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Role of trypsin and protease-activated receptor-2 in ovarian cancer
Kim, Kyu Kwang; Turner, Rachael; Khazan, Negar; Kodza, Arif; Jones, Aaron; Singh, Rakesh K; Moore, Richard G
Proteases have been implicated in the tumorigenesis and aggressiveness of a variety of cancer types. In fact, proteases have proven to be very clinically useful as tumor biomarkers in the blood of patients. Proteases are typically involved in complex systems of substrates, activators, and inhibitors, thus making our ability to establish their exact function in cancer more difficult. Trypsin, perhaps the most famous of proteases, has been shown to play a role in cancer progression, but its functional role in ovarian cancer has not been much studied. PAR2, a transmembrane receptor that is known to be activated by trypsin, has been reported to be associated with ovarian cancer. Here, we found that stimulation of ovarian cancer cell lines with trypsin or PAR2 activating peptide markedly increased MAPK signaling and cell proliferation. Additionally, HE4, a WAP-family glycoprotein and ovarian cancer biomarker, was found to inhibit trypsin degradation, thereby retaining its activity. Patient data seemed to support this phenomenon, as the serum of ovarian cancer patients with high HE4 expression, revealed significantly elevated trypsin levels. These data support the hypothesis that trypsin plays a tumorigenic role in ovarian cancer, which can be mediated by its receptor PAR2, and potentiated by HE4.
PMCID:7197761
PMID: 32365084
ISSN: 1932-6203
CID: 6035962
Cardiac allograft vasculopathy and graft failure in pediatric heart transplant recipients after rejection with severe hemodynamic compromise
Kleinmahon, Jake A; Gralla, Jane; Kirk, Richard; Auerbach, Scott R; Henderson, Heather T; Wallis, Gonzalo A; Ramakrishnan, Karthik; Singh, Rakesh K; Caldwell, Randall L; Savage, Andrew J; Everitt, Melanie D
BACKGROUND:Rejection with severe hemodynamic compromise (RSHC) carries a mortality risk approaching 50%. We aimed to identify current risk factors for RSHC and predictors of graft failure after RSHC. METHODS:Data from 3,259 heart transplant (HT) recipients between January 2005 and December 2015 in the Pediatric Heart Transplant Study (PHTS) were analyzed. Predictors for RSHC and outcome after RSHC were sought. Time to RSHC was analyzed using the Cox proportional hazards regression model. Cardiac allograft vasculopathy (CAV) after HT and CAV after RSHC were analyzed as time-dependent covariates. Timing of RSHC was analyzed as occurring before and after 4 years after RSHC. RESULTS:There were 309 patients (9.5%) with ≥ 1 RSHC episodes. In 143 patients with RSHC, the first episode was within 1 year after HT. Independent risk factors for RSHC were age 1 to 5 years at HT (hazard ratio [HR], 1.51; 95% confidence interval [CI], 1.04-2.18), age > 10 years at HT (HR, 1.83; 95% CI, 1.29-2.60), black race (HR, 1.64; 95% CI, 1.25-2.15), prior cardiac surgery (HR, 1.55; 95% CI, 1.03-2.31), ventricular assist device support at HT (HR, 1.65; 95% CI, 1.18-2.29), maintenance steroids (HR, 1.39; 95% CI, 1.06-1.82), and recipient on inotropes, pressors, or thyroid hormones (HR, 1.45; 95% CI, 1.09-1.94). Graft survival at 5 years after RSHC was 45.7%. RSHC was a greater risk factor for earlier CAV (HR, 7.78; 95% CI, 5.82-10.40) than other rejection types (HR, 2.31; 95% CI, 1.79-3.00). Patients with late RSHC, after 1 year after RSHC had increased risk of graft loss 4 years after RSHC (HR, 7.12; 95% CI, 2.18-23.22). The 5-year graft survival after RSHC was 50.5% for early RSHC and 39.0% for late RSHC. CONCLUSIONS:Mortality after RSHC is high in the current treatment era. Many patient risk factors for RSHC cannot be modified, including age, race, prior cardiac surgery, and ventricular assist device support. After RSHC, CAV is the only predictor of graft failure. Patients who have late RSHC fare worse than those who have RSHC within the first year after HT.
PMID: 30638837
ISSN: 1557-3117
CID: 4452512
Survival Without Cardiac Transplantation Among Children With Dilated Cardiomyopathy
Singh, Rakesh K; Canter, Charles E; Shi, Ling; Colan, Steven D; Dodd, Debra A; Everitt, Melanie D; Hsu, Daphne T; Jefferies, John L; Kantor, Paul F; Pahl, Elfriede; Rossano, Joseph W; Towbin, Jeffrey A; Wilkinson, James D; Lipshultz, Steven E
BACKGROUND:Studies of children with dilated cardiomyopathy (DCM) have suggested that improved survival has been primarily due to utilization of heart transplantation. OBJECTIVES/OBJECTIVE:This study sought to determine transplant-free survival for these children over 20 years and identify the clinical characteristics at diagnosis that predicted death. METHODS:Children <18 years of age with some type of DCM enrolled in the Pediatric Cardiomyopathy Registry were divided by year of diagnosis into an early cohort (1990 to 1999) and a late cohort (2000 to 2009). Competing risks and multivariable modeling were used to estimate the cumulative incidence of death, transplant, and echocardiographic normalization by cohort and to identify the factors associated with death. RESULTS:Of 1,953 children, 1,199 were in the early cohort and 754 were in the late cohort. Most children in both cohorts had idiopathic DCM (64% vs. 63%, respectively). Median age (1.6 vs. 1.7 years), left ventricular end-diastolic z-scores (+4.2 vs. +4.2), and left ventricular fractional shortening (16% vs. 17%) at diagnosis were similar between cohorts. Although the rates of echocardiographic normalization (30% and 27%) and heart transplantation (24% and 24%) were similar, the death rate was higher in the early cohort than in the late cohort (18% vs. 9%; p = 0.04). Being in the early cohort (hazard ratio: 1.4; 95% confidence interval: 1.04 to 1.9; p = 0.03) independently predicted death. CONCLUSIONS:Children with DCM have improved survival in the more recent era. This appears to be associated with factors other than heart transplantation, which was equally prevalent in both eras. (Pediatric Cardiomyopathy Registry [PCMR]; NCT00005391).
PMID: 29169474
ISSN: 1558-3597
CID: 4452502
Fontan Patient Survival After Pediatric Heart Transplantation Has Improved in the Current Era
Simpson, Kathleen E; Pruitt, Elizabeth; Kirklin, James K; Naftel, David C; Singh, Rakesh K; Edens, R Erik; Barnes, Aliessa P; Canter, Charles E
BACKGROUND:Historically, patients with a prior Fontan procedure for complex congenital heart disease (CHD) have been considered at higher risk for death after heart transplant (HT) compared with other HT transplant candidates. With the overall trend of improved survival of pediatric HT recipients, it is unclear of Fontan patient post-HT survival has also improved in the current era. METHODS:Data from the Pediatric Heart Transplant Study database for Fontan patients who underwent HT was compared between the early era (1993 to 2006, n = 150) and late era (2007 to 2014, n = 252). Post-HT survival and pre-HT characteristics were compared among eras and also with non-Fontan CHD patients. RESULTS:At time of HT, Fontan patients in the late era were more likely to require inotropic support, have protein-losing enteropathy, have failure to thrive, and be further from time of Fontan, although less likely to be on ventilator support. Only ventilator support and earlier year of HT were significant risk factors for death in the multivariate analysis. Post-HT Fontan patient survival significantly improved from the early to late era (p = 0.02), particularly in the early phase, with 1-year survival of 77% in the early era and 89% in the late era. Late era non-Fontan CHD patient 1-year post-HT survival was similar to Fontan patients at 92%. CONCLUSIONS:Survival of Fontan patients after HT has significantly improved in the current era. Currently, expected post-HT survival for Fontan patients is on par with other CHD patients. Fontan patients should not be excluded from consideration for HT solely on a history of Fontan.
PMID: 27863728
ISSN: 1552-6259
CID: 4452592
Low-Dose Donor Dopamine Is Associated With a Decreased Risk of Right Heart Failure in Pediatric Heart Transplant Recipients
Richmond, Marc E; Easterwood, Rachel; Singh, Rakesh K; Gilmore, Lisa; Beddows, Kimberly; Zuckerman, Warren A; McFeely, Eric D; Chen, Jonathan M; Addonizio, Linda J
BACKGROUND:Previous studies in adults have suggested that donor dopamine treatment may improve recipient outcomes in organ transplantation; in this analysis, we aimed to determine if donor dopamine reduces the incidence of postoperative right heart failure (RHF) in pediatric heart transplant recipients. METHODS:Data for recipients aged 18 years or younger transplanted at our institution between January 1, 2000, and June 15, 2011, and their respective donors were obtained. The presence of postoperative RHF was assessed for in all subjects. Donor dopamine dose was stratified into 3 groups: none, low-dose (≤5 μg/kg per minute), and high-dose (>5 μg/kg per minute). Logistic regression was used to assess the relationship between donor dopamine dose and recipient RHF. RESULTS:Of 192 recipients, 34 (18%) experienced postoperative RHF. There was no difference in baseline demographics between recipients with and without RHF. When controlling for pulmonary vascular resistance index, graft ischemic time, and cardiopulmonary bypass time, donor low-dose dopamine was independently associated with a decreased risk of RHF (odds ratio, 0.16; 95% confidence interval, 0.04-0.70; P = 0.02); however high-dose dopamine was neither associated with, nor protective of, RHF (odds ratio, 0.31; 95% confidence interval, 0.06-1.6; P = 0.16). CONCLUSIONS:Despite advances in perioperative care of the recipient, RHF persists as a complication of pediatric heart transplantation. In this study, donor pretreatment with low-dose dopamine is associated with a decreased risk of postoperative RHF in pediatric heart recipients. Further studies into this association may be useful in determining the utility of empiric donor pretreatment with low-dose dopamine.
PMCID:4947572
PMID: 26784116
ISSN: 1534-6080
CID: 4452582
Pediatric Cardiac Intensive Care Society 2014 Consensus Statement: Pharmacotherapies in Cardiac Critical Care Immune Therapy
Singh, Rakesh K; Humlicek, Timothy; Jeewa, Aamir; Fester, Keith
OBJECTIVE:In this Consensus Statement, we review the etiology and pathophysiology of inflammatory processes seen in critically ill children with cardiac disease. Immunomodulatory therapies aimed at improving outcomes in patients with myocarditis, heart failure, and transplantation are extensively reviewed. DATA SOURCES/METHODS:The author team experience and along with an extensive review of the medical literature were used as data sources. DATA SYNTHESIS/RESULTS:The authors synthesized the data in the literature to present current immumodulatory therapies. For each drug, the physiologic rationale, mechanism of action, and pharmacokinetics are synthesized, and the evidence in the literature to support the therapy is discussed. CONCLUSIONS:Immunomodulation has a crucial role in the treatment of certain pediatric cardiac diseases. Immunomodulatory treatments that have been used to treat myocarditis include corticosteroids, IV immunoglobulin, cyclosporine, and azathioprine. Contemporary outcomes of pediatric transplant recipients have improved over the past few decades, partly related to improvements in immunomodulatory therapy to prevent rejection of the donor heart. Immunosuppression therapy is commonly divided into induction, maintenance, and acute rejection therapy. Common induction medications include antithymocyte globulin, muromonab-CD3, and basiliximab. Maintenance therapy includes chronic medications that are used daily to prevent rejection episodes. Examples of maintenance medications are corticosteroids, cyclosporine, tacrolimus, sirolimus, everolimus, azathioprine, and mycophenolate mofetil. Rejection of the donor heart is diagnosed either by clinically or by biopsy and is treated with intensification of immunosuppression.
PMID: 26945331
ISSN: 1529-7535
CID: 4490712
Diagnosis and treatment strategies for children with myocarditis [Review]
Singh, Rakesh K.; Yeh, Justin C.; Price, Jack F.
ISI:000394676700006
ISSN: 1058-9813
CID: 4490702
Proceedings of 2015 Innovations in Pediatric Heart Failure Symposium Preface [Editorial]
Singh, Rakesh K.; Chang, Anthony C.; Towbin, Jeffrey A.; Lipshultz, Steven E.
ISI:000394676700001
ISSN: 1058-9813
CID: 4490692
Prevalence, predictors, and outcomes of cardiorenal syndrome in children with dilated cardiomyopathy: a report from the Pediatric Cardiomyopathy Registry
Kaddourah, Ahmad; Goldstein, Stuart L; Lipshultz, Steven E; Wilkinson, James D; Sleeper, Lynn A; Lu, Minmin; Colan, Steven D; Towbin, Jeffrey A; Aydin, Scott I; Rossano, Joseph; Everitt, Melanie D; Gossett, Jeffrey G; Rusconi, Paolo; Kantor, Paul F; Singh, Rakesh K; Jefferies, John L
BACKGROUND:The association of cardiorenal syndrome (CRS) with mortality in children with dilated cardiomyopathy (DCM) is unknown. METHODS:With a modified Schwartz formula, we estimated glomerular filtration rates (eGFR) for children ≥1 year of age with DCM enrolled in the Pediatric Cardiomyopathy Registry at the time of DCM diagnosis and annually thereafter. CRS was defined as an eGFR of <90 mL/min/1.73 m(2). Children with and without CRS were compared on survival and serum creatinine concentrations (SCr). The association between eGFR and echocardiographic measures was assessed with linear mixed-effects regression models. RESULTS:Of 285 eligible children with DCM diagnosed at ≥1 year of age, 93 were evaluable. CRS was identified in 57 of these 93 children (61.3%). Mean (standard deviation) eGFR was 62.0 (22.6) mL/min/1.73 m(2) for children with CRS and 108.0 (14.0) for those without (P < 0.001); median SCr concentrations were 0.9 and 0.5 mg/dL, respectively (P < 0.001). The mortality hazard ratio of children with CRS versus those with no CRS was 2.4 (95% confidence interval 0.8-7.4). eGFR was positively correlated with measures of left ventricular function and negatively correlated with age. CONCLUSIONS:CRS in children newly diagnosed with DCM may be associated with higher 5-year mortality. Children with DCM, especially those with impaired left ventricular function, should be monitored for renal disease.
PMCID:4626312
PMID: 26210985
ISSN: 1432-198x
CID: 4452492
Preview of the innovations in pedatiric heart failure symposium to be held December 3rd-5th, 2015 at the Loewes Coronado Bay Hotel, San Diego CA
Singh, Rakesh K
ORIGINAL:0014659
ISSN: 1554-7787
CID: 4490822