Molecular analysis of sporadic and neurofibromatosis 1 (NF1)-associated malignant peripheral nerve sheath tumors Mark A. Watson, Arie Perry, and David H. Gutmann Washington University School of Medicine *Supported by funding from the Department of Defense and Washington University/Siteman Cancer Center

MPNST Devastating tumor Poor response to therapy Poor patient survival Patients with neurofibromatosis 1 (NF1) harbor 10% lifetime risk of developing MPNST

NF1 loss seen in 76% MPNST by FISH Neurofibromin loss seen in 9/9 MPNST NF1 inactivation is critical event in MPNST pathogenesis

p16 deletion in MPNSTs J. Neuropath Exp. Neurol., 2002 Tumorp16 deletion p16 HD Schwannoma 0/5 0/5 Plexiform neurofibroma 0/13 0/13 MPNST 16/20 9/20 (75%) (45%) Synovial sarcoma 5/7 0/7 (71%) Fibrosarcoma 5/6 0/6 (83%) Hemangiopericytoma 8/12 0/12 (67%) CEP9 p16

EGFR amplification in MPNSTs J. Neuropath Exp. Neurol., 2002 Tumor EGF-R amplification Schwannoma 0/5 Plexiform neurofibroma 0/13 MPNST 5/19 (26%) Synovial sarcoma 0/7 Fibrosarcoma 0/6 Hemangiopericytoma 0/13 MB DG206 WU33 KL DP Benign Neurofibromas Malignant Peripheral Nerve Sheath Tumors EGF-R DG102 CEP7 EGFR

Gene expression profiling 25 NF1-associated 17 sporadic tumors Genetic signature to distinguish NF1-associated from sporadic? Genetic signature to predict clinical behavior?

SSSSSSSSSsnssSsnsnNnnnNnnnsNNnsNsnnNNnnnNNnNn SIAT9 MGLL GCM1 SGCE SEC14L1 DDX21 Few, if any, gene expression signatures that distinguish between NF1-associated and sporadic MPNSTs

Survival 24 mo. (n=11) LocusLink IDSymbolNameFCP 5068PAPPancreatitis-associated protein MEF2DMADS box transcription enhancer factor 2, polypeptide D CUL4BCullin 4B PPP3CBProtein phosphatase 3, catalytic subunit, beta NAB1NGFI-A binding protein SLC16A4solute carrier family 16, member

Sporadic (n=17) NF1 (n=25) EGFR Expression EGFR(-) EGFR(+)

Group A NCAM, MBP, L1CAM, PLP1, BLBP, GAP43, APO-D, RELN IGF2, FGFR1, MDK, CCNB1, CCNB2, CCNF, Ki67 EGFR(-) “more differentiated phenotype”

Conclusions 1.NF1 loss is observed in both NF1-associated and sporadic MPNST 2.CDKN2A inactivation is frequently observed in MPNST 3.EGFR amplification is observed in one-third MPNST 4.Expression profiling did not identify a molecular fingerprint that distinguishes NF1-associated from sporadic MPNST 5.Expression profiling identified a molecular fingerprint for a subset of more aggressive MPNSTs 6.Expression profiling identified a molecular fingerprint for a subset of MPNST with a more differentiated phenotype 7.Future prospective studies will be required to determine whether these patterns of gene expression predict clinical behavior