title: Measurement of serum paraoxonase activity and MDA concentrations in patients suffering with oral squamous cell carcinoma.
abstract: BACKGROUND
  Oxidative stress is associated with many diseases including cancer. Oral squamous cell carcinoma (OSCC) is a prevalent cancer involving oral cavity. We evaluate the activity of paraoxonase 1 (PON1) in serum samples of subjects suffering from OSCC along with malondialdehyde (MDA) levels, a marker for oxidative stress. Antioxidant status in OSCC may reflect the role of oxidative imbalance in the disease.
  
  
  METHODS
  Forty-five patients suffering with OSCC and 30 healthy controls were selected for the study. Serum paraoxonase (PON) and arylesterase (ARE) activities were measured in subjects suffering from OSCC and their healthy counterparts. To examine the status of lipid peroxidation, MDA concentrations were estimated and a correlation was determined between PON activities and MDA concentrations. MDA expression in cancer and normal adjacent tissue was studied through immunohistochemical (IHC) analysis. Total reactive oxygen species (ROS) level was determined in serum from normal and diseased subjects. Our results revealed that both PON and ARE activities of PON1 were significantly decreased in OSCC patients. Serum MDA concentrations were inversely correlated to PON activity. Immunohistochemical analysis showed a higher expression of MDA in cancerous tissue. Total ROS levels were found to be significantly elevated in cancer subjects.
  
  
  CONCLUSIONS
  Along with other antioxidants, PON levels may act as an indicator of oxidative stress in cancer.
authors.affiliation: National Center for Proteomics, University of Karachi, Karachi, Pakistan.
authors.forename: Uzma Urooj
authors.initials: UU
authors.lastname: Malik
authors.affiliation: Department of ENT, Jinnah Postgraduate Medical Center, Karachi, Pakistan.
authors.forename: Imtiaz Ather
authors.initials: IA
authors.lastname: Siddiqui
authors.affiliation: National Center for Proteomics, University of Karachi, Karachi, Pakistan.
authors.forename: Zehra
authors.initials: Z
authors.lastname: Hashim
authors.affiliation: National Center for Proteomics, University of Karachi, Karachi, Pakistan. Electronic address: szarina@uok.edu.pk.
authors.forename: Shamshad
authors.initials: S
authors.lastname: Zarina
mesh_terms: D000328:Adult; D043303:Aryldialkylphosphatase / Q000097:blood* / Q000378:metabolism; D002265:Carboxylic Ester Hydrolases / Q000097:blood / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000097:blood* / Q000201:enzymology / Q000378:metabolism*; D004789:Enzyme Activation; D005260:Female; D006801:Humans; D015227:Lipid Peroxidation; D008297:Male; D008315:Malondialdehyde / Q000097:blood*; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000097:blood* / Q000201:enzymology / Q000378:metabolism*; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D017382:Reactive Oxygen Species; D008315:Malondialdehyde; D002265:Carboxylic Ester Hydrolases; C019734:arylesterase; D043303:Aryldialkylphosphatase; C468406:PON1 protein, human
keywords: Arylesterase activity; Lipid peroxidation; Malondialdehyde; Oral squamous cell carcinoma; Oxidative stress; Paraoxonase activity