Department of Internal Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Vienna, Austria.
Ludwig Boltzmann Institute for Hematology & Oncology, Medical University of Vienna, Vienna, Austria.
Stem Cells Transl Med. 2020 Nov;9(11):1331-1343. doi: 10.1002/sctm.20-0147. Epub 2020 Jul 13.
Despite new insights in molecular features of leukemic cells and the availability of novel treatment approaches and drugs, acute myeloid leukemia (AML) remains a major clinical challenge. In fact, many patients with AML relapse after standard therapy and eventually die from progressive disease. The basic concept of leukemic stem cells (LSC) has been coined with the goal to decipher clonal architectures in various leukemia-models and to develop curative drug therapies by eliminating LSC. Indeed, during the past few years, various immunotherapies have been tested in AML, and several of these therapies follow the strategy to eliminate relevant leukemic subclones by introducing LSC-targeting antibodies or LSC-targeting immune cells. These therapies include, among others, new generations of LSC-eliminating antibody-constructs, checkpoint-targeting antibodies, bi-specific antibodies, and CAR-T or CAR-NK cell-based strategies. However, responses are often limited and/or transient which may be due to LSC resistance. Indeed, AML LSC exhibit multiple forms of resistance against various drugs and immunotherapies. An additional problems are treatment-induced myelotoxicity and other side effects. The current article provides a short overview of immunological targets expressed on LSC in AML. Moreover, cell-based therapies and immunotherapies tested in AML are discussed. Finally, the article provides an overview about LSC resistance and strategies to overcome resistance.
尽管在白血病细胞的分子特征方面有了新的认识,并且有了新的治疗方法和药物,但急性髓细胞白血病(AML)仍然是一个主要的临床挑战。事实上,许多 AML 患者在标准治疗后复发,最终死于疾病进展。白血病干细胞(LSC)的基本概念是为了解释各种白血病模型中的克隆结构,并通过消除 LSC 来开发治愈性药物治疗。事实上,在过去的几年中,已经在 AML 中测试了各种免疫疗法,其中一些疗法通过引入针对 LSC 的抗体或针对 LSC 的免疫细胞来消除相关的白血病亚克隆,从而遵循消除 LSC 的策略。这些疗法包括新一代的 LSC 消除抗体构建物、检查点靶向抗体、双特异性抗体以及基于 CAR-T 或 CAR-NK 细胞的策略。然而,反应往往是有限的和/或短暂的,这可能是由于 LSC 耐药性所致。事实上,AML LSC 对各种药物和免疫疗法表现出多种形式的耐药性。另一个问题是治疗引起的骨髓毒性和其他副作用。本文简要概述了 AML 中 LSC 上表达的免疫靶标。此外,还讨论了在 AML 中测试的基于细胞的疗法和免疫疗法。最后,本文概述了 LSC 耐药性以及克服耐药性的策略。