The enhanced tyrosine phosphorylation of p190B regulates chromosomal segregation in the PTEN-null cancer cells.20 The hyperactive p190A perturbs cytokinesis.19 Similarly, the highly activating p190B by MCT-1 may cause disproportional contraction of the mitotic furrow site, resulting in asymmetrical cell division, chromosomal miss-segregation and cytokinesis failure. Here, ARHGAP5 is linked to cancer.