All-trans-retinoic acid (RA) treatment induces remissions in acute promyelocytic leukemia (APL) cases expressing the t(15;17) product, promyelocytic leukemia (PML)/RA receptor alpha (RARalpha). Microarray analyses previously revealed induction of UBE1L (ubiquitin-activating enzyme E1-like) after RA treatment of NB4 APL cells. We report here that this occurs within 3 h in RA-sensitive but not RA-resistant APL cells, implicating UBE1L as a direct retinoid target. A 1.3-kb fragment of the UBE1L promoter was capable of mediating transcriptional response to RA in a retinoid receptor-selective manner. PML/RARalpha, a repressor of RA target genes, abolished this UBE1L promoter activity. A hallmark of retinoid response in APL is the proteasome-dependent PML/RARalpha degradation. UBE1L transfection triggered PML/RARalpha degradation, but transfection of a truncated UBE1L or E1 did not cause this degradation. A tight link was shown between UBE1L induction and PML/RARalpha degradation. Notably, retroviral expression of UBE1L rapidly induced apoptosis in NB4 APL cells, but not in cells lacking PML/RARalpha expression. UBE1L has been implicated directly in retinoid effects in APL and may be targeted for repression by PML/RARalpha. UBE1L is proposed as a direct pharmacological target that overcomes oncogenic effects of PML/RARalpha by triggering its degradation and signaling apoptosis in APL cells.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC122605 | PMC |
http://dx.doi.org/10.1073/pnas.052011299 | DOI Listing |
PLoS One
December 2024
Department of Hematology, the Second Xiangya Hospital, Central South University, Changsha, Hunan, China.
Aims: Acute promyelocytic leukemia (APL) progresses quickly and often leads to early hemorrhagic death. Treatment with all-trans retinoic acid (ATRA) promotes differentiation of APL cells and clinical remission, making APL a potentially curable malignancy. Understanding how ATRA works may lead to new treatments for other types of leukemia.
View Article and Find Full Text PDFCommun Biol
October 2024
Department of Physics and Astronomy "Ettore Majorana", University of Catania, Catania, Italy.
To understand how oncogenes affect genome organization, it is essential to visualize fundamental processes such as DNA replication and transcription at high resolution in intact cells. At the same time, it is important to determine the progression of the cell along the cell cycle, as cell cycle regulation is crucial for the control of cell proliferation and oncogenesis. Here, we present a super-resolution imaging-based method to analyze single cell nuclei sorted according to specific phases of the cell cycle.
View Article and Find Full Text PDFEur J Med Chem
November 2024
School of Pharmaceutical Sciences, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Xiamen, 361102, Fujian, China. Electronic address:
Acute promyelocytic leukemia (APL), a distinctive subtype of acute myeloid leukemia (AML), is characterized by the t(15; 17) translocation forming the PML-RARα fusion protein. Recent studies have revealed a crucial role of retinoid X receptor α (RXRα) in PML-RARα's tumorigenesis. This necessitates the development of dual RARα and RXRα targeting compounds for treating APL.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
August 2024
Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
In acute promyelocytic leukemia (APL), the promyelocytic leukemia-retinoic acid receptor alpha (PML/RARα) fusion protein destroys PML nuclear bodies (NBs), leading to the formation of microspeckles. However, our understanding, largely learned from morphological observations, lacks insight into the mechanisms behind PML/RARα-mediated microspeckle formation and its role in APL leukemogenesis. This study presents evidence uncovering liquid-liquid phase separation (LLPS) as a key mechanism in the formation of PML/RARα-mediated microspeckles.
View Article and Find Full Text PDFCancer Gene Ther
October 2024
Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine and School of Life Sciences and Biotechnology, Shanghai, China.
Arsenic trioxide (ATO) has exhibited remarkable efficacy in treating acute promyelocytic leukemia (APL), primarily through promoting the degradation of the PML-RARα fusion protein. However, ATO alone fails to confer any survival benefit to non-APL acute myeloid leukemia (AML) patients and exhibits limited efficacy when used in combination with other agents. Here, we explored the general toxicity mechanisms of ATO in APL and potential drugs that could be combined with ATO to exhibit synergistic lethal effects on other AML.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!