Expression of the placenta-specific, 100 kDa ras GTPase activating protein in several human cancer cell lines and normal human tissues

The ras GTPase activating protein (ras GAP), a regulator of Ras activity, has two isoforms; ras GAP 120 and ras GAP 100. The latter, whose molecular size is about 100 kDa, is generated alternative splicing from the ras GAP 120 gene and is considered placenta-specific, while the former is expressed ubiquitously.