Core Viewpoint - The article discusses a groundbreaking study published in Nature by a team led by Academician Zhang Zemin, focusing on the concept of "cross-tissue cellular modules" and their role in multicellular coordination within human tissues, particularly in the context of cancer progression [2][16]. Group 1: Research Background - The study integrates single-cell transcriptomic data from 706 healthy samples across 35 human tissues, creating the most comprehensive cross-tissue single-cell atlas to date, covering 2.29 million cells [8][16]. - The research identifies significant differences in cellular composition across various healthy tissues, revealing 12 distinct cross-tissue cellular modules (CMs) with unique cellular compositions and distributions [9][16]. Group 2: Cellular Modules and Their Functions - The identified cellular modules include CM04, CM05, CM06, and CM09, which are abundant in primary and secondary immune organs, indicating their roles in immune cell production and maturation [10][13]. - Other modules, such as CM02 and CM03, are primarily found in the urinary system and gastrointestinal tract, while CM08 is enriched in barrier tissues like skin and mucosal surfaces, suggesting their specific functional roles [10][11]. Group 3: Spatial Dynamics and Aging - The study employs spatial transcriptomics to illustrate how these cellular modules are spatially organized within tissues, highlighting their functional roles in maintaining tissue homeostasis [14][16]. - Notably, the immune cell modules CM05 and CM06 exhibit contrasting temporal dynamics with aging, where CM05 increases while CM06 decreases, indicating their potential as biomarkers for age-related changes [14][16]. Group 4: Implications for Cancer Research - The research extends to the tumor microenvironment (TME), analyzing single-cell transcriptomic data from 1,062 clinical samples across 29 cancer types, identifying 91 cell subpopulations [15][16]. - It reveals a dual remodeling of cellular modules during tumor progression, where healthy tissue-specific modules are lost, and cancer-associated modules emerge, providing insights into the fundamental organizational principles of multicellular ecosystems in health and disease [15][16].