Une étude montre pourquoi les jeunes générations sont plus sujettes au cancer

Study shows why younger generations may be more cancer-prone A growing body of research suggests that younger generations are experiencing a notable rise in cancer diagnoses, particularly among those under 50. This trend has been documented in both Germany and the United States, with experts pointing to a widening gap between biological and chronological age as a potential contributing factor. Susanna, a 28-year-old woman diagnosed with bowel cancer, and Andre, a 34-year-old man who developed lung cancer, are among the many young individuals affected. Their experiences highlight a broader pattern that scientists are now trying to understand. According to the German Cancer Research Center (DKFZ), there has been a marked increase in gastrointestinal cancer cases among individuals aged 20 to 39. Similar trends have been observed in the U.S., where the rate of such diagnoses appears even higher. Beyond gastrointestinal cancers, younger people are also being diagnosed with conditions affecting the bone marrow and uterus. These findings challenge the long-held belief that cancer primarily affects older adults. The average age for cancer diagnosis in both men and women is approximately 69, according to the German Cancer Aid, underscoring the unusual nature of these early-onset cases. Cancer typically develops due to mutations in genetic material that prevent cells from repairing themselves properly. As people age, the efficiency of these repair mechanisms declines, making them more susceptible to cancer. However, recent studies indicate that younger generations may be facing additional challenges. A team of researchers at Washington University School of Medicine in the U.S. has identified a possible connection between accelerated aging and increased cancer risk. They propose that younger people are aging faster than previous generations, leading to a greater disparity between their biological and chronological ages. Chronological age measures the number of years someone has lived, while biological age reflects the level of cellular damage and functional decline within the body. Different organs and tissues can age at varying rates, meaning that a person’s liver might show signs of advanced aging while their heart remains relatively youthful. Researchers analyzed data from over 150,000 participants in the UK Biobank, a large-scale biometric database. Their analysis revealed that individuals born between 1965 and 1974 exhibited a significantly larger gap between their chronological and biological ages compared to those born between 1950 and 1954. Ron Jachimowicz, an attending physician and hematologist at the University Hospital Cologne, and head of the Max Planck Research Group for Biology of Aging, explained that the study found a correlation between this age gap and the likelihood of developing early-onset cancer. While the study did not establish a direct cause-and-effect relationship, it provides valuable insights into the complex interplay between aging and cancer development. “This is a correlative study,” Jachimowicz cautioned. “Correlation means two factors appear together, but it doesn’t mean one causes the other.” Determining biological age involves assessing multiple indicators, including epigenetic markers, blood biomarkers, and telomere length. Telomeres, the protective caps at the ends of chromosomes, shorten as cells divide, and their length is often used as a marker of cellular aging. Other methods include evaluating organ function, cognitive performance, and metabolic health. By combining these approaches, researchers were able to identify patterns linking accelerated aging to heightened cancer risk. As the scientific community continues to explore the implications of these findings, public awareness and further research will play crucial roles in addressing the rising incidence of early-onset cancer. Understanding the factors behind this phenomenon could lead to earlier detection, improved treatment strategies, and better support for young cancer patients.