Exploring the effects of lifestyle on breast cancer risk, age at diagnosis, and survival: the EBBA-Life study

Purpose

Whether an unfavorable lifestyle not only affects breast cancer risk, but also influences age at onset of breast cancer and survival, is under debate.

Methods

In a population-based cohort, the Energy Balance and Breast Cancer Aspects throughout life (EBBA-Life) study, a total of 17,145 women were included. During follow-up, 574 women developed invasive breast cancer. Breast cancer cases were followed for an additional 9.1 years. Detailed medical records were obtained. Cox’s proportional hazard regression models were used to study the association between pre-diagnostic lifestyle factors (weight, physical activity, alcohol use, smoking, and hypertension), breast cancer risk, age at diagnosis, and survival.

Results

At study entry, 34.3% of the participating women were overweight and 30.7% were physically inactive. Mean age at breast cancer diagnosis was 58.0 years, and 78.9% of the tumors were estrogen receptor positive. Among menopausal women who did not use hormone therapy and had an unfavorable lifestyle (3–5 unfavorable factors), compared with women who had a favorable lifestyle, we observed a twofold higher risk for postmenopausal breast cancer (hazard ratio [HR] 2.13, 95% confidence interval [CI] 1.23–3.69), and they were 3.4 years younger at diagnosis (64.8 versus 68.2 years, P = 0.032). Breast cancer patients with an unfavorable lifestyle, compared with patients with a favorable lifestyle, had almost a two times higher overall mortality risk (HR 1.96, 95% CI 1.01–3.80).

Conclusions

Our study supports a healthy lifestyle improving breast cancer prevention, postponing onset of disease, and extending life expectancy among breast cancer patients.

Electronic supplementary material

The online version of this article (10.1007/s10549-020-05679-2) contains supplementary material, which is available to authorized users.

Impact of pre-diagnostic triglycerides and HDL-cholesterol on breast cancer recurrence and survival by breast cancer subtypes

BACKGROUND

High triglycerides and low levels of high density lipoprotein (HDL)-cholesterol are observed to promote tumor growth. However, whether breast cancer heterogeneity may explain the contradictory influence of triglycerides and cholesterol observed on breast cancer prognosis remains unclear.

METHODS

A population-based survival study among 464 breast cancer cases identified within the Tromsø study was conducted. Pre-diagnostic triglycerides, total-cholesterol and HDL-cholesterol were measured, and detailed clinical and histopathological data were obtained. Using tissue microarray, all breast cancer cases were reclassified into the following subtypes: Luminal A, Luminal B, HER2-enriched, and triple negative breast cancer (TNBC). Multivariable Cox proportional hazards regression models were used to study the associations between pre-diagnostic lipids and breast cancer recurrence, mortality, and survival.

RESULTS

A total of 464 breast cancer patients, with mean age at diagnosis of 57.9 years, were followed for a mean 8.4 years. TNBC patients in the highest tertile of triglycerides (≥ 1.23 mmol/l) had 3 times higher overall mortality compared to TNBC patients in the lowest tertile (≤ 0.82 mmol/l) (HR 2.99, 95% CI 1.17-7.63), and the 5-year overall survival was 19% lower for TNBC patients in the highest vs. lowest tertile of triglycerides (65% vs. 84%). TNBC patients in the highest tertile of the HDL-cholesterol/total-cholesterol ratio (≥0.35), compared to those in the lowest tertile (≤0.27), had a 67% reduced overall mortality risk (HR 0.33, 95% CI 0.12-0.89). No associations were observed between lipids and prognostic outcome among breast cancer patients overall, or among patients with luminal A and luminal B subtypes. Among HER2-enriched patients, pre-diagnostic triglyceride level was inversely associated with overall mortality.

CONCLUSION

Our study suggests that pre-diagnostic triglycerides and the HDL-cholesterol/total-cholesterol ratio may independently provide unique information regarding prognostic outcome among triple negative breast cancer patients. However, a small sample size underlines the need for additional studies.

Abstract P4-12-02: Serum-triglycerides among triple negative breast cancer patients as a biomarker of poor outcome

Backgound: Obesity and related metabolic imbalances, including increased activity of free fatty acids, may promote tumor growth and metastasis. Fatty acids are mainly stored as triacylglycerols. Yet, the role of serum-triglycerides on breast cancer prognosis is still undefined.

Methods: A population based survival study among 575 breast cancer patients identified within the Tromsø study during 1979-2008, was conducted. Pre-diagnostic serum triglycerides, high density lipoprotein-cholesterol, total cholesterol, height and weight were measured. Histopathological and clinical data were obtained from medical records, and hormone receptor, HER2 status, and Ki-67 were re-analyzed on tissue microarray blocks. Multivariate Cox proportional Hazard regression models were used to study the associations between patient characteristics including s-triglycerides, and breast cancer survival.

Results: Among 575 women with invasive breast cancer (stage 1-3), a total of 87 women were diagnosed with triple negative breast cancer (TNBC). Patients diagnosed with TNBC, compared to non-TNBC, were likely to be younger at diagnosis (55.3 vs 57.9 years, p=0.061), they had larger tumors (29.7 mm vs 22.5 mm, p=0.001), and higher Ki-67 (31.1% vs 15.9%, p<0.001). After a mean follow-up of 8.4 years, TNBC patients with above median levels of s-triglycerides (> 0.98mmol/L) compared to TNBC patients with below median levels of s-triglycerides (≤ 0.98mmol/L) had 3.0 times higher risk for breast cancer recurrence or breast cancer specific death (HR 3.02, 95% CI 1.21-7.55), and 3.4 times higher overall mortality risk (HR 3.41, 95% CI 1.38-8.45). Among the TNBC patients, women with above median s-triglycerides had 15% lower 5-year disease-free survival (76% vs 91%) and 18% lower 5-year overall survival (74% vs 92%) compared to women with below median s-triglycerides.

Conclusions: Our results strongly support s-triglycerides as an important biomarker for breast cancer outcomes among triple negative breast cancer patients.

Table 1: Multivariable adjusted Hazard Ratios (HRs) for incidence breast cancer recurrence or breast cancer specific death, and incidence overall mortality by pre-diagnostic serum-triglycerides among non-triple negative breast cancer (TNBC) and TNBC patients  Non-TNBC, n=488 TNBC, n=87  Recurrence or breast cancer specific death (n=90)Overall mortality (n=104) Recurrence or breast cancer specific death (n=24)Overall mortality (n=33) nHR (95% CI)HR (95% CI)nHR (95% CI)HR (95% CI)s-Triglycerides      Median      ≤ 0.98 mmol/l2571.001.00431.001.00> 0.98 mmol/l2310.87 (0.56-1.35)1.06 (0.70-1.62)443.02 (1.21-7.55)3.41 (1.38-8.45)       Tertiles      ≤ 0.82 mmol/l1731.001.00261.001.000.83 – 1.22 mmol/l1660.74 (0.44-1.23)0.81 (0.49-1.36)311.37 (0.38-4.98)0.98 (0.31-3.08)≥ 1.23 mmol/l1490.88 (0.50-1.54)1.17 (0.66-1.96)306.63 (1.64-19.3)3.87 (1.52-12.0)p-trend 0.4950.357 0.0050.007       Multivariate Cox proportional Hazard regression model. Adjusted for BMI and age at attendance (continuous), age at diagnosis (continuous), breast cancer stage at diagnosis (categorical), and current smoking (categorical). Abbreviation: CI, confidence interval; n, number of cases; TNBC, triple negative breast cancer

Citation Format: Lofterød T, Mortensen ES, Nalwoga H, Wilsgaard T, Frydenberg H, Risberg T, Eggen AE, McTiernan A, Aziz S, Wist EA, Reitan JB, Akslen LA, Thune I. Serum-triglycerides among triple negative breast cancer patients as a biomarker of poor outcome [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-12-02.

Pre-diagnostic high-sensitive C-reactive protein and breast cancer risk, recurrence, and survival

Inflammation may initiate and promote breast cancer development, and be associated with elevated circulating levels of inflammation markers. A total of eight 130 initially healthy women, participated in the population-based Tromsø study (1994-2008). Pre-diagnostic high-sensitivity C-reactive protein (hs-CRP) was assessed. During 14.6 years of follow-up, a total of 192 women developed invasive breast cancer. These cases were followed for additional 7.2 years. Detailed medical records were obtained. We observed an overall positive dose-response relationship between pre-diagnostic hs-CRP and breast cancer risk (hazard ratio (HR) = 1.06, 95 % CI 1.01-1.11). Postmenopausal women with above median levels of hs-CRP (>1.2 mg/l) had a 1.42 (95 % CI 1.01-2.00) higher breast cancer risk compared to postmenopausal women with hs-CRP below median. Postmenopausal women, who were hormone replacement therapy non-users, and were in the middle tertile (0.8-1.9 mg/l), or highest tertile of hs-CRP (>1.9 mg/l), had a 2.31 (95 % CI 1.31-4.03) and 2.08 (95 % CI 1.16-3.76) higher breast cancer risk, respectively, compared with women in the lowest tertile. For each unit increase in pre-diagnostic hs-CRP levels (mg/l), we observed an 18 % increase in disease-free interval (95 % CI 0.70-0.97), and a 22 % reduction in overall mortality (95 % CI 0.62-0.98). Our study supports a positive association between pre-diagnostic hs-CRP and breast cancer risk. In contrast, increased pre-diagnostic hs-CRP was associated with improved overall mortality, but our findings are based on a small sample size, and should be interpreted with caution.

Tertiary lymphoid structures are associated with higher tumor grade in primary operable breast cancer patients

Background

Tertiary lymphoid structures (TLS) are highly organized immune cell aggregates that develop at sites of inflammation or infection in non-lymphoid organs. Despite the described role of inflammation in tumor progression, it is still unclear whether the process of lymphoid neogenesis and biological function of ectopic lymphoid tissue in tumors are beneficial or detrimental to tumor growth. In this study we analysed if TLS are found in human breast carcinomas and its association with clinicopathological parameters.

Methods

In a patient group (n = 290) who underwent primary surgery between 2011 and 2012 we assessed the interrelationship between the presence of TLS in breast tumors and clinicopathological factors. Prognostic factors were entered into a binary logistic regression model for identifying independent predictors for intratumoral TLS formation.

Results

There was a positive association between the grade of immune cell infiltration within the tumor and important prognostic parameters such as hormone receptor status, tumor grade and lymph node involvement. The majority of patients with high grade infiltration of immune cells had TLS positive tumors. In addition to the degree of immune cell infiltration, the presence of TLS was associated with organized immune cell aggregates, hormone receptor status and tumor grade. Tumors with histological grade 3 were the strongest predictor for the presence of TLS in a multivariate regression model. The model also predicted that the odds for having intratumoral TLS formation were ten times higher for patients with high grade of inflammation than low grade.

Conclusions

Human breast carcinomas frequently contain TLS and the presence of these structures is associated with aggressive forms of tumors. Locally generated immune response with potentially antitumor immunity may control tumorigenesis and metastasis. Thus, defining the role of TLS formation in breast carcinomas may lead to alternative therapeutic approaches targeting the immune system.

Impact of the tumor necrosis factor receptor-associated protein 1 (Trap1) on renal DNaseI shutdown and on progression of murine and human lupus nephritis

Recent findings show that transformation of mild glomerulonephritis into end-stage disease coincides with shutdown of renal DNaseI expression in (NZBxNZW)F1 mice. Down-regulation of DNaseI results in reduced chromatin fragmentation and deposition of extracellular chromatin fragments in glomerular basement membranes where they appear in complex with IgG antibodies. Here, we implicate the anti-apoptotic and survival protein, tumor necrosis factor receptor-associated protein 1 (Trap1) in the disease process, based on the observation that annotated transcripts from this gene overlap with transcripts from the DNaseI gene. Furthermore, we translate these observations to human lupus nephritis. In this study, mouse and human DNaseI and Trap1 mRNA levels were determined by real-time quantitative PCR and compared with protein expression levels and clinical data. Cellular localization was analyzed by immune electron microscopy, IHC, and in situ hybridization. Data indicate that silencing of DNaseI gene expression correlates inversely with expression of the Trap1 gene. Our observations suggest that the mouse model is relevant for the aspects of disease progression in human lupus nephritis. Acquired silencing of the renal DNaseI gene has been shown to be important for progression of disease in both the murine and human forms of lupus nephritis. Early mesangial nephritis initiates a cascade of inflammatory signals that lead to up-regulation of Trap1 and a consequent down-regulation of renal DNaseI by transcriptional interference.

Heparin exerts a dual effect on murine lupus nephritis by enhancing enzymatic chromatin degradation and preventing chromatin binding in glomerular membranes

OBJECTIVE

Association of nucleosome-IgG immune complexes with glomerular basement membranes (GBMs) is an important event in the development of lupus nephritis. Preventing this binding and/or increasing nuclease sensitivity of nucleosomes may be viable strategies for the prevention of the disease. Theoretically, heparin may alter nucleosomal structure and increase sensitivity to proteinases and nucleases, and may also inhibit binding of nucleosomes and nucleosome-IgG complexes to basement membrane structures. The aim of this study was to investigate whether and eventually how heparin prevents murine lupus nephritis.

METHODS

Surface plasmon resonance was used to analyze if heparin inhibits binding of nucleosomes to laminin and collagen. The effect of heparin on nuclease- and proteinase-mediated degradation of nucleosomes was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and agarose gel electrophoresis. In vitro results were compared with analyses in vivo in heparin-treated (NZB × NZW)F(1) mice. Anti-double-stranded DNA antibody production, deposition of nucleosome-IgG complexes in GBMs, and development of proteinuria were monitored, and circulating chromatin fragments were quantified using quantitative polymerase chain reaction.

RESULTS

In vitro studies demonstrated that heparin increased enzymatic degradation of nucleosomes and almost completely inhibited binding of nucleosomes to laminin and collagen. (NZB × NZW)F(1) mice treated with heparin demonstrated delayed or no antibody production and higher variation of circulating chromatin levels compared with untreated control mice. This effect was accompanied by highly reduced nucleosome-IgG complexes in GBMs and delayed development of nephritis.

CONCLUSION

Increasing the degradation of nucleosomes, reducing their immunogenicity, and preventing binding of nucleosome-IgG complexes in glomeruli together provide an alternative basis for the treatment of lupus nephritis.

Circulating chromatin-anti-chromatin antibody complexes bind with high affinity to dermo-epidermal structures in murine and human lupus nephritis

Murine and human lupus nephritis are characterized by glomerular deposits of electron-dense structures (EDS). Dominant components of EDS are chromatin fragments and IgG antibodies. Whether glomerular EDS predispose for similar deposits in skin is unknown. We analysed (i) whether dermo-epidermal immune complex deposits have similar molecular composition as glomerular deposits, (ii) whether chromatin fragments bind dermo-epidermal structures, and (iii) whether deposits in nephritic glomeruli predispose for accumulation of similar deposits in skin. Paired skin and kidney biopsies from nephritic (NZBxNZW)F1 and MRL-lpr/lpr mice and from five patients with lupus nephritis were analysed by immunofluorescence, immune electron microscopy (IEM) and co-localization TUNEL IEM. Affinity of chromatin fragments for membrane structures was determined by surface plasmon resonance. Results demonstrated (i) presence of EDS containing chromatin fragments and IgG in both organs in nephritic patients, (ii) chromatin fragments possessed high affinity for dermo-epidermal laminins and collagens, (iii) glomerular immune complex deposits did not predict similar interstitial deposits in skin, although such complexes were present in capillary lumina in glomeruli and skin of all nephritic individuals. Thus, chromatin-IgG complexes accounting for lupus nephritis seem to reach skin through circulation, but other undetermined factors are required for these complexes to deposit within skin membranes.

Frequency of acute asymptomatic myocardial infarction and an estimate of infarct age in cases of abrupt sudden death observed in a forensic autopsy material

The aim of this study is to determine the frequency of acute infarcts at autopsy in cases of unexpected abrupt deaths in persons with coronary heart disease. In addition, we want to estimate the time between onset of infarct and death based on evolving tissue changes in the infarct known to occur during the first hours. Thirty cases of unexpected, abrupt deaths were selected from a forensic autopsy material. Half of them had a preliminary diagnosis of coronary heart disease, the other half a preliminary diagnosis not involving the heart or chest area. Complete autopsies were performed. The myocardium and the coronary arteries were sampled and examined without knowledge of the gross findings or to which group the case belonged. Myocardial infarcts and acute coronary changes were found in both groups, less frequently in the non-coronary group. The age of the myocardial and coronary lesions was estimated by observing morphological characteristics changing with time, e.g. increasing polymorphonuclear leucocytes in the infarcted myocardium, and increasing amount of fibrin in thrombi. The majority of cases in the coronary group died with an extensive asymptomatic myocardial infarction, which probably had lasted 5-6 hrs or less. Acute changes in the right coronary artery and its area of supply prevailed. Acute myocardial infarcts were observed also in a minority of the non-coronary group, but myocardial infarction was not the cause of death in any of them. Abrupt coronary death is most often preceded by an extensive asymptomatic myocardial infarction within the last 5-6 hrs.

Lupus nephritis: the central role of nucleosomes revealed

Systemic lupus erythematosus (SLE) is an autoimmune syndrome characterized by autoantibodies to nuclear constituents. Some of these antibodies are diagnostically important, whereas others act as disease-modifying factors. One clinically important factor is autoantibodies against dsDNA and nucleosomes, which have overlapping diagnostic and nephritogenic impact in SLE. Although a scientific focus for 5 decades, the molecular and cellular origin of these antibodies, and why they are associated with lupus nephritis, is still not fully understood. A consensus has, however, evolved that antibodies to dsDNA and nucleosomes are central pathogenic factors in the development of lupus nephritis. In contrast, no agreement has been reached as to which glomerular structures are bound by nephritogenic anti-nucleosome antibodies in vivo. Mutually contradictory paradigms and models have evolved simply because we still lack precise and conclusive data to provide definitive insight into how autoantibodies induce lupus nephritis and which specificity is critical in the nephritic process(es). In this review, data demonstrating the central role of nucleosomes in inducing and binding potentially nephritogenic antibodies to DNA and nucleosomes are presented and discussed. These autoimmune-inducing processes are discussed in the context of Matzinger's danger model (Matzinger P: Friendly and dangerous signals: is the tissue in control? Nat Immunol 2007, 8:11-13; Matzinger P: The danger model: a renewed sense of self. Science 2002, 296:301-305; Matzinger P: Tolerance, danger, and the extended family. Annu Rev Immunol 1994, 12:991-1045) and Medzhitov's and Janeway's (Medzhitov R, Janeway CA Jr: Decoding the patterns of self and nonself by the innate immune system. Science 2002, 296:298-300; Medzhitov R, Janeway CA Jr: How does the immune system distinguish self from nonself? Semin Immunol 2000, 12:185-188; Janeway CA Jr, Medzhitov R: Innate immune recognition. Annu Rev Immunol 2002, 20:197-216) distinction of noninfectious self (NIS) and infectious nonself (INS). The mechanisms leading to production of potentially nephritogenic anti-nucleosome antibodies and to overt lupus nephritis are interpreted in the context of these paradigms.

Glomerular expression of large polyomavirus T antigen in binary tet-off regulated transgenic mice induces apoptosis, release of chromatin and initiates a lupus-like nephritis

Binary tetracycline-regulated polyomavirus large T antigen transgenic mice were generated to study immunological tolerance for nucleosomes. Expression of T antigen resulted in binding of the protein to chromatin, and released T antigen-nucleosome complexes from dying cells maintained anti-dsDNA and anti-nucleosome antibody-production by activating autoimmune nucleosome-specific B cells and CD4+ and CD8+ T antigen specific T cells. Glomerular T antigen expression was observed in these mice. Here, we demonstrate that this expression was linked to glomerular cell apoptosis, release of nucleosomes and association of nucleosomes with glomerulus basement membranes, detected as electron dense structures. Immune electron microscopy (IEM) revealed that these structures were glomerular targets for induced anti-dsDNA and anti-T antigen antibodies. Co-localization IEM demonstrated that in vivo-bound auto-antibodies co-localized with experimental monoclonal antibodies to dsDNA and to T antigen. A comparative analysis of glomeruli from nephritic (NZWxNZB)F1 and T antigen expressing transgenic mice revealed deposition of nucleosomes in glomerular capillary and mesangial matrix membranes and binding of anti-nucleosome antibodies in both mice strains. A controlled experimental model that may elucidate the initial events accounting for nucleosome-mediated nephritis has not been available. The transgenic mouse may be important to describe early immunological and cellular events accounting for the enigmatic lupus nephritis.

Glomerular apoptotic nucleosomes are central target structures for nephritogenic antibodies in human SLE nephritis

Antibodies to double-stranded (dsDNA) are associated with systemic lupus erythematosus (SLE) and directly involved in human lupus nephritis. Information about their glomerular target antigens is inconsistent, and whether availability of target antigens, antibody specificity or avidity are nephritogenic parameters, is not determined. In this study, we analyzed renal tissue from anti-dsDNA antibody-positive lupus patients with nephritis by morphological and immunological assays, including immune electron microscopy (IEM) and colocalization IEM, an EM-based confocal microscopy assay. IEM demonstrated that antibody deposits were confined to electron dense structures (EDS) in glomerular membranes. These autoantibodies colocalized with nucleosome-binding anti-dsDNA/-histone/-transcription factor antibodies. To confirm the colocalization IEM-data, we developed a colocalization terminal deoxynucleotidyl-transferase (TdT) biotin-dUTP nicked end-labeled (TUNEL) IEM assay where extracellular DNA was traced by TdT-mediated introduction of biotinylated nucleotides and autoantibodies by IEM. Results consistently demonstrated that DNA colocalized with autoantibodies in glomerular membrane-associated EDS. The colocalization IEM and colocalization TUNEL IEM assays thus demonstrate that intra-glomerular membrane-associated nucleosomes are targeted by anti-dsDNA autoantibodies in human lupus nephritis. The data provide a new approach to understand basic molecular and immunological processes accounting for antibody-mediated nephritis in human SLE.

[Laboratory diagnosis of cobalamin deficiency. A comparative study of 2 serum cobalamin methods and serum methylmalonic acid]

The diagnosis of cobalamin deficiency is established traditionally by demonstration of lowered serum cobalamin, but, for many reasons it cannot be anticipated that the concentrations of cobalamins in the serum reflect the relationship between blood cobalamin and tissue cobalamin accurately. The blood methylmalonic acid which cannot be metabolized in cases of cellular cobalamin deficiency should, on the other hand, indicate the cobalamin available for the tissues. A blind, prospective, controlled investigation was undertaken to compare the clinical employability of a recently developed method for measurement of the concentration of methylmalonic acid in the serum with older and more recent methods of measuring serum cobalamins. The three methods classified 94, 72 and 74% of the patients correctly, respectively (n = 50). The results reveal that serum methylmalonic acid is a more sensitive and specific analysis for demonstrating whether cobalamin deficiency was present or not. Serum cobalamins measured by both methods are relatively insensitive and unspecific markers for cobalamin deficiency in the tissue. Low cobalamin concentrations do not indicate that the patient in question has cobalamin deficiency, and values in the lower half of the reference interval do not exclude cobalamin deficiency. Measurement of methylmalonic acid in the serum is recommended in patients with low-normal or low serum cobalamin.