A common feature of cancer cells is their ability to rewire their metabolism to sustain the production of ATP and macromolecules needed for cell growth, division and survival. In particular, the importance of altered fatty acid metabolism in cancer has received renewed interest as, aside their principal role as structural components of the membrane matrix, they are important secondary messengers, and can also serve as fuel sources for energy production. In this review, we will examine the mechanisms through which cancer cells rewire their fatty acid metabolism with a focus on four main areas of research. (1) The role of de novo synthesis and exogenous uptake in the cellular pool of fatty acids. (2) The mechanisms through which molecular heterogeneity and oncogenic signal transduction pathways, such as PI3K–AKT–mTOR signalling, regulate fatty acid metabolism. (3) The role of fatty acids as essential mediators of cancer progression and metastasis, through remodelling of the tumour microenvironment. (4) Therapeutic strategies and considerations for successfully targeting fatty acid metabolism in cancer. Further research focusing on the complex interplay between oncogenic signalling and dysregulated fatty acid metabolism holds great promise to uncover novel metabolic vulnerabilities and improve the efficacy of targeted therapies.

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Reprogramming of fatty acid metabolism in cancer

Broad targeting of resistance to apoptosis in cancer.

Hypoxic Tumor Cell Modulates Its Microenvironment to Enhance Angiogenic and Metastatic Potential by Secretion of Proteins and Exosomes

The origin of cancer

Until recently, inflammatory chemokines were viewed mainly as indispensable “gate keepers” of immunity and inflammation. However, updated research indicates that cancer cells subvert the normal chemokine system and these molecules and their receptors become important constituents of the tumor microenvironment with very different ways to exert tumor-promoting roles. The CCR5 and the CCL5 ligand have been detected in some hematological malignancies, lymphomas, and a great number of solid tumors, but extensive studies on the role of the CCL5/CCR axis were performed only in a limited number of cancers. This review summarizes updated information on the role of CCL5 and its receptor CCR5 in cancer cell proliferation, metastasis, and the formation of an immunosuppressive microenvironment and highlights the development of newer therapeutic strategies aimed to inhibit the binding of CCL5 to CCR5, to inhibit CCL5 secretion, or to inhibit the interactions among tumor cells and the microenvironment leading to CCL5 secretion.

https://downloads.hindawi.com/journals/mi/2014/292376.pdf

The inflammatory chemokine CCL5 and cancer progression.

// Qi Wu 1, * , Juanjuan Li 1, * , Shan Zhu 1 , Juan Wu 2 , Chuang Chen 1 , Qian Liu 1 , Wen Wei 1 , Yimin Zhang 1 , Shengrong Sun 1 1 Department of Breast and Thyroid Surgery, Renmin Hospital of Wuhan University, Wuhan, Hubei, P. R. China 2 Department of Pathology, Renmin Hospital of Wuhan University, Wuhan, Hubei, P. R. China * These authors contributed equally to this work Correspondence to: Shengrong Sun, email: sun137@sina.com Yimin Zhang, email: dryiminzhang@163.com Keywords: breast cancer subtypes, distant metastases, SEER Received: November 01, 2016      Accepted: February 20, 2017      Published: March 02, 2017 ABSTRACT Background and Aims: This study aimed to access possible relationships between breast cancer subtypes and sites of distant metastasis in breast cancer. Results: A total of 243,896 patients, including 226,451 cases in control groups were identified. Bone metastasis was found in 8848 cases, compared with 1,000 brain metastasis cases, 3434 liver metastasis cases and 4167 lung metastasis cases. Patients with all subtypes were most prone to bone metastases, the incidence of bone metastasis in HR+/HER2+ subtype was up to 5.1 %. Further, HR−/HER2+ subtype patients had a higher probability of brain (OR = 1.978) metastasis compared to HR+/HER2− subtype patients. In addition, liver metastasis was more frequently observed in the HER2 positive subtypes compared with HER2 negative subtypes. Patients with TN primarily presented lung metastasis, but it made no difference in the probability of lung metastases of all subtypes. Materials and Methods: Using the 2010–2013 Surveillance, Epidemiology, and End Results Program(SEER) data, a retrospective, population-based cohort study to investigate tumor subtypes-specific differences in the sites of distant metastasis. Metastatic patterns information was provided for bone, brain, liver and lung. The breast cancer was classified into four subtypes: hormone receptor (HR) +/ human epidermal growth factor receptor 2 (HER2) −, HR+/HER2+, HR−/HER2+ and triple negative (TN). Conclusions: The pathological subtypes of breast cancer are clearly different in metastatic behavior with regard to the sites of distant metastasis, emphasizing that this knowledge may help to determine the appropriate strategy for follow-up and guide personalized medicine.

/pdf/breast-cancer-subtypes-predict-the-preferential-site-of-xvcb34vnd6.pdf

Breast cancer subtypes predict the preferential site of distant metastases: a SEER based study

Aim/hypothesis: Diabetes and breast cancer are both serious life-threatening diseases across the world. Some studies shows that diabetes is associated with many kinds of tumor, but links with breast cancer remain controversial. The aim of this study was to assess the association the available evidence. Subjects and methods: A meta-analysis was conducted including 16 studies published between 2000 and 2010 and summary relative risks(RRs) with 95% CIs were calculated using random-effects model. Results: The combined evidence supports that diabetes was associated with a statistically significant 23% increased risk of breast cancer, especially in postmenopausal women (RR=1.25 95%CI 1.20-1.29). The correlation between diabetes and breast cancer was the most obvious in Europe (RR=1.88,95%CI:1.56-2.25), followed by America (RR=1.16, 95%CI:1.12-1.20). In Asia the result was not significant (RR=1.01, 95%CI=0.84-1.21). Diabetes also increased mortality from breast cancer overall (RR=1.44, 95%CI:1.31-1.58). Conclusions/interpretation: This meta-analysis indicated that diabetes can be considered as a risk factor for breast cancer. In addition, menstruation status as well as geographical distribution can affect the relationship.

Association between diabetes mellitus and breast cancer risk: a meta-analysis of the literature.

Emerging evidence supports the pivotal roles of adipocytes in breast cancer progression. Tumour induced beige/brown adipose tissue differentiation contributes to the hypermetabolic state of the breast cancer. However, the mediators and mechanisms remain unclear. Survival probabilities were estimated using the Kaplan–Meier method based on immunohistochemistry results. Biochemical studies were performed to characterize the novel interrelation between breast cancer cells and adipocytes. We show that tumour-surrounding adipocytes exhibit an altered phenotype in terms of upregulated beige/brown characteristics and increased catabolism associated with an activated state characterized by the release of metabolites, including free fatty acids, pyruvate, lactate and ketone bodies. Likewise, tumour cells cocultivated with mature adipocytes exhibit metabolic adaptation and an aggressive phenotype in vitro and in vivo. Mechanistically, we show that tumour cells induce beige/brown differentiation and remodel metabolism in resident adipocytes by exosomes from the co-culture system that carry high levels of miRNA-144 and miRNA-126. miRNA-144 promotes beige/brown adipocyte characteristics by downregulating the MAP3K8/ERK1/2/PPARγ axis, and exosomal miRNA-126 remodels metabolism by disrupting IRS/Glut-4 signalling, activating the AMPK/autophagy pathway and stabilizing HIF1α expression in imminent adipocytes. In vivo inhibition of miRNA-144 or miRNA-126 decreases adipocyte–induced tumour growth. These results demonstrate that by inducing beige/brown differentiation and enhancing catabolism in recipient adipocytes, exosomal miRNA-144 and miRNA-126 from the tumour-adipocyte interaction reprogram systemic energy metabolism to facilitate tumour progression.

/pdf/exosomes-from-the-tumour-adipocyte-interplay-stimulate-beige-1fh3fwbq5l.pdf

Exosomes from the tumour-adipocyte interplay stimulate beige/brown differentiation and reprogram metabolism in stromal adipocytes to promote tumour progression

This study was undertaken to observe the effects and possible mechanism of CC chemokine ligand 5 (CCL5) on invasion, proliferation and percentage of CD44+/CD24- subpopulation of human breast cancer line MCF-7 and to investigate the correlation of expression levels of CCL5 and its receptors with the progression of breast cancer. We used real-time RT-PCR to detect the expression levels of CCL5 and its receptors CCR5, CCR1 and CCR3 in 36 breast cancer specimens of different TNM stage and their corresponding normal breast tissue. CCL5 expression and invasive ability of four human breast cancer cell lines MCF-7, SK-BR-3, T-47D and MDA-MB-231 were analyzed by real-time RT-PCR and cell invasion assay, respectively. Effects of recombinant human CCL5 (rhCCL5) on cell proliferation and percentage of the CD44+/CD24- subpopulation in MCF-7 cells were analyzed respectively by MTT assay and flow cytometry. We also used cell invasion assay to detect the invasive ability of both CD44+/CD24- and CD44+/CD24+ subpopulations of MCF-7 cells treated with rhCCL5 and/or CCR5 monoclonal antibody. Our results revealed that CCL5 and CCR5 expression were higher in breast cancer tissue than those in their corresponding normal tissue and breast cancer tissue with higher TNM stage contained more CCL5 mRNA. In addition, CCR5 expression and invasive ability of CD44+/CD24- subpopulation were higher than those of CD44+/CD24+ subpopulation of MCF-7 cells. Moreover, treatment of rhCCL5 increased the proportion of CD44+/CD24- cells and the proliferation of MCF-7 cells. Induction of rhCCL5 increased the cell invasive ability of both CD44+/CD24- and CD44+/CD24+ cells, which could be partially antagonized by CCR5 monoclonal antibody. Collectively, our data show that CCL5 increased the proportion of CD44+/CD24- subpopulation and induced invasion and proliferation of MCF-7 cells, and expression of CCL5 and CCR5 in breast cancer tissue was positively correlated with breast cancer progression.

/pdf/role-of-ccl5-in-invasion-proliferation-and-proportion-of-3vp6yg0bes.pdf

Role of CCL5 in invasion, proliferation and proportion of CD44+/CD24- phenotype of MCF-7 cells and correlation of CCL5 and CCR5 expression with breast cancer progression.

This study aimed to investigate the role of the cytoskeleton-associated protein vasodilator-stimulated phosphoprotein (VASP) on the migration and invasion of human breast cancer cells and its relationship to Rac1 which is a member of the Rho family and has been found to be implicated in tumorigenesis, invasion and metastasis. We detected the mRNA and protein expression levels of VASP and Rac1 of the non-invasive breast cancer cell line MCF-7 as well as the invasive cell line MDA-MB-231 by RT-PCR and Western blotting. GST pull-down assay was used to examine the activity of Rac1. Accordingly, the cell invasive migration ability was analyzed in a wound-healing assay (2D) and transwell assays (3D migration and invasion). We then used VASP-siRNA to inhibit the expression of VASP in breast cancer cells in order to study the relationship between the VASP expression level and the invasive migration ability of breast cancer cells. Rac1-siRNA was used to decrease the expression of Rac1, and observe its effect on the VASP expression level together with the migration and invasion ability of MCF-7 and MDA-MB-231 cells. Our results revealed that the invasive breast cancer cell line MDA-MB-231 showed a higher Rac1 activity and VASP expression level compared with the non-invasive MCF-7. Inhibition of Rac1 or VASP by siRNA, respectively, decreased the migration and invasion ability of breast cancer cells and the transfection of Rac1 siRNA-mediated reduction of VASP expression at mRNA and protein levels. Collectively, our data showed that the higher expression level of VASP contributed to a higher invasive migration capacity of human breast cancer cells which was controlled by the Rac1 pathway.

/pdf/positive-regulation-of-migration-and-invasion-by-vasodilator-kiuikkkqfq.pdf

Yimin Zhang

Papers

Breast cancer subtypes predict the preferential site of distant metastases: a SEER based study

Association between diabetes mellitus and breast cancer risk: a meta-analysis of the literature.

Exosomes from the tumour-adipocyte interplay stimulate beige/brown differentiation and reprogram metabolism in stromal adipocytes to promote tumour progression

Role of CCL5 in invasion, proliferation and proportion of CD44+/CD24- phenotype of MCF-7 cells and correlation of CCL5 and CCR5 expression with breast cancer progression.

Positive regulation of migration and invasion by vasodilator-stimulated phosphoprotein via Rac1 pathway in human breast cancer cells