BLSA). The BLSA is an ongoing, community-based cohort study that began in 1958. Participants in the BLSA neuroimaging sample were approximately 46% male with a mean age of 76 years; longitudinal analyses included an average of 2.5 follow-up magnetic resonance imaging (MRI) visits. We used the Alzheimer's Disease Neuroimaging Initiative (ADNI) (N = 1,666) to validate longitudinal neuroimaging results in BLSA. ADNI is an ongoing, community-based cohort study that began in 2003. Participants were approximately 55% male with a mean age of 74 years; longitudinal analyses included an average of 5.2 follow-up MRI visits. Lower serum concentrations of 7α-OHC, CA, and CDCA were associated with higher brain amyloid deposition (p = 0.041), faster WML accumulation (p = 0.050), and faster brain atrophy mainly (false discovery rate [FDR] p = <0.001-0.013) in males in BLSA. In ADNI, we found a modest sex-specific effect indicating that lower serum concentrations of CA and CDCA were associated with faster brain atrophy (FDR p = 0.049) in males.Step 2: In the Clinical Practice Research Datalink (CPRD) dataset, covering >4 million registrants from general practice clinics in the United Kingdom, we tested whether patients using BAS (BAS users; 3,208 with ≥2 prescriptions), which reduce circulating BAs and increase cholesterol catabolism, had altered dementia risk compared to those on non-statin lipid-modifying therapies (LMT users; 23,483 with ≥2 prescriptions). Patients in the study (BAS/LMT) were approximately 34%/38% male and with a mean age of 65/68 years; follow-up time was 4.7/5.7 years. We found that BAS use was not significantly associated with risk of all-cause dementia (hazard ratio (HR) = 1.03, 95% confidence interval (CI) = 0.72-1.46, p = 0.88) or its subtypes. We found a significant difference between the risk of VaD in males compared to females (p = 0.040) and a significant dose-response relationship between BAS use and risk of VaD (p-trend = 0.045) in males.Step 3: We assayed brain tissue concentrations of CA and CDCA comparing AD and control (CON) samples in the BLSA autopsy cohort (N = 29). Participants in the BLSA autopsy cohort (AD/CON) were approximately 50%/77% male with a mean age of 87/82 years. We analyzed single-cell RNA sequencing (scRNA-Seq) data to compare brain BA receptor gene expression between AD and CON samples from the Religious Orders Study and Memory and Aging Project (ROSMAP) cohort (N = 46). ROSMAP is an ongoing, community-based cohort study that began in 1994. Participants (AD/CON) were approximately 56%/36% male with a mean age of 85/85 years. In BLSA, we found that CA and CDCA were detectable in postmortem brain tissue samples and were marginally higher in AD samples compared to CON. In ROSMAP, we found sex-specific differences in altered neuronal gene expression of BA receptors in AD. Study limitations include the small sample sizes in the BLSA cohort and likely inaccuracies in the clinical diagnosis of dementia subtypes in primary care settings. Conclusions: We combined targeted metabolomics in serum and amyloid positron emission tomography (PET) and MRI of the brain with pharmacoepidemiologic analysis to implicate dysregulation of cholesterol catabolism in dementia pathogenesis. We observed that lower serum BA concentration mainly in males is associated with neuroimaging markers of dementia, and pharmacological lowering of BA levels may be associated with higher risk of VaD in males. We hypothesize that dysregulation of BA signaling pathways in the brain may represent a plausible biologic mechanism underlying these results. Together, our observations suggest a novel mechanism relating abnormalities in cholesterol catabolism to risk of dementia.Item Impact of T Cell Dose on Outcome of T Cell-Replete HLA-Matched Allogeneic Peripheral Blood Stem Cell Transplantation(Elsevier, 2019) Saad, Ayman; Lamb, Lawrence; Wang, Tao; Hemmer, Michael T.; Spellman, Stephen; Couriel, Daniel; Alousi, Amin; Pidala, Joseph; Abdel-Azim, Hisham; Agrawal, Vaibhav; Aljurf, Mahmoud; Beitinjaneh, Amer M.; Bhatt, Vijaya Raj; Buchbinder, David; Byrne, Michael; Cahn, Jean-Yves; Cairo, Mitchell; Castillo, Paul; Chhabra, Saurabh; Diaz, Miguel Angel; Farhan, Shatha; Floisand, Yngvar; Frangoul, Hadar A.; Gadalla, Shahinaz M.; Gajewski, James; Gale, Robert Peter; Gandhi, Manish; Gergis, Usama; Hamilton, Betty Ky; Hematti, Peiman; Hildebrandt, Gerhard C.; Kamble, Rammurti T.; Kanate, Abraham S.; Khandelwal, Pooja; Lazaryn, Aleksandr; MacMillan, Margaret; Marks, David I.; Martino, Rodrigo; Mehta, Parinda A.; Nishihori, Taiga; Olsson, Richard F.; Patel, Sagar S.; Qayed, Muna; Rangarajan, Hemalatha G.; Reshef, Ran; Ringden, Olle; Savani, Bipin N.; Schouten, Harry C.; Schultz, Kirk R.; Seo, Sachiko; Shaffer, Brian C.; Solh, Melhem; Teshima, Takanori; Urbano-Ispizua, Alvaro; Verdonck, Leo F.; Vij, Ravi; Waller, Edmund K.; William, Basem; Wirk, Baldeep; Yared, Jean A.; Yu, Lolie C.; Arora, Mukta; Hashmi, Shahrukh; Medicine, School of MedicineData on whether the T cell dose of allogeneic peripheral blood stem cell (PBSC) products influences transplantation outcomes are conflicting. Using the Center for International Blood and Marrow Transplant Research database, we identified 2736 adult patients who underwent first allogeneic PBSC transplantation for acute leukemia or myelodysplastic syndrome between 2008 and 2014 using an HLA-matched sibling donor (MSD) or an 8/8-matched unrelated donor (MUD). We excluded ex vivo and in vivo T cell-depleted transplantations. Correlative analysis was performed between CD3+ T cell dose and the risk of graft-versus-host-disease (GVHD), relapse, nonrelapse mortality (NRM), disease-free survival (DFS), and overall survival (OS). Using maximum likelihood estimation, we identified CD3+ T cell dose cutoff that separated the risk of acute GVHD (aGVHD) grade II-IV in both the MSD and MUD groups. A CD3+ T cell dose cutoff of 14 × 107 cells/kg identified MSD/low CD3+ (n = 223) and MSD/high CD3+ (n = 1214), and a dose of 15 × 107 cells/kg identified MUD/low CD3+ (n = 197) and MUD/high CD3+ (n = 1102). On univariate analysis, the MSD/high CD3+ group had a higher cumulative incidence of day +100 aGVHD grade II-IV compared with the MSD/low CD3+ group (33% versus 25%; P = .009). There were no differences between the 2 groups in engraftment rate, risk of aGVHD grade III-IV or chronic GVHD (cGVHD), NRM, relapse, DFS, or OS. The MUD/high CD3+ group had a higher cumulative incidence of day +100 aGVHD grade II-IV compared with the MUD/low CD3+ group (49% versus 41%; P = .04). There were no differences between the 2 groups in engraftment rate, risk of severe aGVHD or cGVHD, NRM, relapse, DFS, or OS. Multivariate analysis of the MSD and MUD groups failed to show an association between CD3+ T cell dose and the risk of either aGVHD grade II-IV (P = .10 and .07, respectively) or cGVHD (P = .80 and .30, respectively). Subanalysis of CD4+ T cells, CD8+ T cells, and CD4+/CD8+ ratio failed to identify cutoff values predictive of transplantation outcomes; however, using the log-rank test, the sample size was suboptimal for identifying a difference at this cutoff cell dose. In this registry study, the CD3+ T cell dose of PBSC products did not influence the risk of aGVHD or cGVHD or other transplantation outcomes when using an MSD or an 8/8-matched MUD. Subset analyses of CD4+ and CD8+ T cell doses were not possible given our small sample size.Item Risk Factors for Graft-versus-Host Disease in Haploidentical Hematopoietic Cell Transplantation Using Post-Transplant Cyclophosphamide(Elsevier, 2020-08) Im, Annie; Rashidi, Armin; Wang, Tao; Hemmer, Michael; MacMillan, Margaret L.; Pidala, Joseph; Jagasia, Madan; Pavletic, Steven; Majhail, Navneet S.; Weisdorf, Daniel; Abdel-Azim, Hisham; Agrawal, Vaibhav; Al-Homsi, A. Samer; Aljurf, Mahmoud; Askar, Medhat; Auletta, Jeffery J.; Bashey, Asad; Beitinjaneh, Amer; Bhatt, Vijaya Raj; Byrne, Michael; Cahn, Jean-Yves; Cairo, Mitchell; Castillo, Paul; Cerny, Jan; Chhabra, Saurabh; Choe, Hannah; Ciurea, Stefan; Daly, Andrew; Perez, Miguel Angel Diaz; Farhadfar, Nosha; Gadalla, Shahinaz M.; Gale, Robert; Ganguly, Siddhartha; Gergis, Usama; Hanna, Rabi; Hematti, Peiman; Herzig, Roger; Hildebrandt, Gerhard C.; Lad, Deepesh P.; Lee, Catherine; Lehmann, Leslie; Lekakis, Lazaros; Kamble, Rammurti T.; Kharfan-Dabaja, Mohamed A.; Khandelwal, Pooja; Martino, Rodrigo; Murthy, Hemant S.; Nishihori, Taiga; O'Brien, Tracey A.; Olsson, Richard F.; Patel, Sagar S.; Perales, Miguel-Angel; Prestidge, Tim; Qayed, Muna; Romee, Rizwan; Schoemans, Hélène; Seo, Sachiko; Sharma, Akshay; Solh, Melhem; Strair, Roger; Teshima, Takanori; Urbano-Ispizua, Alvaro; Van der Poel, Marjolein; Vij, Ravi; Wagner, John L.; William, Basem; Wirk, Baldeep; Yared, Jean A.; Spellman, Steve R.; Arora, Mukta; Hamilton, Betty K.; Medicine, School of MedicinePost-transplant cyclophosphamide (PTCy) has significantly increased the successful use of haploidentical donors with a relatively low incidence of graft-versus-host disease (GVHD). Given its increasing use, we sought to determine risk factors for GVHD after haploidentical hematopoietic cell transplantation (haplo-HCT) using PTCy. Data from the Center for International Blood and Marrow Transplant Research on adult patients with acute myeloid leukemia, acute lymphoblastic leukemia, myelodysplastic syndrome, or chronic myeloid leukemia who underwent PTCy-based haplo-HCT (2013 to 2016) were analyzed and categorized into 4 groups based on myeloablative (MA) or reduced-intensity conditioning (RIC) and bone marrow (BM) or peripheral blood (PB) graft source. In total, 646 patients were identified (MA-BM = 79, MA-PB = 183, RIC-BM = 192, RIC-PB = 192). The incidence of grade 2 to 4 acute GVHD at 6 months was highest in MA-PB (44%), followed by RIC-PB (36%), MA-BM (36%), and RIC-BM (30%) (P = .002). The incidence of chronic GVHD at 1 year was 40%, 34%, 24%, and 20%, respectively (P < .001). In multivariable analysis, there was no impact of stem cell source or conditioning regimen on grade 2 to 4 acute GVHD; however, older donor age (30 to 49 versus <29 years) was significantly associated with higher rates of grade 2 to 4 acute GVHD (hazard ratio [HR], 1.53; 95% confidence interval [CI], 1.11 to 2.12; P = .01). In contrast, PB compared to BM as a stem cell source was a significant risk factor for the development of chronic GVHD (HR, 1.70; 95% CI, 1.11 to 2.62; P = .01) in the RIC setting. There were no differences in relapse or overall survival between groups. Donor age and graft source are risk factors for acute and chronic GVHD, respectively, after PTCy-based haplo-HCT. Our results indicate that in RIC haplo-HCT, the risk of chronic GVHD is higher with PB stem cells, without any difference in relapse or overall survival.Item Survival following allogeneic transplant in patients with myelofibrosis(American Society of Hematology, 2020-05-08) Gowin, Krisstina; Ballen, Karen; Ahn, Kwang Woo; Hu, Zhen-Huan; Ali, Haris; Arcasoy, Murat O.; Devlin, Rebecca; Coakley, Maria; Gerds, Aaron T.; Green, Michael; Gupta, Vikas; Hobbs, Gabriela; Jain, Tania; Kandarpa, Malathi; Komrokji, Rami; Kuykendall, Andrew T.; Luber, Kierstin; Masarova, Lucia; Michaelis, Laura C.; Patches, Sarah; Pariser, Ashley C.; Rampal, Raajit; Stein, Brady; Talpaz, Moshe; Verstovsek, Srdan; Wadleigh, Martha; Agrawal, Vaibhav; Aljurf, Mahmoud; Diaz, Miguel Angel; Avalos, Belinda R.; Bacher, Ulrike; Bashey, Asad; Beitinjaneh, Amer M.; Cerny, Jan; Chhabra, Saurabh; Copelan, Edward; Cutler, Corey S.; DeFilipp, Zachariah; Gadalla, Shahinaz M.; Ganguly, Siddhartha; Grunwald, Michael R.; Hashmi, Shahrukh K.; Kharfan-Dabaja, Mohamed A.; Kindwall-Keller, Tamila; Kröger, Nicolaus; Lazarus, Hillard M.; Liesveld, Jane L.; Litzow, Mark R.; Marks, David I.; Nathan, Sunita; Nishihori, Taiga; Olsson, Richard F.; Pawarod, Attaphol; Rowe, Jacob M.; Savani, Bipin N.; Savoie, Mary Lynn; Seo, Sachiko; Solh, Melhem; Tamari, Roni; Verdonck, Leo F.; Yared, Jean A.; Alyea, Edwin; Popat, Uday; Sobecks, Ronald; Scott, Bart L.; Nakamura, Ryotaro; Mesa, Ruben; Saber, Wael; Medicine, School of MedicineAllogeneic hematopoietic cell transplantation (HCT) is the only curative therapy for myelofibrosis (MF). In this large multicenter retrospective study, overall survival (OS) in MF patients treated with allogeneic HCT (551 patients) and without HCT (non-HCT) (1377 patients) was analyzed with Cox proportional hazards model. Survival analysis stratified by the Dynamic International Prognostic Scoring System (DIPSS) revealed that the first year of treatment arm assignment, due to upfront risk of transplant-related mortality (TRM), HCT was associated with inferior OS compared with non-HCT (non-HCT vs HCT: DIPSS intermediate 1 [Int-1]: hazard ratio [HR] = 0.26, P < .0001; DIPSS-Int-2 and higher: HR, 0.39, P < .0001). Similarly, in the DIPSS low-risk MF group, due to upfront TRM risk, OS was superior with non-HCT therapies compared with HCT in the first-year post treatment arm assignment (HR, 0.16, P = .006). However, after 1 year, OS was not significantly different (HR, 1.38, P = .451). Beyond 1 year of treatment arm assignment, an OS advantage with HCT therapy in Int-1 and higher DIPSS score patients was observed (non-HCT vs HCT: DIPSS-Int-1: HR, 2.64, P < .0001; DIPSS-Int-2 and higher: HR, 2.55, P < .0001). In conclusion, long-term OS advantage with HCT was observed for patients with Int-1 or higher risk MF, but at the cost of early TRM. The magnitude of OS benefit with HCT increased as DIPSS risk score increased and became apparent with longer follow-up.