Heat-modified citrus pectin induces apoptosis-like cell death and autophagy in HepG2 and A549 cancer cells

Lionel Leclere, Maude Fransolet, Francois Cote, Pierre Cambier, Thierry Arnould, Pierre Van Cutsem, Carine Michiels

Research output: Contribution to journalArticlepeer-review

101 Downloads (Pure)

Abstract

Cancer is still one of the leading causes of death worldwide, and finding new treatments remains a major challenge. Previous studies showed that modified forms of pectin, a complex polysaccharide present in the primary plant cell wall, possess anticancer properties. Nevertheless, the mechanism of action of modified pectin and the pathways involved are unclear. Here, we show that citrus pectin modified by heat treatment induced cell death in HepG2 and A549 cells. The induced cell death differs from classical apoptosis because no DNA cleavage was observed. In addition, Z-VAD-fmk, a pan-caspase inhibitor, did not influence the observed cell death in HepG2 cells but appeared to be partly protective in A549 cells, indicating that heat-modified citrus pectin might induce caspase-independent cell death. An increase in the abundance of the phosphatidylethanolamine-conjugated Light Chain 3 (LC3) protein and a decrease in p62 protein abundance were observed in both cell types when incubated in the presence of heat-modified citrus pectin. These results indicate the activation of autophagy. To our knowledge, this is the first time that autophagy has been revealed in cells incubated in the presence of a modified form of pectin. This autophagy activation appears to be protective, at least for A549 cells, because its inhibition with 3-methyladenine increased the observed modified pectin-induced cytotoxicity. This study confirms the potential of modified pectin to improve chemotherapeutic cancer treatments.

Original languageEnglish
Article numbere0115831
JournalPLoS ONE
Volume10
Issue number3
DOIs
Publication statusPublished - 2015

Fingerprint

Dive into the research topics of 'Heat-modified citrus pectin induces apoptosis-like cell death and autophagy in HepG2 and A549 cancer cells'. Together they form a unique fingerprint.

Cite this