[Diurnal rhythm of serum leptin in patients with solid tumors]. / Diurnální rytmus sérového leptinu u pacientu se solidními nádory.

Leptin is a protein produced by fat tissue. It has many regulatory effects in the area of energetic metabolism, immunity and haematopoiesis. Its role in tumour diseases especially in states with cachexia is studied. Its physiological diurnal rhythm is very well known. There is lack of information about diurnal rhythm of leptin in tumour diseases except some endocrine tumours. In this study 10 patients with breast and colorectal cancer without marks of kachexia and mostly without pre-existing chemotherapy were examined. The diurnal rhythm of leptin was preserved in cancer patients (morning minimum 10.5 +/- 4.2 ng/ml and nocturnal maximum 17.9 +/- 10.1 ng/ml). The difference between males and females (p < 0.01) and correlation of concentrations of leptin with BMI (r = 0.61, p < 0.001) were preserved too. Basal concentrations of leptin were not different from values of healthy blood donors (10.2 +/- 4.3 ng/ml). Maybe preservation of diurnal rhythm of leptin can be important in planning of cytostatic and immunomodulatory therapy in future.

[The importance of leptin in oncology--hypothesis or facts?]. / Význam leptinu v onkologii--hypotéza nebo fakta?

Leptin was described as a protein produced mostly by adipocytes which participates in regulation of caloric intake. This protein has further many physiological regulatory functions especially in hematopoesis and reproduction. The role of leptin in diseases is also considered. Maybe leptin is a part of the pathogenic mechanism or its metabolism can be influenced secondary to disease. Malignant tumours are the important area where leptin can acts. This imagination is supported by recent in vitro studies and some clinical observations. It is consider that some parameters of leptin metabolism can serve as usable marker for diagnosis and monitoring of some malignant tumours--especially breast cancer or some types of leukemia. The authors give a review of actual information of leptin metabolism changes in oncological diseases.

Bone marrow and peripheral blood leptin levels in lymphoproliferative diseases--relation to the bone marrow fat and infiltration.

Leptin is a nonglycosylated protein produced mostly by adipocytes. The role ofleptin in body weight regulation through its anorectic effect in hypothalamus is very well known. Less known are other leptin effects such as the stimulation of hematopoesis and some parts of immunity system. The role of leptin in the pathogenesis of some malignant tumors is discussed. Only a little is known about bone marrow adipocyte leptin production. We examined leptin concentrations in the sera from peripheral blood and bone marrow, the percentage of bone marrow fat, the degree of bone marrow infiltration, the body mass index (BMI) in 42 patients with lymphoproliferative diseases. We found that bone marrow has significantly lower leptin levels (6,6+/-10,9 ng/ml) than peripheral blood (9,1+/-11,5 ng/ml) (p < 0.0001). Bone marrow and peripheral blood leptin levels have also a significant thin correlation (r = +0.91, p < 0.0001). Bone marrow (r = +0.55, p < 0.0005) and peripheral blood (r = +0.52, p < 0.0005) leptin concentrations are significantly correlated to BMI. Blood serum leptin (r = +0.46, p < 0.003) and bone marrow leptin (r = +0.40, p < 0.01) are related to the bone marrow fat percentage. In addition we found a negative correlation of blood serum leptin (r = -0.59, p < 0.0001) and bone marrow leptin (r = -0.42, p < 0.005) to bone marrow malignant infiltration. When we divided the patients into groups with bone marrow infiltration more than 10% and without or less than 10% infiltration, the first group had significantly lower peripheral blood (p < 0.001) and bone marrow (p < 0.02) leptin. We also confirmed a relation of bone marrow fat and infiltration (r = +0.49, p < 0.001). Our results suggest a relationship among leptin levels in blood or bone marrow and bone marrow infiltration in lymphoproliferative diseases. This fact needs further investigation and an evaluation of its application in clinical practice.

[Leptin levels in peripheral blood and bone marrow in orthopedic patients]. / Hladiny leptinu v sérech z periferní krve a kostní drene u ortopedických pacientu.

Leptin is a protein with hormonal activity and is produced mainly by adipocytes. Its primary function in the human organism is regulation of the calorie intake via the anorectic action in the hypothalamus. Leptin participates also in the regulation of haematopoiesis and immunity processes. There are many data on leptin production by peripheral adipose tissue and it is also known that leptin is produced by adipocytes of bone marrow. It was assumed for a long time that adipocytes of bone marrow are not only a passive source of energy but have, similarly as stromal cells, a regulatory function. However, it is not clear in what way the adipose tissue of bone marrow participates in the regulation of haematopoiesis and what role is played in this relationship by leptin production. The authors attempted to assemble in their small study data on leptin production in bone marrow and at the same time parameters of lipids of bone marrow which can be assessed by cytological examination. The authors examined 16 patients (9 men and 7 women) subjected to orthopaedic surgery. They assessed leptin concentrations in sera obtained from peripheral blood and bone marrow, and at the same time they assessed by morphological examination in smears of bone marrow some parameters associated with lipids. The authors found that serum leptin levels from bone marrow are significantly lower than in peripheral blood (p < 0.0005). These values correlate closely (r = +0.77, p < 0.0005). The authors found also a positive correlation between serum leptin (r = +0.56, p < 0.02) and bone marrow leptin (r = +0.72, p < 0.002) and the body mass index (BMI). A positive correlation was found also between serum (r = +0.65, p < 0.006) and bone marrow leptin (r = +0.80, p < 0.0002) and age. The authors did not detect any significant correlations between parameters of the lipids of bone marrow and leptin levels in serum and bone marrow. The assembled results can in combination with data from the literature indicate that the actual amount of leptin in bone marrow is influenced rather by its consumption by haematopoietic tissue than by its production.

Pulmonary sarcoidosis in a patient with essential thrombocythemia treated with interferon alpha: a short case report.

A patient with essential thrombocythemia was diagnosed with pulmonary sarcoidosis after interferon alpha therapy. Following interferon treatment the miliary pulmonary dissemination has appeared and after disruption of this therapy it resolved during two months. Few cases of sarcoidosis associated with interferon alpha treatment have been reported. These patients were treated for chronic myelogenous leukemia, chronic hepatitis C, and renal cell carcinoma. We report the first case of interferon-related sarcoidosis in an essential thrombocythemia patient.

Osteoblasts and osteoclasts in bone marrow smears of cancer patients.

Osteoblasts and osteoclasts are the unique cells occurring in bone marrow smears in situations with high bone metabolic turnover (children, trauma, rachitis, Paget disease or tumors). The collection of 2706 sternal or iliac crest aspirates from patients with hematologic malignancies and solid tumors are presented. We demonstrated significantly higher positivity for osteoblasts-osteoclasts presentation in bone marrow smears for hematological malignancies (p < 0.05), solid tumors (p < 0.01), and especially breast cancer (p < 0.001). We found a significant association between osteoblast-osteoclast positivity and dissemination of breast cancer (p < 0.05). None of the breast cancer patients without signs of dissemination (X-ray, sonography or scintigraphy) had positivity for osteoblasts or osteoclasts. We suppose that the osteoblast-osteoclast positivity in bone marrow smears can serve as a cheap marker for breast cancer dissemination.

[Treatment with interferon and autoimmunity]. / Lécba interferonem a autoimunita.

Interferons are commonly used, frequently already as a standard drug, in a relatively wide spectrum of indications in tumourous and non-tumourous diseases. The numerous undesirable therapeutic effects include also relatively frequent induction of autoimmune processes which, however, only rarely is associated with marked clinical manifestations. The author presents an account on two patients from their own clinical practice treated with interferon alpha who developed complications which in the author's opinion may be associated with autoimmunity (a patient with thrombocytopenia responding well to immunosuppressive treatment, originally treated on a chi ount of renal carcinoma, and a female patient with pulmonary sarcoidosis treated for essential thrombocythemia). The authors present also a brief review of the literature on autoimmunity induced by interferon.