Early detection of high oxidative activity in patients with adenomatous intestinal polyps and colorectal adenocarcinoma: myeloperoxidase and oxidized low-density lipoprotein in serum as new markers of oxidative stress in colorectal cancer.
OBJECTIVE
To detect whether signs of oxidative stress appear at early stages of colorectal adenocarcinoma (CRC), particularly in the polyp stage. We also aimed to evaluate the specific entities myeloperoxidase (MPO) and oxidized low-density lipoprotein (oxLDL) as novel markers of oxidation in the plasma of patients with CRC and to study the relationship between oxidative status in plasma and patient survival.


METHODS
We assayed serum or plasma specimens from healthy control subjects (n = 14), from patients with intestinal polyps (n = 39), and from patients with CRC (n = 128) to calculate the modified oxidative balance score (MOBS) using several serum markers (β-carotene, lycopene, vitamin A, vitamin E, MPO, and oxLDL). We also assayed the levels of C-reactive protein (CRP) and obtained lipid profiles. Finally, we studied the survival of patients in relationship to oxidative status (antioxidants and pro-oxidants) and inflammation markers, and added theses data to the lipid profile for each patient.


RESULTS
Oxidative stress levels increased as disease stage advanced. This increase was detected early in the polyp stage, before polyps progressed to cancer, and could be measured by the increase of such new markers as MPO and oxLDL, the decrease in antioxidants, and the MOBS value. Higher levels of oxidation correlated with lower survival.


CONCLUSIONS
The oxidation process, which can cause mutations leading to CRC, begins development in the polyp stage. This process may be detected early by monitoring serum markers such as MPO and oxLDL.
Department of Clinical Laboratory, Clinical Hospital, University of Valladolid, Valladolid, Spain pmpeius@hotmail.com.
Jesús
J
Crespo-Sanjuán
Department of Clinical Laboratory, Clinical Hospital, University of Valladolid, Valladolid, Spain.
María D
MD
Calvo-Nieves
Department of Clinical Laboratory, Clinical Hospital, University of Valladolid, Valladolid, Spain.
Beatriz
B
Aguirre-Gervás
Department of Clinical Laboratory, Clinical Hospital, University of Valladolid, Valladolid, Spain.
José
J
Herreros-Rodríguez
Department of Clinical Laboratory, Clinical Hospital, University of Valladolid, Valladolid, Spain.
Benito
B
Velayos-Jiménez
Department of Nutrition, School of Medicine, University of Valladolid, Valladolid, Spain.
María J
MJ
Castro-Alija
Department of Clinical Laboratory, Clinical Hospital, University of Valladolid, Valladolid, Spain.
María F
MF
Muñoz-Moreno
Department of Biochemistry, Molecular Biology, and Physiology, Biology and Genetics Institute, University of Valladolid-Superior Council of Scientific Investigations (CSIC), Valladolid, Spain.
Diego
D
Sánchez
Department of Clinical Laboratory, Clinical Hospital, University of Valladolid, Valladolid, Spain.
Nuria
N
Zamora-González
Department of Biochemistry, Molecular Biology, and Physiology, Biology and Genetics Institute, University of Valladolid-Superior Council of Scientific Investigations (CSIC), Valladolid, Spain.
Raquel
R
Bajo-Grañeras
Department of Clinical Laboratory, Clinical Hospital, University of Valladolid, Valladolid, Spain.
Rosa M
RM
García-Centeno
Department of Clinical Laboratory, Clinical Hospital, University of Valladolid, Valladolid, Spain.
María E
ME
Largo Cabrerizo
Department of Clinical Laboratory, Clinical Hospital, University of Valladolid, Valladolid, Spain.
María R
MR
Bustamante
Río Hortega University Hospital, Valladolid, Spain.
José A
JA
Garrote-Adrados
D011125:Adenomatous Polyposis Coli / Q000097:blood* / Q000175:diagnosis*; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D002097:C-Reactive Protein / Q000378:metabolism; D015331:Cohort Studies; D015179:Colorectal Neoplasms / Q000097:blood* / Q000175:diagnosis*; D055088:Early Detection of Cancer; D005260:Female; D006801:Humans; D008077:Lipoproteins, LDL / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009195:Peroxidase / Q000097:blood*
D008077:Lipoproteins, LDL; D002097:C-Reactive Protein; D009195:Peroxidase
LDL oxidized; antioxidants; cancer biomarkers; colorectal cancer; myeloperoxidase; oxidative stress