Apoptotic and Necroptotic Mediators are Differentially Expressed in Mucinous and Non-Mucinous Colorectal Cancer

Emer O'Connell, Ian S Reynolds, Andreas U Lindner, Manuela Salvucci, Tony O'Grady, Orna Bacon, Sanghee Cho, Elizabeth McDonough, Daniel Longley, Fiona Ginty, Deborah A McNamara, John P Burke, Jochen H M Prehn

Research output: Contribution to journalArticlepeer-review

49 Downloads (Pure)

Abstract

Background: Mucinous colorectal cancer (CRC) represents 10% of all CRC and is associated with chemotherapy resistance. This study aimed to determine expression of apoptosis and necroptosis mediators in mucinous CRC.

Methods: RNA gene expression data were extracted from TCGA. Protein levels in 14 mucinous and 39 non-mucinous tumors were measured by multiplexed immunofluorescence. Levels of apoptosis and necroptosis signalling proteins were analysed in SW1463 (mucinous rectal), SW837 (non-mucinous rectal), LS174T (mucinous colon) and HCT116 (non-mucinous colon) cell lines by western blot. Cell death was investigated by flow cytometry measurement of propidium iodide stained cells.

Results: High cleaved-Caspase 3 expression was noted in resected mucinous tumors. Western blot identified alterations in apoptosis proteins in mucinous CRC, most prominently downregulation of Bcl-xL protein levels (p=0.029) which was also observed at the mRNA level in patients by analysis of TCGA gene expression data (p<0.001). Treatment with 5-FU did not significantly elevate cell death in mucinous cells, while non-mucinous cells showed robust cell death responses. However, 5-FU-induced phosphorylation of MLKL in mucinous cancer cells, suggestive of a switch to necroptotic cell death signaling.

Conclusion: Apoptotic and necroptotic mediators are differentially expressed in mucinous and non-mucinous colorectal cancers and represent targets for investigation of cell death mechanisms in the mucinous subtype.
Original languageEnglish
Article number815001
JournalFrontiers in Oncology
Volume12
DOIs
Publication statusPublished - 14 Jul 2022

Keywords

  • necroptosis
  • colorectal
  • apoptosis
  • chemotherapy
  • mucinous

Fingerprint

Dive into the research topics of 'Apoptotic and Necroptotic Mediators are Differentially Expressed in Mucinous and Non-Mucinous Colorectal Cancer'. Together they form a unique fingerprint.

Cite this