Oxidized LDL, serum oxidizability and serum lipid levels in patients with breast or ovarian cancer

Objectives: The aim of this study was to evaluate the extent of oxidative stress in patients with breast or ovarian cancer by analyzing the magnitude of serum oxidizability and the involvement of oxidized low-density lipoproteins (oxLDL) in the disease. Design and methods: The study was conducted on 32 patients diagnosed with breast or ovarian cancer but who had not undergone any kind of treatment and 30 healthy individuals of similar age. The evaluation of oxidative stress was assessed by: (a) the ex-vivo susceptibility of serum lipids to oxidation and (b) the detection of oxLDL and anti-oxLDL autoantibodies. Total cholesterol, LDL-cholesterol and HDL-cholesterol were co-estimated. Results: The results indicated that the levels of oxLDL were increased among both breast and ovarian cancer patients as compared to the control subjects. Additionally in patients with breast cancer, serum total cholesterol, LDL-cholesterol, anti-oxLDL antibodies and the maximal rate of diene formation (RA), the index of oxidizable components load, were increased in comparison to controls. There is statistically significant evidence that serum oxLDL levels are associated with increased risk of breast and ovarian cancer. Conclusions: The findings exhibit a correlation between oxLDL and malignancy, supporting the contribution of oxidative stress to carcinogenesis and the possible involvement of oxLDL in the process of malignancy. The clinical evaluation of the oxLDL measurement is under investigation. © 2007 The Canadian Society of Clinical Chemists

Circulating oxidized low density lipoprotein, autoantibodies against them and homocysteine serum levels in diagnosis and estimation of severity of coronary artery disease

The oxidative hypothesis of atherosclerosis proposes that oxidative modification of low density lipoprotein (LDL) plays a critical role in atherogenesis. The evaluation of LDL oxidation in vivo is therefore very important. However, data concerning the evaluation of the above biochemical marker is very limited in clinical practice. Ibis study was conducted to test the hypothesis that plasma levels of ox-LDL reflect atherosclerosis and determine the clinical significance in the measurement of circulating ox-LDL and autoantibodies against them as well as their correlation with homocysteine and lipid parameters in the diagnosis and severity of coronary heart disease. A total of 273 in dividuals were examined: 41 suffering from unstable angina pectoris (UAP), 62 from stable angina pectoris (SAP) and 170 healthy control subjects. We used a sensitive method for detecting ox-LDL that is based on a direct sandwich technique (ELISA) in which two monoclonal antibodies are directed against separate antigenic determinants on the oxidized apolipoprotein-B molecule along with another enzyme immunoassay designed to determine human antibodies to oxidized LDL (anti-oxLDL) directly in serum. Total homocysteine (HCY) was evaluated by means of a fully automated fluorescence polarization immunoassay. Patients with UAP exhibited marked elevations in oxLDL levels as compared to patients with SAP (161.2 +/- 28.4 vs. 119.2 +/- 26.6, p < 0.001) and the control subjects (67 +/- 18.8, p < 0.001). The difference in oxLDL levels between patients with SAP and the control group was also statistically significant. Similarly, patients with UAP showed marked elevations in anti-oxLDL antibodies compared to both patients with SAP (602,2 +/- 62.2 vs. 510.8 +/- 50.3, p < 0.001) and control subjects (368 +/- 79.6, p < 0.001). The difference in anti-oxLDL levels between patients with SAP and the controls was also statistically significant. OxLDL levels were not correlated with age in any of the groups studied. Triglycerides, LDL-cholesterol and total cholesterol were elevated in patients with UAP as opposed to patients with SAP and the control subjects, while HDL levels were elevated in the control subjects when compared to patients with SAP and UAP. Homocysteine levels were elevated in patients suffering from UAP and SAP when compared to healthy subjects. Patients with UAP or SAP did not differ on homocysteine levels. Our findings demonstrate the presence of oxLDL in vivo, its strong association with coronary artery disease as well as with the severity of the clinical presentation

Oxidized LDL, serum oxidizability and serum lipid levels in patients with breast or ovarian cancer

Objectives: The aim of this study was to evaluate the extent of oxidative stress in patients with breast or ovarian cancer by analyzing the magnitude of serum oxidizability and the involvement of oxidized low-density lipoproteins (oxLDL) in the disease. Design and methods: The study was conducted on 32 patients diagnosed with breast or ovarian cancer but who had not undergone any kind of treatment and 30 healthy individuals of similar age. The evaluation of oxidative stress was assessed by: (a) the ex-vivo susceptibility of serum lipids to oxidation and (b) the detection of oxLDL and anti-oxLDL autoantibodies. Total cholesterol, LDL-cholesterol and HDL-cholesterol were co-estimated. Results: The results indicated that the levels of oxLDL were increased among both breast and ovarian cancer patients as compared to the control subjects. Additionally in patients with breast cancer, serum total cholesterol, LDL-cholesterol, anti-oxLDL antibodies and the maximal rate of diene formation (RA), the index of oxidizable components load, were increased in comparison to controls. There is statistically significant evidence that serum oxLDL levels are associated with increased risk of breast and ovarian cancer. Conclusions: The findings exhibit a correlation between oxLDL and malignancy, supporting the contribution of oxidative stress to carcinogenesis and the possible involvement of oxLDL in the process of malignancy. The clinical evaluation of the oxLDL measurement is under investigation. © 2007 The Canadian Society of Clinical Chemists

Circulating oxidized LDL levels, current smoking and obesity in postmenopausal women

Objective: The aim of the present study was to estimate circulating oxidized low-density lipoprotein (oxLDL) levels in postmenopausal women and evaluate their association with obesity and smoking status. Design and methods: The study included 135 postmenopausal women aged 52-75 years. Forty of them were overweight (BMI 32.4 +/- 6.4) and non-smokers (Group A), 40 non-overweight (BMI 22.6 +/- 1.8) and smokers (Group B) and 55 non-overweight (BMI 23.5 +/- 1.4) and non-smokers (Group Q. oxLDL and antibodies against them (anti-oxLDL) were measured using ELISA. Serum total cholesterol, LDL, HDL and triglycerides were measured in an automated analyzer. Results: Total cholesterol, LDL, HDL and oxLDL serum levels were significantly elevated in Group A as compared to Group B or C, as well as oxLDL in Group B in comparison to Group C (p < 0.001). Triglycerides and anti-oxLDL were increased in Group A in comparison to Group C (p = 0.043 and 0.023). Total cholesterol, LDL, triglycerides and anti-oxLDL did not differ between Groups B and C, while HDL was decreased in Group B as compared to Group C (p < 0.001). A significant positive correlation was found between oxLDL and LDL in Group A (r = 0.53, p < 0.001) as well as in Group C (r = 0.955, p < 0.001) and a negative one between oxLDL and HDL in Group C (r = -0.933, p < 0.001). Regression analysis revealed that obesity was a stronger predictor of LDL oxidation than smoking. Conclusions: Postmenopausal obesity is involved in the process of LDL oxidation and appears to be a stronger predictor of LDL oxidation than smoking. Future studies are needed to confirm these associations. (C) 2008 Elsevier Ireland Ltd. All rights reserved