Zurich – Swiss researchers have identified two signal proteins which are essential for maintaining primary ciliae on kidney epithelia cells (Nat Cell Biol. 2007 May;9(5):588-95). The antennae-like structures are involved in suppressing cancerous growth of kidney epithelia cells and kidney cyst formation. When the researchers under Claudio Thoma from ETH Zurich inactivated either the VHL tumour suppressor gene or the gene that codes the kinase glycogen synthase kinase (GSK)3beta, one gene product compensated for the loss of the other. But when the researchers inhibited both genes, the cilia disappeared and model mice developed kidney cysts. Currently, it is unclear how the cancer arises from kidney cysts.