TPP A tumor-cell specific Hsp70 peptide-based probe for selective in vivo tumor targeting (EP-patent application pending (filed: 06/2014))

Transcription

1 TPP A tumor-cell specific Hsp70 peptide-based probe for selective in vivo tumor targeting (EP-patent application pending (filed: 06/2014)) Stefan Stangl, Gabriele Multhoff Department of Radiation Oncology, Klinikum rechts der Isar, TU Munich

2 Heat shock protein 70 physiology C-terminus (aa ) gene: chromosome 6p (TNFα - Hsp70 - complement) N-ATPase domain (aa ) protein: 641aa, 72 kda, cytosolic protein, gobular, no transmembrane domain, stress-inducible (e.g. temperature, radiation, toxins), highly conserved domains: ATPase (44kDa), substrate binding and oligomerization (18kDa), C-terminal helix (10kDa) Substrate-binding domain (aa ) function: molecular chaperone (protection, (re)folding, transport,..), danger signal (inflammation, tumor)

3 Hsp70 in tumor cells membrane Hsp70 targeting cytoplasm carcinogenesis cmhsp70.1mab TPP Vega et al., J Immunol 2008 Gehrmann et al., PLOS One 2008 Pfister et al. Cancer 2007 Hantschel et al., Cell Stress Chaperones 2000 Multhoff et al., Int J Cancer 1995 Hsp70 specific tumor cell penetrating peptide

4 Hsp70 is a negative prognostic marker Overall Survival (%) 100 Hsp70 membrane expression and overall survival (NSCLC) Squamous cell carcinoma Hsp70- Hsp70+ n = 19 p < 0.05 Months after Surgery Hsp70 membrane expression correlates with decreased OS Liver carcinoma (Gehrmann Front. Immunol. 2014) AML, ALL, MDS (Yeh LR 2010) Lung squamous cell carcinoma (Pfister Cancer 2007) H&N squamous cell carcinoma (Gehrmann Radiat. Onkol. 2014) Lower rectal carcinoma (Pfister Cancer 2007) Colon carcinoma (Kocsis CSC 2010) Sarcoma (unpublished) Glioblastoma (unpublished)

5 Experimental setup in vivo imaging probes: TPP, cmhsp70.1, Integrisense (sm a V b 3 integrin antagonist) tumors: colon (4), breast (4), pancreas (4), lung (2), head&neck (2), cervix (1) tumor model bispectral nir in vivo imaging tumor digestion ex vivo cytometry viable tissue cells tumor (CD45 - /CD140b - ) tumor-infiltrating MΦ (CD45 + / F4/80 + ) intrinsic fluorescence microscopy tumor-associated fibroblasts (CD45 - /CD140b + )

6 Epitope presence (membrane Hsp70, Integrin a v b 3, ex vivo) fibrotic (normal) cells tumor-associated Fibroblasts TPP CD61 tumor infiltrating MΦ TPP CD61 various tumor entities are membrane Hsp70 positive (but not normal fibrotic cells) Stangl et al., Cancer Res 2014

7 In vivo imaging: cmhsp70.1, TPP (4T1 o.t., metastasizing) tumorspecific enrichment of cmhsp70.1 and TPP reach maxima after 24h Stangl et al., Radiother Oncol 2011, Cancer Res 2014

8 % id/g Klinik und Poliklinik für Strahlentherapie und Radiologische Onkologie In vivo biodistribution: TPP, cmhsp70.1 (CT26 s.c.) TPP (nir fluorescence) cmhsp Zr (PET) TPP shows specific enrichment at the tumor, unbound TPP is cleared out of the body rapidly through renal pathway cmhsp70.1 shows high enrichment at the tumor, biodistribution is characteristic for antibodies Stangl et al., Cancer Res 2014

9 In vivo imaging: TPP, Integrisense (colitis associated carcinoma) color TPP[680] IS[750] binding of TPP is tumorcell specific Stangl et al., Cancer Res 2014

10 In vivo imaging: TPP, Integrisense (human tumor cell lines) tumorspecific in vivo enrichment of TPP in human xenograft models is improved, compared to IS Stangl et al., Cancer Res 2014

11 Scientific summary Hsp70 is a universal tumor specific biomarker TPP peptide stains tumor cells but not corresponding normal tissues TPP is a highly tumor-specific tool for in vivo tumor imaging TPP accumulates within the tumor at high quantities TPP shows superior biodistribution compared to Antibody-based compounds Hsp70-targeted in vivo tumor targeting results in more specific tumor enrichment, compared to integrin a V b 3 -specific targeting

12 Business related informatin Hsp70 is an universal Tumorspecific biomarker with rapid turnover rates capabilities as diagnostic compound for many tumor entities highly precise enrichment at high quantities higher specificity, compared to comm. available compounds potential for tumor targeted prognostic and therapeutic agents TPP is a non-immunogeneic, natural occuring, small molecule peptide easy translation into the clinics low production costs favourable biodistribution Market potential: approx mio $ Development status: preclinically evaluated at 6 tumor types (17 different tumors) EP-patent application pending (filed: 06/2014)

13 Department of Radiotherapy and Radiation Oncology Klinik und Poliklinik für Strahlentherapie und Radiologische Onkologie Acknowledgements Scientific team PI: Prof. Dr. Gabriele Multhoff Stefan Stangl Mathias Gehrmann Janina Erl Jessica Pelzel Thomas Schmid Wolfgang Sievert Cooperations Prof. Dr. Vasilis Ntziachristos (TUM, HelmholtzZentrum Munich) Prof. Dr. Florian Greten (TUM, MRI, Georg-Speyer-Haus, Frankfurt a.m.) Prof. Dr. Jens Siveke (TUM, MRI) Prof. Dr. Johannes Buchner (TUM) Contact Prof. Dr. G. Multhoff Dr. Sarah Krüger: Funding DFG: SFB 824 BMBF: MOBITUM HelmholtzZentrum München, TU-München Thank you for your attention!