Obesity-associated inflammation promotes angiogenesis and breast cancer via angiopoietin-like 4

A novel pyroptosis-related lncRNA signature for prognostic prediction in patients with lung adenocarcinoma

Lung adenocarcinoma (LUAD) has been the major cause of tumor-associated mortality in recent years and has a poor prognosis. Pyroptosis is regulated via the activation of inflammasomes and participates in tumorigenesis. However, the effects of pyroptosis-related lncRNAs (PRlncRNAs) on LUAD have not yet been completely elucidated. Therefore, we attempted to systematically explore patterns of cell pyroptosis to establish a novel signature for predicting LUAD survival. Based on TCGA database, we set up a prognostic model by incorporating PRlncRNAs with differential expression using Cox regression and LASSO regression. Kaplan-Meier analysis was conducted to compare the survival of LUAD patients. We further simplified the risk model and created a nomogram to enhance the prediction of LUAD prognosis. Altogether, 84 PRlncRNAs with differential expression were discovered. Subsequently, a new risk model was constructed based on five PRlncRNAs, GSEC, FAM83A-AS1, AL606489.1, AL034397.3 and AC010980.2. The proposed signature exhibited good performance in prognostic prediction and was related to immunocyte infiltration. The nomogram exactly forecasted the overall survival of patients and had excellent clinical utility. In the present study, the five-lncRNA prognostic risk signature and nomogram are trustworthy and effective indicators for predicting the prognosis of LUAD.

Emerging roles of angiopoietin-like proteins in inflammation: Mechanisms and potential as pharmacological targets

Angiopoietin-like proteins (ANGPTLs), a family of eight secreted glycoproteins termed ANGTPL1-8, are involved in angiogenesis, lipid metabolism, cancer progression, and inflammation. Their roles in regulating lipid metabolism have been intensively studied, as some ANGPTLs are promising pharmacological targets for hypertriglyceridemia and associated cardiovascular disease. Recently, the emerging roles of ANGPTLs in inflammation have attracted great attention. First, elevated levels of multiple circulating ANGPTLs in inflammatory diseases make them potential disease biomarkers. Second, multiple ANGPTLs regulate acute or chronic inflammation via various mechanisms, including triggering inflammatory signaling through their action as ligands for integrin or forming homo- /hetero-oligomers to regulate signal transduction via extra- or intracellular mechanisms. As dysregulation of the inflammatory response is a critical trigger in many diseases, understanding the roles of ANGPTLs in inflammation will aid in drug/therapy development. Here, we summarize the roles, mechanisms, and potential therapeutic values for ANGPTLs in inflammation and inflammatory diseases.

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.

Immunotherapy in endometrial cancer: rationale, practice and perspectives

Tumor immunotherapy has attracted more and more attention nowadays, and multiple clinical trials have confirmed its effect in a variety of solid tumors. Immune checkpoint inhibitors (ICIs), cancer vaccines, adoptive cell transfer (ACT), and lymphocyte-promoting cytokines are the main immunotherapy methods. Endometrial cancer (EC) is one of the most frequent tumors in women and the prognosis of recurrent or metastatic EC is poor. Since molecular classification has been applied to EC, immunotherapy for different EC subtypes (especially POLE and MSI-H) has gradually attracted attention. In this review, we focus on the expression and molecular basis of the main biomarkers in the immunotherapy of EC firstly, as well as their clinical application significance and limitations. Blocking tumor immune checkpoints is one of the most effective strategies for cancer treatment in recent years, and has now become the focus in the field of tumor research and treatment. We summarized clinical date of planned and ongoing clinical trials and introduced other common immunotherapy methods in EC, such as cancer vaccine and ACT. Hormone aberrations, metabolic syndrome (MetS) and p53 mutant and that affect the immunotherapy of endometrial cancer will also be discussed in this review.

Obesity and aging: Molecular mechanisms and therapeutic approaches

The epidemic of obesity is a major challenge for health policymakers due to its far-reaching effects on population health and potentially overwhelming financial burden on healthcare systems. Obesity is associated with an increased risk of developing acute and chronic diseases, including hypertension, stroke, myocardial infarction, cardiovascular disease, diabetes, and cancer. Interestingly, the metabolic dysregulation associated with obesity is similar to that observed in normal aging, and substantial evidence suggests the potential of obesity to accelerate aging. Therefore, understanding the mechanism of fat tissue dysfunction in obesity could provide insights into the processes that contribute to the metabolic dysfunction associated with the aging process. Here, we review the molecular and cellular mechanisms underlying both obesity and aging, and how obesity and aging can predispose individuals to chronic health complications. The potential of lifestyle and pharmacological interventions to counter obesity and obesity-related pathologies, as well as aging, is also addressed.

PPARs and Tumor Microenvironment: The Emerging Roles of the Metabolic Master Regulators in Tumor Stromal-Epithelial Crosstalk and Carcinogenesis

Peroxisome proliferator-activated receptors (PPARs) have been extensively studied for more than three decades. Consisting of three isotypes, PPARα, γ, and β/δ, these nuclear receptors are regarded as the master metabolic regulators which govern many aspects of the body energy homeostasis and cell fate. Their roles in malignancy are also increasingly recognized. With the growing interest in crosstalk between tumor stroma and epithelium, this review aims to highlight the current knowledge on the implications of PPARs in the tumor microenvironment. PPARγ plays a crucial role in the metabolic reprogramming of cancer-associated fibroblasts and adipocytes, coercing the two stromal cells to become substrate donors for cancer growth. Fibroblast PPARβ/δ can modify the risk of tumor initiation and cancer susceptibility. In endothelial cells, PPARβ/δ and PPARα are pro- and anti-angiogenic, respectively. Although the angiogenic role of PPARγ remains ambiguous, it is a crucial regulator in autocrine and paracrine signaling of cancer-associated fibroblasts and tumor-associated macrophages/immune cells. Of note, angiopoietin-like 4 (ANGPTL4), a secretory protein encoded by a target gene of PPARs, triggers critical oncogenic processes such as inflammatory signaling, extracellular matrix derangement, anoikis resistance and metastasis, making it a potential drug target for cancer treatment. To conclude, PPARs in the tumor microenvironment exhibit oncogenic activities which are highly controversial and dependent on many factors such as stromal cell types, cancer types, and oncogenesis stages. Thus, the success of PPAR-based anticancer treatment potentially relies on innovative strategies to modulate PPAR activity in a cell type-specific manner.

Mechanistic Targets and Nutritionally Relevant Intervention Strategies to Break Obesity-Breast Cancer Links

The worldwide prevalence of overweight and obesity has tripled since 1975. In the United States, the percentage of adults who are obese exceeds 42.5%. Individuals with obesity often display multiple metabolic perturbations, such as insulin resistance and persistent inflammation, which can suppress the immune system. These alterations in homeostatic mechanisms underlie the clinical parameters of metabolic syndrome, an established risk factor for many cancers, including breast cancer. Within the growth-promoting, proinflammatory milieu of the obese state, crosstalk between adipocytes, immune cells and breast epithelial cells occurs via obesity-associated hormones, angiogenic factors, cytokines, and other mediators that can enhance breast cancer risk and/or progression. This review synthesizes evidence on the biological mechanisms underlying obesity-breast cancer links, with emphasis on emerging mechanism-based interventions in the context of nutrition, using modifiable elements of diet alone or paired with physical activity, to reduce the burden of obesity on breast cancer.

The Influence of Biologically Active Substances Secreted by the Adipose Tissue on Endometrial Cancer

Endometrial cancer is one of the most frequently diagnosed gynecological neoplasms in developed countries and its incidence is rising. Usually, it is diagnosed in the early stages of the disease and has a good prognosis; however, in later stages, the rate of recurrence reaches up to 60%. The discrepancy in relapse rates is due to the heterogeneity of the group related to the presence of prognostic factors affecting survival parameters. Increased body weight, diabetes, metabolic disturbances and estrogen imbalance are important factors for the pathogenesis of endometrial cancer. Even though prognostic factors such as histopathological grade, clinical stage, histological type and the presence of estrogen and progesterone receptors are well known in endometrial cancer, the search for novel prognostic biomarkers continues. Adipose tissue is an endocrine organ involved in metabolism, immune response and the production of biologically active substances participating in cell growth and differentiation, angiogenesis, apoptosis and carcinogenesis. In this manuscript, we review the impact of factors secreted by the adipose tissue involved in the regulation of glucose and lipid metabolism (leptin, adiponectin, omentin, vaspin, galectins) and factors responsible for homeostasis maintenance, inflammatory processes, angiogenesis and oxidative stress (IL-1β, 6, 8, TNFα, Vascular endothelial growth factor (VEGF), Fibroblast growth factors (FGFs)) in the diagnosis and prognosis of endometrial cancer.

Myeloid-Derived Suppressor Cells: Facilitators of Cancer and Obesity-Induced Cancer

Immature myeloid cells at varied stages of differentiation, known as myeloid-derived suppressor cells (MDSC), are present in virtually all cancer patients. MDSC are profoundly immune-suppressive cells that impair adaptive and innate antitumor immunity and promote tumor progression through nonimmune mechanisms. Their widespread presence combined with their multitude of protumor activities makes MDSC a major obstacle to cancer immunotherapies. MDSC are derived from progenitor cells in the bone marrow and traffic through the blood to infiltrate solid tumors. Their accumulation and suppressive potency are driven by multiple tumor- and host-secreted proinflammatory factors and adrenergic signals that act via diverse but sometimes overlapping transcriptional pathways. MDSC also accumulate in response to the chronic inflammation and lipid deposition characteristic of obesity and contribute to the more rapid progression of cancers in obese individuals. This article summarizes the key aspects of tumor-induced MDSC with a focus on recent progress in the MDSC field.

Pancreatic Tumorigenesis: Oncogenic KRAS and the Vulnerability of the Pancreas to Obesity

Simple Summary

Pancreatic cancer is a devastating disease with a poor survival rate, and oncogenic mutant KRAS is a major driver of its initiation and progression; however, effective strategies/drugs targeting major forms of mutant KRAS have not been forthcoming. Of note, obesity is known to worsen mutant KRAS-mediated pathologies, leading to PDAC with high penetrance; however, the mechanistic link between obesity and pancreatic cancer remains elusive. The recent discovery of FGF21 as an anti-obesity and anti-inflammation factor and as a downstream target of KRAS has shed new light on the problem.

Abstract

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies and KRAS (Kirsten rat sarcoma 2 viral oncogene homolog) mutations have been considered a critical driver of PDAC initiation and progression. However, the effects of mutant KRAS alone do not recapitulate the full spectrum of pancreatic pathologies associated with PDAC development in adults. Historically, mutant KRAS was regarded as constitutively active; however, recent studies have shown that endogenous levels of mutant KRAS are not constitutively fully active and its activity is still subject to up-regulation by upstream stimuli. Obesity is a metabolic disease that induces a chronic, low-grade inflammation called meta-inflammation and has long been recognized clinically as a major modifiable risk factor for pancreatic cancer. It has been shown in different animal models that obesogenic high-fat diet (HFD) and pancreatic inflammation promote the rapid development of mutant KRAS-mediated PDAC with high penetrance. However, it is not clear why the pancreas with endogenous levels of mutant KRAS is vulnerable to chronic HFD and inflammatory challenges. Recently, the discovery of fibroblast growth factor 21 (FGF21) as a novel anti-obesity and anti-inflammatory factor and as a downstream target of mutant KRAS has shed new light on this problem. This review is intended to provide an update on our knowledge of the vulnerability of the pancreas to KRAS-mediated invasive PDAC in the context of challenges engendered by obesity and associated inflammation.

Obesity, Type 2 Diabetes, and Cancer Risk

Obesity and type 2 diabetes have both been associated with increased cancer risk and are becoming increasingly prevalent. Metabolic abnormalities such as insulin resistance and dyslipidemia are associated with both obesity and type 2 diabetes and have been implicated in the obesity-cancer relationship. Multiple mechanisms have been proposed to link obesity and diabetes with cancer progression, including an increase in insulin/IGF-1 signaling, lipid and glucose uptake and metabolism, alterations in the profile of cytokines, chemokines, and adipokines, as well as changes in the adipose tissue directly adjacent to the cancer sites. This review aims to summarize and provide an update on the epidemiological and mechanistic evidence linking obesity and type 2 diabetes with cancer, focusing on the roles of insulin, lipids, and adipose tissue.

Cellular and Molecular Players in the Interplay between Adipose Tissue and Breast Cancer

The incidence and severity of obesity are rising in most of the world. In addition to metabolic disorders, obesity is associated with an increase in the incidence and severity of a variety of types of cancer, including breast cancer (BC). The bidirectional interaction between BC and adipose cells has been deeply investigated, although the molecular and cellular players involved in these mechanisms are far from being fully elucidated. Here, we review the current knowledge on these interactions and describe how preclinical research might be used to clarify the effects of obesity over BC progression and morbidity, with particular attention paid to promising therapeutic interventions.

ANGPTL4 Expression in Ovarian Granulosa Cells Is Associated With Polycystic Ovary Syndrome

OBJECTIVES

This study aims to characterize the expression of ANGPTL4 in ovarian granulosa cells (GCs) and its association with polycystic ovary syndrome (PCOS).

METHODS

This study included 104 PCOS patients and 112 women in control group undergoing in vitro fertilization-embryo transfer (IVF-ET) from the reproductive hospital affiliated with Shandong University from 2019 to 2021. By reverse transcription and real-time quantitative (RT-q) PCR, the mRNA expression of ANGPTL4 in GCs was assessed, and clinical information for these patients were then reviewed and analyzed.

RESULTS

The RT-qPCR results showed that ANGPTL4 expression in the control group was significantly lower than that in the PCOS group (p = 0.000) and had positive association with AMH (r = 0.211), HOMA-IR (r = 0.174), LDL/HDL (r = 0.176), ApoB/ApoAI (r = 0.155), and TC/HDL (r = 0.189). Additionally, the high expression of ANGPTL4 in the ovarian granulosa cells might be an independent predictor in PCOS (OR: 3.345; 95% CI: 1.951-5.734) with a close contact with incidence of PCOS (AUC: 0.704; 95% CI: 0.633-0.774, p < 0.001).

CONCLUSIONS

Our study revealed higher ANGPTL4 expression in ovarian GCs with PCOS. Its association with glucose and lipid metabolism showed that ANGPTL4 might play an important role in PCOS metabolism and pathogenesis.

Obesity and Cancer Metastasis: Molecular and Translational Perspectives

Obesity is a modern health problem that has reached pandemic proportions. It is an established risk factor for carcinogenesis, however, evidence for the contribution of adipose tissue to the metastatic behavior of tumors is also mounting. Over 90% of cancer mortality is attributed to metastasis and metastatic tumor cells must communicate with their microenvironment for survival. Many of the characteristics observed in obese adipose tissue strongly mirror the tumor microenvironment. Thus in the case of prostate, pancreatic and breast cancer and esophageal adenocarcinoma, which are all located in close anatomical proximity to an adipose tissue depot, the adjacent fat provides an ideal microenvironment to enhance tumor growth, progression and metastasis. Adipocytes provide adipokines, fatty acids and other soluble factors to tumor cells whilst immune cells infiltrate the tumor microenvironment. In addition, there are emerging studies on the role of the extracellular vesicles secreted from adipose tissue, and the extracellular matrix itself, as drivers of obesity-induced metastasis. In the present review, we discuss the major mechanisms responsible for the obesity-metastatic link. Furthermore, understanding these complex mechanisms will provide novel therapies to halt the tumor-adipose tissue crosstalk with the ultimate aim of inhibiting tumor progression and metastatic growth.

Alpinetin delays high-fat diet-aggravated lung carcinogenesis

Alpinetin (ALP) has been reported to act as an anticancer agent. This study was carried out to elucidate the effect of ALP on high-fat diet (HFD)-induced aggressive cancer progression. C57BL/6 mice were fed with a control diet (CD) or HFD and administered with ALP. Following 6 weeks of feeding, mice were inoculated subcutaneously with Lewis lung carcinoma cells (LLC) to develop transplanted lung tumour. ALP suppressed cell proliferation which drives HFD-induced lung cancer progression. ALP inhibited lipid accumulation in tumour and tumour cells cultured in vitro. qPCR and ELISA analysis of tumour tissues revealed ALP restrained macrophages accumulation, M2s polarization and chemokine secretion. Further, in macrophages cultured in tumour cells conditioned medium (CM), ALP was confirmed to decrease M2s markers expression and chemokine production under high fat. These results demonstrate that ALP suppresses HFD-promoted harmful changes in tumour microenvironments which are crucial in curbing pulmonary tumour aggravation.

LncRNA CCAL Promotes Angiogenesis Through Regulating the MiR-29b/ANGPTL4 Axis in Osteosarcoma

Purpose

The objective of this study was to detect the expression of the long noncoding RNA (lncRNA) colorectal cancer-associated lncRNA (CCAL) in osteosarcoma tissues and to investigate its role in angiogenesis and the potential molecular mechanisms associated with this effect in osteosarcoma.

Materials and Methods

CCAL expression in 40 osteosarcoma tissues and 40 noncancerous tissues was measured by qRT-PCR (quantitative real-time polymerase chain reaction). Tube formation assays were performed to explore the role of CCAL in angiogenesis in osteosarcoma. In addition, the regulatory interaction between CCAL, miR-29b, and ANGPTL4 was investigated via luciferase reporter assay and bioinformatics predictive analysis.

Results

Compared with noncancerous tissues, the expression of CCAL was markedly upregulated in osteosarcoma tissues. Higher CCAL expression levels were closely related to shorter overall survival in patients with osteosarcoma. Additionally, functional analysis indicated that CCAL could facilitate tumour angiogenesis in vitro and in vivo in osteosarcoma. Mechanistically, CCAL upregulated ANGPTL4 expression in osteosarcoma cells, and ANGPTL4 mediated angiogenic induction by CCAL in osteosarcoma. Moreover, CCAL directly targeted miR-29b in osteosarcoma. More importantly, we demonstrated that CCAL upregulated the expression of ANGPTL4 by sponging miR-29b, which promoted angiogenesis in osteosarcoma.

Conclusion

Our results show that CCAL promotes angiogenesis by regulating the miR-29b/ANGPTL4 axis in osteosarcoma.

Regulation of Obesity by Antiangiogenic Herbal Medicines

Obesity is the result of an energy imbalance caused by an increased ratio of caloric intake to energy expenditure. In conjunction with obesity, related metabolic disorders, such as dyslipidemia, atherosclerosis, and type 2 diabetes, have become global health problems. Obesity progression is thought to be associated with angiogenesis and extracellular matrix (ECM) remodeling. Angiogenesis occurs in growing adult adipose tissues, which are similar to neoplastic tissues. Adipose tissue is highly vascularized, and each adipocyte is nourished by an extensive capillary network. Adipocytes produce proangiogenic factors, such as vascular endothelial growth factor A and fibroblast growth factor 2, which promote neovascularization within the adipose tissue. Furthermore, matrix metalloproteinases (MMPs), including MMP-2 and MMP-9, play important roles in adipose tissue development and microvessel maturation by modifying the ECM. Thus, modulation of angiogenesis and MMP activity provides a promising therapeutic approach for controlling human obesity and its related disorders. Over the past decade, there has been a great increase in the use of alternative treatments, such as herbal remedies, for these diseases. This review will focus on the role of angiogenesis in adipose tissue growth and the regulation of obesity by antiangiogenic herbal medicines.

HIFs, angiogenesis, and metabolism: elusive enemies in breast cancer

Hypoxia-inducible factors (HIFs) and the HIF-dependent cancer hallmarks angiogenesis and metabolic rewiring are well-established drivers of breast cancer aggressiveness, therapy resistance, and poor prognosis. Targeting of HIF and its downstream targets in angiogenesis and metabolism has been unsuccessful so far in the breast cancer clinical setting, with major unresolved challenges residing in target selection, development of robust biomarkers for response prediction, and understanding and harnessing of escape mechanisms. This Review discusses the pathophysiological role of HIFs, angiogenesis, and metabolism in breast cancer and the challenges of targeting these features in patients with breast cancer. Rational therapeutic combinations, especially with immunotherapy and endocrine therapy, seem most promising in the clinical exploitation of the intricate interplay of HIFs, angiogenesis, and metabolism in breast cancer cells and the tumor microenvironment.

ANGPTL4 overexpression inhibits tumor cell adhesion and migration and predicts favorable prognosis of triple-negative breast cancer

Background

Triple-negative breast cancer (TNBC) patients have relatively poor clinical outcomes. A marker predicting the prognosis of patients with TNBC could help guide treatment. Extensive evidence demonstrates that angiopoietin-like 4 (ANGPTL4) is involved in the regulation of cancer growth, metastasis and angiogenesis. Therefore, its role in TNBC is of interest.

Methods: We tested the ANGPTL4 expression level in tumor tissues by immunohistochemistry (IHC) and detected its association with the clinical features of TNBC patients. Next, the effects and mechanisms of ANGPTL4 on TNBC cell migration and adhesion were investigated.

Results

We found that ANGPTL4 overexpression was associated with favorable outcomes in TNBC patients. ANGPTL4 upregulation inhibited cell adhesion, migration and invasion in vitro. Further analyses demonstrated that the possible mechanism might involve suppression of TNBC progression by interacting with extracellular matrix-related genes.

Conclusions

The present findings demonstrated that enhancement of ANGPTL4 expression might inversely correlate with TNBC progression. ANGPTL4 is a promising marker of TNBC and should be evaluated in further studies.

Trial registration

Retrospectively registered.

Investigating Glioblastoma Response to Hypoxia

Glioblastoma (GB) is the most common and deadly type of primary malignant brain tumor with an average patient survival of only 15–17 months. GBs typically have hypoxic regions associated with aggressiveness and chemoresistance. Using patient derived GB cells, we characterized how GB responds to hypoxia. We noted a hypoxia-dependent glycolytic switch characterized by the up-regulation of HK2, PFKFB3, PFKFB4, LDHA, PDK1, SLC2A1/GLUT-1, CA9/CAIX, and SLC16A3/MCT-4. Moreover, many proangiogenic genes and proteins, including VEGFA, VEGFC, VEGFD, PGF/PlGF, ADM, ANGPTL4, and SERPINE1/PAI-1 were up-regulated during hypoxia. We detected the hypoxic induction of invasion proteins, including the plasminogen receptor, S100A10, and the urokinase plasminogen activator receptor, uPAR. Furthermore, we observed a hypoxia-dependent up-regulation of the autophagy genes, BNIP-3 and DDIT4 and of the multi-functional protein, NDRG1 associated with GB chemoresistance; and down-regulation of EGR1 and TFRC (Graphical abstract). Analysis of GB patient cohorts’ revealed differential expression of these genes in patient samples (except SLC16A3) compared to non-neoplastic brain tissue. High expression of SLC2A1, LDHA, PDK1, PFKFB4, HK2, VEGFA, SERPINE1, TFRC, and ADM was associated with significantly lower overall survival. Together these data provide important information regarding GB response to hypoxia which could support the development of more effective treatments for GB patients.

Cancer-associated adipocytes: emerging supporters in breast cancer

Breast cancer (BC) is a malignant breast tumor confronted with high invasion, metastasis and recurrence rate, and adipocytes are the largest components in breast tissue. The aberrant adipocytes, especially the BC-neighbored cancer-associated adipocytes (CAAs), are found in the invasive front of BC. CAAs present a vicious phenotype compared with mature mammary adipocytes and mediate the crosstalk network between adipocytes and BC cells. By releasing multiple adipokines such as leptin, adiponectin, interleukin (IL)-6, chemokine ligand 2 (CCL2) and chemokine ligand 5 (CCL5), CAAs play essential roles in favor of proliferation, angiogenesis, dissemination, invasion and metastasis of BC. This article reviews the recent existing CAAs studies on the functions and mechanisms of adipocytes in the development of BC, including adipokine regulating, metabolic reprogramming, extracellular matrix (ECM) remodeling, microRNAs (miRNAs) and immune cell adjusting. Besides, adipocyte secretome and cellular interactions are implicated in the intervention to BC therapy and autologous fat grafting of breast reconstruction. Therefore, the potential functions and mechanisms of CAAs are very important for unveiling BC oncogenesis and progress. Deciphering the complex network between CAAs and BC is critical for designing therapeutic strategies and achieving the maximum therapeutic effects of BC.

The Molecular Adaptive Responses of Skeletal Muscle to High-Intensity Exercise/Training and Hypoxia

High-intensity exercise/training, especially interval exercise/training, has gained popularity in recent years. Hypoxic training was introduced to elite athletes half a century ago and has recently been adopted by the general public. In the current review, we have summarised the molecular adaptive responses of skeletal muscle to high-intensity exercise/training, focusing on mitochondrial biogenesis, angiogenesis, and muscle fibre composition. The literature suggests that (peroxisome proliferator-activated receptor gamma coactivator 1-alpha) PGC-1α, vascular endothelial growth factor (VEGF), and hypoxia-inducible factor 1-alpha (HIF1-α) might be the main mediators of skeletal muscle adaptations to high-intensity exercises in hypoxia. Exercise is known to be anti-inflammatory, while the effects of hypoxia on inflammatory signalling are more complex. The anti-inflammatory effects of a single session of exercise might result from the release of anti-inflammatory myokines and other cytokines, as well as the downregulation of Toll-like receptor signalling, while training-induced anti-inflammatory effects may be due to reductions in abdominal and visceral fat (which are main sources of pro-inflammatory cytokines). Hypoxia can lead to inflammation, and inflammation can result in tissue hypoxia. However, the hypoxic factor HIF1-α is essential for preventing excessive inflammation. Disease-induced hypoxia is related to an upregulation of inflammatory signalling, but the effects of exercise-induced hypoxia on inflammation are less conclusive. The effects of high-intensity exercise under hypoxia on skeletal muscle molecular adaptations and inflammatory signalling have not been fully explored and are worth investigating in future studies. Understanding these effects will lead to a more comprehensive scientific basis for maximising the benefits of high-intensity exercise.

Interleukin-1β and Cancer

Within a tumor, IL-1β is produced and secreted by various cell types, such as immune cells, fibroblasts, or cancer cells. The IL1B gene is induced after "priming" of the cells and a second signal is required to allow IL-1β maturation by inflammasome-activated caspase-1. IL-1β is then released and leads to transcription of target genes through its ligation with IL-1R1 on target cells. IL-1β expression and maturation are guided by gene polymorphisms and by the cellular context. In cancer, IL-1β has pleiotropic effects on immune cells, angiogenesis, cancer cell proliferation, migration, and metastasis. Moreover, anti-cancer treatments are able to promote IL-1β production by cancer or immune cells, with opposite effects on cancer progression. This raises the question of whether or not to use IL-1β inhibitors in cancer treatment.

Obesity and Breast Cancer: A Case of Inflamed Adipose Tissue

Obesity is associated with an increased risk of estrogen receptor-positive breast cancer in postmenopausal women and a worse prognosis for all major breast cancer subtypes regardless of menopausal status. While the link between obesity and the pathogenesis of breast cancer is clear, the molecular mechanism of this association is not completely understood due to the complexity of both obesity and breast cancer. The aim of this review is to highlight the association between obesity and breast cancer and discuss the literature, which indicates that this association is due to chronic adipose tissue inflammation. We will discuss the epidemiological data for the association between breast cancer incidence and progression as well as the potential molecular mechanisms for this association. We will focus on the role of inflammation within the adipose tissue during the pathogenesis of breast cancer. A better understanding of how obesity and adipose tissue inflammation affects the pathogenesis of breast cancer will lead to new strategies to reduce breast cancer risk and improve patient outcomes for obese patients.

Identification of Aurora Kinase A as a Biomarker for Prognosis in Obesity Patients with Early Breast Cancer

BACKGROUND

Obesity is associated both with a higher risk of developing breast cancer, particularly in postmenopausal women, and with worse disease outcome for women of all ages. Previous investigation suggested Aurora A kinase was able to partially restore the functionalities of obese adipose-derived mesenchymal stem cells by stabilizing their primary cilia and reestablishing a balance of multiple stemness-associated genes. The association between Aurora A and obesity breast cancer is still unclear. We hypothesized that overexpression of Aurora A was associated with poor survival in obesity breast cancer and the related axis mechanism was involved.

METHODS

A total of 517 primary breast cancer specimens were collected from the First Affiliated Hospital of China Medical University between January 2011 and November 2016. Our independent variable was BMI at baseline, categorized as overweight (BMI ≥25 kg/m2, as obesity cohort), and normal (18.5 ≤ BMI <25 kg/m2, as non-obesity cohort). The immunohistochemical (IHC) staining was performed with Aurora A, Survivin, MMP11, Cyclin B1, and Cathepsin L. Kaplan-Meier curve was used to analyze overall survival in our cohorts and TCGA-BRCA data (GSE3494). Log rank test was used to calculate P values. Protein-protein interaction (PPI) network analysis and MCODE model were used to analyze the Aurora-altered signal pathway from GSE78958.

RESULTS

Among 517 breast patients, Aurora A-positive (staining scores ≥4) was significantly higher in obesity breast carcinoma compared with non-obesity cancer carcinoma (χ 2=9.79, P=0.002), with more frequency in hormone receptor-negative (68.4% vs 77.9%, P=0.015) and HER2-positive patients (28.7% vs 17.9%, P=0.003). High Aurora A expression was remarkably and significantly associated with overall survival (OS) (8-year OS ratio: 69.5% vs 81.1%, OR=1.76, 95% CI: 1.03~3.02, P=0.041) in obesity cohort. Interestingly, higher expression of Aurora A was not associated with a shorter overall survival time among the non-obesity breast cancer (8-year OS ratio: 81.4% vs 85.8%, OR=1.40, 95% CI: 0.79~2.45, P=0.229). As for RFS, the expression levels of Aurora A expression genes have no significance with RFS statistically in non-obesity and obesity patients. Aurora A and lymph node metastases were significantly poor prognostic factors for OS, and borderline significance was noted for high BMI. Kaplan-Meier survival analysis from TCGA database confirmed that the high Aurora A expression group had worse prognosis (HR=1.47, 95% CI: 1.14-1.90, P=0.003). The KEGG pathway enrichment results were consistent with GO biological process term analysis, in which CCNB1 was enriched for upregulated Aurora A. In our samples, Aurora A level on tumor cytoplasm had broad connections with Cyclin B1 by IHC correlation analysis (correlation coefficient = 0.227, P=0.001).

CONCLUSION

Our finding demonstrates here for the first time that high expression of Aurora A was notably correlated with early recurrence and poor overall survival in obesity patients with early breast cancer. The Aurora A-Cyclin B1 axis could be a potential promising therapeutic target for cancer intervention and therapy.

Obesity Reduces Maternal Blood Triglyceride Concentrations by Reducing Angiopoietin-Like Protein 4 Expression in Mice

To ensure fetal lipid supply, maternal blood triglyceride (TG) concentrations are robustly elevated during pregnancy. Interestingly, a lower increase in maternal blood TG concentrations has been observed in some obese mothers. We have shown that high-fat (HF) feeding during pregnancy significantly reduces maternal blood TG levels. Therefore, we performed this study to investigate if and how obesity alters maternal blood TG levels. Maternal obesity was established by prepregnant HF (ppHF) feeding, which avoided the dietary effect during pregnancy. We found not only that maternal blood TG concentrations in ppHF dams were remarkably lower than in control dams but also that the TG peak occurred earlier during gestation. Hepatic TG production and intestinal TG absorption were unchanged in ppHF dams, but systemic lipoprotein lipase (LPL) activity was increased, suggesting that increased blood TG clearance contributes to the decreased blood TG concentrations in ppHF dams. Although significantly higher levels of UCP1 protein were observed in interscapular brown adipose tissue (iBAT) of ppHF dams, Ucp1 gene deletion did not restore blood TG concentrations in ppHF dams. Expression of the angiopoietin-like protein 4 (ANGPTL4), a potent endogenous LPL inhibitor, was significantly increased during pregnancy. However, the pregnancy-induced elevation of blood TG was almost abolished in Angptl4 ^-/- dams. Compared with control dams, Angptl4 mRNA levels were significantly lower in iBAT, gonadal white adipose tissue, and livers of ppHF dams. Importantly, ectopic overexpression of ANGPTL4 restored maternal blood TG concentrations in ppHF dams. Together, these results indicate that ANGPTL4 plays a vital role in increasing maternal blood TG concentrations during pregnancy. Obesity impairs the rise of maternal blood TG concentrations by reducing ANGPTL4 expression in mice.

Weighing the Risk: effects of Obesity on the Mammary Gland and Breast Cancer Risk

Obesity is a preventable risk factor for breast cancer following menopause. Regardless of menopausal status, obese women who develop breast cancer have a worsened prognosis. Breast tissue is comprised of mammary epithelial cells organized into ducts and lobules and surrounded by adipose-rich connective tissue. Studies utilizing multiple in vivo models of obesity as well as human breast tissue have contributed to our understanding of how obesity alters mammary tissue. Localized changes in mammary epithelial cell populations, elevated secretion of adipokines and angiogenic mediators, inflammation within mammary adipose tissue, and remodeling of the extracellular matrix may result in an environment conducive to breast cancer growth. Despite these significant alterations caused by obesity within breast tissue, studies have suggested that some, but not all, obesity-induced changes may be mitigated with weight loss. Here, we review our current understanding regarding the impact of obesity on the breast microenvironment, how obesity-induced changes may contribute to breast tumor progression, and the impact of weight loss on the breast microenvironment.

Prognostic Inflammasome-Related Signature Construction in Kidney Renal Clear Cell Carcinoma Based on a Pan-Cancer Landscape

OBJECTIVE

To investigate the expression patterns and prognostic characteristics of inflammasome-related genes (IRGs) across cancer types and develop a robust biomarker for the prognosis of KIRC.

METHODS

The differentially expressed IRGs and prognostic genes among 10 cancers were analyzed based on The Cancer Genome Atlas (TCGA) dataset. Subsequently, an IRGs risk signature was developed in KIRC. Its prognostic accuracy was evaluated by receiver operating characteristic (ROC) analysis. The independent predictive capacity was identified by stratification survival and multivariate Cox analyses. The gene ontology (GO) analysis and principal component analysis (PCA) were performed to explore biological functions of the IRGs signature in KIRC.

RESULTS

The expression patterns and prognostic association of IRGs varied from different cancers, while KIRC showed the most abundant survival-related dysregulated IRGs. The IRG signature for KIRC was able to independently predict survival, and the signature genes were mainly involved inimmune-related processes.

CONCLUSIONS

The pan-cancer analysis provided a comprehensive landscape of IRGs across cancer types and identified a strong association between IRGs and the prognosis of KIRC. Further IRGs signature represented a reliable prognostic predictor for KIRC and verified the prognostic value of inflammasomes in KIRC, contributing to our understanding of therapies targeting inflammasomes for human cancers.

Mechanistic insights of adipocyte metabolism in regulating breast cancer progression

Adipocyte account for the largest component in breast tissue. Dysfunctional adipocyte metabolism, such as metaflammation in metabolically abnormal obese patients, will cause hyperplasia and hypertrophy of its constituent adipocytes. Inflamed adipose tissue is one of the biggest risk factors causing breast cancer. Factors linking adipocyte metabolism to breast cancer include dysfunctional secretion of proinflammatory mediators, proangiogenic factors and estrogens. The accumulation of tumor supporting cells and systemic effects, such as insulin resistance, dyslipidemia and oxidative stress, which are caused by abnormal adipocyte metabolism, further contribute to a more aggressive tumor microenvironment and stimulate breast cancer stem cell to influence the development and progression of breast cancer. Here, in this review, we focus on the adipocyte metabolism in regulating breast cancer progression, and discuss the potential targets which can be used for breast cancer therapy.

Obesity Promotes Cooperation of Cancer Stem-Like Cells and Macrophages to Enhance Mammary Tumor Angiogenesis

Obesity is correlated with worsened prognosis and treatment resistance in breast cancer. Macrophage-targeted therapies are currently in clinical trials, however, little is known about how obesity may impact treatment efficacy. Within breast adipose tissue, obesity leads to chronic, macrophage-driven inflammation, suggesting that obese breast cancer patients may benefit from these therapies. Using a high fat diet model of obesity, we orthotopically transplanted cancer cell lines into the mammary glands of obese and lean mice. We quantified changes in tumor invasiveness, angiogenesis and metastasis, and examined the efficacy of macrophage depletion to diminish tumor progression in obese and lean mice. Mammary tumors from obese mice grew significantly faster, were enriched for cancer stem-like cells (CSCs) and were more locally invasive and metastatic. Tumor cells isolated from obese mice demonstrated enhanced expression of stem cell-related pathways including Sox2 and Notch2. Despite more rapid growth, mammary tumors from obese mice had reduced necrosis, higher blood vessel density, and greater macrophage recruitment. Depletion of macrophages in obese tumor-bearing mice resulted in increased tumor necrosis, reduced endothelial cells, and enhanced recruitment of CD8⁺ T cells compared to IgG-treated controls. Macrophages may be an important clinical target to improve treatment options for obese breast cancer patients.

IL-1 Signaling in Tumor Microenvironment

Interleukin 1 (IL-1) has long been known for its pleiotropic effects on inflammation that plays a complex, and sometimes contrasting, role in different stages of cancer development. As a major proinflammatory cytokine, IL-1β is mainly expressed by innate immune cells. IL-1α, however, is expressed by various cell types under physiological and pathological conditions. IL-1R1 is the main receptor for both ligands and is expressed by various cell types, including innate and adaptive immune cell types, epithelial cells, endothelial cells, adipocytes, chondrocytes, fibroblasts, etc. IL-1 and IL-1R1 receptor interaction leads to a set of common signaling pathways, mainly the NF-kB and MAP kinase pathways, as a result of complex positive and negative regulations. The variety of cell types with IL-1R1 expression dictates the role of IL-1 signaling at different stages of cancer, which under certain circumstances leads to contrasting roles in tumor development. Recent availability of IL-1R1 conditional knockout mouse model has made it possible to dissect the role of IL-1/IL-1R1 signaling transduction in different cell types within the tumor microenvironment. This chapter will focus on the role of IL-1/IL-1R1 in different cell types within the tumor microenvironment and discuss the potential of targeting this pathway in cancer therapy.

Interaction of tumor cells and astrocytes promotes breast cancer brain metastases through TGF-β2/ANGPTL4 axes

Metastatic outcomes depend on the interactions of metastatic cells with a specific organ microenvironment. Our previous studies have shown that triple-negative breast cancer (TNBC) MDA-MB-231 cells passaged in astrocyte-conditioned medium (ACM) show proclivity to form brain metastases, but the underlying mechanism is unknown. The combination of microarray analysis, qPCR, and ELISA assay were carried out to demonstrate the ACM-induced expression of angiopoietin-like 4 (ANGPTL4) in TNBC cells. A stable ANGPTL4-knockdown MDA-MB-231 cell line was generated by ANGPTL4 short-hairpin RNA (shRNA) and inoculated into mice via left ventricular injection to evaluate the role of ANGPTL4 in brain metastasis formation. The approaches of siRNA, neutralizing antibodies, inhibitors, and immunoprecipitation were used to demonstrate the involved signaling molecules. We first found that ACM-conditioned TNBC cells upregulated the expression of ANGPTL4, a secreted glycoprotein whose effect on tumor progression is known to be tumor microenvironment- and tumor-type dependent. Knockdown of ANGPTL4 in TNBC MDA-MB-231 cells with shRNA decreased ACM-induced tumor cell metastatic growth in the brain and attributed to survival in a mouse model. Furthermore, we identified that astrocytes produced transforming growth factor-beta 2 (TGF-β2), which in part is responsible for upregulation of ANGPTL4 expression in TNBC through induction of SMAD signaling. Moreover, we identified that tumor cells communicate with astrocytes, where tumor cell-derived interleukin-1 beta (IL-1β) and tumor necrosis factor alpha (TNF-α) increased the expression of TGF-β2 in astrocytes. Collectively, these findings indicate that the invading TNBC cells interact with astrocytes in the brain microenvironment that facilitates brain metastases of TNBC cells through a TGF-β2/ANGPTL4 axis. This provides groundwork to target ANGPTL4 as a treatment for breast cancer brain metastases.

Insights into inflammasome and its research advances in cancer

Inflammation has long been proven to engage in tumor initiation and progression. Inflammasome, as a member of innate immunity-induced host defense inflammation, also plays critical roles in cancer. Inflammasome is a multiprotein complex responding to pathogen-associated molecular patterns and damage-associated molecular patterns. It is composed of receptors such as NOD-like receptors and AIM2-like receptors, adaptor protein ASC, and effector caspase-1, which can process proinflammatory cytokines interleukin (IL)-1β and IL-18. It has been reported that upregulated inflammasome activity is correlated to various types of cancers including breast cancer, gastric cancer, brain tumor, and malignant prostate, while inflammasomes also have a protective role in colitis-associated cancer. Autophagy, an intracellular recycling process for maintaining homeostasis, is deemed to contribute to the underlying mechanism of its dual roles in cancer. It has been found that distinct tumor stages and different isotypes of caspases involved in the inflammasome pathway can affect the roles of inflammasome in cancer. In this review, we update the latest evidence of inflammasome roles in cancer and novel inflammasome pathway-targeting agents for immunotherapy and discuss future research directions of inflammasome-based target therapy.

The Role of Metabolic Syndrome in Endometrial Cancer: A Review

Endometrial cancer is one of the most common cancers of the female reproductive system. Although surgery, radiotherapy, chemotherapy, and hormone therapy can significantly improve the survival of patients, the treatment of patients with very early lesions and a strong desire to retain reproductive function or late recurrence is still in the early stages. Metabolic syndrome (MS) is a clustering of at least three of the five following medical conditions: central obesity, high blood pressure, high blood sugar, high serum triglycerides, and low serum high-density lipoprotein (HDL). Obesity, diabetes and hypertension often coexist in patients with endometrial cancer, which increases the risk of endometrial cancer, also known as the "triple syndrome of endometrial cancer." In recent years, epidemiological and clinical studies have found that MS associated with metabolic diseases is closely related to the incidence of endometrial cancer. However, the key molecular mechanisms underlying the induction of endometrial cancer by MS have not been elucidated to date. Characterizing the tumor metabolism microenvironment will be advantageous for achieving a comprehensive view of the molecular mechanism of metabolic syndrome associated with endometrial cancer and for providing a new target for the treatment of endometrial cancer. This review focuses on recent advances in determining the role of metabolic syndrome-related factors and mechanisms in the pathogenesis of endometrial cancer. We suggest that interfering with the tumor metabolic microenvironment-related molecular signals may inhibit the occurrence of endometrial cancer.

Recruitment of stromal cells into tumour microenvironment promote the metastatic spread of breast cancer

Currently, metastasis remains the primary cause of death of patients with breast cancer despite the important advances in the treatment of this disease. In the complex tumour microenvironment network, several malignant and non-malignant cell types as well as components of extracellular matrix cooperate in promoting the metastatic spread of breast carcinoma. Many components of the stromal compartment are recruited from distant sites to the tumour including mesenchymal stem cells, endothelial cells, macrophages and other immune cells whereas other cells such as fibroblasts are already present in both primary and secondary lesions. When these cells come into contact with cancer cells they are "educated" and acquire a pro-tumoural phenotype, which support all the steps of the metastatic cascade. In this Review, we highlight the role played by each stromal component in guiding cancer cells in their venture towards colonizing metastatic sites.

Hypoxia as a signal for prison breakout in cancer

PURPOSE OF REVIEW

We discuss recent discoveries in hypoxic cellular pathophysiology and explore the interplay between hypoxic malignant cells and other stromal elements. This review will provide an update on the effects of hypoxia on cancer outcomes and therapeutic resistance.

RECENT FINDINGS

Hypoxia has been discovered to be a key driver for tumor progression, both because of impacts on tumor cells and separately on the wider tumor microenvironment. The latter effects occur via epithelial mesenchymal transition, autophagy and metabolic switching. Through epithelial mesenchymal transition, hypoxia both drives metastasis and renders key target tissues receptive to metastasis. Autophagy is a double-edged sword which requires greater understanding to ascertain when it is a threat. Metabolic switching allows tumor cells to access hypoxic survival mechanisms even under normoxic conditions.Every element of the malignant stroma contributes to hypoxia-driven progression. Exosomal transfer of molecules from hypoxic tumor cells to target stromal cell types and the importance of microRNAs in intercellular communication have emerged as key themes.Antiangiogenic resistance can be caused by hypoxia-driven vasculogenic mimicry. Beyond this, hypoxia contributes to resistance to virtually all oncological treatment modalities.

SUMMARY

Recent advances have moved us closer to being able to exploit hypoxic mechanisms to overcome hypoxia-driven progression and therapy failure.

The Roles of ANGPTL Families in Cancer Progression

Angiopoietins play important roles in angiogenesis and the maintenance of hematopoietic stem cells. Angiopoietin-like proteins (ANGPTLs) are identified as proteins structurally similar to angiopoietins, and the ANGPTL family now consists of eight members. ANGPTLs are secretary proteins, and some ANGPTLs are not only angiogenic factors but also proteins with multiple functions such as glucose metabolism, lipid metabolism, redox regulation and chronic inflammation. Chronic inflammation is one of the key factors in carcinogenesis and cancer growth, proliferation, invasion and metastasis. ANGPTL 2, 3, 4, 6 and 7 are pro-inflammatory factors and regulate cancer progression, while ANGPTL1 inhibits tumor angiogenesis and metastasis. In this review, we describe the roles of ANGPTLs in cancer progression and discuss the possibility of disturbing the progression of cancer by regulating ANGPTLs expression.