Citations

It remains uncertain whether intensive control of blood pressure (BP) results in a lower risk of atrial fibrillation (AF) in patients with hypertension. Using data from SPRINT (Systolic Blood Pressure Intervention Trial), which enrolled participants with hypertension at increased risk of cardiovascular disease, we examined whether intensive BP lowering (target systolic BP [SBP] <120 mm Hg), compared with standard BP lowering (target SBP<140 mm Hg), results in a lower risk of AF. This analysis included 8022 participants (4003 randomized to the intensive arm and 4019 to standard BP arm) who were free of AF at the time of enrollment and with available baseline and follow-up electrocardiographic data. AF was ascertained from standard 12-lead electrocardiograms recorded at biannual study examinations and an exit visit. During up to 5.2 years of follow-up and a total of 28 322 person-years, 206 incident AF cases occurred; 88 in the intensive BP-lowering arm and 118 in the standard BP-lowering arm. Intensive BP lowering was associated with a 26% lower risk of developing new AF (hazard ratio, 0.74 [95% CI, 0.56–0.98]; P =0.037). This effect was consistent among prespecified subgroups of SPRINT participants stratified by age, sex, race, SBP tertiles, prior cardiovascular disease, and prior chronic kidney disease when interactions between treatment effect and these subgroups were assessed using Hommel adjusted P values. In conclusion, intensive treatment to a target of SBP <120 mm Hg in patients with hypertension at high risk of cardiovascular disease has the potential to reduce the risk of AF. Registration— URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01206062.

Abstract Background: The use of postoperative prophylactic antibiotics in pediatric upper urinary tract reconstruction remains controversial. In this study, we elected to examine if prophylactic antibiotics post pediatric dismember pyeloplasty reduce the incidence of clinically symptomatic urinary tract infections (UTIs) in our institution. As a secondary outcome, we also examine which patient population benefits the most from low dose prophylactic antibiotics. Methods: Institutional review board approval (IRB) was obtained. A retrospective study was performed in patients who underwent dismember pyeloplasty (2011-2017) at our institution. Patients with prior history of urologic interventions or other abnormalities of the genitourinary tract were excluded. Demographics (age, gender, ethnicity, insurance status), prior history of culture proven UTIs, surgical details (administration of perioperative antibiotics), and postoperative outcomes, including any readmission 30 days post repair, any urine samples, and culture results were collected. Results: 209 patients (149 boys, 60 girls) met our inclusion criteria. The average age was 6 years (range: 2 months-18 years). 160 patients (77%) underwent robotic-assisted pyeloplasty. Thirty-one patients underwent open repair (15%). 176 (84%) had an indwelling ureteral stent. Eleven patients (5%) had a culture-proven febrile UTI within 30-days postoperatively. No significant differences were seen in postoperative complications or incidence of UTIs when comparing surgical approaches, ureteral stent, or the use of prophylactic post-operative antibiotics. Secondary review of patients with post-operative febrile UTIs noted younger age (2.8 v. 6.2 years, p = 0.02) and positive intraoperative urine culture (p = 0.01) as significant risk factors. Conclusion: The incidence of postoperative UTIs in our cohort is relatively low. There is a higher incidence of febrile UTIs in patients less than 3 years old and those with positive intraoperative urine culture. The use of prophylactic antibiotics in patients post dismember pyeloplasty did not appear to affect the incidence of febrile culture proven UTIs, however, might be important in younger patients pre potty training.

The relationship between selenium and metabolic syndrome (MetS) has been discussed controversially, and limited studies have examined the associations of single nucleotide polymorphisms in selenoproteins genes with MetS. Hence, to examine the associations of plasma selenium concentrations and selenoprotein P rs7579 polymorphism with MetS, a case-control study of 1279 MetS cases and 1279 sex- and age- (±2 years) matched controls was conducted based on the baseline data of the Tongji-Ezhou Cohort study. Plasma selenium concentrations were measured by inductively coupled plasma mass spectrometry. MetS was defined using the definition of the Joint Interim Statement, adjusted for the Chinese population. In addition, the rs7579 polymorphism was genotyped by the Agena MassARRAY System. Plasma selenium concentrations in the MetS group were higher than in the control group (93.88 μg/L (83.17-107.41) vs. 92.66 μg/L (82.36-103.53), P<0.05). Compared with quartile 4 (≥103.53 μg/L), the multivariate-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) associated with MetS were 0.79 (0.59-1.06) for quartile 1 (<82.36 μg/L), 0.75 (0.56-1.01) for quartile 2 (82.37-92.66 μg/L), and 0.61 (0.45-0.83) for quartile 3 (92.67-103.52 μg/L). The cubic spline analyses revealed a U-shaped association between plasma selenium and MetS, with the lowest risk at around 93.69 μg/L. Moreover, in cubic spline analyses, plasma selenium showed U-shaped associations with central obesity and high blood pressure, positive associations with hypertriglyceridemia and hyperglycemia, and a negative association with low high-density lipoprotein cholesterol. Additionally, both the GA and GA+AA genotype carriers were associated with increased ORs of MetS comparing with the GG genotype carriers. Our findings suggested a U-shaped association between plasma selenium and MetS and diverse associations between plasma selenium and components of MetS. Furthermore, our study found that the A allele of rs7579 was associated with higher odds of MetS. Further studies are needed to confirm our findings and elucidate the underlying mechanisms.

Abstract Activation of NFkB has been noted in late B-cell malignancies, but no genetic basis for this activation has been shown except for rare mutations of the NFkB pathway in lymphoma and none have been described in MM. Bortezomib, highly tumoricidal in a subset of MM patients, inhibits NFkB suggesting it’s role as a therapeutic target. Here we show for the first time the critical importance of mutations that dysregulate this potential survival pathway in human myeloma cell lines (HMCL) and new diagnosis MM patients. We performed high-density oligonucleotide array CGH (Agilent 44k) on CD138+ selected MM cells from 68 patients and 42 unique HMCL. Initially we focused on small loci, bi-allelically deleted, as markers for inactivation of potential tumor suppressor genes. We next developed FISH probes for the identified loci to confirm the bi-allelic deletions seen by aCGH. We next sequenced all samples with monoallelic deletions, and additional unselected patients, and identified additional inactivating mutations. Multiple novel tumor suppressor genes (TSG) were identified and validated, whose loss of function (both in patients and HMCL) leads to activation of the non-canonical NFkB pathway including: TRAF2 (9q34), TRAF3 (14q32), BIRC2/BIRC3 (11q22) and CYLD (16q12). Functional studies showed that HMCL with deletion or mutations in these genes have markedly increased NFkB2 p52/p100 ratios relative to other HMCL (and for BIRC2/BIRC3 relative to an isogenic line that retains one copy of BIRC2/BIRC3), indicating genetic activation of the non-canonical NFkB pathway. Reintroduction of deleted TSG into HMCL inhibited cell growth and resulted in cell death (see data on abstract by J. Keats et al). We next focused our analysis (of combined aCGH and GEP data) on positive regulators of this pathway. Rare IgH translocations of NIK have recently been identified in MM. By aCGH we identified amplification and rearrangements of NIK. We identified dysregulated expression of TNF family receptors that activate the non-canonical pathway: CD40 (translocation), TACI (amplification) and LTBR. All of the HMCL with these mutations also showed increased NFkB2 p52/p100 ratios, consistent with activation of the non-canonical NFkB. These mutations correlate with a gene expression profile of NFkB activation that is detected in one half of patients. In summary, we have determined for the first time the genetic basis for constitutive NFkB activation - present in 19/42 HMCL, and we estimate in at least one quarter of newly diagnosed patients (approximately one half of those with evidence of NFkB activation by GEP). We propose a mechanism in which positive (TACI, CD40, LTBR) and negative regulators (TRAF2, TRAF3, BIRC2/BIRC3, CYLD) of the pathway converge on NIK to mediate the processing of NFKB2 p100 to p52. The preponderance of genetic evidence suggests that drugs that target the non-canonical NFkB pathway, will be most effective in treating the 50% of MM patients with NFkB activation.

Abstract We have conducted systematic small interfering RNA (siRNA) lethality screening of the kinome and “druggable genome” in human myeloma cell lines (HMCL) to functionally generate a comprehensive map of critical genes and vulnerabilities in human myeloma tumors. KMS11 human myeloma cells were screened with both an 1800 oligo (639 gene) siRNA library targeting the kinome and with a 13,984 oligo (6,791 gene) library targeting the druggable genome in duplicate using optimized conditions that resulted in &gt;95% transfection efficiency and &lt;5% background cytotoxicity. siRNA were used at low concentration (13nM) to minimise off-target cellular effects. Each gene was initially screened with at least 2 distinct siRNA. Universally lethal and non-silencing siRNA were tested in parallel as controls. Viability was measured at 96 hours by ATP-dependent luminescence and was normalized to the mean and distribution of controls by the B-score method. Approximately 14% of kinome siRNA and 5.8% of druggable genome siRNA caused important reductions in HMCL viability (greater than three standard deviations from control samples treated with non-silencing siRNA), compared with an anticipated rate due to chance of only 0.135%. Short-listed kinome vulnerabilities were validated by repeat targeting in a second lethality screening experiment in KMS11 using a total of four independent siRNA per gene. Forty-two kinases were confirmed as critical for myeloma cell survival. Unsupervised pathway analysis indicates that approximately half are concentrated within established pathways involved in cytokine (VEGFR, FGFR3, IGFR/IL6R) signaling and regulation of cell cycle, apoptosis or metabolism. The role of other survival kinases in myeloma are novel. The selectivity of kinome vulnerabilities identified in KMS11 for myeloma cells versus other tissues was examined by parallel silencing of these targets in KMS11 and JJN3 myeloma cells and in non-myeloma 293 and A549 epithelial cells. The most lethal kinase targets in myeloma that simultaneously show experimental evidence of tumor selectivity include aurora kinase A (AURKA), G-protein receptor coupled kinase 6 (GRK6) and protein kinase N1 (PKN1). By gene expression analyses, PKN1 and GRK6 are both preferentially expressed in plasma cells, compared with an analysis of &gt;50 somatic tissues in which they are absent or only weakly expressed. The extent to which the kinome vulnerabilities identified in KMS11 occur in other HMCL was assessed by tertiary siRNA screening and by lentiviral shRNA techniques. More than 75% of kinases vulnerable in KMS11 cells are recurrently vulnerable in other myeloma tumor lines. Secondary validation studies of all genomic vulnerabilities identified from the much larger siRNA lethality screen of the druggable genome in myeloma cells is ongoing, however, to date 134 genes have been validated as essential myeloma survival factors during primary screening by concordant lethality of 2/2 independent siRNA (compared with an expected rate due to chance of n&lt;1 genes). Significantly, proteosome subunits and specific ubiquitin ligases number amongst the most potently lethal genomic vulnerabilities in KMS11. Overall, this attempt to systematically and functionally document all genetic vulnerabilities in myeloma provides a strong rational impetus for the development of novel therapies that optimally target susceptibilities inherent within myeloma tumors.

Abstract From a high throughput RNAi screen of the human druggable genome targeting the KMS11 cell line, we identified the suppression of the vacuolar H+- ATPase (V-ATPase) family as cytotoxic to myeloma cells. In the screen, two oligos against each gene for the V-ATPase subunits ATP6V1A and ATP6V1B1 resulted in suppression of cell growth (50% and 60% inhibition of cell viability respectively). We further confirmed this result using both lentiviral shRNA knockdown and two small molecule inhibitors specific for V-ATPase. Silencing of ATP6V1A by lentiviral shRNA knock-down in KMS11 and in OPM1 myeloma cell lines caused 75–80% reduction of cell viability at 5 days post infection (measured by MTT assay). Consistent with this result, the V-ATPase specific inhibitors, bafilomycin A1 and REATA 203, both inhibited the growth of a genetically heterogeneous and standardized panel of 14 human myeloma cell lines in vitro with an IC50 ranging from 2.2 – 8.9 nM (mean 5.25 nM) for bafilomycin A1 and 46–1594 nM (mean 542.5 nM)) for REATA 203. We further demonstrated that patient samples (n=10) were sensitive to 20nM bafilomycin A1 which induced a mean of 58% of MM cells to undergo apoptosis (range 10% to 93%) after 24 hours of treatment. Similar to bafilomycin A1, treatment of primary patient-derived MM cells with 500 nM REATA 203 for 72 hours resulted in a mean 69% apoptosis (range 24% to 97%). In contrast, non-myeloma cells (the CD138- fractions of the bone marrow samples) were less sensitive - mean 9% apoptosis (range from 0% to 34%) under the same treatment conditions. Of high interest, however, unlike most drugs we have studied in pre-clinical myeloma models, the cytotoxicity induced by bafilomycin A1 in MM cell lines is abrogated by co-culture with patient bone marrow stromal cells but is not affected by IL-6 or IGF-1 treatment. Dexamethasone- or melphalan-resistant MM cell lines were also highly sensitive to both bafilomycin A1 and REATA 203. In a xenographic JJN3 mouse model, bafilomycin A1 suppresses and delays growth of tumor in a dose-dependent fashion. Gene expression analysis of normal-donor bone marrow plasma cells (n=19), primary tumor samples from MM patients (n=107) and normal somatic tissues demonstrates ubiquitous expression of most subunits of V-ATPase, however, some subunits are preferentially expressed in myeloma cells compared with normal plasma cells, including ATP6V1F (84% vs. 11%), ATP6V1E1 (29% vs. 5%), ATP6V1G2 (17% vs. 0%) and ATP6V0E 2 (36% vs. 16%). In conclusion, our data indicate that vacuolar H+-ATPase inhibitors are of interest as potential therapeutics for MM.

Abstract HACS1 is a SH3 (Src homology 3) and SAM (sterile alpha motif) domain containing adaptor protein that is expressed in activated B and dendritic cells, is up-regulated by Interleukin 4 in the process of B cell activation and likely serves to dampen the immune response. To elucidate the function of HACS1, we generated HACS1 gene knockout mice by deletion of the SH3 and SAM domains. HACS1−/− mice were viable and fertile and had normal bone marrow B cell development and normal splenic T and B cell populations. However, adult HACS1−/− mice had increased numbers of peritoneal B1 cells (IgM+CD5+). Upon LPS plus BCR or TCR stimulations, splenic cells from HACS1−/− mice demonstrated an upregulation of activation markers with increased intensity of CD23 expression or increased population of CD69 positive cells. Purified B220+ splenic B cells from HACS1−/− mice showed increased cell proliferation upon BCR stimulation. Both T helper type 1 (Th1) and T helper type 2 (Th2) humoral responses were enhanced in HACS1−/− mice upon immunization with T cell-dependent antigen NP-KLH, which resulted in increased production of interferon-gamma (IFN-γ), anti-NP IgG2a and IL-4, as well as anti-NP IgG1 and IgE. Upon immunization with T cell-independent antigens such as TNP-LPS and TNP-Ficoll, HACS1−/− mice had increased production of anti-TNP IgM and IgG3 as compared to normal controls. The in vitro maturation of bone marrow-derived dentritic cells from HACS1−/− mice was similar to wild-type mice but HACS1−/− dentritic cells showed increased IL-12 production upon stimulation with anti-CD40 or LPS. There was no significant difference in antigen uptake by cultured dentritic cells from non-immunized wild-type or knockout mice. However, in immunized mice, an increase in antigen uptake in HACS1−/− dentritic cells was observed. We further demonstrate that the HACS1−/− B cells had increased tyrosine phosphorylation in the resting state. As deletion of the SH3 & SAM domains of HACS1 appears to generate a hypersensitive immune response, our results collectively support that HACS1 negatively regulates adaptive immunity.

Abstract Bortezomib and related proteasome inhibitors have profound pre-clinical and clinical activity in Multiple Myeloma (MM). However, the critical molecular target(s) modulated by proteosome inhibition remains unknown. The overall response rate to bortezomib in relapsed and refractory MM patients is consistently 35%–50%, suggesting specific molecular targets or resistance mechanisms are inherent in patients. None of the known effects of bortezomib has been shown to correlate with clinical responses in patients or to explain the unique sensitivity of MM (as opposed to other malignancies) to these reagents. Therefore, in this study, we have conducted a small interfering RNA (siRNA) screen of the druggable genome in human myeloma cells to identify genes that modulate sensitivity to bortezomib. KMS11 human myeloma cells were reverse transfected with 13,984 synthetic short interfering RNAs (siRNA) against each of 6992 druggable targets (2 siRNA/gene with a single-siRNA per well/384 well format). At 24 hours post transfection, bortezomib was added at IC10, 30, 60 and 90. Cell viability was measured by ATP-dependent luminescence assay 72 hours post drug treatment. The resulting data from primary screening was evaluated for multiple quality control metrics and found to exceed all expected performance parameters with &gt;99% global transfection efficiency, &lt;0.25 CV values across the dataset with minimal plate-to-plate and set-to-set variation observed. From analysis of the primary screening data, a core panel of 320 (4.6% of druggable targets in library) bortezomib sensitizers were identified. 187 (58%) of these were further confirmed in a secondary screening experiment by multiple (2 to 4) independent siRNA. Among these 187 genes (2.6% of the genes investigated), some known targets, such as proteasome subunits are evident. Other genes belonging to the same functional gene families (e.g. TNF receptor family, Ras family, kinases, oncogenes and transporter proteins) or functioning within the same network of signal transduction (e.g. NF-kB, Wnt and estrogen receptor pathways) are evident. Our primary screen also identified genes that attenuate bortezomib-induced cytotoxicity. Members in this group include genes implicated in the negative regulation of cell proliferation and survival, such as NF-kB inhibitors, JNK pathway activators, tumor suppressors, apoptosis inducers and phosphatases. These studies enable dissection of the molecular mechanism of bortezomib in myeloma cells and may serve to point to biomarkers for response prediction and novel chemotherapeutic combination therapies.

8506 Background: A randomized study (Int J Rad Oncol Biol Phys 54:195–202, 2002) demonstrated a beneficial effect for octreotide in the treatment of diarrhea in patients receiving pelvic radiation therapy. This North Central Cancer Treatment Group study was undertaken to determine the effectiveness of depot octreotide in the prevention of diarrhea during pelvic radiation therapy. Methods: Patients receiving pelvic radiation therapy, with a planned minimum dose of 45 Gy at 1.70–2.1 Gy per day, were eligible for this study. The study was designed for a Wilcoxon test, with 112 evaluable patients, to have 85% power to detect a further one grade decrease in diarrhea over and above that experienced by patients treated with placebo. Between June 13, 2002 and October 28, 2005, 120 evaluable patients were randomly allocated, in double blind fashion, to receive octreotide (62 patients) or placebo (58 patients), prior to the fourth radiation therapy fraction. Octreotide dosing: Octreotide, 100 micrograms subcutaneously on day 1 followed by depot octreotide, 20 milligrams intramuscularly on days 2 and 29. Results: Grade 0, 1, 2 and 3 diarrhea was observed in 17%, 32%, 26% and 26% of patients treated with octreotide and 18%, 34%, 22%, and 26% of patients treated with placebo (P=0.86). Grade 0, 1, 2 and 3 tenesmus was observed in 55%, 30%, 11% and 4% of patients treated with octreotide and 76%, 16%, 4%, and 4% of patients treated with placebo (P=0.04). No other statistically significant differences in toxicity were observed. Conclusions: Octreotide, as administered in this study, did not decrease diarrhea during pelvic radiation therapy. [Table: see text]

AbstractProper cell‐cycle progression is essential for the self‐renewal and differentiation of human pluripotent stem cells (hPSCs). The fluorescent ubiquitination‐based cell‐cycle indicator (FUCCI) has allowed the dual‐color visualization of the G1 and S/G2/M phases in various dynamic models, but its application in hPSCs is not widely reported. In addition, lineage‐specific FUCCI reporters have not yet been developed to analyze complex tissue‐specific cell‐cycle progression during hPSC differentiation. Desiring a robust tool for spatiotemporal reporting of cell‐cycle events in hPSCs, we employed the CRISPR/Cas9 genome editing tool and successfully knocked the FUCCI reporter into the AAVS1 safe harbor locus of hPSCs for stable and constitutive FUCCI expression, exhibiting reliable cell‐cycle‐dependent fluorescence in both hPSCs and their differentiated progeny. We also established a cardiac‐specific TNNT2‐FUCCI reporter for lineage‐specific cell‐cycle monitoring of cardiomyocyte differentiation from hPSCs. This powerful and modular FUCCI system should provide numerous opportunities for studying human cell‐cycle activity, and enable the identification and investigation of novel regulators for adult tissue regeneration.