title: The tumor as an organ: comprehensive spatial and temporal modeling of the tumor and its microenvironment.
abstract: BACKGROUND
  Research related to cancer is vast, and continues in earnest in many directions. Due to the complexity of cancer, a better understanding of tumor growth dynamics can be gleaned from a dynamic computational model. We present a comprehensive, fully executable, spatial and temporal 3D computational model of the development of a cancerous tumor together with its environment.
  
  
  RESULTS
  The model was created using Statecharts, which were then connected to an interactive animation front-end that we developed especially for this work, making it possible to visualize on the fly the on-going events of the system's execution, as well as the effect of various input parameters. We were thus able to gain a better understanding of, e.g., how different amounts or thresholds of oxygen and VEGF (vascular endothelial growth factor) affect the progression of the tumor. We found that the tumor has a critical turning point, where it either dies or recovers. If minimum conditions are met at that time, it eventually develops into a full, active, growing tumor, regardless of the actual amount; otherwise it dies.
  
  
  CONCLUSIONS
  This brings us to the conclusion that the tumor is in fact a very robust system: changing initial values of VEGF and oxygen can increase the time it takes to become fully developed, but will not necessarily completely eliminate it.
authors.affiliation: Department of Computer Science and Applied Mathematics, Weizmann Institute of Science, 234 Herzl st, 7610001, Rehovot, Israel. Naamah.Bloch@weizmann.ac.il.
authors.forename: Naamah
authors.initials: N
authors.lastname: Bloch
authors.affiliation: Department of Computer Science and Applied Mathematics, Weizmann Institute of Science, 234 Herzl st, 7610001, Rehovot, Israel.
authors.forename: David
authors.initials: D
authors.lastname: Harel
mesh_terms: D003198:Computer Simulation; D018450:Disease Progression; D006801:Humans; D008954:Models, Biological; D009369:Neoplasms / Q000098:blood supply / Q000378:metabolism / Q000473:pathology; D009389:Neovascularization, Pathologic; D010100:Oxygen / Q000378:metabolism; D059016:Tumor Microenvironment; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D042461:Vascular Endothelial Growth Factor A; D010100:Oxygen
keywords: Biological systems; Computational models; Statecharts; Tumor and its microenvironment; Visualization