This review will examine the roles of prokineticins in the different neoplasms that have been investigated and will discuss how and why the prokineticin family presents such interesting prospects in the research against cancer. Prokineticins belong to a family of highly conserved small peptides (8 kDa) discovered a decade ago in frog skin secretions and snake venom. The mammalian orthologs consist of two prokineticin peptides, prokineticin 1 (PROK1) and prokineticin 2 (PROK2) that signal through two G-protein coupled receptors: prokineticin receptor 1 (PROKR1) and prokineticin receptor 2 (PROKR2). Over the last decade of research, the PROK/PROKR system has been associated with a considerable number of physiological and pathological functions. Due to this wide spectrum of functions, notably potent angiogenic and immunoregulatory activities, numerous investigators have researched the PROK/PROKR system’s role in cancer development in a variety of tissues.