The American Society of Hematology (ASH) Medical Educators Institute: a Pilot Faculty Development Project for Hematology Educators.

Clinician educators at academic medical centers often lack the community, mentorship, and faculty development to support their missions around education scholarship and teaching. Inadequate support for clinician educators can lead to professional dissatisfaction and slowed academic advancement. In 2014, ASH conducted a needs assessment of medical school hematology course directors, hematology-oncology fellowship program directors, and other ASH members identified as educators to determine this community's desire for faculty development in medical education. These data furthered the development of an annual faculty development program for hematology educators offering an interactive curriculum and support for an educational scholarly project. The needs assessment indicated that over 70% of respondents would be personally interested in a faculty development opportunity for hematology educators and only 11% had previously participated in such a program. A steering committee designed an intervention blending didactics, interactive small group exercises, webinars, mentorship for a scholarly project, 360-degree feedback for each participant, and a forum to discuss common career development goals. Of 42 applicants, 20 participants were chosen for the inaugural workshop. Following successful execution of the workshop, participants reported significant increase in confidence in the knowledge, skills, and attitudes targeted by the curriculum. A series of follow-up webinars have been developed to deliver additional content not covered during the workshop and to continue mentorship relationships. The curriculum will be further refined based on feedback from faculty and participants. Long-term outcome measurement will include tracking all participants' publications and presentations, time to promotion, and involvement in national medical education initiatives.

Between a rux and a hard place: evaluating salvage treatment and outcomes in myelofibrosis after ruxolitinib discontinuation.

Ruxolitinib is a JAK1/2 inhibitor that is effective in managing symptoms and splenomegaly related to myelofibrosis (MF). Unfortunately, many patients must discontinue ruxolitinib, at which time treatment options are not well defined. In this study, we investigated salvage treatment options and clinical outcomes among MF patients who received and discontinued ruxolitinib outside the context of a clinical trial. Among 145 patients who received ruxolitinib, 23 died while on treatment, 58 remained on treatment at time of analysis, leaving 64 people available for analysis. Development of cytopenias was the most common reason for discontinuation (38%) after median treatment time of 3.8 months (mo). The majority of patients received some form of salvage therapy after ruxolitinib discontinuation (n = 42; 66%), with allogeneic hematopoietic stem cell transplant (alloHSCT) (n = 17), being most commonly employed. Lenalidomide, thalidomide, hydroxyurea, interferon, and danazol were used with similar frequency. The response rate to salvage treatment was 26% (8 responses) and responses were most often seen with lenalidomide or thalidomide. Improved outcomes were observed in patients who underwent alloHSCT or received salvage therapy compared to those who did not receive additional therapy. Median overall survival (OS) after ruxolitinib discontinuation was 13 months. These findings show that salvage therapy can provide clinical responses after ruxolitinib discontinuation; however, these responses are rare and outcomes in this patient population are poor. This represents an area of unmet clinical need in MF.

The Treatment Landscape of Myelofibrosis Before and After Ruxolitinib Approval.

INTRODUCTION/BACKGROUND: Myelofibrosis (MF) is a chronic myeloproliferative neoplasm that presents with a heterogeneous clinical phenotype and prognosis. Before the US Food and Drug Administration approval of ruxolitinib, treatment options were varied and had limited effect. The increased use of ruxolitinib has drastically altered the MF treatment landscape. In this study, we aimed to clarify the clinical situations in which ruxolitinib is being used and analyze its effect on this landscape. PATIENTS AND METHODS: We retrospectively assessed treatment choices for MF patients treated at our institution (n = 309). This population was divided into 2 cohorts on the basis of a diagnosis before (cohort BR: n = 174) or after (cohort AR: n = 135) ruxolitinib approval. Cohorts were further stratified for comparison according to presenting clinical factors. RESULTS: Expectedly, the first-line use of ruxolitinib markedly increased after its approval. AR patients were less likely to receive erythropoiesis-stimulating agents (ESAs; P = .0003) and thalidomide (P = .003) than BR patients. In patients with MF-related symptoms and/or splenomegaly, increased use of ruxolitinib was associated with decreased use of first-line ESA (P = .03) or thalidomide (P = .03). In anemic patients, increased use of first-line ruxolitinib was associated with a decreased use of thalidomide (P = .007). In patients with severe leukocytosis, ruxolitinib use did not significantly increase and hydroxyurea was the preferred first-line agent. CONCLUSION: Overall, the increased use of ruxolitinib appears to have come predominantly at the expense of thalidomide and ESAs, while not having a large effect on the first-line use of hydroxyurea.

Clinical prognostic factors and outcomes of essential thrombocythemia when transformed to myelodysplastic syndromes and acute myeloid leukemia.

Transformation of essential thrombocythemia (ET) to myelodysplastic syndromes or acute myeloid leukemia is infrequent, comprising 1-5% of cases with dismal clinical outcome. Studies on prognosis in ET patients with leukemic transformation are limited. The large cohort included 40 patients (1990-2014) with ET transformation (median age of 59 years, M:F of 1:1). Median time from ET diagnosis to transformation was 76 months (26-481) with median follow-up time of 15 years. Advanced age, myelofibrosis (grade 2-3), and leukocytosis at the time of transformation were associated with inferior OS from transformation (p<0.05). Given rarity of the clinical scenario, multicenter efforts are encouraged.

Identification of a novel inhibitor of JAK2 tyrosine kinase by structure-based virtual screening.

Janus kinase 2 (JAK2) plays a crucial role in the pathomechanism of myeloproliferative disorders and hematologic malignancies. A somatic mutation of JAK2 (Val617Phe) was previously shown to occur in 98% of patients with polycythemia vera and 50% of patients with essential thrombocythemia and primary myelofibrosis. Thus, effective JAK2 kinase inhibitors may be of significant therapeutic importance. Here, we applied a structure-based virtual screen to identify novel JAK2 inhibitors. One JAK2 inhibitor in particular, G6, demonstrated remarkable potency as well as specificity, which makes it as a potential lead candidate against diseases related to elevated JAK2 tyrosine kinase activity.

Gap junction mediated transport of shRNA between human embryonic stem cells.

Gap junction intracellular communication (GJIC) allows the direct transport of small molecules between adjacent cells. We hypothesized that siRNAs in one hESC could inhibit target RNA expression in another hESC via GJIC. We co-cultured green fluorescent protein (GFP)-expressing ENVY hESC with non-GFP-expressing hESC, which had been transduced to stably express shRNA directed against GFP. We discovered that the GFP shRNA expressing hESC inhibited GFP expression in the adjacent GFP-expressing hESC in a dose-dependent manner. This downregulation of GFP expression in ENVY cells was not observed when the co-cultured cells had been transduced with a non-functional GFP shRNA that was mutated at two nucleotides or when the cells were incubated with the GJIC inhibitor, alpha-glycyrrhetinic acid (alpha-GA). We conclude that 21-23 bp double-stranded shRNA/siRNA oligonucleotides are able to move through gap junctions between hESCs and thus can affect gene expression in neighbouring hESC. This novel intercellular gene expression regulatory mechanism may offer new approaches to manipulation of hESC.

TGFbeta regulates the expression and activities of G2 checkpoint kinases in human myeloid leukemia cells.

Transforming Growth Factor-beta (TGFbeta) is known to be a negative regulator of G1 cyclin/cdk activity. It is not clear whether TGFbeta has any effect on G2 checkpoint kinases. We have found that TGFbeta downregulated the expression of several G2 checkpoint kinases including cdc2, cyclin B1, and cdc25c without causing cell accumulation in G2/M phases in two human leukemia cell lines. The inhibition was time-dependent with a maximal inhibition being observed by 24h for cyclin B1 and cdc2 and by 48h for cdc25c. The inhibition was not a result of G1 arrest but a direct effect of TGFbeta which downregulates their expression at mRNA level. In proliferating cells, there was a significant formation of cdc2-pRb complexes, which was decreased to 30% of control levels by 48h after initiating TGFbeta treatment. Cdc2 showed a marked kinase activity on GST-Rb protein in proliferating cells detected by in vitro kinase assay, which was downregulated in response to TGFbeta. In addition, TGFbeta caused a rapid and transient dephosphorylation of cdc2 (Tyr15) and cdc25c (Ser216) for about 2-3h before a dramatic decrease of both molecules by 48h. Taken together, our data suggest that TGFbeta has a direct inhibitory effect on G2 checkpoint kinases, which is regulated at mRNA level. The transient activation of cdc2 and cdc25c and subsequent inhibition of cdc2, cyclin B1, and cdc25c could amplify TGFbeta-induced G1 arrest and growth inhibition.

Ubiquitin/proteasome-dependent degradation of D-type cyclins is linked to tumor necrosis factor-induced cell cycle arrest.

Tumor necrosis factor-alpha (TNF) is well known for its cytotoxic effect on malignant cells. Its role in cell cycle control is relatively less known. In this study, we found that TNF induced G(1) arrest of TF-1 and MV4-11 cells while simultaneously causing apoptosis. Treatment of the cells with TNF for 48 h caused cell cycle arrest, accompanied by dephosphorylation of pRb and reduction in D-type cyclin expression. The down-regulation of the D-type cyclins resulted in approximately 50-80% decrease of the cyclin-dependent kinase activities. Cells treated with calpain-dependent inhibitor ALLN and apoptosis inhibitor zVAD-FMK suppressed degradation of IkappaBalpha and activation of caspase 3, respectively. However, treatment of cells with these two inhibitors was not able to prevent TNF-induced down-regulation of the D-type cyclins. In contrast, proteasome inhibitor MG-132 and lactacystin blocked both TNF-induced degradation of IkappaBalpha and down-regulation of D-type cyclins. These data suggest that down-regulation of D-type cyclins by TNF may be proteasome-proteolysis dependent. Additional support for this conclusion was obtained from experiments showing an increase of proteasome activity in TNF-treated cells and in vitro degradation of cyclin D3 by 26 S proteasome.