2-Deoxyglucose and Retinoic Acid as Potential Adjuvants in Combination with Molecularly Targeted Radiotherapy in Neuroblastoma

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1 2-Deoxyglucose and Retinoic Acid as Potential Adjuvants in Combination with Molecularly Targeted Radiotherapy in Neuroblastoma Cancer Health Disparities Summit 2008 Cancer Therapeutics and Radiopharmaceutical Research Session July 15, 2008

2 The Disease Neuroblastoma A solid tumor derived from neural crest Accounts for ~15% of cancer deaths in kids Occurs in children from birth to age 10 yrs Most common pediatric extracranial tumor Frequently metastatic at the time of diagnosis Only 34% 3-year event-free survival for high risk neuroblastoma

3 New Therapeutic Modalities Molecularly Targeted Radiotherapy Receptor ligands or antibodies coupled to a therapeutic radionuclide 2-Deoxyglucose Glucose analog that induces metabolic oxidative stress Retinoic Acid Differentiation agent, slows cell division

4 Standard of Care for High-Risk NB 1) High-dose combination chemotherapy 2) Tumor resection after response 3) Myeloablative chemotherapy followed by autologous bone marrow transplant 4) Radiation to the primary tumor site 5) After recovery, oral 13-cis retinoic acid for 6-12 months From NCI PDQ information on neuroblastoma

5 Advantages of Molecularly Targeted Radiotherapy and Peptide-based Tumor Imaging Radiopeptide ligand can be tailored to target tumor receptor (expression determined by biopsy); can spare normal tissue more than external beam radiation or chemotherapy Disseminated tumor metastases can still be effectively targeted; impractical for external beam radiation Imaging / dosimetry and therapy can be performed with the same basic compound (e.g. 111 In-octreotide and 90 Y- octreotide) Tumor does not have to be glucophilic (as for 18 FDG-PET) and is suitable for intracranial imaging

6 I cell neural crest stem cell?? NGF VPAC1 (RA?) N cell bcl-2, RAR, sst-1/2 IGF1R, VPAC1 VIP RA? S cell ttg, RAR, VPAC1 D. Balster Ph.D. dissertation

7 Switching of Cell Morphology in a Clonal SK-N-SH Population N cells S cells I cells

8 Percent of Surviving Clones SK-N-SH Clonal Survival Morphology after 2-Deoxyglucose Treatment 0 small (I) med or mix (N) large (S) 0x 1x 2x 0x 1x 2x 0x 1x 2x 24 hrs 48 hrs 72 hrs Treatment / Time N cells appear to be more resistant to 2-DG

9 2-Deoxyglucose Treatment of SK-N-SH Neuroblastoma Percent Clonal Survival hr 48hr 72hr 0 Control 1x (5.5mM) 2x (11mM) 2-DG Treatment

10 140 SH-SY5Y Oxidative Metabolic Stress Percent Survival Control 2-DG NAC Ret Ac. PEG- SOD&PEG- CAT Treatment (24 hr) 2DG+NAC 2DG+Ret Ac. 2DG+PEG- SOD&PEG- CAT

11 Combining 2-Deoxyglucose with Yttrium-90 Octreotide SHSY5Y SKNSH Surviving Fraction Control 2DG 2DG,90Y 2DG+90Y 90Y Treatment

12 control TtG 13-cis RA SK-N-SH treated with 13-cis Retinoic Acid control sst2 bcl-2 DAPI 13-cis RA

13 Differentiation of N-type Neuroblastoma Cells to more S-type In Vitro Red = bcl-2; Green = Transglutaminase 2; Blue = DAPI SH-SY-5Y treated once with 20μM 13-cis retinoic acid and grown for 4 days (a sub-line of SK-N-SH of the N type)

14 Conclusions The 3 neuroblastoma cell phenotypes (N, S, and I) can have different drug sensitivities (13-cis) Retinoic acid can induce maturation and upregulation of somatostatin receptor 2-DG and 90 Y-Octreotide are more effective when given simultaneously If retinoic acid priming does allow for greater tumor uptake of somatostatin-receptor targeted radiotherapy, and / or induces greater sensitivity to metabolic oxidative stress with 2-deoxyglucose, it may be a useful addition to neuroblastoma therapy using 90 Y-Octreotide.

15 Future Directions Finish ongoing in vitro studies 1) further determine 2-DG sensitivity of N vs S vs I 2) quantitation of sst2 up-regulation Proof of concept(s) in vivo using xenograft 1) the RA upregulation (using P.E.T.) (rat) 2) the combination of 2-DG and RA (mice) 3) the combination of RA, 2-DG, and 90 Y- Octreotide (or other SST analog)

16 Acknowledgements My mentors, Prof. M.S. O Dorisio and Prof. D.R. Spitz Dr. D. A. Balster s dissertation Analysis of Heterogeneous Populations of Neuroblastoma Cells. Ohio State, 1999 J. Biedler of the Memorial Sloan-Kettering, who founded and characterized SK-N-SH NIH and NCI for their program Supplements to Promote Reentry into Biomedical and Behavioral Research Careers Supplemental grant 3R01CA S1 to Metabolic Oxidative Stress in Human Cancer Cells Douglas R. Spitz, P.I.