Since 2019, scientists have cultivated multiple organoid models on the International Space Station, including the human brain, heart, and breasts. These organoids are usually cultivated using human stem cells, and with the help of a series of chemical growth substances, stem cells can develop into three-dimensional structures similar to human tissue. Unlike traditional animal models such as mice or monkeys, organoids enable scientists to more accurately reproduce the unique complexity of human organs. The American Fun Science website recently reported that these organoids help scientists uncover the secrets of cancer, neurological disorders, and aging, and based on this, find better therapies. These organoids also help identify which compounds are effective for the human body, thereby accelerating the process of drug development. Why do scientists need to cultivate organoids in space to clarify the root causes of aging? One reason is that extreme space environments can help them study the relationship between human aging and disease. For many years, Professor Alison Muotri of the University of California, San Diego has been dedicated to sending human stem cells to the International Space Station to cultivate organoids that simulate various brain diseases. He explained that diseases such as Alzheimer's may have been lurking in humans for decades before their onset. But research has shown that the microgravity environment in space can accelerate the process of cell aging. Therefore, by studying brain like organs under microgravity conditions, they can determine how age-related changes occur and design therapies to prevent these changes based on this. The research on organoids by the Mutelli team was inspired by twin studies conducted by NASA. In twin studies, astronaut Scott Kelly went to space for a year, while his identical twin brother Scott Mark stayed on Earth. When Kelly returned to Earth, he showed signs of cognitive decline compared to his brothers. For example, he found it increasingly difficult to learn and remember. In an upcoming paper, the Mooteri team will describe the performance of their cultivated brain like organs on the International Space Station. He pointed out that these brain like organs exhibit characteristics of neurological diseases, such as degeneration and cellular stress. Detect tumor growth. Katrina Jamison, a medical professor at the University of California, San Diego, and her team are currently cultivating organoids in space, but they are not cultivating mini brains, but rather micro tumors. Research has found that after returning to Earth, Kelly's blood showed signs of telomere shortening, DNA damage, and some signaling molecules. These signaling molecules are believed to activate certain genes, causing cancer to grow and spread. Jamison stated that this suggests that pressure conditions in space may stimulate cancer growth in some way. Therefore, micro tumors cultivated in space may better reveal how cancer deteriorates. The Jamison team first sent blood stem cells into space, and just one month later, these cells showed signs of cancer related gene mutations. These mutations are related to abnormal cell growth and division. The researchers then sent a set of tumor like organ models of leukemia, colon cancer and breast cancer into space. It was found that these models also grew rapidly in space. The cells inside the organoid also opened ADAR1