Cancer-targeted IL-12 controls human rhabdomyosarcoma by senescence induction and myogenic differentiation

Abstract

Stimulating the immune system to attack cancer is a promising approach, even for the control of advanced cancers. Several cytokines that promote interferon-γ-dominated immune responses show antitumor activity, with interleukin 12 (IL-12) being of major importance. Here, we used an antibody-IL-12 fusion protein (NHS-IL12) that binds histones of necrotic cells to treat human sarcoma in humanized mice. Following sarcoma engraftment, NHS-IL12 therapy was combined with either engineered IL-7 (FcIL-7) or IL-2 (IL-2MAB602) for continuous cytokine bioavailability. NHS-IL12 strongly induced innate and adaptive antitumor immunity when combined with IL-7 or IL-2. NHS-IL12 therapy significantly improved survival of sarcoma-bearing mice and caused long-term remissions when combined with IL-2. NHS-IL12 induced pronounced cancer cell senescence, as documented by strong expression of senescence-associated p16INK4a and nuclear translocation of p-HP1γ, and permanent arrest of cancer cell proliferation. In addition, this cancer immunotherapy initiated the induction of myogenic differentiation, further promoting the hypothesis that efficient antitumor immunity includes mechanisms different from cytotoxicity for efficient cancer control in vivo.

Nuclear Translocation of Argonaute 2 in Cytokine-Induced Senescence

“…CIS is now accepted as a non-cell-autonomous inducer of cellular senescence that limits tumorigenesis [15], and several different cytokines or cytokine mixtures, e.g. interleukin-6 (IL-6) [39], transforming growth factor beta (TGF-β) [40], or IFN-γ and TNF [12][13][14], have been implicated in senescence induction. …”

“…2E). Further experiments using the cytokine-sensitive rhabdomyosarcoma cell line A204 [12,13] demonstrated that IFN-γ + TNF also induced the flat senescence-associated morphology (Fig. 2F), increased SA-β-gal activity (Fig.…”

“…The combined action of interferon-γ (IFN-γ) and tumor necrosis factor (TNF) drives various cancer cells into senescence [12][13][14]. We therefore treated MCF-7 cells with the established cytokine cocktail for 96 h, and then analyzed different senescence-associated markers.…”

“…Recently, we and others described cytokine-induced senescence (CIS) as an extrinsic form of senescence. In these studies, adoptive transfer of T helper 1 (T H 1) cells [12] or the application of T H 1 cell cytokines IFN-γ and TNF [12][13][14] permanently growth-arrested different cancer cells and induced various senescence markers in vitro and in vivo. Thus, CIS can be considered to be a part of the bodies´ immune surveillance machinery [15] playing an important role in the equilibrium phase [16] of cancer development.…”

Enhanced binding of necrosis-targeting immunocytokine NHS-IL12 after local tumour irradiation in murine xenograft models

“…When combined with irradiation, the immunocytokine showed significant growth delay in a Lewis lung carcinoma model [15]. In humanized mice, the human NHS-IL12 construct also used in this study led to tumour control via Th1-polarized immune responses leading to cancer senescence and differentiation [16].…”