Oncotarget

Research Papers:

Neurotensin as a source of cyclic AMP and co-mitogen in fibrolamellar hepatocellular carcinoma

Kimberly J. Riehle _, Heidi L. Kenerson, Kevin M. Riggle, Rigney Turnham, Kevin Sullivan, Renay Bauer, John D. Scott and Raymond S. Yeung

PDF  |  Full Text  |  Supplementary Files  |  How to cite  |  Order a Reprint

Oncotarget. 2019; 10:5092-5102. https://doi.org/10.18632/oncotarget.27149

Metrics: PDF 490 views  |   Full Text 795 views  |   ?  


Abstract

Kimberly J. Riehle1, Heidi L. Kenerson1, Kevin M. Riggle1, Rigney Turnham2, Kevin Sullivan1, Renay Bauer1, John D. Scott2 and Raymond S. Yeung1

1 Department of Surgery, University of Washington, Seattle, WA, USA

2 Department of Pharmacology, University of Washington, Seattle, WA, USA

Correspondence to:

Kimberly J. Riehle,email: kriehle@uw.edu

Keywords: liver cancer; protein kinase A; fibrolamellar; neurotensin; epidermal growth factor

Received: March 04, 2019     Accepted: July 28, 2019     Published: August 20, 2019

ABSTRACT

Fibrolamellar hepatocellular carcinomas (FL-HCCs) possess a unique mutation that encodes a chimeric form of protein kinase A (DNAJ-PKAc), which includes a chaperonin binding domain. DNAJ-PKAc retains most of the biochemical properties of the native enzyme, however, and activity remains dependent on cAMP. We thus speculated that a persistent source of cAMP is necessary to promote FL-HCC carcinogenesis, and that neurotensin (NTS) may drive cAMP production in this setting, given that NS serum and tumor levels are elevated in many patients with FL-HCC.

We examined expression of NTS pathway components in human FL-HCCs and paired normal livers, and determined the role of NTS in driving proliferation in tumor slice cultures. Cultured hepatocytes were used to determine interactions between NTS and other proliferative pathways, and to determine the effects of NTS on cAMP production and PKA activity.

We found that the NTS pathway is up-regulated in human FL-HCCs, and that NTS activates cAMP and PKA in hepatocytes. NTS increases proliferation in the presence of epidermal growth factor (EGF), and NTS-induced proliferation is dependent on NTSR1 and the EGFR/MEK pathway.

We conclude that NTS serves as a co-mitogen in FL-HCC, and provides a source of cAMP to facilitate ongoing activation of DNAJ-PKAc.


Creative Commons License All site content, except where otherwise noted, is licensed under a Creative Commons Attribution 3.0 License.
PII: 27149