Abstract 4203: Kinase inhibitor demonstrates efficacy in patient derived xenograft model of fibrolamellar hepatocellular carcinoma featuring DNAJB1-PRKACA gene fusion

Abstract Background According to GLOBOSCAN, hepatocellular carcinoma (HCC) claimed 782,000 lives in 2018. The tyrosine kinase inhibitor sofafenib is used to treat HCC, but new anticancer agents targeting different pathways are urgently needed to improve outcomes for patients with advanced disease. The aberrant metabolism and aggressive growth of cancer cells can render them particularly susceptible to proteasome inhibition, as demonstrated by bortezomib treatment of multiple myeloma. However, resistance does emerge, and this 20S proteasome inhibitor has not proven active against HCC. The bis-benzylidine piperidone RA190 represents a novel class of proteasome inhibitor that covalently binds to cysteine 88 of RPN13, an ubiquitin receptor subunit of the proteasome’s 19S regulatory particle. RA190 treatment inhibits proteasome function, causing rapid accumulation of polyubiquitinated proteins. Considerable evidence suggests that nuclear factor κB (NF-κB) signaling, which is dependent upon the proteasome, is a major driver of inflammation-associated cancers, including HCC. Methods Human HCC cell lines were treated with titrations of RA190. The time course of endoplasmic reticulum stress and NF-κB-related mechanisms by which RA190 may trigger apoptosis were assessed. The therapeutic activity of RA190 was also determined in an orthotopic HCC xenograft mouse model. Results RA190 is toxic to HCC cells and synergizes with sofafenib. RA190 triggers rapid accumulation of polyubiquitinated proteins, unresolved endoplasmic reticulum stress, and cell death via apoptosis. RA190 blocks proteasomal degradation of IκBα and consequent release of NF-κB into the nuclei of HCC cells. Treatment of mice bearing an orthotopic HCC model with RA190 significantly reduced tumor growth. Conclusions RA190 has therapeutic activity in a xenograft model, and with sorafenib exhibited synergetic killing of HCC cells in vitro, suggesting further exploration of such a combination treatment of HCC is warranted.

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DNAJB1-PRKACA fusion kinase interacts with β-catenin and the liver regenerative response to drive fibrolamellar hepatocellular carcinoma

10.1101/192104 ◽

2017 ◽

Author(s):

Edward R. Kastenhuber ◽

Gadi Lalazar ◽

Shauna L. Houlihan ◽

Darjus F. Tschaharganeh ◽

Timour Baslan ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Gene Fusion ◽

Kinase Inhibitors ◽

Liver Tumors ◽

Tissue Injury ◽

Kinase Domain ◽

Wild Type ◽

Fibrolamellar Hepatocellular Carcinoma ◽

Genetic Event ◽

Genetic And Environmental Factors

AbstractA segmental deletion resulting in DNAJB1-PRKACA gene fusion is now recognized as the signature genetic event of fibrolamellar hepatocellular carcinoma (FL-HCC), a rare but lethal liver cancer that primarily affects adolescents and young adults. Here, we implement CRISPR/Cas9 genome editing and transposon-mediated somatic gene transfer to demonstrate that expression of both the endogenous fusion protein or a chimeric cDNA leads to the formation of indolent liver tumors in mice that closely resemble human FL-HCC. Notably, overexpression of the wild type PRKACA was unable to fully recapitulate the oncogenic activity of DNAJB1-PRKACA, implying that FL-HCC does not simply result from enhanced PRKACA expression. Tumorigenesis was significantly enhanced by genetic activation of β-catenin, an observation supported by evidence of recurrent Wnt pathway mutations in human FL-HCC, as well as treatment with hepatotoxin 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC), which causes tissue injury, inflammation and fibrosis. Our study validates the DNAJB1-PRKACA fusion kinase as an oncogenic driver and candidate drug target for FL-HCC and establishes a practical model for preclinical studies to identify strategies to treat this disease.SignificanceEfforts to understand and treat FL-HCC have been confounded by a lack of models that accurately reflect the genetics and biology of the disease. Here, we demonstrate that the Dnajb1-Prkaca gene fusion drives tumorigenesis in mice, and that fusion to DNAJB1 drives FL-HCC initiation more effectively than wild type PRKACA overexpression. The requirement of the PRKACA kinase domain in tumor initiation establishes the potential utility of kinase inhibitors targeting the fusion. By identifying genetic and environmental factors that can enhance the consistency and aggressiveness of disease progression, we reveal biological characteristics of the disease and advance a robust platform for future pre-clinical studies.

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A Patient-Derived Xenograft Model of Parameningeal Embryonal Rhabdomyosarcoma for Preclinical Studies

Sarcoma ◽

10.1155/2015/826124 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 6

Author(s):

Jody E. Hooper ◽

Emma L. Cantor ◽

Macgregor S. Ehlen ◽

Avirup Banerjee ◽

Suman Malempati ◽

...

Keyword(s):

Kinase Inhibitor ◽

Single Agent ◽

Xenograft Model ◽

Soft Tissue Sarcomas ◽

Preclinical Study ◽

Embryonal Rhabdomyosarcoma ◽

Rapid Weight Loss ◽

Primary Tumor Site ◽

Immunodeficient Mice ◽

Patient Derived Xenograft

Embryonal rhabdomyosarcoma (eRMS) is one of the most common soft tissue sarcomas in children and adolescents. Parameningeal eRMS is a variant that is often more difficult to treat than eRMS occurring at other sites. A 14-year-old female with persistent headaches and rapid weight loss was diagnosed with parameningeal eRMS. She progressed and died despite chemotherapy with vincristine, actinomycin-D, and cyclophosphamide plus 50.4 Gy radiation therapy to the primary tumor site. Tumor specimens were acquired by rapid autopsy and tumor tissue was transplanted into immunodeficient mice to create a patient-derived xenograft (PDX) animal model. As autopsy specimens had an ALK R1181C mutation, PDX tumor bearing animals were treated with the pan-kinase inhibitor lestaurtinib but demonstrated no decrease in tumor growth, suggesting that single agent kinase inhibitor therapy may be insufficient in similar cases. This unique parameningeal eRMS PDX model is publicly available for preclinical study.

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Heterogeneous Binding and Central Nervous System Distribution of the Multitargeted Kinase Inhibitor Ponatinib Restrict Orthotopic Efficacy in a Patient-Derived Xenograft Model of Glioblastoma

Journal of Pharmacology and Experimental Therapeutics ◽

10.1124/jpet.117.243477 ◽

2017 ◽

Vol 363 (2) ◽

pp. 136-147 ◽

Cited By ~ 10

Author(s):

Janice K. Laramy ◽

Minjee Kim ◽

Shiv K. Gupta ◽

Karen E. Parrish ◽

Shuangling Zhang ◽

...

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Kinase Inhibitor ◽

Xenograft Model ◽

Patient Derived Xenograft

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Bis-benzylidine Piperidone RA190 Treatment of Hepatocellular Carcinoma via Binding RPN13 and Inhibiting NF-κB Signaling

10.21203/rs.2.18702/v4 ◽

2020 ◽

Author(s):

Ruey-Shyang Soong ◽

Ravi K. Anchoori ◽

Richard B. S. Roden ◽

Rou-Ling Cho ◽

Yi-Chan Chen ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Endoplasmic Reticulum ◽

Endoplasmic Reticulum Stress ◽

Proteasome Inhibitor ◽

Time Course ◽

Kinase Inhibitor ◽

Xenograft Model ◽

Therapeutic Activity ◽

Rapid Accumulation ◽

Hcc Cells

Abstract Background According to GLOBOSCAN, hepatocellular carcinoma (HCC) claimed 782,000 lives in 2018. The tyrosine kinase inhibitor sofafenib is used to treat HCC, but new anticancer agents targeting different pathways are urgently needed to improve outcomes for patients with advanced disease. The aberrant metabolism and aggressive growth of cancer cells can render them particularly susceptible to proteasome inhibition, as demonstrated by bortezomib treatment of multiple myeloma. However, resistance does emerge, and this 20S proteasome inhibitor has not proven active against HCC. The bis-benzylidine piperidone RA190 represents a novel class of proteasome inhibitor that covalently binds to cysteine 88 of RPN13, an ubiquitin receptor subunit of the proteasome’s 19S regulatory particle. RA190 treatment inhibits proteasome function, causing rapid accumulation of polyubiquitinated proteins. Considerable evidence suggests that nuclear factor κB (NF-κB) signaling, which is dependent upon the proteasome, is a major driver of inflammation-associated cancers, including HCC. Methods Human HCC cell lines were treated with titrations of RA190. The time course of endoplasmic reticulum stress and NF-κB-related mechanisms by which RA190 may trigger apoptosis were assessed. The therapeutic activity of RA190 was also determined in an orthotopic HCC xenograft mouse model. Results RA190 is toxic to HCC cells and synergizes with sofafenib. RA190 triggers rapid accumulation of polyubiquitinated proteins, unresolved endoplasmic reticulum stress, and cell death via apoptosis. RA190 blocks proteasomal degradation of IκBα and consequent release of NF-κB into the nuclei of HCC cells. Treatment of mice bearing an orthotopic HCC model with RA190 significantly reduced tumor growth. Conclusions RA190 has therapeutic activity in a xenograft model, and with sorafenib exhibited synergetic killing of HCC cells in vitro , suggesting further exploration of such a combination treatment of HCC is warranted.

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