leptin and Leukemia

Topics: Adipocytes; Animals; Anorexia; Breast Neoplasms; Cell Differentiation; Female; Gastrointestinal Neoplasms; Genital Neoplasms, Female; Growth Substances; Humans; Leptin; Leukemia; Male; Neoplasms; Prostatic Neoplasms

The receptor for leptin, the gene product of the obese gene, is expressed in hematopoietic stem cells. Leptin stimulates normal myeloid and erythroid development, and is secreted from bone marrow adipocytes, which occupy most of the marrow cavity in humans. Leptin might thus play an important role in the control of the expansion and differentiation of primitive hematopoietic cells through paracrine interaction in the bone marrow microenvironment. Leukemic cells of some patients with acute myeloblastic leukemia, acute lymphoblastic leukemia, and chronic myeloid leukemia (CML) also express the leptin receptor. In cases of CML, higher expression of leptin receptor is observed during blast crisis than in chronic phase. Leptin alone and in combination with other cytokines has stimulative effects on proliferation of leukemia cells as well as anti-apoptotic effects. These findings suggest the possibility that leptin plays roles in the pathophysiology of leukemia.

Topics: Carrier Proteins; Humans; Leptin; Leukemia; Obesity; Receptors, Cell Surface; Receptors, Cytokine; Receptors, Leptin

Genotype/allele distributions of leptin promoter G-2548A polymorphism, serum leptin and insulin levels and body weight were not significantly different between 72 children (39 male/33 female; age range 1.08-16, median 6 years) with acute leukemia (56 acute lymphoblastic leukemia [ALL]/16 acute non-lymphoblastic leukemia [ANLL]) at diagnosis and 70 age- and sex-matched controls (p > 0.05). The - 2548GG genotype was associated with the highest leptin levels in controls and patients with acute leukemia after 7-day high-dose methylprednisolone (HDMP) therapy (p < 0.05), while no significant association of genotype with leptin levels was detected in patients at diagnosis (p > 0.05). One-week HDMP therapy in patients carrying the - 2548G allele caused a significant increase in leptin levels and body weight (p < 0.001), whereas increases in those carrying the - 2548AA genotype were insignificant (p > 0.05). Decreases in white blood cell counts of patients after therapy were insignificant in - 2548GG (p > 0.05) yet significant in - 2548GA and - 2548AA (p < 0.05) genotypes. These results revealed no association of leptin genotype with the etiology of childhood acute leukemia but a possible association with leptin levels and effects of HDMP therapy.

Topics: Acute Disease; Adolescent; Case-Control Studies; Child; Child, Preschool; Diarrhea; Dose-Response Relationship, Drug; Female; Gene Frequency; Genotype; Glucocorticoids; Humans; Hyperglycemia; Infant; Insulin; Leptin; Leukemia; Male; Methylprednisolone; Polymorphism, Single Nucleotide; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Promoter Regions, Genetic; Prospective Studies; Time Factors; Treatment Outcome

Material and methods: a retrospective study of childhood acute leukemia survivors. Survivors with a diagnosis of leukemia before 16 years of age in a tertiary hospital, during the period of 1998-2018, were selected, who had completed their treatment at least two years earlier. We examined: blood adipokine levels and carbohydrate metabolism, body composition by bioimpedance, and carotid status by ultrasound. Somatometric measures were also taken. Results: the registry showed 82 children diagnosed with acute leukemia, aged between 6 and 16 years. Only 22 met the criteria to be included in the study. Results reveled that 32 % of the sample met the criteria for overweight-obesity, and 36 % had high insulin resistance indexes (IR). Leptin levels were higher in women (15.45 vs. 3.25; p = 0.044) and in obese and overweight subjects, as was the leptin/adiponectin ratio, which rises in the presence of IR (2.52 vs. 0.45; p = 0.037). We observed an increase in carotid intima-media thickness in relation to BMI (0.008; CI, -0.002 to 0.013; p = 0.007) without any association with an increase in fat mass in these patients (0.204; CI, -0.043 to 0.451; p = 0.101). Conclusions: childhood leukemia survivors have a high cardiovascular risk, characterized by an increase in IR, not associated with an increase in fat mass. This risk could justify the implementation of preventive actions in these long-lived patients.. Material y métodos: estudio retrospectivo de supervivientes de leucemia aguda en edad infantil. Se seleccionaron aquellos supervivientes con diagnóstico de leucemia antes de los 16 años de edad, en un hospital de tercer nivel y durante el período 1998-2018, que hubieran finalizado su tratamiento como mínimo dos años antes. Se analizaron: niveles de adipokinas y metabolismo hidrocarbonado en sangre, composición corporal mediante bioimpedancia y evaluación ecográfica carotídea. Se tomaron además datos somatométricos. Resultados: de 82 niños con diagnóstico de leucemia aguda, con edades comprendidas entre 6 y 16 años, incluidos en el registro, solamente 22 cumplieron los criterios para ser incluídos en el estudio. Entre los resultados destaca que el 32 % de la muestra cumplían los criterios de sobrepeso-obesidad y el 36 % presentaban índices de resistencia insulínica (RI) elevados. Los niveles de leptina fueron más elevados en las mujeres (15,45 vs. 3,25; p = 0,044) y en los individuos con obesidad o sobrepeso, así como la ratio leptina/adiponectina, que se eleva en presencia de RI (2,52 vs. 0,45; p = 0,037). Se observó un incremento del grosor mediointimal carotídeo en relación con el IMC (0,008; IC: -0,002 a 0,013; p = 0,007) sin asociarse a un aumento de masa grasa en estos pacientes (0,204; IC: -0,043 a 0,451; p = 0,101). Conclusiones: los pacientes supervivientes de leucemia en la edad infantil tienen un riesgo cardiovascular elevado, caracterizado por un aumento de la RI no asociado a aumento de la masa grasa. Este riesgo podría justificar la implementación de medidas preventivas en estos pacientes, cada vez más longevos.

Topics: Adipokines; Adiponectin; Adolescent; Cardiovascular Diseases; Carotid Intima-Media Thickness; Child; Cross-Sectional Studies; Female; Heart Disease Risk Factors; Humans; Insulin Resistance; Leptin; Leukemia; Male; Obesity; Overweight; Retrospective Studies; Risk Factors; Survivors

Mesenchymal stromal cells (MSCs) are a major component of the leukemia bone marrow (BM) microenvironment. Connective tissue growth factor (CTGF) is highly expressed in MSCs, but its role in the BM stroma is unknown. Therefore, we knocked down (KD) CTGF expression in human BM-derived MSCs by CTGF short hairpin RNA. CTGF KD MSCs exhibited fivefold lower proliferation compared with control MSCs and had markedly fewer S-phase cells. CTGF KD MSCs differentiated into adipocytes at a sixfold higher rate than controls in vitro and in vivo. To study the effect of CTGF on engraftment of leukemia cells into BM, an in vivo model of humanized extramedullary BM (EXM-BM) was developed in NOD/SCID/IL-2rg(null) mice. Transplanted Nalm-6 or Molm-13 human leukemia cells engrafted at a threefold higher rate in adipocyte-rich CTGF KD MSC-derived EXM-BM than in control EXM-BM. Leptin was found to be highly expressed in CTGF KD EXM-BM and in BM samples of patients with acute myeloid and acute lymphoblastic leukemia, whereas it was not expressed in normal controls. Given the established role of the leptin receptor in leukemia cells, the data suggest an important role of CTGF in MSC differentiation into adipocytes and of leptin in homing and progression of leukemia.

Topics: Adipocytes; Animals; Bone Marrow; Bone Marrow Cells; Bone Marrow Transplantation; Cell Cycle; Cell Differentiation; Cell Proliferation; Cell Separation; Chemokine CXCL12; Connective Tissue Growth Factor; Down-Regulation; Gene Knockdown Techniques; Humans; Leptin; Leukemia; Leukemia, Myeloid, Acute; Mesenchymal Stem Cells; Mice; Precursor Cell Lymphoblastic Leukemia-Lymphoma

Adiponectin plays a protective role in several malignancies, including myeloblastic leukemia, whereas leptin may increase the proliferation of progenitor cells and may stimulate leukemic cell growth in vitro. We investigated the role of adiponectin and leptin levels in the etiopathogenesis of myelodysplastic syndromes (MDS), a preleukemic condition with increasing incidence which has recently been associated with obesity.. In a case-control study, 101 cases with incident, histologically confirmed primary MDS and 101 controls matched on gender and age were studied between 2004 and 2007, and blood samples were collected.. Higher serum adiponectin levels were associated with lower risk of MDS by bivariate analysis and after adjusting for age, gender, body mass index and serum levels of leptin (p < 0.001). Subjects in the third quartile for leptin levels had a lower risk of MDS than controls, and low leptin concentrations were observed in low-risk MDS patients with normal or good prognostic karyotype after adjusting for age, gender and body mass index.. Circulating adiponectin and leptin may play an important role in MDS etiopathogenesis. Future studies are needed to confirm these associations and to explore underlying mechanisms.

Topics: Adiponectin; Aged; Biomarkers; Biomarkers, Tumor; Case-Control Studies; Female; Humans; Leptin; Leukemia; Male; Middle Aged; Myelodysplastic Syndromes; Obesity; Precancerous Conditions; Predictive Value of Tests; Prognosis

Leptin is an adipocyte-derived hormone regulating energy homeostasis and body weight. Leptin also plays a role in hematopoiesis, cell cycle regulation, and in oncogenesis. The leptin receptor is a single transmembrane protein belonging to the superfamily of cytokine receptors, structurally related to the hemopoietin receptor family. The aim of the study was to evaluate bone marrow and peripheral blood leptin level and frequency of distribution of leptin receptor gene polymorphism Gln223Arg in children with acute leukemia. The examined group included 92 children with acute leukemia (83 ALL and 9 AML) and 39 non-leukemic control children. Leptin level was measured by ELISA method at the day of leukemia diagnosis. Genomic DNA was isolated with the use of a column method and the genotyping of DNA sequence variation was carried out by the restriction enzyme analysis of PCR - amplified DNA. The samples were then electrophoresed on 2.5% agarose gel. Leptin level in leukemic children was lower than in healthy children. Bone marrow leptin level was significantly lower than that in the blood in leukemic children with ALL-T and AML. An analysis of frequency distribution of the Gln233Arg polymorphism in the leptin receptor gene in leukemic children showed lack of differences between the patients and controls. There was no difference in the genotype frequencies between the leukemic AML and ALL groups either. The results indicate a possible relation between the leptin level and leukemia development in children. The effectory effect of the hormone seems not related to Gln223Arg polymorphism of its receptor.

Topics: Adolescent; Bone Marrow; Child; Child, Preschool; Humans; Infant; Leptin; Leukemia; Leukemia, Myeloid, Acute; Polymorphism, Genetic; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Receptors, Leptin

Leptin has important effects on bone metabolism. Possible relationships between leptin and bone mineral density were evaluated in the survivors of the childhood leukemia and lymphoma. Twenty patients were included the study. Anthropometric parameters, growth hormone response to provocative test, serum calcium, phosphorus, alkaline phosphates, osteocalcin, leptin levels, urinary calcium and deoxyypyridinoline levels, and bone mineral density were obtained. Anthropometric parameters of patients were not significantly different from those of a control group. Growth hormone provocative test was abnormal in 3 patients who received cranial radiotherapy. The osteocalcin levels and bone mineral density of patients were significantly lower than in the control group (p=.001, p=.02). Nine patients were in the osteopenic and 7 were in the osteoporotic range. The leptin levels of patients were significantly lower (p=.01) than in the control group. Bone mineral density (BMD) was significantly correlated with leptin level, age, body mass index, and Tanner stage in simple correlation analysis. However, in multivariate analysis only age was significant (p<.000, r: .752). Markers of bone metabolism, BMD, and leptin levels were not related with the growth hormone status of patients and did not present a correlation with the cumulative doses of drugs. There are a few studies evaluating the relationship between BMD and leptin levels in childhood cancer. Although this study did not find any correlation between the leptin level and BMD, detailed studies of larger numbers of patients are necessary to evaluate causes of decreased leptin level and the possible role of leptin on osteopenia observed in survivors of childhood cancer.

Topics: Adolescent; Body Mass Index; Bone and Bones; Bone Density; Bone Diseases, Metabolic; Child; Disease-Free Survival; Female; Humans; Leptin; Leukemia; Lymphoma; Male; Minerals; Osteocalcin

Leptin promotes the growth and viability of hematopoietic cells, and it also stimulates microvessel formation, indicating a role for leptin in angiogenesis. Acute myelocytic leukemia (AML) remains a disease with poor prognosis. Similar to solid tumors, it probably requires angiogenesis to ensure adequate supplies of nutrients. We studied rats with transplanted AML to test if a neutralizing anti-leptin receptor monoclonal antibody (mAb) (anti-OB-R) could inhibit leukemogenesis. At 4 weeks after transplantation, the bone marrow contained about 80% leukemic cells as assayed with a specific mAb and flow cytometry. Microscopic examination of bone marrow sections stained with an anti-von Willebrand mAb revealed a marked increase in microvessel density in the leukemic rats compared with controls. Treatment with anti-OB-R for 3 weeks more than halved the content of bone marrow leukemic cells with a concomitant, substantial decrease in angiogenesis. A parallel experiment using an irrelevant anticasein mAb showed no effect on either leukemic cell growth or angiogenesis. We could not detect surface expression of the leptin receptor on the leukemic cells, but on mononuclear cells from healthy rats. The anti-OB-R did not affect in vitro proliferation of leukemic cells whereas proliferation of the mononuclear cells was markedly impaired. The anti-OB-R had no effect on either leukemic cell growth or angiogenesis in leukemic fa/fa rats with a mutated leptin receptor. We conclude that leptin stimulates leukemic cell growth in vivo by promoting angiogenesis. Inhibition of binding of leptin to its receptor might be a new adjunct therapy in AML.

Topics: Animals; Antibodies, Monoclonal; Bone Marrow Cells; Cell Division; Leptin; Leukemia; Neovascularization, Pathologic; Protein Binding; Rats; Receptors, Cell Surface; Receptors, Leptin; Tumor Cells, Cultured