The deubiquitinating enzyme OTUD1 antagonizes BH3-mimetic inhibitor induced cell death through regulating the stability of the MCL1 protein

Abstract Receptor-interacting protein 1 (RIP1; RIPK1) is a key regulator of multiple signaling pathways that mediate inflammatory responses and cell death. TNF-TNFR1 triggered signaling complex formation, subsequent NF-κB and MAPK activation and induction of cell death involve RIPK1 ubiquitination at several lysine residues including Lys376 and Lys115. Here we show that mutating the ubiquitination site K376 of RIPK1 (K376R) in mice activates cell death resulting in embryonic lethality. In contrast to Ripk1K376R/K376R mice, Ripk1K115R/K115R mice reached adulthood and showed slightly higher responsiveness to TNF-induced death. Cell death observed in Ripk1K376R/K376R embryos relied on RIPK1 kinase activity as administration of RIPK1 inhibitor GNE684 to pregnant heterozygous mice effectively blocked cell death and prolonged survival. Embryonic lethality of Ripk1K376R/K376R mice was prevented by the loss of TNFR1, or by simultaneous deletion of caspase-8 and RIPK3. Interestingly, elimination of the wild-type allele from adult Ripk1K376R/cko mice was tolerated. However, adult Ripk1K376R/cko mice were exquisitely sensitive to TNF-induced hypothermia and associated lethality. Absence of the K376 ubiquitination site diminished K11-linked, K63-linked, and linear ubiquitination of RIPK1, and promoted the assembly of death-inducing cellular complexes, suggesting that multiple ubiquitin linkages contribute to the stability of the RIPK1 signaling complex that stimulates NF-κB and MAPK activation. In contrast, mutating K115 did not affect RIPK1 ubiquitination or TNF stimulated NF-κB and MAPK signaling. Overall, our data indicate that selective impairment of RIPK1 ubiquitination can lower the threshold for RIPK1 activation by TNF resulting in cell death and embryonic lethality.

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Sustained ER stress promotes hyperglycemia by increasing glucagon action through the deubiquitinating enzyme USP14

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1907288116 ◽

2019 ◽

Vol 116 (43) ◽

pp. 21732-21738 ◽

Cited By ~ 4

Author(s):

Bin Liu ◽

Zhijian Zhang ◽

Yanyun Hu ◽

Yan Lu ◽

Duanzhuo Li ◽

...

Keyword(s):

Er Stress ◽

Metabolic Diseases ◽

Low Grade ◽

Deubiquitinating Enzyme ◽

Obese Mice ◽

Hepatic Gluconeogenesis ◽

Regulatory Pathways ◽

Underlying Mechanisms ◽

The Stability ◽

Glucose Output

Endoplasmic reticulum (ER) stress plays an important role in metabolic diseases like obesity and type 2 diabetes mellitus (T2DM), although the underlying mechanisms and regulatory pathways remain to be elucidated. Here, we induced chronic low-grade ER stress in lean mice to levels similar to those in high-fat diet (HFD)–fed obese mice and found that it promoted hyperglycemia due to enhanced hepatic gluconeogenesis. Mechanistically, sustained ER stress up-regulated the deubiquitinating enzyme ubiquitin-specific peptidase 14 (USP14), which increased the stability and levels of 3′,5′-cyclic monophosphate–responsive element binding (CREB) protein (CBP) to enhance glucagon action and hepatic gluconeogenesis. Exogenous overexpression of USP14 in the liver significantly increased hepatic glucose output. Consistent with this, liver-specific knockdown of USP14 abrogated the effects of ER stress on glucose metabolism, and also improved hyperglycemia and glucose intolerance in obese mice. In conclusion, our findings show a mechanism underlying ER stress-induced disruption of glucose homeostasis, and present USP14 as a potential therapeutic target against T2DM.

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Control of AIF-mediated cell death by antagonistic functions of CHIP ubiquitin E3 ligase and USP2 deubiquitinating enzyme

Cell Death and Differentiation ◽

10.1038/cdd.2011.3 ◽

2011 ◽

Vol 18 (8) ◽

pp. 1326-1336 ◽

Cited By ~ 29

Author(s):

K H Oh ◽

S W Yang ◽

J M Park ◽

J H Seol ◽

S Iemura ◽

...

Keyword(s):

Cell Death ◽

E3 Ligase ◽

Deubiquitinating Enzyme ◽

Ubiquitin E3 Ligase

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Gossypol, a BH3 mimetic, induces apoptosis in chronic lymphocytic leukemia cells

Blood ◽

10.1182/blood-2007-12-126946 ◽

2008 ◽

Vol 112 (5) ◽

pp. 1971-1980 ◽

Cited By ~ 89

Author(s):

Kumudha Balakrishnan ◽

William G. Wierda ◽

Michael J. Keating ◽

Varsha Gandhi

Keyword(s):

Cell Death ◽

Chronic Lymphocytic Leukemia ◽

Outer Membrane ◽

Lymphocytic Leukemia ◽

Mitochondrial Outer Membrane ◽

Dependent Manner ◽

Antiapoptotic Proteins ◽

Downstream Effects ◽

Mitochondrial Membrane Permeabilization ◽

Bh3 Mimetic

Abstract Gossypol, a cottonseed extract derivative, acts as a BH3-mimetic, binding to the BH3 pocket of antiapoptotic proteins and displacing pro-death partners to induce apoptosis. However, knowledge on the molecular underpinnings of its downstream effects is limited. Since chronic lymphocytic leukemia (CLL) cells express high levels of antiapoptotic proteins that act as a survival mechanism for these replicationally quiescent lymphocytes, we investigated whether gossypol induces apoptosis in these cells and what mechanism underlies gossypol-mediated cytotoxicity. Gossypol induced cell death in a concentration- and time-dependent manner; 24-hour incubation with 30 μM gossypol resulted in 50% cell death (median; range, 10%-80%; n = 47) that was not abrogated by pan-specific caspase inhibitor. Starting at 4 hours, the mitochondrial outer membrane was significantly permeabilized (median, 77%; range, 54%-93%; n = 15). Mitochondrial outer membrane permeabiliztaion (MOMP) was concurrent with increased production of reactive oxygen species (ROS); however, antioxidants did not abrogate gossypol-induced cell death. Mitochondrial membrane permeabilization was also associated with loss of intracellular adenosine triphosphate (ATP), activation of BAX, and release of cytochrome c and apoptosis-inducing factor (AIF), which was translocated to the nucleus. Blocking AIF translocation resulted in a decreased apoptosis, suggesting that AIF contributes to gossypol-mediated cytotoxicity in CLL lymphocytes.

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The BH3 mimetic HA14-1 enhances 5-fluorouracil-induced autophagy and type II cell death in oesophageal cancer cells

British Journal of Cancer ◽

10.1038/bjc.2011.604 ◽

2012 ◽

Vol 106 (4) ◽

pp. 711-718 ◽

Cited By ~ 9

Author(s):

M J Nyhan ◽

T R O'Donovan ◽

B Elzinga ◽

L C Crowley ◽

G C O'Sullivan ◽

...

Keyword(s):

Cell Death ◽

Cancer Cells ◽

Oesophageal Cancer ◽

Type Ii ◽

Type Ii Cell ◽

Bh3 Mimetic

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Fatty acid synthase (FASN) regulates the mitochondrial priming of cancer cells

Cell Death and Disease ◽

10.1038/s41419-021-04262-x ◽

2021 ◽

Vol 12 (11) ◽

Author(s):

Barbara Schroeder ◽

Travis Vander Steen ◽

Ingrid Espinoza ◽

Chandra M. Kurapaty Venkatapoorna ◽

Zeng Hu ◽

...

Keyword(s):

Breast Cancer ◽

Cell Death ◽

Fatty Acid ◽

Cancer Cells ◽

Cancer Cell ◽

Breast Cancer Cells ◽

Fatty Acid Synthase ◽

Xenograft Model ◽

Fine Tuning ◽

Bh3 Mimetic

AbstractInhibitors of the lipogenic enzyme fatty acid synthase (FASN) have attracted much attention in the last decade as potential targeted cancer therapies. However, little is known about the molecular determinants of cancer cell sensitivity to FASN inhibitors (FASNis), which is a major roadblock to their therapeutic application. Here, we find that pharmacological starvation of endogenously produced FAs is a previously unrecognized metabolic stress that heightens mitochondrial apoptotic priming and favors cell death induction by BH3 mimetic inhibitors. Evaluation of the death decision circuits controlled by the BCL-2 family of proteins revealed that FASN inhibition is accompanied by the upregulation of the pro-death BH3-only proteins BIM, PUMA, and NOXA. Cell death triggered by FASN inhibition, which causally involves a palmitate/NADPH-related redox imbalance, is markedly diminished by concurrent loss of BIM or PUMA, suggesting that FASN activity controls cancer cell survival by fine-tuning the BH3 only proteins-dependent mitochondrial threshold for apoptosis. FASN inhibition results in a heightened mitochondrial apoptosis priming, shifting cells toward a primed-for-death state “addicted” to the anti-apoptotic protein BCL-2. Accordingly, co-administration of a FASNi synergistically augments the apoptosis-inducing activity of the dual BCL-XL/BCL-2 inhibitor ABT-263 (navitoclax) and the BCL-2 specific BH3-mimetic ABT-199 (venetoclax). FASN inhibition, however, fails to sensitize breast cancer cells to MCL-1- and BCL-XL-selective inhibitors such as S63845 and A1331852. A human breast cancer xenograft model evidenced that oral administration of the only clinically available FASNi drastically sensitizes FASN-addicted breast tumors to ineffective single-agents navitoclax and venetoclax in vivo. In summary, a novel FASN-driven facet of the mitochondrial priming mechanistically links the redox-buffering mechanism of FASN activity to the intrinsic apoptotic threshold in breast cancer cells. Combining next-generation FASNis with BCL-2-specific BH3 mimetics that directly activate the apoptotic machinery might generate more potent and longer-lasting antitumor responses in a clinical setting.

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Enhanced Biomass and Astaxanthin Production of Haematococcus pluvialis by a Cell Transformation Strategy with Optimized Initial Biomass Density

Marine Drugs ◽

10.3390/md18070341 ◽

2020 ◽

Vol 18 (7) ◽

pp. 341

Author(s):

Feng Li ◽

Minggang Cai ◽

Mingwei Lin ◽

Xianghu Huang ◽

Jun Wang ◽

...

Keyword(s):

Cell Death ◽

Cell Transformation ◽

Haematococcus Pluvialis ◽

Cost Effective ◽

Control Group ◽

Biomass Density ◽

Cost Effective Method ◽

Astaxanthin Production ◽

The Stability ◽

Transformation Strategy

Astaxanthin from H. pluvialis is an antioxidant and presents a promising application in medicine for human health. The two-stage strategy has been widely adopted to produce astaxanthin by the Haematococcus industry and research community. However, cell death and low astaxanthin productivity have seriously affected the stability of astaxanthin production. This study aims to test the effect of cell transformation strategies on the production of astaxanthin from H. pluvialis and determine the optimal initial biomass density (IBD) in the red stage. The experimental design is divided into two parts, one is the vegetative growth experiment and the other is the stress experiment. The results indicated that: (1) the cell transformation strategy of H. pluvialis can effectively reduce cell death occurred in the red stage and significantly increase the biomass and astaxanthin production. (2) Compared with the control group, the cell mortality rate of the red stage in the treatment group was reduced by up to 81.6%, and the biomass and astaxanthin production was increased by 1.63 times and 2.1 times, respectively. (3) The optimal IBD was determined to be 0.5, and the highest astaxanthin content can reach 38.02 ± 2.40 mg·g−1. Thus, this work sought to give useful information that will lead to an improved understanding of the cost-effective method of cultivation of H. pluvialis for natural astaxanthin. This will be profitable for algal and medicine industry players.

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The deubiquitinating enzyme USP20 regulates the stability of the MCL1 protein

Biochemical and Biophysical Research Communications ◽

10.1016/j.bbrc.2022.01.019 ◽

2022 ◽

Author(s):

Jinan Feng ◽

Pengyang Liu ◽

Xiaonan Li ◽

Dian Zhang ◽

Hanbin Lin ◽

...

Keyword(s):

Deubiquitinating Enzyme ◽

The Stability

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Endogenous Bcl-xL is essential for Myc-driven lymphomagenesis in mice

Blood ◽

10.1182/blood-2011-07-367672 ◽

2011 ◽

Vol 118 (24) ◽

pp. 6380-6386 ◽

Cited By ~ 33

Author(s):

Priscilla N. Kelly ◽

Stephanie Grabow ◽

Alex R. D. Delbridge ◽

Andreas Strasser ◽

Jerry M. Adams

Keyword(s):

Cell Death ◽

Transgenic Mice ◽

Family Members ◽

Lymphoid Cells ◽

Close Relative ◽

B Lymphoma ◽

Normal Expression ◽

B Lymphoid ◽

Bh3 Mimetic ◽

Striking Contrast

Abstract Impaired apoptosis is a cancer hallmark, and some types of lymphomas and other cancers harbor mutations that directly affect key cell death regulators, such as Bcl-2 family members. However, because the majority of tumors seem to lack such mutations, we are examining the hypothesis that tumorigenesis can be sustained at least initially by the normal expression of specific endogenous pro-survival Bcl-2 family members. We previously demonstrated that the lymphomagenesis in Εμ-myc transgenic mice, which constitutively overexpress the c-Myc oncoprotein in B-lymphoid cells and develop pre-B and B-cell lymphomas, does not require endogenous Bcl-2. In striking contrast, we report here that loss in these mice of its close relative Bcl-xL attenuated the pre-neoplastic expansion of pro-B and pre-B cells otherwise driven by c-Myc overexpression, sensitized these cells to apoptosis and ablated lymphoma formation. Remarkably, even loss of a single bcl-x allele delayed the lymphomagenesis. These findings identify Bcl-xL as a prerequisite for the emergence of c-Myc–driven pre-B/B lymphoma and suggest that BH3 mimetic drugs may provide a prophylactic strategy for c-Myc–driven tumors.

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