Structure-Guided Design and In-Cell Target Profiling of a Cell-Active Target Engagement Probe for PARP Inhibitors

Here, we selectively target pancreatic ductal adenocarcinoma (PDAC) cells harboring a hemizygous gene essential for cell growth. MYB binding protein 1A (MYBBP1A), encoding a chromatin-bound protein, is hemizygous in most of the PDAC due to a chromosome 17p deletion that also spans TP53. We find that hemizygous MYBBP1A loss in isogenic PDAC cells promotes tumorigenesis but, paradoxically, homozygous MYBBP1A loss is associated with impaired cell growth and decreased tumorigenesis. Poly–adenosine 5′-diphosphate–ribose polymerase 1 (PARP1) interacts with MYBBP1A and displaces it from chromatin. Small molecules, such as olaparib, that trap PARP1 to chromatin are able to evict the minimal pool of chromatin-bound MYBBP1A protein in MYBBP1A hemizygous cells and impair cell growth, greater than its impact on wild-type cells. Our findings reveal how a cell essential gene with one allele lost in cancer cells can be preferentially susceptible to a specific molecular therapy, when compared to wild-type cells.

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Faculty Opinions recommendation of Demonstrating In-Cell Target Engagement Using a Pirin Protein Degradation Probe (CCT367766).

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.732298936.793541222 ◽

2018 ◽

Author(s):

John Lowe

Keyword(s):

Protein Degradation ◽

Target Engagement ◽

Cell Target

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Olaparib Combined with an ATR or Chk1 Inhibitor as a Treatment Strategy for Acquired Olaparib-Resistant BRCA1 Mutant Ovarian Cells

Diagnostics ◽

10.3390/diagnostics10020121 ◽

2020 ◽

Vol 10 (2) ◽

pp. 121 ◽

Cited By ~ 8

Author(s):

Brian T. Burgess ◽

Abigail M. Anderson ◽

J. Robert McCorkle ◽

Jianrong Wu ◽

Frederick R. Ueland ◽

...

Keyword(s):

Cell Cycle ◽

Dna Repair ◽

Drug Sensitivity ◽

Parp Inhibitors ◽

Clinical Development ◽

Cell Models ◽

Ovarian Cells ◽

A Cell ◽

Increased Sensitivity ◽

Chk1 Inhibitor

Objective: Despite the promise of PARP inhibitors (PARPi) for treating BRCA1/2 mutated ovarian cancer (OC), drug resistance invariably develops. We hypothesized rationale drug combinations, targeting key molecules in DNA repair pathways and the cell cycle may be synergistic and overcome acquired PARPi resistance. Methods: Drug sensitivity to PARPi alone and in combination with inhibitors of key DNA repair and cell cycle proteins, including ATR (VE-821), Chk1 (MK-8776), Wee1 (MK-1775), RAD51 (RI-1) was assessed in PARPi-sensitive (UWB1) and -resistant (UWB1-R) gBRCA1 mutant OC cell lines using a cell proliferation assay. The Bliss synergy model was used to estimate the two-drug combination effect and pharmacologic synergy (Bliss score ≥ 0) or antagonistic (Bliss score ≥ 0) response of the PARPi in combination with the inhibitors. Results: IC50 for olaparib alone was 1.6 ± 0.9 µM compared to 3.4 ± 0.6 µM (p = 0.05) for UWB1 and UWB1-R cells, respectively. UWB1-R demonstrated increased sensitivity to ATRi (p = 0.04) compared to UWB1. Olaparib (0.3–1.25 µM) and ATRi (0.8–2.5 µM) were synergistic with Bliss scores of 17.2 ± 0.2, 11.9 ± 0.6 for UWB1 and UWB1-R cells, respectively. Olaparib (0.3–1.25 µM) and Chk1i(0.05–1.25 µM) were synergistic with Bliss scores of 8.3 ± 1.6, 5.7 ± 2.9 for UWB1 and UWB1-R cells, respectively. Conclusions: Combining an ATRi or Chk1i with olaparib is synergistic in both PARPi-sensitive and -resistant BRCA1 mutated OC cell models, and are rationale combinations for further clinical development.

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Broad-Spectrum Anticancer Activity and Pharmacokinetic Properties of a Prenyloxy-Substituted Indeno[1,2-b]indole Derivative, Discovered as CK2 Inhibitor

Pharmaceuticals ◽

10.3390/ph14060542 ◽

2021 ◽

Vol 14 (6) ◽

pp. 542

Author(s):

Ehab El-Awaad ◽

Robin Birus ◽

Christelle Marminon ◽

Zouhair Bouaziz ◽

Laurens Ballentin ◽

...

Keyword(s):

Anticancer Activity ◽

Broad Spectrum ◽

Target Engagement ◽

Anticancer Activities ◽

Cellular Processes ◽

Pharmacokinetic Properties ◽

Substantial Progress ◽

A Cell ◽

Kinase Ck2 ◽

Ck2 Inhibitor

Protein kinase CK2 is involved in regulating cellular processes, such as cell cycle, proliferation, migration, and apoptosis, making it an attractive anticancer target. We previously described a prenyloxy-substituted indeno[1,2-b]indole (5-isopropyl-4-(3-methylbut-2-enyloxy)-5,6,7,8-tetrahydroindeno[1,2-b]indole-9,10-dione (4p)) as a very potent inhibitor of CK2 holoenzyme (IC50 = 25 nM). Here, we report the broad-spectrum anticancer activity of 4p and provide substantial progress on its pharmacokinetic properties. Using a cell-based CK2 activity assay and live-cell imaging of cultured A431, A549, and LNCaP cancer cell lines, cellular CK2 target engagement was shown as well as strong antiproliferative, anti-migratory and apoptosis-inducing effects of 4p. Furthermore, evidence was found for the ability of 4p to disrupt A549 spheroid cohesion. A series of LC-MS/MS experiments revealed high and rapid cellular uptake (intracellular concentration is approximately 5 µM after 1 h incubation) and low metabolic stability of 4p. These results point to the value of 4p as a potent CK2 inhibitor with promising anticancer activities and should trigger future medicinal chemistry efforts to improve the drug-like properties of this compound.

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Target engagement imaging of PARP inhibitors in small-cell lung cancer

Nature Communications ◽

10.1038/s41467-017-02096-w ◽

2018 ◽

Vol 9 (1) ◽

Cited By ~ 30

Author(s):

Brandon Carney ◽

Susanne Kossatz ◽

Benjamin H. Lok ◽

Valentina Schneeberger ◽

Kishore K. Gangangari ◽

...

Keyword(s):

Lung Cancer ◽

Small Cell Lung Cancer ◽

Cell Lung Cancer ◽

Parp Inhibitors ◽

Small Cell ◽

Target Engagement ◽

Small Cell Lung

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Design of a GAK/EGFR inhibitor set to interrogate the relationship of EGFR and GAK in chordoma

10.1101/475251 ◽

2018 ◽

Cited By ~ 2

Author(s):

Christopher R. M. Asquith ◽

Kaleb M. Naegeli ◽

Michael P. East ◽

Tuomo Laitinen ◽

Tammy M. Havener ◽

...

Keyword(s):

Epidermal Growth Factor Receptor ◽

Growth Factor Receptor ◽

Egfr Inhibitor ◽

Target Engagement ◽

Cell Target ◽

Epidermal Growth ◽

Cyclin G ◽

Relationship Of ◽

The Relationship

ABSTRACTWe describe the design of a set of inhibitors to investigate the relationship between cyclin G associated kinase (GAK) and epidermal growth factor receptor (EGFR) in chordoma bone cancers. These compounds were characterized both in vitro and using in cell target engagement assays. The most potent chordoma inhibitors were further characterized in a kinome-wide screen demonstrating narrow spectrum profiles.

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