C/EBPB-dependent adaptation to palmitic acid promotes tumor formation in hormone receptor negative breast cancer

Epidemiological studies have established a positive association between obesity and the incidence of postmenopausal breast cancer. Moreover, it is known that obesity promotes stem cell-like properties of breast cancer cells. However, the cancer cell-autonomous mechanisms underlying this correlation are not well defined. Here we demonstrate that obesity-associated tumor formation is driven by cellular adaptation rather than expansion of pre-existing clones within the cancer cell population. While there is no correlation with specific mutations, cellular adaptation to obesity is governed by palmitic acid (PA) and leads to enhanced tumor formation capacity of breast cancer cells. This process is governed epigenetically through increased chromatin occupancy of the transcription factor CCAAT/enhancer-binding protein beta (C/EBPB). Obesity-induced epigenetic activation of C/EBPB regulates cancer stem-like properties by modulating the expression of key downstream regulators including CLDN1 and LCN2. Collectively, our findings demonstrate that obesity drives cellular adaptation to PA drives tumor initiation in the obese setting through activation of a C/EBPB dependent transcriptional network.

Simultaneous Quantification of Aromatase Inhibitors and Estrogens in Postmenopausal Breast Cancer Patients

Context Currently there are no assays that can simultaneously quantify serum levels of the third generation aromatase inhibitors (AI); letrozole, anastrozole, and exemestane, and the ultralow levels of estrogens in postmenopausal breast cancer patients on AI treatment. Such measurements may be pivotal for the determination of optimal and individualized treatment regimens. We aimed at developing an LC-MS/MS method for simultaneous assessment of letrozole, anastrozole, exemestane and 17-hydroxy-exemestane as well as subpicomolar levels of estradiol and estrone. Methods Internal standards, calibrators, serum samples and quality controls were in fully automated steps transferred to a deepwell plate for a two-step liquid-liquid-extraction. The extracts were reconstituted and analytes were separated chromatographically using two serially coupled columns, then subject to MS/MS in ESI mode. The method was thoroughly validated and is traceable to two accredited estrogen-methods. Results Measurement range for estrone and estradiol was 0.2 – 12 000 pmol/L and 0.8 – 13 000 pmol/L, and covered the expected therapeutic range for the AIs. All analytes had precision ≤ 13 %, and accuracies within 100 ± 8 %. As proof-of-concept, AI and estrogen levels were determined in sera from postmenopausal breast cancer patients under treatment. Conclusions We present here an assay suitable for the simultaneous measurement of serum levels of all third generation AIs and ultralow levels of estrogens, providing a powerful new tool to study drug efficacy and compliance. The method is highly valuable for postmenopausal patients whose pretreatment estradiol levels are below threshold of detection for most routine assays, but still require suppression.

A Low-Glucose Eating Pattern Improves Biomarkers of Postmenopausal Breast Cancer Risk: An Exploratory Secondary Analysis of a Randomized Feasibility Trial

Postmenopausal breast cancer is the most common obesity-related cancer death among women in the U.S. Insulin resistance, which worsens in the setting of obesity, is associated with higher breast cancer incidence and mortality. Maladaptive eating patterns driving insulin resistance represent a key modifiable risk factor for breast cancer. Emerging evidence suggests that time-restricted feeding paradigms (TRF) improve cancer-related metabolic risk factors; however, more flexible approaches could be more feasible and effective. In this exploratory, secondary analysis, we identified participants following a low-glucose eating pattern (LGEP), defined as consuming energy when glucose levels are at or below average fasting levels, as an alternative to TRF. Results show that following an LGEP regimen for at least 40% of reported eating events improves insulin resistance (HOMA-IR) and other cancer-related serum biomarkers. The magnitude of serum biomarkers changes observed here has previously been shown to favorably modulate benign breast tissue in women with overweight and obesity who are at risk for postmenopausal breast cancer. By comparison, the observed effects of LGEP were similar to results from previously published TRF studies in similar populations. These preliminary findings support further testing of LGEP as an alternative to TRF and a postmenopausal breast cancer prevention strategy. However, results should be interpreted with caution, given the exploratory nature of analyses.

Combination of Endogenous Estradiol and Adipokine Leptin in Breast Cancer Risk and Prognosis Assessment in Postmenopausal Chinese Women

ObjectiveOur study aims to clarify the role of estradiol and leptin in breast cancer risk and prognostic assessment in postmenopausal Chinese women.DesignThe serum circulating estradiol and leptin level was detected by ELISA. Then the correlation between estradiol, leptin level, and clinical characteristics was analyzed using Fisher’s exact test. Next, the Kaplan-Meier model was used to analyze the association between estradiol, leptin, and prognosis of postmenopausal breast cancer patients in our cohort and the TCGA dataset.SettingThe study was conducted at the National Cancer Center, Cancer Hospital, Chinese Academy of Medical Sciences, and Peking Union Medical College.PatientsA total of 182 postmenopausal breast cancer patients and 111 healthy subjects from January 2010 to August 2010 were included in the analysis. Another 702 cases with breast cancer were retrieved from The Cancer Genome Atlas (TCGA) database for subsequent analysis.Main Outcome MeasureSerum circulating estradiol and leptin level.ResultsThe level of estradiol was significantly higher (P<0.001) but the level of leptin had no significant difference (P = 0.764) in postmenopausal breast cancer patients compared with healthy subjects. The level of estradiol and leptin was not significantly different between estrogen receptor (ER) positive and ER-negative groups (P>0.05). Estradiol was significantly correlated with tumor T stage (P = 0.002) and leptin was significantly associated with perineural invasion (P = 0.014). In addition, the disease-free survival of patients with a high level of estradiol was significantly shorter (P = 0.025) but leptin tended to be a protective factor for overall survival in TCGA analysis (P = 0.038).ConclusionCirculating estradiol and leptin played important roles in the risk of postmenopausal breast cancer even in low-estrogen nations with an independent expression of ER status. High circulating estradiol was a poor prognostic factor and leptin may be a protection signal in Chinese postmenopausal patients with breast cancer.

Intestinal Microbiota in Postmenopausal Breast Cancer Patients and Controls

Background: Previous preclinical and clinical research has investigated the role of intestinal microbiota in carcinogenesis. Growing evidence exists that intestinal microbiota can influence breast cancer carcinogenesis. However, the role of intestinal microbiota in breast cancer needs to be further investigated. This study aimed to identify the microbiota differences between postmenopausal breast cancer patients and controls. Patients and methods: This prospective cohort study compared the intestinal microbiota richness, diversity, and composition in postmenopausal histologically proven ER+/HER2- breast cancer patients and postmenopausal controls. Patients scheduled for (neo)adjuvant adriamycin, cyclophosphamide (AC), and docetaxel (D), or endocrine therapy (tamoxifen) were prospectively enrolled in a multicentre cohort study in the Netherlands. Patients collected a faecal sample and completed a questionnaire before starting systemic cancer treatment. Controls, enrolled from the National Dutch Breast Cancer Screening Programme, also collected a faecal sample and completed a questionnaire. Intestinal microbiota was analysed by amplicon sequencing of the 16S rRNA V4 gene region. Results: In total, 81 postmenopausal ER+/HER2- breast cancer patients and 67 postmenopausal controls were included, resulting in 148 faecal samples. Observed species richness, Shannon index, and overall microbial community structure were not significantly different between breast cancer patients and controls. There was a significant difference in overall microbial community structure between breast cancer patients scheduled for adjuvant treatment, neoadjuvant treatment, and controls at the phylum (p = 0.042) and genus levels (p = 0.015). Dialister (p = 0.001) and its corresponding family Veillonellaceae (p = 0.001) were higher in patients scheduled for adjuvant treatment, compared to patients scheduled for neoadjuvant treatment. Additional sensitivity analysis to correct for the potential confounding effect of prophylactic antibiotic use, indicated no differences in microbial community structure between patients scheduled for neoadjuvant systemic treatment, adjuvant systemic treatment, and controls at the phylum (p = 0.471) and genus levels (p = 0.124). Conclusions: Intestinal microbiota richness, diversity, and composition are not different between postmenopausal breast cancer patients and controls. The increased relative abundance of Dialister and Veillonellaceae was observed in breast cancer patients scheduled for adjuvant treatment, which might be caused by a relative decrease in other bacteria due to prophylactic antibiotic administration rather than an absolute increase.

An epigenetic aging analysis of randomized metformin and weight loss interventions in overweight postmenopausal breast cancer survivors

Metformin and weight loss relationships with epigenetic age measures—biological aging biomarkers—remain understudied. We performed a post-hoc analysis of a randomized controlled trial among overweight/obese breast cancer survivors (N = 192) assigned to metformin, placebo, weight loss with metformin, or weight loss with placebo interventions for 6 months. Epigenetic age was correlated with chronological age (r = 0.20–0.86; P < 0.005). However, no significant epigenetic aging associations were observed by intervention arms. Consistent with published reports in non-cancer patients, 6 months of metformin therapy may be inadequate to observe expected epigenetic age deceleration. Longer duration studies are needed to better characterize these relationships.Trial Registration: Registry Name: ClincialTrials.Gov.Registration Number: NCT01302379.Date of Registration: February 2011.URL:https://clinicaltrials.gov/ct2/show/NCT01302379

Obesity in Postmenopausal Breast Cancer Patients: It Is Time to Improve Actions for a Healthier Lifestyle. The Results of a Comparison Between Two Italian Regions With Different “Presumed” Lifestyles

BackgroundAdult body fatness is a convincing risk factor for postmenopausal breast cancer. With the aim to compare the different breast cancer (BC) features in Northern and Southern Italy, we investigated the relationship between BMI and BC characteristic in two groups of patients referred in the Modena and Lecce breast units.Materials and MethodsA retrospective analysis of a continuous series of BC patients referred to the Città di Lecce Hospital and the Modena Cancer Center, from January 2019 to December 2020 was performed. We identified four groups of BMI at BC diagnosis: underweight, BMI &lt;18.5 kg/m2; normal weight, BMI ≥ 18.5–24.9 kg/m2; overweight, BMI ≥ 25.0–29.9 kg/m2; obese, BMI ≥30.0 kg/m2. BC characteristics and clinical outcomes were analyzed by the Kolmogorov-Smirnov test and Mann-Whitney U test; categorical data were compared using Pearson’s chi-square test, and dicotomic data were compared by odds ratio.ResultsNine hundred seventy-seven BC patients were included in the analysis. Overall, 470 were from Modena and 507 from Lecce. No differences were observed in the mean age of BC patients of Modena (61,42) and Lecce (62,08). No statistical differences between the two populations were shown in terms of tumor characteristics and pathological stage. Conversely, a statistical difference of BMI between the BC patients coming from Modena and Lecce (25.87 and 27.81, respectively; p = 0.000001) was found. BC patients diagnosed in Lecce at age ≥70 years had higher median BMI compared with the ones from Modena (p = 0.000002). The increased BMI in this aged population was also associated to larger tumor size (p = 0.040).ConclusionThe rate of overweight and obesity was higher in BC women living in Southern Italy, despite the presumed nutrition according to the so-called Mediterranean type dietary pattern. Unexpectedly, an increased BMI rate and a relationship with larger tumor size were found in Southern BC patients aged ≥70 years. Our findings strongly support the need for promoting a healthier lifestyle model in Italy, with the aim of reducing the rate of the obesity and, consequently, the increased risk of BC.

Clinical and Sociodemographic Risk Factors Associated With the Development of Second Primary Cancers Among Postmenopausal Breast Cancer Survivors

Introduction: Advances in breast cancer (BC) diagnosis and treatment have increased the number of long-term survivors. Consequently, survivors of primary BC are at a greater risk of developing second primary cancers (SPCs). The risk factors for SPCs among BC survivors including sociodemographic, cancer treatment, comorbidities, and other medications have not been comprehensively examined. The purpose of this study is to assess the incidence and clinicopathologic factors associated with risk of SPCs. Methods: We analyzed 170, 639 women with early-stage primary BC diagnosed between January 2000-December 2015 from the Medicare-linked Surveillance Epidemiology and End Results (SEER-Medicare) database. SPC was defined as any diagnosis of malignancy occurring within the study period and at least two months after primary BC diagnosis. Univariate analyses compared baseline characteristics between those who developed a SPC and those who did not. We evaluated the cause-specific hazard of developing a SPC in the presence of death as a competing risk.Results: Of the study cohort, 20,838 (12%) of BC survivors developed a SPC and BC was the most common SPC type (32%). The median time to SPC was 42 months. Women who were white, older, and with fewer comorbidities were more likely to develop a SPC. While statins [hazard ratio (HR) 1.060 (1.016 - 1.106)] and anti-hypertensives [HR 1.517 (1.461 – 1.575)] increased the hazard of developing a SPC, aromatase inhibitor therapy [HR 0.588 (0.542 – 0.638)] and bisphosphonates [HR 0.897 (0.848 – 0.949)] were associated with a decreased hazard of developing any SPC, including non-breast SPCs.Conclusion: Our study shows that specific clinical factors including type of cancer treatment, medications, and comorbidities are associated with increased risk for the development of SPCs among older BC survivors. These results can increase patient and clinician awareness, target cancer screening among BC survivors, as well as developing risk-adapted management strategies.