Molecular Choreography and Structure of Ca(2+) Release-Activated Ca(2+) (CRAC) and K(Ca2+) Channels and Their Relevance in Disease with Special Focus on Cancer

Ca(2+) ions play a variety of roles in the human body as well as within a single cell. Cellular Ca(2+) signal transduction processes are governed by Ca(2+) sensing and Ca(2+) transporting proteins. In this review, we discuss the Ca(2+) and the Ca(2+)-sensing ion channels with particular focus on the structure-function relationship of the Ca(2+) release-activated Ca(2+) (CRAC) ion channel, the Ca(2+)-activated K(+) (K(Ca2+)) ion channels, and their modulation via other cellular components. Moreover, we highlight their roles in healthy signaling processes as well as in disease with a special focus on cancer. As K(Ca2+) channels are activated via elevations of intracellular Ca(2+) levels, we summarize the current knowledge on the action mechanisms of the interplay of CRAC and K(Ca2+) ion channels and their role in cancer cell development.