The antisense promoter of human LINE-1 (L1) retroelements can direct transcription of adjacent unique genomic sequences generating chimeric RNAs, which can perturb transcription of neighbouring genes. As L1 elements constitute 17% of the human genome, chimeric transcription is potentially widespread, but the extent to which this occurs is largely unknown. Using a genome-wide screen we have isolated novel chimeric transcripts that are unique to breast cancer cell lines, primary tumours and colon cancer cells. Expression of the cancer-specific chimeric transcripts can be induced in non-malignant breast epithelial cells by the demethylating drug 5-azacytidine. These findings indicate that loss of L1 methylation in cancer cells is linked to the expression of L1-chimeric transcripts which may therefore constitute a useful set of markers of malignancy.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.ygeno.2009.08.013 | DOI Listing |
Genes Cells
January 2025
Department of Urology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan.
Tumor development often requires cellular adaptation to a unique, high metabolic state; however, the molecular mechanisms that drive such metabolic changes in TFE3-rearranged renal cell carcinoma (TFE3-RCC) remain poorly understood. TFE3-RCC, a rare subtype of RCC, is defined by the formation of chimeric proteins involving the transcription factor TFE3. In this study, we analyzed cell lines and genetically engineered mice, demonstrating that the expression of the chimeric protein PRCC-TFE3 induced a hypoxia-related signature by transcriptionally upregulating HIF1α and HIF2α.
View Article and Find Full Text PDFNat Cancer
January 2025
State Key Laboratory of Molecular Oncology, School of Life Sciences, Tsinghua-Peking Center for Life Sciences, Tsinghua University, Beijing, China.
Terminal exhaustion is a critical barrier to antitumor immunity. By integrating and analyzing single-cell RNA-sequencing and single-cell assay for transposase-accessible chromatin with sequencing data, we found that ETS variant 7 (ETV7) is indispensable for determining CD8 T cell fate in tumors. ETV7 introduction drives T cell differentiation from memory to terminal exhaustion, limiting antiviral and antitumor efficacy in male mice.
View Article and Find Full Text PDFJHEP Rep
January 2025
Department of Microbiology and Immunology, Hamamatsu University School of Medicine, Hamamatsu, Japan.
Background & Aims: Hepatic steatosis, characterized by lipid accumulation in hepatocytes, is a key diagnostic feature in patients with chronic hepatitis C virus (HCV) infection. This study aimed to clarify the involvement of phospholipid metabolic pathways in the pathogenesis of HCV-induced steatosis.
Methods: The expression and distribution of lipid species in the livers of human liver chimeric mice were analyzed using imaging mass spectrometry.
Biotechnol Bioeng
January 2025
Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland.
Human pluripotent stem cells (hPSCs) can be differentiated in vitro to an increasing number of mature cell types, presenting significant promise for addressing a wide range of diseases and studying human development. One approach to further enhance stem cell differentiation methods would be to coordinate multiple inducible gene or protein switches to operate simultaneously within the same cell, with minimal cross-interference, to precisely regulate a network of lineage-specifying transcription factors (TFs) to guide cell fate decisions. Therefore, in this study, we designed and tested various mammalian gene and protein switches responsive to clinically safe small-molecule inhibitors of viral proteases.
View Article and Find Full Text PDFCoronavirus disease 2019 (COVID-19) poses significant risks for solid organ transplant recipients, who have atypical but poorly characterized immune responses to infection. We aim to understand the host immunologic and microbial features of COVID-19 in transplant recipients by leveraging a prospective multicenter cohort of 86 transplant recipients age- and sex-matched with 172 non-transplant controls. We find that transplant recipients have higher nasal SARS-CoV-2 viral abundance and impaired viral clearance, and lower anti-spike IgG levels.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!