Erythroblast Transformation-specific Transcription Research Articles

Erythroblast transformation-specific transcription factor fusions in prostate cancer.

224 Background: Common drivers in advanced prostate cancer (PC) involve fusions of the 3’ DNA binding domain-containing region of an Erythroblast Transformation Specific (ETS) transcription factor gene with a 5’ region of another gene, often one that is androgen-regulated. Previous work indicates that PCs harboring TMPRSS2:ERG fusions are more dependent on androgen signaling, and men with such tumors may, therefore, be more responsive to the effects of androgen deprivation therapy than men lacking this fusion. In this study, we examined the frequency of fusions involving ETS-family genes, including TMPRSS2:ERG, and determined how often such fusions would be missed if detection relied solely on DNA sequencing. Methods: To identify fusions and compare DNA-only versus DNA plus RNA sequencing, we utilized the Oncomap ExTra genomic profiling assay. This assay performs whole-exome, whole-transcriptome DNA and RNA sequencing of tumor and matched normal samples to identify somatic alterations in tumors. Single-nucleotide variants, indels, copy number alterations, alternative transcripts, and gene fusions are all detected. We specifically searched for fusions involving ETS transcription factor genes ERG and ETV1- 7. Results: A total of 512 PC patient samples assayed between April 2018 and July 2022 were included in the analysis; 226 ETS fusions were present in 223 (43.6%) patients; 3 patients carried two fusions. There were 196 ERG fusions including 185 (36.1%) patients having the familiar TMPRSS2: ERG fusion and 8 (1.6%) patients with a SLC45A3: ERG fusion, which is known to be associated with particularly poor prognosis. ETV1, 4, and 5 fusions were found in 29 (5.7%) patients and involved 12 different 5’ partner genes, the most common of which were SLC45A3 (6 fusions) and CANT1 (4 fusions). The two partner genes were on the same chromosome in 192 fusions, with 190 requiring a single deletion to create the fusion and 2 requiring a single inversion. For the 34 fusions involving genes on different chromosomes, a single translocation would be sufficient to produce the fusion gene in 23 cases; in 11 cases more than one structural rearrangement would be required. A total of 66 (29.6%) fusions were not detected in the DNA sequencing data, including 40 (21.6%) TMPRSS2: ERG fusions. In addition, 16 fusions were detected only in the DNA data, as RNA could not be sequenced, including 13 TMPRSS2: ERG fusions. Conclusions: In addition to TMPRSS2: ERG, the Oncomap ExTra assay identified several low frequency ETS fusions, all of which could be used to assist patients and physicians to select appropriate treatments. The identification of ETS fusions appears to be limited when using only DNA sequencing. Oncomap ExTra RNA analysis identified 66 additional fusions, representing almost 30% of those present, not identified by whole-exome DNA sequencing, suggesting RNA plus DNA assays detect fusions more reliably than DNA-only assays.

Prolonged fasting drives a program of metabolic inflammation in human adipose tissue

ObjectiveThe human adaptive fasting response enables survival during periods of caloric deprivation. A crucial component of the fasting response is the shift from glucose metabolism to utilization of lipids, underscoring the importance of adipose tissue as the central lipid-storing organ. The objective of this study was to investigate the response of adipose tissue to a prolonged fast in humans. MethodsWe performed RNA sequencing of subcutaneous adipose tissue samples longitudinally collected during a 10-day, 0-calorie fast in humans. We further investigated observed transcriptional signatures utilizing cultured human monocytes and Thp1 cells. We examined the cellularity of adipose tissue biopsies with transmission electron microscopy and tested for associated changes in relevant inflammatory mediators in the systemic circulation by ELISA assays of longitudinally collected blood samples. ResultsCoincident with the expected shift away from glucose utilization and lipid storage, we demonstrated downregulation of pathways related to glycolysis, oxidative phosphorylation, and lipogenesis. The canonical lipolysis pathway was also downregulated, whereas fasting drove alternative lysosomal paths to lipid digestion. Unexpectedly, the dominant induced pathways were associated with immunity and inflammation, although this only became evident at the 10-day time point. Among the most augmented transcripts were those associated with macrophage identity and function, such as members of the erythroblast transformation-specific (ETS) transcription factor family. Key components of the macrophage transcriptional signal in fasting adipose tissue were recapitulated with induced expression of two of the ETS transcription factors via cultured macrophages, SPIC and SPI1. The inflammatory signal was further reflected by an increase in systemic inflammatory mediators. ConclusionsCollectively, this study demonstrates an unexpected role of metabolic inflammation in the human adaptive fasting response.

ETS transcription factor ERG cooperates with histone demethylase KDM4A.

ERG (ETS-related gene) is a member of the ETS (erythroblast transformation-specific) family of transcription factors. Overexpression of the ERG transcription factor is observed in half of all prostate tumors and is an underlying cause of this disease. However, the mechanisms involved in the functions of ERG are still not fully understood. In the present study, we showed that ERG can directly bind to KDM4A (also known as JMJD2A), a histone demethylase that particularly demethylates lysine 9 on histone H3. ERG and KDM4A cooperated in upregulating the promoter of Yes-associated protein 1 (YAP1), a downstream effector in the Hippo signaling pathway and crucial growth regulator. Multiple ERG binding sites within the human YAP1 gene promoter were identified and their impact on transcription was determined through mutational analysis. Furthermore, we found that ERG expression reduced histone H3 lysine 9 trimethylation at the YAP1 gene promoter, consistent with its epigenetic regulation through the ERG interaction partner, KDM4A. Finally, downregulation of YAP1 phenocopied the growth-retarding effect of ERG or KDM4A depletion in human VCaP prostate cancer cells. Collectively, these results elucidated a novel mechanism - ERG promotes prostate tumorigenesis together with KDM4A through the upregulation of YAP1. A corollary is that KDM4A as well as YAP1 inhibitors may prove beneficial for the therapy of ERG-overexpressing prostate tumors.

Lack of ERG-antibody in Benign Mimickers of Prostate Cancer.

Prostate carcinoma (PC) is the second most diagnosed cancer in men worldwide. Prostate tissue in needle biopsy expresses a wide variety of architectural patterns some of which are difficult to interpret. Immunohistochemical markers, such as AMACR, p63 and 34βE12 that are currently used in diagnosing prostate cancer, are of great value, but often their interpretation is ambiguous. In 2005 Tomlins et al. identified an emerging marker, erythroblastosis E26 rearrangement gene (ERG), which is a member of the family of genes encoding erythroblast-transformation specific transcription factors (ETS) with frequent expression in PC. The aim of this study was to investigate the expression of ERG in benign mimickers of PC in needle biopsies and its diagnostic value alone and in combination with AMACK and 34βE12. Of the selected 46 biopsies, two were eventually diagnosed as PC Gleason score 6 as they were simultaneously ERG and AMACR-positive and 34βE12-negative. One case was considered atypical. The remaining 43 biopsies were diagnosed as benign cases: simple atrophy in 13 cases, partial atrophy in 11, adenosis in 9, basal cell hyperplasia in 3, post-atrophic hyperplasia in 3, clear cell hyperplasia in 2 and sclerotic adenosis in 2 cases. None of the 43 benign cores showed evidence of ERG expression. ERG could be preferably used in diagnosing prostate needle biopsies, lesions that are hard to interpret and controversial expression of AMACR/34βE12.

The role of ETS transcription factors in transcription and development of mouse preimplantation embryos

Embryonic transcription is a crucial process for the creation of new life. To clarify the mechanism of embryonic transcription, we investigated the expression and function of the erythroblast transformation specific (ETS) domain containing transcription factors (TFs) during preimplantation development in mice. The expression levels of several ETS TFs, i.e., etsrp71, elf3, and spic, increased after fertilization and remained at a high level until the blastocyst stage. To clarify the function of these TFs, we performed gene suppression using RNA interference, which revealed that they were involved in regulating development to the blastocyst stage. Furthermore, we found that suppression of ETS TFs affected the transcription of eIF- 1A and oct3/ 4 genes whose expression is regulated by TATA-less promoters in the embryos. These results suggest that ETS TFs function in the regulation of transcription with TATA-less promoters in preimplantation embryos, which is essential in preimplantation development.