RESUMO
This corrects the article DOI: 10.1038/ncomms14278.
RESUMO
Small-molecule inhibitor of apoptosis (IAP) antagonists, called Smac mimetic compounds (SMCs), sensitize tumours to TNF-α-induced killing while simultaneously blocking TNF-α growth-promoting activities. SMCs also regulate several immunomodulatory properties within immune cells. We report that SMCs synergize with innate immune stimulants and immune checkpoint inhibitor biologics to produce durable cures in mouse models of glioblastoma in which single agent therapy is ineffective. The complementation of activities between these classes of therapeutics is dependent on cytotoxic T-cell activity and is associated with a reduction in immunosuppressive T-cells. Notably, the synergistic effect is dependent on type I IFN and TNF-α signalling. Furthermore, our results implicate an important role for TNF-α-producing cytotoxic T-cells in mediating the anti-cancer effects of immune checkpoint inhibitors when combined with SMCs. Overall, this combinatorial approach could be highly effective in clinical application as it allows for cooperative and complimentary mechanisms in the immune cell-mediated death of cancer cells.
Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Interferon-alfa/imunologia , Interferon beta/imunologia , Tiazóis/farmacologia , Imunidade Adaptativa/efeitos dos fármacos , Animais , Antineoplásicos/síntese química , Antígeno B7-H1/genética , Antígeno B7-H1/imunologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/mortalidade , Linhagem Celular Tumoral , Feminino , Regulação da Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/imunologia , Glioblastoma/genética , Glioblastoma/imunologia , Glioblastoma/mortalidade , Humanos , Imunidade Inata/efeitos dos fármacos , Memória Imunológica , Proteínas Inibidoras de Apoptose/genética , Proteínas Inibidoras de Apoptose/imunologia , Interferon-alfa/genética , Interferon-alfa/farmacologia , Interferon beta/genética , Interferon beta/farmacologia , Camundongos , Poli I-C/farmacologia , Transdução de Sinais , Análise de Sobrevida , Linfócitos T Citotóxicos/efeitos dos fármacos , Linfócitos T Citotóxicos/imunologia , Tiazóis/síntese química , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/farmacologia , Vesiculovirus/genética , Vesiculovirus/imunologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Rhabdomyosarcoma (RMS), a neoplasm characterized by undifferentiated myoblasts, is the most common soft tissue tumour in children. Therapeutic resistance is common in RMS and is often caused by acquired defects in the cellular apoptotic program. Smac mimetic compounds (SMCs) are a novel class of inhibitor of apoptosis (IAP) antagonists that are currently under clinical development as cancer therapeutics. We previously reported that cIAP1 is overexpressed in human primary RMS tumours and in patient-derived RMS cell lines where it drives resistance to apoptosis. In this study, we investigated whether inflammatory cytokine production triggered by activators of innate immunity synergizes with LCL161 to induce bystander killing of RMS cells in vitro and in vivo. Indeed, we show that innate immune stimuli (oncolytic virus (VSVΔ51-GFP), interferon γ (IFNγ), and tumour necrosis factor-like weak inducer of apoptosis (TWEAK)) combine with SMCs in vitro to reduce cell viability in the Kym-1 RMS cancer cell line. Other human RMS cell lines (RH36, RH41, RD, RH18, RH28, and RH30) and the murine RMS cell line 76-9 are resistant to treatment with LCL161 alone or in combination with immune stimulants in in vitro cell viability assays. In contrast, we report that the combination of LCL161 and VSVΔ51-GFP reduces tumour volume and prolongs survival in a 76-9 syngeneic murine model. Our results support further exploration of the combined use of IAP antagonists and innate immune stimuli as a therapeutic approach for RMS cancers.