ABSTRACT
Aim: Leptin is a hormone secreted by adipocytes that regulates body weight and energy expenditure. Leptin receptors can be expressed by acute myelogenous leukemia [AML] cells and leptin may affect leukemic hematopoiesis. In addition, leptin may function as a stress-related hormone and may contribute to the anorexia and wasting syndrome of cancer and infections. The present work aimed at estimating the serum leptin level in patients with AML at presentation and after induction chemotherapy in order to extrapolate its possible alteration with infection in these patients and its role in influencing hematopoietic recovery following chemotherapy. Subjects and Thirteen newly diagnosed AML patients, 7 males and 6 females [mean age: 40.54 +/- 13.5 years] and ten healthy age- and sex-matched controls were enrolled in the study. Serum leptin was estimated by the ELLSA technique. In AML patients, the pretreatment mean serum leptin [15.8 +/- 19.8 ng/ml] did not differ significantly from the controls [8.25 +/- 7.25 ng/ml]. Post-chemotherapy, the mean serum leptin level [12.1 +/- 14 ng/ml] decreased compared to the pre-therapy level. However, this decrease was not statistically significant. A significant positive correlation was found between serum leptin and body mass index [BMI], both at presentation [r=0.777, P=0.002] and post-chemotherapy [r=0.557: P=0.048], and serum leptin was significantly higher in female as compared to male patients before and after chemotherapy [P=0.001 and P=0.024, respectively]. No significant correlation was found between serum leptin and any of the studied parameters [hemoglobin, total leukocytic count, platelet count, bone marrow blast percent, absolute neutrophilic count and days to hematopoietic recovery]. Also, no significant difference was found between patients who achieved complete remission [n=6] and those who achieved partial remission [n=5] regarding the serum leptin both before and after therapy. Comparing the mean serum leptin levels in patients who developed chemotherapy-induced neutropenic sepsis [n=11] and those who did not develop sepsis [n=2], the level was significantly higher in the former than in the latter, both before [P-0.005] and after [P=0.012] chemotherapy. Conclusions: The findings of the present study support the hypothesis that leptin is a stress-related hormone involved in the host defense of acute inflammation and may be important for survival. However, further studies are warranted to clarify the potential diagnostic, prognostic and therapeutic roles of leptin in patients with AML