Polyamines are organic cations found in all eukaryotic cells and intimately involved in, and required for, distinct biological functions. An increasing body of evidence indicates that the regulation of cellular polyamines is a central convergence point for the multiple signaling pathways driving various cellular functions. Over the last decade, considerable progress has been made in und- standing the molecular functions of cellular polyamines. These significant findings provide a fundamental basis to not only define the exact role of polyamines in physiology, but also to develop new therapeutic approaches for cancers and other diseases. The major objective of this book is to provide a timely and long lasting guide for investigators in the fields of polyamines, physiology, pharmacology, and cancer research. It will provide a foundation based on research and address the potential for subsequent applications in clinical practice. Polyamine Cell Signaling: Physiology, Pharmacology, and Cancer Research is divided into four main parts: Part I: Polyamines in Signal Transduction of Cell Proliferation Part II: Polyamines in Cellular Signaling of Apoptosis, Carcinogenesis, and Cancer Therapy Part III: Polyamines in Cell Motility and Cell-Cell Interactions Part IV: Polyamine Homeostasis and Transport This book not only covers the current state-of-the-art findings relevant to cellular and molecular functions of polyamines, but also provides the underlying conceptual basis and knowledge regarding potential therapeutic targeting of polyamines and polyamine metabolism. These points are addressed by int- nationally recognized experts in their contributions to this book.

Polyamines are organic cations found in all eukaryotic cells and intimately involved in, and required for, distinct biological functions. An increasing body of evidence indicates that the regulation of cellular polyamines is a central convergence point for the multiple signaling pathways driving various cellular functions. Over the last decade, considerable progress has been made in und- standing the molecular functions of cellular polyamines. These significant findings provide a fundamental basis to not only define the exact role of polyamines in physiology, but also to develop new therapeutic approaches for cancers and other diseases. The major objective of this book is to provide a timely and long lasting guide for investigators in the fields of polyamines, physiology, pharmacology, and cancer research. It will provide a foundation based on research and address the potential for subsequent applications in clinical practice. Polyamine Cell Signaling: Physiology, Pharmacology, and Cancer Research is divided into four main parts: Part I: Polyamines in Signal Transduction of Cell Proliferation Part II: Polyamines in Cellular Signaling of Apoptosis, Carcinogenesis, and Cancer Therapy Part III: Polyamines in Cell Motility and Cell-Cell Interactions Part IV: Polyamine Homeostasis and Transport This book not only covers the current state-of-the-art findings relevant to cellular and molecular functions of polyamines, but also provides the underlying conceptual basis and knowledge regarding potential therapeutic targeting of polyamines and polyamine metabolism. These points are addressed by int- nationally recognized experts in their contributions to this book.

The mammalian gastrointestinal mucosa is a rapidly self-renewing tissue in the body, and its homeostasis is preserved through the strict regulation of epithelial cell proliferation, growth arrest, and apoptosis. The control of the growth of gastrointestinal mucosa is unique and, compared with most other tissue in the body, complex. Mucosal growth is regulated by the same hormones that alter metabolism in other tissues, but the gastrointestinal mucosa also responds to host events triggered by the ingestion and presence of food within the digestive tract. These gut hormones and peptides regulate the growth of the exocrine pancreas, gallbladder epithelium, and the mucosa of the oxyntic gland region of the stomach and the small and large intestines. Luminal factors, including nutrients or other dietary factors, secretions, and microbes that occur within the lumen and distribute over a proximal-to-distal gradient, are also crucial for maintenance of normal gut mucosal regeneration and could explain the villous-height-crypt-depth gradient and variety of adaptation, since these factors are diluted, absorbed, and destroyed as they pass down the digestive tract. Recently, intestinal stem cells, cellular polyamines, and noncoding RNAs are shown to play an important role in the regulation of gastrointestinal mucosal growth under physiological and various pathological conditions. In this book, we highlight key issues and factors that control gastrointestinal mucosal growth and homeostasis, with special emphasis on the mechanisms through which epithelial renewal and apoptosis are regulated at the cellular and molecular levels.