ABSTRACT
There is an explosive and close to overwhelming array of preclinical and actual Phase I and Phase II clinical trials of biological agents for the therapy of human cancers. A new era of cancer therapeutics is taking its long-awaited place. At the cutting edge are naturally occurring attenuated and geneti-
cally engineered oncolytic viruses and viral vectors for gene therapy. Put in context, viral therapy of human cancers, tried and abandoned decades ago, re-emerges now to occupy a respectable position among these trials, even when the most sophisticated protocols of gene therapy with viral vectors [especially those with retro(lenti)viral vectors] are dealt with separately (regretfully not detailed in this volume, although we mention in this text some of the viral vectors that insert genes into the genome of cancer cells).
