Plasma variation and reproducibility of oxidized LDL-cholesterol and low-grade inflammation biomarkers among participants of the Malmö Diet and Cancer cohort

Associations of body mass index and weight change with circulating levels of high-sensitivity C-reactive protein, proinflammatory cytokines, and adiponectin among breast cancer survivors

AIM

This study examined the associations of body mass index (BMI) and weight change with inflammatory markers among breast cancer survivors in Korea.

METHODS

A total of 495 women were included who had been diagnosed with primary breast cancer and survived for at least 6 months since the surgery. Information on the body weight and height of the participants was collected both at the study enrollment and diagnosis. The plasma levels of inflammatory markers were measured, including high-sensitivity C-reactive protein, interleukin (IL)-6, IL-8, tumor necrosis factor-α, and adiponectin. A summary z-score was calculated by summing up the z-scores of each biomarker. The least-square means and 95% confidence intervals (CIs) were calculated using a generalized linear model and odds ratios (ORs) and 95% CIs for the elevated levels of inflammatory markers with a multivariate logistic regression model.

RESULTS

Participants with a BMI ≥27.5 kg/m² at the study enrollment and at diagnosis were significantly associated with elevated summary z-scores compared to those with a BMI < 23 kg/m² ; the ORs (95% CIs) were 5.42 (2.15-13.71) for current BMI and 3.66 (1.68-7.98) for BMI at diagnosis, respectively. Additionally, a weight loss > 5% since diagnosis was associated with a lower prevalence of high summary z-scores; the OR (95% CI) was .20 (.08-.52) compared to a stable weight.

CONCLUSIONS

A high BMI at diagnosis and current BMI with a greater degree were associated with unfavorable levels of inflammatory markers among breast cancer survivors. Additionally, weight loss since diagnosis was inversely associated with these markers.

Associations of Interleukin-5 With Plaque Development and Cardiovascular Events

Experimental studies have suggested an atheroprotective role of interleukin (IL)-5 through the stimulation of natural immunoglobulin M antibody expression. In the present study we show that there are no associations between baseline levels of IL-5 and risk for development of coronary events or stroke during a 15.7 ± 6.3 years follow-up of 696 subjects randomly sampled from the Malmö Diet and Cancer study. However, presence of a plaque at the carotid bifurcation was associated with lower IL-5 and IL-5 deficiency resulted in increased plaque development at sites of oscillatory blood flow in Apoe ^-/- mice suggesting a protective role for IL-5 in plaque development.

Low-Grade Inflammation, Oxidative Stress and Risk of Invasive Post-Menopausal Breast Cancer - A Nested Case-Control Study from the Malmö Diet and Cancer Cohort

OBJECTIVE

Although cancer promotes inflammation, the role of inflammation in tumor-genesis is less well established. The aim was to examine if low-grade inflammation is related to post-menopausal breast cancer risk, and if obesity modifies this association.

METHODS

In the Malmö Diet and Cancer cohort, a nested case-control study was defined among 8,513 women free of cancer and aged 55-73 years at baseline (1991-96); 459 were diagnosed with invasive breast cancer during follow-up (until December 31st, 2010). In laboratory analyses of blood from 446 cases, and 885 controls (matched on age and date of blood sampling) we examined systemic inflammation markers: oxidized (ox)-LDL, interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor (TNF)-α, white blood cells, lymphocytes and neutrophils. Odds ratios (OR) and 95% confidence intervals (CI) for breast cancer risk was calculated using multivariable conditional logistic regression.

RESULTS

Inverse associations with breast cancer were seen in fully-adjusted models, for 2nd and 3rd tertiles of ox-LDL, OR (95% CI): 0.65 (0.47-0.90), 0.63 (0.45-0.89) respectively, p-trend = 0.01; and for the 3rd tertile of TNF-α, 0.65 (0.43-0.99), p-trend = 0.04. In contrast, those in the highest IL-1β category had higher risk, 1.71 (1.05-2.79), p-trend = 0.01. Obesity did not modify associations between inflammation biomarkers and breast cancer.

CONCLUSION

Our study does not suggest that low-grade inflammation increase the risk of post-menopausal breast cancer.