Major breakthrough! Chinese scientists reveal new mechanism of cell death caused by radiation damage

Author Duan Yuechu

Radiation is everywhere in the world we live in. From cosmic rays to X-rays in medical examinations, from mobile phone signals to microwave radiation, although most of these radiations are within a safe range, once excessive, they can cause serious harm to our bodies. One of the main hazards of radiation is that it causes DNA damage, which in turn leads to a series of serious consequences such as cell death, affecting the normal physiological functions of the human body and even causing major diseases such as cancer.

On February 13, 2025, Chinese scientists published a remarkable new study in the British journal Cell Death and Differentiation. This study revealed the key mechanism by which the STING (stimulator of interferon genes) protein drives cell death after radiation by binding to the product molecule PAR (polyadenosine diphosphate ribose) synthesized by the DNA damage response protein PARP1. This discovery is like lighting a bright light in the dark, providing us with a new perspective for a deeper understanding of radiation damage and the treatment of related diseases.

High-dose radiotherapy has always been a common and effective means of treating pelvic and abdominal tumors. However, it is like a double-edged sword. While killing cancer cells, it often causes patients to suffer from severe gastrointestinal syndromes, such as intestinal mucosal detachment, bleeding, and even multiple organ failure. Traditional protective measures mainly rely on physical shielding and antioxidants, but such measures have limited effect in preventing radiation-induced programmed cell death. For a long time, scientists have been like walkers groping in the dark, trying to find the "switch" that regulates the DNA damage response. As a core molecule of innate immunity, the STING protein has gradually attracted the attention of the scientific community for its relationship with cell death, but the mechanism behind it has always been as mysterious and unclear.

This time, Chinese scientists used the radiation damage model to discover that STING is like a "death switch" that triggers the cell's "suicide program" by "capturing" a large number of product molecules PAR synthesized by PARP1 protein after DNA damage. This is an extremely delicate and complex process. PARP1 is activated after DNA damage and rapidly synthesizes PAR molecules, while STING protein accurately recognizes and binds to these PAR molecules, thereby initiating a series of signal transductions, ultimately leading to cell death.

To verify the practical application value of this discovery, the research team conducted animal experiments. The results were exciting. The use of PARP1 inhibitor PJ34 can reduce PAR production by 80%, thereby reducing the STING-mediated apoptosis pathway and greatly reducing cell death and radiation damage. This result is like a key that opens a new door for us to protect against radiation damage and treat cancer.

This research result has significant value and role in many aspects. In terms of radiation damage protection, the development of STING inhibitors or PARP1 regulatory drugs can protect normal tissues from tumor radiotherapy damage like a solid shield. For patients who suffer great pain from radiotherapy, this is undoubtedly a blessing and is expected to significantly improve their quality of life. In terms of enhancing the efficacy of cancer treatment, activating the PARP1-PAR-STING pathway locally in the tumor is like putting a "death label" on cancer cells, which can enhance the "targeted clearance" effect of radiotherapy on cancer cells. By precisely regulating the activity of this pathway, it will even be possible to achieve intelligent switching between "protecting normal tissues" and "killing cancer cells" in the future, making cancer treatment more accurate and efficient.

From a more macroscopic perspective, this study has laid a solid theoretical foundation for the safe use of radiotherapy to treat tumors and prevent radiation damage caused by nuclear accidents, and has provided a new treatment idea. In the future, perhaps we will be able to develop safer and more effective radiotherapy adjuvant drugs so that cancer patients no longer suffer too many side effects during treatment; in the face of emergencies such as nuclear accidents, there will also be more effective medical treatment plans to minimize the damage of radiation to the human body.

In short, this research result of Chinese scientists is a major breakthrough in the field of radiation biology and cancer treatment, which brings us new hope and direction. I believe that in the near future, new technologies and new drugs based on this research result will continue to emerge and make great contributions to human health.