Targeting immune checkpoint B7-H6 in cancer immunotherapy

Authors

DOI:

https://doi.org/10.66505/cbtt.v1i3.55

Keywords:

B7-H6, NKp30, natural killer cells, tumor immunosurveillance, immune escape, soluble B7-H6, cancer immunotherapy, cellular immunotherapy

Abstract

Natural killer (NK) cells are central mediators of antitumor immunity and possess the unique ability to recognize and eliminate malignant cells independently of major histocompatibility complex (MHC) restriction. Compared with T-cell-based approaches, NK-cell immunotherapies generally exhibit a more favorable safety profile, highlighting their growing therapeutic potential in oncology. Among the ligands that regulate NK-cell activity, B7-H6 has emerged as a particularly attractive target because of its highly restricted expression in normal tissues and frequent upregulation across diverse malignancies. Initially identified as a ligand for the activating NK-cell receptor NKp30, B7-H6 is now recognized as a multifunctional molecule with roles extending beyond immune recognition. Accumulating preclinical evidence suggests that B7-H6 may contribute to tumor progression by regulating signaling pathways involved in proliferation, survival, migration, invasion, and immune evasion. Furthermore, the existence of soluble B7-H6 adds an additional layer of biological complexity and may influence both NK-cell function and therapeutic responsiveness. In this review, we summarize current knowledge regarding the regulation, expression patterns, and biological functions of B7-H6, with particular emphasis on its dual roles in tumor immunology and cancer cell biology. We discuss the emerging significance of soluble B7-H6, evaluate the current landscape of B7-H6-targeted therapeutic strategies, including bispecific engagers and cellular immunotherapies, and highlight key translational challenges that may influence clinical development. Collectively, current findings position B7-H6 as a promising immuno-oncologic target at the intersection of immune surveillance, immune escape, and malignant progression, warranting continued investigation as a next-generation therapeutic axis in cancer immunotherapy.

References

1. Barrow AD, Martin CJ, Colonna M. The natural cytotoxicity receptors in health and disease. Front Immunol. 2019;10:909. doi:10.3389/fimmu.2019.00909

2. Laskowski TJ, Biederstädt A, Rezvani K. Natural killer cells in antitumour adoptive cell immunotherapy. Nat Rev Cancer. 2022;22(10):557-575. doi:10.1038/s41568-022-00491-0

3. Dhatchinamoorthy K, Colbert JD, Rock KL. Cancer immune evasion through loss of MHC class I antigen presentation. Front Immunol. 2021;12:636568. doi:10.3389/fimmu.2021.636568

4. Correia AL, Guimaraes JC, Auf der Maur P, De Silva D, Trefny MP, Okamoto R, et al. Hepatic stellate cells suppress NK cell-sustained breast cancer dormancy. Nature. 2021;594(7864):566-571. doi:10.1038/s41586-021-03614-z

5. Liu X, Song J, Zhang H, Liu X, Zuo F, Zhao Y, et al. Immune checkpoint HLA-E:CD94-NKG2A mediates evasion of circulating tumor cells from NK cell surveillance. Cancer Cell. 2023;41(2):272-287.e9. doi:10.1016/j.ccell.2023.01.001

6. Simonetta F, Alvarez M, Negrin RS. Natural killer cells in graft-versus-host-disease after allogeneic hematopoietic cell transplantation. Front Immunol. 2017;8:465. doi:10.3389/fimmu.2017.00465

7. Huang S, Xing F, Dai Y, Zhang Z, Zhou G, Yang S, et al. Navigating chimeric antigen receptor-engineered natural killer cells as drug carriers via three-dimensional mapping of the tumor microenvironment. J Control Release. 2023;362:524-535. doi:10.1016/j.jconrel.2023.09.007

8. Poli A, Michel T, Thérésine M, Andrès E, Hentges F, Zimmer J. CD56bright natural killer (NK) cells: an important NK cell subset. Immunology. 2009;126(4):458-465. doi:10.1111/j.1365-2567.2008.03027.x

9. Seymour F, Cavenagh JD, Mathews J, Gribben JG. NK cells CD56bright and CD56dim subset cytokine loss and exhaustion is associated with impaired survival in myeloma. Blood Adv. 2022;6(17):5152-5159. doi:10.1182/bloodadvances.2022007905

10. Weber S, Menees KB, Park J, Agin-Liebes J, Lin CC, Alcalay RN, et al. Distinctive CD56dim NK subset profiles and increased NKG2D expression in blood NK cells of Parkinson's disease patients. NPJ Parkinsons Dis. 2024;10(1):36. doi:10.1038/s41531-024-00652-y

11. Myers JA, Miller JS. Exploring the NK cell platform for cancer immunotherapy. Nat Rev Clin Oncol. 2021;18(2):85-100. doi:10.1038/s41571-020-0426-7

12. Albertsson PA, Basse PH, Hokland M, Goldfarb RH, Nagelkerke JF, Nannmark U, et al. NK cells and the tumour microenvironment: implications for NK-cell function and anti-tumour activity. Trends Immunol. 2003;24(11):603-609. doi:10.1016/j.it.2003.09.007

13. Mandal R, Şenbabaoğlu Y, Desrichard A, Havel JJ, Dalin MG, Riaz N, et al. The head and neck cancer immune landscape and its immunotherapeutic implications. JCI Insight. 2016;1(17):e89829. doi:10.1172/jci.insight.89829

14. Ljunggren HG, Kärre K. In search of the ‘missing self’: MHC molecules and NK cell recognition. Immunol Today. 1990;11(7):237-244. doi:10.1016/0167-5699(90)90097-s

15. Chen S, Zhu H, Jounaidi Y. Comprehensive snapshots of natural killer cell functions, signaling, molecular mechanisms and clinical utilization. Signal Transduct Target Ther. 2024;9(1):302. doi:10.1038/s41392-024-02005-w

16. Letafati A, Salahi Ardekani O, Naderisemiromi M, Norouzi M, Shafiei M, Nik S, et al. Unraveling the dynamic mechanisms of natural killer cells in viral infections: insights and implications. Virol J. 2024;21(1):18. doi:10.1186/s12985-024-02287-0

17. Sivori S, Della Chiesa M, Carlomagno S, Quatrini L, Munari E, Vacca P, et al. Inhibitory receptors and checkpoints in human NK cells, implications for the immunotherapy of cancer. Front Immunol. 2020;11:2156. doi:10.3389/fimmu.2020.02156

18. Bryceson YT, March ME, Ljunggren HG, Long EO. Activation, coactivation, and costimulation of resting human natural killer cells. Immunol Rev. 2006;214:73-91. doi:10.1111/j.1600-065x.2006.00457.x

19. Getahun A, Cambier JC. Of ITIMs, ITAMs, and ITAMis: revisiting immunoglobulin Fc receptor signaling. Immunol Rev. 2015;268(1):66-73. doi:10.1111/imr.12336

20. Butcher S, Arney KL, Cook GP. MAFA-L, an ITIM-containing receptor encoded by the human NK cell gene complex and expressed by basophils and NK cells. Eur J Immunol. 1998;28(11):3755-3762. doi:10.1002/(sici)1521-4141(199811)28:11<3755::AID-IMMU3755>3.0.CO;2-3

21. Zhang Y, Chen S, Tang X, Peng Y, Jiang T, Zhang X, et al. The role of KLRG1: a novel biomarker and new therapeutic target. Cell Commun Signal. 2024;22(1):337. doi:10.1186/s12964-024-01714-7

22. Aldemir H, Prod’homme V, Dumaurier MJ, Retiere C, Poupon G, Cazareth J, et al. Cutting edge: lectin-like transcript 1 is a ligand for the CD161 receptor. J Immunol. 2005;175(12):7791-7795. doi:10.4049/jimmunol.175.12.7791

23. Mathewson ND, Ashenberg O, Tirosh I, Gritsch S, Perez EM, Marx S, et al. Inhibitory CD161 receptor identified in glioma-infiltrating T cells by single-cell analysis. Cell. 2021;184(5):1281-1298.e26. doi:10.1016/j.cell.2021.01.022

24. Cantoni C, Bottino C, Augugliaro R, Morelli L, Marcenaro E, Castriconi R, et al. Molecular and functional characterization of IRp60, a member of the immunoglobulin superfamily that functions as an inhibitory receptor in human NK cells. Eur J Immunol. 1999;29(10):3148-3159. doi:10.1002/(SICI)1521-4141(199910)29:10<3148::AID-IMMU3148>3.0.CO;2-L

25. Mace EM. Human natural killer cells: form, function, and development. J Allergy Clin Immunol. 2023;151(2):371-385. doi:10.1016/j.jaci.2022.09.022

26. Demaria O, Gauthier L, Debroas G, Vivier E. Natural killer cell engagers in cancer immunotherapy: Next generation of immuno-oncology treatments. Eur J Immunol. 2021;51(8):1934-1942. doi:10.1002/eji.202048953

27. Perussia B, Trinchieri G, Jackson A, Warner NL, Faust J, Rumpold H, et al. The Fc receptor for IgG on human natural killer cells: phenotypic, functional, and comparative studies with monoclonal antibodies. J Immunol. 1984;133(1):180-189. doi:10.4049/jimmunol.133.1.180

28. Zhou G, Zhang Y, Gu Y, Cao B, Fan X, Yu D, et al. Enhanced antibody-mediated cellular cytotoxicity of germline-like anti-HER2 antibodies through a point mutation in complementarity-determining regions. J Immunol. 2025;214(7):1849-1859. doi:10.1093/jimmun/vkaf063

29. Bachanova V, Sarhan D, DeFor TE, Cooley S, Panoskaltsis-Mortari A, Blazar BR, et al. Haploidentical natural killer cells induce remissions in non-Hodgkin lymphoma patients with low levels of immune-suppressor cells. Cancer Immunol Immunother. 2018;67(3):483-494. doi:10.1007/s00262-017-2100-1

30. Gauthier L, Morel A, Anceriz N, Rossi B, Blanchard-Alvarez A, Grondin G, et al. Multifunctional natural killer cell engagers targeting NKp46 trigger protective tumor immunity. Cell. 2019;177(7):1701-1713.e16. doi:10.1016/j.cell.2019.04.041

31. Qian S, Zhou Y, Jin Z, Li X, Tian Y, Chen F, et al. Advancements in the study of the immune molecule NKp46 in immune system-related diseases. Clin Rev Allergy Immunol. 2024;67(1-3):96-110. doi:10.1007/s12016-024-09010-5

32. Cerwenka A, Lanier LL. NKG2D ligands: unconventional MHC class I-like molecules exploited by viruses and cancer. Tissue Antigens. 2003;61(5):335-343. doi:10.1034/j.1399-0039.2003.00070.x

33. Tang J, Lu Y, Chen M, Wu Q, Li Y, Qin Y, et al. The metabolic regulation of the NKG2D-positive NK and T cells and their role in disease progression. Biomolecules. 2025;15(11):1506. doi:10.3390/biom15111506

34. Segovis CM, Schoon RA, Dick CJ, Nacusi LP, Leibson PJ, Billadeau DD. PI3K Links NKG2D signaling to a CrkL pathway involved in natural killer cell adhesion, polarity, and granule secretion. J Immunol. 2009;182(11):6933-6942. doi:10.4049/jimmunol.0803840

35. Boneva E, Shivarov V, Ivanova M. A concise review of the role of the NKG2D receptor and its ligands in cancer. Immuno. 2025;5(1):9. doi:10.3390/immuno5010009

36. Joyce MG, Paul T, Zhuravleva MA, Jaw J, Colonna M, Sun PD. Crystal structure of human natural cytotoxicity receptor NKp30 and identification of its ligand binding site. Proc Natl Acad Sci U S A. 2011;108(15):6223-6228. doi:10.1073/pnas.1100622108

37. Brandt CS, Baratin M, Yi EC, Kennedy J, Gao Z, Fox B, et al. The B7 family member B7-H6 is a tumor cell ligand for the activating natural killer cell receptor NKp30 in humans. J Exp Med. 2009;206(7):1495-1503. doi:10.1084/jem.20090681

38. Li Y, Wang Q, Mariuzza RA. Structure of the human activating natural cytotoxicity receptor NKp30 bound to its tumor cell ligand B7-H6. J Exp Med. 2011;208(4):703-714. doi:10.1084/jem.20102548

39. Chen Y, Mo J, Jia X, He Y. The B7 family member B7-H6: a new bane of tumor. Pathol Oncol Res. 2018;24(4):717-721. doi:10.1007/s12253-017-0357-5

40. Xu Z, Shen J, Wang MH, Yi T, Yu Y, Zhu Y, et al. Comprehensive molecular profiling of the B7 family of immune-regulatory ligands in breast cancer. Oncoimmunology. 2016;5(8):e1207841. doi:10.1080/2162402X.2016.1207841

41. Ni L, Dong C. New B7 family checkpoints in human cancers. Mol Cancer Ther. 2017;16(7):1203-1211. doi:10.1158/1535-7163.MCT-16-0761

42. Hu Y, Zeng T, Xiao Z, Hu Q, Li Y, Tan X, et al. Immunological role and underlying mechanisms of B7-H6 in tumorigenesis. Clin Chim Acta. 2020;502:191-198. doi:10.1016/j.cca.2019.12.030

43. Matta J, Baratin M, Chiche L, Forel JM, Cognet C, Thomas G, et al. Induction of B7-H6, a ligand for the natural killer cell-activating receptor NKp30, in inflammatory conditions. Blood. 2013;122(3):394-404. doi:10.1182/blood-2013-01-481705

44. Schlecker E, Fiegler N, Arnold A, Altevogt P, Rose-John S, Moldenhauer G, et al. Metalloprotease-mediated tumor cell shedding of B7-H6, the ligand of the natural killer cell-activating receptor NKp30. Cancer Res. 2014;74(13):3429-3440. doi:10.1158/0008-5472.CAN-13-3017

45. Gutierrez-Franco J, Hernandez-Gutierrez R, Bueno-Topete MR, Haramati J, Navarro-Hernandez RE, Escarra-Senmarti M, et al. Characterization of B7H6, an endogenous ligand for the NK cell activating receptor NKp30, reveals the identity of two different soluble isoforms during normal human pregnancy. Immunobiology. 2018;223(1):57-63. doi:10.1016/j.imbio.2017.10.012

46. Fiegler N, Textor S, Arnold A, Rolle A, Köppel J, Witzens-Harig M, et al. Downregulation of the activating NKp30 ligand B7-H6 by HDAC inhibitors impairs tumor cell recognition by NK cells. Blood. 2013;122(5):684-693. doi:10.1182/blood-2013-02-482513

47. Lee S, Kim JH, Jang IH, Jo S, Lee SY, Oh SC, et al. Harnessing B7-H6 for anticancer immunotherapy: expression, pathways, and therapeutic strategies. Int J Mol Sci. 2024;25(19):10326. doi:10.3390/ijms251910326

48. Mohammadi A, Najafi S, Amini M, Mansoori B, Baghbanzadeh A, Hoheisel JD, et al. The potential of B7-H6 as a therapeutic target in cancer immunotherapy. Life Sci. 2022;304:120709. doi:10.1016/j.lfs.2022.120709

49. Pesce S, Tabellini G, Cantoni C, Patrizi O, Coltrini D, Rampinelli F, et al. B7-H6-mediated downregulation of NKp30 in NK cells contributes to ovarian carcinoma immune escape. Oncoimmunology. 2015;4(4):e1001224. doi:10.1080/2162402X.2014.1001224

50. Banu N, Riera-Leal A, Haramati J, Ortiz-Lazareno PC, Panikar SS, Bastidas-Ramirez BE, et al. B7-H6, an immunoligand for the natural killer cell activating receptor NKp30, reveals inhibitory effects on cell proliferation and migration, but not apoptosis, in cervical cancer derived-cell lines. BMC Cancer. 2020;20(1):1083. doi:10.1186/s12885-020-07608-4

51. Chen L, Feng J, Xu B, Zhou Y, Zheng X, Wu C, et al. B7-H6 expression in human hepatocellular carcinoma and its clinical significance. Cancer Cell Int. 2018;18:126. doi:10.1186/s12935-018-0627-7

52. Yang S, Yuan L, Wang Y, Zhu M, Wang J, Ke X. B7-H6 promotes cell proliferation, migration and invasion of non-Hodgkin lymphoma via Ras/MEK/ERK pathway based on quantitative phosphoproteomics data. Onco Targets Ther. 2020;13:5795-5805. doi:10.2147/OTT.S257512

53. Fan J, Wang Y, Liang X, Peng Y, Li S, Li X, et al. B7-H6 enhances F-actin rearrangement by targeting c-MYC activation to promote medulloblastoma migration and invasion. Med Oncol. 2023;40(3):85. doi:10.1007/s12032-023-01947-5

54. Zhang B, Sun J, Yao X, Li J, Tu Y, Yao F, et al. Knockdown of B7H6 inhibits tumor progression in triple-negative breast cancer. Oncol Lett. 2018;16(1):91-96. doi:10.3892/ol.2018.8689

55. Cao G, Wang J, Zheng X, Wei H, Tian Z, Sun R. Tumor therapeutics work as stress inducers to enhance tumor sensitivity to natural killer (NK) cell cytolysis by up-regulating NKp30 ligand B7-H6. J Biol Chem. 2015;290(50):29964-29973. doi:10.1074/jbc.M115.674010

56. Li YM, Liu ZY, Li ZC, Wang JC, Yu JM, Yang HJ, et al. Alterations of the immunologic co-stimulator B7 and TNFR families correlate with hepatocellular carcinoma prognosis and metastasis by inactivating STAT3. Int J Mol Sci. 2019;20(1):156. doi:10.3390/ijms20010156

57. Che F, Xie X, Wang L, Su Q, Jia F, Ye Y, et al. B7-H6 expression is induced by lipopolysaccharide and facilitates cancer invasion and metastasis in human gliomas. Int Immunopharmacol. 2018;59:318-327. doi:10.1016/j.intimp.2018.03.020

58. Zhou Y, Xu Y, Chen L, Xu B, Wu C, Jiang J. B7-H6 expression correlates with cancer progression and patient’s survival in human ovarian cancer. Int J Clin Exp Pathol. 2015;8(8):9428-9433. PMID: 26464699

59. Zhang X, Zhang G, Qin Y, Bai R, Huang J. B7-H6 expression in non-small cell lung cancers. Int J Clin Exp Pathol. 2014;7(10):6936-6942. PMID: 25400778

60. Qiu H, Gao S, Sun Z, Wang J. Dual role of B7-H6 as a novel prognostic marker in hepatocellular carcinoma. APMIS. 2021;129(3):105-117. doi:10.1111/apm.13099

61. Semeraro M, Rusakiewicz S, Minard-Colin V, Delahaye NF, Enot D, Vély F, et al. Clinical impact of the NKp30/B7-H6 axis in high-risk neuroblastoma patients. Sci Transl Med. 2015;7(283):283ra55. doi:10.1126/scitranslmed.aaa2327

62. Jin Y, Wang X, Kong W, Li X. Association between elevated serum soluble B7-H6 and infection in hemodialysis patients. Clin Exp Nephrol. 2025;29(10):1476-1483. doi:10.1007/s10157-025-02705-9

63. Phillips M, Romeo F, Bitsaktsis C, Sabatino D. B7H6-derived peptides trigger TNF-α-dependent immunostimulatory activity of lymphocytic NK92-MI cells. Peptide Science. 2016;106(5):658-672. doi:10.1002/bip.22879

64. Pekar L, Klausz K, Busch M, Valldorf B, Kolmar H, Wesch D, et al. Affinity maturation of B7-H6 translates into enhanced NK cell-mediated tumor cell lysis and improved proinflammatory cytokine release of bispecific immunoligands via NKp30 engagement. J Immunol. 2021;206(1):225-236. doi:10.4049/jimmunol.2001004

65. Peipp M, Derer S, Lohse S, Staudinger M, Klausz K, Valerius T, et al. HER2-specific immunoligands engaging NKp30 or NKp80 trigger NK-cell-mediated lysis of tumor cells and enhance antibody-dependent cell-mediated cytotoxicity. Oncotarget. 2015;6(31):32075-32088. doi:10.18632/oncotarget.5135

66. Wu MR, Zhang T, Gacerez AT, Coupet TA, DeMars LR, Sentman CL. B7H6-specific bispecific T cell engagers lead to tumor elimination and host antitumor immunity. J Immunol. 2015;194(11):5305-5311. doi:10.4049/jimmunol.1402517

67. Wu MR, Zhang T, DeMars LR, Sentman CL. B7H6-specific chimeric antigen receptors lead to tumor elimination and host antitumor immunity. Gene Ther. 2015;22(8):675-684. doi:10.1038/gt.2015.29

68. Choi Y, Hua C, Sentman CL, Ackerman ME, Bailey-Kellogg C. Antibody humanization by structure-based computational protein design. MAbs. 2015;7(6):1045-1057. doi:10.1080/19420862.2015.1076600

69. Hua CK, Gacerez AT, Sentman CL, Ackerman ME. Development of unique cytotoxic chimeric antigen receptors based on human scFv targeting B7H6. Protein Eng Des Sel. 2017;30(10):713-721. doi:10.1093/protein/gzx051

70. Zhang H, Xia L, Xuzhang W, Li Z, Zhang J, Li F, et al. BCL-2 mutant B7H6-CAR-T cells synergized with venetoclax for treating small cell lung cancer. J Immunother Cancer. 2025;13(5):e010073. doi:10.1136/jitc-2024-010073

71. Ma X, He H, Zhu Y, Zuo D, Wang F, Feng M, et al. Dual T/NK cell engagement via B7-H6-targeted bispecific antibodies and IL-15 eradicates chemo-resistant solid tumors. Front Immunol. 2025;16:1625813. doi:10.3389/fimmu.2025.1625813

72. Kilian M, Friedrich MJ, Lu KH-N, Vonhören D, Jansky S, Michel J, et al. The immunoglobulin superfamily ligand B7H6 subjects T cell responses to NK cell surveillance. Sci Immunol. 2024;9(95):eadj7970. doi:10.1126/sciimmunol.adj7970

73. Zhang W, Auguste A, Liao X, Walterskirchen C, Bauer K, Lin YH, et al. A novel B7-H6-targeted IgG-like T cell-engaging antibody for the treatment of gastrointestinal tumors. Clin Cancer Res. 2022;28(23):5190-5201. doi:10.1158/1078-0432.CCR-22-2108

Diagram showing activating and inhibitory receptor–ligand interactions between natural killer (NK) cells and target cells, illustrating downstream signaling pathways that regulate NK-cell cytotoxicity and cytokine release

Published

2026-08-12

How to Cite

1.
Yang Z, Zhao Q. Targeting immune checkpoint B7-H6 in cancer immunotherapy. Cancer Biome Target Ther. [Internet]. 2026 Aug. 12 [cited 2026 Oct. 2];1(3):168-87. Available from: https://cancerbiometherapy.com/index.php/cbtt/article/view/55

Issue

Section

Review

Funding data