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Macrophages are particularly abundant and play an important role throughout the tumor progression process, namely, tumor‐associated macrophages (TAM) in the tumor microenvironment. TAM can be polarized to disparate functional phenotypes, the M1 and M2 macrophages. M1‐like type macrophages are defined as pro‐inflammatory cells involved in killing cancer cells, while M2‐like type cells can specially promote tumor growth and metastasis, tissue remodeling and immunosuppression. In this study, we first found that integrin β3 was highly expressed on the surface of TAM, both in vivo and in vitro, that displayed the M2‐like characteristics. Under intervention of CYC or triptolide, the integrin β3 inhibitors, the M2 polarization of TAM could be inhibited. Moreover, in the cell model of M2 polarization, either blockade or knockout/knockdown of integrin β3 could also suppress macrophage M2 polarization, which suggested that the M2 polarization was dependent on integrin β3. Using knockdown of peroxisome proliferator‐activated receptor‐γ (PPARγ), an M2 regulator, we found that expression and activation of PPARγ participated in M2 polarization that was mediated by integrin β3. Finally, to verify the activity of integrin β3 inhibitors on TAM in vivo, 4T1 tumor‐bearing mice were treated with CYC or triptolide; in response, the M1/M2 ratio of TAM was up‐regulated, while the infiltration of total lymphocytes into tumor tissue was not altered. In general, our study found a connection between integrin β3 and macrophage polarization, which provides a strategy for facilitating M2 to M1 repolarization and reconstructing the tumor immune microenvironment.

With the increasing penetration of renewable energy, the uncertainty of its power output will pose severe challenges for the reactive voltage operation of the receiving power grid. In view of the situation, a mathematical model for reactive power regulation is established in this paper, and based on Model Predictive Control, we propose a multiple-timescale optimal reactive voltage control method to reduce the effects of wind and photovoltaic uncertainties on voltage control. The IEEE-57 node system with renewable energy integration is adopted to verify the proposed model, and the results are obtained via Whale optimization Algorithm based Simulated Annealing (WOASA), which proves that with the multiple time-scale control method, the operation safety can be effectively improved, which can unleash the potential of reactive power regulation at the receiving power grid.

Tumor-associated macrophages (TAMs) are the most widely infiltrating immune cells in the tumor microenvironment (TME). Clinically, the number of TAMs is closely correlated with poor outcomes in multiple cancers. The biological actions of TAMs are complex and diverse, including mediating angiogenesis, promoting tumor invasion and metastasis, and building an immunosuppressive microenvironment. Given these pivotal roles of TAMs in tumor development, TAM-based strategies are attractive and used in certain tumor therapies, including inhibition of angiogenic signalling, blockade of the immune checkpoint, and macrophage enhancement phagocytosis. Several attempts to develop TAM-targeted agents have been made to deplete TAMs or reprogram the behaviour of TAMs. Some have shown a favourable curative effect in monotherapy, combination with chemotherapy or immunotherapy in clinical trials. Additionally, a new macrophage-based cell therapeutic technology was recently developed by equipping macrophages with CAR molecules. It is expected to break through barriers to solid tumor treatment. Although TAM-related studies have yielded positive antitumor outcomes, further investigations are needed to better characterize TAMs, which will benefit further establishment of novel strategies for tumor therapy. Here, we concisely summarize the functions of TAMs in the TME and comprehensively introduce the latest TAM-based regimens in cancer treatment.

B7-H3 is an immune checkpoint molecule from the B7 superfamily. It has been widely studied in tumor immune evasion in certain types of cancer. In our preliminary study, we found that B7-H3 is specifically enriched in tumor-associated macrophages (TAMs) in triple-negative breast cancer (TNBC) patients and strongly correlated with poor clinical prognosis. However, the role of B7-H3 in breast cancer remains elusive. Our current study aims to explore the potential of B7-H3 as a novel target in TNBC therapy. Here, we demonstrated that B7-H3 enriched on TAMs is tightly correlated with TNBC clinical progression. B7-H3high TAMs exhibit great pro-metastatic and immunosuppressive functions by intriguing extracellular matrix (ECM) reconstruction and tumor angiogenesis, therefore helping tumor cell dissemination and dampening T-cell infiltration in tumor microenvironment (TME). Importantly, targeting blockade of B7-H3 by anti-B7-H3 antibody improves the tumor vasculature disorder, thereby enhancing chemotherapy and PD-1 therapy efficacy. In conclusion, our study establishes the correlation between B7-H3high TAMs and TNBC progression for the first time. By exploring the possibility of targeting B7-H3 expressed in both tumor cells and TAMs, we suggest that B7-H3 could be a promising target in clinical TNBC treatment.

Many studies have shown that chronic stress can cause neuronal damage and depression, but this exact mechanism still remains unknown. Neurons are vulnerable to lipid peroxidation-induced damage because the major part of neuronal cell membrane is polyunsaturated fatty acids that are substrate for reactive oxygen species. Since endogenous antioxidant defense systems normally eliminate production of reactive oxygen species, deficient antioxidant defense can cause oxidative stress-induced damage. In the present study, to understand the role of endogenous antioxidant defense in chronic stress-induced neuronal damage, we analyzed lipid peroxidation, total antioxidant capacity, and activities of catalase and glutathione peroxidase in frontal cortex, hippocampus and striatum of rats exposed to chronic unpredictable stress. We found that chronic unpredictable stress for four weeks in rats induced depressive-like behaviors such as anhedonia, despair and decreased exploration. Malondialdehyde, a lipid peroxidation product, is increased, but total antioxidant capacity, glutathione peroxidase activity and catalase activity are decreased in brain of rats exposed to chronic unpredictable stress. Our findings suggest that down regulation of endogenous antioxidant defense induces lipid peroxidation contributing a role to chronic stress and depression.

Tumor-associated macrophages are increasingly viewed as a target of great relevance in the tumor microenvironment, because of their important role in cancer progression and metastasis. However, the endogenous regulatory mechanisms underlying tumor-associated macrophage differentiation remain largely unknown. Here, we report that caspase-1 promotes tumor-associated macrophage differentiation by cleaving peroxisome proliferator-activated receptor gamma (PPARγ) at Asp64, thus generating a 41 kDa fragment. This truncated PPARγ translocates to mitochondria, where it directly interacts with medium-chain acyl-CoA dehydrogenase (MCAD). This binding event attenuates MCAD activity and inhibits fatty acid oxidation, thereby leading to the accumulation of lipid droplets and promoting tumor-associated macrophage differentiation. Furthermore, the administration of caspase-1 inhibitors or the infusion of bone marrow-derived macrophages genetically engineered to overexpress murine MCAD markedly suppresses tumor growth. Therefore, targeting the caspase-1/PPARγ/MCAD pathway might be a promising therapeutic approach to prevent tumor progression., Tumor associated macrophages (TAMs) promote cancer progression. Here, the author show that caspase-1 promotes TAMs differentiation by attenuating medium-chain acyl-CoA dehydrogenase activity and that inhibition of this axis results in suppression of tumour growth in a transgenic mouse model of breast cancer.

Post-translational regulation plays a critical role in the control of cell growth and proliferation. The phosphorylation of peroxisome proliferator-activated receptor γ (PPARγ) is the most important post-translational modification. The function of PPARγ phosphorylation has been studied extensively in the past. However, the relationship between phosphorylated PPARγ1 and tumors remains unclear. Here we investigated the role of PPARγ1 phosphorylation in human fibrosarcoma HT1080 cell line. Using the nonphosphorylation (Ser84 to alanine, S84A) and phosphorylation (Ser84 to aspartic acid, S84D) mutant of PPARγ1, the results suggested that phosphorylation attenuated PPARγ1 transcriptional activity. Meanwhile, we demonstrated that phosphorylated PPARγ1 promoted HT1080 cell proliferation and this effect was dependent on the regulation of cell cycle arrest. The mRNA levels of cyclin-dependent kinase inhibitor (CKI) p21(Waf1/Cip1) and p27(Kip1) descended in PPARγ1(S84D) stable HT1080 cell, whereas the expression of p18(INK4C) was not changed. Moreover, compared to the PPARγ1(S84A), PPARγ1(S84D) up-regulated the expression levels of cyclin D1 and cyclin A. Finally, PPARγ1 phosphorylation reduced sensitivity to agonist rosiglitazone and increased resistance to anticancer drug 5-fluorouracil (5-FU) in HT1080 cell. Our findings establish PPARγ1 phosphorylation as a critical event in human fibrosarcoma growth. These findings raise the possibility that chemical compounds that prevent the phosphorylation of PPARγ1 could act as anticancer drugs.

// Yuxin Shu 1, * , Yan Lu 1, * , Xiaojuan Pang 1 , Wei Zheng 1 , Yahong Huang 1 , Jiahong Li 1 , Jianguo Ji 3, 4 , Can Zhang 2 , Pingping Shen 1 1 State Key Laboratory of Pharmaceutical Biotechnology and Model Animal Research Center (MARC), Nanjing University, Nanjing 210023, China 2 Center of Drug Discovery, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, PR China 3 The State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing 100871, China 4 Institute of System Biomedicine, School of Basic Medical Sciences, Peking University, Beijing 100191, China * These authors contributed equally to this work Correspondence to: Pingping Shen, email: ppshen@nju.edu.cn Can Zhang, email: zhangcan@cpu.edu.cn Keywords: phosphorylation, PPARγ, PFKFB4, hepatocellular carcinoma, glycolysis Received: June 01, 2016 Accepted: October 14, 2016 Published: October 19, 2016 ABSTRACT Peroxisome proliferator-activating receptor γ (PPARγ), a transcription factor, is involved in many important biological processes, including cell terminal differentiation, survival and apoptosis. However, the role of PPARγ, which regulates tumour promoter and oncogene expression, is not well understood in hepatocellular carcinoma (HCC). In the present study, based on evidence from clinical samples that phosphorylation of PPARγ at Ser84 is up-regulated in human liver tumours, we confirmed that phosphorylation of PPARγ was also significantly increased in an HCC mouse model and was increased by Mitogen-activated protein kinase (MEK)/ Extracellular-signal-regulated kinases (ERK) kinase. Next, we performed an RNA microarray analysis, and our data indicated that dephosphorylation of PPARγ at Ser84 affects the expression of glycolysis-related genes and pro-proliferation genes, which supposedly promote proliferation of HCC cells. Using a chromatin immunoprecipitation (ChIP) assay, we demonstrated that the observed PPARγ-mediated induction of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 4 (PFKFB4) expression was directly modulated by the transcriptional activity of its promoter. Furthermore, using knockdown of PFKFB4, we elucidated that the stimulation of PPARγ phosphorylation on glycolysis and proliferation in HCC is dependent on PFKFB4. Together, these findings extend our understanding of how liver tumour cells reprogram their glycolytic pathways by post-translational modification of specific transcription factors and lay a foundation for the screening of new targets for the treatment of HCC.

High-fat diets (HFDs) have been found to influence central nervous system development and to cause cognitive impairments in human epidemiologic studies, as well as in animal investigations. These adverse effects on learning and memory induced by an HFD have been associated with an impaired hippocampus, including hippocampal oxidative damage. Previously, we had found that α-lipoic acid (α-LA) could ameliorate the oxidative stress in non-neural organs (liver, jejunum, and spleen) induced by a 10-week HFD (21.2% fat) food regimen in mice. In this study, we investigated whether a 10-week HFD (21.2% fat) induced oxidative stress in the hippocampus or impaired spatial learning in mice and whether LA ameliorated these effects. The HFD was found to induce oxidative stress (a decrease in catalase activity, glutathione peroxidase activity, and total antioxidative capacity and an increase in malondialdehyde levels) in the mouse hippocampus. In addition, we found that the HFD impaired spatial recognition memory of mice in the Y-maze paradigm. Furthermore, the hippocampal oxidative stress and impaired spatial recognition memory of the mice were reduced in HFD diets supplemented with 0.1% LA. These findings suggest that LA, as a strong antioxidant, may help prevent HFD-induced learning impairments by ameliorating associated oxidative stress in the hippocampus.