Other Novel Therapies: Biomarkers, microRNAs and microRNA Inhibitors, DNA Methylation, Epigenetics, Immunotherapy and Virotherapy.

Neuroendocrine tumors (NETs) consist of heterogeneous neoplasms. The neuroendocrine cells of the human body are confined to certain organs, such as the thyroid, pancreas and adrenals, or they are dispersed throughout the body in the respiratory tract and in the intestinal mucosa. The cells belong to the diffuse endocrine cell system, share a neuroendocrine phenotype, and accumulate precursor molecules which are then processed into hormones, peptides or amines. The tightly controlled release on stimulation is either to the blood stream or adjacent cells or neurons. Neuroendocrine cells regulate various processes in the human body, such as gastrointestinal secretion, blood pressure and response to stress. NETs present a wide spectrum of malignant diseases from rather benign to very malignant and lethal variants. NETs may occur in any organ, but are mainly detected in the gastroenteropancreatic system and in the lungs. The understanding of NET biology and treatments has changed dramatically during the last decade. Today, the main problems that clinicians and translational scientists face in overcoming these malignancies relate to various aspects within the molecular pathogenesis of NETs. This chapter focuses on the importance of novel biomarkers: microRNA and microRNA inhibitors; DNA methylation and epigenetics, and immunotherapy and virotherapy to develop novel treatments for NETs.