Mice lacking wild-type <i>Hras</i> develop more oncogenic Kras<i>-</i>driven skin tumors.

<p>(<b>A</b>) Representative photograph (white arrow) and (<b>B</b>) H & E stained section of facial papillomas that develop in KC mice. (<b>C</b>) Number of facial papillomas per <i>Hras</i>^<i>+/+</i> (n = 31) versus <i>Hras</i>^<i>-/-</i> (n = 28) KC mice (bar: mean ± S.E.M.). (<b>D</b>) % of total <i>Hras</i>^<i>+/+</i> and <i>Hras</i>^<i>-/-</i> KC mice (from <b>C</b>) that developed facial papillomas. (<b>E</b>) % facial papilloma-free survival of <i>Hras</i>^<i>+/+</i> (n = 45) versus <i>Hras</i>^<i>-/-</i> (n = 23) KPC mice. (<b>F</b>) % vulvar papilloma-free survival of <i>Hras</i>^<i>+/+</i> (n = 19) versus <i>Hras</i>^<i>-/-</i> (n = 11) female KPC mice. ***P<0.0001.