A novel function of Kindlin-3 in cancer

Kindlin-3 (FERMT-3) is a key integrin activating protein belonging to the Kindlin family which includes three members Kindlin-1, 2 and 3. Kindlins can directly bind to various classes of integrins and participate in their activation, thus playing a key role in the regulation of cell-matrix adhesions. Kindlin-3 has been known to be central in the control of hemostasis and thrombosis as its deficiency disrupts platelet aggregation and causes Leukocyte Adhesion Deficiency disease. Its expression has so far been only described in hematopoietic cells, and more recently in endothelial cells. The current manuscript highlights key findings from our recent research describing a novel role of Kindlin-3 as a tumor suppressor in cancer. We present data showing that Kindlin-3 is expressed more ubiquitously than previously thought, and that through gene inactivation mechanisms, its expression is significantly reduced in several human solid cancer lesions. The increase in the malignant properties of tumor cells when Kindlin-3 expression is silenced and the inverse expression of Kindlin-3 with the tumor promoter EMMPRIN/CD147 corroborate the tumor suppressor role of Kindlin-3. A schematic model based on our research data describing Kindlin-3 mode of action in tumor cells is presented.