Inflammatory Biomarkers and Breast Cancer Risk: A Systematic Review of the Evidence and Future Potential for Intervention Research

White Blood Cell Count, Neutrophil-to-Lymphocyte Ratio, and Incident Cancer in the UK Biobank

BACKGROUND

The peripheral white blood cell (WBC) and neutrophil-to-lymphocyte ratio (NLR) reflect levels of inflammation and adaptive immunity. They are associated with cancer prognosis, but their associations with cancer incidence are not established.

METHODS

We evaluated 443,540 cancer-free adults in the UK Biobank with data on total WBC and its subsets, follow-up starting one year after baseline. Cox regression was used to estimate hazard ratios (HR) per quartile of WBC or NLR for incidence of 73 cancer types.

RESULTS

22,747 incident cancers were diagnosed during a median of 6.9 years of follow-up. WBC was associated with risk of cancer overall [HR, 1.05; 95% confidence interval (CI), 1.03-1.06], chronic lymphocytic leukemia/small lymphocytic leukemia (CLL/SLL, 2.79; 95% CI, 2.45-3.18), lung cancer (1.14, 95% CI, 1.08-1.20), and breast cancer (95% CI, 1.05-1.02-1.08). NLR was positively associated with cancer overall (HR, 1.03; 95% CI, 1.02-1.04, per quartile) and kidney cancer (1.16; 95% CI, 1.07-1.25), and inversely with CLL/SLL (0.38; 95% CI, 0.33-0.42).

CONCLUSIONS

High WBC or NLR may reflect excessive inflammatory status, promoting development of some cancers. Conversely, low NLR indicates a relative rise in lymphocytes, which could reflect an increase in circulating premalignant cells before CLL/SLL diagnosis. Peripheral WBC and NLR, in combination with other clinical information or biomarkers, may be useful tools for cancer risk stratification.

IMPACT

Elevated levels of WBCs or an increased NLR may indicate an overly active inflammatory response, potentially contributing to the eventual onset of certain types of cancer.

Hematological and biochemical markers influencing breast cancer risk and mortality: Prospective cohort study in the UK Biobank by multi-state models

BACKGROUND

Breast cancer is the most common cancer and the leading cause of cancer-related death among women. However, evidence concerning hematological and biochemical markers influencing the natural history of breast cancer from in situ breast cancer to mortality is limited.

METHODS

In the UK Biobank cohort, 260,079 women were enrolled during 2006-2010 and were followed up until 2019 to test the 59 hematological and biochemical markers associated with breast cancer risk and mortality. The strengths of these associations were evaluated using the multivariable Cox regression models. To understand the natural history of breast cancer, multi-state survival models were further applied to examine the effects of biomarkers on transitions between different states of breast cancer.

RESULTS

Eleven biomarkers were found to be significantly associated with the risk of invasive breast cancer, including mainly inflammatory-related biomarkers and endogenous hormones, while serum testosterone was also associated with the risk of in-situ breast cancer. Among them, C-reactive protein (CRP) was more likely to be associated with invasive breast cancer and its transition to death from breast cancer (HR for the highest quartile = 1.46, 95 % CI = 1.07-1.97), while testosterone and insulin-like growth factor-1 (IGF-1) were more likely to impact the early state of breast cancer development (Testosterone: HR for the highest quartile = 1.31, 95 % CI = 1.12-1.53; IGF-1: HR for the highest quartile = 1.17, 95 % CI = 1.00-1.38).

CONCLUSION

Serum CRP, testosterone, and IGF-1 have different impacts on the transitions of different breast cancer states, confirming the role of chronic inflammation and endogenous hormones in breast cancer progression. This study further highlights the need of closer surveillance for these biomarkers during the breast cancer development course.

The role of nutrition-based index in predicting survival of breast cancer patients: A systematic review and meta-analysis

Background

Prognostic nutritional index (PNI) and Controlling Nutritional Status (CONUT) are two model that incorporates the role of inflammation and nutrition factors to predict the progression of tumor. The primary objective of this investigation is to examine the ability of PNI and CONUT score for predicting the survival in breast cancer patients.

Methods

A comprehensive search was conducted on the Cochrane Library, Scopus, Europe PMC, and Medline databases up until August 14th, 2023, utilizing a combination of relevant keywords. This review incorporates literature that examines the relationship between PNI, CONUT, and survival in breast cancer. We employed random-effect models to analyze the hazard ratio (HR) and present the outcomes together with their corresponding 95 % confidence intervals (CI).

Results

A total of sixteen studies were incorporated. The results of our meta-analysis indicated that high PNI was associated with better overall survival (OS) (HR 0.38; 95%CI: 0.28-0.51, p < 0.00001, I2 = 32 %), but not disease-free survival (DFS) (HR 0.60; 95%CI: 0.33-1.10, p = 0.10, I2 = 78 %) than low PNI in breast cancer patients. Meta-analysis also indicated that high CONUT was associated with worse OS (HR 1.66; 95%CI: 1.21-2.28, p = 0.002, I2 = 78 %) and worse DFS (HR 2.09; 95%CI: 1.60-2.73, p < 0.00001, I2 = 41 %) in breast cancer patients.

Conclusions

This study suggests the prognostic role of both PNI and CONUT score for predicting survival in breast cancer patients.

Are dietary and serum advanced glycation end-products related to inflammation and oxidation biomarkers in breast cancer patients: a follow-up study

PURPOSE

This study is aimed at evaluating the relationship between dietary and serum advanced glycation end-products (AGEs) with serum inflammatory and oxidative stress biomarkers in breast cancer (BC).

METHODS

A sample of BC patients was followed for 12 months (March 2020-January 2022). Three-day food consumption record and serum samples were taken before surgery (T1), before chemotherapy (T2), at the 6^th month of chemotherapy (T3), and at the 12^th month of chemotherapy (T4). Dietary AGE intake was represented by carboxymethyl lysine (dCML). Serum levels of CML, inflammation, and oxidation biomarkers were determined with biochemical blood tests. The results were compared according to human epidermal growth factor receptor-2 (HER2) status.

RESULTS

Thirty-two women with BC and 32 age and body mass index-matched healthy women participated. No significant correlation was found between dCML and serum CML, inflammatory or oxidative stress biomarkers at T1, T2, and T4. A weak positive correlation was demonstrated between dCML and serum malondialdehyde levels (rho=0.355, p=0.046) at T3. The serum CML, inflammation, and oxidation biomarker levels of the HER2- group were significantly higher than those of the HER2+ group at T1.

CONCLUSION

This study suggests that there is limited correlation between dCML and serum inflammation and oxidative stress biomarkers in BC patients. Inflammation and oxidative biomarker levels appear to decline with treatment although dietary and serum AGE levels show not a corresponding significant decline. The HER2- subtype appears to be associated with higher dietary and serum AGEs and higher inflammatory and oxidative stress biomarkers.

Linking Physical Activity to Breast Cancer via Inflammation, Part 2: The Effect of Inflammation on Breast Cancer Risk

This review synthesized and appraised the evidence for an effect of inflammation on breast cancer risk. Systematic searches identified prospective cohort and Mendelian randomization studies relevant to this review. Meta-analysis of 13 biomarkers of inflammation were conducted to appraise the evidence for an effect breast cancer risk; we examined the dose-response of these associations. Risk of bias was evaluated using the ROBINS-E tool and the quality of evidence was appraised with Grading of Recommendations Assessment, Development, and Evaluation. Thirty-four observational studies and three Mendelian randomization studies were included. Meta-analysis suggested that women with the highest levels of C-reactive protein (CRP) had a higher risk of developing breast cancer [risk ratio (RR) = 1.13; 95% confidence interval (CI), 1.01-1.26] compared with women with the lowest levels. Women with highest levels of adipokines, particularly adiponectin (RR = 0.76; 95% CI, 0.61-0.91) had a reduced breast cancer risk, although this finding was not supported by Mendelian randomization analysis. There was little evidence of an effect of cytokines, including TNFα and IL6, on breast cancer risk. The quality of evidence for each biomarker ranged from very low to moderate. Beyond CRP, the published data do not clearly support the role of inflammation in the development of breast cancer.

High-intensity interval training improves metabolic syndrome in women with breast cancer receiving Anthracyclines

INTRODUCTION

Anthracycline chemotherapy is a frequent treatment for breast cancer, whereas it can increase risk of physiologic side-effects, such as metabolic syndrome (MetS). Exercise has been used as a non-pharmacological strategy to decrease MetS. Specifically, high-intensity interval training (HIIT) has been shown to improve MetS in patients with diabetes or cardiac rehabilitation patients; however, the effects of HIIT on MetS and associated biomarkers in patients with breast cancer receiving anthracycline chemotherapy have not been previously explored. Therefore, we purposed to determine the effects of HIIT on MetS in breast cancer patients undergoing anthracycline chemotherapy.

METHODS

In total, 30 patients with breast cancer were recruited prior to initiating treatment and randomized into HIIT (n = 15) or control (n = 15). The HIIT group attended supervised cycling sessions 3 days/week for 8 weeks. MetS was assessed by waist circumference, blood pressure, fasting levels of high-density lipoprotein cholesterol (HDL-C), triglycerides, and glucose. Circulating levels of MetS-related biomarkers were also measured (total cholesterol, insulin, HbA1c, leptin, adiponectin, and c-reactive protein).

RESULTS

After 8 weeks, MetS z-score was significantly improved in the HIIT group compared with controls (-7.60, 95% CI: -9.08 to -6.13, p < 0.001). MetS variables (HDL-C, glucose, and triglycerides) and circulating levels of MetS-related biomarkers were significantly improved in the HIIT group compared with controls (p < 0.001). Non-significant differences were found in body composition outcomes at the end of the study.

CONCLUSIONS

HIIT may be an effective strategy to improve MetS in breast cancer patients undergoing anthracycline chemotherapy. Furthermore, changes in MetS were independent of changes in body composition.

Prognostic Significance of Systemic Inflammation Markers in Testicular and Penile Cancer: A Narrative Review of Current Literature

In contemporary clinical practice, biomarkers are indispensable in the assessment and management of oncological patients. Although established serum tumor markers (beta human chorionic gonadotropin (bHCG), alpha fetoprotein (AFP), and lactate dehydrogenase (LDH)) have an indisputably important role in the management of patients with testicular cancer (TC), the application of these tumor markers may be accompanied with certain limitations, implying the need for additional biomarkers. Contrary to TC, there is a lack of established serological biomarkers for penile cancer (PC) and the management of this urological malignancy is based on multiple clinicopathological parameters. Therefore, the identification and rigorous analytical and clinical validation of reliable biomarkers are considered pivotal for improving PC management. Inflammation may be associated with all stages of oncogenesis, from initial neoplastic transformation to angiogenesis, tissue invasion, and metastasis. Accordingly, an array of inflammation-related indices have gained increasing attention as emerging predictors of oncological outcomes. The clinical usefulness of systemic inflammation markers was reported in many urological and non-urological malignancies. The aim of this narrative review is to summarize current scientific data regarding the prognostic and predictive significance of systemic inflammation markers in TC and PC patients.

Inflammatory biomarkers and risk of breast cancer among young women in Latin America: a case-control study

BACKGROUND

Breast cancer incidence is increasing rapidly in Latin America, with a higher proportion of cases among young women than in developed countries. Studies have linked inflammation to breast cancer development, but data is limited in premenopausal women, especially in Latin America.

METHODS

We investigated the associations between serum biomarkers of chronic inflammation (interleukin (IL)-6, IL-8, IL-10, tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), leptin, adiponectin) and risk of premenopausal breast cancer among 453 cases and 453 matched, population-based controls from Chile, Colombia, Costa Rica, and Mexico. Odds ratios (OR) were estimated using conditional logistic regression models. Analyses were stratified by size and hormonal receptor status of the tumors.

RESULTS

IL-6 (ORper standard deviation (SD) = 1.33 (1.11-1.60)) and TNF-α (ORper SD = 1.32 (1.11-1.58)) were positively associated with breast cancer risk in fully adjusted models. Evidence of heterogeneity by estrogen receptor (ER) status was observed for IL-8 (P-homogeneity = 0.05), with a positive association in ER-negative tumors only. IL-8 (P-homogeneity = 0.06) and TNF-α (P-homogeneity = 0.003) were positively associated with risk in the largest tumors, while for leptin (P-homogeneity = 0.003) a positive association was observed for the smallest tumors only.

CONCLUSIONS

The results of this study support the implication of chronic inflammation in breast cancer risk in young women in Latin America. Largest studies of prospective design are needed to confirm these findings in premenopausal women.

Protective effects of hesperidin through attenuation of Ki67 expression against DMBA-induced breast cancer in female rats

AIMS

Doxorubicin (Dox) is routinely used for breast cancer treatment but toxicity and drug resistance limit its use. The objective of the study was to investigate the protective effects of hesperidin alone and in combination with doxorubicin against experimentally induced breast cancer in female rats.

METHODS

Breast cancer (BC) was induced by administration of 7,12-dimethylbenz(a)anthracene (DMBA) through subcutaneous injection into the 3rd right mammary gland of female Wistar rats. Hesperidin (Hes) pretreated groups were started with Hes (200 mg/kg) two weeks prior to DMBA induction. Animals were randomly divided into nine groups namely vehicle control, DMBA-induced, Dox 4 mg/kg, Dox 2 mg/kg, Hes (200 mg/kg), Hes (200 mg/kg) plus Dox 4 mg/kg treated groups and Hes pretreated groups treated with DMBA, Dox 4 mg/kg and Dox 2 mg/kg.

KEY FINDINGS

Hes pretreated groups showed reduced tumor occurrence, tumor volume and increased survival rate as compared to DMBA-induced group of animals. Hes pretreated animals treated with Dox 4 mg/kg and 2 mg/kg exhibited significant reduction in malondialdehyde and improvement in levels of glutathione and inflammatory markers like IL-6, TNF-α, NF-κB, IFN-γ as compared to Dox 4 mg/kg and 2 mg/kg treated animals. Histopathology and Ki67 expression depicted better control of tumor with Hes pretreatment groups as compared to DMBA-induced. Histopathology of vital organs of Hes pretreated groups treated with Dox revealed lesser toxicity than Dox treated groups.

SIGNIFICANCE

Hesperidin possesses protective effect against experimentally induced breast cancer in female rats that appears to be related to attenuation of Ki67 expression.

Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols (FODMAPs) and cancer risk in the prospective NutriNet-Santé cohort

BACKGROUND

Fermentable Oligosaccharides, Disaccharides and Monosaccharides And Polyols (FODMAPs) have been shown to be involved in gastrointestinal disorders. In view of their pro-inflammatory potential and their interactions with the gut microbiota, their contribution to the etiology of other chronic diseases such as cancer has been postulated. However, no epidemiological study has investigated this hypothesis so far.

OBJECTIVE

Our objective was to investigate the associations between FODMAP intake (total and by type) and cancer risk (overall, breast, prostate and colorectal) in a large prospective cohort.

DESIGN

The study was based on the NutriNet-Santé cohort (2009-2020); 104,909 adult participants without cancer at baseline were included in our analyses (median follow-up time = 7.7y, 78.7% women, mean age at baseline 42.1y (SD = 14.5)). Baseline dietary intakes were obtained from repeated 24h-dietary records linked to a detailed food composition table. Associations between FODMAP intake (expressed in quintiles, Q) and cancer risks were assessed by Cox proportional hazard models adjusted for a large range of lifestyle, sociodemographic and anthropometric variables.

RESULTS

Total FODMAP intake was associated with increased overall cancer risk (n = 3374 incident cases, HR for sex-specific Quintile 5 versus Quintile 1: 1.21; 95%CI: 1.02, 1.44; P-trend = 0.04). In particular, oligosaccharides were associated with cancer risk: a trend was observed for overall cancer (HR Q5 vs. Q1: 1.10; 95%CI: 0.97, 1.25; P-trend = 0.04) and colorectal cancer (n = 272, HR Q5 vs. Q1: 1.78; 95%CI: 1.13-2.79; P-trend = 0.02).

CONCLUSION

Results from this large population-based study on French adults from the NutriNet-Santé cohort show a significant association between FODMAP intake and the risk of cancer development. Further epidemiological and experimental studies are needed to confirm these results and provide data on the potential underlying mechanisms.

Mediterranean Diet and Physical Activity: Two Imperative Components in Breast Cancer Prevention

Despite tremendous advances in medicine over the past few decades and significantly improved understanding of the symptomology and contributors to breast cancer (BC) incidence, BC rates continue to rise worldwide, with BC being a leading cause of cancer-related death among women. To reduce BC incidence, it is necessary to focus on promoting prevention strategies through a population-based approach of lowering exposure to modifiable risk factors in addition to the application of newer drug interventions (chemoprevention) for prevention in high-risk populations. Currently, available data suggest that lifestyle modifications through a healthy diet and increased physical activity (PA) play a crucial role in BC prevention; specifically, there is growing evidence to indicate that the Mediterranean diet (MeD) lowers cancer risk. This review summarizes the potential role of the MeD and PA in reducing BC risk, with an additional focus on microbial modulation in BC prevention, based on the current evidence obtained from PubMed. After reviewing the immunomodulatory and anticarcinogenic effects of both the MeD and PA, we conclude that further evaluation and proper implementation of both interventions can significantly reduce the risk of BC and associated mortality in the general population.

Human Saliva as a Diagnostic Specimen for Early Detection of Inflammatory Biomarkers by Real-Time RT-PCR

Nowadays human saliva is more frequently studied as a non-invasive, stress-free, and preferable diagnostic material than blood. Supporting evidences acknowledge saliva as a mirror that reflects the body’s physical state. Numerous studies have also demonstrated the presence and use of RNA derived from saliva in the early diagnosis of disease by real-time reverse transcriptase polymerase chain reaction (RT-PCR). Assessing the host inflammatory response in patients and its resolution at an early stage can serve as a prognostic and predictive method in determining therapeutic response or disease progression. In this context, the potential of saliva as a specimen to diagnose early inflammatory biomarkers using RT-PCR seems fascinating and useful. Here, we review inflammatory biomarkers within the saliva, focusing on early detection of these biomarkers using RT-PCR and the factors influencing the quality of saliva specimen.

Crown-Like Structures in Breast Adipose Tissue: Early Evidence and Current Issues in Breast Cancer

Simple Summary

Obesity increases the risk of postmenopausal, hormone receptor-positive breast cancer and has been linked to a higher risk of recurrence and mortality. During obesity, adipose tissue can become dysfunctional, resulting in chronic low-grade inflammation. Crown-like structures in breast adipose tissue (CLS-B), composed of macrophages surrounding dead or dying adipocytes in a crown-like pattern, are a new histologic marker of local inflammation. In this review, we aim to evaluate the early evidence of CLS-B in breast cancer. There is consistent evidence that CLS-B are more frequently detected among obese compared to non-obese breast cancer patients. Additionally, several studies have found that CLS-B presence is associated with metabolic and inflammatory factors that contribute to breast cancer development and progression. However, more studies are needed to understand the potential clinical utility of CLS-B as a marker of breast cancer risk or prognosis.

Abstract

Obesity is an established risk factor for postmenopausal breast cancer and has been linked to worse breast cancer prognosis, most clearly for hormone receptor-positive breast cancers. The underlying mechanisms of the obesity–breast cancer association are not fully understood, but growing evidence points to the breast adipose tissue microenvironment playing an important role. Obesity-induced adipose tissue dysfunction can result in a chronic state of low-grade inflammation. Crown-like structures of the breast (CLS-B) were recently identified as a histologic marker of local inflammation. In this review, we evaluate the early evidence of CLS-B in breast cancer. Data from preclinical and clinical studies show that these inflammatory lesions within the breast are associated with local NF-κB activation, increased aromatase activity, and elevation of pro-inflammatory mediators (TNFα, IL-1β, IL-6, and COX-2-derived PGE₂)—factors involved in multiple pathways of breast cancer development and progression. There is also substantial evidence from epidemiologic studies that CLS-B are associated with greater adiposity among breast cancer patients. However, there is insufficient evidence that CLS-B impact breast cancer risk or prognosis. Comparisons across studies of prognosis were complicated by differences in CLS-B evaluation and deficiencies in study design, which future studies should take into consideration. Breast adipose tissue inflammation provides a plausible explanation for the obesity–breast cancer association, but further study is needed to establish its role and whether markers such as CLS-B are clinically useful.

Weight Regain and Breast Cancer-Related Biomarkers Following an Exercise Intervention in Postmenopausal Women

BACKGROUND

Epidemiologic studies have reported associations between weight fluctuations and postmenopausal breast cancer risk; however, the biological markers involved in this association are unknown. This study aimed to explore the associations between breast cancer-related biomarkers and weight regain following exercise-induced weight loss.

METHODS

From the 400 participants included in the Breast Cancer and Exercise Trial in Alberta, a total of 214 lost weight during the intervention and had follow-up blood samples, body composition, and covariate measurements. Outcomes were measured at baseline, 12 months (end of the study), and 24 months (follow-up).

RESULTS

During follow-up, weight regain was 1.80 kg [95% confidence interval (CI): -0.40-3.90], and was significantly associated with increases in estradiol [treatment effect ratio (TER) = 1.03; 95% CI, 1.01-1.04], estrone (TER = 1.02; 95% CI, 1.01-1.03), free estradiol (TER = 1.04; 95% CI, 1.02-1.05), the homeostatic model assessment for insulin resistance (TER = 1.03; 95% CI, 1.02-1.05), and insulin (TER = 1.03; 95% CI, 1.01-1.04), and decreases in sex hormone-binding globulin (SHBG; TER = 0.98; 95% CI, 0.97-0.99) levels. Nonstatistically significant associations were found for glucose and C-reactive protein. Furthermore, a statistically significant linear trend of increasing levels for all biomarkers, and decreasing SHBG, across weight regain categories was found.

CONCLUSIONS

These results suggest that weight regain following exercise-induced weight loss is associated with breast cancer-related biomarker changes in postmenopausal women.

IMPACT

These findings provide evidence to support the importance of developing effective strategies to prevent weight regain and, consequently, decrease postmenopausal breast cancer risk via changes in adiposity-related biomarkers.

Current Resources for Evidence-Based Practice, March 2021

An extensive review of new resources to support the provision of evidence-based care for women and infants. The current column includes a discussion of men's experiences of pregnancy loss and commentaries on reviews focused on the effects of perineal massage on perineal trauma and air pollution and heat exposure on birth outcomes.

Recent Discoveries of Macromolecule- and Cell-Based Biomarkers and Therapeutic Implications in Breast Cancer

Breast cancer is the most commonly diagnosed cancer type and the leading cause of cancer-related mortality in women worldwide. Breast cancer is fairly heterogeneous and reveals six molecular subtypes: luminal A, luminal B, HER2+, basal-like subtype (ER−, PR−, and HER2−), normal breast-like, and claudin-low. Breast cancer screening and early diagnosis play critical roles in improving therapeutic outcomes and prognosis. Mammography is currently the main commercially available detection method for breast cancer; however, it has numerous limitations. Therefore, reliable noninvasive diagnostic and prognostic biomarkers are required. Biomarkers used in cancer range from macromolecules, such as DNA, RNA, and proteins, to whole cells. Biomarkers for cancer risk, diagnosis, proliferation, metastasis, drug resistance, and prognosis have been identified in breast cancer. In addition, there is currently a greater demand for personalized or precise treatments; moreover, the identification of novel biomarkers to further the development of new drugs is urgently needed. In this review, we summarize and focus on the recent discoveries of promising macromolecules and cell-based biomarkers for the diagnosis and prognosis of breast cancer and provide implications for therapeutic strategies.