RESUMO
New opportunities are needed to increase immune checkpoint blockade (ICB) benefit. Whereas the interferon (IFN)γ pathway harbors both ICB resistance factors and therapeutic opportunities, this has not been systematically investigated for IFNγ-independent signaling routes. A genome-wide CRISPR/Cas9 screen to sensitize IFNγ receptor-deficient tumor cells to CD8 T cell elimination uncovered several hits mapping to the tumor necrosis factor (TNF) pathway. Clinically, we show that TNF antitumor activity is only limited in tumors at baseline and in ICB non-responders, correlating with its low abundance. Taking advantage of the genetic screen, we demonstrate that ablation of the top hit, TRAF2, lowers the TNF cytotoxicity threshold in tumors by redirecting TNF signaling to favor RIPK1-dependent apoptosis. TRAF2 loss greatly enhanced the therapeutic potential of pharmacologic inhibition of its interaction partner cIAP, another screen hit, thereby cooperating with ICB. Our results suggest that selective reduction of the TNF cytotoxicity threshold increases the susceptibility of tumors to immunotherapy.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Imunoterapia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Humanos , Proteínas Inibidoras de Apoptose/metabolismo , Interferon gama/metabolismo , Estimativa de Kaplan-Meier , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/mortalidade , Neoplasias/terapia , RNA Guia de Cinetoplastídeos/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Receptores de Interferon/deficiência , Receptores de Interferon/genética , Transdução de Sinais/efeitos dos fármacos , Fator 2 Associado a Receptor de TNF/deficiência , Fator 2 Associado a Receptor de TNF/genética , Fator de Necrose Tumoral alfa/farmacologia , Receptor de Interferon gamaRESUMO
BACKGROUND: In recent years, GATA-binding protein 3 (GATA3) has been indicated as a marker showing good prognosis in breast cancer. In luminal breast cancer, which has good a prognosis, it shows more significant elevation in small-sized and low-grade tumors. In contrast, Ki-67 is defined as a poor prognostic factor. The aim of this study was to emphasise the prognostic importance of GATA3 and the inverse relationship with Ki-67. MATERIALS AND METHODS: In our study, 90 patients with invasive ductal breast cancer were immunohistochemically evaluated for Ki-67 and GATA3 expression. The relationship between GATA3 and Ki-67 expression was examined. In addition, the relationship between these two factors with estrogen, progesterone, human epidermal growth factor 2 receptor antibodies and other prognostic parameters such as disease-free survival and local recurrence was investigated. We accepted the level of ≥5% nüclear reaction as positive for GATA 3. A Ki-67 cut-off value of 20% was accepted as positive. RESULTS: In GATA3 positive breast cancers, good prognostic parameters were seen including high estrogen receptor (ER) positivity, progesterone receptor (PR) positivity, small tumor size and low histological grade as well as low Ki-67 expression. In breast cancers showing high Ki-67 expression, ER, PR, and GATA3 positivity were lower and there was higher human epidermal growth factor receptor 2 (HER2) positivity and high histological grade while the tumor size was larger. CONCLUSION: Our study has revealed that GATA3 has an inverse relationship with Ki-67, whereas it has a positive releationship with good prognostic factors.