The Revised International Prognostic Scoring System (IPSS-R) was developed for untreated myelodysplastic syndrome (MDS) patients based on clinical data. We created and validated a new model that incorporates mutational data to improve the predictive capacity of the IPSS-R in treated MDS patients. Clinical and mutational data from treated MDS patients diagnosed between January 2000 and January 2012 were used to develop the new prognostic system. A total of 508 patients were divided into training (n=333) and validation (n=175) cohorts. Independent significant prognostic factors for survival included age, IPSS-R, EZH2, SF3B1 and TP53. Weighted coefficients for each factor were used to build the new linear predictive model, which produced four prognostic groups: low, intermediate-1, intermediate-2 and high with a median overall survival of 37.4, 23.2, 19.9 and 12.2 months, respectively, P<0.001. Significant improvement in the C-index of the new model (0.73) was observed compared with the IPSS-R (0.69). The new model predicted outcome both in a separate validation cohort and in another cohort of patients with paired samples at different time points during their disease course. The addition of mutational data to the IPSS-R makes it dynamic and enhances its predictive ability in treated MDS patients regardless of their initial or subsequent therapies.

The function of the small-M r Ras-like GTPase Rap1 remains largely unknown, but this protein has been demonstrated to regulate cortical actin-based morphologic changes in Dictyostelium and the oxidative burst in mammalian neutrophils. To test whether Rap1 regulates phagocytosis, we biochemically analyzed cell lines that conditionally and modestly overexpressed wild-type [Rap1 WT(ϩ)], constitutively active [Rap1 G12T(ϩ)], and dominant negative [Rap1 S17N(ϩ)] forms of D. discoideum Rap1. The rates of phagocytosis of bacteria and latex beads were significantly higher in Rap1 WT(ϩ) and Rap1 G12T(ϩ) cells and were reduced in Rap1 S17N(ϩ) cells. The addition of inhibitors of protein kinase A, protein kinase G, protein tyrosine kinase, or phosphatidylinositide 3-kinase did not affect phagocytosis rates in wild-type cells. In contrast, the addition of U73122 (a phospholipase C inhibitor), calphostin C (a protein kinase C inhibitor), and BAPTA-AM (an intracellular Ca 2ϩ chelator) reduced phagocytosis rates by 90, 50, and 65%, respectively, suggesting both arms of the phospholipase C signaling pathways played a role in this process. Other protein kinase C-specific inhibitors, such as chelerythrine and bisindolylmaleimide I, did not reduce phagocytosis rates in control cells, suggesting calphostin C was affecting phagocytosis by interfering with a protein containing a diacylglycerol-binding domain. The addition of calphostin C did not reduce phagocytosis rates in Rap1 G12T(ϩ) cells, suggesting that the putative diacylglycerolbinding protein acted upstream in a signaling pathway with Rap1. Surprisingly, macropinocytosis was significantly reduced in Rap1 WT(ϩ) and Rap1 G12T(ϩ) cells compared with control cells. Together our results suggest that Rap1 and Ca 2ϩ may act together to coordinate important early events regulating phagocytosis.

Rho family proteins have been implicated in regulating various cellular processes, including actin cytoskeleton organization, endocytosis, cell cycle, and gene expression. In this study, we analyzed the function of a novel Dictyostelium discoideum Rho family protein (RacC). A cell line was generated that conditionally overexpressed wild-type RacC three- to fourfold relative to endogenous RacC. Light and scanning electron microscopy indicated that the morphology of the RacC-overexpressing cells [RacC WT(+) cells] was significantly altered compared with control cells. In contrast to the cortical F-actin distribution normally observed, RacC WT(+) cells displayed unusual dorsal and peripheral F-actin–rich surface blebs (petalopodia, for flower-like). Furthermore, phagocytosis in the RacC WT(+) cells was induced threefold relative to control Ax2 cells, whereas fluid-phase pinocytosis was reduced threefold, primarily as the result of an inhibition of macropinocytosis. Efflux of fluid-phase markers was also reduced in the RacC WT(+) cells, suggesting that RacC may regulate postinternalization steps along the endolysosomal pathway. Treatment of cells with Wortmannin and LY294002 (phosphatidylinositol 3-kinase inhibitors) prevented the RacC-induced morphological changes but did not affect phagocytosis, suggesting that petalopodia are probably not required for RacC-induced phagocytosis. In contrast, inactivating diacylglycerol-binding motif–containing proteins by treating cells with the drug calphostin C completely inhibited phagocytosis in control and RacC WT(+) cells. These results suggest that RacC plays a role in actin cytoskeleton organization and phagocytosis inDictyostelium.

The ED FNP is a significant quality initiative with sustainable interventions, and was able to demonstrate value by decreasing TTA compared to both historical and DA controls in cancer patients presenting to the ED.

While the bone marrow in most patients with myelodysplastic syndromes (MDS) has normal or increased cellularity (hyper-MDS), approximately 10%-15% of MDS patients will present with a hypocellular bone marrow (hypo-MDS).1 Since the diagnosis of MDS relies mainly on the presence of dyplastic morphology of myeloid precursors and/or the presence of recurrent chromosomal abnormalities, low cellularity aspirates in patients with hypo-MDS may compromise morphologic evaluation and karyotypic analyses, and ultimately contribute to difficulties in distinguishing hypo-MDS from other bone marrow failure syndromes. Further, approximately 50% of MDS patients, including those with hypo-MDS, have normal karyotype by metaphase cytogenetics (MC), which makes the distinction even more difficult. 2We previously reported that single nucleotide polymorphism (SNP) array karyotyping can improve the detection of chromosomal lesions that can distinguish hypo-MDS patients from those with aplastic anemia (AA).3 This finding suggests that clonal abnormalities can be detected in haematologica 2015; 100:e434 LETTERS TO THE EDITOR © F e r r a t a S t o r t i F o u n d a t i o nhypo-MDS and AA by using higher sensitivity methods other than MC. Recently, next generation sequencing (NGS) technologies of the human genome identified several genes that are frequently affected by somatic mutations and play an important role in both the prognosis and the pathogenesis of MDS.4-6 Some of these mutations have a significant impact on disease phenotype, the progression of MDS to acute myeloid leukemia (AML), and on overall survival (OS).4-6 Somatic mutations in genes such as ASXL1, TET2, and DNMT3A are present in healthy individuals, and their incidence increases with age.7 More importantly, the presence of these mutations predisposes these individuals to develop hematologic malignancies.7 Furthermore, somatic mutations in genes such as ASXL1, TET2, DNMT3A and BCOR, were found in 19% of patients with AA, and their presence was associated with an increased risk of transformation to MDS and AML. 8These findings suggest that somatic mutations in certain genes have the potential to contribute to both disease initiation and progression.Using NGS technologies, we hypothesized that identification of somatic mutations and their combinations may help to define the clonal architecture that can lead to the development of hypo-MDS, and that these somatic mutations can possibly be used to aid in establishing the diagnosis.Bone marrow and peripheral blood samples were collected from 237 patients diagnosed with MDS (according to the 2008 WHO criteria) 9 at our institution between January 2000 and December 2013. Informed consent for sample collection was obtained according to protocols approved by the institutional review boards of Cleveland Clinic and in accordance with the Declaration of Helsinki. Hypo-MDS was defined using a standard definition of bone marrow cellularity