These data confirmed that IL4 enhances short-term glucose uptake and possibly its rate of metabolism in mammary malignancy cells. cancer cells, it increased expression of the main glutamine transporter, ASCT2, and enhanced glutamine consumption in both MDA-MB-231 and Dovitinib lactate 4T1 cells. Pharmacologic inhibition of glutamine metabolism with compound 968 blocked IL4/IL4R-increased cell number in both cell lines. Our results demonstrate that IL4R mediates enhanced glucose and glutamine metabolism in 4T1 cancer cells, and that IL4-induced growth is usually supported by IL4/IL4R-enhanced glutamine metabolism in both human and murine mammary cancer cells. This highlights IL4R as Dovitinib lactate a possible target for effective breast cancer therapy. strong class=”kwd-title” Keywords: cytokine, proliferation, survival, glucose, metabolism 1. Introduction Second only to skin cancer, breast cancer remains the most commonly diagnosed cancer in women in the United States [1]. Cytokines and chemokines Dovitinib lactate in the tumor microenvironment promote breast cancer progression and metastasis [2]. Interleukin-4 (IL4) is usually a Th2 immune Dovitinib lactate cytokine that binds and activates the type 1 IL4R on lymphoid cells (composed of the IL4R and common gamma C chains) to promote proliferation and survival [3]. Normal epithelial tissues typically do not express IL4R, yet many epithelial cancers including breast cancer, upregulate a second type of IL4R, called the type II IL4R, which consists of the IL4R and IL13Ra1 chains [4]. Notably, interleukin-13 (IL13) can also activate the Type II IL4R. However, IL4 is the prototypical IL4R ligand, it binds with higher affinity [5], and is upregulated in the breast tumor microenvironment in patients [6]. Using two immune qualified murine tumor models, we have defined IL4R expression in mammary cancer cells as a strong promoter of metastatic tumor growth mediating enhanced proliferation and survival [7]. Increased glucose consumption and utilization in activated lymphocytes supports these same pro-growth phenotypes [8,9]. Specifically, IL4 induces T cell proliferation [10], and IL4/IL4R-induced glucose metabolism is necessary to support the enhanced survival of B cells [8,11]. However, there is no data regarding whether IL4/IL4R-induced glucose metabolism serves as a novel mechanism to support tumor growth. Normally, cells use glycolysis to metabolize glucose to pyruvate, which is usually fed into the tricarboxylic acid (TCA) cycle and used to generate ATP through oxidative phosphorylation. Highly proliferative cells, including activated lymphocytes and cancer cells, induce a comparatively high rate of aerobic glycolysis and metabolize the majority of glucose to lactate even when oxygen is present [12]. This phenomenon, termed the Warburg effect in cancer, is often accompanied by elevated glucose transporter (GLUT) expression to facilitate increased glucose uptake, as generation of ATP per glucose molecule from aerobic glycolysis is usually relatively inefficient. Enhanced aerobic glycolysis in tumors is usually often indicated by increased extracellular lactate production as it correlates proportionally with intracellular glycolytic activity [13]. The reprogramming of metabolism is now considered an emerging hallmark of cancer because of its critical role in supporting rapid biosynthesis during periods of stress and proliferation [14]. How cancer cells achieve such metabolic reprogramming is now an area of intense investigation. There are 14 GLUT family members expressed in humans, of which GLUT1 is the most extensively studied in cancer for mediating upregulated glucose uptake and metabolism. Elevated expression of GLUT1 has been shown in many epithelial cancer types including breast cancer [15C18]. Importantly, IL4 signaling through the type I IL4R in B lymphocytes leads to increased expression of GLUT1 and other genes SERPINE1 encoding glycolytic enzymes [19], and GLUT1 expression has been associated with IL4-increased glucose uptake [8]. In the setting of aerobic glycolysis, both activated lymphocytes and cancer cells often also upregulate glutamine uptake and metabolism to maintain the TCA cycle [9,20], and to provide purines and pyrimidines for DNA and RNA synthesis [21]. While colon and lung cancers depend on enhanced glutamine metabolism for survival and proliferation, little is known about glutamine metabolism in breast cancer cells [22,23]. Enhanced glutamine uptake may occur through increased ASC amino-acid transporter 2 (ASCT2) expression, the major cancer-related glutamine transporter [24,25]. Indeed, ASCT2 is expressed by a variety of breast cancer subtypes including human luminal A, luminal B, HER2 positive, and triple unfavorable [26]. We have previously exhibited that a traditionally immune signaling axis, IL4/IL4R,.