Article Text

Download PDFPDF

Local immunotherapy with ONCOS-102 shapes harmful tumor associated CD68+ macrophages to become beneficial cells that correlate with increased overall survival
Free
  1. Sari Pesonen1,
  2. Johan Lundin2,
  3. Nina Linder2,
  4. Riku Turkki2,
  5. Ari Ristimäki3,
  6. Timo Joensuu4,
  7. Kalevi Kairemo4,
  8. Kaarina Partanen4,
  9. Tuomo Alanko4,
  10. Elke Jäger5,
  11. Julia Karbach5,
  12. Claudia Wahle5,
  13. Akseli Hemminki6,
  14. Charlotta Backman1,
  15. Mikael von Euler1,
  16. Tiina Hakonen1,
  17. Tuuli Ranki1,
  18. Antti Vuolanto1,
  19. Magnus Jäderberg1 and
  20. Dmitry Zamarin7
  1. Aff1 grid.430088.7Oncos Therapeutics Helsinki Finland
  2. Aff2 grid.452494.a0000000404095350Institute for Molecular Medicine Finland (FIMM) Helsinki Finland
  3. Aff3 grid.15485.3d0000000099505666Division of Pathology, HUSLAB and Hartman InstituteHelsinki University Central Hospital Helsinki Finland
  4. Aff4 Docrates Cancer Center Helsinki Finland
  5. Aff5 grid.468184.70000000404907056Hämatologie-Onkologie, Krankenhaus Nordwest Frankfurt Germany
  6. Aff6 grid.7737.40000000404102071Cancer Gene Therapy Group, Medicum, Haartman InstituteUniversity of Helsinki, and TILT Biotherapeutics Ltd Helsinki Finland
  7. Aff7 grid.51462.340000000121719952Memorial Sloan Kettering Cancer Center New York NY USA

Statistics from Altmetric.com

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

Meeting abstracts

With the increasing excitement around new immunotherapeutic approaches, there has been a shift in the way viral cancer therapy is regarded from providing mainly oncolysis towards being a cancer immunotherapy. Adenoviruses have a unique ability to prime and boost immune responses. GM-CSF coding adenovirus ONCOS-102 causes immunogenic cancer cell death whereupon tumor antigens are presented into the immunogenic environment. ONCOS-102 has been previously shown to initiate CD8+ T cell responses against tumor-derived antigens in chemotherapy refractory cancer patients.

A total of 12 cancer patients were treated with repeated intratumoral injections of ONCOS-102 in a Phase I study. Sequential biopsies were collected at baseline and 1 and 2 months after treatment initiation and analyzed for the presence of immune cells by immunohistochemistry (IHC) in digitally scanned samples. Readout of the expression levels for innate immune cells (CD68, CD163, CD11c), T cells (CD3, CD4, CD8), and B cells (CD19) was performed in tumorous regions by the use of an image analysis algorithm based on color deconvolution and segmentation of the IHC stained cells. In an exploratory analysis, correlation between absolute expression levels of different immune cell markers in tumors and overall survival (OS) was assessed by Spearman´s rank correlation analysis.

At baseline, the absolute expression level of macrophage marker CD68 negatively correlated with OS (correlation coefficient (r)= -0.59, p=0.04), suggesting that tumor-associated macrophages (TAMs) in untreated tumors were tumorigenic. No correlation between other immune cell markers and OS was seen at baseline. 11/12 patients showed a post-treatment increase in tumor-infiltrating innate and adaptive immune cells, with the most prominent increase seen in CD8+ cells. In contrast to baseline, post-treatment samples showed a positive correlation between the expression level of CD68+ cells and OS (r=0.71, p=0.01), suggesting that CD68+ macrophages that were attracted into tumors after ONCOS-102 injection displayed different functionality than TAMs present prior to treatment. Furthermore, absolute expression levels of T cell markers CD3 (r=0.74, p=0.006), CD4 (r=0.76, p=0.004), and CD8 (r=0.73, p=0.007) in post-treatment biopsies all positively correlated with OS.

To summarize, ONCOS-102 induced infiltration of CD68+ macrophages and T cells which was associated with increased OS, while CD68+ TAMs pre-treatment was associated with shortened OS. This suggest that local immunotherapy with ONCOS-102 has the potential to activate immunologically silent tumors and reduce local immune suppression in advanced tumors.