Conversely, we show for the first time that KCNN2 is significantly underexpressed in ESFT when compared to ARMS. It seems reasonable to assume that this downregulation of KCNN2 in ESFT might be directly mediated by the chimeric GANT61 abmole transcription factor. On the other hand, although HIST1H4L was also found as a direct target of the EWSR1-FLI1 chimeric protein, our data showed that the expression of HIST1H4L was not significantly different between the ESFT and ARMS, thus suggesting that either EWSR1-FLI1 does not regulate HIST1H4L expression in vivo or that other regulatory mechanism in ARMS is regulating HIST1H4L to similar expression levels. In conclusion, using two different models of ETS-related tumors, we show that, despite of the conservation of the DNA binding domain of the ETS family of transcription factors, ETS proteins can modulate common target genes in different manners, as well as achieve specificity by controlling distinct genes. Mitochondria-localized glutamic acid-rich protein was first identified in the ovary as the ovary-specific acidic protein and, thereafter, it was identified in the cornea and retina. Since this protein is made up of abundant glutamic acids and has specific mitochondrion localization, it was given a universal name, MGARP. Our previous studies have demonstrated that MGARP is highly expressed in the inner segment of the photoreceptor, outer plexiform layer and ganglion cell layer of the retina, which are enriched with mitochondria. Additional studies have indicated that MGARP is involved in steroidogenesis through its ability to maintain mitochondrial abundance and morphology, and importantly, it is also highly expressed in the organs involved in steroidogenesis, such as the ovary, testis, adrenal gland and brain. MGARP can also be induced by HIF-1 and hypoxia, biasing mitochondrial transport in the anterograde direction and joining the mitochondrial dance. Our recent study reported temporal and tissue-specific expression patterns of MGARP during mouse development. The MGARP protein cannot be detected in the ovary or testis until 2–4 weeks after birth, likely depending on the availability of particular steroids. Furthermore, MGARP expression correlates with estrogen levels in the ovaries during the estrous cycle and it can be up-regulated by estrogen and down-regulated by a GnRH antagonist through a feedback regulatory mechanism. Steroid hormones play pivotal functions in the animal body throughout life. Their major physiological functions include the regulation of behavior, mood, reproduction, development, sex differences in brain function, aging, responses to the environmental stimuli and development of various diseases. The activity of steroid hormones is mediated by specific effectors such as steroid receptors that function as ligand-activated transcription factors. Estrogens can bind to the estrogen receptor and stimulate its translocation into the nucleus, where ERs bind to chromatin via specific ER-regulated elements to activate downstream gene transcription. It is also known that transactivators, including steroid receptors and particularly ER, depend on co-factors for full transcriptional regulation. Meanwhile, ER also serves as a co-factor for other transactivators. As a well established general transcriptional factor, Sp1 interacts with GC or GT boxes on the DNA backbone via its highly homologous zinc-finger domain. Its N-terminal glutamineand serine/threonine-rich domain can function as a transactivator, and its C-terminus has a synergistic activation function through its interaction with other transcription factors. Sp1 is implicated in a variety of biological processes.