The Obesity Paradox in Cancer, Tumor Immunology, and Immunotherapy: Potential Therapeutic Implications in Triple Negative Breast Cancer

Predicting doxorubicin-induced cardiotoxicity in breast cancer: leveraging machine learning with synthetic data

Doxorubicin (DOXO) is a primary treatment for breast cancer but can cause cardiotoxicity in over 25% of patients within the first year post-chemotherapy. Recognizing at-risk patients before DOXO initiation offers pathways for alternative treatments or early protective actions. We analyzed data from 78 Brazilian breast cancer patients, with 34.6% developing cardiotoxicity within a year of their final DOXO dose. To address the limited sample size, we utilized the DAS (Data Augmentation and Smoothing) method, creating 4892 synthetic samples that exhibited high statistics fidelity to the original data. By integrating routine blood biomarkers (C-Reactive protein, total cholesterol, LDL-c, HDL-c, hematocrit, and hemoglobin) and two clinical measures (weighted smoking status and body mass index), our model achieved an AUROC of 0.85±0.10, a sensitivity of 0.89, and a specificity of 0.69, positioning it as a potential screening instrument. Notably, DAS outperformed the established methods, Adaptive Synthetic Sampling (ADASYN), Synthetic Minority Over-Sampling Technique (SMOTE), and Synthetic Data Vault (SDV), underscoring its promise for medical synthetic data generation and pioneering a cardiotoxicity prediction model specifically for DOXO.

Impact of obesity on pathological complete remission in early stage breast cancer patients after neoadjuvant chemotherapy: a retrospective study from a German University breast center

PURPOSE

Breast cancer is a primary cause of cancer-related death among women worldwide. Neoadjuvant chemotherapy (NACT) is a cornerstone treatment for locally advanced, non-metastatic breast cancer. Achieving pathological complete response (pCR) is often used as a surrogate marker for long-term outcomes. This study examines the impact of obesity, defined by a body mass index (BMI) over 30 kg/m2, on achieving pCR in patients with early stage breast cancer (eBC) undergoing NACT.

METHODS

A retrospective analysis was conducted on patients with eBC treated with NACT at the University of Tübingen. The primary objective was to assess the impact of obesity on achieving pCR. Logistic regression analysis was used to determine the association between pre-treatment BMI and pCR, adjusting for covariates such as age, tumor stage, grading, and chemotherapy intensity.

RESULTS

The study included 325 patients, with 24% classified as obese. While the univariate logistic regression analysis showed no significant impact of obesity on the odds ratio of achieving pCR, the multivariate analysis, accounting for covariates, demonstrated that obese patients had a significantly higher likelihood of achieving pCR.

CONCLUSION

In this retrospective study, obesity significantly affected the likelihood of achieving pCR in patients with eBC cancer undergoing NACT after adjusting for covariates. While obesity is a known risk factor for breast cancer development and progression, its impact on the efficacy of NACT in terms of achieving pCR was positive in our study. These findings contribute to the ongoing debate in the literature, though the retrospective design and potential uncontrolled factors should be considered.

Calcium Channel Blocker Lacidipine Promotes Antitumor Immunity by Reprogramming Tryptophan Metabolism

Dysfunction of calcium channels is involved in the development and progression of some cancers. However, it remains unclear the role of calcium channel inhibitors in tumor immunomodulation. Here, calcium channel blocker lacidipine is identified to potently inhibit the enzymatic activity and expression of indoleamine 2,3-dioxygenase 1 (IDO1), a rate-limiting enzyme in tryptophan metabolism. Lacidipine activates effector T cells and incapacitates regulatory T cells (Tregs) to augment the anti-tumor effect of chemotherapeutic agents in breast cancer by converting immunologically "cold" into "hot" tumors. Mechanistically, lacidipine targets calcium channels (CaV1.2/1.3) to inhibit Pyk2-JAK1-calmodulin complex-mediated IDO1 transcription suppression, which suppresses the kynurenine pathway and maintains the total nicotinamide adenine dinucleotide (NAD) pool by regulating NAD biosynthesis. These results reveal a new function of calcium channels in IDO1-mediated tryptophan metabolism in tumor immunity and warrant further development of lacidipine for the metabolic immunotherapy in breast cancer.

The effect of body mass index at diagnosis on survival of patients with squamous cell head and neck carcinoma

The aim of this study is to investigate the prognostic role of body mass index (BMI) on survival from head and neck cancer (HNC). We performed a pooled analysis of studies included in the International Head and Neck Cancer Epidemiology consortium. We used Cox proportional hazards models to estimate the adjusted hazard ratios (HR) for overall survival and HNC-specific survival, and we stratified the results according to cancer site. The study included 10,177 patients from 10 studies worldwide. Underweight patients had lower overall survival (HR=1.69, 95% CI: 1.31-2.19) respect to those having normal weight with consistent results across the HNC sites. Overweight and obese patients had a favourable HNC-specific survival (HR=0.77 (95% CI: 0.70-0.84) and HR=0.80 (95% CI: 0.76-0.84), respectively), with heterogenous results according to HNC site. Our findings show that high BMI values at cancer diagnosis improved the survival rates in patients with HNC, especially among smokers. This association may be explained by residual confounding, reverse causation, and collider stratification bias, but may also suggest that a nutritional reserve may help patients survive HNC cancer.

Systemic Inflammation, the Peripheral Blood Transcriptome, and Primary Melanoma

Peripheral blood transcriptomes from 383 patients with newly diagnosed melanoma were subjected to differential gene expression analysis. The hypotheses were that impaired systemic immunity is associated with poorer prognosis (thicker tumors and fewer tumor-infiltrating lymphocytes) and evidence of systemic inflammation (high-sensitivity CRP and fibrinogen levels). Higher fibrinogen levels were associated with thicker primary tumors. In single-gene analysis, high-sensitivity CRP levels were significantly associated with higher blood CD274 expression (coding for PD-L1), but each was independently prognostic, with high-sensitivity CRP associated with increased mortality and higher CD274 protective, independent of age. Pathway analysis identified downregulation of immune cell signaling pathways in the blood of people with thicker tumors and notable upregulation of signal transducer and activator of transcription 1 gene STAT1 in people with brisk tumor-infiltrating lymphocytes. Transcriptomic data provided evidence for increased NF-kB signaling with higher inflammatory markers but with reduction in expression of HLA class II molecules and higher CD274, suggesting that aberrant systemic inflammation is a significant mediator of reduced immune function in melanoma. In summary, transcriptomic data revealed evidence of reduced immune function in patients with thicker tumors and fewer tumor-infiltrating lymphocytes at diagnosis. Inflammatory markers were associated with thicker primaries and independently with death from melanoma, suggesting that systemic inflammation contributes to that reduced immune function.

IMMUNE AND MOLECULAR CORRELATES OF RESPONSE TO IMMUNOTHERAPY REVEALED BY BRAIN-METASTATIC MELANOMA MODELS

Despite the promising results of immune checkpoint blockade (ICB) therapy, outcomes for patients with brain metastasis (BrM) remain poor. Identifying resistance mechanisms has been hindered by limited access to patient samples and relevant preclinical models. Here, we developed two mouse melanoma BrM models that recapitulate the disparate responses to ICB seen in patients. We demonstrate that these models capture the cellular and molecular complexity of human disease and reveal key factors shaping the tumor microenvironment and influencing ICB response. BR1-responsive tumor cells express inflammatory programs that polarize microglia into reactive states, eliciting robust T cell recruitment. In contrast, BR3-resistant melanoma cells are enriched in neurological programs and exploit tolerance mechanisms to maintain microglia homeostasis and limit T cell infiltration. In humans, BR1 and BR3 expression signatures correlate positively or negatively with T cell infiltration and BrM patient outcomes, respectively. Our study provides clinically relevant models and uncovers mechanistic insights into BrM ICB responses, offering potential biomarkers and therapeutic targets to improve therapy efficacy.

Impact of Body Mass Index on All-Cause Mortality in Adults: A Systematic Review and Meta-Analysis

Background: Obesity is a risk factor for many diseases, diagnosed by calculating body mass index (BMI). Methods: To find an association between BMI and mortality in adults, we searched PubMed for articles published in the 21st century. Our review included 82 original studies, comprising 2.7 million patients and 23.4 million patient years. Results: The meta-analysis showed a U-shaped relationship between BMI and all-cause mortality risk, with the lowest mortality in the BMI range of 25-30 kg/m2. Subgroup analysis showed a J-shaped relationship, with greater risk in the highest BMI range (>35 kg/m2). Among the elderly, BMI values <20 kg/m2 were associated with the highest risk. Among diabetic patients, a U-shaped relationship was noticed, again with the highest risk in the lowest (<20 kg/m2) and highest BMI range (>35 kg/m2). Among patients with cardiovascular disease, the risk increased with BMI values <25 kg/m2 but did not noticeably change for BMI exceeding that value. Among cancer patients, the relationship was less pronounced than in other subgroups, with a slightly higher risk (>35 kg/m2). Conclusions: Our results show that the lowest mortality is observed among patients with BMI 25-30 kg/m2. Reduction of body mass should not be a universal recommendation in clinical practice, but it should be individualized.

Prenatal airborne polycyclic aromatic hydrocarbon exposure, altered regulation of peroxisome proliferator-activated receptor gamma (Ppar)γ, and links with mammary cancer

Environmental exposure to polycyclic aromatic hydrocarbons (PAH) has been shown to be associated with chronic disease outcomes through multiple mechanisms including altered regulation of the transcription factor peroxisome proliferator-activated receptor gamma (Ppar) γ. Because PAH exposure and Pparγ each have been associated with mammary cancer, we asked whether PAH would induce altered regulation of Pparγ in mammary tissue, and whether this association may underlie the association between PAH and mammary cancer. Pregnant mice were exposed to aerosolized PAH at proportions that mimic equivalent human exposures in New York City air. We hypothesized that prenatal PAH exposure would alter Pparγ DNA methylation and gene expression and induce the epithelial to mesenchymal transition (EMT) in mammary tissue of offspring (F1) and grandoffspring (F2) mice. We also hypothesized that altered regulation of Pparγ in mammary tissue would associate with biomarkers of EMT, and examined associations with whole body weight. We found that prenatal PAH exposure lowered Pparγ mammary tissue methylation among grandoffspring mice at postnatal day (PND) 28. However, PAH exposure did not associate with altered Pparγ gene expression or consistently with biomarkers of EMT. Finally, lower Pparγ methylation, but not gene expression, was associated with higher body weight among offspring and grandoffspring mice at PND28 and PND60. Findings suggest additional evidence of multi-generational adverse epigenetic effects of prenatal PAH exposure among grandoffspring mice.

The Role of Obesity in Breast Cancer Pathogenesis

Research has shown that obesity increases the risk for type 2 diabetes mellitus (Type 2 DM) by promoting insulin resistance, increases serum estrogen levels by the upregulation of aromatase, and promotes the release of reactive oxygen species (ROS) by macrophages. Increased circulating glucose has been shown to activate mammalian target of rapamycin (mTOR), a significant signaling pathway in breast cancer pathogenesis. Estrogen plays an instrumental role in estrogen-receptor-positive breast cancers. The role of ROS in breast cancer warrants continued investigation, in relation to both pathogenesis and treatment of breast cancer. We aim to review the role of obesity in breast cancer pathogenesis and novel therapies mediating obesity-associated breast cancer development. We explore the association between body mass index (BMI) and breast cancer incidence and the mechanisms by which oxidative stress modulates breast cancer pathogenesis. We discuss the role of glutathione, a ubiquitous antioxidant, in breast cancer therapy. Lastly, we review breast cancer therapies targeting mTOR signaling, leptin signaling, blood sugar reduction, and novel immunotherapy targets.

Hypoxia: syndicating triple negative breast cancer against various therapeutic regimens

Triple-negative breast cancer (TNBC) is one of the deadliest subtypes of breast cancer (BC) for its high aggressiveness, heterogeneity, and hypoxic nature. Based on biological and clinical observations the TNBC related mortality is very high worldwide. Emerging studies have clearly demonstrated that hypoxia regulates the critical metabolic, developmental, and survival pathways in TNBC, which include glycolysis and angiogenesis. Alterations to these pathways accelerate the cancer stem cells (CSCs) enrichment and immune escape, which further lead to tumor invasion, migration, and metastasis. Beside this, hypoxia also manipulates the epigenetic plasticity and DNA damage response (DDR) to syndicate TNBC survival and its progression. Hypoxia fundamentally creates the low oxygen condition responsible for the alteration in Hypoxia-Inducible Factor-1alpha (HIF-1α) signaling within the tumor microenvironment, allowing tumors to survive and making them resistant to various therapies. Therefore, there is an urgent need for society to establish target-based therapies that overcome the resistance and limitations of the current treatment plan for TNBC. In this review article, we have thoroughly discussed the plausible significance of HIF-1α as a target in various therapeutic regimens such as chemotherapy, radiotherapy, immunotherapy, anti-angiogenic therapy, adjuvant therapy photodynamic therapy, adoptive cell therapy, combination therapies, antibody drug conjugates and cancer vaccines. Further, we also reviewed here the intrinsic mechanism and existing issues in targeting HIF-1α while improvising the current therapeutic strategies. This review highlights and discusses the future perspectives and the major alternatives to overcome TNBC resistance by targeting hypoxia-induced signaling.

Metabolic Dysregulation Explains the Diverse Impacts of Obesity in Males and Females with Gastrointestinal Cancers

The prevalence of obesity, defined as the body mass index (BMI) ≥ 30 kg/m2, has reached epidemic levels. Obesity is associated with an increased risk of various cancers, including gastrointestinal ones. Recent evidence has suggested that obesity disproportionately impacts males and females with cancer, resulting in varied transcriptional and metabolic dysregulation. This study aimed to elucidate the differences in the metabolic milieu of adenocarcinomas of the gastrointestinal (GI) tract both related and unrelated to sex in obesity. To demonstrate these obesity and sex-related effects, we utilized three primary data sources: serum metabolomics from obese and non-obese patients assessed via the Biocrates MxP Quant 500 mass spectrometry-based kit, the ORIEN tumor RNA-sequencing data for all adenocarcinoma cases to assess the impacts of obesity, and publicly available TCGA transcriptional analysis to assess GI cancers and sex-related differences in GI cancers specifically. We applied and integrated our unique transcriptional metabolic pipeline in combination with our metabolomics data to reveal how obesity and sex can dictate differential metabolism in patients. Differentially expressed genes (DEG) analysis of ORIEN obese adenocarcinoma as compared to normal-weight adenocarcinoma patients resulted in large-scale transcriptional reprogramming (4029 DEGs, adj. p < 0.05 and |logFC| > 0.58). Gene Set Enrichment and metabolic pipeline analysis showed genes enriched for pathways relating to immunity (inflammation, and CD40 signaling, among others) and metabolism. Specifically, we found alterations to steroid metabolism and tryptophan/kynurenine metabolism in obese patients, both of which are highly associated with disease severity and immune cell dysfunction. These findings were further confirmed using the TCGA colorectal adenocarcinoma (CRC) and esophageal adenocarcinoma (ESCA) data, which showed similar patterns of increased tryptophan catabolism for kynurenine production in obese patients. These patients further showed disparate alterations between males and females when comparing obese to non-obese patient populations. Alterations to immune and metabolic pathways were validated in six patients (two obese and four normal weight) via CD8+/CD4+ peripheral blood mononuclear cell RNA-sequencing and paired serum metabolomics, which showed differential kynurenine and lipid metabolism, which corresponded with altered T-cell transcriptome in obese populations. Overall, obesity is associated with differential transcriptional and metabolic programs in various disease sites. Further, these alterations, such as kynurenine and tryptophan metabolism, which impact both metabolism and immune phenotype, vary with sex and obesity together. This study warrants further in-depth investigation into obesity and sex-related alterations in cancers that may better define biomarkers of response to immunotherapy.

CEBP-β and PLK1 as Potential Mediators of the Breast Cancer/Obesity Crosstalk: In Vitro and In Silico Analyses

Over the last two decades, obesity has reached pandemic proportions in several countries, and expanding evidence is showing its contribution to several types of malignancies, including breast cancer (BC). The conditioned medium (CM) from mature adipocytes contains a complex of secretes that may mimic the obesity condition in studies on BC cell lines conducted in vitro. Here, we report a transcriptomic analysis on MCF-7 BC cells exposed to adipocyte-derived CM and focus on the predictive functional relevance that CM-affected pathways/processes and related biomarkers (BMs) may have in BC response to obesity. CM was demonstrated to increase cell proliferation, motility and invasion as well as broadly alter the transcript profiles of MCF-7 cells by significantly modulating 364 genes. Bioinformatic functional analyses unraveled the presence of five highly relevant central hubs in the direct interaction networks (DIN), and Kaplan-Meier analysis sorted the CCAAT/enhancer binding protein beta (CEBP-β) and serine/threonine-protein kinase PLK1 (PLK1) as clinically significant biomarkers in BC. Indeed, CEBP-β and PLK1 negatively correlated with BC overall survival and were up-regulated by adipocyte-derived CM. In addition to their known involvement in cell proliferation and tumor progression, our work suggests them as a possible "deus ex machina" in BC response to fat tissue humoral products in obese women.

Impact of Body Mass Index on Pathological Response after Neoadjuvant Chemotherapy: Results from the I-SPY 2 trial

Purpose

Increased body mass index (BMI) has been associated with poor outcomes in women with breast cancer. We evaluated the association between BMI and pathological complete response (pCR) in the I-SPY 2 trial.

Methods

978 patientsenrolled in the I-SPY 2 trial 3/2010-11/2016 and had a recorded baseline BMI prior to treatment were included in the analysis. Tumor subtypes were defined by hormone receptor and HER2 status. Pretreatment BMI was categorized as obese (BMI≥30 kg/m2), overweight (25≤BMI < 30 kg/m2), and normal/underweight (< 25 kg/m2). pCR was defined as elimination of detectable invasive cancer in the breast and lymph nodes (ypT0/Tis and ypN0) at the time of surgery. Logistic regression analysis was used to determine associations between BMI and pCR. Event-free survival (EFS) and overall survival (OS) between different BMI categories were examined using Cox proportional hazards regression.

Results

The median age in the study population was 49 years. pCR rates were 32.8% in normal/underweight, 31.4% in overweight, and 32.5% in obese patients. In univariable analysis, there was no significant difference in pCR with BMI. In multivariable analysis adjusted for race/ethnicity, age, menopausal status, breast cancer subtype, and clinical stage, there was no significant difference in pCR after neoadjuvant chemotherapy for obese compared with normal/underweight patients (OR = 1.1, 95% CI: 0.68-1.63, p = 0.83), and for overweight compared with normal/underweight (OR = 1, 95% CI: 0.64-1.47, p = 0.88). We tested for potential interaction between BMI and breast cancer subtype; however, the interaction was not significant in the multivariable model (p = 0.09). Multivariate Cox regression showed there was no difference in EFS (p = 0.81) or OS (p = 0.52) between obese, overweight, and normal/underweight breast cancer patients with a median follow-up time of 3.8 years.

Conclusions

We found no difference in pCR rates by BMI with actual body weight based neoadjuvant chemotherapy in this biologically high-risk breast cancer population in the I-SPY2 trial.

Obesity and cancer: focus on leptin

Over the past decades, obesity has grown to epidemic proportions worldwide. It has been associated with an increased risk for different types of cancer. In addition, obesity has been associated with a poor prognosis, an increased risk of metastasis and mortality, and resistance to anti-cancer therapies. The pathophysiological mechanisms underlying the obesity-cancer connection have not yet been fully elucidated. However, this connection could result, at least in part, from the action of adipokines, whose levels are increased in obesity. Among these adipokines, evidence suggests leptin's critical role in linking obesity to cancer. In this review, we first summarize the current state of the literature regarding the implication of leptin in tumorigenic processes. Next, we focus on the effects of leptin on the anti-tumor immune response. Then, we discuss the influence of leptin on the efficiency of antineoplastic treatments and the development of tumor resistance. Finally, we highlight the use of leptin as a potential target for the prevention and treatment of cancer.

Obesity contributes to hepatocellular carcinoma development via immunosuppressive microenvironment remodeling

It is generally recognized that the initiation of obesity-related hepatocellular carcinoma (HCC) is closely associated with hepatic inflammation. However, the paradoxical role of inflammation in the initiation and progression of HCC is highlighted by the fact that the inflammatory HCC is accompanied by significant immune effector cells infiltration compared to non-inflammatory HCC and HCC with enhanced immune response exhibits better survival. Importantly, the cancer progression has been primarily attributed to the immunosuppression, which can also be induced by obesity. Furthermore, the increased risk of viral infection and thus viral-HCC in obese individuals supports the view that obesity contributes to HCC via immunosuppression. Here, we have reviewed the various mechanisms responsible for obesity-induced tumor immune microenvironment and immunosuppression in obesity-related HCC. We highlight that the obesity-induced immunosuppression originates from lipid disorder as well as metabolic reprogramming and propose potential therapeutic strategy for HCC based on the current success of immunotherapy.

The Challenges of Treating Patients with Breast Cancer and Obesity

Obesity is defined as a body mass index (BMI) of 30 kg/m2 or more and is associated with worse outcomes in patients with breast cancer, resulting in an increased incidence of breast cancer, recurrence, and death. The incidence of obesity is increasing, with almost half of all individuals in the United States classified as obese. Patients with obesity present with unique pharmacokinetics and physiology and are at increased risk of developing diabetes mellitus and cardiovascular disease, which leads to specific challenges when treating these patients. The aim of this review is to summarize the impact of obesity on the efficacy and toxicity of systemic therapies used for breast cancer patients, describe the molecular mechanisms through which obesity can affect systemic therapies, outline the existing American Society of Clinical Oncology (ASCO) guidelines for treating patients with cancer and obesity, and highlight additional clinical considerations for treating patients with obesity and breast cancer. We conclude that further research on the biological mechanisms underlying the obesity-breast cancer link may offer new treatment strategies, and clinicals trials that focus on the treatment and outcomes of patients with obesity and all stages of breast cancer are needed to inform future treatment guidelines.

The association between body mass index and efficacy of pembrolizumab as second-line therapy in patients with recurrent/metastatic head and neck squamous cell carcinoma

BACKGROUND

Recent evidence suggested a potential correlation between BMI and the efficacy of immune checkpoint inhibitors in cancer patients. This study aimed to evaluate the prognostic value of the body mass index (BMI) in recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC) patients treat with pembrolizumab.

METHODS

The current retrospective cohort study enrolled 49 R/M HNSCC patients underwent at least one cycle of pembrolizumab as second-line treatment from June 2018 to October 2020. Survival analysis of immunotherapy prognosis and risk factor analysis of age, gender, BMI, ECOG-PS, CPS, rT-stage, tumor site, and tube feeding.

RESULTS

Among the 49 patients, the BMI at the time of immunotherapy ranged from 14.5 to 32.0 kg/m² . The Kaplan-Meier analysis showed that the BMI was significantly correlated with overall survival time (OS, p = 0.0007) and progression-free survival time (PFS, p = 0.0012). BMI, gender, prior treatment, serum albumin level, ECOG-PS, CPS and rT-stage were analyzed in multivariate Cox regression model analysis after adjusted for potential confounding clinical variables. Patients with underweight (OS:HR = 6.862, 95% CI:1.566-30.064, p = 0.011; PFS:HR = 5.672, 95% CI:1.364-23.586, p = 0.017);ECOG≥2 (OS:HR = 0.250, 95% CI:0.086-0.731, p = 0.011;PFS:HR = 0.284, 95% CI:0.101-0.805, p = 0.018); CPS <1(OS: HR = 4.34, 95% CI:1.271-15.464, p = 0.019; PFS:HR = 3.859, 95% CI:1.180-12.618, p = 0.025) and rT4-stage(OS:HR = 4.380, 95% CI:1.452-13.209, p = 0.009;PFS: HR = 3.799, 95% CI:1.240-11.638, p = 0.019) suffered higher risk of mortality.

CONCLUSIONS

The BMI at the time of clinical diagnosis was showed to be an independent predictive factor for R/M HNSCC patients receiving pembrolizumab. Compared with normal weight patients, underweight patients have worse clinical prognosis.

Role of FABP5 in T Cell Lipid Metabolism and Function in the Tumor Microenvironment

To evade immune surveillance, tumors develop a hostile microenvironment that inhibits anti-tumor immunity. Recent immunotherapy breakthroughs that target the reinvigoration of tumor-infiltrating T lymphocytes (TIL) have led to unprecedented success in treating some cancers that are resistant to conventional therapy, suggesting that T cells play a pivotal role in anti-tumor immunity. In the hostile tumor microenvironment (TME), activated T cells are known to mainly rely on aerobic glycolysis to facilitate their proliferation and anti-tumor function. However, TILs usually exhibit an exhausted phenotype and impaired anti-tumor activity due to the limited availability of key nutrients (e.g., glucose) in the TME. Given that different T cell subsets have unique metabolic pathways which determine their effector function, this review introduces our current understanding of T cell development, activation signals and metabolic pathways. Moreover, emerging evidence suggests that fatty acid binding protein 5 (FABP5) expression in T cells regulates T cell lipid metabolism and function. We highlight how FABP5 regulates fatty acid uptake and oxidation, thus shaping the survival and function of different T cell subsets in the TME.

Two-sided roles of adipose tissue: Rethinking the obesity paradox in various human diseases from a new perspective

Overweight and obesity, as a result of excess fat accumulation, have become a worldwide public health issue. Recent studies have shown that obesity is closely related to many human diseases, such as cancer, cardiovascular diseases, and type 2 diabetes mellitus, in which adipose tissue plays a dual role. In addition to thermal and mechanical insulation and a critical role in energy storage and heat production, adipose tissue is also a highly plastic endocrine and signaling organ that secretes multiple bioactive molecules for inter-organ crosstalk. The phenotypic and biological changes of adipose tissue under pathological conditions, especially in obesity, increase the challenge of deciphering the positive or negative effects of adipose tissue in disease. Despite numerous studies on obesity and adipose tissue, the ambiguous role of adipose tissue on specific organs or tissues in different diseases is not fully understood, and the definite mechanisms remain obscure. In this review, we first summarize the basic biological characteristics of adipose tissue in the physiological state and the abnormal remodeling of adipose tissue during obesity. We then discuss the complex and disparate effects of obesity on various human diseases, with a particular focus on the dual roles and underlying mechanisms of adipose tissue, a quintessential player in obesity, in this process. More importantly, rethinking the causes of the "obesity paradox" phenomenon in diseases from the perspective of adipose homeostasis and dysfunction provides a novel strategy for disease treatment by intervening in fat function.

Obesity and Risk for Lymphoma: Possible Role of Leptin

Obesity, which is considered a pandemic due to its high prevalence, is a risk factor for many types of cancers, including lymphoma, through a variety of mechanisms by promoting an inflammatory state. Specifically, over the last few decades, obesity has been suggested not only to increase the risk of lymphoma but also to be associated with poor clinical outcomes and worse responses to different treatments for those diseases. Within the extensive range of proinflammatory mediators that adipose tissue releases, leptin has been demonstrated to be a key adipokine due to its pleotropic effects in many physiological systems and diseases. In this sense, different studies have analyzed leptin levels and leptin/leptin receptor expressions as a probable bridge between obesity and lymphomas. Since both obesity and lymphomas are prevalent pathophysiological conditions worldwide and their incidences have increased over the last few years, here we review the possible role of leptin as a promising proinflammatory mediator promoting lymphomas.

Immunogenic analysis of epitope-based vaccine candidate induced by photodynamic therapy in MDA-MB-231 triple-negative breast cancer cells

BACKGROUND

Photodynamic therapy (PDT) is used to treat tumors through selective cytotoxic effects. PDT induces damage-associated molecular patterns (DAMPs) expression, which can cause an immunogenic death cell (IDC). In this study we identified potential immunogenic epitopes generated by PDT on triple-negative breast cancer cell line (MDA-MB-231).

METHODS

MDA-MB-231 cells were exposed to PDT using ALA (160 µg/mL)/630 nm at 8 J/cm². Membrane proteins were extracted and separated by 2D PAGE. Proteins overexpressed were identified by LC-MS/MS and analyzed in silico through a peptide-HLA docking in order to identify the epitopes with more immunogenicity and antigenicity properties, as well as lower allergenicity and toxicity activity. The selected peptides were evaluated in response to macrophage activation and cytokine release by flow cytometry.

RESULTS

Differential proteins were overexpressed in the cells treated with PDT. A group of 16 peptides were identified from them, established in a rigorous selection by measuring antigenicity, immunogenicity, allergenicity, and toxicity in silico. The final selection was based on molecular dynamics, where 2 peptides showed the highest stability regarding to the RMSD value. These peptides were obtained from the proteins calreticulin and HSP90. The cytokine analysis evidenced macrophage activation by the releasing of TNF.

CONCLUSION

Two peptides were identified from calreticulin and HSP90; proteins induced by PDT in MDA-MB-231 cells. Both epitopes showed immunogenic potential as a peptide-based vaccine for triple-negative breast cancer.

Insight on the Role of Leptin: A Bridge from Obesity to Breast Cancer

Leptin is a peptide hormone, mainly known for its role as a mediator of adipose tissue endocrine functions, such as appetite control and energy homeostasis. In addition, leptin signaling is involved in several physiological processes as modulation of innate and adaptive immune responses and regulation of sex hormone levels. When adipose tissue expands, an imbalance of adipokines secretion may occur and increasing leptin levels contribute to promoting a chronic inflammatory state, which is largely acknowledged as a hallmark of cancer. Indeed, upon binding its receptor (LEPR), leptin activates several oncogenic pathways, such as JAK/STAT, MAPK, and PI3K/AKT, and seems to affect cancer immune response by inducing a proinflammatory immune polarization and eventually enhancing T-cell exhaustion. In particular, obesity-associated hyperleptinemia has been related to breast cancer risk development, although the underlying mechanism is yet to be completely clarified and needs to be deemed in light of multiple variables, such as menopausal state and immune response. The aim of this review is to provide an overview of the potential role of leptin as a bridge between obesity and breast cancer and to establish the physio-pathological basis of the linkage between these major health concerns in order to identify appropriate and novel therapeutic strategies to adopt in daily clinical practice.

Obesity accelerates immune evasion of non-small cell lung carcinoma via TFEB-dependent upregulation of Siglec-15 and glycolytic reprogramming

Although obesity contributes to tumor incidence and progression in various cancers, whether obesity impacts the tumor microenvironment (TME) of non-small cell lung cancer (NSCLC) remains largely under-explored. We generated NSCLC xenograft model in diet-induced obese mice and identified that TFEB is critical to accelerate obesity-related NSCLC progression with mimic intrinsic functions on tumor biology. Mechanically, TFEB binds directly to Siglec-15 promoter to upregulate Siglec-15 expression and binds to Hk2 and Ldha promoters to enhance glycolytic flux in NSCLC cells, which restrain the expansion and cytotoxic function of CD8⁺ T cells while maintain suppressive Treg cells in TME, jointly promoting immune evasion of NSCLC cells in obesity. Blocking tumor TFEB improves the therapeutic efficiency of anti-PD-1 in obese mice. Altogether, our data identify essential roles of TFEB in remodeling immunosuppressive TME and promoting NSCLC development in obesity, providing scientific rational for TFEB as a potential biomarker to predict immune checkpoint blockade efficiency in obese NSCLC patients.

Adipose tissue-to-breast cancer crosstalk: Comprehensive insights

The review focuses on mechanistic evidence for the link between obesity and breast cancer. According to the IARC study, there is sufficient evidence that obesity is closely related to a variety of cancers. Among them, breast cancer is particularly disturbed by adipose tissue due to the unique histological structure of the breast. The review introduces the relationship between obesity and breast cancer from two aspects, including factors that promote tumorigenesis or metastasis. We summarize alterations in adipokines and metabolic pathways that contribute to breast cancer development. Breast cancer metastasis is closely related to obesity-induced pro-inflammatory microenvironment, adipose stem cells, and miRNAs. Based on the mechanism by which obesity causes breast cancer, we list possible therapeutic directions, including reducing the risk of breast cancer and inhibiting the progression of breast cancer. We also discussed the risk of autologous breast remodeling and fat transplantation. Finally, the causes of the obesity paradox and the function of enhancing immunity are discussed. Evaluating the balance between obesity-induced inflammation and enhanced immunity warrants further study.

Breast cancer microenvironment and obesity: challenges for therapy

Women with obesity who develop breast cancer have a worsened prognosis with diminished survival rates and increased rates of metastasis. Obesity is also associated with decreased breast cancer response to endocrine and chemotherapeutic treatments. Studies utilizing multiple in vivo models of obesity as well as human breast tumors have enhanced our understanding of how obesity alters the breast tumor microenvironment. Changes in the complement and function of adipocytes, adipose-derived stromal cells, immune cells, and endothelial cells and remodeling of the extracellular matrix all contribute to the rapid growth of breast tumors in the context of obesity. Interactions of these cells enhance secretion of cytokines and adipokines as well as local levels of estrogen within the breast tumor microenvironment that promote resistance to multiple therapies. In this review, we will discuss our current understanding of the impact of obesity on the breast tumor microenvironment, how obesity-induced changes in cellular interactions promote resistance to breast cancer treatments, and areas for development of treatment interventions for breast cancer patients with obesity.

The role of obesity and bariatric surgery-induced weight loss in breast cancer

Obesity is a complex metabolic condition considered a worldwide public health crisis, and a deeper mechanistic understanding of obesity-associated diseases is urgently needed. Obesity comorbidities include many associated cancers and are estimated to account for 20% of female cancer deaths in the USA. Breast cancer, in particular, is associated with obesity and is the focus of this review. The exact causal links between obesity and breast cancer remain unclear. Still, interactions have emerged between body mass index, tumor molecular subtype, genetic background, and environmental factors that strongly suggest obesity influences the risk and progression of certain breast cancers. Supportive preclinical research uses various diet-induced obesity models to demonstrate that weight loss, via dietary interventions or changes in energy expenditure, reduces the onset or progression of breast cancers. Ongoing and future studies are now aimed at elucidating the underpinning mechanisms behind weight-loss-driven observations to improve therapy and outcomes in patients with breast cancer and reduce risk. This review aims to summarize the rapidly emerging literature on obesity and weight loss strategies with a focused discussion of bariatric surgery in both clinical and preclinical studies detailing the complex interactions between metabolism, immune response, and immunotherapy in the setting of obesity and breast cancer.

Response to immune checkpoint blockade improved in pre-clinical model of breast cancer after bariatric surgery

Bariatric surgery is a sustainable weight loss approach, including vertical sleeve gastrectomy (VSG). Obesity exacerbates tumor growth, while diet-induced weight loss impairs progression. It remains unknown how bariatric surgery-induced weight loss impacts cancer progression or alters response to therapy. Using a pre-clinical model of obesity followed by VSG or diet-induced weight loss, breast cancer progression and immune checkpoint blockade therapy were investigated. Weight loss by VSG or weight-matched dietary intervention before tumor engraftment protected against obesity-exacerbated tumor progression. However, VSG was not as effective as diet in reducing tumor burden despite achieving similar weight and adiposity loss. Leptin did not associate with changes in tumor burden; however, circulating IL-6 was elevated in VSG mice. Uniquely, VSG tumors displayed elevated inflammation and immune checkpoint ligand PD-L1+ myeloid and non-immune cells. VSG tumors also had reduced T lymphocytes and markers of cytolysis, suggesting an ineffective anti-tumor microenvironment which prompted investigation of immune checkpoint blockade. While obese mice were resistant to immune checkpoint blockade, anti-PD-L1 potently impaired tumor progression after VSG through improved anti-tumor immunity. Thus, in formerly obese mice, surgical weight loss followed by immunotherapy reduced breast cancer burden. Finally, we compared transcriptomic changes in adipose tissue after bariatric surgery from patients and mouse models. A conserved bariatric surgery-associated weight loss signature (BSAS) was identified which significantly associated with decreased tumor volume. Findings demonstrate conserved impacts of obesity and bariatric surgery-induced weight loss pathways associated with breast cancer progression.

As the number of people classified as obese rises globally, so do obesity-related health risks. Studies show that people diagnosed with obesity have inflammation that contributes to tumor growth and their immune system is worse at detecting cancer cells. But weight loss is not currently used as a strategy for preventing or treating cancer.

Surgical procedures for weight loss, also known as ‘bariatric surgeries’, are becoming increasingly popular. Recent studies have shown that individuals who lose weight after these treatments have a reduced risk of developing tumors. But how bariatric surgery directly impacts cancer progression has not been well studied: does it slow tumor growth or boost the anti-tumor immune response?

To answer these questions, Sipe et al. compared breast tumor growth in groups of laboratory mice that were obese due to being fed a high fat diet. The first group of mice lost weight after undergoing a bariatric surgery in which part of their stomach was removed. The second lost the same amount of weight but after receiving a restricted diet, and the third underwent a fake surgery and did not lose any weight. The experiments found that surgical weight loss cuts breast cancer tumor growth in half compared with obese mice. But mice who lost the same amount of weight through dietary restrictions had even less tumor growth than surgically treated mice.

The surgically treated mice who lost weight had more inflammation than mice in the two other groups, and had increased amounts of proteins and cells that block the immune response to tumors. Giving the surgically treated mice a drug that enhances the immune system’s ability to detect and destroy cancer cells reduced inflammation and helped shrink the mice’s tumors. Finally, Sipe et al. identified 54 genes which were turned on or off after bariatric surgery in both mice and humans, 11 of which were linked with tumor size.

These findings provide crucial new information about how bariatric surgery can impact cancer progression. Future studies could potentially use the conserved genes identified by Sipe et al. to develop new ways to stimulate the anti-cancer benefits of weight loss without surgery.

The obesity-breast cancer link: a multidisciplinary perspective

Obesity, exceptionally prevalent in the USA, promotes the incidence and progression of numerous cancer types including breast cancer. Complex, interacting metabolic and immune dysregulation marks the development of both breast cancer and obesity. Obesity promotes chronic low-grade inflammation, particularly in white adipose tissue, which drives immune dysfunction marked by increased pro-inflammatory cytokine production, alternative macrophage activation, and reduced T cell function. Breast tissue is predominantly composed of white adipose, and developing breast cancer readily and directly interacts with cells and signals from adipose remodeled by obesity. This review discusses the biological mechanisms through which obesity promotes breast cancer, the role of obesity in breast cancer health disparities, and dietary interventions to mitigate the adverse effects of obesity on breast cancer. We detail the intersection of obesity and breast cancer, with an emphasis on the shared and unique patterns of immune dysregulation in these disease processes. We have highlighted key areas of breast cancer biology exacerbated by obesity, including incidence, progression, and therapeutic response. We posit that interception of obesity-driven breast cancer will require interventions that limit protumor signaling from obese adipose tissue and that consider genetic, structural, and social determinants of the obesity–breast cancer link. Finally, we detail the evidence for various dietary interventions to offset obesity effects in clinical and preclinical studies of breast cancer. In light of the strong associations between obesity and breast cancer and the rising rates of obesity in many parts of the world, the development of effective, safe, well-tolerated, and equitable interventions to limit the burden of obesity on breast cancer are urgently needed.

Current State of Knowledge on the Immune Checkpoint Inhibitors in Triple-Negative Breast Cancer Treatment: Approaches, Efficacy, and Challenges

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype with limited treatment options. Recently, there has been a growing interest in immunotherapy with immune checkpoint inhibitors (ICIs) in TNBC, leading to extensive preclinical and clinical research. This review summarizes the current state of knowledge on ICIs efficacy and their predictive markers in TNBC and highlights the areas where the data are still limited. Currently, the only approved ICI-based regimen for TNBC is pembrolizumab with chemotherapy. Its advantage over chemotherapy alone was confirmed for non-metastatic TNBC regardless of programmed death-ligand 1 (PD-L1) expression (KEYNOTE-522) and for metastatic, PD-L1-positive TNBC (KEYNOTE-355). Pembrolizumab's efficacy was also evaluated in monotherapy, or in combination with niraparib and radiation therapy, showing potential efficacy and acceptable safety profile in phase 2 clinical trials. Atezolizumab + nab-paclitaxel increased the overall survival (OS) over placebo + nab-paclitaxel in early TNBC, regardless of PD-L1 status (IMpassion031). In IMpassion130 (untreated, advanced TNBC), the OS improvement was not statistically significant in the intention-to-treat population but clinically meaningful in the PD-L1 positive cohort. The durvalumab-anthracycline combination showed an increased response durability over placebo anthracycline in early TNBC (GeparNuevo). Several phase 1 clinical trials also showed a potential efficacy of atezolizumab and avelumab monotherapy in metastatic TNBC. ICIs appear to be applicable in both neoadjuvant and adjuvant settings, and are both pretreated and previously untreated patients. Further research is necessary to determine the most beneficial drug combinations and optimize patient selection. It is essential to identify the predictive markers for ICIs and factors affecting their expression.

The Role of the Adipokine Resistin in the Pathogenesis and Progression of Epithelial Ovarian Cancer

Obesity is a civilization disease associated with an increased risk of developing cardiovascular diseases, diabetes, and some malignancies. The results concerning the relationship between obesity and epithelial ovarian cancer (EOC) are inconclusive. The higher incidence of neoplasms in obese subjects has led to the development of the adipokine hypothesis. Omental adipocyte cells interact with cancer cells, promoting their migration and metastasis via the secretion of adipokines, growth factors, and hormones. One of the adipokines is resistin. It was shown in vitro that resistin stimulates the growth and differentiation of ovarian cancer cells. Moreover, it increases the level of angiogenesis factors, e.g., matrix metalloproteinase 2 (MMP-2) and vascular epithelial growth factor (VEGF). Additionally, resistin induces epithelial-mesenchymal transition (EMT) and stemness in EOC cell lines. A positive correlation has been shown between a higher level of resistin expression and the stage of histological differentiation of EOC or the occurrence of lymph node metastases. In addition, the overexpression of resistin has been found to act as an independent factor determining disease-free survival as well as overall survival in EOC patients. Growing evidence supports the finding that resistin plays an important role in some mechanisms leading to the progression of EOC, though this issue still requires further research.

Efficacy of immunotherapy in obese patients with cancer

Obesity is a condition of excessive fat tissue and high body mass index (BMI ≥30), which is increasing worldwide. Excess body weight is associated with poorer results in cancer treatments; however, recent studies emphasized that elevated BMI was associated with improved outcomes in cases treated by immune checkpoint inhibitor (ICI) therapies, which is called the obesity paradox. In this review, we discuss the correlation between obesity and cancer immunotherapy, especially ICIs, the underlying mechanisms, and the outcomes in different types of cancers. In addition, we describe the occurrence of immune-related adverse events (irAE) and the effect of gender in obese patients during immunotherapy using all relevant studies with available full texts.

Diet impacts triple-negative breast cancer growth, metastatic potential, chemotherapy responsiveness, and doxorubicin-mediated cardiac dysfunction

Anthracyclines are standard-of-care chemotherapy for the treatment of triple-negative breast cancer (TNBC). However, high anthracyclines cumulative doses increase heart failure risk. Designing therapeutic strategies that ameliorate cardiac toxicities without compromising oncologic efficacy are important to improve TNBC outcomes and survivorship. The purpose of this study was to determine the impact of diet on TNBC chemotherapeutic responsiveness and development of chemotherapy-induced cardiac damage. Female BALB/c mice fed a control, Western, Mediterranean, or Western + fish oil diet were injected with 1 × 106 4T1-luciferase TNBC into the mammary fat pad. Tumors grew for 21 days before surgical tumor resection, then mice were treated with 3.3 mg/kg i.v. doxorubicin for 3 weeks. Vevo (R) cardiac ultrasound was performed. Female nu/nu mice were placed on diets before 1 × 105  MDA-MB-231-luciferase TNBC were injected via the tail vein to induce the development of lung metastases. Mice were treated with saline or 3.3 mg/kg i.v. doxorubicin for 3 weeks, and the development of metastases visualized by IVIS (R). Consumption of a high-fat diet increased TNBC growth regardless of dietary pattern. Western diet-fed mice developed lung metastases sooner and displayed increased lung metastatic lesion formation, which was not observed in Mediterranean diet-fed mice. Western diet-fed animals displayed worse cardiac function when compared with Mediterranean diet-fed animals. Hearts from Western diet-fed animals displayed increased fibrosis. Diet represents a modifiable component directly impacting tumor growth, antitumor chemotherapy efficacy, and cardiac toxicities. Our data suggest that the Mediterranean diet may reduce lung metastatic lesions formation and prevent the development of cardiac toxicities.

Exploring the Impact of the Obesity Paradox on Lung Cancer and Other Malignancies

Simple Summary

Studies have shown that obesity is associated with many adverse health effects, including worse cancer outcomes. Many studies paradoxically suggest a survival benefit for obesity in treatment outcomes of cancers such as non-small-cell lung cancer. This relationship is not seen in animal models. We hypothesize that this relationship is secondary to suboptimal quantification of adiposity, enhanced immunotherapy response, and variables such as sex, medications, and smoking status. There are many ways to measure and classify adiposity, but the ability to distinguish abdominal obesity is likely key in predicting accurate prognosis. There are many ways obesity impacts cancer treatment course from diagnosis to survivorship. In this paper, we aim to analyze the factors contributing to the obesity paradox and its effect on lung cancer. This can aid the treatment and prognosis of lung cancer and may support further research into obesity-specific impacts on this malignancy.

Abstract

There is a paradoxical relationship between obesity, as measured by BMI, and many types of cancer, including non-small-cell lung cancer. Obese non-small-cell lung cancer patients have been shown to fare better than their non-obese counterparts. To analyze the multifaceted effects of obesity on oncologic outcomes, we reviewed the literature on the obesity paradox, methods to measure adiposity, the obesity-related derangements in immunology and metabolism, and the oncologic impact of confounding variables such as gender, smoking, and concomitant medications such as statins and metformin. We analyzed how these aspects may contribute to the obesity paradox and cancer outcomes with a focus on lung cancer. We concluded that the use of BMI to measure adiposity is limited and should be replaced by a method that can differentiate abdominal obesity. We also concluded that the concomitant metabolic and immunologic derangements caused by obesity contribute to the obesity paradox. Medications, gender, and smoking are additional variables that impact oncologic outcomes, and further research needs to be performed to solidify the mechanisms.

Racial disparities in health insurance, triple‑negative breast cancer diagnosis, tumor stage, treatment and survival in a large nationwide SEER cohort in the United States

It remains unclear whether there are racial disparities in mortality between women of different races who have the same subtype of breast cancer when tumor stage and size and treatment are controlled for. The present study aimed to investigate whether racial disparities in mortality existed between women of different races who had the same subtype of breast cancer when health insurance, tumor stage and size and treatment were controlled for in a large cohort of women with breast cancer in the United States. This study identified 399,564 women who were diagnosed with incident breast cancer at age ≥20 years between 2010 and 2016 in 17 Surveillance, Epidemiology and End Results (SEER) registries, including 277,319 non-Hispanic white (white), 44,149 non-Hispanic black (black), 34,141 non-Hispanic Asian or Pacific Islander (Asian) and 43,955 Hispanic women. White and Asian women exhibited a lower proportion of triple-negative breast cancer (9.8 and 9.1% respectively) than black (20.8%) and Hispanic women (12.6%). Black women had a significantly higher risk of all-cause mortality compared with white women in only those with triple-negative breast cancer (hazard ratio: 1.39, 95% CI: 1.29-1.51) and those with hormone receptor-negative/human epidermal growth factor receptor 2 (HER2)-positive breast cancer (1.53, 1.48-1.58) after adjusting for confounders. In those with hormone receptor-positive breast cancer, regardless of HER2 receptor status, the risk of all-cause mortality was not statistically different between black and white women, while the risk of breast cancer-specific mortality was significantly higher in all subtypes of breast cancer among black women. There were racial disparities in the presentation of triple-negative breast cancer and in all-cause and breast cancer specific mortality following stratification by triple-negative status and adjusting for tumor stage, size, grade and treatment.

The ambiguous role of obesity in oncology by promoting cancer but boosting antitumor immunotherapy

Obesity is nowadays considered a pandemic which prevalence's has been steadily increasingly in western countries. It is a dynamic, complex, and multifactorial disease which propitiates the development of several metabolic and cardiovascular diseases, as well as cancer. Excessive adipose tissue has been causally related to cancer progression and is a preventable risk factor for overall and cancer-specific survival, associated with poor prognosis in cancer patients. The onset of obesity features a state of chronic low-grade inflammation and secretion of a diversity of adipocyte-derived molecules (adipokines, cytokines, hormones), responsible for altering the metabolic, inflammatory, and immune landscape. The crosstalk between adipocytes and tumor cells fuels the tumor microenvironment with pro-inflammatory factors, promoting tissue injury, mutagenesis, invasion, and metastasis. Although classically established as a risk factor for cancer and treatment toxicity, recent evidence suggests mild obesity is related to better outcomes, with obese cancer patients showing better responses to treatment when compared to lean cancer patients. This phenomenon is termed obesity paradox and has been reported in different types and stages of cancer. The mechanisms underlying this paradoxical relationship between obesity and cancer are still not fully described but point to systemic alterations in metabolic fitness and modulation of the tumor microenvironment by obesity-associated molecules. Obesity impacts the response to cancer treatments, such as chemotherapy and immunotherapy, and has been reported as having a positive association with immune checkpoint therapy. In this review, we discuss obesity's association to inflammation and cancer, also highlighting potential physiological and biological mechanisms underlying this association, hoping to clarify the existence and impact of obesity paradox in cancer development and treatment.

Personalized Nutrition as a Key Contributor to Improving Radiation Response in Breast Cancer

Understanding metabolic and immune regulation inherent to patient populations is key to improving the radiation response for our patients. To date, radiation therapy regimens are prescribed based on tumor type and stage. Patient populations who are noted to have a poor response to radiation such as those of African American descent, those who have obesity or metabolic syndrome, or senior adult oncology patients, should be considered for concurrent therapies with radiation that will improve response. Here, we explore these populations of breast cancer patients, who frequently display radiation resistance and increased mortality rates, and identify the molecular underpinnings that are, in part, responsible for the radiation response and that result in an immune-suppressive tumor microenvironment. The resulting immune phenotype is discussed to understand how antitumor immunity could be improved. Correcting nutrient deficiencies observed in these populations should be considered as a means to improve the therapeutic index of radiation therapy.

Local Biomarkers Involved in the Interplay between Obesity and Breast Cancer

Simple Summary

Breast cancer is the second most common cancer in women worldwide. The risk of developing breast cancer depends on various mechanisms, such as age, heredity, reproductive factors, physical inactivity, and obesity. Obesity increases the risk of breast cancer and worsens outcomes for breast cancer patients. The rate of obesity is increasing worldwide, stressing the need for awareness of the association between obesity and breast cancer. In this review, we outline the biomarkers—including cellular and soluble factors—in the breast, associated with obesity, that affect the risk of breast cancer and breast cancer prognosis. Through these biomarkers, we aim to better identify patients with obesity with a higher risk of breast cancer and an inferior prognosis.

Abstract

Obesity is associated with an increased risk of breast cancer, which is the most common cancer in women worldwide (excluding non-melanoma skin cancer). Furthermore, breast cancer patients with obesity have an impaired prognosis. Adipose tissue is abundant in the breast. Therefore, breast cancer develops in an adipose-rich environment. During obesity, changes in the local environment in the breast occur which are associated with breast cancer. A shift towards a pro-inflammatory state is seen, resulting in altered levels of cytokines and immune cells. Levels of adipokines, such as leptin, adiponectin, and resistin, are changed. Aromatase activity rises, resulting in higher levels of potent estrogen in the breast. Lastly, remodeling of the extracellular matrix takes place. In this review, we address the current knowledge on the changes in the breast adipose tissue in obesity associated with breast cancer initiation and progression. We aim to identify obesity-associated biomarkers in the breast involved in the interplay between obesity and breast cancer. Hereby, we can improve identification of women with obesity with an increased risk of breast cancer and an impaired prognosis. Studies investigating mammary adipocytes and breast adipose tissue in women with obesity versus women without obesity are, however, sparse and further research is needed.

Baseline prognostic nutritional index and changes in pretreatment body mass index associate with immunotherapy response in patients with advanced cancer

Background

Recent research suggests that baseline body mass index (BMI) is associated with response to immunotherapy. In this study, we test the hypothesis that worsening nutritional status prior to the start of immunotherapy, rather than baseline BMI, negatively impacts immunotherapy response.

Methods

We studied 629 patients with advanced cancer who received immune checkpoint blockade at New York University. Patients had melanoma (n=268), lung cancer (n=128) or other primary malignancies (n=233). We tested the association between BMI changes prior to the start of treatment, baseline prognostic nutritional index (PNI), baseline BMI category and multiple clinical end points including best overall response (BOR), objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS) and overall survival (OS).

Results

Decreasing pretreatment BMI and low PNI were associated with worse BOR (p=0.04 and p=0.0004), ORR (p=0.01 and p=0.0005), DCR (p=0.01 and p<0.0001), PFS (p=0.02 and p=0.01) and OS (p<0.001 and p<0.001). Baseline BMI category was not significantly associated with any treatment outcomes.

Conclusion

Standard of care measures of worsening nutritional status more accurately associate with immunotherapy outcomes than static measurements of BMI. Future studies should focus on determining whether optimizing pretreatment nutritional status, a modifiable variable, leads to improvement in immunotherapy response.

Peptide Adjuvant to Invigorate Cytolytic Activity of NK Cells in an Obese Mouse Cancer Model

Cancer patients who are overweight compared to those with normal body weight have obesity-associated alterations of natural killer (NK) cells, characterized by poor cytotoxicity, slow proliferation, and inadequate anti-cancer activity. Concomitantly, prohibitin overexpressed by cancer cells elevates glucose metabolism, rendering the tumor microenvironment (TME) more tumor-favorable, and leading to malfunction of immune cells present in the TME. These changes cause vicious cycles of tumor growth. Adoptive immunotherapy has emerged as a promising option for cancer patients; however, obesity-related alterations in the TME allow the tumor to bypass immune surveillance and to down-regulate the activity of adoptively transferred NK cells. We hypothesized that inhibiting the prohibitin signaling pathway in an obese model would reduce glucose metabolism of cancer cells, thereby changing the TME to a pro-immune microenvironment and restoring the cytolytic activity of NK cells. Priming tumor cells with an inhibitory the prohibitin-binding peptide (PBP) enhances cytokine secretion and augments the cytolytic activity of adoptively transferred NK cells. NK cells harvested from the PBP-primed tumors exhibit multiple markers associated with the effector function of active NK cells. Our findings suggest that PBP has the potential as an adjuvant to enhance the cytolytic activity of adoptively transferred NK cells in cancer patients with obesity.

Current Landscape: The Mechanism and Therapeutic Impact of Obesity for Breast Cancer

Obesity is defined as a chronic disease induced by an imbalance of energy homeostasis. Obesity is a widespread health problem with increasing prevalence worldwide. Breast cancer (BC) has already been the most common cancer and one of the leading causes of cancer death in women worldwide. Nowadays, the impact of the rising prevalence of obesity has been recognized as a nonnegligible issue for BC development, outcome, and management. Adipokines, insulin and insulin-like growth factor, sex hormone and the chronic inflammation state play critical roles in the vicious crosstalk between obesity and BC. Furthermore, obesity can affect the efficacy and side effects of multiple therapies such as surgery, radiotherapy, chemotherapy, endocrine therapy, immunotherapy and weight management of BC. In this review, we focus on the current landscape of the mechanisms of obesity in fueling BC and the impact of obesity on diverse therapeutic interventions. An in-depth exploration of the underlying mechanisms linking obesity and BC will improve the efficiency of the existing treatments and even provide novel treatment strategies for BC treatment.

Exploiting the obesity-associated immune microenvironment for cancer therapeutics

Obesity causes chronic low-grade inflammation and leads to changes in the immune landscape of multiple organ systems. Given the link between chronic inflammatory conditions and cancer, it is not surprising that obesity is associated with increased risk and worse outcomes in many malignancies. Paradoxically, recent epidemiological studies have shown that high BMI is associated with increased efficacy of immune checkpoint inhibitors (ICI), and a causal relationship has been demonstrated in the preclinical setting. It has been proposed that obesity-associated immune dysregulation underlies this observation by inadvertently creating a favourable microenvironment for increased ICI efficacy. The recent success of ICIs in obese cancer patients raises the possibility that additional immune-targeted therapies may hold therapeutic value in this context. Here we review how obesity affects the immunological composition of the tumor microenvironment in ways that can be exploited for cancer immunotherapies. We discuss existing literature supporting a beneficial role for obesity during ICI therapy in cancer patients, potential opportunities for targeting the innate immune system to mitigate chronic inflammatory processes, and how to pinpoint obese patients who are most likely to benefit from immune interventions without relying solely on body mass index. Given that the incidence of obesity is expanding on an international scale, we propose that understanding obesity-associated inflammation is necessary to reduce cancer mortalities and capitalize on novel therapeutic opportunities in the era of cancer immunotherapy.

Immune checkpoint blockade reprograms systemic immune landscape and tumor microenvironment in obesity-associated breast cancer

Immune checkpoint blockade (ICB) has improved outcomes in some cancers. A major limitation of ICB is that most patients fail to respond, which is partly attributable to immunosuppression. Obesity appears to improve immune checkpoint therapies in some cancers, but impacts on breast cancer (BC) remain unknown. In lean and obese mice, tumor progression and immune reprogramming were quantified in BC tumors treated with anti-programmed death-1 (PD-1) or control. Obesity augments tumor incidence and progression. Anti-PD-1 induces regression in lean mice and potently abrogates progression in obese mice. BC primes systemic immunity to be highly responsive to obesity, leading to greater immunosuppression, which may explain greater anti-PD-1 efficacy. Anti-PD-1 significantly reinvigorates antitumor immunity despite persistent obesity. Laminin subunit beta-2 (Lamb2), downregulated by anti-PD-1, significantly predicts patient survival. Lastly, a microbial signature associated with anti-PD-1 efficacy is identified. Thus, anti-PD-1 is highly efficacious in obese mice by reinvigorating durable antitumor immunity. VIDEO ABSTRACT.

Pre-treatment high body mass index is associated with poor survival in Asian premenopausal women with localized breast cancer

Background: Obesity is associated with poor prognosis in breast cancer patients. This study aimed to evaluate the effect of obesity measured by body mass index (BMI) on survival of Taiwanese breast cancer patients in a single institution.

Methods: We observed 5000 patients who were diagnosed with stage I-III breast cancer between 1990 and 2005. Information on BMI at diagnosis, and clinical follow-up for disease recurrence and death, up to 20 years post-diagnosis were available. BMI (in kg/m²) categories included normal weight (BMI<24), overweight (24≤BMI<27), and obesity (BMI≥27), according to recommendations from the Bureau of Health Promotion of Taiwan. The role of BMI and other known prognostic factors for patient survival were evaluated in this patient cohort.

Results: Obesity was associated with advanced stage, higher nuclear grade, and higher percentages of estrogen receptor (ER) positive. The median age of patients with a higher BMI was greater than the median age of patients with a lower BMI. Obesity was an independent prognostic factor of overall survival (OS) (P<0.001), but not disease-free survival (DFS) (P=0.067). We subsequently analyzed the impact of age-stratified BMI (age<50 and age≥50 years) to ameliorate the impact of age bias. Following subset analyses, obesity correlated with shorter DFS (P=0.004) and OS (P=0.009) only in women<50 years of age. Multivariate analysis revealed that BMI was an independent prognostic factor for both DFS and OS in this group of patients. Subset analysis revealed that in women <50 years old, the impact of BMI on survival was associated with higher stage, ER negativity.

Conclusion: BMI is an independent prognostic factor of OS and DFS in breast cancer patients aged<50 years. Although the cause-effect relationship between obesity and survival is unclear, we recommend that weight control measures in young breast cancer survivors should be considered.

Impact of cholesterol-pathways on breast cancer development, a metabolic landscape

ApoB-lipoproteins and their components modulate intracellular metabolism and have been associated with the development of neoplastic phenomena, such as proliferation, anchorage-independent growth, epithelial-mesenchymal transition, and cancer invasion. In cancer cells, the modulation of targets that regulate cholesterol metabolism, such as synthesis de novo, endocytosis, and oxidation, are contributing factors to cancer development. While mechanisms associated with sterol regulatory element-binding protein 2 (SREBP-2)/mevalonate, the low-density lipoprotein receptor (LDL-R) and liver X receptor (LXR) have been linked with tumor growth; metabolites derived from cholesterol-oxidation, such as oxysterols and epoxy-cholesterols, also have been described as tumor processes-inducers. From this notion, we perform an analysis of the role of lipoproteins, their association with intracellular cholesterol metabolism, and the impact of these conditions on breast cancer development, mechanisms that can be shared during atherogenesis promoted mainly by LDL. Pathways connecting plasma dyslipidemias in conjunction with the effect of cholesterol-derived metabolites on intracellular mechanisms and cellular plasticity phenomena could provide new approaches to elucidate the triggering factors of carcinogenesis, conditions that could be considered in the development of new therapeutic approaches.

High-dimensional immunotyping of tumors grown in obese and non-obese mice

Obesity is a disease characterized by chronic low-grade systemic inflammation and has been causally linked to the development of 13 cancer types. Several studies have been undertaken to determine whether tumors evolving in obese environments adapt differential interactions with immune cells and whether this can be connected to disease outcome. Most of these studies have been limited to single-cell lines and tumor models and analysis of limited immune cell populations. Given the multicellular complexity of the immune system and its dysregulation in obesity, we applied high-dimensional suspension mass cytometry to investigate how obesity affects tumor immunity. We used a 36-marker immune-focused mass cytometry panel to interrogate the immune landscape of orthotopic syngeneic mouse models of pancreatic and breast cancer. Unanchored batch correction was implemented to enable simultaneous analysis of tumor cohorts to uncover the immunotypes of each cancer model and reveal remarkably model-specific immune regulation. In the E0771 breast cancer model, we demonstrate an important link to obesity with an increase in two T-cell-suppressive cell types and a decrease in CD8 T cells.

Metabolism of Innate Immune Cells in Cancer

Simple Summary

Both cancer cells and immune cells depend on specific metabolic programs for their survival and function. Depending on which metabolic changes occur, immune cells can either promote or suppress the antitumor immune response. This review summarizes the metabolic pathways that polarize innate immune cells for immune activation or suppression and describes the current clinical applications of these findings.

Abstract

Cancer cells possess specific metabolic requirements for their survival, proliferation, and progression. Within a shared microenvironment, immune cells depend on competing metabolic pathways for their development and effector function. As a result, local acidification, hypoxia, and nutrient depletion in the tumor microenvironment can alter the antitumor immune response and even promote resistance to immunotherapies such as immune checkpoint blockade and adoptive cell transfer. Although T cells are the primary effectors of the antitumor response, growing evidence demonstrates that innate immune cells are critical to successful tumor clearance. This review aims to summarize current research related to the innate immune system, metabolism, and cancer. We first discuss the specific metabolic requirements of innate immune cells for immune activation and suppression and conclude by highlighting ongoing clinical applications of these findings.

Impact of Body Mass Index on Survival Outcome in Patients with Newly Diagnosed Glioblastoma: A Retrospective Single-Center Study

Introduction:

The impact of obesity on survival outcomes in patients with glioblastoma (GBM) has not been well reported and the results for patients are currently unclear. We investigated the effect of obesity on survival outcomes in patients with newly diagnosed GBM.

Methods:

Using electronic medical records, all GBM patients that visited the Seoul St. Mary’s Hospital between 2008 and 2018 were reviewed. A total of 177 patients met our eligibility criteria. The cut-off point for BMI was 23.0 kg/m² based on previous studies which focused on Asian populations.

Results:

A total of 177 patients met our eligibility criteria. The overall median BMI of patients was 24.5 kg/m² (range 15.82-39.26). About 62 patients who had a BMI less than the cut-off value were assigned to the “lower BMI” group, while 115 patients who had a BMI greater than the cut-off value were assigned to the “higher BMI” group. In Kaplan-Meier survival analysis, the median OS of the higher BMI group was longer than that of the lower BMI group (21.3 months vs 15.3 months, P = .002). In multivariate Cox regression analysis for OS, lower BMI was associated with inferior OS (HR 1.48 CI 1.06-2.08, P = .002).

Conclusion:

Our findings suggest that elevated BMI may be associated with better survival in patients with newly diagnosed GBM. Additional larger prospective studies could help validate our findings to confirm the effect of body composition and survival outcomes in GBM patients.

A Risk Prediction Model for Breast Cancer Based on Immune Genes Related to Early Growth Response Proteins Family

Early growth response proteins (EGRs), a transcriptional regulatory family comprised of EGR1, EGR2, EGR3, and EGR 4, are reportedly involved in a vast array of functions. However, EGRs, as a whole, are rarely studied in breast cancer cases. This research was performed based on public datasets. The results demonstrated that, except EGR4, the other EGRs were differentially expressed genes in breast cancer. Subsequently, this study determined the prognosis significance of the EGR family, higher expression levels of EGRs indicating better overall survival (OS) and disease-free survival (DFS), except EGR4. So we attempted to explore the potential mechanism behind the prognostic value of EGRs. At the DNA level, however, neither DNA methylation status nor genetic alterations of EGRs contributed to the prognosis significance. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that EGRs were involved in several immune-related functions. Afterward, we assessed the correlation between EGRs and the immune system before establishing a risk prediction model with a 14-gene immune signature associated with EGRs, a prognostic nomogram predicting individuals’ 1-, 3-, and 5-year survival probabilities. The risk score was an independent prognosis predictor in the breast cancer cohorts. This study evidenced EGRs’ significance for tumor immunity, demonstrating that the EGR family may be a potential immunotherapeutic target for breast cancer. The 14-gene immune signature is a promising prognostic biomarker in breast cancer.

Polycyclic Aromatic Hydrocarbons and Mammary Cancer Risk: Does Obesity Matter too?

Breast cancer risk remains incompletely explained, and higher incidence rates of breast cancer over recent times and in urban and industrialized areas suggest environmental causes. Polycyclic aromatic hydrocarbons (PAH) are ubiquitous in the environment and epidemiological and rodent studies have shown associations between exposure to PAH and breast cancer incidence as well as mammary tumorigenesis. In addition, in vitro and rodent studies have implicated alterations in estrogen receptor alpha (Erα) signaling pathways following PAH exposure in limited experimental studies. However, our understanding of these mechanisms is incomplete. Sahay et al. addressed this gap by examining the effect of PAH exposure on epigenetic and transcriptional regulation of genes in the Erα pathway in a mouse cohort exposed to aerosolized PAH at proportions measured in urban air. In addition to alterations in the Erα signaling pathway in the pregnant mice and in their offspring and grandoffspring, the investigators observed higher body weights in mice exposed to PAH compared to the control. Given that associations between mammary tissue adiposity, systemic adiposity, and breast cancer risk have been observed previously, the finding of higher body weight in the PAH exposure group raises the possibility that body weight might influence the association between PAH exposure and breast cancer risk. Along with new analyses, we discuss the possibility that body weight may modify the association between PAH exposure, mammary cellular proliferation, and mammary gland ductal hyperplasia in offspring and grandoffspring mice and future research that may be needed to delineate these associations.