Scientists from the University of Hiroshima have discovered a new compound in broccoli and other cabbages that could help fight certain types of cancer.
DIM, or 3,3'-diindolylmethane, causes controlled cell death and recycling of cellular components in fission yeast. Whether the DIM-induced damage mechanism persists in humans is not yet known.
"We found that the chemical compound DIM induces a new biological activity that damages the nuclear membranes in fission yeast," said Ueno, assistant professor at the Hiroshima Healthy Aging Research Center at the University of Hiroshima's Graduate School of Integrated Life Sciences.
“The integrity of nuclear membranes is important for human health,” says Ueno. “Mutations that cause defects in the nuclear membrane accelerate aging. Nuclear membranes also rupture and repair during cancer cell migration."
Part of the cell's repair process is called autophagy, or "self-eating." This is the degradation pathway of cellular components, in which the cell will consume its internal parts to conserve energy and optimize life processes.
Ueno also noted that autophagy is associated with both aging and age-related diseases. If the cell is defective, then it dies as a result of a programmed death process called apoptosis. Many cytotoxic cancer drugs act by inducing apoptosis, so being able to control this process could help maintain and improve human health, Ueno says.
"Our results indicate that the nuclear envelope may be one of the first targets of DIM," said author Parwane Emami, a PhD student at the University of Hiroshima's Graduate School of Integrated Life Sciences.
This conclusion is based on a previous report from a German research team that found that high concentrations of DIM increased the lifespan of fission yeast.
It may seem counterintuitive that an apoptosis-inducing compound could increase the lifespan of an organism, but Emami explained that DIM only appears to induce this behavior in exponentially dividing cells, such as cancer cells. If they die, the organism can live longer.
"Recent human studies indicate that DIM is a potential anti-cancer drug that acts by inducing apoptosis in various types of cancer, including breast, prostate, stomach, and pancreatic cancers," Ueno said.
“Research also shows that DIM induces autophagy in cancer cells. However, the effect of autophagy on tumor formation and progression is not fully understood. Understanding the mechanism of apoptosis and autophagy using DIM in fission yeast may be useful for the study of human cancer and the mechanisms of longevity.”
Researchers will continue to study the role of DIM in fission yeast.
"We want to understand how DIM damages the nuclear membranes of fission yeast, which could lead to the development of a first-in-class drug to kill cancer cells," said Emami.
"We also want to understand the mechanism of how DIM induces autophagy in fission yeast, which could contribute to understanding how to increase human lifespan."