Apoptosis

, Volume 19, Issue 3, pp 527–541

Resveratrol induced ER expansion and ER caspase-mediated apoptosis in human nasopharyngeal carcinoma cells

  • Shu-Er Chow
  • Cheng-Heng Kao
  • Yi-Tong Albert Liu
  • Mei-Ling Cheng
  • Ya-Wen Yang
  • Yao-Kuan Huang
  • Chih-Chin Hsu
  • Jong-Shyan Wang
Original Paper

DOI: 10.1007/s10495-013-0945-0

Cite this article as:
Chow, S., Kao, C., Liu, Y.A. et al. Apoptosis (2014) 19: 527. doi:10.1007/s10495-013-0945-0

Abstract

Autophagy and endoplasmic reticulum (ER) stress response is important for cancer cells to maintain malignancy and resistance to therapy. trans-Resveratrol (RSV), a non-flavonoid agent, has been shown to induce apoptosis in human nasopharyngeal carcinoma (NPC) cells. In this study, the involvements of tumor-specific ER stress and autophagy in the RSV-mediated apoptosis were investigated. In addition to traditional autophagosomes, the images of transmission electron microscopy (TEM) indicated that RSV markedly induced larger, crescent-shaped vacuoles with single-layered membranes whose the expanded cisternae contains multi-lamellar membrane structures. Prolonged exposure to RSV induced a massive accumulation of ER expansion. Using an EGFP-LC3B transfection and confocal laser microscopy approach, we found RSV-induced EGFP-LC3 puncta co-localized with ER-tracker red dye, implicating the involvement of LC3II in ER expansion. The proapoptotic effect of RSV was enhanced after suppression of autophagy by ATG7 siRNA or blocking the autophagic flux by bafilomycin A1, but that was not changed after targeted silence of IRE1 or CHOP by siRNA. Using caspase inhibitors, we demonstrated the upregulation of caspase-12 (casp12) and the activation of casp4 were associated with the proapoptotic induction of RSV through the caspase-9/caspase-3 pathway. Intriguingly, siRNA knockdown of casp12, but not caspase-4, decreased the susceptibility of the NPC cells to RSV-mediated apoptosis. Further, we showed that RSV dose-dependently increased the ceramide accumulation as assessed by LC–MS/MS system. Using serine palmitoyltransferase (SPT, a key enzyme of de novo ceramide biosynthesis) inhibitors (l-cycloserine and myriocin), we found the increased ceramide accumulation was strongly correlated with the proapoptotic potential of RSV. This study revealed the ER expansion and upregulation of ER casp12 together may indicate profound biological effects of RSV and contributed to NPC cell death. Targeting the different status of ER stress may provide a possible strategy for cancer treatments.

Keywords

ResveratrolER expansionCaspase-12ApoptosisNPCAutophagy

Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Shu-Er Chow
    • 1
    • 2
  • Cheng-Heng Kao
    • 1
  • Yi-Tong Albert Liu
    • 3
  • Mei-Ling Cheng
    • 2
    • 4
  • Ya-Wen Yang
    • 1
  • Yao-Kuan Huang
    • 1
  • Chih-Chin Hsu
    • 5
  • Jong-Shyan Wang
    • 2
    • 6
  1. 1.Department of Nature Science Center for General StudiesChang Gung UniversityTaoyuanTaiwan
  2. 2.Healthy Aging Research CenterChang Gung UniversityTaoyuanTaiwan
  3. 3.School of MedicineUniversity of New MexicoAlbuquerqueUSA
  4. 4.Department of Biomedical SciencesChang Gung UniversityTaoyuanTaiwan
  5. 5.Department of Physical Medicine and RehabilitationChang Gung Memorial HospitalKeelungTaiwan
  6. 6.Graduate Institute of Rehabilitation ScienceChang Gung UniversityTaoyuanTaiwan