RESUMO
Chronic graft-vs.-host disease (GVHD) is associated with morbidity, mortality, impaired quality of life, prolonged immunosuppressive (IS) therapy, and infection risk after allogeneic hematopoietic cell transplantation (HCT). Major strides have occurred in the understanding of chronic GVHD biology, NIH Consensus meetings have refined rigorous approaches to diagnosis, staging and response criteria, major interventional trials have established standard benchmarks for treatment outcome, and three agents to date have been FDA-approved for treating steroid-refractory chronic GVHD. Promising results from several recent trials have led some but not others to conclude that the risk of developing chronic GVHD is sufficiently low to by-and-large be considered a major post-HCT complication of the past. We propose that it is time to critically examine the results of contemporary GVHD prophylaxis regimens and discuss the state-of-the-science and associated controversies in spectrum of conclusions reached as to the risk of chronic GVHD. With these data, the current chronic GVHD incidence can be most precisely determined, and the present and future burden of chronic GVHD-affected patients be accurately modeled. Through review of existing evidence, we highlight unresolved needs and opportunities to refine best GVHD prophylaxis or preemptive therapy approaches, optimize established chronic GVHD therapy, and make the argument that support of preclinical and clinical research is critical in improving patient outcomes.
RESUMO
The interplay between T-cell states of differentiation, dysfunction, and treatment response in acute myeloid leukemia (AML) remains unclear. Here, we leveraged a multimodal approach encompassing high-dimensional flow cytometry and single-cell transcriptomics and found that early memory CD8+ T cells are associated with therapy response and exhibit a bifurcation into two distinct terminal end states. One state is enriched for markers of activation, whereas the other expresses NK-like and senescence markers. The skewed clonal differentiation trajectory towards CD8+ senescence was also a hallmark indicative of therapy resistance. We validated these findings by generating an AML CD8+ single-cell atlas integrating our data and other independent datasets. Finally, our analysis revealed that an imbalance between CD8+ early memory and senescent-like cells is linked to AML treatment refractoriness and poor survival. Our study provides crucial insights into the dynamics of CD8+ T-cell differentiation and advances our understanding of CD8+ T-cell dysfunction in AML.
RESUMO
Current anticancer therapies cannot eliminate all cancer cells, which hijack normal arginine methylation as a means to promote their maintenance via unknown mechanisms. Here we show that targeting protein arginine N-methyltransferase 9 (PRMT9), whose activities are elevated in blasts and leukemia stem cells (LSCs) from patients with acute myeloid leukemia (AML), eliminates disease via cancer-intrinsic mechanisms and cancer-extrinsic type I interferon (IFN)-associated immunity. PRMT9 ablation in AML cells decreased the arginine methylation of regulators of RNA translation and the DNA damage response, suppressing cell survival. Notably, PRMT9 inhibition promoted DNA damage and activated cyclic GMP-AMP synthase, which underlies the type I IFN response. Genetically activating cyclic GMP-AMP synthase in AML cells blocked leukemogenesis. We also report synergy of a PRMT9 inhibitor with anti-programmed cell death protein 1 in eradicating AML. Overall, we conclude that PRMT9 functions in survival and immune evasion of both LSCs and non-LSCs; targeting PRMT9 may represent a potential anticancer strategy.