This cluster captures a maturing wave of targeted cellular and genetic therapies for hematologic malignancies, centered on the challenge of achieving tumor specificity while minimizing collateral toxicity. In acute myeloid leukemia (AML), both CAR T-cell and CAR NK cell platforms have expanded their targeting repertoire well beyond CD33 to include CD123, CLL-1, CD70, TIM-3, and FLT3, reflecting an antigen-diversification strategy aimed at overcoming the intrinsic difficulty of finding leukemia-restricted surface markers. This diversification is a direct response to on-target/off-tumor toxicity, the field's most persistent obstacle, since most AML antigens are shared with healthy myeloid and hematopoietic stem/progenitor cells. A particularly novel countermeasure—CAR constructs targeting mismatched HLA-DRB1—illustrates an emerging strategy for post-alloHCT relapse, exploiting donor-recipient genetic disparity rather than tumor-lineage antigens to improve specificity. Institutional reviews (e.g., Osaka University) synthesizing this landscape signal that CAR NK cell therapy is increasingly positioned as a complementary or alternative modality to CAR T cells, potentially offering reduced toxicity profiles.
Underlying biological vulnerabilities are being mapped with increasing molecular resolution. Monosomy 7, present in 10-20% of myeloid neoplasms (AML and MDS) and linked to poor prognosis, has been characterized through epi-transcriptomic profiling to reveal both a 49-gene stemness program and dysfunction of the TIGIT-PVRIG-DNAM1/CD112 immunological axis, which suppresses NK cell cytolytic activity. This mechanistic insight connects impaired innate immune surveillance to disease aggressiveness and suggests that restoring NK function or targeting checkpoint components in this axis could synergize with CAR NK approaches. In parallel, menin inhibitors have emerged as a genotype-driven targeted therapy for acute leukemias (AML and ALL) harboring KMT2A or NPM1 mutations, exemplifying the broader shift toward mutation-informed treatment selection alongside cellular immunotherapy.
A parallel but mechanistically distinct thread involves multiple myeloma, where functionally high-risk disease—defined by progression within 24 months of frontline therapy—is associated with extramedullary spread, high tumor burden, and markedly inferior overall survival following late-line CAR T-cell therapy, as shown in the 208-patient MSKCC retrospective cohort. This underscores that even effective cellular therapies face ceiling effects in biologically aggressive, treatment-refractory disease states, reinforcing the need for earlier intervention or combination strategies in high-risk populations.
Finally, the inclusion of QuadPE, a quadruple pegRNA prime editing strategy enabling efficient (~40%) and precise insertion of large DNA fragments (up to 26 kb) in non-dividing cells such as post-mitotic neurons and in human primary T cells, signals a foundational technological advance poised to reshape CAR T-cell engineering itself. By outperforming transposase-based integration systems and enabling programmable large genomic insertions, QuadPE addresses a critical bottleneck in both gene therapy for monogenic/rare diseases and the manufacturing of next-generation CAR constructs—suggesting that future CAR T and CAR NK platforms may be engineered with greater precision, multiplexed antigen constructs, and reduced off-target genomic disruption.