Karen F. Santos

Measurement of oxidative stress and antioxidant status in acute lymphoblastic leukemia patients

OBJECTIVES To evaluate the oxidative status and antioxidant defense in patients with acute lymphoblastic leukemia (ALL). DESIGN AND METHODS We measured concentrations of plasmatic thiobarbituric acid reactive substances (TBARS), serum protein carbonylation, whole blood catalase (CAT) and superoxide dismutase (SOD) activities, as well as the plasmatic and erythrocyte thiol levels and serum vitamin E concentration. This study was performed on 80 children with ALL divided into 4 groups: just diagnosed, remission induction, remission maintenance and out-of-treatment. RESULTS TBARS levels and serum protein carbonylation were higher in ALL patients than in controls and reduced levels of antioxidants were found in these patients. CONCLUSION These findings may indicate a possible link between decreased antioxidants and increased levels of cells alterations due to oxidative damage, supporting the idea that there is a persistence of oxidative stress in acute lymphoblastic leukemia.

Changes in acetylcholinesterase (AchE) activity in lymphocytes and whole blood in acute lymphoblastic leukemia patients

BACKGROUND Acute lymphoblastic leukemia (ALL) is a type of cancer that affects lymphocytes and it is the most common form of cancer in children. Acetylcholinesterase (AChE) is well known as having non-cholinergic functions and has been detected in the blood and plasma of humans including in lymphocytes. Thus, we investigated whole blood and lymphocyte AChE activity in patients with ALL. METHODS This study was performed on 72 children with ALL divided into 4 groups: newly diagnosed, remission induction, remission maintenance and out-of-treatment and one control group of 50 healthy subjects. We determined AChE activity in whole blood and lymphocytes of these patients. RESULTS Results demonstrated that whole blood AChE activity was enhanced in the newly diagnosed group and reduced in the remission induction and remission maintenance groups in relation to the control group. For lymphocyte AChE activity we found an increase in the newly diagnosed group and a decrease in the remission induction group in relation to the control. CONCLUSIONS These results suggest that AChE activity was altered in ALL patients. This fact may be related with the essential role played by AChE in the development of hematological disease and its contribution to the regulation of immune function.

Cholinesterase activities and biochemical determinations in patients with prostate cancer: Influence of Gleason score, treatment and bone metastasis

Prostate cancer (PCa) is the sixth most common type of cancer worldwide. Cholinesterase is well known as having non-cholinergic functions such as cellular proliferation and differentiation, suggesting a possible influence of cholinesterase in tumorogenesis. Thus, the aim of this study was to investigate the whole blood acetylcholinesterase (AChE) and plasma butyrylcholinesterase (BChE) activities and some biochemical parameters in PCa patients. This study was performed in 66 PCa patients and 40 control subjects. AChE and BChE activities were determined in PCa patients and the influence of the Gleason score; bone metastasis and treatment in the enzyme activities were also verified. Furthermore, we also analyzed possible biochemical alterations in these patients. AChE and BChE activities decreased in PCa patients in relation to the control group and various biochemical changes were observed in these patients. Moreover, Gleason score, metastasis and treatment influenced cholinesterase activities and biochemical determinations. Our results suggest that cholinesterases activities and biochemical parameters are altered in PCa. These facts support the idea that the drop in the cholinesterase activity and the consequent increased amount of acetylcholine could lead to a cholinergic overstimulation and increase the cell proliferation in PCa.

Ectonucleotide pyrophosphatase/phosphodiesterase (E-NPP) and adenosine deaminase (ADA) activities in prostate cancer patients: influence of Gleason score, treatment and bone metastasis.

The relation between adenine nucleotides and cancer has already been described in literature. Considering that the enzymes ectonucleotide pyrophosphatase/phosphodiesterase (E-NPP) and adenosine deaminase (ADA) act together to control nucleotide levels, we aimed to investigate the role of these enzymes in prostate cancer (PCa). E-NPP and ADA activities were determined in serum and platelets of PCa patients and controls. We also verified the influence of the Gleason score, bone metastasis and treatment in the enzyme activities. Platelets and serum E-NPP activity increased, whereas ADA activity in serum decreased in PCa patients. In addition, Gleason score, metastasis and treatment influenced E-NPP and ADA activities. We may propose that E-NPP and ADA are involved in the development of PCa. Moreover, E-NPP and ADA activities are modified in PCa patients with distinct Gleason score, with bone metastasis, as well as in patients under treatment.