Malignant growth of cells is often characterized by disorganization of tissue structure, abnormal blood vessel development, and insuffi cient vascular supply. As a consequence, the cancer cells grow in a three-dimensional pattern in atypical microenvironments which include physical, chemical, and nutritional stresses. Necrosis often develops some distance away from the blood vessels. In association with an inherent instability in malignant cell populations, and also because of the changing micromilieu, significant cellular heteroge neity emerges with regard to various phenotypic characteristics. Both biological behavior and responses to therapeutic agents can be affected. A variety of in vitro and in vivo experimental models exist for research on properties of cancer cells during growth. The multicell spheroid model was developed as a system of intermediate complexity in which three dimensional growth of cells enhances cell-cell interactions and creates micro environments that simulate the conditions in intervascular microregions of tumors or microme tastatic foci. Spheroids may change their cellular characteristics with changing environments during growth. These can be studied under controlled conditions in vitro. Interest in details of experimental methods for this model system stimulated the organization of the First International Conference in Rochester, NY in 1980, the Proceedings of which were summarized in Cancer Research in 1981. Since then there has been a rapid increase in the use of this model system, and increased research on the significance of cell-cell and cell-microenvironment interactions in biology in general.

Klappentext

Sponsored by the Swiss League against Cancer

Inhalt
Liquid-Overlay Culture of Cellular Spheroids.- Growth and Cellular Characteristics of Multicell Spheroids.- Regulatory Mechanisms in Spheroidal Aggregates of Normal and Cancerous Cells.- Intercellular Communication in Spheroids.- Spheroids for Studies of Drug Effects.- Radiation Studies with Spheroids.- Microenvironmental Conditions in Multicellular Spheroids Grown Under Liquid-Overlay Tissue Culture Conditions.- Microelectrode Measurements of Oxygen Tension Distributions in Multicellular Spheroids Cultured in Spinner Flasks.- Profiles of Oxygen Partial Pressure and Oxygen Consumption Inside Multicellular Spheroids.- Oxygen Supply to Spheroids in Spinner and Liquid-Overlay Culture.- Modeling and Simulation of Growing Spheroids.