<i>Pdx1-Cre;LSL-Kras</i>^{<i>G12D/+</i>}<i>;Trp53</i>^{<i>flox/wt</i>}<i>;Ksr1</i>^<i>-/-</i> mice develop PanIN lesions at similar rates and severity to <i>Ksr1</i>^<i>+/-</i> and <i>Ksr1</i>^<i>+/+</i> mice.

<p>H&E staining of pancreatic tissues from <i>Pdx1-Cre</i>;<i>LSL</i>-<i>Kras</i>^{<i>G12D/</i>+}<i>;Trp53</i>^{<i>flox/wt</i>}<i>;Ksr1</i>^<i>+/+</i>, <i>Ksr1</i>^{<i>+/ -</i>}, and <i>Ksr1</i>^<i>-/-</i> mice sacrificed at 3 months of age highlights PanIN lesions surrounded by normal tissue (bar = 40μm).</p

<i>Pdx1-Cre;LSL-Kras</i>^{<i>G12D/+</i>}<i>;Trp53</i>^{<i>flox/wt</i>}<i>;Ksr1</i>^<i>-/-</i> mice develop pancreatic tumors.

<p>H&E (top), pERK (middle) and Ki67 (bottom) staining of tumors harvested from <i>Pdx1-Cre</i>;<i>LSL</i>-<i>Kras</i>^{<i>G12D/</i>+}<i>;Trp53</i>^{<i>flox/wt</i>}<i>;Ksr1</i>^<i>+/+</i>, <i>Ksr1</i>^<i>+/-</i>, and <i>Ksr1</i>^<i>-/-</i> mice (bar = 100μm). Panels to the right show magnification of indicated region (bar = 40μm). Tumors have moderately differentiated ductal morphology that stains strongly for pERK, accompanied by stromal desmoplasia. Ki67 stains some ductal and surrounding cells.</p

<i>Pdx1-Cre</i>;<i>LSL</i>-<i>Kras</i>^{<i>G12D/</i>+}<i>;Trp53</i>^{<i>flox/wt</i>}<i>;Ksr1</i>^<i>-/-</i> mice have a modest but statistically significant decrease in all-cause morbidity.

<p>A. Kaplan-Meier curves for <i>Pdx1-Cre</i>;<i>LSL</i>-<i>Kras</i>^{<i>G12D/</i>+}<i>;Trp53</i>^{<i>flox/wt</i>}<i>;Ksr1</i>^<i>+/+</i> and <i>Ksr1</i>^<i>+/-</i> mice based on age at sacrifice or death. 8 <i>Ksr1</i>^<i>+/-</i> and 10 <i>Ksr1</i>^<i>+/+</i> mice had to be censored. Median age at sacrifice or death was 152 days for <i>Ksr1</i>^<i>+/-</i> mice and 160 days for <i>Ksr1</i>^<i>+/+</i>mice; there was no statistically significant difference between the two groups (p = 0.4683 by log-rank test). B. Kaplan-Meier curves for <i>Pdx1-Cre</i>;<i>LSL</i>-<i>Kras</i>^{<i>G12D/</i>+}<i>;Trp53</i>^{<i>flox/wt</i>}<i>;Ksr1</i>^<i>-/-</i>, and <i>Ksr1</i>^<i>+/-</i> combined with <i>Ksr1</i>^<i>+/+</i> mice based on age at sacrifice or death. 3 <i>Ksr1</i>^<i>-/-</i> were censored. There was a modest but statistically significant difference between median age at sacrifice or death for <i>Ksr1</i>^<i>-/-</i> mice and the control group (191 and 159 days, p = 0.0344 by log-rank test).</p