Chimeric antigen receptor T cell therapies for acute myeloid leukemia

Abstract

Chimeric antigen receptor T cell (CAR T) therapies have achieved unprecedented efficacy in B-cell tumors, prompting scientists and doctors to exploit this strategy to treat other tumor types. Acute myeloid leukemia (AML) is a group of heterogeneous myeloid malignancies. Relapse remains the main cause of treatment failure, especially for patients with intermediate or high risk stratification. Allogeneic hematopoietic stem cell transplantation could be an effective therapy because of the graft-versus-leukemia effect, which unfortunately puts the patient at risk of serious complications, such as graft-versus-host disease. Although the identification of an ideal target antigen for AML is challenging, CAR T therapy remains a highly promising strategy for AML patients, particularly for those who are ineligible to receive a transplantation or have positive minimal residual disease. In this review, we focus on the most recent and promising advances in CAR T therapies for AML.

Keywords

acute myeloid leukemia / CAR T / immunotherapy

1 Introduction

Acute myeloid leukemia (AML) is the most common type of leukemia showing heterogeneity behavior and is characterized by the clonal expansion of myeloid blasts. Despite recent improvements in treatment, the complete remission (CR) rates for AML are approximately 70% in younger adults and only 40%–60% in older patients (more than 60 years old) [1,2]. Disease recurrence remains the most common cause of treatment failure, and the 5-year survival of AML patients with intermediate and high risk cytogenetics was no more than 41% [3–5].

Allogeneic hematopoietic stem cell transplantation (Allo-HSCT) could be an effective therapy for AML patients through the graft-versus-leukemia effect mediated by donor T lymphocytes. However, it is often accompanied with the risk of life-threatening graft-versus-host disease [6]. The physiological mechanism responsible for the killing effect of cytotoxic T lymphocytes has been well studied. A recognition signal from T cell receptors (TCRs) is the first step; this is complemented by a costimulatory signal to further augment the activation of cytotoxic T lymphocytes (Fig. 1). A TCR could recognize an antigen in the context of major histocompatibility complex (MHC) presentation. In stark contrast, chimeric antigen receptor (CAR) is an MHC-independent model that is commonly composed of an extracellular domain with a single-chain variable fragment (scFv) from a monoclonal antibody, a hinge region, a transmembrane domain, and a TCR-derived CD3z domain with or without one or more intracellular costimulatory domains. The design of CAR has developed over the years to boost efficacy and safety in detailed immunological structures (Fig. 2).

One of the most important prerequisites for successful CAR T therapy is the identification of the suitable target antigens [7,8]. Theoretically, an ideal target antigen should be immunogenic and should play a crucial role in the differentiation, survival, and expansion of malignant cells. The antigen expression should be restricted to all malignant cells with high antigen densities [9,10], even including malignant stem cells. A large fraction of patients should be positive for the antigen, which should be on the surface of malignant cells. CD19, which is ubiquitously expressed on the surface of B cell, is a satisfying target for B cell malignancies. Infusion with anti-CD19 CAR T resulted in an unheard-of antitumor effect and long-term remissions in chronic lymphocytic and acute lymphocytic leukemia [11–13]. Unlike B cell malignancies, different antigens are expressed on distinct subtype AML cells, which means that we cannot treat all AML patients with CAR T targeting the same antigen. In the following paragraphs we will focus on CAR T therapies in AML.

2 CAR T therapies for AML

As of this writing, there is no licensing authority approving CAR T therapy for AML in contrast to B cell malignancies, but several antigens have been proposed as potential CAR T targets against AML (Table 1). The greatest challenge for the successful application of CAR T for patients with AML is the selection of effective and safe antigen targets. AML is a heterogeneous clonal malignancy, and the subclones may evolve over time, thereby possibly leading to the genetic and phenotypic heterogeneity of the leukemia cells in one patient [14]. Phenotypic heterogeneity is characterized by differential antigen expression on the leukemia cell surface, especially in patients suffering from leukemia relapse. During the relapse stage, for B-ALL, leukemia cells lose the target antigen, generate antigen-negative blast cells, or exhaust CAR T persistence [15–19]. However, the study on anti-LeY CAR T for five AML patients showed that the AML blasts of three patients present at relapse continued to express the LeY antigen, indicating that progression was not due to the antigenic change in these AML cases [20]. It might be necessary to target more than one antigen to optimize the anti-leukemia effect of CAR T. Perna et al. developed the combinatorial CAR therapy for AML with the aid of high-throughput surfaceome expression data. The ideal antigen pair should be at a very low level of expression in normal tissues and CD34⁺CD38⁻ hematopoietic stem cells to minimize the toxic side effect; the combination expressions need to be in all tumor cells (including leukemia stem cells) to overcome clonal heterogeneity and minimize the risk of antigen escape [21] (Fig. 3A and 3B).

3 Anti-CD33 CAR T

CD33 is a transmembrane receptor that binds to sialic acid and is expressed on about 85%–90% of AML blast cells. It is also present in early multilineage hematopoietic progenitors, bone marrow mononuclear cell precursors, and hepatocytes, thereby possibly causing the toxicity of veno-occlusive liver disease and limiting the use of CD33-directed immunotherapies [22]. Preclinical studies provide data on the effectiveness of an anti-CD33 CAR T therapy for AML in mice and support its development as a clinical therapeutic approach [23,24]. Considering the potential toxicity associated with targeting CD33 in patients, Rafiq et al. created the EGFRt/HuM195-28z/IL-12 CAR T, in which an elimination gene was included to allow CAR T clearance after disease remission (Fig. 3C), and tested anti-tumor efficacy in two preclinical mouse models of AML in vivo [25]. Wang et al. reported that a 41-year-old male patient with AML was administered a total of 1.12 × 10⁹ autologous anti-CD33 CAR T, of which ~38% were transduced with CAR. After 2 weeks of tolerable side effects, including fever and jaundice, the patient had a dramatic decrease of blasts in the bone marrow, but the leukemia cells gradually increased 9 weeks after therapy [26]. Based on these inspiring preliminary results, some ongoing clinical trials on anti-CD33 CAR T therapy were conducted (Table 1). To accurately target AML cells without affecting normal hematopoiesis, Kim et al. produced CD33 knockout human hematopoietic stem cells and progenitor cells (HSPCs) and demonstrated normal implantation and differentiation in immunodeficient mice. Human HSPCs lacking CD33 could obviate the attack of anti-CD33 CAR T, which would efficaciously eliminate leukemia cells without marrow toxicity [27]. To achieve this same goal, Humbert et al. definitively eliminated CD33 exon2 by CRISPR/Cas9 technology, thereby expressing a shorter isoform of CD33 but not the full-type CD33. They also evaluated the genome-edited HSPCs in vitro and in immunodeficient mice to reserve the function of engraftment and avoid the non-leukemic cytotoxicity [28]. Borot et al. also used CRISPR/Cas9 to ablate CD33 antigen in HSPCs and demonstrated that the infusion of CD33-deleted HSPCs and anti-CD33 CAR T accomplished the clearance of blast cells without myelosuppression [29].

4 Anti-CD123 CAR T

CD123, a transmembrane a subunit of the IL-3 receptor, which is highly expressed on AML blasts and leukemia stem cells, represents another attractive target for immunotherapy [30–32]. Du et al. demonstrated the role of CD123 epitope selection in immunotoxin action and further found that 26292(Fv)-PE38-KDEL has good cytotoxic activity against CD123 positive cell lines [33]. The use of CD123-targeted T cells could be an encouraging strategy for the potential clearance of AML cells [34,35]. Gills et al. showed that the donor-derived anti-CD123-41BB CAR T had graft-versus-leukemia (GVL) effect after infusion in an acute myeloid leukemia xenograft model with NSG mice [35], as well as also other CD123 positive malignancies [36]. Based on those preclinical results, many clinical trials have been launched to evaluate the therapeutic efficacy of anti-CD123 CAR T in AML patients (Table 1). Meanwhile, CD123 is infrequently expressed on HSPCs [37]. The potential influence on hematopoiesis that anti-CD123 CAR T may induce needs to be recognized. For purpose of controlling harmful off-target toxicities, Wang et al. had included EGFRt in their lentiviral construct to provide a target for the elimination of CAR T in vivo [38]. Straathof et al. showed a late-stage apoptosis pathway molecule, caspase-9, which can be stably expressed in T lymphocytes while retaining their phenotype and function to regulate CAR T abilities through inducible caspase-9 apoptosis switch [39].

5 Anti-NKG2D CAR T

NKG2D, which is an activating receptor on NK cells, invariant NKT cells, gd T cells, CD8⁺ T cells, and a small fraction of CD4⁺ T cells, provides a costimulatory signal to T cells in its native form. NKG2D ligands are expressed on some solid tumors and hematologic malignancies, including AML and MM, but are generally not on healthy tissues [40]. NKG2D ligand recognition by the anti-NKG2D CAR T mediates T cell activation. Therefore, anti-NKG2D CAR T has the potential to treat these malignancies. Hilpert et al. demonstrated that anti-NKG2D CAR T was effective in eradicating established multiple myeloma (MM), lymphoma, and ovarian cancers in murine studies, and it can induce autologous immunity against tumor even when anti-NKG2D CAR T can no longer be detected [41]. Human anti-NKG2D CAR T does not attack autologous peripheral blood mononuclear cells or bone marrow cells from healthy donors in vitro. Baumeister et al. conducted a phase I dose-escalation study to evaluate the safety and feasibility of anti-NKG2D CAR T for AML/myelodysplastic syndrome and relapsed/refractory MM. Twelve patients (including 7 AML, 5 MM) were infused with anti-NKG2D CAR T, and the dosages were evaluated in four levels (1×10⁶–3×10⁷ total viable T cells) [42]. There were no adverse events more than grade 3 or significant autoimmune reactions attributable to anti-NKG2D CAR T infusion, although no clinical leukemic responses were obtained up to 28 days after infusion. Further studies investigating the efficacy of multiple anti-NKG2D CAR T infusions are currently underway.

6 Anti-Lewis Y CAR T

Lewis Y (LeY) is a difucosylated carbohydrate antigen expressed on many malignancies including AML, but it is limited to normal tissue [43–45]. Peinert et al. demonstrated that anti-LeY CAR T produced varying amounts of IFN-g on exposure to AML cells and displayed apparent cytolytic activity in a preclinical study [45]. Ritchie et al. examined the safety and efficacy of second generation CAR T against the LeY antigen in AML in a phase I study [20]. Out of four evaluated patients, one achieved cytogenetic remission for 5 months, whereas another with active leukemia showed a decrease in peripheral blood blasts, and another showed stable disease for 23 months. No grade 3 or 4 adverse events or CRS were observed. Although all the patients eventually relapsed, serial PCR for detection of the LeY transgene demonstrated that infused CAR T could persist for up to 10 months.

7 Anti-CD19 CAR T

A fraction of AML patients could relatively highly express the antigen of CD19, which can be marked with the anti-CD19 CAR T regardless of cell origin. Ma et al. identified 527 AML cases from 1/1/2012 to 10/20/2017 at Stony Brook University Hospital and found that 17 out of 527 (3.2%) AML patients expressed CD19 [46]. Even at a low effector:target cell ratio of 2:1, anti-CD19 CAR T was able to effectively extinguish AML blast cells expressing CD19 within 6 h, suggesting that anti-CD19 CAR T therapy may be potentially applied for CD19⁺ AML. These CD19⁺ AML patients are distinguished from mixed phenotype acute leukemia according to the World Health Organization classification [47].

8 Promising target antigens for AML

FMS-like tyrosine kinase 3 (FLT3), also known as CD135, is a transmembrane protein expressed on malignant blasts in AML and retained on normal hematopoietic stem and progenitor cells. In the preclinical research, Jetani et al. reported that anti-FLT3 CAR T demonstrated potent reactivity against AML cell lines and primary AML blasts, which expressed either wild-type FLT3 or FLT3 with internal tandem duplication (FLT3-ITD) [48]. In addition, they showed that the FLT3-inhibitor Crenolanib could further increase the expression of FLT3 particularly on FLT3-ITD⁺ AML blast cells, which rendered the AML cells more susceptible to attack by anti-FLT3 CAR T in vitro and in vivo. Unfortunately, anti-FLT3 CAR T could also recognize normal hematopoietic stem cells and impair normal hematopoiesis in vitro and in vivo, indicating that anti-FLT3 CAR T therapy will require subsequent CAR T depletion and Allo-HSCT to reconstitute the hematopoietic system. Notably, the specific cytotoxicity of anti-FLT3 CAR T against FLT3⁺ leukemia cell lines and primary AML cells was also demonstrated in vitro and in xenograft mouse models in other studies [49,50].

CD7 is expressed in more than 90% of lymphoblastic T cell leukemia and lymphoma and in approximately 30% of AML patients [51–54], but it is absent in normal erythroid and myeloid cells. CD7 expression of AML blasts is associated with poor prognosis. Thus, targeting CD7 could be beneficial for these AML patients. Gomes-Silva et al. showed that CD7-directed CART from CD7 gene-edited (CD7^KO) T cells was capable of decimating CD7⁺ AML cell lines while sparing myeloid and erythroid progenitor cells [55], thereby supporting the feasibility of using anti-CD7 CAR T for the treatment of CD7⁺ AML.

C-type lectin-like molecule 1 (CLL1), also known as CD371, is a type II transmembrane glycoprotein highly expressed on the blast cells of AML, but it is also on normal myeloid cells. CLL1 is lowly expressed on normal hematopoietic stem cells [56]. CLL1 is considered as a promising CAR T target. There are several preclinical studies on anti-CLL1 CAR T. Wang et al. generated CLL-1-redirected CAR T carrying a CAR composed of a CLL1 specific single chain variable fragment in combination with CD28/4-1BB costimulatory domains, and CD3z signaling domain [57]; this CAR T specifically lysed CLL-1⁺ cell lines and patient-derived AML cells in vitro and showed strong anti-leukemic activity in the xenograft model of disseminated AML. In agreement with this finding, several other groups also demonstrated the potent activity of anti-CLL-1 CAR T against CLL1⁺ AML cell lines in vitro and in xenograft mouse models [58–60].

CD44v6, the isoform variant 6 of the hyaluronic acid receptor CD44, is a class I membrane glycoprotein and is expressed in hematologic malignancies such as AML [61]. CD44v6 is absent on hematopoietic stem cells and only shows a low level of expression on normal cells, including monocytes, activated T cells, and keratinocytes [61,62]. Casucci et al. constructed a second generation anti-CD44v6 CAR T targeting AML cells while sparing normal HSPCs [62], and they also demonstrated the feasibility of incorporation of a suicide gene in the CAR structure to improve the safety of anti-CD44v6 CAR T given that anti-CD44v6 CAR T could potentially damage normal monocytes and keratinocytes.

Folate receptor β (FRβ) is expressed on ~70% of primary AML patient tumors, and its expression can be raised on AML blasts by all-trans retinoic acid (ATRA) [63,64]. In preclinical models, the effect of folate-conjugated drug therapy against FRβ-positive AML was improved when combined with ATRA [64]. Lynn et al. displayed the efficacy of anti-FRβ CART and the better efficacy of high-affinity anti-FRβ CART against AML cells in vitro and in vivo without toxicity on normal hematopoietic stem cells [65,66].

The main challenge in CAR T therapy for AML is the discovery of targets as favorable as CD19 for ALL. Perna et al. outlined a framework describing the ideal characteristics of CAR targets and established a methodological analysis for mining composite high-throughput surfaceome expression data [21]. They optimized combinative target selection based on expression profiles in malignant and normal tissues. This approach provided the foundation for intellectual design of CAR therapies for AML and a guide for combinatorial targeting, and they screened out four promising targets, namely, ADGRE2, CCR1, CD70, and LILRB2. To enhance the efficiency of targeting antigens while mitigating toxicity, the combinatorial strategy of dual CAR was projected.

9 CAR T therapy plus Allo-HSCT

Historically, Allo-HSCT is recommended for patients with refractory/relapsed acute leukemia during the CR period, and the minimal residual disease (MRD) level before transplantation was considered as an independent prognostic factor. Recently, the encouraging efficacy of CD19-targeted CAR T therapy has begun to challenge this algorithm for B cell malignancies. However, up to this date, no available clinical trial data on AML can be used to make a definitive Allo-HSCT recommendation. It remains uncertain whether patients in remission post-CAR T therapy should be administered with Allo-HSCT and whether CAR T therapy is sufficient for AML patients. According to these unsatisfactory long-term data on CD19 CAR T therapy for relapsed/refractory B-ALL [67–70] and the results of early clinical studies on anti-LeY CAR T for patients with relapsed AML [20], we speculate that CAR T therapy for AML should be considered as a “bridge” to Allo-HSCT rather than a replacement. CAR T therapy could strive for an opportunity for disease remission and induce a deeper MRD-level prior to Allo-HSCT. However, CAR T therapy could be used as a regimen for patients with relapsed disease post-transplantation. We believe that the consolidative Allo-HSCT following CAR T therapy in eligible AML patients could represent a very promising therapeutic strategy that has the potential to decrease the risk of relapse, although this idea warrants further investigation.

10 Summary and perspective

The value of CAR T therapy for AML remains to be determined. As the general background of CAR T technology evolves, CAR T therapies for AML will improve. The design of CAR with optimized antigen recognition, different costimulatory, hinge, and transmembrane domains will improve the affinity of the CAR T and minimize toxicity. Further studies involving the optimization of ex vivo culture conditions and genetic manipulation of CAR structure are needed. Combination therapies may be necessary to achieve a better outcome.

References

[1] Döhner H, Weisdorf DJ, Bloomfield CD. Acute myeloid leukemia. N Engl J Med 2015; 373(12): 1136–1152

[2] Appelbaum FR, Gundacker H, Head DR, Slovak ML, Willman CL, Godwin JE, Anderson JE, Petersdorf SH. Age and acute myeloid leukemia. Blood 2006; 107(9): 3481–3485

[3] Mrózek K, Marcucci G, Nicolet D, Maharry KS, Becker H, Whitman SP, Metzeler KH, Schwind S, Wu YZ, Kohlschmidt J, Pettenati MJ, Heerema NA, Block AW, Patil SR, Baer MR, Kolitz JE, Moore JO, Carroll AJ, Stone RM, Larson RA, Bloomfield CD. Prognostic significance of the European LeukemiaNet standardized system for reporting cytogenetic and molecular alterations in adults with acute myeloid leukemia. J Clin Oncol 2012; 30(36): 4515–4523

[4] Röllig C, Bornhäuser M, Thiede C, Taube F, Kramer M, Mohr B, Aulitzky W, Bodenstein H, Tischler HJ, Stuhlmann R, Schuler U, Stölzel F, von Bonin M, Wandt H, Schäfer-Eckart K, Schaich M, Ehninger G. Long-term prognosis of acute myeloid leukemia according to the new genetic risk classification of the European LeukemiaNet recommendations: evaluation of the proposed reporting system. J Clin Oncol 2011; 29(20): 2758–2765

[5] Byrd JC, Mrózek K, Dodge RK, Carroll AJ, Edwards CG, Arthur DC, Pettenati MJ, Patil SR, Rao KW, Watson MS, Koduru PR, Moore JO, Stone RM, Mayer RJ, Feldman EJ, Davey FR, Schiffer CA, Larson RA, Bloomfield CD; Cancer and Leukemia Group B (CALGB 8461). Pretreatment cytogenetic abnormalities are predictive of induction success, cumulative incidence of relapse, and overall survival in adult patients with de novo acute myeloid leukemia: results from Cancer and Leukemia Group B (CALGB 8461). Blood 2002; 100(13): 4325–4336

[6] Cornelissen JJ, Gratwohl A, Schlenk RF, Sierra J, Bornhäuser M, Juliusson G, Råcil Z, Rowe JM, Russell N, Mohty M, Löwenberg B, Socié G, Niederwieser D, Ossenkoppele GJ. The European LeukemiaNet AML Working Party consensus statement on allogeneic HSCT for patients with AML in remission: an integrated-risk adapted approach. Nat Rev Clin Oncol 2012; 9(10): 579–590

[7] Maus MV, Grupp SA, Porter DL, June CH. Antibody-modified T cells: CARs take the front seat for hematologic malignancies. Blood 2014; 123(17): 2625–2635

[8] Wei J, Han X, Bo J, Han W. Target selection for CAR-T therapy. J Hematol Oncol 2019; 12(1): 62

[9] Drent E, Themeli M, Poels R, de Jong-Korlaar R, Yuan H, de Bruijn J, Martens ACM, Zweegman S, van de Donk N, Groen RWJ, Lokhorst HM, Mutis T. A rational strategy for reducing on-target off-tumor effects of CD38-chimeric antigen receptors by affinity optimization. Mol Ther 2017; 25(8): 1946–1958

[10] Walker AJ, Majzner RG, Zhang L, Wanhainen K, Long AH, Nguyen SM, Lopomo P, Vigny M, Fry TJ, Orentas RJ, Mackall CL. Tumor antigen and receptor densities regulate efficacy of a chimeric antigen receptor targeting anaplastic lymphoma kinase. Mol Ther 2017; 25(9): 2189–2201

[11] Porter DL, Levine BL, Kalos M, Bagg A, June CH. Chimeric antigen receptor-modified T cells in chronic lymphoid leukemia. N Engl J Med 2011; 365(8): 725–733

[12] Grupp SA, Kalos M, Barrett D, Aplenc R, Porter DL, Rheingold SR, Teachey DT, Chew A, Hauck B, Wright JF, Milone MC, Levine BL, June CH. Chimeric antigen receptor-modified T cells for acute lymphoid leukemia. N Engl J Med 2013; 368(16): 1509–1518

[13] Ceppi F, Gardner RA. Chimeric antigen receptor T cells for B-cell acute lymphoblastic leukemia. Cancer J 2019; 25(3): 191–198

[14] Papaemmanuil E, Gerstung M, Bullinger L, Gaidzik VI, Paschka P, Roberts ND, Potter NE, Heuser M, Thol F, Bolli N, Gundem G, Van Loo P, Martincorena I, Ganly P, Mudie L, McLaren S, O’Meara S, Raine K, Jones DR, Teague JW, Butler AP, Greaves MF, Ganser A, Döhner K, Schlenk RF, Döhner H, Campbell PJ. Genomic classification and prognosis in acute myeloid leukemia. N Engl J Med 2016; 374(23): 2209–2221

[15] Sotillo E, Barrett DM, Black KL, Bagashev A, Oldridge D, Wu G, Sussman R, Lanauze C, Ruella M, Gazzara MR, Martinez NM, Harrington CT, Chung EY, Perazzelli J, Hofmann TJ, Maude SL, Raman P, Barrera A, Gill S, Lacey SF, Melenhorst JJ, Allman D, Jacoby E, Fry T, Mackall C, Barash Y, Lynch KW, Maris JM, Grupp SA, Thomas-Tikhonenko A. Convergence of acquired mutations and alternative splicing of CD19 enables resistance to CART-19 immunotherapy. Cancer Discov 2015; 5(12): 1282–1295

[16] Gardner R, Wu D, Cherian S, Fang M, Hanafi LA, Finney O, Smithers H, Jensen MC, Riddell SR, Maloney DG, Turtle CJ. Acquisition of a CD19-negative myeloid phenotype allows immune escape of MLL-rearranged B-ALL from CD19 CAR-T-cell therapy. Blood 2016; 127(20): 2406–2410

[17] Jacoby E, Nguyen SM, Fountaine TJ, Welp K, Gryder B, Qin H, Yang Y, Chien CD, Seif AE, Lei H, Song YK, Khan J, Lee DW, Mackall CL, Gardner RA, Jensen MC, Shern JF, Fry TJ. CD19 CAR immune pressure induces B-precursor acute lymphoblastic leukaemia lineage switch exposing inherent leukaemic plasticity. Nat Commun 2016; 7(12320): 12320

[18] Sadelain M. Chimeric antigen receptors: driving immunology towards synthetic biology. Curr Opin Immunol 2016; 41: 68–76

[19] Yu H, Sotillo E, Harrington C, Wertheim G, Paessler M, Maude SL, Rheingold SR, Grupp SA, Thomas-Tikhonenko A, Pillai V. Repeated loss of target surface antigen after immunotherapy in primary mediastinal large B cell lymphoma. Am J Hematol 2017; 92(1): E11–E13

[20] Ritchie DS, Neeson PJ, Khot A, Peinert S, Tai T, Tainton K, Chen K, Shin M, Wall DM, Honemann D, Gambell P, Westerman DA, Haurat J, Westwood JA, Scott AM, Kravets L, Dickinson M, Trapani JA, Smyth MJ, Darcy PK, Kershaw MH, Prince HM. Persistence and efficacy of second generation CAR T cell against the LeY antigen in acute myeloid leukemia. Mol Ther 2013; 21(11): 2122–2129

[21] Perna F, Berman SH, Soni RK, Mansilla-Soto J, Eyquem J, Hamieh M, Hendrickson RC, Brennan CW, Sadelain M. Integrating proteomics and transcriptomics for systematic combinatorial chimeric antigen receptor therapy of AML. Cancer Cell 2017; 32(4): 506–519.e5

[22] Giles FJ, Kantarjian HM, Kornblau SM, Thomas DA, Garcia-Manero G, Waddelow TA, David CL, Phan AT, Colburn DE, Rashid A, Estey EH. Mylotarg (gemtuzumab ozogamicin) therapy is associated with hepatic venoocclusive disease in patients who have not received stem cell transplantation. Cancer 2001; 92(2): 406–413

[23] Kenderian SS, Ruella M, Shestova O, Klichinsky M, Aikawa V, Morrissette JJ, Scholler J, Song D, Porter DL, Carroll M, June CH, Gill S. CD33-specific chimeric antigen receptor T cells exhibit potent preclinical activity against human acute myeloid leukemia. Leukemia 2015; 29(8): 1637–1647

[24] O’Hear C, Heiber JF, Schubert I, Fey G, Geiger TL. Anti-CD33 chimeric antigen receptor targeting of acute myeloid leukemia. Haematologica 2015; 100(3): 336–344

[25] Rafiq S, Purdon TJ, Schultz LM, Brentjens RJ. CD33-directed chimeric antigen receptor (CAR) T cells for the treatment of acute myeloid leukemia (AML). Blood 2016; 128(22): 2825

[26] Wang QS, Wang Y, Lv HY, Han QW, Fan H, Guo B, Wang LL, Han WD. Treatment of CD33-directed chimeric antigen receptor-modified T cells in one patient with relapsed and refractory acute myeloid leukemia. Mol Ther 2015; 23(1): 184–191

[27] Kim MY, Yu KR, Kenderian SS, Ruella M, Chen S, Shin TH, Aljanahi AA, Schreeder D, Klichinsky M, Shestova O, Kozlowski MS, Cummins KD, Shan X, Shestov M, Bagg A, Morrissette JJD, Sekhri P, Lazzarotto CR, Calvo KR, Kuhns DB, Donahue RE, Behbehani GK, Tsai SQ, Dunbar CE, Gill S. Genetic inactivation of CD33 in hematopoietic stem cells to enable CAR T cell immunotherapy for acute myeloid leukemia. Cell 2018; 173(6): 1439–1453.e19

[28] Humbert O, Laszlo GS, Sichel S, Ironside C, Haworth KG, Bates OM, Beddoe ME, Carrillo RR, Kiem HP, Walter RB. Engineering resistance to CD33-targeted immunotherapy in normal hematopoiesis by CRISPR/Cas9-deletion of CD33 exon 2. Leukemia 2019; 33(3): 762–808

[29] Borot F, Wang H, Ma Y, Jafarov T, Raza A, Ali AM, Mukherjee S. Gene-edited stem cells enable CD33-directed immune therapy for myeloid malignancies. Proc Natl Acad Sci USA 2019; 116(24): 11978–11987

[30] Testa U, Riccioni R, Diverio D, Rossini A, Lo Coco F, Peschle C. Interleukin-3 receptor in acute leukemia. Leukemia 2004; 18(2): 219–226

[31] Jin L, Lee EM, Ramshaw HS, Busfield SJ, Peoppl AG, Wilkinson L, Guthridge MA, Thomas D, Barry EF, Boyd A, Gearing DP, Vairo G, Lopez AF, Dick JE, Lock RB. Monoclonal antibody-mediated targeting of CD123, IL-3 receptor alpha chain, eliminates human acute myeloid leukemic stem cells. Cell Stem Cell 2009; 5(1): 31–42

[32] Du X, Ho M, Pastan I. New immunotoxins targeting CD123, a stem cell antigen on acute myeloid leukemia cells. J Immunother 2007; 30(6): 607–613

[33] Mardiros A, Dos Santos C, McDonald T, Brown CE, Wang X, Budde LE, Hoffman L, Aguilar B, Chang WC, Bretzlaff W, Chang B, Jonnalagadda M, Starr R, Ostberg JR, Jensen MC, Bhatia R, Forman SJ. T cells expressing CD123-specific chimeric antigen receptors exhibit specific cytolytic effector functions and antitumor effects against human acute myeloid leukemia. Blood 2013; 122(18): 3138–3148

[34] Gill S, Tasian SK, Ruella M, Shestova O, Li Y, Porter DL, Carroll M, Danet-Desnoyers G, Scholler J, Grupp SA, June CH, Kalos M. Preclinical targeting of human acute myeloid leukemia and myeloablation using chimeric antigen receptor-modified T cells. Blood 2014; 123(15): 2343–2354

[35] Ruella M, Barrett DM, Kenderian SS, Shestova O, Hofmann TJ, Perazzelli J, Klichinsky M, Aikawa V, Nazimuddin F, Kozlowski M, Scholler J, Lacey SF, Melenhorst JJ, Morrissette JJ, Christian DA, Hunter CA, Kalos M, Porter DL, June CH, Grupp SA, Gill S. Dual CD19 and CD123 targeting prevents antigen-loss relapses after CD19-directed immunotherapies. J Clin Invest 2016; 126(10): 3814–3826

[36] Rebmann V, Schütt P, Brandhorst D, Opalka B, Moritz T, Nowrousian MR, Grosse-Wilde H. Soluble MICA as an independent prognostic factor for the overall survival and progression-free survival of multiple myeloma patients. Clin Immunol 2007; 123(1): 114–120

[37] Taussig DC, Pearce DJ, Simpson C, Rohatiner AZ, Lister TA, Kelly G, Luongo JL, Danet-Desnoyers GA, Bonnet D. Hematopoietic stem cells express multiple myeloid markers: implications for the origin and targeted therapy of acute myeloid leukemia. Blood 2005; 106(13): 4086–4092

[38] Wang X, Chang WC, Wong CW, Colcher D, Sherman M, Ostberg JR, Forman SJ, Riddell SR, Jensen MC. A transgene-encoded cell surface polypeptide for selection, in vivo tracking, and ablation of engineered cells. Blood 2011; 118(5): 1255–1263

[39] Straathof KC, Pulè MA, Yotnda P, Dotti G, Vanin EF, Brenner MK, Heslop HE, Spencer DM, Rooney CM. An inducible caspase 9 safety switch for T-cell therapy. Blood 2005; 105(11): 4247–4254

[40] Spear P, Wu MR, Sentman ML, Sentman CL. NKG2D ligands as therapeutic targets. Cancer Immun 2013; 13(8): 8

[41] Hilpert J, Grosse-Hovest L, Grünebach F, Buechele C, Nuebling T, Raum T, Steinle A, Salih HR. Comprehensive analysis of NKG2D ligand expression and release in leukemia: implications for NKG2D-mediated NK cell responses. J Immunol 2012; 189(3): 1360–1371

[42] Baumeister SH, Murad J, Werner L, Daley H, Trebeden-Negre H, Gicobi JK, Schmucker A, Reder J, Sentman CL, Gilham DE, Lehmann FF, Galinsky I, DiPietro H, Cummings K, Munshi NC, Stone RM, Neuberg DS, Soiffer R, Dranoff G, Ritz J, Nikiforow S. Phase I trial of autologous CAR T cells targeting NKG2D ligands in patients with AML/MDS and multiple myeloma. Cancer Immunol Res 2019; 7(1): 100–112

[43] Sakamoto J, Furukawa K, Cordon-Cardo C, Yin BW, Rettig WJ, Oettgen HF, Old LJ, Lloyd KO. Expression of Lewisa, Lewisb, X, and Y blood group antigens in human colonic tumors and normal tissue and in human tumor-derived cell lines. Cancer Res 1986; 46(3): 1553–1561

[44] Westwood JA, Murray WK, Trivett M, Haynes NM, Solomon B, Mileshkin L, Ball D, Michael M, Burman A, Mayura-Guru P, Trapani JA, Peinert S, Hönemann D, Miles Prince H, Scott AM, Smyth MJ, Darcy PK, Kershaw MH. The Lewis-Y carbohydrate antigen is expressed by many human tumors and can serve as a target for genetically redirected T cells despite the presence of soluble antigen in serum. J Immunother 2009; 32(3): 292–301

[45] Peinert S, Prince HM, Guru PM, Kershaw MH, Smyth MJ, Trapani JA, Gambell P, Harrison S, Scott AM, Smyth FE, Darcy PK, Tainton K, Neeson P, Ritchie DS, Hönemann D. Gene-modified T cells as immunotherapy for multiple myeloma and acute myeloid leukemia expressing the Lewis Y antigen. Gene Ther 2010; 17(5): 678–686

[46] Ma G, Wang Y, Ahmed T, Zaslav AL, Hogan L, Avila C, Wada M, Salman H. Anti-CD19 chimeric antigen receptor targeting of CD19⁺ acute myeloid leukemia. Leuk Res Rep 2018; 9(42–44): 42–44

[47] Arber DA, Orazi A, Hasserjian R, Thiele J, Borowitz MJ, Le Beau MM, Bloomfield CD, Cazzola M, Vardiman JW. The 2016 revision to the World Health Organization classification of myeloid neoplasms and acute leukemia. Blood 2016; 127(20): 2391–2405

[48] Jetani H, Garcia-Cadenas I, Nerreter T, Thomas S, Rydzek J, Meijide JB, Bonig H, Herr W, Sierra J, Einsele H, Hudecek M. CAR T-cells targeting FLT3 have potent activity against FLT3⁻ITD⁺ AML and act synergistically with the FLT3-inhibitor crenolanib. Leukemia 2018; 32(5): 1168–1179

[49] Chien CD, Sauter C, Ishii K, Nguyen SM, Shen F, Tasian SK, Chen W, Dimitrov DS, Fry TJ. Preclinical development of flt3-redirected chimeric antigen receptor T cell immunotherapy for acute myeloid leukemia. Blood 2016; 128(22): 1072

[50] Wang Y, Xu Y, Li S, Liu J, Xing Y, Xing H, Tian Z, Tang K, Rao Q, Wang M, Wang J. Targeting FLT3 in acute myeloid leukemia using ligand-based chimeric antigen receptor-engineered T cells. J Hematol Oncol 2018; 11(1): 60

[51] Campana D, van Dongen JJ, Mehta A, Coustan-Smith E, Wolvers-Tettero IL, Ganeshaguru K, Janossy G. Stages of T-cell receptor protein expression in T-cell acute lymphoblastic leukemia. Blood 1991; 77(7): 1546–1554

[52] Campana D, Behm FG. Immunophenotyping of leukemia. J Immunol Methods 2000; 243(1-2): 59–75

[53] Tiftik N, Bolaman Z, Batun S, Ayyildiz O, Isikdogan A, Kadikoylu G, Muftuoglu E. The importance of CD7 and CD56 antigens in acute leukaemias. Int J Clin Pract 2004; 58(2): 149–152

[54] Miwa H, Nakase K, Kita K. Biological characteristics of CD7⁺ acute leukemia. Leuk Lymphoma 1996; 21(3-4): 239–244

[55] Gomes-Silva D, Atilla E, Atilla PA, Mo F, Tashiro H, Srinivasan M, Lulla P, Rouce RH, Cabral JMS, Ramos CA, Brenner MK, Mamonkin M. CD7 CAR T cells for the therapy of acute myeloid leukemia. Mol Ther 2019; 27(1): 272–280

[56] Bakker AB, van den Oudenrijn S, Bakker AQ, Feller N, van Meijer M, Bia JA, Jongeneelen MA, Visser TJ, Bijl N, Geuijen CA, Marissen WE, Radosevic K, Throsby M, Schuurhuis GJ, Ossenkoppele GJ, de Kruif J, Goudsmit J, Kruisbeek AM. C-type lectin-like molecule-1: a novel myeloid cell surface marker associated with acute myeloid leukemia. Cancer Res 2004; 64(22): 8443–8450

[57] Wang J, Chen S, Xiao W, Li W, Wang L, Yang S, Wang W, Xu L, Liao S, Liu W, Wang Y, Liu N, Zhang J, Xia X, Kang T, Chen G, Cai X, Yang H, Zhang X, Lu Y, Zhou P. CAR-T cells targeting CLL-1 as an approach to treat acute myeloid leukemia. J Hematol Oncol 2018; 11(1): 7

[58] Laborda E, Mazagova M, Shao S, Wang X, Quirino H, Woods AK, Hampton EN, Rodgers DT, Kim CH, Schultz PG, Young TS. Development of a chimeric antigen receptor targeting C-type lectin-like molecule-1 for human acute myeloid leukemia. Int J Mol Sci 2017; 18(11): E2259

[59] Kenderian SS, Habermann TM, Macon WR, Ristow KM, Ansell SM, Colgan JP, Johnston PB, Inwards DJ, Markovic SN, Micallef IN, Thompson CA, Porrata LF, Martenson JA, Witzig TE, Nowakowski GS. Large B-cell transformation in nodular lymphocyte-predominant Hodgkin lymphoma: 40-year experience from a single institution. Blood 2016; 127(16): 1960–1966

[60] Tashiro H, Sauer T, Shum T, Parikh K, Mamonkin M, Omer B, Rouce RH, Lulla P, Rooney CM, Gottschalk S, Brenner MK. Treatment of acute myeloid leukemia with T cells expressing chimeric antigen receptors directed to C-type lectin-like molecule 1. Mol Ther 2017; 25(9): 2202–2213

[61] Legras S, Günthert U, Stauder R, Curt F, Oliferenko S, Kluin-Nelemans HC, Marie JP, Proctor S, Jasmin C, Smadja-Joffe F. A strong expression of CD44-6v correlates with shorter survival of patients with acute myeloid leukemia. Blood 1998; 91(9): 3401–3413

[62] Casucci M, Nicolis di Robilant B, Falcone L, Camisa B, Norelli M, Genovese P, Gentner B, Gullotta F, Ponzoni M, Bernardi M, Marcatti M, Saudemont A, Bordignon C, Savoldo B, Ciceri F, Naldini L, Dotti G, Bonini C, Bondanza A. CD44v6-targeted T cells mediate potent antitumor effects against acute myeloid leukemia and multiple myeloma. Blood 2013; 122(20): 3461–3472

[63] Ross JF, Wang H, Behm FG, Mathew P, Wu M, Booth R, Ratnam M. Folate receptor type β is a neutrophilic lineage marker and is differentially expressed in myeloid leukemia. Cancer 1999; 85(2): 348–357

[64] Pan XQ, Zheng X, Shi G, Wang H, Ratnam M, Lee RJ. Strategy for the treatment of acute myelogenous leukemia based on folate receptor β-targeted liposomal doxorubicin combined with receptor induction using all-trans retinoic acid. Blood 2002; 100(2): 594–602

[65] Lynn RC, Poussin M, Kalota A, Feng Y, Low PS, Dimitrov DS, Powell DJ Jr. Targeting of folate receptor b on acute myeloid leukemia blasts with chimeric antigen receptor-expressing T cells. Blood 2015; 125(22): 3466–3476

[66] Lynn RC, Feng Y, Schutsky K, Poussin M, Kalota A, Dimitrov DS, Powell DJ Jr. High-affinity FRb-specific CAR T cells eradicate AML and normal myeloid lineage without HSC toxicity. Leukemia 2016; 30(6): 1355–1364

[67] Jiang H, Li C, Yin P, Guo T, Liu L, Xia L, Wu Y, Zhou F, Ai L, Shi W, Lu X, Wang H, Tang L, Wei Q, Deng J, Jin R, Xiong W, Dong J, Mei H, Hu Y. Anti-CD19 chimeric antigen receptor-modified T-cell therapy bridging to allogeneic hematopoietic stem cell transplantation for relapsed/refractory B-cell acute lymphoblastic leukemia: an open-label pragmatic clinical trial. Am J Hematol 2019; 94(10): 1113–1122

[68] Park JH, Rivière I, Gonen M, Wang X, Sénéchal B, Curran KJ, Sauter C, Wang Y, Santomasso B, Mead E, Roshal M, Maslak P, Davila M, Brentjens RJ, Sadelain M. Long-term follow-up of CD19 CAR therapy in acute lymphoblastic leukemia. N Engl J Med 2018; 378(5): 449–459

[69] Zhu YM, Wu Z, Tan YP, Du YY, Liu Z, Ou RM, Liu S, Pu CF, Jiang J, Wang JP, Xiao L, Zhang Q. Anti-CD19 chimeric antigen receptor T-cell therapy for adult Philadelphia chromosome-positive acute lymphoblastic leukemia: two case reports. Medicine (Baltimore) 2016; 95(51): e5676

[70] Maude SL, Laetsch TW, Buechner J, Rives S, Boyer M, Bittencourt H, Bader P, Verneris MR, Stefanski HE, Myers GD, Qayed M, De Moerloose B, Hiramatsu H, Schlis K, Davis KL, Martin PL, Nemecek ER, Yanik GA, Peters C, Baruchel A, Boissel N, Mechinaud F, Balduzzi A, Krueger J, June CH, Levine BL, Wood P, Taran T, Leung M, Mueller KT, Zhang Y, Sen K, Lebwohl D, Pulsipher MA, Grupp SA. Tisagenlecleucel in children and young adults with B-cell lymphoblastic leukemia. N Engl J Med 2018; 378(5): 439–448

RIGHTS & PERMISSIONS

The Author(s) 2020. This article is published with open access at link.springer.com and journal.hep.com.cn