The in vitro effect of the diabetes-associated markers insulin, leptin and oxidative stress on cellular characteristics promoting breast cancer progression is GLUT1-dependent

Bridging diabetes and cancer: harnessing biomarkers as dual sentinels for diagnosis, prognosis, and therapeutic advancements

The complex two-way relationship between diabetes mellitus (DM) and cancer poses a significant global health challenge. Shared mechanisms such as hyperinsulinemia, chronic inflammation, and oxidative stress create an environment that fosters cancer development, increasing the risk for certain cancers in individuals with diabetes, including pancreatic, colorectal, breast, liver, and endometrial malignancies. In this context, biomarkers emerge as essential tools, offering a means to untangle the connections between these two conditions by providing insights into early detection, diagnosis, prognosis, and treatment monitoring. For diabetic patients, biomarkers are particularly valuable as they help differentiate between changes caused by cancer and those driven by metabolic imbalances, illuminating disease evolution. This review examines the unique challenges encountered by diabetic patients with cancer, emphasizing the contributions of targeted biomarkers in identifying cancer subtypes, predicting outcomes, and guiding treatment decisions. We explore organ-specific biomarker profiles across various cancers, including pancreatic, colorectal, breast, liver, and lung, highlighting their potential to enhance diagnostic precision and enable personalized treatment strategies. Ultimately, we aim to illustrate how a deeper understanding of biomarker signatures can inform innovative clinical approaches and improve care for patients facing the dual burden of diabetes and cancer.

Pralatrexate represses the resistance of HCC cells to molecular targeted agents via the miRNA-34a/Notch pathway

Metabolism-related pathways are important targets for intervention in the treatment of hepatocellular carcinoma (HCC), but few studies have reported on the combination of inhibitors of folate metabolism-related enzymes and molecularly targeted drugs for HCC. The results of the present work are the first to reveal the effects of an inhibitor of dihydrofolate reductase (DHFR), pralatrexate, on the sensitivity of HCC cells to molecularly targeted agents examined using multiple assays. In HCC cells, knockdown of DHFR or treatment with pralatrexate enhanced the sensitivity of HCC cells to molecularly targeted agents, such as sorafenib, regorafenib, lenvatinib, cabozantinib, or anlotinib. Mechanically, pralatrexate decreased the methylation rates of miRNA-34a's promoter region to enhance the expression of miRNA-34a. Treatment with pralatrexate inhibited the expression of Notch and its downstream factors by enhancing the expression of miRNA-34a in HCC cells. In clinical specimens, the expression of miRNA-34a was negatively correlated with DHFR expression, while DHFR expression was positively correlated with the Notch intracellular domain (NICD) and downstream factors of the Notch pathway. The expression of miRNA-34a was negatively correlated with DHFR expression, while the methylation rates of miRNA-34a's promoter were positively related to DHFR. The effect of pralatrexate on the metabolic profile of HCC cells is very different from that of small molecule inhibitors related to glycolipid metabolism. Therefore, pralatrexate upregulates the sensitivity of HCC cells to molecularly targeted drugs. These results expand our understanding of folate metabolism and HCC and can help provide more options for HCC treatment.

Influence of Type 2 Diabetes and Adipose Tissue Dysfunction on Breast Cancer and Potential Benefits from Nutraceuticals Inducible in Microalgae

Breast cancer (BC) represents the most prevalent cancer in women at any age after puberty. From a pathogenetic prospective, despite a wide array of risk factors being identified thus far, poor metabolic health is emerging as a putative risk factor for BC. In particular, type 2 diabetes mellitus (T2DM) provides a perfect example bridging the gap between poor metabolic health and BC risk. Indeed, T2DM is preceded by a status of hyperinsulinemia and is characterised by hyperglycaemia, with both factors representing potential contributors to BC onset and progression. Additionally, the aberrant secretome of the dysfunctional, hypertrophic adipocytes, typical of obesity, characterised by pro-inflammatory mediators, is a shared pathogenetic factor between T2DM and BC. In this review, we provide an overview on the effects of hyperglycaemia and hyperinsulinemia, hallmarks of type 2 diabetes mellitus, on breast cancer risk, progression, treatment and prognosis. Furthermore, we dissect the role of the adipose-tissue-secreted adipokines as additional players in the pathogenesis of BC. Finally, we focus on microalgae as a novel superfood and a source of nutraceuticals able to mitigate BC risk by improving metabolic health and targeting cellular pathways, which are disrupted in the context of T2DM and obesity.

Oxidative Stress in Breast Cancer: A Biochemical Map of Reactive Oxygen Species Production

This review systematizes information about the metabolic features of breast cancer directly related to oxidative stress. It has been shown those redox changes occur at all levels and affect many regulatory systems in the human body. The features of the biochemical processes occurring in breast cancer are described, ranging from nonspecific, at first glance, and strictly biochemical to hormone-induced reactions, genetic and epigenetic regulation, which allows for a broader and deeper understanding of the principles of oncogenesis, as well as maintaining the viability of cancer cells in the mammary gland. Specific pathways of the activation of oxidative stress have been studied as a response to the overproduction of stress hormones and estrogens, and specific ways to reduce its negative impact have been described. The diversity of participants that trigger redox reactions from different sides is considered more fully: glycolytic activity in breast cancer, and the nature of consumption of amino acids and metals. The role of metals in oxidative stress is discussed in detail. They can act as both co-factors and direct participants in oxidative stress, since they are either a trigger mechanism for lipid peroxidation or capable of activating signaling pathways that affect tumorigenesis. Special attention has been paid to the genetic and epigenetic regulation of breast tumors. A complex cascade of mechanisms of epigenetic regulation is explained, which made it possible to reconsider the existing opinion about the triggers and pathways for launching the oncological process, the survival of cancer cells and their ability to localize.

Supplementation with a high-glucose drink stimulates anti-tumor immune responses to glioblastoma via gut microbiota modulation

A high-sugar diet induces lifestyle-associated metabolic diseases, such as obesity and diabetes, which may underlie the pro-tumor effects of a high-sugar diet. We supply GL261 syngeneic glioblastoma (GBM) mice with a short-term high-glucose drink (HGD) and find an increased survival rate with no evidence of metabolic disease. Modulation of the gut microbiota through HGD supplementation is critical for enhancing the anti-tumor immune response. Single-cell RNA sequencing shows that gut microbiota modulation by HGD supplementation increases the T cell-mediated anti-tumor immune response in GBM mice. We find that the cytotoxic CD4+ T cell population in GBM is increased due to synergy with anti-programmed cell death protein 1 (anti-PD-1) immune checkpoint inhibitors, but this effect depends upon HGD supplementation. Thus, we determine that HGD supplementation enhances anti-tumor immune responses in GBM mice through gut microbiota modulation and suggest that the role of HGD supplementation in GBM should be re-examined.

Molecular Mechanisms of Western Diet-Induced Obesity and Obesity-Related Carcinogenesis-A Narrative Review

The present study aims to provide a narrative review of the molecular mechanisms of Western diet-induced obesity and obesity-related carcinogenesis. A literature search of the Cochrane Library, Embase and Pubmed databases, Google Scholar and the grey literature was conducted. Most of the molecular mechanisms that induce obesity are also involved in the twelve Hallmarks of Cancer, with the fundamental process being the consumption of a highly processed, energy-dense diet and the deposition of fat in white adipose tissue and the liver. The generation of crown-like structures, with macrophages surrounding senescent or necrotic adipocytes or hepatocytes, leads to a perpetual state of chronic inflammation, oxidative stress, hyperinsulinaemia, aromatase activity, activation of oncogenic pathways and loss of normal homeostasis. Metabolic reprogramming, epithelial mesenchymal transition, HIF-1α signalling, angiogenesis and loss of normal host immune-surveillance are particularly important. Obesity-associated carcinogenesis is closely related to metabolic syndrome, hypoxia, visceral adipose tissue dysfunction, oestrogen synthesis and detrimental cytokine, adipokine and exosomal miRNA release. This is particularly important in the pathogenesis of oestrogen-sensitive cancers, including breast, endometrial, ovarian and thyroid cancer, but also 'non-hormonal' obesity-associated cancers such as cardio-oesophageal, colorectal, renal, pancreatic, gallbladder and hepatocellular adenocarcinoma. Effective weight loss interventions may improve the future incidence of overall and obesity-associated cancer.

BPA exposure enhances the metastatic aggression of ovarian cancer through the ERα/AKT/mTOR/HIF-1α signaling axis

Long-term exposure to bisphenol A (BPA) in humans may promote ovarian cancer development. In present study, the mechanisms by which BPA mediates the aggression metastatic behavior of ovarian cancer were investigated in vitro/in vivo. The results showed that BPA (10 μM) significantly promoted the proliferation, migration and invasion of human ovarian cancer cells (ES-2 and OVCAR-3 cells); moreover, it promoted ES-2 and OVCAR-3 cell glucose uptake, lactic acid release and intracellular ATP synthesis. After administration of 5 μg/kg/day BPA, tumor volume was increased compared with that in control group. KEGG and GO enrichment analyses showed that the genes from ES-2 cell in 10 μM BPA-treated group were enriched mainly in central carbon metabolism and PI3K-AKT signaling pathway. Then, qRT‒PCR and western blotting results showed that BPA (10 μM) increased the mRNA and protein expression levels of glycolysis-related genes and mTOR, p-AKT HIF-1α and ERα in vitro/vivo; whereas this effect was reduced after treatment with the ERα inhibitor methyl-piperidino-pyrazole. Furthermore, coimmunoprecipitation and mass spectrometry showed that BPA promoted the direct interaction of ERα with lactate dehydrogenase A. These results show that BPA directly promoted the proliferation, migration and invasion of ovarian cancer cells through the ERα/AKT/mTOR/HIF-1α signaling axis to enhance glycolysis.

Characterization of the effect of the GLUT-1 inhibitor BAY-876 on T cells and macrophages

Increased aerobic glycolysis is a metabolic hallmark of proinflammatory leukocytes including macrophages and T cells. To take up glucose from the environment and fuel glycolysis, activated leukocytes upregulate the glucose transporter GLUT1. The orally bioavailable selective GLUT1 inhibitor BAY-876 was developed primarily as an anti-tumor drug. Our study assessed its activity on activated macrophages and CD4⁺ T cells. BAY-876 significantly attenuated glucose uptake by cultured CD4⁺ T cells and macrophages by 41% and 15%, respectively. Extracellular flux analysis of activated CD4⁺ T cells in vitro showed that BAY-876 significantly decreases glycolytic proton flux rate and lactate production, effects that are accompanied by an increased oxidative phosphorylation-mediated ATP production rate, leaving intracellular ATP levels per cell unchanged. However, GLUT1 inhibition reduced CD4⁺ T cell proliferation without compromising cell viability and reduced IFN-γ secretion by 20%. Moreover, TNF secretion from macrophages was reduced by 27%. We conclude that GLUT1-specific inhibitors, like BAY-876, deserve further in vivo testing in a broad range of (auto-) inflammatory disease models.

Gallic acid markedly stimulates GLUT1-mediated glucose uptake by the AsPC-1 pancreatic cancer cell line

Phenolic acids are recognized as chemopreventive and chemotherapeutic agents. Altered glucose and glutamine metabolism are recognized hallmarks of cancer cells. We aimed to test the influence of phenolic acids on glucose and glutamine cellular uptake by a breast (MCF-7) and a pancreatic (AsPC-1) cancer cell line. Several phenolic acids (caffeic, ferrulic, proctocatechuic, coumaric and gallic acid) affected ³H-glutamine and/or ³H-deoxy-d-glucose (³H-DG) uptake. Gallic acid (100 µM) caused a 3-fold increase in ³H-DG uptake by AsPC-1 cells, associated with a 3.7-fold increase in lactic acid production. Gallic acid stimulated GLUT1-mediated ³H-DG uptake and increased the affinity of this transporter for ³H-DG. We further verified that gallic acid does not change GLUT1 transcription rates and cellular redox state and that its effect does not involve PI3K, mTOR and MAP kinases and is not associated with a proproliferative effect. Gallic acid also increased ³H-DG uptake by MCF-7 cells, although less potently. Further investigation is necessary to elucidate the cellular pathways involved in this effect of gallic acid.

Potential Therapies Targeting the Metabolic Reprogramming of Diabetes-Associated Breast Cancer

In recent years, diabetes-associated breast cancer has become a significant clinical challenge. Diabetes is not only a risk factor for breast cancer but also worsens its prognosis. Patients with diabetes usually show hyperglycemia and hyperinsulinemia, which are accompanied by different glucose, protein, and lipid metabolism disorders. Metabolic abnormalities observed in diabetes can induce the occurrence and development of breast cancer. The changes in substrate availability and hormone environment not only create a favorable metabolic environment for tumorigenesis but also induce metabolic reprogramming events required for breast cancer cell transformation. Metabolic reprogramming is the basis for the development, swift proliferation, and survival of cancer cells. Metabolism must also be reprogrammed to support the energy requirements of the biosynthetic processes in cancer cells. In addition, metabolic reprogramming is essential to enable cancer cells to overcome apoptosis signals and promote invasion and metastasis. This review aims to describe the major metabolic changes in diabetes and outline how cancer cells can use cellular metabolic changes to drive abnormal growth and proliferation. We will specifically examine the mechanism of metabolic reprogramming by which diabetes may promote the development of breast cancer, focusing on the role of glucose metabolism, amino acid metabolism, and lipid metabolism in this process and potential therapeutic targets. Although diabetes-associated breast cancer has always been a common health problem, research focused on finding treatments suitable for the specific needs of patients with concurrent conditions is still limited. Most studies are still currently in the pre-clinical stage and mainly focus on reprogramming the glucose metabolism. More research targeting the amino acid and lipid metabolism is needed.

Recent progress of amino acid transporters as a novel antitumor target

Glutamine transporters transport different amino acids for cell growth and metabolism. In tumor cells, glutamine transporters are often highly expressed and play a crucial role in their growth. By inhibiting the amino acid transport of these transporters, the growth of cancer cells can be inhibited. In recent years, more and more attention has been paid to the study of glutamine transporter. In this article, the differences between the ASC system amino acid transporter 2 (ASCT2), L-type amino acid transporter 1 (LAT1), and the cystine–glutamate exchange (xCT) transporters research progress on the mechanism of action and corresponding small molecule inhibitors are summarized. This article introduces 62 related small molecule inhibitors of different transporters of ASCT2, LAT1, and xCT. These novel chemical structures provide ideas for the research and design of targeted inhibitors of glutamine transporters, as well as important references and clues for the design of new anti-tumor drugs.

Pathological Significance of GLUT-1 Expression in Breast Cancer Cells in Diabetic and Obese Patients: The French Guiana Study

Simple Summary

This study describes the clinical, histological, and molecular features of breast cancer in French Guiana, and characterizes the expression of the tumor metabolic marker GLUT-1 in breast cancers cells in diabetic and obese patients compared to a control group. This study reveals an overall overexpression of GLUT-1 in 60% of invasive breast carcinomas and in all medullary pattern and carcinoma in situ lesions. Our results highlight the potential role of GLUT-1 as a tumor metabolic prognostic marker and also as an interesting target therapy, independently of patient metabolic disorder.

Abstract

The prevalence of obesity and type 2 diabetes is higher in French Guiana compared to mainland France. These metabolic disorders are associated with an increased risk of cancer. One of the factors involved is hyperinsulinemia that promotes the action of glucose transporter 1 (GLUT-1). The objective of this study is to characterize the expression of GLUT-1 in breast cancers cells in diabetic and obese patients compared to those who are not and to describe the clinical and histological prognostic factors of breast cancer in this population. We conducted a monocentric study including patients with breast cancer diagnosed between 2014 and 2020. Patients were classified into three groups: diabetes, obesity, and control group. The GLUT-1 expression was assessed by immunohistochemistry. In total, 199 patients were included in this study. The median age was 53.5 years, and the median tumor size was 2.8 cm. Luminal A was the most frequent molecular type (58.1%), followed by the triple-negative type (19.9%). The breast cancer in our population was characterized by a younger age at diagnosis, more aggressive molecular types, and larger tumor size. Thus, we suggest the advancement of the age of breast cancer screening in this territory. A total of 144 patients (31 diabetes, 22 obese, and 91 control group) were included for the study of GLUT-1 expression. Overexpression of GLUT-1 was observed in 60.4% of cases and in all carcinoma in situ lesions. GLUT-1 overexpression was associated with more aggressive cancers. This overexpression is correlated with high histological grade, high proliferation index, and aggressive molecular types. Our study found no difference in GLUT-1 expression between the diabetic or obese patients and the control group. These results highlight the potential role of GLUT-1 as a tumor metabolic prognostic marker and also as an interesting target therapy, independently of patient metabolic disorder.

The pro-proliferative effect of insulin in human breast epithelial DMBA-transformed and non-transformed cell lines is PI3K-, mTOR- and GLUT1-dependent

Type 2 diabetes mellitus (T2DM) is linked to an increased risk of breast cancer. We aimed to investigate how T2DM-associated characteristics (high levels of glucose, insulin, leptin, inflammatory mediators and oxidative stress) influence breast cancer carcinogenesis, in DMBA-treated (MCF-12A_DMBA ) and non-treated breast epithelial (MCF-12A) cell lines. Insulin (50 nM) promotes cell proliferation, ³ H-DG uptake and lactic acid production in both cell lines. The stimulatory effects of insulin upon cell proliferation and ³ H-DG uptake were hampered by rapamycin, LY294001 and BAY-876, in both cell lines. In conclusion, hyperinsulinemia, one important characteristic of T2DM, contributes to the initiation of breast cancer by a PI3K- and mTOR-dependent mechanism involving increased GLUT1-mediated glucose uptake. SIGNIFICANCE: The pro-proliferative effect of insulin in human breast epithelial DMBA-transformed and non-transformed cell lines is PI3K-, mTOR- and GLUT1-dependent.

A Novel Microcrystalline BAY-876 Formulation Achieves Long-Acting Antitumor Activity Against Aerobic Glycolysis and Proliferation of Hepatocellular Carcinoma

BAY-876 is an effective antagonist of the Glucose transporter type 1 (GLUT1) receptor, a mediator of aerobic glycolysis, a biological process considered a hallmark of hepatocellular carcinoma (HCC) together with cell proliferation, drug-resistance, and metastasis. However, the clinical application of BAY-876 has faced many challenges. In the presence study, we describe the formulation of a novel microcrystalline BAY-876 formulation. A series of HCC tumor models were established to determine not only the sustained release of microcrystalline BAY-876, but also its long-acting antitumor activity. The clinical role of BAY-876 was confirmed by the increased expression of GLUT1, which was associated with the worse prognosis among advanced HCC patients. A single dose of injection of microcrystalline BAY-876 directly in the HCC tissue achieved sustained localized levels of Bay-876. Moreover, the single injection of microcrystalline BAY-876 in HCC tissues not only inhibited glucose uptake and prolonged proliferation of HCC cells, but also inhibited the expression of epithelial-mesenchymal transition (EMT)-related factors. Thus, the microcrystalline BAY-876 described in this study can directly achieve promising localized effects, given its limited diffusion to other tissues, thereby reducing the occurrence of potential side effects, and providing an additional option for advanced HCC treatment.

The pro-proliferative effect of interferon-γ in breast cancer cell lines is dependent on stimulation of ASCT2-mediated glutamine cellular uptake

AIMS

Type 2 diabetes mellitus (T2DM) is a risk factor for breast cancer initiation and progression. Glutamine (GLN) is a critical nutrient for cancer cells. The aim of this study was to investigate the effect of T2DM-associated compounds upon GLN uptake by breast cancer cells.

MAIN METHODS

The in vitro uptake of ³H-GLN by breast cancer (MCF-7 and MDA-MB-231) and non-tumorigenic (MCF-12A) cell lines was measured.

KEY FINDINGS

³H-GLN uptake in the three cell lines is mainly Na⁺-dependent and sensitive to the ASCT2 inhibitor GPNA. IFN-γ increased total and Na⁺-dependent ³H-GLN uptake in the two breast cancer cell lines, and insulin increased total and Na⁺-dependent ³H-GLN uptake in the non-tumorigenic cell line. GPNA abolished the increase in ³H-GLN uptake promoted by these T2DM-associated compounds. ASCT2 knockdown confirmed that the increase in ³H-GLN uptake caused by IFN-γ (in breast cancer cells) and by insulin (in non-tumorigenic cells) is ASCT2-dependent. IFN-γ (in MDA-MB-231 cells) and insulin (in MCF-12A cells) increased ASCT2 transcript and protein levels. Importantly, the pro-proliferative effect of IFN-γ in breast cancer cell lines was associated with an increase in ³H-GLN uptake which was GPNA-sensitive, blocked by ASCT2 knockdown and mediated by activation of the PI3K-, STAT3- and STAT1 intracellular signalling pathways.

SIGNIFICANCE

IFN-γ and insulin possess pro-proliferative effects in breast cancer and non-cancer cell lines, respectively, which are dependent on an increase in ASCT2-mediated glutamine transport. Thus, an effective inhibition of ASCT2-mediated glutamine uptake may be a therapeutic strategy against human breast cancer in T2DM patients.