Co-targeting of the PI3K/AKT/mTOR and RAS/RAF/MEK/ERK Pathways as a Strategy for Cancer Treatment. Joseph Valentino, M.D. 11/30/11

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1 Co-targeting of the PI3K/AKT/mTOR and RAS/RAF/MEK/ERK Pathways as a Strategy for Cancer Treatment Joseph Valentino, M.D. 11/3/11

2 Molecular Targeted Cancer Therapy Limitations of traditional chemotherapy Increasing awareness of specifically mutated pathways in cancer Efforts to develop drugs that specifically target abnormal pathways

3 PI3K/Akt/mTOR & RAS/RAF/MEK/ERK Signaling Pathways RTK PIP3 AKT IRS Ras PI3-K PIP2 PTEN PHLPP PDK1 mtorc2 Raf P AKT P MEK mtorc1 ERK 4E-BP1 p7s6k

4 Co-targeting of the PI3K and RAS Pathways for the Treatment of Carcinoid Tumors

5 Increasing Incidence of Carcinoid Yao, et al. J Clin Oncol. 28 Jun 2;26(18):

6 Carcinoid Syndrome and Fibrosis

7 Experimental Design Purpose: Understanding the role of PI3K/AKT/mTOR and RAS/RAF/MEK/ERK pathways incarcinoid disease. 1) Assess the frequency of PI3K and RAS mutations 2) Determine the effects of inhibition of these pathways on cell proliferation, apoptosis, and secretion 3) Evaluate the effects of combined inhibition of both of these pathways

8 The BON cell line a model of carcinoid tumors CgA CgA NT NT

9 Mutational Analysis Cell line Source PIK3CA KRAS NRAS BON Human pancreatic carcinoid E545A WT Q61R QGP-1 Human pancreatic somatostatinoma E545A G12V WT NCI-H727 Human lung carcinoid E545A G12V WT UMC-11 Human lung carcinoid WT WT WT

10 PI3K Inhibition Results in Anti-neoplastic Effects BKM12 BEZ Apoptosis (BON) NTC 1uM 2.5uM 5uM NTC 1nM 1nM 1nM BKM12 BEZ235 Cell Viability DMSO Control 1nM 1nM 1nM BON.6 UMC-11.4 NCI-H727.2 QGP-1 DMSO Control 1nM 1nM 1nM BON UMC-11 NCI-H727 QGP-1

11 Final Tumor Volume and Weight of Mice Treated with Orally Administered BEZ235 x 25 days BEZ235 - Average Tumor Volume BEZ235 - Average Tumor Weight Volume (mm^3) 15 1 Weight (grams) Vehicle Control BEZ235 Vehicle Control BEZ235 Vehicle Control Treatment

12 PI3K Inhibition Increases Signaling through the RAS/RAF/MEK/ERK Pathway BKM12 BEZ235 C uM C 1 1 1nM IRS PI3-K perk ERK Β-actin Ras Raf MEK ERK

13 Combined PI3K and MEK Inhibition Decreases Cell Proliferation Cell Count (x1^6) BON cells treated with BKM12, PD91, or combination x 72h Cell Count (x1^6) BON cells treated with BEZ235, PD91, or combination x 72h DMSO Control BKM12 PD91 BKM12/PD91 DMSO Control BEZ235 PD91 BEZ235/PD DNA fragmentation Abs (45-49) nm DNA fragmentation Abs (45-49) nm DMSO Control BKM12 PD91 BKM12/PD91 Treatment DMSO Control BEZ235 PD91 BEZ235/PD91 Treatment

14 Co-treatment with a MEK Inhibitor Blocks the Increase in Secretion that Occurs with PI3K Inhibition BON QGP * NT (pg/ml) * * PIK-75 (.5 μm) PD9859 (1 μm)

15 Conclusions Mutations of the PI3K and RAS pathway are common in neuroendocrine cell lines PI3K inhibition Effective as individual therapy Upregulation of RAS/RAF/MEK/ERK Increased Secretion PI3K inhibition combined with MEK inhibition Enhanced effects Blocks increase in secretion

16 Novel sirna Co-targeting Strategy as Treatment for Colorectal Cancer

17 Discovery of sirna Discovered in 1998 in nematodes nucleotide segments of RNA Very specific, wide variety of targets

18 Experimental Design Purpose: Comparative analysis of a panel of sirna directed toward specific components of either the PI3K or RAS pathways Cell Lines - Likely effected by mutational profile HCT 116 and DLD-1 Outcomes proliferation, apoptosis

19 sirna Knockdown of Selected Targets PI3K/Akt/mTOR Pathway RAS/RAF/MEK/ERK Pathway.6.6 HCT116 Cell Viability (x1^6) Cell Viability (x1^6) NTC p85a p11a Akt1 Akt2 Rictor Raptor NTC KRAS BRAF MEK1 MEK2 ERK1 ERK DLD-1 Cell Viability (x1^6) Cell Viability (x1^6) NTC p85a p11a Akt1 Akt2 Rictor Raptor NTC KRAS BRAF MEK1 MEK2 ERK1 ERK2

20 Cell Count (x1^6) Combined PI3K and RAS sirna Targeting Cell Viability Apoptosis HCT116 HCT NTC p11a KRAS p11a/kras Cell Count (x1^6) DLD-1 NTC p11a KRAS p11a/kras p11a sirna Akt2 sirna KRAS sirna p11α Akt2 KRAS p4ebp1 Total 4eBP

21 Conclusions P11α and KRAS are the most effective sirna treatments in their individual pathways Combination treatments are more effective than single agents 4E-BP1, a downstream effector common to both pathways, may serve as a marker of effective treatment

22 Liver Directed sirna Therapy in the Treatment of Colon Cancer

23 Barriers to sirna delivery sirna instability Enzymatic degradation Rapid renal clearance

24 Organ Directed Therapy Concentrated delivery to target organ Feasible in humans No animal models

25 Experimental Design Purpose: Develop a mouse model of portal vein catheterization for the chronic delivery of therapeutic agents to liver metastases

26 Portal Vein Catheter Video

27 Catheter Placement and Portal Vein Distribution

28 Delivery of DY-547 Labeled sirna to Liver Metastases

29 Conclusions Portal vein catheterization is technically feasible Liver directed therapy results in enhanced uptake of sirna as confirmed by IVIS imaging sirna is able to be delivered to metastatic disease using this technique