Humans have been fighting against tumors for more than 100 years, and treatments such as surgery, chemotherapy and radiotherapy have been introduced one after another, and new therapeutic techniques such as immunotherapy, targeted therapy and gene therapy have also emerged one after another. In the midst of a series of intensive attacks on tumors, some scientists are proposing an eye-opening method of prevention and treatment: happiness! A series of new evidence at home and abroad has found that mental factors are not only related to emotions, but also have a subtle connection with neuromodulation, immune system, hormone secretion, and eventually cancer development. Based on this new understanding of tumor development, scientists have proposed a new path for tumor prevention and treatment. Tumors in “happy mice” became smaller and even disappeared Cancer death is a daunting topic. Jianren Gu mentioned three “1/3” statements: 1/3 patients die from the natural law of cancer development, such as 90% die from metastasis; 1/3 patients die from over-treatment, which destroys the person; 1/3 patients die from fear and high depression, which we often say “scared to death”. “The first two points are the major problems of cancer prevention and treatment. The first two points are the difficulties and hot spots of tumor prevention and treatment, and the last point is of special concern to Gu Jianren. In 2010, the journal Cell published the findings of a foreign laboratory. Laboratory personnel put a group of mice in an “enriched living environment”, i.e., cages with various mice’s favorite toys, and more than 8 mice in each cage to ensure that they interact with each other to their heart’s content. The mice living in this state are called “happy mice”. Comparing the “happy mice” with the control mice, the researchers found that the tumors in the “happy mice” were smaller, proving that benign mental stimulation had an inhibitory effect on the tumors. The researchers suggested a “magical pathway”: benign cortical stimulation – hippocampus (the “happy mice” had high expression of “brain-derived neurotrophic factor”) – autonomic nerves (mainly sympathetic) – fat. mainly sympathetic nerves)-adipose tissue (adipokines)-tumor suppression. The experiments involved melanoma, pancreatic cancer, colon polyposis, etc. Recently, Tu Hong and Gan Yu’s research group at Shanghai Cancer Institute, further validated the foreign findings. The researchers also created a “rich living environment” during the rearing of the rats, placing mazes, toys, houses and pulleys in the rearing cages. Under the infrared photography, the reporter saw that the mice not only play during the day, but also play a lot at night, active performance; while the control group mice appear calm and even a little sluggish. Comparing the two groups of mice, we found that the tumor weight of the “happy mice” was lower than that of the control group, and some tumors not only became smaller, but also disappeared. The experiment involved melanoma, pancreatic cancer, and lung cancer all had a similar situation. The tumor suppression rate was 43.1% for melanoma, 58.2% for Panc02 pancreatic cancer, and 36.5% for Lewis lung cancer. The researchers also found high expression of “brain-derived neurotrophic factor” in the hypothalamus of “happy mice”. In a few scattered laboratories around the world, scientists are gaining new evidence for the association of central regulatory systems with tumors. The Shanghai Institute of Oncology recently found that “benign mental stimulation may alter the metabolism of cancer cells while affecting the immune system.” This suggests that mental behavior may have an impact on tumors. It is necessary for us to reconceptualize tumors as they find opportunities to form independent kingdoms in the body. “The traditional concept of cancer is that it is an autonomous abnormal growth of local tissues: stomach cancer is what is wrong with the stomach, liver cancer is what is wrong with the liver. That was the view more than a century ago, the golden rule at that time, and coming to today, it’s going to change.” According to Jianren Gu, there is growing evidence that cancer is a systemic disease. In 2004 and 2005, Jianren Gu and academician Shengli Yang proposed in the Proceedings of the National Academy of Sciences and the Chinese Medical Journal that cancer is a systemic systemic dysregulated disease characterized by abnormal local tissue growth. Gu Jianren has made an image analogy: the formation of tumor is the result of the central regulatory system “not acting” and the peripheral organs/tissues “acting”. The tumor is the “triad”, which expands itself, destroys the social stability and the police system (immune system). The human immune system is supposed to attack cancer cells, but it is “abetted” by tumor and turned into its umbrella. “Tumor is like forming an independent kingdom in the body, which is the root cause of the difficulty of tumor treatment.” In December 2012, Professor J.van.de.Greef, a Dutch authority in systems biology, wrote to Jianren Gu, affirming the importance of the concept of systemic regulation. “We believe that multidimensional regulation is of great importance in biology and cancer. This dynamic study of regulatory systems offers new avenues for the development of biological sciences.” “Cancer is the result of a central and local systemic regulatory imbalance in the organism, and the establishment of rebalancing is the key to future individual treatment.” Gu Jianren emphasized the role of psychologically benign environment on the formation of rebalancing, which requires benign interaction between doctors and patients, as well as drug-assisted treatment, for example, anti-anxiety and “happiness” drugs can be considered for patients in the future. More than ten years ago, the World Health Organization proposed the explanation of three “1/3” of cancer, that is, 1/3 of cancer patients can be prevented and treated through primary prevention; 1/3 of cancer can be significantly improved and even cured through secondary prevention. Survival rate can be significantly improved or even cured through secondary prevention; 1/3 of cancers can be improved through reasonable comprehensive treatment. “This idea was proposed more than 10 years ago, and it seems visionary today.” Using primary prevention as an example, Gu Jianren explained that smoking can easily cause lung cancer, and blocking this behavior of smoking can prevent lung cancer, which is called primary prevention. Primary prevention prevents and controls the occurrence of cancer, including external and internal factors. Exogenous factors refer to environmental factors, such as smoking, alcohol consumption, excessive nutrition and lack of physical activity. Researcher Yongbing Xiang of Shanghai Cancer Institute recently published four consecutive articles revealing that obesity and type 2 diabetes are closely related to liver cancer and pancreatic cancer. The internal causes include neurological/hormonal/immune system disorders in addition to the more familiar genetic factors. This again suggests an association between neurological stress and cancer, which has been a particular concern for scientists in recent years. In 2000, LeeHood proposed the concept of “4P medicine”, which is “preventive medicine”, “predictive medicine”, “individual medicine”, and “participatory medicine”. It is an acronym for “preventive medicine”, “predictive medicine”, “individual medicine”, and “participatory medicine”. Recently, the National Institutes of Health proposed “precision medicine”, which is developed on the basis of “predictive medicine” and “individual medicine”. It is worth noting that 4P medicine puts forward the concept of “participatory medicine”, emphasizing the participation of patients. “For many years, patients have been passive and listened to doctors. According to Gu, “participatory medicine” includes not only the active participation of patients in choosing treatment plans, but more importantly, it emphasizes spiritual guidance, medication and more interaction between patients and doctors. Gu Jianren expressed his appreciation for the post-treatment psychological counseling for tumor patients at the Cancer Hospital of Fudan University. Scientific researchers have recognized that tumor treatment is a process of re-establishing the equilibrium state of the organism, among which, mental factors have a subtle relationship to the development of cancer, which requires doctors to pay attention to the mental state of patients. It is not enough to focus only on the tumor itself, but also on the person who has the tumor. “Seeing the disease but not the person” may be a misconception that we must correct in our understanding and practice. Happy, in a sense, may be a revolution for tumor prevention and treatment.