Search

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., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Introduction: Cervical cancer remains the second leading cause of death among women. Intraepithelial neoplasias and uterine invasive cancer are frequently associated with disturbances in coagulation and changes in the concentrations of adenine nucleotides. This work intended to analyze changes in extracellular adenine nucleotide hydrolysis and blood platelet aggregation in patients diagnosed for cervical intraepithelial neoplasia in different stages as well as uterine invasive cancer., Patients and Methods: NTPDase, E-NPP, 5'-nucleotidase, total ADA and its isoforms (ADA1 and ADA2), as well as the platelet aggregation from patients with different stages of cervical intraepithelial neoplasia (NICs I, NIC II, NIC III) and uterine invasive cancer were verified., Results: Neither ATP hydrolysis nor E-NPP activity was changed by the neoplasia stage. On the other hand, ADP and AMP hydrolysis as well as ADA activity were enhanced in NIC I group. AMP hydrolysis was also increased in the cancer group. ADA 1 was the ADA isoform found in platelets from both control and patient groups., Conclusion: Our results showed for the first time that NTPDase, 5'-nucleotidase, E-NPP and ADA are not sensible regarding the grade of neoplasia development, since no significant difference was found between the groups studied. Only ADP hydrolysis and ADA activity showed a significant enhancement in NIC I group related to the other stages possibly as a result of the beginning of the neoplasic transformation. This increase could be reflecting a body's reaction against the probable high adenosine levels. We propose for the first time that the ADA isoform present in platelets is ADA 1., (© 2012 Elsevier Masson SAS. All rights reserved.)

Background: The nucleotides and nucleosides of adenine are signaling molecules related to thromboregulation and modulation of immune responses in patients with malignancies. Thus, this study aims to determine NTPDase, 5'-nucleotidase, ectonucleotide pyrophosphatase/phosphodiesterase (E-NPP) and adenosine deaminase (ADA) activities in the platelets of patients with lung cancer., Methods: We collected blood samples from patients (n=33) previously treated for lung cancer with chemotherapy. Patients were classified as stage IIIb and IV according to the Union for International Cancer Control (UICC)., Results: Patients showed a significant decrease in the hydrolysis of adenosine diphosphate (ADP) and adenosine, whereas the adenosine monophosphate (AMP) hydrolysis and platelet aggregation were significantly increased in this group. Adenosine triphosphate (ATP) hydrolysis did not show significant results between the group of patients and the control group., Conclusions: We may suggest that ectonucleotidases as well as ADA are enzymes involved in thromboembolic events but especially here we may see that they are also directly involved in the generation of adenosine formation in the cancer patient circulation., (© 2011 Elsevier Masson SAS. All rights reserved.)

Background: Uterine cervical neoplasia is an important worldwide malignancy sometimes associated with thrombosis. Ectonucleotidases are membrane-bound enzymes which participate in thromboregulation by hydrolyzing adenine nucleotides in the extracellular medium. In this sense, we aimed to investigate their activity in patients with uterine cervical neoplasia., Methods: We evaluated NTPDase and 5'-nucleotidase activities from patients previously treated for uterine cervical neoplasia with either conization or radiotherapy (RTX). These patients were divided into four groups: two conization groups (I and II) and two RTX groups (III and IV), which were further divided based on the amount of time that had passed since the conclusion of their treatment, where groups I and III were extended-remission-period groups (patients with 1 to 5 years elapsed after the conclusion of treatment), and groups II and IV were recently treated patients (treated up to three months before)., Results: For both conization and RTX groups, ATP and ADP hydrolysis decreased in the extended-remission groups when compared to the control and recently treated groups. On the other hand, AMP hydrolysis was decreased in all the treated groups (both conization and RTX) compared to the control. CD39 expression was decreased in extended-remission groups (I and III) when compared to the other groups., Conclusions: NTPDase protects against platelet aggregation and 5'-nucleotidase is more involved in the control of adenosine formation., (2010 Elsevier Masson SAS. All rights reserved.)

In this paper, we studied the influence of uremia and hemodialysis on oxidative parameters and delta-aminolevulinic acid dehydratase (delta-ALA-D) activity in control subjects, patients with chronic renal failure (CRF) on hemodialysis treatment (HD) and in patients not undergoing hemodialysis (ND). An increased lipid peroxidation was observed in the serum of HD and ND patients, as measured by the MDA serum levels. However, the level of MDA from erythrocytes was only elevated in HD patients. Blood catalase activity was increased in HD and ND groups. This study also showed a decreased activity of blood delta-aminolevulinic acid dehydratase (delta-ALA-D) in both groups of patients. This study demonstrated a positive correlation between ALA-D activity and hemoglobin, suggesting that inhibition of this enzyme might enhance anemia in CRF. A negative correlation was found between the alteration in delta-ALA-D activity and oxidative stress, which may indicate that the inhibition of ALA-D can be used as an index of oxidative stress.