Chronic myeloproliferative neoplasms and risk of osteoporotic fractures; a nationwide population-based cohort study

Risk of fractures and use of bisphosphonates in adult patients with immune thrombocytopenia-A nationwide population-based study

Corticosteroids remain the first-line treatment of immune thrombocytopenia (ITP), but increase the risk of osteoporosis and fractures. Bisphosphonates are used for the treatment of osteoporosis, but their usage among patients with ITP has not been systemically described. We investigated the risk of fractures and the use of bisphosphonates in adult patients with primary (pITP) and secondary ITP (sITP) compared with matched comparators in a nationwide registry-based cohort study. We identified 4030 patients with pITP (median age 60 years [IQR, 40-74]), 550 with sITP (median age 59 years [IQR, 43-74]) and 182 939 age-sex-matched general population comparators. All individuals were followed for incident fractures. Bisphosphonate use was estimated for calendar-years and in temporal relation to the ITP diagnosis. Adjusted cause-specific hazard ratio (csHR) for any fracture was 1.37 (95% confidence interval [CI] 1.23; 1.54) for pITP and 1.54 (1.17; 2.03) for sITP. The first-year csHR was 1.82 (1.39; 2.40) for pITP and 2.78 (1.58; 4.91) for sITP. Bisphosphonate use over calendar-years and in the early years following ITP diagnosis was higher among patients with ITP diagnosis compared with the general population. In conclusion, the risk of fractures and the use of bisphosphonates are higher in patients with ITP compared with the general population.

Revisiting Circulating Extracellular Matrix Fragments as Disease Markers in Myelofibrosis and Related Neoplasms

Philadelphia chromosome-negative chronic myeloproliferative neoplasms (MPNs) arise due to acquired somatic driver mutations in stem cells and develop over 10-30 years from the earliest cancer stages (essential thrombocythemia, polycythemia vera) towards the advanced myelofibrosis stage with bone marrow failure. The JAK2V617F mutation is the most prevalent driver mutation. Chronic inflammation is considered to be a major pathogenetic player, both as a trigger of MPN development and as a driver of disease progression. Chronic inflammation in MPNs is characterized by persistent connective tissue remodeling, which leads to organ dysfunction and ultimately, organ failure, due to excessive accumulation of extracellular matrix (ECM). Considering that MPNs are acquired clonal stem cell diseases developing in an inflammatory microenvironment in which the hematopoietic cell populations are progressively replaced by stromal proliferation-"a wound that never heals"-we herein aim to provide a comprehensive review of previous promising research in the field of circulating ECM fragments in the diagnosis, treatment and monitoring of MPNs. We address the rationales and highlight new perspectives for the use of circulating ECM protein fragments as biologically plausible, noninvasive disease markers in the management of MPNs.

Polypharmacy, Potentially Inappropriate Medications, and Drug-to-Drug Interactions in Patients with Chronic Myeloproliferative Neoplasms

Polypharmacy, potentially inappropriate medications (PIMs), and drug-to-drug interactions (DDIs) are highly prevalent in the elderly and may have adverse effects on health-related outcomes. Their occurrence and clinical and prognostic associations in patients with chronic myeloproliferative neoplasms (MPN) are unknown. We retrospectively evaluated polypharmacy, PIMs, and DDIs in a cohort of 124 MPN patients (essential thrombocythemia, ET = 63, polycythemia vera, PV = 44, myelofibrosis = 9, MPN unclassifiable = 8) from a single community hematology practice. There were 761 drug prescriptions with a median of five prescribed medications per patient. Polypharmacy, at least one PIM (calculated for persons >60 years of age, n = 101), and at least one DDI were recorded in 76 (61.3%), 46 (45.5%), and 77 (62.1%) of patients, respectively. Seventy-four (59.6%) and twenty-one (16.9%) patients had at least one C or at least one D interaction, respectively. Among other associations, polypharmacy and DDIs were associated with older age, management of disease-related symptoms, osteoarthritis/osteoporosis, and different CV disorders. In multivariate analyses adjusted for clinically meaningful parameters, both polypharmacy and DDIs were significantly associated with inferior overall survival (OS) and time to thrombosis (TTT), whereas PIMs had no significant associations with neither OS nor TTT. There were no associations with bleeding or transformation risks. Polypharmacy, DDIs, and PIMs are very frequent among MPN patients and may have important clinical associations.

Low bone mineral density and its related factors in adults with congenital heart disease in Vietnam: A cross‐sectional study

Background and Aims

Recent studies have highlighted the increased risk of low bone mineral density (BMD) in adults with cardiovascular disease. However, little is known about BMD in adults with congenital heart disease (CHD), particularly in developing countries. We hypothesized that factors related to BMD would lead to a high prevalence of low BMD in adults with CHD. This study aimed to determine the prevalence of low BMD and its related factors in Vietnamese adults with CHD.

Methods

We conducted a cross‐sectional study of 73 adults diagnosed with CHD in Vietnam. Low BMD was classified based on their site‐specific Z‐scores and T‐scores at the posteroanterior lumbar spine and left proximal femur. Logistic regression analyses were performed to evaluate factors related to low BMD.

Results

Low BMD was confirmed in one‐third of the adults with CHD. There were trends of more bone loss in certain parts of the body than in others, with the prevalence of low BMD at the sites of the lumbar vertebrae (L1‒L4) and left proximal femur (femoral neck, trochanteric femur, and intertrochanteric area) of 43.9%, 31.8%, 28.8%, 33.3%, 8.8%, 1.5%, and 6.1%, respectively. The prevalence of low BMD in the lumbar spine was significantly higher than that in the left proximal femur (34.3% vs. 2.9%, p < 0.001). Moreover, the prevalence of low BMD was significantly higher in adults with CHD than in those without polycythemia and vitamin D deficiency (55.6% vs. 20.9%, p = 0.001 and 46.2% vs. 19.4%, p = 0.002, respectively). A stratified multivariate logistic regression analysis revealed that low BMD was associated with polycythemia (odds ratio: 4.72; 95% confidence interval: 1.64–13.58, p = 0.004).

Conclusions

Low BMD is common among adults with CHD in Vietnam and related to polycythemia.

Molecular Mechanisms Involved in Hypoxia-Induced Alterations in Bone Remodeling

Bone is crucial for the support of muscles and the protection of vital organs, and as a reservoir of calcium and phosphorus. Bone is one of the most metabolically active tissues and is continuously renewed to adapt to the changes required for healthy functioning. To maintain normal cellular and physiological bone functions sufficient oxygen is required, as evidence has shown that hypoxia may influence bone health. In this scenario, this review aimed to analyze the molecular mechanisms involved in hypoxia-induced bone remodeling alterations and their possible clinical consequences. Hypoxia has been associated with reduced bone formation and reduced osteoblast matrix mineralization due to the hypoxia environment inhibiting osteoblast differentiation. A hypoxic environment is involved with increased osteoclastogenesis and increased bone resorptive capacity of the osteoclasts. Clinical studies, although with contradictory results, have shown that hypoxia can modify bone remodeling.

Myeloproliferative Disorders and its Effect on Bone Homeostasis: The Role of Megakaryocytes

Myeloproliferative Neoplasms (MPNs) are a heterogeneous group of chronic hematological diseases that arise from the clonal expansion of abnormal hematopoietic stem cells, of which Polycythemia Vera (PV), Essential Thrombocythemia (ET), and Primary Myelofibrosis (PMF) have been extensively reviewed in context of clonal expansion, fibrosis and other phenotypes. Here, we review current knowledge on the influence of different forms of MPN on bone health. Studies implicated various degrees of effect of different forms of MPN on bone density, and on osteoblast proliferation and differentiation, using murine models and human data. The majority of studies show that bone volume is generally increased in PMF patients, whereas it is slightly decreased or not altered in ET and PV patients, although possible differences between male and female phenotypes were not fully explored in most MPN forms. Osteosclerosis seen in PMF patients is a serious complication that can lead to bone marrow failure, and the loss of bone reported in some ET and PV patients can lead to osteoporotic fractures. Some MPN forms are associated with increased number of megakaryocytes (MKs), and several of the MK-associated factors in MPN are known to affect bone development. Here, we review known mechanisms involved in these processes, with focus on the role of MKs and secreted factors. Understanding MPN-associated changes in bone health could improve early intervention and treatment of this side effect of the pathology.

High platelet count is associated with low bone mineral density: The MrOS Sweden cohort

In elderly ambulatory men, high platelet and high neutrophil counts are related to low bone mineral density (BMD), after adjustment for relevant covariates. Low hemoglobin (hgb) is even associated with low BMD, but this relationship seems to be dependent on estradiol and osteocalcin.

PURPOSE

Blood and bone cells exist in close proximity to each other in the bone marrow. Accumulating evidence, from both preclinical and clinical studies, indicates that these cell types are interconnected. Our hypothesis was that BMD measurements are associated with blood count variables and bone remodeling markers.

METHODS

We analyzed blood count variables, bone remodeling markers, and BMD, in subjects from the MrOS cohort from Gothenburg, Sweden. Men with at least one blood count variable (hgb, white blood cell count, or platelet count) analyzed were included in the current analysis (n = 1005), median age 75.3 years (range 69-81 years).

RESULTS

Our results show that high platelet counts were related to low BMD at all sites (total hip BMD; r = - 0.11, P = 0.003). No statistically significant association was seen between platelet counts and bone remodeling markers. Neutrophil counts were negatively associated with total body BMD (r = - 0.09, P = 0.006) and total hip BMD (r = - 0.08, P = 0.010), and positively related to serum ALP (r = 0.15, P < 0.001). Hgb was positively related to total hip BMD (r = 0.16, P < 0.001), and negatively to serum osteocalcin (r = - 0.13, P < 0.001). The association between platelet and neutrophil counts and total hip BMD was statistically significant after adjustments for other covariates, but the association between hgb and total hip BMD was dependent on estradiol and osteocalcin.

CONCLUSIONS

Our observations support the hypothesis of an interplay between blood and bone components.

Risk of Inflammatory Bowel Disease in Patients with Chronic Myeloproliferative Neoplasms: A Danish Nationwide Cohort Study

Simple Summary

We wanted to investigate the risk of inflammatory bowel disease (IBD) in patients with Philadelphia-negative chronic myeloproliferative neoplasms (MPNs), since up to 50% of these patients experience gastrointestinal symptoms and several studies have suggested an association between hematological cancers and IBD. We included ∼8000 patients and ∼80,000 sex- and age-matched, non-MPN comparisons from the general population, and found that MPN patients were two to three times more likely to develop IBD, but the absolute risk of IBD was modest. In addition, MPN patients were also 40% more likely to have a prior diagnosis of IBD. Our results pose intriguing questions about the causal pathways linking MPN and IBD, which may include genetic, treatment-related and immune-mediated factors. Moreover, it shows that abdominal symptoms in MPN patients may not only be caused by an enlarged spleen or treatment side-effects. Conversely, persistent leucocytosis and/or increased platelets in IBD patients may reflect concomitant MPN.

Abstract

An association between hematological cancers and inflammatory bowel disease (IBD) has previously been suggested, but the risk of IBD in patients with myeloproliferative neoplasms (MPNs) is unknown. We conducted a nationwide population-based cohort study using Danish registries, to estimate the risk of IBD in individuals diagnosed with essential thrombocythemia, polycythemia vera, myelofibrosis or unclassifiable MPN during 1994–2013. MPN patients were matched 1:10 with sex- and age-matched comparisons. Everyone was followed until a diagnosis of IBD, death/emigration, or 31 December 2013. The risk of IBD overall and according to MPN subtype was calculated using Cox regression and presented as hazard ratios (HRs) with 95% confidence intervals (CI). Of 8207 MPN patients followed for 45,232 person-years, 80 were diagnosed with IBD (61 ulcerative colitis, 19 Crohn’s disease). The rate of IBD per 1000 person-years was 1.8 (95% CI:1.4–2.2) in patients vs. 0.8 (95% CI:0.7–0.8) in comparisons, and the absolute 10-year risk of IBD was 0.8% (95% CI:0.6–1.0) in patients vs. 0.4% (95% CI:0.4–0.5) in comparisons. The HR of IBD was 2.4 (95% CI:2.1–2.9) with similar HRs for ulcerative colitis and Crohn’s disease. MPN subtype risks varied from 2.1 (95% CI:1.6–2.7) to 2.8 (95% CI:2.1–3.7). Our unselected cohort study showed a more than 2-fold increased risk of IBD in MPN patients.

Erythropoietin regulates metabolic response in mice via receptor expression in adipose tissue, brain, and bone

Erythropoietin (EPO) acts by binding to erythroid progenitor cells to regulate red blood cell production. While EPO receptor (Epor) expression is highest on erythroid tissue, animal models exhibit EPO activity in nonhematopoietic tissues, mediated, in part, by tissue-specific Epor expression. This review describes the metabolic response in mice to endogenous EPO and EPO treatment associated with glucose metabolism, fat mass accumulation, and inflammation in white adipose tissue and brain during diet-induced obesity and with bone marrow fat and bone remodeling. During high-fat diet-induced obesity, EPO treatment improves glucose tolerance, decreases fat mass accumulation, and shifts white adipose tissue from a pro-inflammatory to an anti-inflammatory state. Fat mass regulation by EPO is sex dimorphic, apparent in males and abrogated by estrogen in females. Cerebral EPO also regulates fat mass and hypothalamus inflammation associated with diet-induced obesity in males and ovariectomized female mice. In bone, EPO contributes to the balance between adipogenesis and osteogenesis in both male and female mice. EPO treatment promotes bone loss mediated via Epor in osteoblasts and reduces bone marrow adipocytes before and independent of change in white adipose tissue fat mass. EPO regulation of bone loss and fat mass is independent of EPO-stimulated erythropoiesis. EPO nonhematopoietic tissue response may relate to the long-term consequences of EPO treatment of anemia in chronic kidney disease and to the alternative treatment of oral hypoxia-inducible factor prolyl hydroxylase inhibitors that increase endogenous EPO production.

Highly increased risk of fracture in patients with myeloproliferative neoplasm

The risk for hip and vertebral fracture was determined in 10,752 patients diagnosed with myeloproliferative neoplasms (MPN) in Sweden 1995-2015. The mean follow-up time were 6.34 years. Five percent developed hip fracture and 1.3% a vertebral fracture. There was a significant increased risk for fracture among the MPN patients compared with the Swedish population. The ratio of observed (obs) and expected (exp) number of hip fracture in all MPN patients, polycythemia vera (PV), essential thrombocythemia and MPN undetermined (MPNu) was 1.20 (95% confidence interval (CI): 1.10-1.31), 1.37 (95% CI: 1.19-1.58), 1.02 (95% CI: 0.87-1.19), and 1.28 (95% CI: 1.07-1.52), respectively. Corresponding figures for vertebral fractures were 1.94 (95% CI: 1.64-2.29), 2.09 (95% CI: 1.56-2.75), 1.50 (95% CI: 1.06-2.07) and 2.47 (95% CI: 1.77-3.35), respectively. Patients with MPN had an increased risk of hip and vertebral fracture, especially patients with PV and MPNu in comparison with the entire Swedish population.

"Take My Bone Away?" Hypoxia and bone: A narrative review

To maintain normal cellular and physiological function, sufficient oxygen is required. Recently, evidence has suggested that hypoxia, either pathological or environmental, may influence bone health. It appears that bone cells are distinctly responsive to hypoxic stimuli; for better or worse, this is still yet to be elucidated. Hypoxia has been shown to offer potentially therapeutic effects for bone by inducing an osteogenic-angiogenic response, although, others have noted excessive osteoclastic bone resorption instead. Much evidence suggests that the hypoxic-inducible pathway is integral in mediating the changes in bone metabolism. Furthermore, many factors associated with hypoxia including changes in energy metabolism, acid-base balance and the increased generation of reactive oxygen species, are known to influence bone metabolism. This review aims to examine some of the putative mechanisms responsible for hypoxic-induced alterations of bone metabolism, with regard to osteoclasts and osteoblasts, both positive and negative.

Two-fold risk of pneumonia and respiratory mortality in individuals with myeloproliferative neoplasm: A population-based cohort study

BACKGROUND

High cardiovascular comorbidity contributes to excess mortality in patients with myeloproliferative neoplasm, while less is known about respiratory comorbidity and mortality. We tested the hypothesis that individuals with myeloproliferative neoplasm have increased risk of pneumonia and respiratory mortality.

METHODS

Of 249 294 invited individuals aged ≥20 from the Danish general population from 2003-2015, 107 900 participated and were included in the Copenhagen General Population Study (response-rate: 43%). We examined lung function and respiratory symptoms at baseline examination and followed individuals prospectively from baseline examination through 2018 to determine risk of pneumonia and respiratory mortality using Cox proportional hazard regression. Among 351 individuals with myeloproliferative neoplasm, 131 (37%) were diagnosed at baseline examination and 220 (63%) were diagnosed during follow-up. The follow-up cases were entered in the regression analysis by using a time-varying variable.

FINDINGS

In total, 125 (36%) individuals had essential thrombocythaemia, 124 (35%) had polycythaemia vera, and 102 (29%) had myelofibrosis/unclassifiable myeloproliferative neoplasm. During follow-up we observed 5979 pneumonias and 2278 respiratory deaths. Compared to individuals without myeloproliferative neoplasm, multivariable adjusted hazard ratios in individuals with myeloproliferative neoplasm were 2·18 (95% CI: 1·60-2·96) for pneumonia and 2·27 (1·46-3·53) for respiratory mortality. Corresponding hazard ratios were 1·26 (0·71-2·30) and 0·96 (0·31-2·94) for essential thrombocythaemia, 2·50 (1·57-3·98) and 3·58 (1·94-6·59) for polycythaemia vera, and 3·03 (1·86-4·93) and 2·40 (1·11-5·19) for myelofibrosis/unclassifiable myeloproliferative neoplasm, respectively. Results were similar in those with and without airflow limitation, and in never-smokers and ever-smokers separately.

INTERPRETATION

Individuals with myeloproliferative neoplasm had two-fold increased risk of pneumonia and respiratory mortality, mainly due to polycythaemia vera and myelofibrosis/unclassifiable myeloproliferative neoplasm. These are novel findings.

The Many Facets of Erythropoietin Physiologic and Metabolic Response

In mammals, erythropoietin (EPO), produced in the kidney, is essential for bone marrow erythropoiesis, and hypoxia induction of EPO production provides for the important erythropoietic response to ischemic stress, such as during blood loss and at high altitude. Erythropoietin acts by binding to its cell surface receptor which is expressed at the highest level on erythroid progenitor cells to promote cell survival, proliferation, and differentiation in production of mature red blood cells. In addition to bone marrow erythropoiesis, EPO causes multi-tissue responses associated with erythropoietin receptor (EPOR) expression in non-erythroid cells such neural cells, endothelial cells, and skeletal muscle myoblasts. Animal and cell models of ischemic stress have been useful in elucidating the potential benefit of EPO affecting maintenance and repair of several non-hematopoietic organs including brain, heart and skeletal muscle. Metabolic and glucose homeostasis are affected by endogenous EPO and erythropoietin administration affect, in part via EPOR expression in white adipose tissue. In diet-induced obese mice, EPO is protective for white adipose tissue inflammation and gives rise to a gender specific response in weight control associated with white fat mass accumulation. Erythropoietin regulation of fat mass is masked in female mice due to estrogen production. EPOR is also expressed in bone marrow stromal cells (BMSC) and EPO administration in mice results in reduced bone independent of the increase in hematocrit. Concomitant reduction in bone marrow adipocytes and bone morphogenic protein suggests that high EPO inhibits adipogenesis and osteogenesis. These multi-tissue responses underscore the pleiotropic potential of the EPO response and may contribute to various physiological manifestations accompanying anemia or ischemic response and pharmacological uses of EPO.

Erythropoiesis, EPO, macrophages, and bone

The regulation of erythropoiesis in the bone marrow microenvironment is a carefully orchestrated process that is dependent upon both systemic and local cues. Systemic erythropoietin (EPO) production by renal interstitial cells plays a critical role in maintaining erythropoietic homeostasis. In addition, there is increasing clinical and preclinical data linking changes in EPO and erythropoiesis to altered skeletal homeostasis, suggesting a functional relationship between the regulation of erythropoiesis and bone homeostasis. As key local components of the bone marrow microenvironment and erythropoietic niche, macrophage subsets play important roles in both processes. In this review, we summarize our current understanding of the cellular and molecular mechanisms that may facilitate the coordinated regulation of erythropoiesis and bone homeostasis.

Perspectives on interferon-alpha in the treatment of polycythemia vera and related myeloproliferative neoplasms: minimal residual disease and cure?

The first clinical trials of the safety and efficacy of interferon-alpha2 (IFN-alpha2) were performed about 30 years ago. Since then, several single-arm studies have convincingly demonstrated that IFN-alpha2 is a highly potent anti-cancer agent in several cancer types but unfortunately not being explored sufficiently due to a high toxicity profile when using non-pegylated IFN-alpha2 or high dosages or due to competitive drugs, that for clinicians at first glance might look more attractive. Within the hematological malignancies, IFN-alpha2 has only recently been revived in patients with the Philadelphia-negative myeloproliferative neoplasms-essential thrombocytosis, polycythemia vera, and myelofibrosis (MPNs)-and in patients with chronic myelogenous leukemia (CML) in combination with tyrosine kinase inhibitors. In this review, we tell the IFN story in MPNs from the very beginning in the 1980s up to 2018 and describe the perspectives for IFN-alpha2 treatment of MPNs in the future. The mechanisms of actions are discussed and the impact of chronic inflammation as the driving force for clonal expansion and disease progression in MPNs is discussed in the context of combination therapies with potent anti-inflammatory agents, such as the JAK1-2 inhibitors (licensed only ruxolitinib) and statins as well. Interferon-alpha2 being the cornerstone treatment in MPNs and having the potential of inducing minimal residual disease (MRD) with normalization of the bone marrow and low-JAK2V617F allele burden, we believe that combination therapy with ruxolitinib may be even more efficacious and hopefully revert disease progression in many more patients to enter the path towards MRD. In patients with advanced and transforming disease towards leukemic transformation or having transformed to acute myeloid leukemia, "triple therapy" is proposed as a novel treatment modality to be tested in clinical trials combining IFN-alpha2, DNA-hypomethylator, and ruxolitinib. The rationale for this "triple therapy" is given, including the fact that even in AML, IFN-alpha2 as monotherapy may revert disease progression. We envisage a new and bright future with many more patients with MPNs obtaining MRD on the above therapies. From this stage-and even before-vaccination strategies may open a new horizon with cure being the goal for some patients.

Bone loss and hematological malignancies in adults: a pilot study

PURPOSE

Bone loss-osteopenia and osteoporosis-is a recognized consequence of solid tumors in adults, of pediatric hematological malignancies, and of the treatment for these diseases, but little research has been published on the adverse effects of hematological malignancies on the bone in adults. The aim of this study is to identify hematological diseases that are associated with the highest prevalence and severity of osteoporosis.

METHODS

We evaluated DXA (dual-energy X-ray absorptiometry) in a cross-section of 181 adult patients with hematological neoplasms, excluding multiple myeloma. All patients were over 18 years of age, signed a local institutional review board (IRB)-approved consent form, and had completed a questionnaire regarding predisposing factors to osteoporosis. This data was supplemented by hospital charts.

RESULTS

Bone loss as measured by DXA T scores was found in 65% of patients, of whom 38% had osteopenia and 27% osteoporosis. DXA Z scores under - 2.0 were found in 11.4% of patients, compared to the expected 2.5% of the normal population. The DXA Z scores varied by diagnosis, showing bone loss in 49% of chronic lymphocytic leukemia/small lymphocytic lymphoma, compared to 67% of non-Hodgkin lymphoma and 88% of Hodgkin disease; the scores were not affected by the duration of time from diagnosis to DXA (3.6, 2.0, and 1.6 years, respectively).

CONCLUSION

Adult patients with hematological malignancies have significant bone loss compared to a normal age-matched population. The type of diagnosis is more important than the time from diagnosis in predicting risk for bone loss. Recognition of bone loss in these patients may warrant prophylactic measures and lifestyle changes before, during, and after therapy.

Long-Term Side Effects of Tyrosine Kinase Inhibitors in Chronic Myeloid Leukemia

Most patients with chronic myeloid leukemia have deep and durable responses when treated with BCR-ABL1 tyrosine kinase inhibitors (TKIs). Imatinib (the first approved TKI), nilotinib, and dasatinib are used in newly diagnosed, relapsed or intolerant patients, while bosutinib and ponatinib are used only in relapsed or intolerant patients. Previously the drug of choice was related to the likelihood of response and, to a small extent, patient comorbidities. The long-term toxicities, particularly cardiopulmonary side effects, are now impacting treatment choice, making patient comorbidities of significant concern. About 10 % of patients do not tolerate their initial BCR-ABL1 TKI and an increasing number are developing long-term side effects, particularly with the second generation drugs. Side effects of the five drugs reviewed here highlight the differences between cardiovascular, pulmonary, gastrointestinal, and endocrine toxicities, as well as possible second malignancies. There is increasing evidence that patients whose disease is controlled by TKI's will have greater impact on their quality of life from comorbidities or drug adverse events than from the disease itself. Research into management of long-term toxicities is needed.

Age-Related Macular Degeneration in Patients With Chronic Myeloproliferative Neoplasms

Importance

It has been suggested that systemic inflammation increases the risk of age-related macular degeneration (AMD). Given that chronic immune modulation is present in patients with myeloproliferative neoplasms (MPNs), the risk of AMD in these patients may be increased.

Objective

To compare the risk of AMD in patients with MPNs with the risk of AMD in matched controls from the general population.

Design, Setting, and Participants

A nationwide population-based cohort study using Danish registers was conducted of all patients in Denmark who received a diagnosis between January 1, 1994, and December 31, 2013, of essential thrombocythemia, polycythemia vera, myelofibrosis, or unclassifiable MPNs. For each patient, 10 age- and sex-matched controls were included. All patients without prior AMD were followed up from the date of diagnosis (or corresponding entry date for the controls) until the first AMD diagnosis, death or emigration, or December 31, 2013, whichever occurred first. Data analysis was performed from April 1, 2015, to October 31, 2016.

Main Outcomes and Measures

Incidence of AMD recorded in specialized hospital-based care. The rates and absolute risk of AMD were calculated. Using Cox proportional hazards regression models, smoking and risk-time adjusted hazard ratios (HRs) between patients and controls were calculated. In addition, HRs of neovascular AMD after 2006 were calculated since antivascular endothelial growth factor treatment was introduced nationwide at hospitals thereafter.

Results

A total of 7958 patients with MPNs (4279 women [53.8%] and 3679 men [46.2%]; mean [SD] age at diagnosis, 66.4 [14.3] years) were included in the study. The rate of AMD per 1000 person-years at risk was 5.2 (95% CI, 4.6-5.9) for patients with MPNs (2628 with essential thrombocythemia, 3063 with polycythemia vera, 547 with myelofibrosis, and 1720 with unclassifiable MPNs) and 4.3 (95% CI, 4.1-4.4) for the 77 445 controls, while the 10-year risk of AMD was 2.4% (95% CI, 2.1%-2.8%) for patients with MPNs and 2.3% (95% CI, 2.2%-2.4%) for the controls. The risk of AMD was increased overall for patients with MPNs (adjusted HR, 1.3; 95% CI, 1.1-1.5), with adjusted HRs for the subtypes of 1.2 (95% CI, 1.0-1.6) for essential thrombocythemia, 1.4 (95% CI, 1.2-1.7) for polycythemia vera, 1.7 (95% CI, 0.8-4.0) for myelofibrosis, and 1.5 (95% CI, 1.1-2.1) for unclassifiable MPNs. In addition, patients with MPNs had a higher risk of neovascular AMD (adjusted HR, 1.4; 95% CI, 1.2-1.6).

Conclusions and Relevance

Our results suggest that patients with MPNs are at increased risk of AMD, supporting the possibility that systemic inflammation is involved in the pathogenesis of AMD.

Interleukin-1β as emerging therapeutic target in hematological malignancies and potentially in their complications

Interleukin-1β (IL-1β) is a pleiotropic cytokine that exerts multiple roles in both physiological and pathological conditions. It is produced by different cell subsets, and drives a wide range of inflammatory responses in numerous target cells. Enhanced IL-1β signaling is a common event in patients of hematological malignancies. Recent body of evidence obtained in preclinical models shows the pathogenic role of these alterations, and the promising therapeutic value of IL-1 targeting. In this review, we further highlight a potential contribution of IL-1β linking to complications and autoimmune disease that should be investigated in future studies. Hence, drugs that target IL-1 may be helpful to improve outcome or reduce morbidity in patients. Some of them are FDA-approved, and used efficiently against autoimmune diseases, like IL-1 receptor antagonist. In the clinic, however, this agent seems to have limited properties. Current improved drugs will allow to determine the true potential of IL-1 and IL-1β targeting as therapy in hematological malignancies and their related complications.

Bone Health in Patients With Hematopoietic Disorders of Bone Marrow Origin: Systematic Review and Meta- Analysis

Blood cell production and bone homeostasis are physically interlinked systems that exhibit active cross-talk. We examined how bone health is affected in patients with hematopoietic disorders due to abnormal proliferation of bone marrow cells. The electronic databases Medline, Embase, PubMed, BIOSIS Previews, Web of Science, and Cochrane were searched for studies presenting numerical values for trabecular bone volume or bone mineral density in control and patients with hematopoietic disorders. We identified 5 studies for beta-thalassemia, 6 for sickle cell anemia, 2 for polycythemia vera and essential thrombocythemia, 3 for chronic myelogenous leukemia, 6 for myelofibrosis, 5 for multiple myeloma, and 4 studies each for systemic mastocytosis, lymphocytic leukemia, and hemochromatosis. The effect of the disease state on bone density was significant and negative for beta-thalassemia (r = -2.00; 95% confidence interval [CI] -3.41, -0.58; p < 0.005), sickle cell anemia (-0.91; -1.36, -0.47; p < 0.00005), chronic myelogenous leukemia (-0.55; -0.88, -0.22; p < 0005), mastocytosis (-0.99; -1.16, -0.82; p < 0.00001), lymphoblastic leukemia (-0.69; -0.98, -0.40; p < 0.00001), multiple myeloma (-0.67; -0.99, -0.35; p < 0.00005), and hemochromatosis (-1.15; -1.64, -0.66; p < 0.00001). The changes were negative but not significant for polycythemia vera (-0.16; -0.38, 0.05; p = 0.069) and essential thrombocythemia (-0.33; -0.92, 0.26; p = 0.14). In myelofibrosis, disease state was associated with increased bone density (0.74; 0.12, 1.36; p < 0.05). Bone density change significantly and negatively correlated with the level of ferritin and bone marrow cellularity but not with hemoglobin or erythropoietin. Thus, independent of hematopoietic lineage, abnormal proliferation of bone marrow cells appears to be associated with bone loss. Iron metabolism may independently contribute to bone homeostasis. © 2016 American Society for Bone and Mineral Research.

Interleukin 3- receptor targeted exosomes inhibit in vitro and in vivo Chronic Myelogenous Leukemia cell growth

Despite Imatinib (IM), a selective inhibitor of Bcr-Abl, having led to improved prognosis in Chronic Myeloid Leukemia (CML) patients, acquired resistance and long-term adverse effects is still being encountered. There is, therefore, urgent need to develop alternative strategies to overcome drug resistance.

According to the molecules expressed on their surface, exosomes can target specific cells. Exosomes can also be loaded with a variety of molecules, thereby acting as a vehicle for the delivery of therapeutic agents.

In this study, we engineered HEK293T cells to express the exosomal protein Lamp2b, fused to a fragment of Interleukin 3 (IL3). The IL3 receptor (IL3-R) is overexpressed in CML blasts compared to normal hematopoietic cells and thus is able to act as a receptor target in a cancer drug delivery system. Here we show that IL3L exosomes, loaded with Imatinib or with BCR-ABL siRNA, are able to target CML cells and inhibit in vitro and in vivo cancer cell growth.

Bone mineral density and microarchitecture in patients with essential thrombocythemia and polycythemia vera

In this cross-sectional study of 45 patients with myeloproliferative neoplasms, we found no evidence of secondary osteoporosis.

INTRODUCTION

Patients with essential thrombocythemia (ET) and polycythaemia vera (PV) are at increased risk of fractures but the underlying mechanisms have not been settled. We conducted a study to assess bone mineral density, microarchitecture, estimated bone strength and global bone turnover in 45 patients with ET or PV.

METHODS

Patients were evaluated in a cross-sectional study with dual energy X-ray absorptiometry (DXA) at the hip and spine; high-resolution peripheral quantitative computed tomography (HR-pQCT) at the distal radius and distal tibia; and biochemical markers of bone turnover including pro-collagen type 1 N-terminal pro-peptide, osteocalcin, C-terminal cross-linking telopeptide of type 1 collagen and bone-specific alkaline phosphatase. Also, 45 healthy comparisons, matched on age, height and weight with each patient were included as control subjects.

RESULTS

Patients and comparisons had almost identical BMDs: 0.96 (IQR: 0.85-1.07) g/cm² and 0.96 g/cm² (IQR: 0.86-1.05 g/cm²), respectively. As well all microarchitecture and estimated bone strength measures were highly similar in the two groups. Levels of bone turnover markers were within reference values in patients.

CONCLUSION

These results reveal no evidence of secondary osteoporosis among patients with ET or PV. The mechanism behind the increased fracture risk in ET or PV patients remains unknown.

Polycythemia is associated with bone loss and reduced osteoblast activity in mice

Increased fragility has been described in humans with polycythemia vera (PV). Herein, we describe an osteoporotic phenotype associated with decreased osteoblast activity in a mouse model of PV and another mouse of polycythemia and elevated circulating erythropoietin (EPO). Our results are important for patients with PV or those treated with recombinant EPO (rEPO).

INTRODUCTION

PV and other myeloproliferative syndromes have been recently associated with an increased risk for fractures. However, the presence of osteoporosis in these patients has not been well documented. EPO, a hormone primarily known to stimulate erythropoiesis, has been shown recently to regulate bone homeostasis in mice. The aim of this study was to examine the bone phenotype of a mouse model of PV and compare it to that of animals with polycythemia caused by elevated circulating EPO.

METHODS

Bone mass and remodeling were evaluated by micro-computed tomography and histomorphometry. The JAK2(V617F) knock-in mouse, a model of human PV, manifests polycythemia and low circulating EPO levels. Results from this mouse were compared to wild type (wt) controls and the tg6 transgenic mouse that shows polycythemia caused by increased constitutive expression of EPO.

RESULTS

Compared to wt, both JAK2(V617F) and tg6 mice had a decrease in trabecular bone mass. Tg6 mice showed an additional modest decrease in cortical thickness and cortical bone volume per tissue volume (P < 0.01) suggesting a more severe bone phenotype than JAK2(V617F). Decreased osteoblast numbers and bone formation along with normal osteoclast numbers and activity were found in both mice.

CONCLUSIONS

This study indicates that PV is associated with low bone mass and decreased osteoblast activity in mice. Our results support future studies of osteoporosis in affected humans. Polycythemia caused by chronically elevated circulating EPO also results in bone loss, and implications on patients treated with rEPO should be evaluated.

MPNs as Inflammatory Diseases: The Evidence, Consequences, and Perspectives

In recent years the evidence is increasing that chronic inflammation may be an important driving force for clonal evolution and disease progression in the Philadelphia-negative myeloproliferative neoplasms (MPNs), essential thrombocythemia (ET), polycythemia vera (PV), and myelofibrosis (MF). Abnormal expression and activity of a number of proinflammatory cytokines are associated with MPNs, in particular MF, in which immune dysregulation is pronounced as evidenced by dysregulation of several immune and inflammation genes. In addition, chronic inflammation has been suggested to contribute to the development of premature atherosclerosis and may drive the development of other cancers in MPNs, both nonhematologic and hematologic. The MPN population has a substantial inflammation-mediated comorbidity burden. This review describes the evidence for considering the MPNs as inflammatory diseases, A Human Inflammation Model of Cancer Development, and the role of cytokines in disease initiation and progression. The consequences of this model are discussed, including the increased risk of second cancers and other inflammation-mediated diseases, emphasizing the urgent need for rethinking our therapeutic approach. Early intervention with interferon-alpha2, which as monotherapy has been shown to be able to induce minimal residual disease, in combination with potent anti-inflammatory agents such as JAK-inhibitors is foreseen as the most promising new treatment modality in the years to come.

Bone geometry, bone mineral density, and micro-architecture in patients with myelofibrosis: a cross-sectional study using DXA, HR-pQCT, and bone turnover markers

Primary myelofibrosis (MF) is a severe chronic myeloproliferative neoplasm, progressing towards a terminal stage with insufficient haematopoiesis and osteosclerotic manifestations. Whilst densitometry studies have showed MF patients to have elevated bone mineral density, data on bone geometry and micro-structure assessed with non-invasive methods are lacking. We measured areal bone mineral density (aBMD) using dual-energy X-ray absorptiometry (DXA). Bone geometry, volumetric BMD, and micro-architecture were measured using high-resolution peripheral quantitative computed tomography (HR-pQCT). We compared the structural parameters of bones by comparing 18 patients with MF and healthy controls matched for age, sex, and height. Blood was analysed for biochemical markers of bone turnover in patients with MF. There were no significant differences in measurements of bone geometry, volumetric bone mineral density, and micro-structure between MF patients and matched controls. Estimated bone stiffness and bone strength were similar between MF patients and controls. The level of pro-collagen type 1 N-terminal pro-peptide (P1NP) was significantly increased in MF, which may indicate extensive collagen synthesis, one of the major diagnostic criteria in MF. We conclude that bone mineral density, geometry, and micro-architecture in this cohort of MF patients are comparable with those in healthy individuals.

Perspectives on the impact of JAK-inhibitor therapy upon inflammation-mediated comorbidities in myelofibrosis and related neoplasms

Chronic inflammation is suggested to contribute to the Philadelphia-chromosome-negative myeloproliferative neoplasm (MPN) disease initiation and progression, as well as the development of premature atherosclerosis and may drive the development of other cancers in MPNs, both nonhematologic and hematologic. The MPN population has a substantial comorbidity burden, including cerebral, cardiovascular, pulmonary, abdominal, renal, metabolic, skeletal, autoimmune, and chronic inflammatory diseases. This review describes the comorbidities associated with MPNs and the potential impact of early intervention with anti-inflammatory and/or immunomodulatory agents such as JAK-inhibitors, statins, and IFN-α to inhibit cancer progression and reduce MPN-associated comorbidity impact. Early intervention may yield a subset of patients who achieve minimal residual disease, thereby likely reducing the comorbidity burden and improving the cost-effective socioeconomic profile.