Nuclear factor-kappaB maintains TRAIL resistance in human pancreatic cancer cells.

Published

Journal Article

Although it displays promising activity in other tumor models, the effects of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) on human pancreatic cancer cells have not been comprehensively explored. We report that a majority of human pancreatic cancer cell lines (seven of nine) underwent apoptosis when they were exposed to recombinant human TRAIL in vitro. Characterization of surface TRAIL receptors by fluorescence-activated cell sorting showed that TRAIL-resistant cells (Panc-1 and HS766T) expressed lower levels of DR4 and DR5 than did TRAIL-sensitive cells. The proteasome inhibitor bortezomib (PS-341, Velcade) further increased TRAIL responsiveness in the TRAIL-sensitive cells and synergized with TRAIL to reverse resistance in Panc-1 and HS776T cells. The effects of bortezomib were mimicked by transfection with a small interfering RNA construct specific for the p65 subunit of nuclear factor-kappaB (NF-kappaB) or exposure to a selective chemical inhibitor of IKK (PS-1145). Silencing IkappaBalpha prevented TRAIL sensitization by PS-1145, confirming that IkappaBalpha mediated the effects of PS-1145. NF-kappaB inhibition resulted in down-regulation of BCL-XL and XIAP, and silencing either restored TRAIL sensitivity in TRAIL-resistant cells. Finally, therapy with TRAIL plus PS-1145 reversed TRAIL resistance in vivo to produce synergistic growth inhibition in orthotopic Panc-1 tumors. Together, our results show that NF-kappaB inhibits TRAIL-induced apoptosis in human pancreatic cancer cells and suggest that combination therapy with TRAIL and NF-kappaB inhibitors, such as bortezomib, PS-1145, or curcumin, should be considered as a possible treatment strategy in patients with pancreatic cancer.

Full Text

Duke Authors

Cited Authors

  • Khanbolooki, S; Nawrocki, ST; Arumugam, T; Andtbacka, R; Pino, MS; Kurzrock, R; Logsdon, CD; Abbruzzese, JL; McConkey, DJ

Published Date

  • September 2006

Published In

Volume / Issue

  • 5 / 9

Start / End Page

  • 2251 - 2260

PubMed ID

  • 16985059

Pubmed Central ID

  • 16985059

Electronic International Standard Serial Number (EISSN)

  • 1538-8514

International Standard Serial Number (ISSN)

  • 1535-7163

Digital Object Identifier (DOI)

  • 10.1158/1535-7163.mct-06-0075

Language

  • eng