Obesity, weight gain, and risk of chronic myeloid leukemia

Higher prevalence of harbouring BCR::ABL1 in first-degree relatives of chronic myeloid leukaemia (CML) patients compared to normal population

BACKGROUND

The role of familial influence in chronic myeloid leukaemia (CML) occurrence is less defined. Previously, we conducted a study to determine the prevalence of harbouring BCR::ABL1 in our local adult normal population (designated as StudyN). We present our current study, which investigated the prevalence of harbouring BCR::ABL1 in the normal first-degree relatives of local CML patients (designated as StudyR). We compared and discussed the prevalence of StudyR and StudyN to assess the familial influence in CML occurrence.

METHODS

StudyR was a cross-sectional study using convenience sampling, recruiting first-degree relatives of local CML patients aged ≥ 18 years old without a history of haematological tumour. Real-time quantitative polymerase chain reaction standardised at the International Scale (BCR::ABL1-qPCRIS) was performed according to standard laboratory practice and the manufacturer's protocol.

RESULTS

A total of 96 first-degree relatives from 41 families, with a mean age of 39 and a male-to-female ratio of 0.88, were enrolled and analysed. The median number of relatives per family was 2 (range 1 to 5). Among them, 18 (19%) were parents, 39 (41%) were siblings, and 39 (41%) were offspring of the CML patients. StudyR revealed that the prevalence of harbouring BCR::ABL1 in the first-degree relatives was 4% (4/96), which was higher than the prevalence in the local normal population from StudyN, 0.5% (1/190). All four positive relatives were Chinese, with three of them being female (p > 0.05). Their mean age was 39, compared to 45 in StudyN. The BCR::ABL1-qPCRIS levels ranged between 0.0017%IS and 0.0071%IS, similar to StudyN (0.0023%IS to 0.0032%IS) and another study (0.006%IS to 0.016%IS).

CONCLUSION

Our study showed that the prevalence of harbouring BCR::ABL1 in the first-degree relatives of known CML patients was higher than the prevalence observed in the normal population. This suggests that familial influence in CML occurrence might exist but could be surpassed by other more dominant influences, such as genetic dilutional effects and protective genetic factors. The gender and ethnic association were inconsistent with CML epidemiology, suggestive of a higher familial influence in female and Chinese. Further investigation into this topic is warranted, ideally through larger studies with longer follow-up periods.

Homoharringtonine: updated insights into its efficacy in hematological malignancies, diverse cancers and other biomedical applications

HHT has emerged as a notable compound in the realm of cancer treatment, particularly for hematological malignancies. Its multifaceted pharmacological properties extend beyond traditional applications, warranting an extensive review of its mechanisms and efficacy. This review aims to synthesize comprehensive insights into the efficacy of HHT in treating hematological malignancies, diverse cancers, and other biomedical applications. It focuses on elucidating the molecular mechanisms, therapeutic potential, and broader applications of HHT. A comprehensive search for peer-reviewed papers was conducted across various academic databases, including ScienceDirect, Web of Science, Scopus, American Chemical Society, Google Scholar, PubMed/MedLine, and Wiley. The review highlights HHT's diverse mechanisms of action, ranging from its role in leukemia treatment to its emerging applications in managing other cancers and various biomedical conditions. It underscores HHT's influence on cellular processes, its efficacy in clinical settings, and its potential to alter pathological pathways. HHT demonstrates significant promise in treating various hematological malignancies and cancers, offering a multifaceted approach to disease management. Its ability to impact various physiological pathways opens new avenues for therapeutic applications. This review provides a consolidated foundation for future research and clinical applications of HHT in diverse medical fields.

Obesity and Leukemia: Biological Mechanisms, Perspectives, and Challenges

PURPOSE OF REVIEW

To examine the epidemiological data on obesity and leukemia; evaluate the effect of obesity on leukemia outcomes in childhood acute lymphoblastic leukemia (ALL) survivors; assess the potential mechanisms through which obesity may increase the risk of leukemia; and provide the effects of obesity management on leukemia. Preventive (diet, physical exercise, obesity pharmacotherapy, bariatric surgery) measures, repurposing drugs, candidate therapeutic agents targeting oncogenic pathways of obesity and insulin resistance in leukemia as well as challenges of the COVID-19 pandemic are also discussed.

RECENT FINDINGS

Obesity has been implicated in the development of 13 cancers, such as breast, endometrial, colon, renal, esophageal cancers, and multiple myeloma. Leukemia is estimated to account for approximately 2.5% and 3.1% of all new cancer incidence and mortality, respectively, while it represents the most frequent cancer in children younger than 5 years. Current evidence indicates that obesity may have an impact on the risk of leukemia. Increased birthweight may be associated with the development of childhood leukemia. Obesity is also associated with worse outcomes and increased mortality in leukemic patients. However, there are several limitations and challenges in meta-analyses and epidemiological studies. In addition, weight gain may occur in a substantial number of childhood ALL survivors while the majority of studies have documented an increased risk of relapse and mortality among patients with childhood ALL and obesity. The main pathophysiological pathways linking obesity to leukemia include bone marrow adipose tissue; hormones such as insulin and the insulin-like growth factor system as well as sex hormones; pro-inflammatory cytokines, such as IL-6 and TNF-α; adipocytokines, such as adiponectin, leptin, resistin, and visfatin; dyslipidemia and lipid signaling; chronic low-grade inflammation and oxidative stress; and other emerging mechanisms. Obesity represents a risk factor for leukemia, being among the only known risk factors that could be prevented or modified through weight loss, healthy diet, and physical exercise. Pharmacological interventions, repurposing drugs used for cardiometabolic comorbidities, and bariatric surgery may be recommended for leukemia and obesity-related cancer prevention.

Physical exercise recommendations for patients with chronic myeloid leukemia based on individual preferences identified in a large international patient survey study of the East German Study Group for Hematology and Oncology (OSHO #97)

Background

Tyrosine kinase inhibitors (TKIs) have significantly lowered mortality of chronic myeloid leukemia (CML) patients adjusting life expectancy to that of the standard population. However, CML and its treatment with TKIs causes a high disease burden. Physical exercise (PE) could be a non-pharmacological approach to reducing these and improving quality of life.

Purpose

The aim of this study was to determine the individual disease burden as well as PE preferences of CML patients and to deduce thereof specific PE recommendations.

Methods

This multicenter survey was conducted in cooperation with the LeukaNET/Leukemia-patient network including CML patients aged ≥18 years (German Registry of Clinical Trials, DRKS00023698). The severity of selected symptoms was assessed using the adapted Myeloproliferative Neoplasms Symptom Assessment Form: 0 (absent), 1-30 (mild), 31-70 (moderate), or 71-100 (severe). Information about patients' PE needs and preferences depending on their motivation was recorded.

Results

A total of 212 questionnaires were analyzed (52% female, median age 54 years). The prevalence of moderate-to-severe symptoms was 49% for fatigue, 40% for musculoskeletal pain, and 37% for concentration problems. Other commonly reported symptoms included skin reactions (42%) and weight gain (24%). The proportion of overweight/obese patients was 52%. Half of all respondents requested more information regarding PE. Patients with CML preferred individual training (82%), located outdoors (71%), at home (47%), or in an indoor swimming pool (31%). Regarding the training frequency, sports-inactive patients preferred a frequency of 1-2 training sessions per week, whereas sports-active patients preferred 3-4 sessions per week (p <0.001). Sports-inactive patients preferred a training time of 15-45 minutes, while sports-active patients preferred 30-60 minutes (p = 0.002). Subsequently, PE recommendations were developed for patients with CML. Combined resistance and endurance training (moderate intensity twice per week for 30 minutes) was recommended for beginners. Obese patients should prioritize joint-relieving sports. To reduce the risk of skin reactions, direct sunlight and possibly water sports should be avoided, and UV protection should be used.

Conclusion

Counseling and motivation of CML patients to be physically active should be part of the standard of care as well as support for implementation.

The Effect of Obesity and Body Mass Index on Hematologic Malignancies

A thorough examination of the available literature has revealed a well-established association of obesity and high body mass index (BMI) with an increased risk of various types of cancers, including hematologic malignancies. Specifically, the studies reviewed indicate a clear correlation between obesity and an increased risk of leukemias, lymphomas, multiple myeloma, myelodysplastic syndrome, and myeloproliferative diseases. Despite the established association of obesity and high BMI with hematologic malignancies, the underlying mechanisms remain largely undetermined. The development of hematologic malignancies may be influenced by several mechanisms associated with obesity and high BMI, including chronic inflammation, hormonal imbalances, adiposopathies, and metabolic dysregulation. Furthermore, there is mounting evidence indicating that obesity and high BMI may have a negative impact on the response to treatment and overall survival in patients with hematologic malignancies. This article aims to increase awareness and summarize the current state of research on the impact of obesity on hematologic malignancies, including the mechanisms by which obesity may influence the development and progression of these diseases. In addition, the current review highlights the need for effective weight management strategies in patients with hematologic malignancies to improve outcomes and mitigate the risk of complications.

GWAS-Identified Variants for Obesity Do Not Influence the Risk of Developing Multiple Myeloma: A Population-Based Study and Meta-Analysis

Multiple myeloma (MM) is an incurable disease characterized by the presence of malignant plasma cells in the bone marrow that secrete specific monoclonal immunoglobulins into the blood. Obesity has been associated with the risk of developing solid and hematological cancers, but its role as a risk factor for MM needs to be further explored. Here, we evaluated whether 32 genome-wide association study (GWAS)-identified variants for obesity were associated with the risk of MM in 4189 German subjects from the German Multiple Myeloma Group (GMMG) cohort (2121 MM cases and 2068 controls) and 1293 Spanish subjects (206 MM cases and 1087 controls). Results were then validated through meta-analysis with data from the UKBiobank (554 MM cases and 402,714 controls) and FinnGen cohorts (914 MM cases and 248,695 controls). Finally, we evaluated the correlation of these single nucleotide polymorphisms (SNPs) with cQTL data, serum inflammatory proteins, steroid hormones, and absolute numbers of blood-derived cell populations (n = 520). The meta-analysis of the four European cohorts showed no effect of obesity-related variants on the risk of developing MM. We only found a very modest association of the POC5_rs2112347G and ADCY3_rs11676272G alleles with MM risk that did not remain significant after correction for multiple testing (per-allele OR = 1.08, p = 0.0083 and per-allele OR = 1.06, p = 0.046). No correlation between these SNPs and functional data was found, which confirms that obesity-related variants do not influence MM risk.

Management of Hematologic Malignancies in the Era of COVID-19 Pandemic: Pathogenetic Mechanisms, Impact of Obesity, Perspectives, and Challenges

The COVID-19 pandemic brought about an unprecedented societal and healthcare system crisis, considerably affecting healthcare workers and patients, particularly those with chronic diseases. Patients with hematologic malignancies faced a variety of challenges, pertinent to the nature of an underlying hematologic disorder itself as well as its therapy as a risk factor for severe SARS-CoV-2 infection, suboptimal vaccine efficacy and the need for uninterrupted medical observation and continued therapy. Obesity constitutes another factor which was acknowledged since the early days of the pandemic that predisposed people to severe COVID-19, and shares a likely causal link with the pathogenesis of a broad spectrum of hematologic cancers. We review here the epidemiologic and pathogenetic features that obesity and hematologic malignancies share, as well as potential mutual pathophysiological links predisposing people to a more severe SARS-CoV-2 course. Additionally, we attempt to present the existing evidence on the multi-faceted crucial challenges that had to be overcome in this diverse patient group and discuss further unresolved questions and future challenges for the management of hematologic malignancies in the era of COVID-19.

Clinicopathological Variables and Outcome in Chronic Myeloid Leukemia Associated With BCR-ABL1 Transcript Type and Body Weight: An Outcome of European LeukemiaNet Project

Objective

It is debatable whether BCR-ABL1 transcript type has an impact on outcome of treatment of patients with CML, and it is not widely studied whether body weight influences response to treatment. In this study, we tried to find out if any of these factors has an impact on response to treatment and outcome.

Methodology

We conducted a retrospective analysis of the files of 79 patients being treated in our center for CML with known BCR-ABL1 breakpoints, and patients’ management and response assessment was done based on ELN 2013 guidelines. The analysis was performed based on two main groups, obese vs. normal BMI, and then based on BCR-ABL1 transcripts: e13a2 vs. e14a2. Cumulative incidence of MMR, CCyR, and DMR were estimated using the Kaplan–Meier survival curve method, and comparisons between groups were performed by the Log-rank/Gray test methods.

Results/conclusion

In the patient-cohort studied, there was no statistically significant difference in molecular response between patients with CML based on body weight or transcript type although patients in the obesity group achieved higher and faster MMR with no statistical significance.

NAD Modulates DNA Methylation and Cell Differentiation

Nutritional intake impacts the human epigenome by directing epigenetic pathways in normal cell development via as yet unknown molecular mechanisms. Consequently, imbalance in the nutritional intake is able to dysregulate the epigenetic profile and drive cells towards malignant transformation. Here we present a novel epigenetic effect of the essential nutrient, NAD. We demonstrate that impairment of DNMT1 enzymatic activity by NAD-promoted ADP-ribosylation leads to demethylation and transcriptional activation of the CEBPA gene, suggesting the existence of an unknown NAD-controlled region within the locus. In addition to the molecular events, NAD- treated cells exhibit significant morphological and phenotypical changes that correspond to myeloid differentiation. Collectively, these results delineate a novel role for NAD in cell differentiation, and indicate novel nutri-epigenetic strategies to regulate and control gene expression in human cells.

Chronic myelogenous leukemia occurring in two brothers: The opposite sides of the same coin?

Herein we present a rare case of two brothers diagnosed with CML four years apart. Importantly, our case of CML occurrence among siblings is the fifth one reported and the second one investigated by both, conventional cytogenetics and RT-PCR analysis. Moreover, although Ph chromosome was detected in both our patients, RT-PCR revealed the presence of two different BCR-ABL transcripts. Finally, both our patients have been followed for a long period of time offering thus the opportunity to observe the differences in the clinical course.

Two Cases of Possible Familial Chronic Myeloid Leukemia in a Family with Extensive History of Cancer

CML is defined by the presence of an oncogenic fusion protein caused by a reciprocal translocation between chromosomes 9q and 22q. While our molecular understanding of CML pathogenesis has revolutionized drug development for this disease, we have yet to identify many predisposing factors for CML. Familial occurrence of CML has been rarely reported. Here, we describe 2 cases of CML in a 24-year-old woman and in her 73-year-old maternal great aunt. We describe genetic variants in these patients and report on their environmental exposures that may have contributed to CML pathogenesis. The possible familial association of these 2 cases of CML warrants further investigation into more definitive etiologies of this disease.

Epidemiology of the classical myeloproliferative neoplasms: The four corners of an expansive and complex map

The classical myeloproliferative neoplasms (MPNs), specifically chronic myeloid leukemia (CML), polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF), represent clonal myeloid disorders whose pathogenesis is driven by well-defined molecular abnormalities. In this comprehensive review, we summarize the epidemiological literature and present our own analysis of the most recent the Surveillance, Epidemiology, and End Results (SEER) program data through 2016. Older age and male gender are known risk factors for MPNs, but the potential etiological role of other variables is less established. The incidences of CML, PV, and ET are relatively similar at 1.0-2.0 per 100,000 person-years in the United States, while PMF is rarer with an incidence of 0.3 per 100,000 person-years. The availability of tyrosine kinase inhibitor therapy has dramatically improved CML patient outcomes and yield a life expectancy similar to the general population. Patients with PV or ET have better survival than PMF patients.

Response and Resistance to BCR-ABL1-Targeted Therapies

Chronic myeloid leukemia (CML), caused by constitutively active BCR-ABL1 fusion tyrosine kinase, has served as a paradigm for successful application of molecularly targeted cancer therapy. The development of the tyrosine kinase inhibitor (TKI) imatinib allows patients with CML to experience near-normal life expectancy. Specific point mutations that decrease drug binding affinity can produce TKI resistance, and second- and third-generation TKIs largely mitigate this problem. Some patients develop TKI resistance without known resistance mutations, with significant heterogeneity in the underlying mechanism, but this is relatively uncommon, with the majority of patients with chronic phase CML achieving long-term disease control. In contrast, responses to TKI treatment are short lived in advanced phases of the disease or in BCR-ABL1-positive acute lymphoblastic leukemia, with relapse driven by both BCR-ABL1 kinase-dependent and -independent mechanisms. Additionally, the frontline CML treatment with second-generation TKIs produces deeper molecular responses, driving disease burden below the detection limit for a greater number of patients. For patients with deep molecular responses, up to half have been able to discontinue therapy. Current efforts are focused on identifying therapeutic strategies to drive deeper molecular responses, enabling more patients to attempt TKI discontinuation.

Physical Activity, Sitting Time, and Risk of Myelodysplastic Syndromes, Acute Myeloid Leukemia, and Other Myeloid Malignancies

INTRODUCTION

There is limited research on associations of moderate-to-vigorous physical activity (MVPA) and sitting with risk of myeloid neoplasms (MN) or MN subtypes. We examined these associations in the Cancer Prevention Study-II Nutrition Cohort.

METHODS

Among 109,030 cancer-free participants (mean age 69.2, SD 6.1 years) in 1999, 409 were identified as having been diagnosed with a MN [n = 155 acute myeloid leukemia (AML), n = 154 myelodysplastic syndromes (MDS), n = 100 other ML] through June 2013. Cox proportional hazards regression was used to calculate multivariable adjusted hazard ratios (HR) and 95% confidence intervals (CI) for associations of MVPA (MET-h/wk) and sitting (h/d) with risk of all MN, myeloid leukemia only, MDS, and AML.

RESULTS

Compared with insufficient MVPA [>0-<7.5 metabolic equivalent hours/week (MET)-h/wk], the HR (95% CI) for meeting physical activity guidelines (7.5-<15 MET-h/wk MVPA) and risk of MN was 0.74 (95% CI, 0.56-0.98) and for doubling guidelines (15-<22.5 MET-h/wk) was 0.75 (0.53-1.07); however, there was no statistically significant association for higher MVPA (22.5+ MET-h/wk, HR, 0.93; 95% CI, 0.73-1.20). Similarly, meeting/doubling guidelines was associated with lower risk of MDS (HR, 0.57; 95% CI, 0.35-0.92/HR, 0.51; 95% CI, 0.27-0.98), but there was no association for 22.5+ MET-h/wk (HR, 0.93; 95% CI, 0.63-1.37). MVPA was not associated with risk of myeloid leukemia or AML. Sitting time was not associated with risk of any outcome.

CONCLUSIONS

These results suggest that there may be a nonlinear association between MVPA and risk of MDS and possibly other MN.

IMPACT

Further studies are needed to better understand the dose-response relationships between MVPA and risk of MDS, a highly fatal and understudied cancer.

The 5'-AMP-Activated Protein Kinase Regulates the Function and Expression of Human Organic Anion Transporting Polypeptide 1A2

The organic anion transporting polypeptides (OATPs) are important membrane proteins that mediate the cellular uptake of drugs and endogenous substances. OATP1A2 is widely distributed in many human tissues that are targeted in drug therapy; defective OATP1A2 leads to altered drug disposition influencing therapeutic outcomes. 5'-AMP-activated protein kinase (AMPK) signaling plays an important role in the pathogenesis of the metabolic syndrome characterized by an increased incidence of type II diabetes and nonalcoholic fatty liver disease. This study investigated the regulatory role of AMPK in OATP1A2 transport function and expression. We found that the treatment of AMPK-specific inhibitor compound C (dorsomorphin dihydrochloride) decreased OATP1A2-mediated uptake of estrone-3-sulfate in a concentration- and time-dependent manner. The impaired OATP1A2 function was associated with a reduced Vmax [154.6 ± 17.9 pmol × (μg × 4 minutes)-1 in compound C-treated cells vs. 413.6 ± 52.5 pmol × (μg × 4 minutes)-1 in controls]; the Km was unchanged. The cell-surface expression of OATP1A2 was decreased by compound C treatment, but total cellular expression was unchanged. The impaired cell-surface expression of OATP1A2 was associated with accelerated internalization and impaired targeting/recycling. Silencing of the AMPK α1-subunit using specific small interfering RNA corroborated the findings with compound C and revealed a role for AMPK in regulating OATP1A2 protein stability. Overall, this study implicated AMPK in the regulation of the function and expression of OATP1A2, which potentially impacts on the disposition of OATP1A2 drug substrates that may be used to treat patients with the metabolic syndrome and other diseases.

Review of refractory ceramic fiber (RCF) toxicity, epidemiology and occupational exposure

This literature review on refractory ceramic fibers (RCF) summarizes relevant information on manufacturing, processing, applications, occupational exposure, toxicology and epidemiology studies. Rodent toxicology studies conducted in the 1980s showed that RCF caused fibrosis, lung cancer and mesothelioma. Interpretation of these studies was difficult for various reasons (e.g. overload in chronic inhalation bioassays), but spurred the development of a comprehensive product stewardship program under EPA and later OSHA oversight. Epidemiology studies (both morbidity and mortality) were undertaken to learn more about possible health effects resulting from occupational exposure. No chronic animal bioassay studies on RCF have been conducted since the 1980s. The results of the ongoing epidemiology studies confirm that occupational exposure to RCF is associated with the development of pleural plaques and minor decrements in lung function, but no interstitial fibrosis or incremental lung cancer. Evidence supporting a finding that urinary tumors are associated with RCF exposure remains, but is weaker. One reported, but unconfirmed, mesothelioma was found in an individual with prior occupational asbestos exposure. An elevated SMR for leukemia was found, but was absent in the highly exposed group and has not been observed in studies of other mineral fibers. The industry will continue the product stewardship program including the mortality study.

The Cancer Drug Dasatinib Increases PGC-1α in Adipose Tissue but Has Adverse Effects on Glucose Tolerance in Obese Mice

Dasatinib (Sprycel) is a tyrosine kinase inhibitor approved for treatment of chronic myeloid leukemia. In this study, we identify dasatinib as a potent inducer of Peroxisome proliferator-activated receptor gamma coactivator (PGC)-1α mRNA. Dasatinib increased PGC-1α mRNA expression up to 6-fold in 3T3-F442A adipocytes, primary adipocytes, and epididymal white adipose tissue from lean and diet-induced obese mice. Importantly, gene expression translated into increased PGC-1α protein content analyzed in melanoma cells and isolated mitochondria from adipocytes. However, dasatinib treatment had adverse effect on glucose tolerance in diet-induced obese and Ob/Ob mice. This correlated with increased hepatic PGC-1α expression and the gluconeogenesis genes phosphoenolpyruvate carboxykinase and glucose-6-phosphatase. In conclusion, we show that dasatinib is a potent inducer of PGC-1α mRNA and protein in adipose tissue. However, despite beneficial effects of increased PGC-1α content in adipose tissue, dasatinib significantly impaired glucose tolerance in obese but not lean mice. As far as we are aware, this is the first study to show that dasatinib regulates PGC-1α and causes glucose intolerance in obese mice. This should be considered in the treatment of chronic myeloid leukemia.

Obesity over the life course and risk of acute myeloid leukemia and myelodysplastic syndromes

BACKGROUND

Overweight and obesity are known risk factors for a number of cancers, with recent evidence suggesting that risk of hematologic cancer is also increased in obese individuals. We evaluated associations between body mass index (BMI) at differing time points during the life course in population-based case control studies of acute myeloid leukemia (AML) and myelodysplatic syndromes (MDS).

METHODS

Cases were identified by the Minnesota Cancer Surveillance System. Controls were identified through the Minnesota State driver's license/identification card list. BMI was calculated using self-reported height and weight at ages 18, 35, and 50 years and two years prior to interview, and categorized as normal (18.5-25 kg/m(2)), overweight (25-29.9 kg/m(2)), obese class I (30-34.9 kg/m(2)), and obese class II/III (35+ kg/m(2)). All analyses were stratified by sex. Unconditional logistic regression was used to calculate odds ratios and 95% confidence intervals.

RESULTS

We included 420 AML cases, 265 MDS cases and 1388 controls. Obesity two years prior to diagnosis was associated with AML in both males and females (OR=2.22, 95% CI 1.28, 3.85 and OR=1.85, 95% CI 1.08, 3.15 for BMI≥35 vs. BMI 18.5-24.9, respectively). In contrast, associations between obesity and MDS were observed only in females. Weight change in adulthood was not consistently associated with either outcome.

CONCLUSION

Our results extend the emerging literature suggesting that obesity is a risk factor for hematologic malignancy and provide evidence that that the association remains regardless of timing of obesity. Obesity in adulthood is a modifiable risk factor for both MDS and AML.

Role of leptin and leptin receptors in hematological malignancies

Leptin is an adipose-derived cytokine that has an important role in bodyweight homeostasis and energy balance. There are a number of studies which have suggested that leptin and its receptors dysregulation play a critical role in the development of malignancies including hematological malignancies, mainly via activation of the JAK/STAT pathway which regulates downstream signaling pathways such as PI3K/AKT signaling and ERK1/2. In this review, current understandings of leptin/leptin receptors mediated pathogenesis in various lymphoid malignancies are described. Blocking of the leptin receptor might be a unique therapeutic approach for many hematological malignancies.

Phase distribution of chronic myeloid leukemia in Bangladesh

Background

Here, we report the phase distribution of chronic myeloid leukemia (CML), defined based on the World Health Organization criteria, among 63 patients in Bangladesh. All patients were diagnosed based on complete blood count, bone marrow examination including bone marrow aspiration and reverse-transcriptase polymerase chain reaction (RT-PCR). Out of 63 patients, 42 were male and 21 were female. The mean age of the subjects was 37.4 years, with an age range of 17-60 years. The majority of patients (86%) were classified in the chronic phase (CP), 7 (11%) in the accelerated phase (AP) and two (3%) in blast crisis (BC). The most frequent patient age ranges were 21-30 years for CP, 41-50 years for AP and 41-50 years for BC.

Results

The Philadelphia chromosome was detected in 48 patients by RT-PCR. The mean total leukocyte counts, platelet counts, hemoglobin levels and marrow blast frequencies were 101 × 10⁹/L, 409 × 10⁹/L, 12.2 g/dl and 2.8% for CP; 121 × 10⁹/L, 418 × 10⁹/L, 8.7 g/dl and 15% for AP and 311 × 10⁹/L, 396 × 10⁹/L, 9.2 g/dl and 26% for BC, respectively.

Conclusion

This study concluded that most CML patients in Bangladesh are from a younger age group (31-40 years). In addition, males were more commonly affected, although females were afflicted with this disease at a younger age.

Lifestyle and dietary factors in relation to risk of chronic myeloid leukemia in the NIH-AARP Diet and Health Study

BACKGROUND

Aside from exposure to ionizing radiation and benzene, little is known about lifestyle risk factors for chronic myeloid leukemia (CML) in the general population.

METHODS

We examined the relation between lifestyle and dietary risk factors for CML in 493,188 participants (294,271 males and 198,917 females) aged 50 to 71 years who completed a baseline questionnaire in the National Institutes of Health-AARP Diet and Health Study in 1995 to 1996. Over a median of 10.5 years of follow-up, 178 incident cases of CML (139 males and 39 females) were ascertained from state registries. We used Cox proportional hazards models to estimate hazard ratios and 95% confidence intervals for exposures of interest, adjusting for potential confounding variables.

RESULTS

In multivariable analysis of all participants combined, female sex, years of education, and vigorous physical activity (HR for ≥3 times/week vs. <1 time/week 0.70; 95% CI, 0.49-0.99) were inversely associated with risk of CML, whereas smoking intensity (HR for smokers of ≥20 cigarettes per day vs. never smokers: 1.53; 95% CI, 1.03-2.27) and body mass (HR for BMI ≥ 30 vs. <25 kg/m(2) 1.46; 95% CI, 0.95-2.23) were associated with increased risk. A range of dietary factors was not associated with disease.

CONCLUSIONS

This study adds to the sparse information about lifestyle factors, which affect the risk of CML in the general population.

IMPACT

If these findings are confirmed, it would suggest that CML may be amenable to preventive strategies.

Changing trends of chronic myeloid leukemia in greater Mumbai, India over a period of 30 years

Background:

Little is known about burden of chronic myeloid leukemia (CML) in India. There is a recent interest to observe incidence and mortality because of advent of new diagnostic and treatment policies for CML.

Materials and Methods:

We extracted data from the oldest population-based cancer registry of Mumbai for 30 years period from 1976−2005 to observe incidence and mortality rates of CML. We classified the data into four age groups 0–14, 15–29, 30–54 and 55–74 to observe incidence rates in the respective age groups.

Results:

The age specific rates were highest for the age group of 55–74 years. No significant change in trends of CML was observed for 30 years period. However, there was a significant reduction in incidence rate for recent 15-years period (Estimated average annual percentage change=-3.9). No significant reduction in mortality rate was observed till 2005.

Conclusion:

The study demonstrates that age-specific rates for CML are highest in age group of 55-74 years, although they are lower compared to western populations. Significant reduction in incidence of CML in recent periods might be because of reduced misclassification of leukemias. The data of CML has to be observed for another decade to witness reduction in mortality because of changes in treatment management.

Decreasing trend in mortality of chronic myelogenous leukemia patients after introduction of imatinib in Japan and the U.S

PURPOSE

Although the impact of imatinib in improving survival outcomes in chronic myelogenous leukemia (CML) patients has been widely reported, its impact on mortality from CML has not been evaluated. A survival benefit demonstrated in clinical trials does not simply translate to a decrease in mortality. To evaluate the impact of imatinib on the public health, we estimated the age-standardized mortality rate of CML patients in Japan and the U.S. using vital statistics data for Japan and data from the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute for the U.S.

PATIENTS AND METHODS

The period covered in this analysis is 1993-2008, during which 64,203 patients in Japan and 26,888 patients in nine registries in the U.S. died as a result of CML. We used joinpoint regression analysis to evaluate the significance of trends in mortality.

RESULTS

Estimated age-standardized mortality rates decreased significantly in both countries after the availability of imatinib. The annual percent changes (95% confidence interval) in the U.S. were -12.3% (-14.8% to -9.7%) for men and -11.6% (-13.1% to -10.1%) for women. In Japan, these were -20.8% (-36.2% to -1.6%) for men and -15.6% (-18.8% to -12.2%) for women. The period of change in the mortality trend seems to correlate with the period in which imatinib appeared in the two countries. The CML mortality rate in 2008 was nearly 30% that of the 1993 level.

CONCLUSION

This is one example of the advent of a single new drug changing the picture of a single disease, CML. These results may encourage further development of drugs based on the concept of molecular targeting.

The role of adiponectin in cancer: a review of current evidence

Excess body weight is associated not only with an increased risk of type 2 diabetes and cardiovascular disease (CVD) but also with various types of malignancies. Adiponectin, the most abundant protein secreted by adipose tissue, exhibits insulin-sensitizing, antiinflammatory, antiatherogenic, proapoptotic, and antiproliferative properties. Circulating adiponectin levels, which are determined predominantly by genetic factors, diet, physical activity, and abdominal adiposity, are decreased in patients with diabetes, CVD, and several obesity-associated cancers. Also, adiponectin levels are inversely associated with the risk of developing diabetes, CVD, and several malignancies later in life. Many cancer cell lines express adiponectin receptors, and adiponectin in vitro limits cell proliferation and induces apoptosis. Recent in vitro studies demonstrate the antiangiogenic and tumor growth-limiting properties of adiponectin. Studies in both animals and humans have investigated adiponectin and adiponectin receptor regulation and expression in several cancers. Current evidence supports a role of adiponectin as a novel risk factor and potential diagnostic and prognostic biomarker in cancer. In addition, either adiponectin per se or medications that increase adiponectin levels or up-regulate signaling pathways downstream of adiponectin may prove to be useful anticancer agents. This review presents the role of adiponectin in carcinogenesis and cancer progression and examines the pathophysiological mechanisms that underlie the association between adiponectin and malignancy in the context of a dysfunctional adipose tissue in obesity. Understanding of these mechanisms may be important for the development of preventive and therapeutic strategies against obesity-associated malignancies.

Study on the cytogenetic changes induced by benzene and hydroquinone in human lymphocytes

Benzene (BN) is a prototypical hematotoxicant, genotoxic carcinogen, and ubiquitous environmental pollutant. Although the molecular mechanisms of BN-induced cytotoxicity and genotoxic damage are poorly understood in humans, previous studies suggested that bioactivated BN metabolites are capable of oxidative stress, cell cycle arrest, apoptosis, and DNA damage. The objective of the current study was to investigate the BN-induced cytogenetic changes and underlying mechanisms based on these hypotheses. Peripheral blood lymphocytes (PBLs) might be the targets for BN-induced cytotoxicity and genotoxicity, and therefore DNA damage responses of PBLs after exposure to different concentrations of BN (0.25, 3.5, 50 μmol/L) or BN metabolite, hydroquinone (HQ; 50, 150, 450 μmol/L) were studied in vitro. Microculture tetrazolium assay, flow cytometry, 2′,7′-dichlorodihydrofluorescein-diacetate assay, comet assay, micronuclei assay, and attenuated total reflectance microspectroscope were chosen for this study. Based on the results, we reached the conclusion that different concentrations of BN or HQ significantly inhibited cell growth, induced the arrest of S phase and G2/M phase, and increased late apoptosis in a concentration-dependent manner. Furthermore, evidence was also provided to support the conclusion that BN and HQ induced DNA strand breaks and chromosomal mutations in PBL, which indicated the genotoxicity of BN and HQ. Current evidence has indicated that multiple mechanisms including dysfunction of cell cycle, programmed cell death, oxidative stress, and DNA lesions are likely to contribute to BN-induced cytogenetic changes.

Variations in glutathione-S-transferase genes influence risk of chronic myeloid leukemia

Glutathione S-transferases (GSTs) are phase II enzymes that detoxify hazardous xenobiotics including carcinogens. Inter-individual variations in GSTM1 and GSTT1 loci have been associated with several types of cancer, including leukemias. In this study, we investigated the possible association between GSTM1 and GSTT1 polymorphisms and susceptibility to chronic myeloid leukemia (CML) in a Turkish population. In a case-control study, 106 CML patients and 190 healthy controls were evaluated for GSTM1 and GSTT1 polymorphisms. GSTM1 null (GSTM1(-)) genotype frequencies in CML cases and controls were 45.3% and 42.6%, respectively. GSTT1 null (GSTT1(-)) genotype frequencies were 44.3% and 18.4%, respectively. The frequency of the GSTT1(-) genotype among CML patients was significantly higher than in controls [odds ratio (OR) 3.53, 95% confidence interval (CI) 2.08-6.00; P < 0.0001]. Individuals with the GSTM1(-) genotype did not have increased risk of CML [OR: 1.11; 95% CI: 0.69-1.80; P = 0.714]. The combined GSTM1(-)/GSTT1(-) genotype was significantly associated with risk of CML compared to the GSTM1(+) /GSTT1(+) genotype which was most frequent in both cases and controls [OR: 9.47; 95% CI: 3.61-24.87]. Similar findings have only been obtained in Turkish and Indian populations but not elsewhere. The GSTM1(+) /GSTT1(-) genotype was associated with a 2.5-fold increased risk compared with the GSTM1(-)/GSTT1(+) genotype, the second most frequent genotype (OR; 2.46; 95% CI: 1.17, 5.20), suggesting a complex interaction between GSTM1 and GSTT1. Our results indicate an association between the GSTT1(-) genotype, either alone or in combination with GSTM1(-) genotype, and risk of CML, suggesting a possible interaction between GSTM1 and GSTT1. These findings, which are possibly restricted to Turkey and India, warrant further research.

Leptin reverts pro-apoptotic and antiproliferative effects of α-linolenic acids in BCR-ABL positive leukemic cells: involvement of PI3K pathway

It is suspected that bone marrow (BM) microenvironmental factors may influence the evolution of chronic myeloid leukaemia (CML). In this study, we postulated that adipocytes and lipids could be involved in the progression of CML. To test this hypothesis, adipocytes were co-cultured with two BCR-ABL positive cell lines (PCMDS and K562). T cell (Jurkat) and stroma cell (HS-5) lines were used as controls. In the second set of experiments, leukemic cell lines were treated with stearic, oleic, linoleic or α-linolenic acids in presence or absence of leptin. Survival, proliferation, leptin production, OB-R isoforms (OB-Ra and OB-Rb), phosphoinositide 3-kinase (PI3k) and BCL-2 expression have been tested after 24h, 48h and 72h of treatment. Our results showed that adipocytes induced a decrease of CML proliferation and an increase in lipid accumulation in leukemic cells. In addition, CML cell lines induced adipocytes cell death. Chromatography analysis showed that BM microenvironment cells were full of saturated (SFA) and monounsaturated (MUFA) fatty acids, fatty acids that protect tumor cells against external agents. Stearic acid increased Bcl-2 expression in PCMDS, whereas oleic and linoleic acids had no effects. In contrast, α-linolenic acid decreased the proliferation and the survival of CML cell lines as well as BCL-2 and OB-R expression. The effect of α-linolenic acids seemed to be due to PI3K pathway and Bcl-2 inhibition. Leptin production was detected in the co-culture medium. In the presence of leptin, the effect of α-linolenic acid on proliferation, survival, OB-R and BCl-2 expression was reduced.

Obesity and the risk for a hematological malignancy: leukemia, lymphoma, or myeloma

Studies on obesity and the risk for hematological malignancies are reviewed. The paper includes a discussion of the metabolic effects of obesity and their possible role in linking increased body fat to neoplasia.

The aggregate of epidemiological studies indicates a significantly elevated risk for cancer in people with a high body mass index (BMI); a “dose–response” effect exists with increasing risk as BMI increases from the normal to overweight to obese categories. Successful sustained weight loss decreases future risk. The relationship of being overweight to the risk for leukemia in the aggregate has been supported in several large cohort studies and two meta-analyses of cohort and case–control studies. One meta-analysis found an elevated risk for each of the four major subtypes of leukemia. A significant association between the risk for non-Hodgkin's lymphoma and elevated BMI was supported by a meta-analysis of 13 cohort and nine case–control studies. The risk for diffuse large B-cell lymphoma may be especially significant. A high BMI increases the risk for myeloma, as judged by a meta-analysis of 11 cohort and four case–control studies. The biological relationship of obesity to the risk for cancer (biological plausibility) is unresolved. The two major causal final pathways could be “inductive” or “selective.” The metabolic, endocrinologic, immunologic, and inflammatory-like changes resulting from obesity may increase the cell mutation rate, dysregulate gene function, disturb DNA repair, or induce epigenetic changes, favoring the induction of neoplastic transformation (inductive). Alternatively, obesity may create an environment in which pre-existing clones that are dormant are permitted (selected) to emerge.

A novel nanoparticle drug delivery system: the anti-inflammatory activity of curcumin is enhanced when encapsulated in exosomes

Monocyte-derived myeloid cells play vital roles in inflammation-related autoimmune/inflammatory diseases and cancers. Here, we report that exosomes can deliver anti-inflammatory agents, such as curcumin, to activated myeloid cells in vivo. This technology provides a means for anti-inflammatory drugs, such as curcumin, to target the inflammatory cells as well as to overcome unwanted off-target effects that limit their utility. Using exosomes as a delivery vehicle, we provide evidence that curcumin delivered by exosomes is more stable and more highly concentrated in the blood. We show that the target specificity is determined by exosomes, and the improvement of curcumin activity is achieved by directing curcumin to inflammatory cells associated with therapeutic, but not toxic, effects. Furthermore, we validate the therapeutic relevance of this technique in a lipopolysaccharide (LPS)-induced septic shock mouse model. We further show that exosomes, but not lipid alone, are required for the enhanced anti-inflammatory activity of curcumin. The specificity of using exosomes as a drug carrier creates opportunities for treatments of many inflammation-related diseases without significant side effects due to innocent bystander or off-target effects.