@article{EffenbergerBommertKunzetal.2017,
  author    = {Effenberger, Madlen and Bommert, Kathryn S. and Kunz, Viktoria and Kruk, Jessica and Leich, Ellen and Rudelius, Martina and Bargou, Ralf and Bommert, Kurt},
  title     = {Glutaminase inhibition in multiple myeloma induces apoptosis via MYC degradation},
  series = {Oncotarget},
  volume    = {8},
  journal   = {Oncotarget},
  number    = {49},
  doi       = {10.18632/oncotarget.20691},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-170168},
  pages     = {85858-85867},
  year      = {2017},
  abstract  = {Multiple Myeloma (MM) is an incurable hematological malignancy affecting millions of people worldwide. As in all tumor cells both glucose and more recently glutamine have been identified as important for MM cellular metabolism, however there is some dispute as to the role of glutamine in MM cell survival. Here we show that the small molecule inhibitor compound 968 effectively inhibits glutaminase and that this inhibition induces apoptosis in both human multiple myeloma cell lines (HMCLs) and primary patient material. The HMCL U266 which does not express MYC was insensitive to both glutamine removal and compound 968, but ectopic expression of MYC imparted sensitivity. Finally, we show that glutamine depletion is reflected by rapid loss of MYC protein which is independent of MYC transcription and post translational modifications. However, MYC loss is dependent on proteasomal activity, and this loss was paralleled by an equally rapid induction of apoptosis. These findings are in contrast to those of glucose depletion which largely affected rates of proliferation in HMCLs, but had no effects on either MYC expression or viability. Therefore, inhibition of glutaminolysis is effective at inducing apoptosis and thus serves as a possible therapeutic target in MM.},
  language  = {en}
}
@article{KunzBommertKruketal.2020,
  author    = {Kunz, Viktoria and Bommert, Kathryn S. and Kruk, Jessica and Schwinning, Daniel and Chatterjee, Manik and St{\"u}hmer, Thorsten and Bargou, Ralf and Bommert, Kurt},
  title     = {Targeting of the E3 ubiquitin-protein ligase HUWE1 impairs DNA repair capacity and tumor growth in preclinical multiple myeloma models},
  series = {Scientific Reports},
  volume    = {10},
  journal   = {Scientific Reports},
  doi       = {10.1038/s41598-020-75499-3},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-230632},
  year      = {2020},
  abstract  = {Experimental evidence suggests that ubiquitin-protein ligases regulate a number of cellular processes involved in tumorigenesis. We analysed the role of the E3 ubiquitin-protein ligase HUWE1 for pathobiology of multiple myeloma (MM), a still incurable blood cancer. mRNA expression analysis indicates an increase in HUWE1 expression levels correlated with advanced stages of myeloma. Pharmacologic as well as RNAi-mediated HUWE1 inhibition caused anti-proliferative effects in MM cell lines in vitro and in an MM1.S xenotransplantation mouse model. Cell cycle analysis upon HUWE1 inhibition revealed decreased S phase cell fractions. Analyses of potential HUWE1-dependent molecular functions did not show involvement in MYC-dependent gene regulation. However, HUWE1 depleted MM cells displayed increased DNA tail length by comet assay, as well as changes in the levels of DNA damage response mediators such as pBRCA1, DNA-polymerase beta, gamma H2AX and Mcl-1. Our finding that HUWE1 might thus be involved in endogenous DNA repair is further supported by strongly enhanced apoptotic effects of the DNA-damaging agent melphalan in HUWE1 depleted cells in vitro and in vivo. These data suggest that HUWE1 might contribute to tumour growth by endogenous repair of DNA, and could therefore potentially be exploitable in future treatment developments.},
  language  = {en}
}