Frequent somatic TET2 mutations in chronic NK-LGL leukemia with distinct patterns of cytopenias.

Chronic natural killer large granular lymphocyte (NK-LGL) leukemia, also referred to as chronic lymphoproliferative disorder of NK cells, is a rare disorder defined by prolonged expansion of clonal NK cells. Similar prevalence of STAT3 mutations in chronic T-LGL and NK-LGL leukemia is suggestive of common pathogenesis. We undertook whole-genome sequencing to identify mutations unique to NK-LGL leukemia. The results were analyzed to develop a resequencing panel that was applied to 58 patients. Phosphatidylinositol 3-kinase pathway gene mutations (PIK3CD/PIK3AP1) and TNFAIP3 mutations were seen in 5% and 10% of patients, respectively. TET2 was exceptional in that mutations were present in 16 (28%) of 58 patient samples, with evidence that TET2 mutations can be dominant and exclusive to the NK compartment. Reduced-representation bisulfite sequencing revealed that methylation patterns were significantly altered in TET2 mutant samples. The promoter of TET2 and that of PTPRD, a negative regulator of STAT3, were found to be methylated in additional cohort samples, largely confined to the TET2 mutant group. Mutations in STAT3 were observed in 19 (33%) of 58 patient samples, 7 of which had concurrent TET2 mutations. Thrombocytopenia and resistance to immunosuppressive agents were uniquely observed in those patients with only TET2 mutation (Games-Howell post hoc test, P = .0074; Fisher's exact test, P = .00466). Patients with STAT3 mutation, inclusive of those with TET2 comutation, had lower hematocrit, hemoglobin, and absolute neutrophil count compared with STAT3 wild-type patients (Welch's t test, P ≤ .015). We present the discovery of TET2 mutations in chronic NK-LGL leukemia and evidence that it identifies a unique molecular subtype.

Ubiquitin- and ATP-dependent unfoldase activity of P97/VCP•NPLOC4•UFD1L is enhanced by a mutation that causes multisystem proteinopathy.

p97 is a "segregase" that plays a key role in numerous ubiquitin (Ub)-dependent pathways such as ER-associated degradation. It has been hypothesized that p97 extracts proteins from membranes or macromolecular complexes to enable their proteasomal degradation; however, the complex nature of p97 substrates has made it difficult to directly observe the fundamental basis for this activity. To address this issue, we developed a soluble p97 substrate-Ub-GFP modified with K48-linked ubiquitin chains-for in vitro p97 activity assays. We demonstrate that WT p97 can unfold proteins and that this activity is dependent on the p97 adaptor NPLOC4-UFD1L, ATP hydrolysis, and substrate ubiquitination, with branched chains providing maximal stimulation. Furthermore, we show that a p97 mutant that causes inclusion body myopathy, Paget's disease of bone, and frontotemporal dementia in humans unfolds substrate faster, suggesting that excess activity may underlie pathogenesis. This work overcomes a significant barrier in the study of p97 and will allow the future dissection of p97 mechanism at a level of detail previously unattainable.

Vitamin D pathway activation selectively deactivates signal transducer and activator of transcription (STAT) proteins and inflammatory cytokine production in natural killer leukemic large granular lymphocytes.

Calcitriol, the active form of vitamin D, has been well documented to act directly on immune cells and malignant cells. Activated T cells are one of the best characterized targets of calcitriol, with effects including decreasing inflammatory cytokine output and promoting anti-inflammatory cytokine production. However, the effects of calcitriol on natural killer (NK) cells are less clear. Reports suggest that only immature NK cell populations are affected by calcitriol treatment resulting in impaired cytotoxic function and cytokine production, while mature NK cells may have little or no response. NK cell large granular lymphocyte leukemia (NK-LGLL) is a rare leukemia with CD3-CD16+CD56+NK cell clonal expansion. The current standard treatments are immunosuppressant therapies, which are not curative. The Janus kinase (JAK) - signal transducer and activator of transcription (STAT) pathway is hyperactivated in LGLL and is one pathway of interest in new drug target investigations. We previously demonstrated the ability of calcitriol to decrease STAT1 tyrosine 701 (p-STAT1) and STAT3 tyrosine 705 (p-STAT3) phosphorylation as well as inflammatory cytokine output of T cell large granular lymphocyte leukemia cells, but did not determine the effects of calcitriol on NK-LGLL. Therefore, in the present study, we investigated whether NKL cells, a model of NK-LGLL, and NK-LGLL patient peripheral blood mononuclear cells (PBMCs) are susceptible to treatment with calcitriol or seocalcitol (EB1089), a potent analog of calcitriol. NKL cells are dependent on interleukin (IL)-2 for survival and we show here for the first time that treatment with IL-2 induced tyrosine phosphorylation of STATs 1 through 6. Both calcitriol and EB1089 caused significant upregulation of the vitamin D receptor (VDR). IL-2 induction of p-STAT1 and p-STAT3 phosphorylation was significantly decreased after calcitriol or EB1089 treatment. Additionally, IL-10, interferon (IFN)-γ, and FMS-like tyrosine kinase 3 ligand (Flt-3L) extracellular output was significantly decreased at 100 nM EB1089 and intracellular IL-10 was decreased with either calcitriol or EB1089 treatment. We treated NK-LGLL patient PBMCs with calcitriol or EB1089 and found decreased p-STAT1 and p-STAT3 while VDR increased, which matched the NKL cell line data. We then measured 75 serum cytokines in NK-LGLL patients (n = 8) vs. age- and sex-matched normal healthy donors (n = 8), which is the first serum cytokine study for this LGLL subtype. We identified 15 cytokines, including IL-10 and Flt-3L, which were significantly different between normal donors and NK-LGLL patients. Overall, our results suggest that activating the vitamin D pathway could be a mechanism to decrease STAT1 and 3 activation and inflammatory cytokine output in NK-LGLL patients.

Catabolic Defect of Branched-Chain Amino Acids Promotes Heart Failure.

BACKGROUND: Although metabolic reprogramming is critical in the pathogenesis of heart failure, studies to date have focused principally on fatty acid and glucose metabolism. Contribution of amino acid metabolic regulation in the disease remains understudied. METHODS AND RESULTS: Transcriptomic and metabolomic analyses were performed in mouse failing heart induced by pressure overload. Suppression of branched-chain amino acid (BCAA) catabolic gene expression along with concomitant tissue accumulation of branched-chain α-keto acids was identified as a significant signature of metabolic reprogramming in mouse failing hearts and validated to be shared in human cardiomyopathy hearts. Molecular and genetic evidence identified the transcription factor Krüppel-like factor 15 as a key upstream regulator of the BCAA catabolic regulation in the heart. Studies using a genetic mouse model revealed that BCAA catabolic defect promoted heart failure associated with induced oxidative stress and metabolic disturbance in response to mechanical overload. Mechanistically, elevated branched-chain α-keto acids directly suppressed respiration and induced superoxide production in isolated mitochondria. Finally, pharmacological enhancement of branched-chain α-keto acid dehydrogenase activity significantly blunted cardiac dysfunction after pressure overload. CONCLUSIONS: BCAA catabolic defect is a metabolic hallmark of failing heart resulting from Krüppel-like factor 15-mediated transcriptional reprogramming. BCAA catabolic defect imposes a previously unappreciated significant contribution to heart failure.

Vitamin D in hematological disorders and malignancies.

Commonly known for its critical role in calcium homeostasis and bone mineralization, more recently vitamin D has been implicated in hematological cancer pathogenesis and shows promise as an anti-cancer therapy. Serum levels of 25(OH)D3 , the precursor to the active form of vitamin D, calcitriol, are frequently lower in patients with hematological disease compared to healthy individuals. This often correlates with worse disease outcome. Furthermore, diseased cells typically highly express the vitamin D receptor, which is required for many of the anti-cancer effects observed in multiple in vivo and in vitro cancer models. In abnormal hematological cells, vitamin D supplementation promotes apoptosis, induces differentiation, inhibits proliferation, sensitizes tumor cells to other anti-cancer therapies, and reduces the production of pro-inflammatory cytokines. Although the dosage of vitamin D required to achieve these effects may induce hypercalcemia in humans, analogs and combinatorial treatments have been developed to circumvent this side effect. Vitamin D and its analogs are well tolerated in clinical trials, and thus, further investigation into the use of these agents in the clinic is warranted. Here, we review the current literature in this field.

Impact of COVID-19 on American Family Physicians' Intent to Retreat from Clinical Care.

PURPOSE: This survey evaluated whether the COVID-19 pandemic was a traumatic stress event for family physicians associated with burnout, changes in life priorities, and intentions to retreat from clinical practice. METHODS: We report on 683 clinically active family physicians surveyed through the Council of Academic Family Medicine's Educational Research Alliance (CERA) in the fall of 2021. RESULTS: Overall, 35.2% of family physicians experienced the pandemic as a traumatic stress like event. This was associated with changing life priorities (OR 2.6, CI 1.8-3.9), burnout (OR 1.6, CI 1.1 to 2.4), and withdrawal from clinical practice in various ways. Those who changed their priorities in life were more likely to restrict scope of practice (OR 3.9, CI 2.6-5.9), reduce clinical work effort (OR 3.4, 2.3 to 5.1), relocate (OR 3.1, CI 2.0 to 4.8), retire (OR 2.7, CI 1.4-4.9), reroute their career away from patient care (OR 2.1, CI 1.4-3.1) and less likely to avoid redesigning the practice to improve well-being (OR 0.3, CI 0.2-0.7). Those who experienced burnout were more likely to retire (OR 5.5, CI 2.8 to 10.5), reduce clinical work effort (OR 4.2, CI 2.9-6.1), reroute their career away from patient care (OR 3.9, CI 2.6-5.8), relocate (OR 3.8, CI 2.4 to 5.9), and restrict scope of practice (OR 3.3, CI 2.3 to 4.9). Overall, 48.5% of family physicians expressed some intention to retreat from clinical practice. CONCLUSION: The COVID-19 pandemic impacted family physician's career plans. Remedying burnout is a high-yield opportunity for retaining clinically active family physicians. Physicians retreating from clinical medicine related to changing life's priorities needs further exploration.

Hypertension Severity and Declines in Left Ventricular Ejection Fraction Among Women Receiving Adjuvant Chemotherapy for Breast Cancer (WF-97415 UPBEAT).

BACKGROUND: Hypertension is a risk factor for experiencing left ventricular ejection fraction (LVEF) declines during receipt of potentially cardiotoxic breast cancer (BC) treatment. We sought to determine whether the hypertension stage is associated with LVEF decline during BC treatment. METHODS: Across 24 centers, cardiac magnetic resonance measures of LVEF and brachial arterial blood pressure (BP) measurements were performed in women with stages I to III BC before and 3 months after initiating potentially cardiotoxic chemotherapy. Using multivariable analysis, we assessed in a blinded fashion the association between 3-month ΔLVEF and precancer treatment American Heart Association/American College of Cardiology stages of hypertension. RESULTS: Among 204 women, age averaged 56±1 years with 75% being White and 20% of Black race. Participants received anthracycline (45.6%), trastuzumab (22.5%), cyclophosphamide (52.9%), or paclitaxel (50%). After accounting for pretreatment LVEF, diabetes status, tobacco use, age, the number of antihypertensive medications, and body mass index, those with stage II hypertension experienced an LVEF decline of -2.89% ([95% CI, -0.69% to -5.19%]; P=0.01) relative to individuals with normal BP. Other stages saw nonsignificant declines relative to normal BP to elevated BP (-1.63% [95% CI, -0.62% to 3.88%]; P=0.16) and stage I hypertension (-0.94% [95% CI, -0.90% to 2.78%]; P=0.32). CONCLUSIONS: Compared with women receiving treatment for BC with normal BP, there is a stronger association of decline in LVEF in women with stage II hypertension relative to women with other hypertension stages. This raises the possibility that stage along with hypertension presence may be associated with an increased risk for the LVEF decline among women receiving potentially cardiotoxic chemotherapy for BC. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02791581 and NCT01719562.

The relationship between body composition and left ventricular performance in women with breast, lymphoma, or sarcoma cancer.

BACKGROUND: To understand how body composition in those with elevated body mass index impacts left ventricular function decline during cancer treatment, we determined the association between baseline body mass index (BMI), intra-abdominal adipose tissue (IAT) and subcutaneous adipose tissue (SAT) with baseline to 3-month left ventricular ejection fraction (LVEF) change among women receiving potentially cardiotoxic chemotherapy for breast cancer, lymphoma, or sarcoma. METHODS: Women underwent potentially cardiotoxic chemotherapy, such as doxorubicin, cyclophosphamide, paclitaxel, and trastuzumab, for treatment of breast cancer, lymphoma, or sarcoma. We obtained magnetic resonance images (MRIs) of body composition and cardiac function prior to treatment, and then a repeat MRI for cardiac function assessment at three months into treatment. Analyses and assessment of abdominal adipose tissue volumes and LVEF outcomes were conducted by independent reviewers blinded to all patient identifiers. A general linear model was created to examine associations between adipose tissue depots, BMI, and 3-month LVEF change. RESULTS: Women (n = 210) aged 56 ± 11 years with breast cancer, lymphoma, and sarcoma were enrolled (n = 195, 14, 1 respectively). Baseline BMI, IAT, and SAT fat were independently associated with 3-month LVEF declines (p = 0.001 to 0.025 for all). After adjusting for baseline cardiovascular disease risk factors, BMI, IAT, and SAT, BMI remained the only variable associated with 3-month LVEF decline (p = 0.047). CONCLUSIONS: These results suggest that factors other than abdominal adipose tissue or traditional cardiovascular risk factors may contribute to 3-month declines in LVEF among women with elevated BMI receiving potentially cardiotoxic chemotherapy. Further investigation should be conducted on psychosocial stress, physical activity, sleep, or diet. TRIAL REGISTRATION: DETECTIV_NCT01719562, WF99112, & WF97415-NCT02791581.

Regulation of adipose branched-chain amino acid catabolism enzyme expression and cross-adipose amino acid flux in human obesity.

Elevated blood branched-chain amino acids (BCAA) are often associated with insulin resistance and type 2 diabetes, which might result from a reduced cellular utilization and/or incomplete BCAA oxidation. White adipose tissue (WAT) has become appreciated as a potential player in whole body BCAA metabolism. We tested if expression of the mitochondrial BCAA oxidation checkpoint, branched-chain α-ketoacid dehydrogenase (BCKD) complex, is reduced in obese WAT and regulated by metabolic signals. WAT BCKD protein (E1α subunit) was significantly reduced by 35-50% in various obesity models (fa/fa rats, db/db mice, diet-induced obese mice), and BCKD component transcripts significantly lower in subcutaneous (SC) adipocytes from obese vs. lean Pima Indians. Treatment of 3T3-L1 adipocytes or mice with peroxisome proliferator-activated receptor-γ agonists increased WAT BCAA catabolism enzyme mRNAs, whereas the nonmetabolizable glucose analog 2-deoxy-d-glucose had the opposite effect. The results support the hypothesis that suboptimal insulin action and/or perturbed metabolic signals in WAT, as would be seen with insulin resistance/type 2 diabetes, could impair WAT BCAA utilization. However, cross-tissue flux studies comparing lean vs. insulin-sensitive or insulin-resistant obese subjects revealed an unexpected negligible uptake of BCAA from human abdominal SC WAT. This suggests that SC WAT may not be an important contributor to blood BCAA phenotypes associated with insulin resistance in the overnight-fasted state. mRNA abundances for BCAA catabolic enzymes were markedly reduced in omental (but not SC) WAT of obese persons with metabolic syndrome compared with weight-matched healthy obese subjects, raising the possibility that visceral WAT contributes to the BCAA metabolic phenotype of metabolically compromised individuals.

Adipose transplant for inborn errors of branched chain amino acid metabolism in mice.

Liver transplantation appears to be quite beneficial for treatment of maple syrup urine disease (MSUD, an inherited disorder of branched chain amino acid metabolism); however, there is a limited availability of donor livers worldwide and the first year costs of liver transplants are quite high. Recent studies have suggested that intact adipose tissue, already widely used in reconstructive surgery, may have an underappreciated high capacity for branched chain amino acid (BCAA) metabolism. Here we examined the potential for adipose tissue transplant to lower circulating BCAAs in two models of defective BCAA metabolism, BCATm and PP2Cm [branched chain keto acid dehydrogenase complex (BCKDC) phosphatase] knockout (KO) mice. After 1-2g fat transplant, BCATm and PP2Cm KO mice gained or maintained body weight 3weeks after surgery and consumed similar or more food/BCAAs the week before phlebotomy. Transplant of fat into the abdominal cavity led to a sterile inflammatory response and nonviable transplanted tissue. However when 1-2g of fat was transplanted subcutaneously into the back, either as small (0.1-0.3g) or finely minced pieces introduced with an 18-ga. needle, plasma BCAAs decreased compared to Sham operated mice. In two studies on BCATm KO mice and one study on PP2Cm KO mice, fat transplant led to 52-81% reductions in plasma BCAAs compared to baseline plasma BCAA concentrations of untreated WT type siblings. In PP2Cm KO mice, individual BCAAs in plasma were also significantly reduced by fat transplant, as were the alloisoleucine/Phe ratios. Therefore, subcutaneous fat transplantation may have merit as an adjunct to dietary treatment of MSUD. Additional studies are needed to further refine this approach.

Quantification of branched-chain keto acids in tissue by ultra fast liquid chromatography-mass spectrometry.

Branched-chain keto acids (BCKAs) are associated with increased susceptibility to several degenerative diseases. However, BCKA concentrations in tissues or the amounts of tissue available are frequently at the limit of detection for standard plasma methods. To accurately and quickly determine tissue BCKAs, we have developed a sensitive ultra fast liquid chromatography-mass spectrometry (UFLC-MS) method. BCKAs from deproteinized tissue extractions were o-phenylenediamine (OPD) derivatized, ethyl acetate extracted, lyophilized in a vacuum centrifuge, and reconstituted in 200 mM ammonium acetate. Samples were injected onto a Shimadzu UFLC system coupled to an AB-Sciex 5600 Triple TOF mass spectrometer instrument that detected masses of the OPD BCKA products using a multiple reaction monitoring method. An OPD-derivatized (13)C-labeled keto acid was used as an internal standard. Application of the method for C57BL/6J (wild-type) and PP2Cm knockout mouse tissues, including kidney, adipose tissue, liver, gastrocnemius, and hypothalamus, is shown. The lowest tissue concentration measured by this method was 20 nM, with the standard curve covering a wide range (7.8-32,000 nM). Liquid chromatography-mass spectrometry run times for this assay were less than 5 min, facilitating high throughput, and the OPD derivatives were found to be stable over several days.

Burnout and Disengagement in Pathology: A Prepandemic Survey of Pathologists and Laboratory Professionals.

CONTEXT.­: Despite widely prevalent burnout and attendant disengagement in medicine, the specific patterns and drivers within pathology and laboratory medicine are uncommonly studied. OBJECTIVE.­: To assess the prevalence and drivers of burnout among pathology and laboratory medicine professionals, retrospectively, prior to the COVID-19 pandemic. DESIGN.­: This was a cross-sectional, mixed-methods study engaging pathology and laboratory medicine professionals as subjects. RESULTS.­: Of 2363 respondents, 438 identified as pathologists, 111 as pathology assistants, and 911 as pathology and laboratory professionals. The burnout rate was 58.4% (1380 of 2363) across all respondents in pathology and laboratory medicine. Burnout varied by job role (P < .01) and was highest among pathology and laboratory professionals. Disparities in burnout rate were observed by race. Fifty-six percent (1323 of 2363) of respondents felt that they had at least 1 symptom of burnout and were advancing toward a breaking point. Underlying factors ranked highly among all groups included control over workload and loss of meaning in work. CONCLUSIONS.­: Data provided from this cohort may help departments create successful strategies to reduce disengagement and burnout in the laboratory, especially during periods of increased stress as experienced during the COVID-19 pandemic. Further, these data may serve as a baseline comparison for future studies.

COVID-19 Traumatic Disaster Appraisal and Stress Symptoms Among Health Care Workers: Insights From the Yale Stress Self-assessment.

OBJECTIVE: To determine to what extent did health care workers experience the pandemic as a severe stress event. METHODS: This cross-sectional evaluation of 8299 health care workers, representing a 22% response rate, utilized machine learning to predict high levels of escalating stress based on demographics and known predictors for adverse psychological outcomes after trauma. RESULTS: A third of health care workers experienced the pandemic as a potentially traumatic stress event; a greater proportion of health care workers experienced high levels of escalating stress. Predictive factors included sense of control, ability to manage work-life demands, guilt or shame, age, and level of education. Gender was no longer predictive after controlling for other factors. Escalating stress was especially high among nonclinical academics and clinical private practitioners. CONCLUSION: Findings suggest adverse effects on total worker health, care quality, professionalism, retention, and acute and chronic mental health.

CCL22 mutations drive natural killer cell lymphoproliferative disease by deregulating microenvironmental crosstalk.

Chronic lymphoproliferative disorder of natural killer cells (CLPD-NK) is characterized by clonal expansion of natural killer (NK) cells where the underlying genetic mechanisms are incompletely understood. In the present study, we report somatic mutations in the chemokine gene CCL22 as the hallmark of a distinct subset of CLPD-NK. CCL22 mutations were enriched at highly conserved residues, mutually exclusive of STAT3 mutations and associated with gene expression programs that resembled normal CD16dim/CD56bright NK cells. Mechanistically, the mutations resulted in ligand-biased chemokine receptor signaling, with decreased internalization of the G-protein-coupled receptor (GPCR) for CCL22, CCR4, via impaired ß-arrestin recruitment. This resulted in increased cell chemotaxis in vitro, bidirectional crosstalk with the hematopoietic microenvironment and enhanced NK cell proliferation in vivo in transgenic human IL-15 mice. Somatic CCL22 mutations illustrate a unique mechanism of tumor formation in which gain-of-function chemokine mutations promote tumorigenesis by biased GPCR signaling and dysregulation of microenvironmental crosstalk.

Characterization of dibenzo[a,l]pyrene-trans-11,12-diol (dibenzo[def,p]chrysene) glucuronidation by UDP-glucuronosyltransferases.

Dibenzo[a,l]pyrene (DB[a,l]P) (dibenzo[def,p]chrysene) is a highly carcinogenic polycyclic aromatic hydrocarbon (PAH) that has been identified in tobacco smoke and is found in our environment due to incomplete combustion of organic matter. Its metabolites are known to form stable DNA adducts in bacteria and mammalian cells, and can lead to tumors in animal models. Glucuronidation of major metabolites of DB[a,l]P by the uridine-5'-diphosphate glucuronosyltransferase (UGT) family of enzymes is an important route of detoxification of this pro-carcinogen. The focus of the current study was to characterize the glucuronidation of the pro-carcinogenic enantiomers DB[a,l]P-(+)-trans-11S,12S-diol and DB[a,l]P-(-)-trans-11R,12R-diol. Glucuronidation assays with HEK293 cell lines overexpressing individual human UGT enzymes demonstrated that UGTs 1A1, 1A4, 1A7, 1A8, 1A9, 1A10, and 2B7 glucuronidated one or both DB[a,l]P-trans-11,12-diol enantiomers. Three glucuronide conjugates were observed in activity assays with UGTs 1A1 and 1A10, while two glucuronides were formed by UGTs 1A7, 1A8, and 1A9, and one glucuronide was made by UGT1A4 and UGT2B7. Enzyme kinetic analysis indicated that UGT1A9 was the most efficient UGT at forming both the (+)-DB[a,l]P-11-Gluc and (-)-DB[a,l]P-11-Gluc products, while UGTs 1A1 and 1A10 were the most efficient at forming the (+)-DB[a,l]P-12-Gluc product (as determined by k(cat)/K(M)). Incubations with human liver microsomes showed the formation of three diastereomeric glucuronide products: (+)-DB[a,l]P-11-Gluc, (+)-DB[a,l]P-12-Gluc, and (-)-DB[a,l]P-11-Gluc, with an average overall ratio of 31:32:37 in four liver specimens. Human bronchus and trachea tissue homogenates demonstrated glucuronidation activity against both DB[a,l]P-trans-11,12-diol enantiomers, with both tissues producing the (+)-DB[a,l]P-11-Gluc and (+)-DB[a,l]P-12-Gluc with little or no formation of (-)-DB[a,l]P-11-Gluc. These results indicate that multiple UGTs are involved in the stereospecific glucuronidation of DB[a,l]P-trans-11,12-diol in a pattern consistent with their expression in respiratory tract tissues and that glucuronidation may be an important first-line detoxification mechanism of DB[a,l]P metabolites.

Mobilizing an institutional supportive response for healthcare workers and other staff in the context of COVID-19: The Yale experience.

The burden of the COVID-19 pandemic upon healthcare workers necessitates a systematic effort to support their resilience. This article describes the Yale University and Yale New Haven Health System effort to unite several independent initiatives into a coherent integrated model for institutional support for healthcare workers. Here, we highlight both opportunities and challenges faced in attempting to support healthcare workers during this pandemic.

Advances in the Diagnosis and Treatment of Large Granular Lymphocytic Leukemia.

PURPOSE OF REVIEW: The past decade in LGL leukemia research has seen increased pairing of clinical data with molecular markers, shedding new insights on LGL leukemia pathogenesis and heterogeneity. This review summarizes the current standard of care of LGL leukemia, updates from clinical trials, and our congruent improved understanding of LGL pathogenesis. RECENT FINDINGS: Various clinical reports have identified associations between stem, bone marrow, and solid organ transplants and incidence of LGL leukemia. There is also a potential for underdiagnosis of LGL leukemia within the rheumatoid arthritis patient population, emphasizing our need for continued study. Preliminary results from the BNZ-1 clinical trial, which targets IL-15 along with IL-2 and IL-9 signaling pathways, show some evidence of clinical response. With advances in our understanding of LGL pathogenesis from both the bench and the clinic, exciting avenues for investigations lie ahead for LGL leukemia.

Large granular lymphocyte leukemia serum and corresponding hematological parameters reveal unique cytokine and sphingolipid biomarkers and associations with STAT3 mutations.

Large granular lymphocyte (LGL) leukemia is a rare hematological disorder with expansion of the T-cell or natural killer (NK) cell lineage. Signal transducer and activator of transcription 3 (STAT3) exhibits somatic activating mutations in 30%-40% of LGL leukemia cases. Transcriptional targets of STAT3 include inflammatory cytokines, thus previous studies have measured cytokine levels of LGL leukemia patients compared to normal donors. Sphingolipid metabolism is a growing area of cancer research, with efforts focused on drug discovery. To date, no studies have examined serum sphingolipids in LGL leukemia patients, and only one study compared a subset of cytokines between the T-LGL and NK-LGL subtypes. Therefore, here, we included both LGL leukemia subtypes with the goals of (a) measuring serum sphingolipids for the first time, (b) measuring cytokines to find distinctions between the subtypes, and (c) establishing relationships with STAT3 mutations and clinical data. The serum analyses identified cytokines (EGF, IP-10, G-CSF) and sphingolipids (SMC22, SMC24, SMC20, LysoSM) significantly different in the LGL leukemia group compared to normal donors. In a mixed STAT3 mutation group, D661Y samples exhibited the highest mean corpuscular volume (MCV) values. We explored this further by expanding the cohort to include larger groups of single STAT3 mutations. Male D661Y STAT3 samples had lower Hgb and higher MCV compared to wild type (WT) or Y640F counterparts. This is the first report examining large groups of individual STAT3 mutations. Overall, our results revealed novel serum biomarkers and evidence that D661Y mutation may show different clinical manifestation compared to WT or Y640F STAT3.