On the basis of the agreement signed between UNESCO and the Government of the Republic of Poland the International Institute for Cell and Molecular Biology of UNESCO was officially inaugurated in October 1995 in Warsaw, Poland, as part of the activity of the Global Network for Molecular and Cell Biology (MCBN) of UNESCO. The occasion was marked by the bringing together in Warsaw of a broad spectrum of cell and molecular biologists from around the world under the auspices of the Global MCBN UNESCO. At the conclusion of that week-long celebration it became clear that Polish cell and molecular biology had come of age in terms of its depth, vigor and impact on the global scene. At the suggestion of Professor Angelo Azzi, chairman of Global MCBN UNESCO, we considered the challenge of compiling a volume in the Molecular and Cell Biology Updates tMCBU) Series that would address the molecular basis of cancer and its therapy, but one that would additionally serve to highlight Polish contributions to this field of research. We accepted the challenge presented to us by Professor Azzi and are grateful to all contributors of the present volume for making this a pleasant and stimulating project. We requested each contributor to present his personal perspective of respective topics. As a consequence, we hope that each contribution has a distinctive individual flavor which reflects the role played by individual research groups in advancing science.