The role of Leptin in laryngeal squamous cell carcinoma

Leptin is a peptide produced by peptidergic cells or those able to process and secrete peptides. Originally, this function was considered proper and exclusive of certain neurons of the magnocellular and parvicellular hypothalamus. These cells originated from a common precursor, namely neural crest cells, which have the ability to produce hormonal neuropeptides. From this primitive neuroectodermal site, cells migrate to other organs: the gastro-entero-pancreatic system (GEP), the lung, heart, reproductive and urinary systems. Leptin is considered the typical neuropeptide with an anorexic function, and is also called the “satiety hormone” because it plays a key role in the control of energy expenditure and food intake. Leptin was identified for the first time in white and brown adipocytes. Although initially thought to be exclusively expressed and secreted by adipocytes, leptin has been identified in other tissues related with nutritional homeostasis, such as gastric and salivary glands. In addition, leptin or its receptors have been observed in gastric, colorectal and breast cancers. It is believed to have a role in stimulating cell proliferation, and is associated with a risk of developing cancer as well as progression and invasiveness. To date, the role of leptin in the development of the carcinoma of the larynx has been poorly investigated. The principal endpoint of this chapter was to evidence the peptidergic immunohistochemical expression of leptin in laryngeal SCCs, its possible role in cell proliferation and the prognostic factor and predictor of locoregional recurrences.