FOS and gastric cancer: Finally, FKTN/fukutin mRNA and protein in gastric cancer [121] and FKTN mRNA in hepatic cancer [122, 123] have been found upregulated, fukutin presumably acting as a coactivator of the AP1 transcription factor (constituted by c-Fos and c-Jun), with ensuing upregulation of cyclin D1 expression and increase of cell proliferation [143].