Relating Activating K-Ras Mutations to Small Molecule Sensitivity in Non- Small-Cell Lung Cancer Flavian D. Brown Carleton College Class of 2009

Lung Cancer  Leading cause of death from cancer in the world  Over 90% of NSCLC contain mutations in EGFR, BRAF and K-Ras  Discovery of Gefitnib

Ras Signaling Schubbert et al. (2007) Hyperactive Ras in developmental disorders and cancer. Nature Review of Cancer, Vol Oncogenic Mutation ← ← ←

Hypothesis  NSCLC tumors are genetically sensitized due to changes in cellular state secondary to activating K- Ras mutations. - Different drug targets - Oncogene Addiction

Small Molecule Screens + DMSO Control 100nl Pin Transfer Hrs 72Hrs 2-10Hrs cell adherence 24 Hrs

A549: Hits Highlighted Color coding on the images: Red = unbiased commercial compound Forma set Green = bioactives (including kinase inhibiting drugs) Magenta = HDAC biased DOS Blue = commercial kinase biased (CBkinase) Yellow = analyticon purified natural products Black = DMSO control plate Gray = +con dose plate Hits From Primary Screen

Assay Development

Small Molecule Sensitivity

Structural Activity Relationship Aromatic group at the opposite end of structures Carbon spacer can be rigid or flexible Hydroxamic acids attached to a 4 or 5 carbon chain

Future Investigations  Analyze signaling downstream of the activating mutation -Immunofluorescence -Western Blotting  Target Identification - Pull down assay  Correlate phenotypic data with genetic data - SNP copy number

Impact  Genotype specific inhibitors for K-Ras mutants  Paradigm for investigating genotype- phenotype relationships in other malignancies - WGAS for somatic alterations  Molecularly targeted cancer therapeutics.

Acknowledgements Principle Investigator - Stuart L.Schreiber, Ph.D Mentor - Gopal S. Ramachandran, Ph.D Summer Research Program in Genomics - Shawna Young - Lucia Vielma - Maura L. Silverstein - Bruce Birren, Ph.D Collaborators - Jordi Barretina, Ph.D - Damian W. Young, Ph.D Broad Institute Screening - Nicola Tolliday, Ph.D - Josh Bittker, Ph.D - Melanie de Silva - Kate Hartland

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