2-D08 is a synthetic flavonoid and cell-permeable small ubiquitin-like modifier (SUMO) inhibitor, which also inhibits the Axl target with an IC50 of 0.49nM[1]. Protein SUMOylation is a dynamic post-translational modification involved in various biological processes in cellular homeostasis and development. 2-D08 inhibits SUMOylation by preventing the transfer of SUMO from the UBC9-SUMO thioester to substrates[2]. 2-D08 is commonly used to investigate the role of SUMOylation in various biological pathways and diseases, such as acute myeloid leukemia and demyelinating disorders[3,4].
In vitro, incubation of C2C12 myoblasts with 2-D08 (50, 100μM) for 24h induced significant morphological changes and markedly inhibited cell viability, with the highest dose of 100µM reducing cell viability by up to 20%[5]. Treatment of human uterine leiomyosarcoma (Ut-LMS) SK-LMS-1 and SK-UT-1B cell lines with 2-D08 (10-100μM) for 7 days resulted in a dose-dependent decrease in cell survival fraction and inhibited the colony-forming ability of Ut-LMS cells[6]. Incubation of primary cultured oligodendrocyte precursor cells (OPCs) with 2-D08 (50μM) for 72h significantly increased the phosphorylation level of FYN tyrosine kinase and enhanced the expression of Kir4.1 and MBP proteins[4].
In vivo, administration of 2-D08 (1mg/kg; i.p.) daily, starting 48h after MOG35-55 immunization, significantly alleviated disease severity and promoted weight gain during the acute phase in experimental autoimmune encephalomyelitis (EAE) mice at 20 days post-immunization. 2-D08 (1mg/kg; i.v.) administered daily for 30 days, starting after symptom onset in EAE marmosets, promoted spinal cord myelin repair and improved motor coordination[4]. 2-D08 (10mg/kg; every three days) administered via intratumoral injection to C57BL/6J mice bearing RM-1 tumors for 2 weeks significantly suppressed tumor growth, reduced tumor mass, and increased tumor cell apoptosis[7].
References:
[1] FUJINO N, KUBO H, MACIEWICZ R A. Phenotypic screening identifies Axl kinase as a negative regulator of an alveolar epithelial cell phenotype[J]. Laboratory Investigation, 2017, 97(9): 1047-1062.
[2] KIM Y S, KEYSER S G L, SCHNEEKLOTH J S J. Synthesis of 2’, 3’, 4’-trihydroxyflavone (2-D08), an inhibitor of protein sumoylation[J]. Bioorganic & Medicinal Chemistry Letters, 2014, 24(4): 1094-1097.
[3] ZHOU P, CHEN X, LI M, et al. 2-D08 as a SUMOylation inhibitor induced ROS accumulation mediates apoptosis of acute myeloid leukemia cells possibly through the deSUMOylation of NOX2[J]. Biochemical and Biophysical Research Communications, 2019, 513(4): 1063-1069.
[4] LIU M, JIN S, FU X, et al. Activation of Kir4.1 Channels by 2-D08 Promotes Myelin Repair in Multiple Sclerosis[J]. Advanced Science, 2025: e02032.
[5] LIU H, LEE S M, JOUNG H. 2-D08 treatment regulates C2C12 myoblast proliferation and differentiation via the Erk1/2 and proteasome signaling pathways[J]. Journal of Muscle Research and Cell Motility, 2021, 42(2): 193-202.
[6] JOUNG H, LIU H. 2-D08 mediates notable anticancer effects through multiple cellular pathways in uterine leiomyosarcoma cells[J]. Oncology Reports, 2024, 52(1): 97.
[7] XIAO J, SUN F, WANG Y N, et al. UBC9 deficiency enhances immunostimulatory macrophage activation and subsequent antitumor T cell response in prostate cancer[J]. Journal of Clinical Investigation, 2023, 133(4): e158352.