The study, published in Molecular & Cellular Oncology, examined the anti-cancer potential and mechanism of action for oleocanthal, found in extra virgin olive oil (EVOO), after previous studies suggested that the phenolic compound kills cancer cells and that a diet high in EVOO is associated with a decreased risk of several cancers.
“We show that oleocanthal rapidly kills three different types of cancer cells (pancreatic, breast, prostate) but does not harm three different kinds of healthy cells,” study co-author Professor Paul Breslin from Rutgers University told NutraIngredients.
Breslin noted that while previous lab-based work has also suggested that oleocanthal can kill off cancerous cells while sparing healthy cells, no research has ever been able to offer an explanation of why.
“In our study we have figured out why … or at least one reason why,” he said. “The mechanism of killing the cancer cells is novel (lysosomal membrane permeabilisation) and is very interesting.”
“We think it may play a key role in why EVOO intake is associated with decreased risk of cancers in humans,” he suggested.
Lysosome rupture
The study, which was led by Onica LeGendre from Hunter College at The City University of New York, found that oleocanthal ruptures the lysosomes of cancer cells but not healthy cells in a process called lysosomal membrane permeabilization or LMP.
“The lysosome is a dumpster and recycling centre for waste in cells,” explained Breslin. “Because cancer cells are much more metabolically active and eat much more and grow faster than healthy cells, their lysosomes are by necessity much larger and apparently are more fragile.”
“When oleocanthal ruptures the lysosome a little bit, the acid and recycling enzymes chew up the cell a little bit and it goes into programmed cell death,” he noted – adding that the lysosomes of healthy cells are seemingly unaffected by oleocanthal.
“Amazingly, oleocanthal induced cell death in all cancer cells examined – as rapidly as 30 minutes after treatment in the absence of serum,” wrote the authors.
Indeed, the team suggested that the lysosomal membranes of cancerous cells are weaker than those of healthy cells, and therefore offer an explanation for why oleocanthal – and potentially other treatments – may be able to reverse cancer.
“We are very excited about this finding and now want to see if when oleocanthal is shrinking tumours in a live mouse model, it is doing so via action on the lysosomes of the cancer cells of the mice,” Breslin said.
He also suggested that as more people turn to the Mediterranean diet – which is known to be associated with a reduced risk of many different kinds of cancer – research may see oleocanthal from olive oil grow in its significance as a key active component of the diet.
Source: Molecular & Cellular Oncology
Published online ahead of print, doi: 10.1080/23723556.2015.1006077
“(-)-Oleocanthal rapidly and selectively induces cancer cell death via lysosomal membrane permeabilization (LMP)”
Authors: O LeGendre, P A S Breslin, D A Foster