Leptin, Adiponectin, and Sam68 in Bone Metastasis from Breast Cancer

Bone marrow adipocytes and lung cancer bone metastasis: unraveling the role of adipokines in the tumor microenvironment

Bone is a common site of metastasis for lung cancer. The "seed and soil" hypothesis suggests that the bone marrow microenvironment ("soil") may provide a conducive survival environment for metastasizing tumor cells ("seeds"). The bone marrow microenvironment, comprising a complex array of cells, includes bone marrow adipocytes (BMAs), which constitute about 70% of the adult bone marrow volume and may play a significant role in tumor bone metastasis. BMAs can directly provide energy for tumor cells, promoting their proliferation and migration. Furthermore, BMAs participate in the tumor microenvironment's osteogenesis regulation, osteoclast(OC) regulation, and immune response through the secretion of adipokines, cytokines, and inflammatory factors. However, the precise mechanisms of BMAs in lung cancer bone metastasis remain largely unclear. This review primarily explores the role of BMAs and their secreted adipokines (leptin, adiponectin, Nesfatin-1, Resistin, chemerin, visfatin) in lung cancer bone metastasis, aiming to provide new insights into the mechanisms and clinical treatment of lung cancer bone metastasis.

A preliminary mechanistic exploration of the effect of leptin on the docetaxel sensitivity of MDA‑MB‑231 triple‑negative breast cancer cells

Breast cancer is a common tumor encountered in women, and triple-negative breast cancer (TNBC) has an extremely poor prognosis. The effect of leptin on the docetaxel sensitivity of MDA-MB-231 TNBC cells has not been investigated. The present study aimed to clarify the effect of leptin and M2 tumor-associated macrophages (TAMs) on the chemosensitivity of TNBC cell lines and its possible mechanisms. In the present study, the apoptosis of the MDA-MB-231 cell line was detected at 0, 24, 48 and 72 h using a Cell Counting Kit-8 assay to determine the appropriate concentration of docetaxel as well as the IC50 value. After determining the effect of leptin on TAMs, the conditioned medium with an appropriate concentration of docetaxel was collected to treat the breast cancer cells, and flow cytometry was used to detect the cell cycle distribution and apoptosis in different treatment groups. Interleukin 8 (IL-8) expression was detected using ELISA and western blot assay. The IL-8 antibody was used to neutralize IL-8, and invasion and scratch assays were used to detect changes in invasion and migration of breast cancer cells. Statistical analysis was performed using GraphPad Prism 9.0 and SPSS 22.0. It was revealed that the apoptotic rate of MDA-MB-231 cells in the leptin-treated TAMs group was lower than that in other groups. The expression of IL-8 was notably elevated in the group treated with leptin-activated TAMs compared with that in the other groups. The neutralization of IL-8 resulted in a significant reduction in the invasive migration of MDA-MB-231 cells compared with that in the non-neutralized group.

Metabolic underpinnings of cancer-related fatigue

Cancer-related fatigue (CRF) is one of the most prevalent and detrimental complications of cancer. Emerging evidence suggests that obesity and insulin resistance are associated with CRF occurrence and severity in cancer patients and survivors. In this narrative review, we analyzed recent studies including both preclinical and clinical research on the relationship between obesity and/or insulin resistance and CRF. We also describe potential mechanisms for these relationships, though with the caveat that because the mechanisms underlying CRF are incompletely understood, the mechanisms mediating the association between obesity/insulin resistance and CRF are similarly incompletely delineated. The data suggest that, in addition to their effects to worsen CRF by directly promoting tumor growth and metastasis, obesity and insulin resistance may also contribute to CRF by inducing chronic inflammation, neuroendocrinological disturbance, and metabolic alterations. Furthermore, studies suggest that patients with obesity and insulin resistance experience more cancer-induced pain and are at more risk of emotional and behavioral disruptions correlated with CRF. However, other studies implied a potentially paradoxical impact of obesity and insulin resistance to reduce CRF symptoms. Despite the need for further investigation utilizing interventions to directly elucidate the mechanisms of cancer-related fatigue, current evidence demonstrates a correlation between obesity and/or insulin resistance and CRF, and suggests potential therapeutics for CRF by targeting obesity and/or obesity-related mediators.

Subcutaneous fat predicts bone metastasis in breast cancer: A novel multimodality-based deep learning model

OBJECTIVES

This study explores a deep learning (DL) approach to predicting bone metastases in breast cancer (BC) patients using clinical information, such as the fat index, and features like Computed Tomography (CT) images.

METHODS

CT imaging data and clinical information were collected from 431 BC patients who underwent radical surgical resection at Harbin Medical University Cancer Hospital. The area of muscle and adipose tissue was obtained from CT images at the level of the eleventh thoracic vertebra. The corresponding histograms of oriented gradients (HOG) and local binary pattern (LBP) features were extracted from the CT images, and the network features were derived from the LBP and HOG features as well as the CT images through deep learning (DL). The combination of network features with clinical information was utilized to predict bone metastases in BC patients using the Gradient Boosting Decision Tree (GBDT) algorithm. Regularized Cox regression models were employed to identify independent prognostic factors for bone metastasis.

RESULTS

The combination of clinical information and network features extracted from LBP features, HOG features, and CT images using a convolutional neural network (CNN) yielded the best performance, achieving an AUC of 0.922 (95% confidence interval [CI]: 0.843-0.964, P< 0.01). Regularized Cox regression results indicated that the subcutaneous fat index was an independent prognostic factor for bone metastasis in breast cancer (BC).

CONCLUSION

Subcutaneous fat index could predict bone metastasis in BC patients. Deep learning multimodal algorithm demonstrates superior performance in assessing bone metastases in BC patients.

Role of bone marrow adipocytes in bone metastasis development and progression: a systematic review

Purpose

Bone marrow adipocytes (BMAs) are the most plentiful cells in the bone marrow and function as an endocrine organ by producing fatty acids, cytokines, and adipokines. Consequently, BMAs can interact with tumor cells, influencing both tumor growth and the onset and progression of bone metastasis. This review aims to systematically evaluate the role of BMAs in the development and progression of bone metastasis.

Methods

A comprehensive search was conducted on PubMed, Web of Science, and Scopus electronic databases, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement standards, to identify studies published from March 2013 to June 2023. Two independent reviewers assessed and screened the literature, extracted the data, and evaluated the quality of the studies. The body of evidence was evaluated and graded using the ROBINS-I tool for non-randomized studies of interventions and the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE) tool for in vivo studies. The results were synthesized using descriptive methods.

Results

The search yielded a total of 463 studies, of which 17 studies were included in the final analysis, including 15 preclinical studies and two non-randomized clinical studies. Analysis of preclinical studies revealed that BMAs play a significant role in bone metastasis, particularly in prostate cancer followed by breast and malignant melanoma cancers. BMAs primarily influence cancer cells by inducing a glycolytic phenotype and releasing or upregulating soluble factors, chemokines, cytokines, adipokines, tumor-derived fatty acid-binding protein (FABP), and members of the nuclear receptor superfamily, such as chemokine (C-C motif) ligand 7 (CCL7), C-X-C Motif Chemokine Ligand (CXCL)1, CXCL2, interleukin (IL)-1β, IL-6, FABP4, and peroxisome proliferator-activated receptor γ (PPARγ). These factors also contribute to adipocyte lipolysis and regulate a pro-inflammatory phenotype in BMAs. However, the number of clinical studies is limited, and definitive conclusions cannot be drawn.

Conclusion

The preclinical studies reviewed indicate that BMAs may play a crucial role in bone metastasis in prostate, breast, and malignant melanoma cancers. Nevertheless, further preclinical and clinical studies are needed to better understand the complex role and relationship between BMAs and cancer cells in the bone microenvironment. Targeting BMAs in combination with standard treatments holds promise as a potential therapeutic strategy for bone metastasis.

Validating Sam68 expression and protein level in breast cancer

Breast carcinoma ranks as the second most common cancer among women worldwide. Despite significant therapeutic advancements, approximately 25% of breast carcinoma cases have resistance to current treatment modalities, posing a significant challenge for patient management. This study aimed to investigate the role of Sam68 mRNA and its protein in promoting oncogenesis and breast cancer progression. Sam68 protein levels were assessed in tissue samples using an Enzyme-Linked Immunosorbent Assay kit from Sun Long Biotech. Whole RNA was isolated from malignant breast tissue samples obtained from patients. The RNA concentration was determined using an Eppendorf photometer, yielding an average concentration of 62.1±10.07 ng/µl. The purity of the isolated RNA was evaluated by measuring the A260/A280 ratio (1.9±0.07) and the A260/A230 ratio (1.7±0.3). The results indicated a significant upregulation of Sam68 mRNA expression in breast cancer tissues, supporting the findings from previous studies and indicating the correlation between altered Sam68 expression and the development of breast carcinoma, highlighting the potential significance of Sam68 in the pathogenesis of the disease. Estimating Sam68 in the blood may serve as a potential biomarker for assessing the malignant grade and metastatic spread of breast carcinoma cells.

Lower subcutaneous fat index predicts bone metastasis in breast cancer

BACKGROUND

Bone metastases affect 50% to 70% of breast cancer (BC) patients and have a high mortality rate. Adipose tissue loss plays a pivotal role in the progression of cancer.

OBJECTIVE

This study aims to evaluate the prognostic value of adipose tissue for bone metastasis in BC patients.

METHODS

517 BC patients were studied retrospectively. Patients' characteristics before the surgery were collected. Quantitative measurements of the subcutaneous fat index (SFI) were performed at the level of the eleventh thoracic vertebra. In order to adjust for the heterogeneity between the low SFI and high SFI groups, propensity score matching (PSM) was used. The Kaplan-Meier method was used to estimate the 5-year bone metastatic incidence. The prognostic analysis was performed with the Cox regression models.

RESULTS

Compared with the patients without bone metastasis, the patients with bone metastasis had reduced SFI levels. In addition, Kaplan-Meier analysis revealed that patients with low SFI were more likely to develop bone metastases. The independent predictive value of SFI for bone metastases was confirmed by Cox regression analysis. The survival analysis was repeated after PSM with a 1:1 ratio, yielding similar results (P< 0.05).

CONCLUSIONS

SFI is an independent predictor of bone metastasis in BC patients.

The impact of leptin and its receptor polymorphisms on type 1 diabetes in a population of northwest Iran

BACKGROUND

Diabetes comprises a serious disease with significant growth in the number of cases in recent years. Here, we cover the gap in information between leptin (LEP) and type 1 diabetes in the Iranian population.

AIM

To recognise LEP G2548A and LEP receptor Q223R polymorphisms in Iranian people and their association with type 1 diabetes susceptibility.

SUBJECTS AND METHODS

Characteristics such as fasting blood sugar (FBS) were measured in 80 control non-diabetic individuals and 89 diabetic patients. Moreover, LEP G2548A and LEP receptor Q223R polymorphisms were genotyped using polymerase chain reaction-restriction fragment length polymorphism technique.

RESULTS

The frequency of the A allele was nearly three times greater in diabetes patients than in the control group. In addition, in the diabetes group, the AA genotype was five times greater than in the control group (p < 0.01). Furthermore, AA and AA + AG genotype models had higher FBS levels than the GG + AG and GG genotype models, respectively (p < 0.01).

CONCLUSION

The LEP G2548A polymorphism could be related to type 1 diabetes susceptibility, but not LEPR Q223R polymorphism in the Iranian population. Importantly, further studies are essential to examine the impact of LEP G2548A and LEPR Q223R polymorphisms in the endocrinology area.

Hepatic Sam68 Regulates Systemic Glucose Homeostasis and Insulin Sensitivity

Hepatic glucose production (HGP) is an important component of glucose homeostasis, and deregulated HGP, particularly through gluconeogenesis, contributes to hyperglycemia and pathology of type-2 diabetes (T2D). It has been shown that the gluconeogenic gene expression is governed primarily by the transcription factor cAMP-response element (CRE)-binding protein (CREB) and its coactivator, CREB-regulated transcriptional coactivator 2 (CRTC2). Recently, we have discovered that Sam68, an adaptor protein and Src kinase substrate, potently promotes hepatic gluconeogenesis by promoting CRTC2 stability; however, the detailed mechanisms remain unclear. Here we show that in response to glucagon, Sam68 increases CREB/CRTC2 transactivity by interacting with CRTC2 in the CREB/CRTC2 complex and occupying the CRE motif of promoters, leading to gluconeogenic gene expression and glucose production. In hepatocytes, glucagon promotes Sam68 nuclear import, whereas insulin elicits its nuclear export. Furthermore, ablation of Sam68 in hepatocytes protects mice from high-fat diet (HFD)-induced hyperglycemia and significantly increased hepatic and peripheral insulin sensitivities. Thus, hepatic Sam68 potentiates CREB/CRTC2-mediated glucose production, contributes to the pathogenesis of insulin resistance, and may serve as a therapeutic target for T2D.

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.

Distinct Metabolism of Bone Marrow Adipocytes and their Role in Bone Metastasis

Bone marrow adipocytes (BMAs) represent 10% of the total fat mass of the human body and serve as an energy reservoir for the skeletal niche. They function as an endocrine organ by actively secreting fatty acids, cytokines, and adipokines. The volume of BMAs increases along with age, osteoporosis and/or obesity. With the rapid development of multi-omic analysis and the advance in in vivo imaging technology, further distinct characteristics and functions of BMAs have been revealed. There is accumulating evidence that BMAs are metabolically, biologically and functionally unique from white, brown, beige and pink adipocytes. Bone metastatic disease is an uncurable complication in cancer patients, where primary cancer cells spread from their original site into the bone marrow. Recent publications have highlighted those BMAs could also serve as a rich lipid source of fatty acids that can be utilized by the cancer cells during bone metastasis, particularly for breast, prostate, lung, ovarian and pancreatic cancer as well as melanoma. In this review, we summarize the novel progressions in BMAs metabolism, especially with multi-omic analysis and in vivo imaging technology. We also update the metabolic role of BMAs in bone metastasis, and their potential new avenues for diagnosis and therapies against metastatic cancers.

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.

Multi‑faceted role of cancer‑associated adipocytes in the tumor microenvironment (Review)

Adipocytes are a type of stromal cell found in numerous different tissues that serve an active role in the tumor microenvironment. Cancer-associated adipocytes (CAAs) display a malignant phenotype and are found at the invasive tumor front, which mediates the crosstalk network between adipocytes (the precursor cells that will become cancer-associated adipocytes in the future) and cancer cells. The present review covers the mechanisms of adipocytes in the development of cancer, including metabolic reprogramming, chemotherapy resistance and adipokine regulation. Furthermore, the potential mechanisms involved in the adipocyte-cancer cell cycle in various types of cancer, including breast, ovarian, colon and rectal cancer, are discussed. Deciphering the complex network of CAA-cancer cell crosstalk will provide insights into tumor biology and optimize therapeutic strategies.

Another Weapon against Cancer and Metastasis: Physical-Activity-Dependent Effects on Adiposity and Adipokines

Physically active behavior has been associated with a reduced risk of developing certain types of cancer and improved psychological conditions for patients by reducing anxiety and depression, in turn improving the quality of life of cancer patients. On the other hand, the correlations between inactivity, sedentary behavior, and overweight and obesity with the risk of development and progression of various cancers are well studied, mainly in middle-aged and elderly subjects. In this article, we have revised the evidence on the effects of physical activity on the expression and release of the adipose-tissue-derived mediators of low-grade chronic inflammation, i.e., adipokines, as well as the adipokine-mediated impacts of physical activity on tumor development, growth, and metastasis. Importantly, exercise training may be effective in mitigating the side effects related to anti-cancer treatment, thereby underlining the importance of encouraging cancer patients to engage in moderate-intensity activities. However, the strong need to customize and adapt exercises to a patient’s abilities is apparent. Besides the preventive effects of physically active behavior against the adipokine-stimulated cancer risk, it remains poorly understood how physical activity, through its actions as an adipokine, can actually influence the onset and development of metastases.

Leptin, Leptin Receptor, KHDRBS1 (KH RNA Binding Domain Containing, Signal Transduction Associated 1), and Adiponectin in Bone Metastasis from Breast Carcinoma: An Immunohistochemical Study

Breast cancer patients are at a high risk of complications from bone metastasis. Molecular characterization of bone metastases is essential for the discovery of new therapeutic targets. Here, we investigated the expression and the intracellular distribution of KH RNA binding domain containing, signal transduction associated 1 (KHDRBS1), leptin, leptin receptor (LEPR), and adiponectin in bone metastasis from breast carcinoma and looked for correlations between the data. The expression of these proteins is known in breast carcinoma, but it has not been investigated in bone metastatic tissue to date. Immunohistochemical analysis was carried out on bone metastasis specimens, then semiquantitative evaluation of the results and the Pearson test were performed to determine eventual correlations. KHDRBS1 expression was significantly higher in the nuclei than in the cytosol of metastatic cells; LEPR was prevalently observed in the cytosol and the nuclei; leptin and adiponectin were found in metastatic cells and stromal cells; the strongest positive correlation was between nuclear KHDRBS1 and nuclear LEPR expression. Taken together, our findings support the importance of the leptin/LEPR/KHDRBS1 axis and of adiponectin in the progression of bone metastasis and suggest their potential application in pharmacological interventions.

Bone Marrow Adipocytes, Adipocytokines, and Breast Cancer Cells: Novel Implications in Bone Metastasis of Breast Cancer

Accumulating discoveries highlight the importance of interaction between marrow stromal cells and cancer cells for bone metastasis. Bone is the most common metastatic site of breast cancer and bone marrow adipocytes (BMAs) are the most abundant component of the bone marrow microenvironment. BMAs are unique in their origin and location, and recently they are found to serve as an endocrine organ that secretes adipokines, cytokines, chemokines, and growth factors. It is reasonable to speculate that BMAs contribute to the modification of bone metastatic microenvironment and affecting metastatic breast cancer cells in the bone marrow. Indeed, BMAs may participate in bone metastasis of breast cancer through regulation of recruitment, invasion, survival, colonization, proliferation, angiogenesis, and immune modulation by their production of various adipocytokines. In this review, we provide an overview of research progress, focusing on adipocytokines secreted by BMAs and their potential roles for bone metastasis of breast cancer, and investigating the mechanisms mediating the interaction between BMAs and metastatic breast cancer cells. Based on current findings, BMAs may function as a pivotal modulator of bone metastasis of breast cancer, therefore targeting BMAs combined with conventional treatment programs might present a promising therapeutic option.

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.

Intratumoral Adipocyte-High Breast Cancer Enrich for Metastatic and Inflammation-Related Pathways but Associated with Less Cancer Cell Proliferation

Cancer-associated adipocytes are known to cause inflammation, leading to cancer progression and metastasis. The clinicopathological and transcriptomic data from 2256 patients with breast cancer were obtained based on three cohorts: The Cancer Genome Atlas (TCGA), GSE25066, and a study by Yau et al. For the current study, we defined the adipocyte, which is calculated by utilizing a computational algorithm, xCell, as “intratumoral adipocyte”. These intratumoral adipocytes appropriately reflected mature adipocytes in a bulk tumor. The amount of intratumoral adipocytes demonstrated no relationship with survival. Intratumoral adipocyte-high tumors significantly enriched for metastasis and inflammation-related gene sets and are associated with a favorable tumor immune microenvironment, especially in the ER+/HER2- subtype. On the other hand, intratumoral adipocyte-low tumors significantly enriched for cell cycle and cell proliferation-related gene sets. Correspondingly, intratumoral adipocyte-low tumors are associated with advanced pathological grades and inversely correlated with MKI67 expression. In conclusion, a high amount of intratumoral adipocytes in breast cancer was associated with inflammation, metastatic pathways, cancer stemness, and favorable tumor immune microenvironment. However, a low amount of adipocytes was associated with a highly proliferative tumor in ER-positive breast cancer. This cancer biology may explain the reason why patient survival did not differ by the amount of adipocytes.

Pre-Operative Combination of Normal BMI with Elevated YKL-40 and Leptin but Lower Adiponectin Level Is Linked to a Higher Risk of Breast Cancer Relapse: A Report of Four-Year Follow-Up Study

Adipokines are powerful agents involved in the development of obesity-dependent cancers. This prospective study aimed to investigate the association between pre-treatment body mass index (BMI) and serum YKL-40, leptin, and adiponectin concentrations as well as the plasma activity of tissue factor (TF) and the future prognosis of early, non-metastatic breast cancer (BrC) subjects. The serum levels of YKL-40, leptin, and adiponectin as well as plasma TF activity, anthropometric parameters, and clinicopathological parameters were analysed in 81 treatment-naïve females with invasive BrC. The predictive value of YKL-40, BMI, leptin, adiponectin, and TF was determined with a 95% confidence interval (CI). Kaplan–Meier plots and log-rank and F Cox tests were used to determine the clinical outcomes of progression-free survival (PFS). The median follow-up duration was 44 months with complete follow-up for the first event. Follow-up revealed a significantly higher incidence of disease relapse in BrC patients with a high baseline concentration of YKL-40 (22.22%) and TF activity (21.43%). Body mass index was an independent predictor of survival, with women who were overweight/obese being less prone to relapse (hazard ratio (HR): 0.75; 95% CI: 0.59 to 0.95). The recurrence rates for normal-weight BrC cases was 21.05% versus 7.14% for their overweight counterparts. The receiver operating characteristic analysis showed the strong ability of the analysed biomarkers to predict disease progression, with an area under the receiver operating characteristics (ROC) curve of 0.84 (95% CI, 0.823 to 0.931). In a prospective cohort of invasive BrC patients, overweight/obesity was associated with improved future outcomes. The combination of a normal BMI with high leptin and low adiponectin levels and high TF activity was associated with an increased risk of recurrence and decreased survival.

Diallyl Trisulfide Inhibits Leptin-induced Oncogenic Signaling in Human Breast Cancer Cells but Fails to Prevent Chemically-induced Luminal-type Cancer in Rats

Previous studies have demonstrated inhibitory effect of garlic component diallyl trisulfide (DATS) on growth of breast cancer cells in vitro and in vivo. This study investigated the effect of DATS on oncogenic signaling regulated by leptin, which plays an important role in breast carcinogenesis. Leptin-induced phosphorylation and nuclear translocation of STAT3 was inhibited significantly in the presence of DATS in MCF-7 (a luminal-type human breast cancer cell line) and MDA-MB-231 (a basal-like human breast cancer cell line). Leptin-stimulated cell proliferation, clonogenic cell survival, and migration and/or invasion ability in MCF-7 and/or MDA-MB-231 cells were also suppressed by DATS treatment. DATS exposure resulted in inhibition of leptin-stimulated expression of protein and/or mRNA levels of Bcl-2, Bcl-xL, Cyclin D1, vascular endothelial growth factor, and matrix metalloproteinase-2. Western blotting revealed a decrease in protein levels of phosphorylated STAT3 in breast cancer xenografts from DATS-treated mice when compared to controls in vivo. However, the incidence of N-methyl-N-nitrosourea-induced luminal-type breast cancer development in rats was not affected by oral administration of 5 mg/kg or 25 mg/kg DATS. The present study reveals that oncogenic signaling induced by leptin is inhibited in the presence of DATS but higher doses of this phytochemical may be required to achieve chemopreventive activity.