Researchers from the Salk Institute have come up with a new study that declares autophagy effective against cancer and tumor formation. It reveals that autophagy can potentially inhibit the formation of undying cancer cells. The research team was investigating the potential links between telomeres and the risk of cancer when they discovered this.
Adding to your information, autophagy is the natural process of reusing the damaged parts of cells for cell repair and regeneration. In addition, telomeres are the chromosomal caps that ensure that these genetic structures would not merge. Whenever a cell divides and makes a copy of its DNA, the telomeres get shorter. Eventually, they become so short that they could no longer protect the chromosomes. This is the time when the cell is signaled to halt cell division for good.
If the cell doesn’t receive such signal, it keeps dividing until the telomeres become too short or go missing. These kinds of cells enter “crisis.” It is a state where the uncapped chromosomes fuse and start malfunctioning e.g. like in cancer cells. The research team knew that crisis often causes cells to die in masses. This stops the pre-cancer cells from developing into full-blown cancer. Furthermore, they aimed at examining the mechanism of this advantageous process.
Many scientists assume that cell death in crisis may be an outcome of apoptosis. It, along with autophagy, is one of two types of programmed cell death. However, none of them evaluated these assumptions experimentally.
What do the results say?
This respective study involves experiments on human cells. For that purpose, the research team deactivated tumor-suppressor genes to limit cell division. It was observed that cells divided nonstop, their telomeres became dangerously short and triggered crisis. Afterward, the team evaluated the markers of autophagy and apoptosis to figure out which of the two kills cells in crisis.
According to the findings of the study, autophagy was the primary cause of cell death during crisis. Next, the researchers tested the consequences of inhibiting autophagy during crisis. They found that the cells continued to divide unstoppably since they could not die through autophagy.
The chromosomes of these cells ended up fused and deformed with their DNA damage resembling the severe genetic damage found in cancerous cells. In the end, the last part of the study called for imposing DNA damage to healthy cells.
The researchers intentionally damaged either the telomeres or the middle regions of the chromosomes. Consequently, they found that cells with damaged telomeres underwent autophagy. On the contrary, the cells, damaged at other parts of their chromosomes, underwent apoptosis.
Based on the findings of the study, the researchers concluded that autophagy is a mechanism that terminates pre-cancerous cells. It is activated when cells experience DNA damage or when the telomeres go too short or are already missing. However, autophagy can still be used as an effectual strategy even after cancer has already begun. This suggests the use of autophagy to kill a tumor by “starving” it.
The findings of the respective research study open up a new field of research, leading to the eventual discovery of a cure for cancer.