Perfusion of porous scaffolds transports cells to the surface to yield cellular constructs for 3D models of disease and for tissue engineering applications. While ceramic scaffolds mimic the structure and composition of trabecular bone, their opacity and tortuous pores limit the penetration of light into the interior. Scaffolds that are both perfusable and amenable to fluorescence microscopy are therefore needed to visualize the spatiotemporal dynamics of cells in the bone microenvironment.
View Article and Find Full Text PDFUnlabelled: When breast cancer metastasizes to bone, treatment options are limited. Failure to treat bone metastases is thought to be due to therapy-resistant features of the bone marrow microenvironment. Using a murine model of bone metastatic mammary carcinoma, we demonstrate that systemic delivery of polymer nanoparticles loaded with cyclic dinucleotide (CDN) agonists of stimulator of interferon genes (STING) inhibited tumor growth and bone destruction after 7 days of treatment.
View Article and Find Full Text PDFTreatment for myelodysplastic syndromes (MDS) remains insufficient due to clonal heterogeneity and lack of effective clinical therapies. Dysregulation of apoptosis is observed across MDS subtypes regardless of mutations and represents an attractive therapeutic opportunity. Venetoclax (VEN), a selective inhibitor of anti-apoptotic protein B-cell lymphoma- 2 (BCL2), has yielded impressive responses in older patients with acute myeloid leukemia (AML) and high risk MDS.
View Article and Find Full Text PDFBackground: All-trans retinoic acid (ATRA), a derivate of vitamin A, has been successfully used as a therapy to induce differentiation in M3 acute promyelocytic leukemia (APML), and has led to marked improvement in outcomes. Previously, attempts to use ATRA in non-APML in the clinic, however, have been underwhelming, likely due to persistent signaling through other oncogenic drivers. Dysregulated JAK/STAT signaling is known to drive several hematologic malignancies, and targeting JAK1 and JAK2 with the JAK1/JAK2 inhibitor ruxolitinib has led to improvement in survival in primary myelofibrosis and alleviation of vasomotor symptoms and splenomegaly in polycythemia vera and myelofibrosis.
View Article and Find Full Text PDFChronic myelomonocytic leukemia (CMML) is a myelodysplastic syndrome/myeloproliferative neoplasm overlap syndrome characterized by monocytic proliferation in the presence of dysplastic bone marrow changes, inflammatory symptoms, and propensity for transformation to acute myeloid leukemia (AML), with a poor prognosis and limited treatment options. Unlike the α and β isoforms, the phosphatidylinositol-3-kinase (PI3K)-δ signaling protein is predominantly expressed by hematopoietic cells and therefore has garnered interest as a potential target for the treatment of lymphomas and leukemias. We revealed a pattern of increased PIK3CD:PIK3CA ratio in monocytic M5 AML patients and cell lines, and this ratio correlated with responsiveness to pharmacological PI3K-δ inhibition in vitro.
View Article and Find Full Text PDFIntroduction: The updated common rule, for human subjects research, requires that consents "begin with a 'concise and focused' presentation of the key information that will most likely help someone make a decision about whether to participate in a study" (Menikoff, Kaneshiro, Pritchard. . 2017; (7): 613-615.
View Article and Find Full Text PDFPurpose: The BCL2 inhibitor, venetoclax, has transformed clinical care in acute myeloid leukemia (AML). However, subsets of patients do not respond or eventually acquire resistance. Venetoclax-based regimens can lead to considerable marrow suppression in some patients.
View Article and Find Full Text PDFThe COVID-19 pandemic has presented unprecedented challenges and opportunities for medical schools in the United States. In this Invited Commentary, the authors describe a unique collaboration between the University of Massachusetts Medical School (UMMS), the only public medical school in the state; the University of Massachusetts Memorial Medical Center (UMMMC); and the Commonwealth of Massachusetts. Through this partnership, UMMS was able to graduate fourth-year medical students 2 months early and deploy them to UMMMC to care for patients and alleviate workforce shortages during the COVID-19 surge, which peaked in Massachusetts in April 2020.
View Article and Find Full Text PDFIntroduction: Leadership is an area of education and training that is critical to the development of medical providers as health care professionals, yet few medical school curricula offer formal training in this area.
Methods: We designed and implemented a course to develop and enhance the leadership and teamwork skills of first-year medical students to better prepare them for medical practice. Following a systematic literature review to identify leadership core competencies, the Leadership in Medicine Optional Enrichment Elective (OEE) was developed in accordance with the University of Massachusetts Medical School's course guidelines.
The selective inhibitor of nuclear export (SINE) compounds selinexor (KPT-330) and eltanexor (KPT-8602) are from a novel class of small molecules that target exportin-1 (XPO1 [CRM1]), an essential nucleo-cytoplasmic transport protein responsible for the nuclear export of major tumor suppressor proteins and growth regulators such as p53, p21, and p27. XPO1 also affects the translation of messenger RNAs for critical oncogenes, including MYC, BCL2, MCL1, and BCL6, by blocking the export of the translation initiation factor eIF4E. Early trials with venetoclax (ABT-199), a potent, selective inhibitor of BCL2, have revealed responses across a variety of hematologic malignancies.
View Article and Find Full Text PDFObjective: The purpose of this study was to present the design, model, and data analysis of an interrupted time series (ITS) model applied to evaluate the impact of health policy, systems, or environmental interventions using count outcomes. Simulation methods were used to conduct power and sample size calculations for these studies.
Methods: We proposed the models and analyses of ITS designs for count outcomes using the Strengthening Translational Research in Diverse Enrollment (STRIDE) study as an example.
Objective: To discuss the study design and data analysis for three-phase interrupted time series (ITS) studies to evaluate the impact of health policy, systems, or environmental interventions. Simulation methods are used to conduct power and sample size calculation for these studies.
Methods: We consider the design and analysis of three-phase ITS studies using a study funded by National Institutes of Health as an exemplar.
Inhibitors of the bromodomain and extraterminal domain family (BETi) offer a new approach to treat hematological malignancies, with leukemias containing mixed lineage leukemia rearrangements being especially sensitive due to a reliance on the regulation of transcription elongation. We explored the mechanism of action of BETi in cells expressing the t(8;21), and show that these compounds reduced the size of acute myeloid leukemia cells, triggered a rapid but reversible G /G arrest, and with time, cause cell death. Meta-analysis of PRO-seq data identified ribosomal genes, which are regulated by MYC, were downregulated within 3 hours of addition of the BETi.
View Article and Find Full Text PDFSuppression of apoptosis by expression of antiapoptotic BCL2 family members is a hallmark of acute myeloblastic leukemia (AML). Induced myeloid leukemia cell differentiation protein (MCL1), an antiapoptotic BCL2 family member, is commonly upregulated in AML cells and is often a primary mode of resistance to treatment with the BCL2 inhibitor venetoclax. Here, we describe VU661013, a novel, potent, selective MCL1 inhibitor that destabilizes BIM/MCL1 association, leads to apoptosis in AML, and is active in venetoclax-resistant cells and patient-derived xenografts.
View Article and Find Full Text PDFMTG16 is a member of the myeloid translocation gene (MTG) family of transcriptional corepressors. While MTGs were originally identified in chromosomal translocations in acute myeloid leukemia, recent studies have uncovered a role in intestinal biology. For example, Mtg16-/- mice have increased intestinal proliferation and are more sensitive to intestinal injury in colitis models.
View Article and Find Full Text PDFUnlabelled: Myeloid cell leukemia 1 (Mcl-1) is an antiapoptotic member of the Bcl-2 family of proteins that when overexpressed is associated with high tumor grade, poor survival, and resistance to chemotherapy. Mcl-1 is amplified in many human cancers, and knockdown of Mcl-1 using RNAi can lead to apoptosis. Thus, Mcl-1 is a promising cancer target.
View Article and Find Full Text PDFBromodomain and extra-terminal domain (BET) family inhibitors offer an approach to treating hematological malignancies. We used precision nuclear run-on transcription sequencing (PRO-seq) to create high-resolution maps of active RNA polymerases across the genome in t(8;21) acute myeloid leukemia (AML), as these polymerases are exceptionally sensitive to BET inhibitors. PRO-seq identified over 1,400 genes showing impaired release of promoter-proximal paused RNA polymerases, including the stem cell factor receptor tyrosine kinase KIT that is mutated in t(8;21) AML.
View Article and Find Full Text PDFThe discovery of JAK2 (V617F) a decade ago led to optimism for a rapidly developing treatment revolution in Ph(-) myeloproliferative neoplasms. Unlike BCR-ABL, however, JAK2 was found to have a more heterogeneous role in carcinogenesis. Therefore, for years, development of new therapies was slow, despite standard treatment options that did not address the overwhelming symptom burden in patients with primary myelofibrosis (MF), post-essential thrombocythemia MF, post-polycythemia vera MF, and myelodysplastic syndrome (MDS)/myeloproliferative neoplasm (MPN) syndromes.
View Article and Find Full Text PDFHistone deacetylase 3 (HDAC3) contributes to the regulation of gene expression, chromatin structure, and genomic stability. Because HDAC3 associates with oncoproteins that drive leukemia and lymphoma, we engineered a conditional deletion allele in mice to explore the physiological roles of Hdac3 in hematopoiesis. We used the Vav-Cre transgenic allele to trigger recombination, which yielded a dramatic loss of lymphoid cells, hypocellular bone marrow, and mild anemia.
View Article and Find Full Text PDFBackground: The Institute of Medicine has called for physician education as a key step in medical error prevention. In our 2002 national survey, pediatric resident education about medical error prevention was sporadic. We sought to describe the amount and type of pediatric resident training about medical errors and to assess the change in training since 2002.
View Article and Find Full Text PDFThe t(8;21) and t(16;21) that are associated with acute myeloid leukaemia disrupt two closely related genes termed Myeloid Translocation Genes 8 (MTG8) and 16 (MTG16), respectively. Many of the transcription factors that recruit Mtg16 regulate haematopoietic stem and progenitor cell functions and are required to maintain stem cell self-renewal potential. Accordingly, we found that Mtg16-null bone marrow (BM) failed in BM transplant assays.
View Article and Find Full Text PDFPurpose: Growing data support interprofessional teams as an important part of medical education. This study describes attitudes, barriers, and practices regarding interprofessional education (IPE) in internal medicine (IM) clerkships in the United States and Canada.
Method: In 2009, a section on IPE was included on the Clerkship Directors in Internal Medicine annual survey.