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Title: REVISITING INTERLEUKIN-12 AS A CANCER IMMUNOTHERAPY
AGENT
Authors: Pedro Berraondo1,2,3*
, Iñaki Etxeberria1,2
, Mariano Ponz-Sarvise2,4
, Ignacio
Melero1,2,3,4
1 Immunology and Immunotherapy Program, Center for Applied Medical Research,
CIMA, University of Navarra, Pamplona, Spain.
2 Navarra Institute for Health Research (IDISNA), Pamplona, Spain.
3 Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), Spain.
4 Departments of Oncology and immunology, University Clinic of Navarra, Pamplona,
Spain.
Correspondence:
Ignacio Melero MD PhD.
CIMA and CUN
Av Pio XII,55
31008 Pamplona. Spain
Running title: IL-12 back to the future
Conflicts of interest: IM is a consultant for Bristol-MyersSquibb, Roche-Genentech
Bayer, Medimmune, Merck Serono, Genmab, F-Star, TUSK, Alligator, Bioncotech and
receives research grants from Roche Genentech, Bristol Myers Squibb and Alligator.
Financial support: I. Melero is supported by MINECO (SAF2014-52361-R and
SAF2017-83267-C2-1R), European Commission VII Framework and Horizon 2020
programs (IACT and PROCROP), Cancer Research Institute (CRI) CLIP Grant 2017,
Fundación de la Asociación Española Contra el Cáncer (AECC) and Fundación BBVA.
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ABSTRACT
Interleukin-12 antitumor activities are mediated by the activation of T and NK
lymphocytes to produce IFNγ. Systemically, recombinant interleukin-12 has a narrow
therapeutic window that favors local delivery, i.e., by gene therapy approaches.
Interleukin-12 is a powerful partner in immunotherapy combinations with checkpoint
inhibitors and adoptive T-cell transfer.
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TEXT
In this issue of Clinical Cancer Research, Hu et al. report on the plasmid gene transfer
of an interleukin-12 (IL-12) gene expression cassette to mouse transplantable tumors
and to xenografted human tumors in NSG mice (1). IL-12 local expression is attained
by injecting plasmid DNA and performing in vivo electroporation inserting a needle-
shaped electrode (1). This strategy is currently under clinical trials as a single agent
(NCT01579318, NCT00323206, NCT01502293, and NCT02345330) and in
combination with pembrolizumab (NTC02493361 and NTC03132675). In these mice,
IL-12 is combined with doxorubicin, a chemotherapy agent with multiple effects on the
tumor tissue microenvironment that can help the antitumor immune response such as
immunogenic cell death of a fraction of tumor cells (2) and reduction of T regulatory
cells and myeloid-derived suppressor cells (3,4). Indeed, under treatment, tumors
accumulated infiltrating cytotoxic T cells (CD8+ NKG2D
+). If exogenous T cells
recognizing tumor antigens are infused, these adoptively transferred cells extravasate
and infiltrate the tumor much more efficiently.
Adoptive T cell therapy is revolutionizing cancer therapy mainly for hematological
malignancies. Chimeric antigen receptor-transduced T cells, tumor-infiltrating
lymphocytes (TILs), and T cell receptor-transduced cells are in the limelight of clinical
development. Early observations suggested that IL-12 local gene therapy can be
synergistically combined with adoptive T cell transfer (5). Moreover, attempts to
engineer T cells to produce IL-12 in a controlled fashion have been shown to be
remarkably efficacious in pre-clinical models, although toxic due to leaky expression of
the retroviral construct (6). Therefore, safer modes of conferring T cells the ability to
produce IL-12 in an autocrine fashion are needed.
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A remarkable function of IL-12 is its ability to induce IFNγ release from NK cells as
well as CD4+ and CD8
+ T cells. In fact, IL-12 signaling via STAT-4 is critical for Th1
differentiation and acquisition of cytolytic functions by CD8+ T cells (7). IFNγ in turn
strongly modifies the tumor microenvironment. The best studied beneficial mechanisms
are (Figure 1):
(i) Enhancing major histocompatibility class I antigen presentation in tumor cells.
(ii) Inducing the expression of CXCL9, 10 and 11 chemokines to attract NK, Th1
and CD8+ T cells.
(iii) Transforming M2 macrophages into activated antitumor M1 macrophages.
(iv) Acting on endothelial cells to mediate anti-angiogenesis in a CXCR3-dependent
fashion, while enhancing the expression of homing receptors for T cell
recruitment.
Unfortunately, IFNγ is also the main mediator of the toxic effects of IL-12 and over
time turns on immunoregulatory mechanisms such as PD-L1 and IDO-1 expression
which mediate adaptive resistance to immunotherapy.
In the era of checkpoint inhibitors and adoptive T cell therapy, we must revisit IL-12 as
an antitumor agent. On the one hand, IL-12 can be synergistic with PD-1/PD-L1
blockade (8) and on the other hand, it might help T cell therapy in several ways,
adoptive chiefly by including attraction and homing to the tumor tissue as reported by
Hu et al. in mouse models (1). The foreseen importance of these mechanisms is that IL-
12 might be a key tool to translate the efficacy of adoptive T cell therapy to a wider
spectrum of tumors aside from B cell malignancies, melanoma, and synovial sarcoma.
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IL-12 is neglected to some extent in clinical development with some exceptions: Merck
Serono is testing a fusion protein encompassing single chain IL-12 coupled to an
antibody that binds extracellular dsDNA (9). There are also attempts by Moderna
Therapeutics/MedImmune to transfer mRNA encoding IL-12 as well as the intratumoral
gene-electroporation strategies by OncoSec Medical (NTC03132675) already
commented on.
It must be said that IL-12 is a powerful wild horse difficult to harness (10). Systemic
treatment has a narrow therapeutic window due to circulating IFNγ levels that can be
fatal. Permanent retroviral gene-transfer of IL-12 into T cells has serious safety
problems (11). The route to clinical success of IL-12-based immunotherapy must
contemplate three key concepts:
i) Transient exposure or expression.
ii) Combination with other agents chiefly including adoptive T cell therapy and
checkpoint inhibitors.
iii) If possible, targeting the cytokine or its function or its expression to the tumor
microenvironment.
The potential of IL-12 as a partner in combination immunotherapy strategies is
promising and in need of improvements based on biotechnology, gene therapy and cell
therapy. The promotion of T-cell infiltration into tumors by IL-12 is certainly an
exciting feature. IL-12 is “back to the future.”
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REFERENCES
1. Hu J, Sun C, Bernatchez C, Xia X, Hwu P, Dotti G, et al. T cell homing therapy
for reducing regulatory T cells and preserving effector T cell function in large
solid tumors. Clinical cancer research : an official journal of the American
Association for Cancer Research 2018 doi 10.1158/1078-0432.CCR-17-1365.
2. Casares N, Pequignot MO, Tesniere A, Ghiringhelli F, Roux S, Chaput N, et al.
Caspase-dependent immunogenicity of doxorubicin-induced tumor cell death.
The Journal of experimental medicine 2005;202(12):1691-701 doi
10.1084/jem.20050915.
3. Hsu FT, Chen TC, Chuang HY, Chang YF, Hwang JJ. Enhancement of adoptive
T cell transfer with single low dose pretreatment of doxorubicin or paclitaxel in
mice. Oncotarget 2015;6(42):44134-50 doi 10.18632/oncotarget.6628.
4. Alizadeh D, Trad M, Hanke NT, Larmonier CB, Janikashvili N, Bonnotte B, et
al. Doxorubicin eliminates myeloid-derived suppressor cells and enhances the
efficacy of adoptive T-cell transfer in breast cancer. Cancer research
2014;74(1):104-18 doi 10.1158/0008-5472.CAN-13-1545.
5. Mazzolini G, Qian C, Narvaiza I, Barajas M, Borras-Cuesta F, Xie X, et al.
Adenoviral gene transfer of interleukin 12 into tumors synergizes with adoptive
T cell therapy both at the induction and effector level. Human gene therapy
2000;11(1):113-25 doi 10.1089/10430340050016201.
6. Kerkar SP, Muranski P, Kaiser A, Boni A, Sanchez-Perez L, Yu Z, et al. Tumor-
specific CD8+ T cells expressing interleukin-12 eradicate established cancers in
Cancer Research. on November 11, 2020. © 2018 American Association forclincancerres.aacrjournals.org Downloaded from
Author manuscripts have been peer reviewed and accepted for publication but have not yet been edited. Author Manuscript Published OnlineFirst on March 16, 2018; DOI: 10.1158/1078-0432.CCR-18-0381
7
lymphodepleted hosts. Cancer research 2010;70(17):6725-34 doi 10.1158/0008-
5472.CAN-10-0735.
7. Carter LL, Murphy KM. Lineage-specific requirement for signal transducer and
activator of transcription (Stat)4 in interferon gamma production from CD4(+)
versus CD8(+) T cells. The Journal of experimental medicine 1999;189(8):1355-
60.
8. Quetglas JI, Labiano S, Aznar MA, Bolanos E, Azpilikueta A, Rodriguez I, et al.
Virotherapy with a Semliki Forest Virus-Based Vector Encoding IL12
Synergizes with PD-1/PD-L1 Blockade. Cancer immunology research
2015;3(5):449-54 doi 10.1158/2326-6066.CIR-14-0216.
9. Fallon JK, Vandeveer AJ, Schlom J, Greiner JW. Enhanced antitumor effects by
combining an IL-12/anti-DNA fusion protein with avelumab, an anti-PD-L1
antibody. Oncotarget 2017;8(13):20558-71 doi 10.18632/oncotarget.16137.
10. Sangro B, Melero I, Qian C, Prieto J. Gene therapy of cancer based on
interleukin 12. Current gene therapy 2005;5(6):573-81.
11. Zhang L, Morgan RA, Beane JD, Zheng Z, Dudley ME, Kassim SH, et al.
Tumor-infiltrating lymphocytes genetically engineered with an inducible gene
encoding interleukin-12 for the immunotherapy of metastatic melanoma.
Clinical cancer research : an official journal of the American Association for
Cancer Research 2015;21(10):2278-88 doi 10.1158/1078-0432.CCR-14-2085.
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FIGURE LEGEND
Figure 1. Mechanisms of action of interleukin 12. Different cells derived from
myeloid precursors release interleukin 12 upon activation. Interleukin 12 induces the
release of interferon gamma by NK cells, CD4+ T lymphocytes, and CD8
+ T
lymphocytes. Interferon gamma is the main mediator of the immunostimulatory
properties of interleukin 12 acting on tumor cells, macrophages, lymphocytes and
endothelial cells.
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Figure 1:
© 2018 American Association for Cancer Research
Interleukin-12
NK cells CD4+ T lymphocytes CD8+ T lymphocytes
IFN
Increased MHCIon tumor cells
M2 to M1 macrophagesconversion
CXCL 9, 10, and 11on lymphocytes
Antiangiogenesis andT-cell recruitment
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Published OnlineFirst March 16, 2018.Clin Cancer Res Pedro Berraondo, Inaki Etxeberria, Mariano Ponz-Sarvise, et al. IMMUNOTHERAPY AGENTREVISITING INTERLEUKIN-12 AS A CANCER
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