Aspalathus linearis (Rooibos) Targets Adipocytes and Obesity-Associated Inflammation.

Excess weight and obesity are the fifth leading cause of death globally, and sustained efforts from health professionals and researchers are required to mitigate this pandemic-scale problem. Polyphenols and flavonoids found in Aspalathus linearis-a plant widely consumed as Rooibos tea-are increasingly being investigated for their positive effects on various health issues including inflammation. The aim of our study was to examine the effect of Rooibos extract on obesity and the associated low-grade chronic inflammatory state by testing antioxidant activity, cytokine secretions, macrophage polarization and the differentiation of human adipocytes through the development of adipospheroids. Rooibos extract significantly decreased ROS production and the secretion of pro-inflammatory cytokines (IFN-γ, IL-12, IL-2 and IL-17a) in human leukocytes. Additionally, Rooibos extract down-regulated LPS-induced macrophage M1 polarization, shown by a significant decrease in the expression of pro-inflammatory cytokines: TNFα, IL-8, IL-6, IL-1ß and CXCL10. In addition, Rooibos inhibited intracellular lipid accumulation and reduced adipogenesis by decreasing the expression of PPARγ, Ap2 and HSL in adipospheroids. A significant decrease in leptin expression was noted and this, more interestingly, was accompanied by a significant increase in adiponectin expression. Using a co-culture system between macrophages and adipocytes, Rooibos extract significantly decreased the expression of all studied pro-inflammatory cytokines and particularly leptin, and increased adiponectin expression. Thus, adding Rooibos tea to the daily diet is likely to prevent the development of obesity associated with chronic low-level inflammation.

A bicellular fluorescent ductal carcinoma in situ (DCIS)-like tumoroid to study the progression of carcinoma: practical approaches and optimization.

Recently, many types of 3D culture systems have been developed to preserve the physicochemical environment and biological characteristics of the original tumors better than the conventional 2D monolayer culture system. There are various types of models belonging to this culture, such as the culture based on non-adherent and/or scaffold-free matrices to form the tumors. Agarose mold has been widely used to facilitate tissue spheroid assembly, as it is essentially non-biodegradable, bio-inert, biocompatible, low-cost, and low-attachment material that can promote cell spheroidization. As no studies have been carried out on the development of a fluorescent bicellular tumoroid mimicking ductal carcinoma in situ (DCIS) using human cell lines, our objective was to detail the practical approaches developed to generate this model, consisting of a continuous layer of myoepithelial cells (MECs) around a previously formed in situ breast tumor. The practical approaches developed to generate a bi-cellular tumoroid mimicking ductal carcinoma in situ (DCIS), consisting of a continuous layer of myoepithelial cells (MECs) around a previously formed in situ breast tumoroid. Firstly, the optimal steps and conditions of spheroids generation using a non-adherent agarose gel were described, in particular, the appropriate medium, seeding density of each cell type and incubation period. Next, a lentiviral transduction approach to achieve stable fluorescent protein expression (integrative system) was used to characterize the different cell lines and to track tumoroid generation through immunofluorescence, the organization of the two cell types was validated, specific merits and drawbacks were compared to lentiviral transduction. Two lentiviral vectors expressing either EGFP (Enhanced Green Fluorescent Protein) or m-Cherry (Red Fluorescent Protein) were used. Various rates of a multiplicity of infection (MOI) and multiple types of antibodies (anti-p63, anti-CK8, anti-Maspin, anti-Calponin) for immunofluorescence analysis were tested to determine the optimal conditions for each cell line. At MOI 40 (GFP) and MOI 5 (m-Cherry), the signals were almost homogeneously distributed in the cells which could then be used to generate the DCIS-like tumoroids. Images of the tumoroids in agarose molds were captured with a confocal microscope Micro Zeiss Cell Observer Spinning Disk or with IncuCyte® to follow the progress of the generation. Measurement of protumoral cytokines such as IL-6, IL8 and leptin confirmed their secretion in the supernatants, indicating that the properties of our cells were not altered. Finally the advantages and disadvantages of each fluorescent approach were discussed. This model could also be used for other solid malignancies to study the complex relationship between different cells such as tumor and myoepithelial cells in various microenvironments (inflammatory, adipose and tumor, obesity, etc.). Although, this new model is well established to monitor drug screening applications and perform pharmacokinetic and pharmacodynamic analyses.

Crosstalk of Inflammatory Cytokines within the Breast Tumor Microenvironment.

Several immune and immunocompetent cells, including dendritic cells, macrophages, adipocytes, natural killer cells, T cells, and B cells, are significantly correlated with the complex discipline of oncology. Cytotoxic innate and adaptive immune cells can block tumor proliferation, and others can prevent the immune system from rejecting malignant cells and provide a favorable environment for tumor progression. These cells communicate with the microenvironment through cytokines, a chemical messenger, in an endocrine, paracrine, or autocrine manner. These cytokines play an important role in health and disease, particularly in host immune responses to infection and inflammation. They include chemokines, interleukins (ILs), adipokines, interferons, colony-stimulating factors (CSFs), and tumor necrosis factor (TNF), which are produced by a wide range of cells, including immune cells, such as macrophages, B-cells, T-cells, and mast cells, as well as endothelial cells, fibroblasts, a variety of stromal cells, and some cancer cells. Cytokines play a crucial role in cancer and cancer-related inflammation, with direct and indirect effects on tumor antagonistic or tumor promoting functions. They have been extensively researched as immunostimulatory mediators to promote the generation, migration and recruitment of immune cells that contribute to an effective antitumor immune response or pro-tumor microenvironment. Thus, in many cancers such as breast cancer, cytokines including leptin, IL-1B, IL-6, IL-8, IL-23, IL-17, and IL-10 stimulate while others including IL-2, IL-12, and IFN-γ, inhibit cancer proliferation and/or invasion and enhance the body's anti-tumor defense. Indeed, the multifactorial functions of cytokines in tumorigenesis will advance our understanding of cytokine crosstalk pathways in the tumor microenvironment, such as JAK/STAT, PI3K, AKT, Rac, MAPK, NF-κB, JunB, cFos, and mTOR, which are involved in angiogenesis, cancer proliferation and metastasis. Accordingly, targeting and blocking tumor-promoting cytokines or activating and amplifying tumor-inhibiting cytokines are considered cancer-directed therapies. Here, we focus on the role of the inflammatory cytokine system in pro- and anti-tumor immune responses, discuss cytokine pathways involved in immune responses to cancer and some anti-cancer therapeutic applications.

Targeting Adiponectin in Breast Cancer.

Obesity and breast cancer are two major health issues that could be categorized as sincere threats to human health. In the last few decades, the relationship between obesity and cancer has been well established and extensively investigated. There is strong evidence that overweight and obesity increase the risk of postmenopausal breast cancer, and adipokines are the central players in this relationship. Produced and secreted predominantly by white adipose tissue, adiponectin is a bioactive molecule that exhibits numerous protective effects and is considered the guardian angel of adipokine. In the obesity-cancer relationship, more and more evidence shows that adiponectin may prevent and protect individuals from developing breast cancer. Recently, several updates have been published on the implication of adiponectin in regulating tumor development, progression, and metastases. In this review, we provide an updated overview of the metabolic signaling linking adiponectin and breast cancer in all its stages. On the other hand, we critically summarize all the available promising candidates that may reactivate these pathways mainly by targeting adiponectin receptors. These molecules could be synthetic small molecules or plant-based proteins. Interestingly, the advances in genomics have made it possible to create peptide sequences that could specifically replace human adiponectin, activate its receptor, and mimic its function. Thus, the obvious anti-cancer activity of adiponectin on breast cancer should be better exploited, and adiponectin must be regarded as a serious biomarker that should be targeted in order to confront this threatening disease.

The Impact of Obesity, Adipose Tissue, and Tumor Microenvironment on Macrophage Polarization and Metastasis.

Tumor metastasis is a major cause of death in cancer patients. It involves not only the intrinsic alterations within tumor cells, but also crosstalk between these cells and components of the tumor microenvironment (TME). Tumorigenesis is a complex and dynamic process, involving the following three main stages: initiation, progression, and metastasis. The transition between these stages depends on the changes within the extracellular matrix (ECM), in which tumor and stromal cells reside. This matrix, under the effect of growth factors, cytokines, and adipokines, can be morphologically altered, degraded, or reorganized. Many cancers evolve to form an immunosuppressive TME locally and create a pre-metastatic niche in other tissue sites. TME and pre-metastatic niches include myofibroblasts, immuno-inflammatory cells (macrophages), adipocytes, blood, and lymphatic vascular networks. Several studies have highlighted the adipocyte-macrophage interaction as a key driver of cancer progression and dissemination. The following two main classes of macrophages are distinguished: M1 (pro-inflammatory/anti-tumor) and M2 (anti-inflammatory/pro-tumor). These cells exhibit distinct microenvironment-dependent phenotypes that can promote or inhibit metastasis. On the other hand, obesity in cancer patients has been linked to a poor prognosis. In this regard, tumor-associated adipocytes modulate TME through the secretion of inflammatory mediators, which modulate and recruit tumor-associated macrophages (TAM). Hereby, this review describes the cellular and molecular mechanisms that link inflammation, obesity, and cancer. It provides a comprehensive overview of adipocytes and macrophages in the ECM as they control cancer initiation, progression, and invasion. In addition, it addresses the mechanisms of tumor anchoring and recruitment for M1, M2, and TAM macrophages, specifically highlighting their origin, classification, polarization, and regulatory networks, as well as their roles in the regulation of angiogenesis, invasion, metastasis, and immunosuppression, specifically highlighting the role of adipocytes in this process.

3D Cell Culture Systems: Tumor Application, Advantages, and Disadvantages.

The traditional two-dimensional (2D) in vitro cell culture system (on a flat support) has long been used in cancer research. However, this system cannot be fully translated into clinical trials to ideally represent physiological conditions. This culture cannot mimic the natural tumor microenvironment due to the lack of cellular communication (cell-cell) and interaction (cell-cell and cell-matrix). To overcome these limitations, three-dimensional (3D) culture systems are increasingly developed in research and have become essential for tumor research, tissue engineering, and basic biology research. 3D culture has received much attention in the field of biomedicine due to its ability to mimic tissue structure and function. The 3D matrix presents a highly dynamic framework where its components are deposited, degraded, or modified to delineate functions and provide a platform where cells attach to perform their specific functions, including adhesion, proliferation, communication, and apoptosis. So far, various types of models belong to this culture: either the culture based on natural or synthetic adherent matrices used to design 3D scaffolds as biomaterials to form a 3D matrix or based on non-adherent and/or matrix-free matrices to form the spheroids. In this review, we first summarize a comparison between 2D and 3D cultures. Then, we focus on the different components of the natural extracellular matrix that can be used as supports in 3D culture. Then we detail different types of natural supports such as matrigel, hydrogels, hard supports, and different synthetic strategies of 3D matrices such as lyophilization, electrospiding, stereolithography, microfluid by citing the advantages and disadvantages of each of them. Finally, we summarize the different methods of generating normal and tumor spheroids, citing their respective advantages and disadvantages in order to obtain an ideal 3D model (matrix) that retains the following characteristics: better biocompatibility, good mechanical properties corresponding to the tumor tissue, degradability, controllable microstructure and chemical components like the tumor tissue, favorable nutrient exchange and easy separation of the cells from the matrix.

Anti-Inflammatory and Cytotoxic Potential of New Phenanthrenoids from Luzula Sylvatica.

Phenanthrenoids have been widely described, in the Juncaceae family, for theirbiological properties such as antitumor, anxiolytic, anti-microbial, spasmolytic, and antiinflammatoryactivities. The Juncaceae family is known to contain a large variety ofphenanthrenoids possessing especially anti-inflammatory and cytotoxic properties. Luzulasylvatica, a Juncaceae species, is widely present in the Auvergne region of France, but has neverbeen studied neither for its phytochemical profile nor for its biological properties. We investigatedthe phytochemical profile and evaluated the potential anti-inflammatory activities of L. sylvaticaaerial parts extracts. A bioassay-guided fractionation was carried out to identify the most activefractions. Nine compounds were isolated, one coumarin 1 and eight phenanthrene derivatives (2-9), including four new compounds (4, 5, 8 and 9), from n-hexane and CH2Cl2, fractions. Theirstructures were established by HRESIMS, 1D and 2D NMR experiments. The biological properties,especially the anti-inflammatory/antioxidant activities (ROS production) and antiproliferativeactivity on THP-1, a monocytic leukemia cell line, of each compound, were evaluated. Threephenanthrene derivatives 4, 6, and 7 showed very promising antiproliferative activities.Phenanthrene derivatives.

Synthesis and Biological Evaluation of New Naphthoquinones Derivatives.

New substituted 1,4-naphthoquinones have been prepared in good overall yields through the naphthol route. The cytotoxicity of these compounds was tested in vitro on MCF-7 breast tumor cells. The most active compound 14 displayed an IC50 of 15µM. OBJECTIVE: To investigate the cytotoxicity of new naphthoquinones derivatives on MCF-7 cells. METHODS: Synthesis of new naphtoquinones derivatives and in vitro evaluation of their cytotoxicity on MCF-7 cells (rezasurin cell-based assay). RESULTS: Starting from Ethyl 4-hydroxy-6,7-dimethoxy-2-naphthoate, four naphthoquinones were prepared and exhibited substantial cytotoxicity against MCF-7 cells. CONCLUSION: Preliminary studies of the structure-activity relationship have shown the influence of the structural parameters and, in particular, the nature of the naphthoquinone side chain.

The Adipose Microenvironment Dysregulates the Mammary Myoepithelial Cells and Could Participate to the Progression of Breast Cancer.

Breast cancer is the most common cancer among women worldwide. Overweight and obesity are now recognized as established risk factors for this pathology in postmenopausal women. These conditions are also believed to be responsible for higher recurrence and mortality rates. Reciprocal interactions have been described between adipose and cancer cells. An adipose microenvironment favors a greater proliferation of cancer cells, their invasion and even resistance to anti-cancer treatments. In addition, the chronic low-grade inflammation observed in obese individuals is believed to amplify these processes. Among the cell types present in the breast, myoepithelial cells (MECs), located at the interface of the epithelial cells and the stroma, are considered "tumor suppressor" cells. During the transition from ductal carcinoma in situ to invasive cancer, disorganization or even the disappearance of MECs is observed, thereby enhancing the ability of the cancer cells to migrate. As the adipose microenvironment is now considered as a central actor in the progression of breast cancer, our objective was to evaluate if it could be involved in MEC functional modifications, leading to the transition of in situ to invasive carcinoma, particularly in obese patients. Through a co-culture model, we investigated the impact of human adipose stem cells from women of normal weight and obese women, differentiated or not into mature adipocytes, on the functionality of the MECs by measuring changes in viability, apoptosis, gene, and miRNA expressions. We found that adipose cells (precursors and differentiated adipocytes) could decrease the viability of the MECs, regardless of the original BMI. The adipose cells could also disrupt the expression of the genes involved in the maintenance of the extracellular matrix and to amplify the expression of leptin and inflammatory markers. miR-122-5p and miR-132-3p could also be considered as targets for adipose cells. The metabolite analyses revealed specific profiles that may be involved in the growth of neoplastic cells. All of these perturbations could thus be responsible for the loss of tumor suppressor status of MECs and promote the transition from in situ to invasive carcinoma.

Hormonal Therapy Resistance and Breast Cancer: Involvement of Adipocytes and Leptin.

Obesity, a recognized risk factor for breast cancer in postmenopausal women, is associated with higher mortality rates regardless of menopausal status, which could in part be explained by therapeutic escape. Indeed, adipose microenvironment has been described to influence the efficiency of chemo- and hormonal therapies. Residual cancer stem cells could also have a key role in this process. To understand the mechanisms involved in the reduced efficacy of hormonal therapy on breast cancer cells in the presence of adipose secretome, human adipose stem cells (hMAD cell line) differentiated into mature adipocytes were co-cultured with mammary breast cancer cells and treated with hormonal therapies (tamoxifen, fulvestrant). Proliferation and apoptosis were measured (fluorescence test, impedancemetry, cytometry) and the gene expression profile was evaluated. Cancer stem cells were isolated from mammospheres made from MCF-7. The impact of chemo- and hormonal therapies and leptin was evaluated in this population. hMAD-differentiated mature adipocytes and their secretions were able to increase mammary cancer cell proliferation and to suppress the antiproliferative effect of tamoxifen, confirming previous data and validating our model. Apoptosis and cell cycle did not seem to be involved in this process. The evaluation of gene expression profiles suggested that STAT3 could be a possible target. On the contrary, leptin did not seem to be involved. The study of isolated cancer stem cells revealed that their proliferation was stimulated in the presence of anticancer therapies (tamoxifen, fulvestrant, doxorubicine) and leptin. Our study confirmed the role of adipocytes and their secretome, but above all, the role of communication between adipose and cancer cells in interfering with the efficiency of hormonal therapy. Among the pathophysiological mechanisms involved, leptin does not seem to interfere with the estrogenic pathway but seems to promote the proliferation of cancer stem cells.

Bis(4-hydroxy-2H-chromen-2-one) Coumarin Induces Apoptosis in MCF-7 Human Breast Cancer Cells Through Aromatase Inhibition.

AIM: The present investigation aimed to examine the therapeutic potential of the new coumarin derivative bis(4-hydroxy-2H-chromen-2-one) coumarin (4HC) against breast cancer. MATERIALS AND METHODS: For this purpose, the effects of 4HC treatment on the proliferation of MCF-7 breast cancer cells and on MCF-10a non-cancerous cells were evaluated using a fluorescent assay. Cell cycle distribution and apoptosis were measured by image cytometry. The expression level of aromatase (CYP19A1) and apoptosis-related genes were determined by real-time PCR. RESULTS: MCF-7 mammary cancer cell proliferation was significantly decreased within 24 h after treatment with 4HC at 50 µM, while no effect was observed on the viability of MCF-10a non-cancerous mammary cells. 4HC also increased the percentage of the cells in the G2/M phase, inducing apoptosis. Real-time PCR revealed that 4HC induced MCF-7 mortality through an up-regulation of Bax and a down-regulation of Bcl-2, resulting in an increase in caspase-3 gene expression. The increased expression of apoptosis-related genes was accompanied by a decrease in CYP19A1 gene expression. CONCLUSION: 4HC selectively inhibits proliferation of MCF-7cells in vitro. Moreover, 4HC has inhibitory effects on aromatase gene expression and promoting effects on apoptosis, in MCF-7 cells.

Adipocyte/breast cancer cell crosstalk in obesity interferes with the anti-proliferative efficacy of tamoxifen.

BACKGROUND: Obesity is a well-known risk factor of breast cancer in post-menopausal women that also correlates with a diminished therapeutic response. The influence of adipocytes and their secretome, i.e. adipokines, on the efficacy of hormone therapy has yet to be elucidated. METHODS: We investigated, ex vivo, whether mature adipocytes, differentiated from adipose stem cells of normal-weight (MA20) or obese (MA30) women, and their secretions, were able to counteract the effects of tamoxifen (Tx) which is known to decrease neoplastic cell proliferation. RESULTS: In a tridimensional model and in a model of co-culture, the anti-proliferative effect of Tx on MCF-7 cancer cells was counteracted by MA30. These two models highlighted two different specific gene expression profiles for genes encoding cytokines or involved in angiogenesis based on the adipocyte microenvironment and the treatment. Thus it notably showed altered expression of genes such as TNFα that correlated with IL-6. In addition, leptin, IL-6 and TNFα, at concentrations reflecting plasma concentrations in obese patients, decreased the anti-proliferative efficacy of 4-hydroxytamoxifen (a major active metabolite of Tx). CONCLUSIONS: These findings bring insights on adipocytes and mammary cancer cell interactions in Tx therapy, particularly in overweight/obese people. Indeed, patient' adipokine status would give valuable information for developing individual strategies and avoid resistance to treatment.

Supernatants of Adipocytes From Obese Versus Normal Weight Women and Breast Cancer Cells: In Vitro Impact on Angiogenesis.

Breast cancer is correlated with a higher risk of metastasis in obese postmenopausal women. Adipokines, whose plasma concentrations are modulated in obese subjects and adipocytes surround mammary cells, suggesting that adipocyte secretome affect mammary tumorogenesis. We hypothesize that mature adipocyte secretions from obese women conditioned or not by breast neoplasic cells, increase changes on the angiogenesis stages. Supernatants of human mature adipocytes, differentiated from stem cells of either adipose tissue of normal weight (MA20) or obese (MA30) women or obtained from co-cultures between MA20 and MA30 and breast cancer cell line MCF-7, were collected. The impact of these supernatants was investigated on proliferation, migration, and tube formation by endothelial cells (HUVEC). MA20 and MA30 showed a preservation of their "metabolic memory" (increase of Leptin, ObR, VEGF, CYP19A1, and a decrease of Adiponectin expression in MA30 compared to MA20). Supernatants from obese-adipocytes increased HUVEC proliferation, migration, and sprouting like with supernatants obtained from co-cultures of MA/MCF-7 regardless the women's BMI. Additional analyses such as the use of neutralizing antibodies, analysis of supernatants (Milliplex®) and variations in gene expression (qRT-PCR), strongly suggest an implication of IL-6, or a synergistic action among adipokines, probably associated with that of VEGF or IL-6. As a conclusion, supernatants from co-cultures of MA30 and MCF-7 cells increase proliferation, migration, and sprouting of HUVEC cells. These results provide insights into the interaction between adipocytes and epithelial cancer cells, particularly in case of obesity. The identification of synergistic action of adipokines would therefore be a great interest in developing preventive strategies. J. Cell. Physiol. 232: 1808-1816, 2017. © 2016 Wiley Periodicals, Inc.

Effects of Spiro-bisheterocycles on Proliferation and Apoptosis in Human Breast Cancer Cell Lines.

Breast cancer is the leading cause of cancer-related death in women worldwide and a critical public health concern. Here we investigated the anticancer potential and effects of low-molecular-weight bridgehead oxygen and nitrogen-containing spiro-bisheterocycles on proliferation and apoptosis of the human breast cancer cell lines MCF-7 and MDA-MB-231. The compounds feature a hydantoin moiety attached to either diazole, isoxazole, diazepine, oxazepine or benzodiazepine via the privileged tetrahedral spiro-linkage. Treatment with compounds spiro [hydantoin-isoxazole] and spiro [hydantoin-oxazepine] resulted in a dose-dependent decrease of cell proliferation and induction of apoptosis in both breast cancer cell lines, whereas spiro [hydantoin-diazepine] was only active against MDA-MB 231. Quantitative reverse transcription polymerase chain reaction analysis showed up-regulation of murine double minute 2 (MDM2), strictly p53-dependent, and detected an increase in expression of pro-apoptotic caspase 3 and BCL2-associated X (BAX) genes in both breast cancer cell lines expressing wild-type and mutant p53. In summary, the results suggest that our compounds promote apoptosis of breast cancer cell lines via p53-dependent and -independent pathways.

Leptin, adipocytes and breast cancer: Focus on inflammation and anti-tumor immunity.

More than one million new cases of breast cancer are diagnosed worldwide each year and more than 400,000 deaths are caused by the disease. The origin of this pathology is multifactorial and involved genetic, hormonal, environmental and nutritional factors including obesity in postmenopausal women. The role played by the adipose tissue and their secretions, ie adipokines, is beginning to be recognized. Plasma adipokine levels, which are modulated during obesity, could have "remote" effects on mammary carcinogenesis. Breast cancer cells are surrounded and locally influenced by an adipocyte microenvironment, which is probably more extensive in obese people. Hence, leptin appears to be strongly involved in mammary carcinogenesis and may contribute to the local pro-inflammatory mechanisms, especially in obese patients, who have increased metastatic potential and greater risk of mortality. This review presents the multifaceted role of leptin in breast cancer development and the different molecular pathways involved such as inflammation, oxidative stress and antitumor immunity.

Leptin induces a proliferative response in breast cancer cells but not in normal breast cells.

Obesity is a risk factor for breast cancer in postmenopausal women. Leptin, a hormone excessively produced during obesity, is suggested to be involved in breast cancer. The aim of the study was to investigate procarcinogenic potential of leptin by evaluating influence of leptin on cell proliferation, cell cycle, apoptosis, and signaling on numerous breast cells lines, including 184B5 normal cells, MCF10A fibrocystic cells and MCF-7, MDA-MB-231, and T47D cancer cells. Expressions of leptin and Ob-R were analyzed using qRT-PCR and immunohistochemistry, proliferation using fluorimetric resazurin reduction test and xCELLigence system, apoptosis and cell cycle by flow cytometry, and effect of leptin on different signalling pathways using qRT-PCR and Western blot. Cells were exposed to increasing concentrations of leptin. All cell lines expressed mRNA and protein of leptin and Ob-R. Leptin stimulated proliferation of all cell lines except for 184B5 and MDA-MB-231 cells. Leptin inhibited apoptosis but didn't alter proportion of cells within cell cycle in MCF7 cells. Leptin induced overexpression of leptin, Ob-R, estrogen receptor, and aromatase mRNA in MCF-7 and T47D cells. Autoregulation induced by leptin, relationship with estrogen pathway, and proliferative and antiapoptic activity in breast cancer cells may explain that obesity-associated hyperleptinemia may be a breast cancer risk factor.

Assessing the dual activity of a chalcone-phthalocyanine conjugate: design, synthesis, and antivascular and photodynamic properties.

Photodynamic therapy (PDT) and vascular-disrupting agents (VDA) each have their advantages in the treatment of solid tumors, but also present drawbacks. In PDT, hypoxia at the center of the tumor limits conversion of molecular oxygen into singlet oxygen, while VDAs are deficient at affecting the rim of the tumor. A phthalocyanine-chalcone conjugate combining the VDA properties of chalcones with the PDT properties of phthalocyanines was designed to address these deficiencies. Its vascular targeting, photophysical, photochemical, photodynamic activities are reported herein.

Reciprocal interactions between breast tumor and its adipose microenvironment based on a 3D adipose equivalent model.

Breast cancer has become the most common cancer among women in industrialized countries. Obesity is well established as a risk factor, in particular owing to the attendant secretion of the entities called adipokines; there is growing evidence for a role of cells and factors present in the mammary tumor microenvironment such as fibroblasts, preadipocytes, adipocytes and their secretions. To study how the microenvironment influences breast cancer growth, we developed a novel tridimensional adipose model epithelialized with normal human keratinocytes or with breast cancer cell lines. These mimicked a breast tumor in contact with an adipose microenvironment and allowed monitoring of the interactions between the cells. Leptin and adiponectin, two major adipokines, and their respective receptors, ObRt and AdipoR1, were expressed in the model, but not the second adiponectin receptor, AdipoR2. The differentiation of preadipocytes into adipocytes was greater when they were in contact with the breast cancer cell lines. The contact of breast cancer cell lines with the microenvironment completely modified their transcriptional programs by increasing the expression of genes involved in cell proliferation (cyclinD1, MAPK), angiogenesis (MMP9, VEGF) and hormonal pathways (ESR1, IL6). This tridimensional adipose model provides new insights into the interactions between breast cancer cells and their adipose microenvironment, and provides a tool to develop new drugs for the treatment of both cancer and obesity.

Breast cancer and obesity: in vitro interferences between adipokines and proangiogenic features and/or antitumor therapies?

Obesity is now considered as a risk factor for breast cancer in postmenopausal women. Adipokine levels are modulated in obesity, and may play a role in carcinogenesis. Moreover, obesity increases risk of cancer mortality. Here, we hypothesized that this increase could be due to a modification in angiogenesis, capital event in the development of metastases, and/or in effectiveness of cancer treatments. To test these assumptions, following a same experimental design and simultaneously the effects of leptin and adiponectin on angiogenesis were investigated, and the impact of hyperleptinemia on anticancer drug effectiveness was measured in physiological and obesity situations. Focusing on angiogenesis, the proliferation of endothelial cells (HUVEC), which expressed leptin and adiponectin receptors, was stimulated by leptin and inhibited by adiponectin. Both adipokines globally reduced apoptosis and caspase activity. Leptin increased migration whereas adiponectin decreased migration, and leptin enhanced the area of the tubes formed by HUVEC cells while adiponectin inhibited their formation. MCF7 and MDA-MB-231 cells treated with leptin secreted more VEGF than untreated cells, whereas adiponectin treatment inhibited VEGF secretion. Finally, MCF7 cells pre-treated with leptin were more invasive than untreated cells. This effect was not reproduced in MDA-MB-231 cells. In the MCF7 breast cancer cell line, leptin could induce cell proliferation and reduced the efficacy of all breast cancer therapies (tamoxifen, 5-fluorouracil, taxol and vinblastin). These results suggest that, in obesity situation, leptin- in contrast to adiponectin - may promote tumor invasion and angiogenesis, leading to metastases 'apparition, and reduce treatment efficacy, which could explain the increased risk of cancer mortality in cases of overweight. The evidence suggests adipokines influence breast cancer issue and could play a significant role, especially in obese patients for which hyperleptinemia, hypoadiponectinemia and increased metastatic potential are described.

[Leptin: Involvement in the pathophysiology of breast cancer]. / Leptine : implication dans la physiopathologie du cancer du sein.

More than one million new cases of breast cancer are diagnosed each year worldwide and more than 400,000 deaths occur due to this pathology. Obesity is a risk factor for postmenopausal breast cancer and the place held by the adipose tissue and secretions (i.e. adipokines) begins to be recognized. Indeed, firstly, plasma adipokine levels, modulated in obesity situation, could have effects "remotely" on mammary carcinogenesis and, secondly, breast cancer cells are surrounded by adipocyte microenvironment, which is probably more important in the case of obesity, and may be locally influenced by it. In this context, leptin appears to be strongly involved in mammary carcinogenesis and may contribute to the angiogenesis process and local pro-inflammatory mechanisms, especially in obese patients for whom increased metastatic potential and risk of mortality are described.