HDAC6 orchestrates NK cell maturation and antitumor immunity

Wenwen Yang; Panpan Tian; Xiaowei Guo; Miaomiao Ding; Rong Xiao; Zhuanchang Wu; Xuetian Yue; Chunyang Li; Lifen Gao; Jun Zhou; Chun-hong Ma; Xueen Li; Jianping Wang; Xiaohong Liang

doi:10.1136/jitc-2026-015167

. 2026 Jul 27;14(7):e015167. doi: 10.1136/jitc-2026-015167

HDAC6 orchestrates NK cell maturation and antitumor immunity

Wenwen Yang ^1,⁰, Panpan Tian ^1,^2,^*,⁰, Xiaowei Guo ¹, Miaomiao Ding ¹, Rong Xiao ³, Zhuanchang Wu ^1,⁴, Xuetian Yue ⁵, Chunyang Li ⁶, Lifen Gao ^1,⁴, Jun Zhou ⁷, Chun-hong Ma ^1,^4,⁸, Xueen Li ^9,^*, Jianping Wang ^10,^*, Xiaohong Liang ^1,^4,^✉

¹Key Laboratory for Experimental Teratology of Ministry of Education, Key Laboratory of Infection and Immunity of Shandong Province and Department of Immunology, School of Basic Medical Sciences, Cheeloo Medical College, Shandong University, Jinan, Shandong, China

²Department of Clinical Laboratory, the Affiliated Hospital of Nanjing University Medical School, Nanjing University, Nanjing Drum Tower Hospital, Nanjing, Jiangsu, China

³Department of Radiation Oncology and Shandong Provincial Key Laboratory of Precision Oncology, Shandong First Medical University，Shandong Academy of Medical Sciences, Jinan, Shandong, China

⁴Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities, Shandong University, Jinan, Shandong, China

⁵Department of Cellular Biology，School of Basic Medical Sciences, Shandong University, Jinan, Shandong, China

⁶Key Laboratory for Experimental Teratology of Ministry of Education, Department of Histology and Embryology, School of Basic Medical Science, Shandong University, Jinan, Shandong, China

⁷Institute of Biomedical Sciences, Shandong Provincial Key Laboratory of Animal Resistance Biology, Collaborative Innovation Center of Cell Biology in Universities of Shandong, College of Life Sciences, Shandong Normal University, Jinan, Shandong, China

⁸State Key Laboratory of Reproductive Medicine and Offspring Health, Shandong University, Jinan, Shandong, China

⁹Department of Neurosurgery, Qilu Hospital of Shandong University, Jinan, Shandong, China

¹⁰Department of Liver Transplantation and Hepatobiliary Surgery, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China

Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.

Additional supplemental material is published online only. To view, please visit the journal online (https://doi.org/10.1136/jitc-2026-015167).

None declared.

^✉

Professor Xiaohong Liang; liangxiaohong@email.sdu.edu.cn

Dr Jianping Wang; jianpingwang@email.sdfmu.edu.cn

Professor Xueen Li; qlneurolab@163.com

Dr Panpan Tian; njdthpp@163.com

⁰

WY and PT contributed equally.

PMCID: PMC13409089 PMID: 42508828

Abstract

Background

Natural killer (NK) cells act as the host’s first line of immunosurveillance, and their maturation and effector functions are finely regulated by multiple factors. Although histone deacetylase (HDAC) inhibition has been reported to impair NK cell viability and/or antitumor effects, the specific HDAC member involved and the underlying mechanisms remain unclear.

Methods

We analyzed the expression of HDAC family members during NK cell activation and in tumor-infiltrating NK cells. Genetic approaches, including Hdac6 knockout, knockdown, and overexpression, were used to evaluate its role in NK cell proliferation, maturation, and effector function. Mechanistic studies examined protein acetylation status, chaperone activity, and IL-15–STAT5 signaling. Functional relevance was assessed using NK cell adoptive transfer models and interleukin (IL)-15 combination treatment in tumor settings.

Results

HDAC6 was the most significantly upregulated HDAC member on NK cell activation, whereas its expression was reduced in tumor-infiltrating NK cells and correlated with poor patient survival. Hdac6 deficiency markedly impaired NK cell proliferation, maturation, and effector functions, while Hdac6 overexpression showed a promoting effect. Mechanistically, loss of Hdac6 led to the hyperacetylation of HSP90, which in turn destroyed its chaperone activity for phosphorylated STAT5 and blocked the transduction of the IL-15 signaling pathway indispensable for NK cell maturation and effector function. Translationally, HDAC6 overexpression not only obviously improved tumor suppression of transferred NK cells, but also synergized with IL-15 treatment to further boost NK cell antitumor efficacy.

Conclusion

HDAC6 was identified as a critical regulator of NK cell biology through strengthening the IL-15/STAT5 pathway and may serve as a potential target for improving NK cell function.

Keywords: Natural killer - NK

WHAT IS ALREADY KNOWN ON THIS TOPIC

Natural killer (NK) cells are critical mediators of tumor immunosurveillance, but their maturation and effector functions are frequently impaired within the tumor microenvironment. Although histone deacetylases (HDACs) inhibition has been implicated in NK cell biology, the specific roles and underlying mechanisms of individual HDAC family members remain incompletely understood.

WHAT THIS STUDY ADDS

HDAC6 was prominently upregulated during NK cell activation, whereas it was reduced in tumor-infiltrating NK cells correlating with poor patient survival. Functionally, HDAC6 promotes NK cell maturation, proliferation, and effector activities by enhancing HSP90 deacetylation and facilitating HSP90-STAT5 signaling, thereby supporting interleukin (IL)-15-driven NK cell maturation.

HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY

These findings identify HDAC6 as a critical regulator of NK cell homeostasis and antitumor immunity and provide a mechanistic rationale for engineering NK cells in cancer immunotherapies.

Introduction

Natural killer (NK) cells are crucial immune cells for tumor immunosurveillance.¹ Distinct from T cells, NK cells are activated without specific antigen recognition and class I major histocompatibility complex restriction. On activation, NK cells can directly eliminate the transformed cells through releasing perforin and granzymes or the expression of death ligands (FasL, TRAIL, etc), and also recruit or activate additional immune subpopulations by producing cytokines, including interferon (IFN)-γ and tumor-necrosis factor (TNF)-α.² However, the hostile tumor microenvironment frequently reduces NK cell number and subverts their effector functions. Specifically, tumor-infiltrating NK cells (TINKs) showed decreased activating receptors and maturation markers, increased inhibitory receptors and impaired cytokine production and cytotoxic activities.^3
4 Thus, although the adoptive transfer of NK cells represents an ideal approach for cancer immunotherapy,⁵ its therapeutic efficacy still needs to be further improved through a better understanding of NK cell biology.

In mice, NK cells develop in the bone marrow (BM) from hematopoietic stem cells that sequentially differentiate into common lymphoid progenitors (CLPs) and NK lineage-restricted progenitors (NKPs).^6
7 After acquiring NK cell-specific markers, NK cells further differentiate from the immature stage into fully mature NK cells in a sequential order, as follows: CD27⁻CD11b⁻ → CD27⁺CD11b⁻ → CD27⁺CD11b⁺ → CD27⁻CD11b⁺.^8
9 Furthermore, killer cell lectin-like receptor G1 (KLRG1) is a well-established marker of terminally differentiated NK cells and its upregulation correlates with NK cell maturation.¹⁰ This development program parallels a progressive acquisition of effector function. Interleukin (IL)-15 is recognized as the critical cytokine for both the lineage commitment and terminal maturation of NK cells, processes that are initiated by diverse extracellular signals, including various cytokines.¹¹ Ultimately, NK cell lineage specification and maturation depend on intrinsic programming by a series of transcription factors such as Tbx21, Eomes and ZHX2.^12
13 Collectively, these findings indicate that the functional optimization of NK cells is underpinned by a precisely orchestrated developmental and maturation process.

Acetylation, serving as a crucial post-translational modification, regulates protein subcellular localization, interactions, stability, and functional activities, thus participating in numerous biological processes. Histone deacetylases (HDACs) are enzymes responsible for the deacetylation of histone and non-histone proteins, consisting of Zn²⁺-dependent HDACs (class I (HDAC1, HDAC2, HDAC3, HDAC8), class IIa (HDAC4, HDAC5, HDAC7, HDAC9), class IIb (HDAC6, HDAC10), and class IV (HDAC11)) and NAD⁺-dependent sirtuins (SIRT1-7).¹⁴ Emerging evidence indicates that inhibitors for Zn²⁺-dependent HDACs, trichostatin A (TSA), valproic acid, and sodium butyrate, impair NK cell viability and/or antitumor effects,^15–17 indicating that HDACs play roles in regulating NK cell homeostasis and functions. However, the detailed molecular mechanisms still remain obscure.

In the present study, we identified that, among Zn²⁺-dependent HDAC members, HDAC6 was most significantly upregulated during NK cell activation, while it was reduced in TINK cells. Moreover, in patients with high NK cell infiltration, elevated HDAC6 expression correlates with prolonged overall survival. Functionally, Hdac6 deficiency retarded NK cell maturation and inhibited its proliferation and effector functions in a cell-intrinsic manner. Mechanically, HDAC6 promoted HSP90 deacetylation and its interaction with p-STAT5, which in turn enhanced the IL-15 signaling pathway and improved NK cell functional maturation. From a translational perspective, HDAC6 overexpression in NK cells significantly improved their antitumor efficacy. Our study uncovers a new regulatory mechanism of NK cell homeostasis and functional maturation, highlighting the importance of protein acetylation in NK cell biology.

Results

Reduced HDAC6 expression in TINK cells correlates with poor patient survival

To assess whether HDACs are involved in regulating NK cells, we used the broad-spectrum inhibitors TSA (Trichostatin A) and SAHA (Suberoylanilide hydroxamic acid). Their effects on NK cell proliferation and functionality were subsequently evaluated. It was found that both TSA and SAHA dose-dependently suppressed NK cell proliferation (online supplemental figure S1A,B), as well as cytokine production and granule releasing ability (online supplemental figure S1C,D). In order to identify which HDAC family members might regulate NK cell function, we first assessed changes in HDAC expression profiles in NK-92 cells following stimulation with IL-12 and IL-15. Strikingly, among members of the HDAC family, HDAC6 messenger RNA (mRNA) level was significantly upregulated in NK-92 cells following stimulation with IL-12 and IL-15 (figure 1A). Furthermore, reverse transcription-quantitative PCR (RT-qPCR) and western blotting analysis showed the time-dependent upregulation of HDAC6 in activated NK cells (figure 1B,C). In addition, increased expression of HDAC6 was also detected in NK cells both at the mRNA and protein level under stimulation with poly(I:C) and anti-NKG2D agonistic antibody (figure 1D,E). On the contrary, NK92 cells treated with conditioned medium from HepG2 cells displayed the reduction of HDAC6 mRNA and protein expression (figure 1F). Correspondingly, flow cytometry analysis showed the reduced HDAC6 expression in TINK cells from patients with hepatocellular carcinoma (HCC) as compared with NK cells from paired para-cancerous tissues (figure 1G). Importantly, to further clarify the clinical relevance, we analyzed the correlation of HDACs expression in NK cells with patient survival using The Cancer Genome Atlas database. Results showed that among the HDAC family, only HDAC6 expression was significantly associated with better overall survival in patients with high NK cell infiltration (NCR1, a marker of NK cells), but not in patients with low NK cell infiltration (figure 1H and online supplemental figure S2). Overall, HDAC6 expression is upregulated on NK cell activation but is reduced in TINK cells, a decrease associated with poor HCC prognosis. This pattern suggests that HDAC6 acts as a novel regulator of NK cell functional status.

Loss of Hdac6 leads to reduced NK cell number and impaired proliferation

To further determine the impact of HDAC6 on NK cell homeostasis, we compared the number and frequency of NK cells from wild-type (WT) or Hdac6 knockout (KO) mice. We observed a significant reduction in both the frequency and absolute number of NK cells in peripheral blood (PB), spleen and liver from Hdac6 KO mice when compared with those from WT mice (figure 2A,B). However, there was no significant difference in the frequencies of CLP, pre-NKP and refined NKP (rNKP), which give rise to NK cells,^7
18 in BM between WT and Hdac6 KO mice (online supplemental figure S3A,B), indicating that HDAC6 has no obvious effect on NK cell development. To investigate whether HDAC6 influences NK cell homeostasis in a cell-intrinsic or extrinsic manner, we generated mixed BM chimera reconstituted with WT and Hdac6 KO cells (figure 2C). Briefly, congenic BM cells (CD45.1⁺ WT and CD45.2⁺Hdac6 KO) were transferred into irradiated NOD/ShiLtJGpt- Prkdc^em26cd52IL2rg^em26cd22/Gpt (NCG) recipients at the ratio of 1:1, and the relative proportion of CD3⁻NK1.1⁺ NK cells in the spleen of recipient mice was assessed 6 weeks after transfer. The superior reconstitution of the splenic NK cell compartment by CD45.1⁺ WT BM cells, compared with CD45.2⁺ Hdac6 KO BM cells (figure 2D), demonstrates that HDAC6 intrinsically supports NK cell maintenance.

The homeostasis of NK cells is dynamically determined by both proliferation and survival capability. We then investigated the proliferation and apoptosis of NK cells from WT and Hdac6 KO mice. Flow cytometry analysis showed that there was a lower level of Ki67 expression in both splenic and hepatic NK cells from Hdac6 deficient mice than those from WT mice (figure 2E), while they showed the comparable percentage of apoptosis (figure 2F). Corroborating the Ki67 data, EdU incorporation assays demonstrated a significant reduction in NK cell proliferative capacity on Hdac6 deletion (figure 2G,H). Consistently, HDAC6 knockdown significantly suppressed the proliferation of NK-92 cells (online supplemental figure S4A,B), while overexpression of HDAC6 had a promoting effect (online supplemental figure S4C,D). However, there was no significant effect on the apoptosis in NK-92 cells with HDAC6 overexpression or knockdown (online supplemental figure S4E,F). These data underline the importance of HDAC6 in NK cell homeostasis in a cell-intrinsic manner.

Hdac6 deficiency impairs NK cell maturation

After acquisition of NK cell lineage markers, NK cells are further induced to become phenotypically and functionally mature.⁷ We next assessed the influence of HDAC6 on the maturation process of NK cells. Intriguingly, Hdac6 deficiency led to a reduced proportion of CD27⁻CD11b⁺ mature NK cells, but increased CD27⁺CD11b⁻ NK cells in PB, liver and spleen (figure 3A,B). Consistently, the percentage of CD11b⁺KLRG1⁺ mature NK cells in spleen was significantly lower in Hdac6 KO mice than those in WT mice (figure 3C). Moreover, Klrg1 mRNA levels were also significantly downregulated in Hdac6 KO NK cells compared with WT controls (figure 3D). In addition, flow cytometry and RT-qPCR analyses revealed a significant downregulation of the key maturation transcription factors T-bet and Eomes in Hdac6-deficient NK cells compared with their WT counterparts (figure 3E,F). To investigate the cell-autonomous effect of HDAC6 on NK cell maturation, we detected KLRG1 expression in reconstituted NK cells from mixed BM chimera (as shown in figure 2C). We found that NK cells from mice transferred with Hdac6 KO BM cells showed lower levels of KLRG1 than those transferred with WT BM cells (figure 3G). Collectively, these results demonstrate that HDAC6 intrinsically promotes the terminal maturation of NK cells.

Loss of Hdac6 weakens the effector functions and antitumor activity of NK cells

NK cells acquire their optimal effector functions along with their maturation process.¹⁹ Thus, we determined the impact of Hdac6 deficiency on the functional activities of NK cells. It was found that under stimulation with IL-12 and IL-15, purified splenic NK cells from Hdac6 KO mice displayed markedly lower cytokine production (IFN-γ, TNF-α) and degranulation ability (indicated as surface CD107a level) than those from WT mice (figure 4A). Similar results were also observed in splenic, BM or peripheral NK cells from Hdac6 KO mice under stimulation with Yac-1 cells (figure 4B, online supplemental figure S5A,B). Consistently, purified NK cells from Hdac6 KO mice also showed significantly lower killing activities against Yac-1 cells than WT NK cells (figure 4C). Moreover, an in vivo killing assay against Yac-1 cells verified that NK cells in Hdac6 KO mice eliminated fewer Yac-1 cells (figure 4D). To examine the potential cell-autonomous role of HDAC6 in NK cell effector functions, we detected cytokine production and degranulation activity of NK cells in mixed BM chimera (as shown in figure 2C). Flow cytometry analysis showed that NK cells from Hdac6 KO BM cells had lower levels of IFN-γ and CD107a than those cells from WT BM cells (figure 4E). In addition, HDAC6 overexpression in NK-92 cells elevated the levels of IFN-γ, TNF-α and CD107a, and enhanced their cytotoxic activities against K562 cells; conversely, HDAC6 knockdown had an inhibitory effect (online supplemental figure S6A–D).

Considering the critical roles of NK cells in antitumor immunity, we then assessed the impact of Hdac6 deficiency in NK cells on tumor growth and metastasis. B16-F10 cells were subcutaneously implanted into C57BL/6 mice and splenic NK cells from WT or Hdac6 KO mice were intravenously transferred 5 days later (figure 4F). It was found that, compared with mice transferred with WT NK cells, mice with Hdac6 KO NK cells suffered from more severe tumor, manifested by increased tumor volume and weight (figure 4G). In addition, a melanoma lung metastasis model was established by intravenous injection of luciferase-expressing B16-F10 cells. Splenic NK cells from WT or Hdac6 KO mice were intravenously transferred 7 days later (figure 4H). In vivo imaging disclosed that mice receiving Hdac6 KO NK cells had higher tumor burden in lung than those with WT NK cell transfer (figure 4I). Consistently, mice transferred with Hdac6 KO NK cells showed shortened survival (figure 4J). Then, we wondered whether forced expression of HDAC6 could enhance antitumor efficacy of NK cells. Human HCC models were first established in NCG mice by implanting luciferase-expressing HepG2 cells (HepG2-luc). Subsequently, these tumor-bearing mice received adoptive transfers of NK-92 cells that had been infected with either an empty lentiviral vector (LV-empty) or a vector expressing HDAC6 (LV-HDAC6) (figure 4K, online supplemental figure S7). Results showed that transfer of LV-HDAC6 NK-92 cells significantly reduced the tumor burden of HepG2-luc bearing NCG mice when compared with those transferred with LV-empty-NK-92 cells (figure 4L). Moreover, the survival of tumor-bearing mice was significantly prolonged by the transfer of LV-HDAC6-expressing NK-92 cells (figure 4M). Altogether, these data demonstrate that HDAC6 facilitates NK cell cytotoxic activity and cytokine production, in turn suppressing tumor progression.

HDAC6 promotes HSP90 deacetylation and chaperone activity for phosphorylated STAT5 in NK cells

To further elucidate how HDAC6 regulates the maturation and function of NK cells, splenic NK cells from WT or Hdac6 KO mice were subjected to RNA sequencing. The KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment analysis revealed that, compared with WT NK cells, Hdac6 KO NK cells exhibited enrichment in pathways related to NK cell activation and receptor signaling (figure 5A). Notably, differentially expressed genes were enriched in the JAK-STAT signaling pathway. It is well established that JAK-STAT signaling, triggered by factors like IL-15, is essential for multiple aspects of NK cell biology, encompassing survival, maturation, and effector functions,^11
20 which aligns with the action of HDAC6 on NK cells. Interestingly, treatment with 20 ng/mL or 50 ng/mL IL-15 alone could also significantly upregulate Hdac6 expression in NK-92 cells (online supplemental figure S8), similar to the combination of IL-12 and IL-15. We then investigated whether HDAC6 affects NK cell homeostasis and functions through the IL-15-JAK-STAT signaling pathway. On IL-15 stimulation, Hdac6 deficient NK cells showed reduced IFN-γ and CD107a expression when compared with WT NK cells (figure 5B). IL-15 mediates its signaling through a receptor complex containing the common gamma chain (CD132) and the IL-15-specific beta chain (IL-15Rβ/CD122). Flow cytometry analysis displayed that there were no differences in the expression of CD122 and CD132 in NK cells between WT and Hdac6 deficient mice (figure 5C). However, the phosphorylation of STAT5, one of the important signaling events stimulated by IL-15, was significantly lower in Hdac6 KO NK cells than that in WT NK cells (figure 5D). Consistently, overexpression of HDAC6 upregulated, but HDAC6 knockdown decreased, the level of phosphorylated STAT5 in NK-92 cells (online supplemental figure S9A–C).

It was reported that STAT5 directly binds with and is a potential client protein of HSP90, whose chaperone activity depends on its deacetylation status.^21–23Therefore, we wondered whether HSP90 involves in the regulation of HDAC6 on STAT5 signaling and functions of NK cells. First, we found that IL-15 stimulation decreased the acetylated HSP90 (Ac-HSP90) level in NK cells (figure 5E). Then, we detected the interaction of STAT5 with HSP90. Immunoprecipitation assays showed that HSP90 interacted with p-STAT5 in IL-15 stimulated NK-92 cells (figure 5E). The co-localization of HSP90 and p-STAT5 in activated NK cells was also confirmed by confocal laser scanning microscopy analysis (figure 5F). Moreover, overexpression of HDAC6 in NK-92 cells downregulated the level of Ac-HSP90, but strengthened the interaction between HSP90 and p-STAT5 (figure 5G), while HDAC6 knockdown showed an opposite effect (figure 5H). Strikingly, treatment with 17-allylamino-17-demethoxygeldanamycin (17-AAG), a potent HSP90 inhibitor, markedly reduced p-STAT5 levels in NK cells by binding to HSP90 and disrupting its chaperone function (figure 5I). Moreover, 17-AAG abrogated the differences of p-STAT5 levels between WT and Hdac6 KO NK cells on IL-15 stimulation (figure 5J). Collectively, these data demonstrate that HDAC6 enhances NK cell responsiveness to IL-15 and STAT5 signaling by facilitating HSP90 deacetylation.

HDAC6 synergizes with IL-15/STAT5 signaling to boost NK cell antitumor activity

We next postulated that HDAC6 controls NK cell function through the IL-15/STAT5 signaling pathway. First, we treated WT and Hdac6 KO NK cells with STAT5-IN-2, an inhibitor for STAT5 phosphorylation. Flow cytometry analysis revealed that administration of STAT5-IN-2 abrogated the differences in IFN-γ and CD107a levels between WT and Hdac6 KO NK cells on IL-15 stimulation (figure 6A). Moreover, STAT5-IN-2 dampened the augmented TNF-α, IFN-γ and perforin expression in LV-HDAC6 NK-92 cells stimulated with IL-15 (figure 6B). In consistency, 17-AAG treatment also abolished the upregulated levels of effector molecules IFN-γ, TNF-α and CD107a in LV-HDAC6 NK-92 cells (figure 6C), indicating that HSP90-IL-15/STAT5 signaling is involved in the regulation of HDAC6 on effector functions of NK cells. Then, we wondered whether HDAC6 could synergize with IL-15 to improve NK cell antitumor activity. HepG2-luc HCC bearing NCG mice were intraperitoneally injected with IL-15, combined with control or LV-HDAC6 NK-92 cells. In vivo fluorescence imaging showed that the tumor burden in the LV-HDAC6 NK-92+IL-15 group was significantly lower than that in the control group (figure 6D). Moreover, LV-HDAC6 NK+IL-15 group mice had a longer survival period than control mice (figure 6E). Taken together, these results suggest that HDAC6 coordinates IL-15 signaling to boost the functional optimization of NK cells.

Discussion

Since their initial identification several decades ago, NK cells have drawn considerable attention due to their distinctive ability to spontaneously target and destroy virus-infected and tumor cells.²⁴ The intensity of NK cell-mediated immunosurveillance is intrinsically linked to both their absolute number and maturity status. However, the regulatory mechanisms that govern this process have yet to be fully elucidated. Here, our study uncovers HDAC6 as a novel regulator to promote NK cell homeostasis and functional maturation. Hdac6 deficiency leads to the decreased NK cell number and the retarded functional maturation, resulting in the acceleration of tumor progression. Mechanistically, HDAC6 binds with and induces HSP90 deacetylation, which in turn enhances STAT5 signaling and NK cell responsiveness to IL-15 stimulation. Importantly, HDAC6 expression in NK cells correlates with tumor patient prognosis and improves its antitumor efficacy. Our findings confirm that protein acetylation is a pivotal regulator of NK cell homeostasis and maturation, thereby providing a fundamental framework for understanding the regulatory landscape of NK cell biology.

Although HDAC inhibitors were previously reported to suppress NK cell viability and functions, the exact roles of HDAC family members remain unknown. Here we identified significant upregulation of HDAC6 in activated NK cells. Structurally, HDAC6 is defined by the presence of two tandem deacetylase domains, along with a ubiquitin-binding domain and a C-terminal zinc finger motif. Among the HDACs, HDAC6 is unique owing to its cytoplasmic localization and numerous non-histone substrates, including cortactin, HSP90, Ku70, β-catenin, p53, HIF-1α and others.^25–28 HDAC6 involves itself in diverse cellular processes, including DNA damage,²⁹ autophagy and cell migration.³⁰ A growing body of evidence indicates that HDAC6 serves as a key modulator of immune regulation. It was reported that HDAC6 inhibits the function of RoRγt and blocks the pathogenicity of TH17 cells by mediating the cytoplasmic deacetylation of FoxO1.³¹ In addition, HDAC6 involves itself in regulating regulatory T cell (Treg) functions³² and chemotaxis of T cells.³³ In macrophages, HDAC6 deacetylates α-tubulin and cortactin, thereby enhancing the dynamics of microtubule tips and promoting actin assembly during inflammation.³⁴ Here, for the first time to our knowledge, we reported the crucial role of HDAC6 in maintaining NK cell homeostasis and facilitating its functional maturation in a cell-intrinsic manner. Hdac6 deficiency impaired the proliferative potential of NK cells and reduced NK cell numbers. More importantly, Hdac6 KO NK cells were prone to be less mature and functionally defective, which resembles the features of TINKs. Actually, Hdac6 KO NK cells displayed impaired antitumor efficacy for both tumor growth and metastasis. All these results determine the critical roles of HDAC6 in the homeostasis and functional maturation of NK cells. In addition, HDAC inhibitors have been used in the treatment of Duchenne muscular dystrophy,³⁵ as well as in certain malignancies.³⁶ Our study might raise a caution about their potential damage to NK cell antitumor effects and suggests HDAC6 as a promising target that may help optimize NK cell-based immunotherapeutic strategies.

IL-15 and the downstream JAK/STAT5 signaling are critical for NK cell homeostasis and functional maturation.^37
38 We found that Hdac6 deficiency downregulated STAT5 phosphorylation and suppressed IL-15-induced NK cell activation. Indeed, HSP90 was first identified as a direct binding partner for phosphorylated STAT5 (Tyr694), but not to inactive STAT5, in chronic myeloid leukemia.²² Moreover, HSP90 has been proved to be a deacetylation substrate of HDAC6.^26
39 HDAC6 regulated Treg cell function through HSP90 and heat shock factor protein 1.³² Here we disclosed that there was increased deacetylated HSP90 and close interaction between HSP90 and phosphorylated STAT5 in activated NK cells, which was disrupted by HDAC6 knockdown. Moreover, inhibition of HSP90 abolished the effect of HDAC6 on STAT5 phosphorylation and effector functions in NK cells. These data reveal the involvement of the HSP90/STAT5 axis in HDAC6 regulation of NK cell homeostasis and functional maturation. Most importantly, co-administration of IL-15 and HDAC6-overexpressed NK cells exhibited optimized antitumor activity, suggesting a potential combinatorial approach to improve NK cell function.

In summary, our findings provide novel evidence supporting the emerging paradigm in which the balance between protein acetylation and deacetylation regulates the homeostasis and functional state of NK cells. Our findings reveal a previously unrecognized role for HDAC6 in enhancing NK cell immunosurveillance while also highlighting the potential risks associated with the clinical use of HDAC inhibitors.

Materials and methods

Ethics approval and consent to participate

Paired tumor and para-tumor tissues (six pairs) were collected from patients with HCC (four males and two females, age range 20–73 years) at Qilu Hospital of Shandong University and Shandong Provincial Hospital. Inclusion criteria required primary HCC diagnosis and no prior treatment before surgical resection. Diagnostic confirmation relied on cytological evaluation and standard imaging techniques.

Experimental animals

C57BL/6 mice were procured from Beijing Vital River Laboratory Animal Technology. The Hdac6 knockout mouse strain was a generous gift from Professor Jun Zhou at Shandong Normal University. Additionally, CD45.1⁺ mice were kindly supplied by Dr Xiaolong Liu from the Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences. To generate CD45.1⁺CD45.2⁺ mice, CD45.1⁺ mice were crossed with CD45.2⁺ mice. NCG mice were obtained from GemPharmatech. All animals were housed in a specific pathogen-free facility, and all experimental procedures were approved by the Laboratory Animal Center of Shandong University (ECSBMSSDU2019-2-78).

Cell lines

The human NK cell line NK-92 was maintained in MEM-α medium supplemented with 12.5% fetal bovine serum (FBS), 12.5% horse serum, 1% penicillin/streptomycin, 0.2 mmol/L inositol, 0.1 mmol/L β-mercaptoethanol, 0.02 mmol/L folic acid, and 100 U/mL recombinant human IL-2. Additionally, Yac-1 (mouse cell line), K562 (human chronic myelocytic leukemia), and B16-F10 (mouse melanoma) cells were grown in RPMI (Roswell Park Memorial Institute) 1640 medium containing 10% FBS and 1% penicillin/streptomycin. All cell lines, including NK-92, B16-F10, Yac-1, and K562, were acquired from the American Type Culture Collection.

Lentivirus preparation and infection

NK-92 cells were infected with LV-empty or LV-HDAC6 (Shanghai Genechem) at a multiplicity of infection=50 by centrifugal infection for 1 hour and cultured for another 48 hours in supplemented medium. Puromycin was added for selection, and 2 weeks later, NK92 cell lines infected with lentivirus were obtained.

Isolation of mononuclear and NK cells

Liver mononuclear cells were isolated by first perfusing and mincing mouse livers, followed by mechanical dissociation through a 200-gage stainless steel mesh. Erythrocytes were removed using NH4Cl lysis buffer, and the cell suspension was subsequently purified by density gradient centrifugation over 40% Percoll (GE Healthcare). Splenocytes and PB lymphocytes were obtained by pressing the respective tissues through a steel mesh and lysing red blood cells. BM cells were harvested by flushing femurs and tibias, followed by erythrocyte lysis.

NK cells used in cytotoxicity assays, in vitro stimulation experiments, and adoptive transfers were isolated using a MojoSort Mouse NK Cell Isolation Kit (BioLegend). The purity of isolated NK cells exceeded 90% for all experimental procedures.

In vitro stimulation of NK cells

NK-92 cells were treated with PMA (Phorbol 12-myristate 13-acetate) (50 ng/mL) and ionomycin (1 µg/mL) for 1 hour, followed by incubation with brefeldin A (BFA, BioLegend) at 10 µg/mL for an additional 4 hours. Alternatively, isolated NK cells were activated using IL-12 (20 ng/mL) and IL-15 (50 ng/mL) for 16 hours, after which BFA (10 µg/mL) was added for 4 hours of culture.

Flow cytometry analysis

For surface marker detection, cell suspensions were incubated with target-specific antibodies at 4°C for 30 min. For intracellular staining, surface-stained cells were fixed using an intracellular fixation buffer (BioLegend) for 20 min, followed by permeabilization with permeabilization buffer (eBioscience) for 10 min. Antibodies diluted in permeabilization buffer were then used for intracellular labeling. For transcription factor staining, cells were fixed with a Transcription Factor Fixation/Permeabilization kit (eBioscience) for 20 min after surface staining, and subsequently permeabilized for 10 min. CD107a degranulation was evaluated by co-incubating cells with anti-CD107a antibody for 4 hours. Samples were acquired on a CytoFLEX S flow cytometer (Beckman Coulter) and analyzed using FlowJo V.10.6.2 or CytExpert V.2.3.0 software. Details of all antibodies used for flow cytometry staining are provided in online supplemental table 1.

Cytotoxicity assay

In vitro cytotoxicity assays were performed by co-culturing CFSE (Carboxyfluorescein succinimidyl ester)-labeled target cells (YAC-1 or K562) with effector cells (purified NK cells or NK-92 cells) in the presence of IL-2 (100 U/mL) at varying effector-to-target ratios (5:1, 2.5:1, and 1.25:1). The co-cultures were maintained at 37°C under 5% CO_₂ for 4 hours. Cell death was assessed by 7-AAD (7-aminoactinomycin D) staining, with lysed cells identified as CFSE⁺7-AAD⁺ by flow cytometry. For the in vivo cytotoxicity assay, WT and Hdac6 KO mice received an intraperitoneal injection of 2×10⁶ CFSE-labeled Yac-1 cells. After 24 hours, cells were harvested from the peritoneal cavity, and the percentage of CFSE-labeled Yac-1 cells was quantified by flow cytometry.

Mixed BM chimeras

BM cells were harvested from CD45.1⁺ WT and CD45.2⁺ Hdac6 KO mice by flushing the femurs and tibias. Cells from the two genotypes were mixed in a 1:1 ratio, and a total of 1×10⁷ mixed BM cells were intravenously transferred into recipient NCG mice that had received 2.5 Gy lethal irradiation 24 hours earlier. 6 weeks after transplantation, NK cell maturation was analyzed by flow cytometry.

Tumor models establishment and NK cell transfer

For the subcutaneous B16-F10 tumors model, C57BL/6 mice were injected B16-F10 melanoma cells (2×10⁵) into the groin, 1×10⁶ purified WT or Hdac6 KO NK cells were transferred 7 day later via the caudal vein. Tumor growth was monitored by serial caliper measurements, and tumor volume was calculated using the formula ½×a×b², where a and b represent the longest and shortest diameters, respectively.

For B16-F10 melanoma lung metastasis model, mice were established by intravenous injection of 3×10⁵ luciferase-expressing B16-F10 cells, and 7 days later, 1×10⁶ purified splenic NK cells from WT or Hdac6 KO mice were intravenously transferred.

To establish human HCC xenografts, 5×10⁶ HepG2-luciferase cells were injected intraperitoneally into mice, concurrently with the transfer of 2×10⁶ NK92 cells that had been pre-transduced with LV-empty or LV-HDAC6 lentivirus. To sustain NK cell viability in vivo, recombinant human IL-2 (1×10⁵ U; Jiangsu Kingsley Pharmaceuticals) was administered intraperitoneally every 2 days. At 1 or 2 weeks after tumor inoculation, mice were injected intraperitoneally with luciferin and imaged for 1 min using an IVIS Spectrum imaging system (PerkinElmer) to assess tumor burden in vivo.

Based on an expected moderate effect size, a total of animals per group was considered sufficient to maintain statistical efficiency while minimizing animal use, in accordance with the 3Rs (Replacement, Reduction, and Refinement) principles.

Immunoprecipitation assay

NK-92 cells were treated with or without IL-15 (50 ng/mL) for 1 hour, followed by collection and washing in phosphate-buffered saline. After lysis in buffer (Beyotime Biotechnology) supplemented with 1% PMSF (Phenylmethylsulfonyl fluoride) (Beyotime Biotechnology) and 1% phosphatase inhibitor cocktail (Cell Signaling Technology), the lysates were centrifuged at 12,000 rpm for 15 min at 4°C. The resulting supernatants were incubated with specific antiboydies and protein A/G magnetic beads (Beyotime Biotechnology). Following washes, bound proteins were eluted, denatured in SDS-PAGE (Sodium dodecyl sulfate–polyacrylamide gel electrophoresis) loading buffer (Beyotime Biotechnology), and subsequently subjected to western blotting analysis.

Western blotting analysis

Cells were lysed on ice for 30 min using RIPA (Radioimmunoprecipitation assay) buffer (Beyotime). Following centrifugation at 12,000 g for 10 min, the supernatant was collected. Proteins were separated on 10% Bis-Tris gels and transferred to PVDF (Polyvinylidene fluoride) membranes. Membranes were blocked with 5% (w/v) non-fat milk for 2 hours at room temperature, then incubated overnight at 4°C with primary antibodies diluted in 3% (w/v) BSA/TBST (Bovine serum albumin/Tris-buffered saline with Tween-20). After washing, membranes were probed with HRP (Horseradish peroxidase)-conjugated secondary antibodies (Proteintech) for 1 hour at room temperature.

All antibodies used for immunoblotting are listed in online supplemental table 1.

Reverse transcription-quantitative PCR assay

Total RNA was isolated with TRIzol reagent. First-strand complementary DNA (cDNA) synthesis was performed using the Revert Aid First Strand cDNA Synthesis Kit with random primers, following the manufacturer’s protocol. Quantitative real-time PCR was subsequently conducted using SYBR Green Real-Time-qPCR Master Mix. Primer sequences for the target genes are provided in online supplemental table 2.

Statistical analysis

Statistical analysis was performed using GraphPad Prism V.8.0. Differences between two groups were assessed with unpaired two-tailed Student’s t-tests, while comparisons among multiple groups were evaluated by one-way or two-way analysis of variance followed by Tukey’s multiple comparisons test. Data are expressed as mean±SEM. Significance levels are denoted as follows: *p<0.05; **p<0.01; ***p<0.001; ****p<0.0001 and ns indicates not significant.

Supplementary material

online supplemental file 1

jitc-14-7-s001.docx^{(2.5MB, docx)}

DOI: 10.1136/jitc-2026-015167

Acknowledgements

Thanks for the support from Translational Medicine Core Facility of Shandong University for consultation and instrument availability.

The funders had no involvement in the study design; in the collection, analysis, and interpretation of the data; in the writing of the report; and in the decision to submit the paper for publication.

Footnotes

Funding: This work was supported by grants from the National Key Research and Development Program (No. 2022YFA1103402), the National Natural Science Foundation of China (No. 82171805, 82230056, 82402148), Taishan Scholar Project of Shandong Province (No. tstp20231212), Cutting Edge Development Fund of Advanced Medical Research Institute (No. GYY2023QY01), Natural Science Foundation of Shandong Province (No. ZR2023MH212, ZR2023MH094).

Provenance and peer review: Not commissioned; externally peer reviewed.

Patient consent for publication: Not applicable.

Ethics approval: The study protocol was approved by the Ethics Committee of Shandong University School of Basic Medical Sciences (License No. ECSBMSSDU2018-2-031). All procedures complied with the Helsinki Declaration, and written informed consent was obtained from all participating volunteers.

Data availability statement

All data relevant to the study are included in the article or uploaded as supplementary information.

References

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Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

online supplemental file 1

jitc-14-7-s001.docx^{(2.5MB, docx)}

DOI: 10.1136/jitc-2026-015167

Data Availability Statement

All data relevant to the study are included in the article or uploaded as supplementary information.

[R1] 1.Myers JA, Miller JS. Exploring the NK cell platform for cancer immunotherapy. Nat Rev Clin Oncol. 2021;18:85–100. doi: 10.1038/s41571-020-0426-7. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R2] 2.Chiossone L, Dumas P-Y, Vienne M, et al. Natural killer cells and other innate lymphoid cells in cancer. Nat Rev Immunol. 2018;18:671–88. doi: 10.1038/s41577-018-0061-z. [DOI] [PubMed] [Google Scholar]

[R3] 3.Imai K, Matsuyama S, Miyake S, et al. Natural cytotoxic activity of peripheral-blood lymphocytes and cancer incidence: an 11-year follow-up study of a general population. Lancet. 2000;356:1795–9. doi: 10.1016/S0140-6736(00)03231-1. [DOI] [PubMed] [Google Scholar]

[R4] 4.Cózar B, Greppi M, Carpentier S, et al. Tumor-Infiltrating Natural Killer Cells. Cancer Discov. 2021;11:34–44. doi: 10.1158/2159-8290.CD-20-0655. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R5] 5.Laskowski TJ, Biederstädt A, Rezvani K. Natural killer cells in antitumour adoptive cell immunotherapy. Nat Rev Cancer. 2022;22:557–75. doi: 10.1038/s41568-022-00491-0. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R6] 6.Yu J, Freud AG, Caligiuri MA. Location and cellular stages of natural killer cell development. Trends Immunol. 2013;34:573–82. doi: 10.1016/j.it.2013.07.005. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R7] 7.Abel AM, Yang C, Thakar MS, et al. Natural Killer Cells: Development, Maturation, and Clinical Utilization. Front Immunol. 2018;9:1869. doi: 10.3389/fimmu.2018.01869. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R8] 8.Chiossone L, Chaix J, Fuseri N, et al. Maturation of mouse NK cells is a 4-stage developmental program. Blood. 2009;113:5488–96. doi: 10.1182/blood-2008-10-187179. [DOI] [PubMed] [Google Scholar]

[R9] 9.Crinier A, Narni-Mancinelli E, Ugolini S, et al. SnapShot: Natural Killer Cells. Cell. 2020;180:1280–1280.e1. doi: 10.1016/j.cell.2020.02.029. [DOI] [PubMed] [Google Scholar]

[R10] 10.Huntington ND, Tabarias H, Fairfax K, et al. NK cell maturation and peripheral homeostasis is associated with KLRG1 up-regulation. J Immunol . 2007;178:4764–70. doi: 10.4049/jimmunol.178.8.4764. [DOI] [PubMed] [Google Scholar]

[R11] 11.Wang X, Zhao X-Y. Transcription Factors Associated With IL-15 Cytokine Signaling During NK Cell Development. Front Immunol. 2021;12:610789. doi: 10.3389/fimmu.2021.610789. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R12] 12.Wong P, Foltz JA, Chang L, et al. T-BET and EOMES sustain mature human NK cell identity and antitumor function. J Clin Invest. 2023;133:e162530. doi: 10.1172/JCI162530. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R13] 13.Tan S, Guo X, Li M, et al. Transcription factor Zhx2 restricts NK cell maturation and suppresses their antitumor immunity. J Exp Med. 2021;218:e20210009. doi: 10.1084/jem.20210009. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R14] 14.Ceccacci E, Minucci S. Inhibition of histone deacetylases in cancer therapy: lessons from leukaemia. Br J Cancer. 2016;114:605–11. doi: 10.1038/bjc.2016.36. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R15] 15.Pace M, Williams J, Kurioka A, et al. Histone Deacetylase Inhibitors Enhance CD4 T Cell Susceptibility to NK Cell Killing but Reduce NK Cell Function. PLoS Pathog . 2016;12:e1005782. doi: 10.1371/journal.ppat.1005782. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R16] 16.Ni L, Wang L, Yao C, et al. The histone deacetylase inhibitor valproic acid inhibits NKG2D expression in natural killer cells through suppression of STAT3 and HDAC3. Sci Rep. 2017;7:45266. doi: 10.1038/srep45266. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R17] 17.Rossi LE, Avila DE, Spallanzani RG, et al. Histone deacetylase inhibitors impair NK cell viability and effector functions through inhibition of activation and receptor expression. J Leukoc Biol. 2012;91:321–31. doi: 10.1189/jlb.0711339. [DOI] [PubMed] [Google Scholar]

[R18] 18.Zhang X, Wang P, Chen T, et al. Kctd9 Deficiency Impairs Natural Killer Cell Development and Effector Function. Front Immunol. 2019;10:744. doi: 10.3389/fimmu.2019.00744. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R19] 19.Desbois M, Rusakiewicz S, Locher C, et al. Natural killer cells in non-hematopoietic malignancies. Front Immunol. 2012;3:395. doi: 10.3389/fimmu.2012.00395. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R20] 20.Gotthardt D, Trifinopoulos J, Sexl V, et al. JAK/STAT Cytokine Signaling at the Crossroad of NK Cell Development and Maturation. Front Immunol. 2019;10:2590. doi: 10.3389/fimmu.2019.02590. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R21] 21.Moulick K, Ahn JH, Zong H, et al. Affinity-based proteomics reveal cancer-specific networks coordinated by Hsp90. Nat Chem Biol. 2011;7:818–26. doi: 10.1038/nchembio.670. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R22] 22.Kovacs JJ, Murphy PJM, Gaillard S, et al. HDAC6 regulates Hsp90 acetylation and chaperone-dependent activation of glucocorticoid receptor. Mol Cell. 2005;18:601–7. doi: 10.1016/j.molcel.2005.04.021. [DOI] [PubMed] [Google Scholar]

[R23] 23.Ai J, Wang Y, Dar JA, et al. HDAC6 regulates androgen receptor hypersensitivity and nuclear localization via modulating Hsp90 acetylation in castration-resistant prostate cancer. Mol Endocrinol . 2009;23:1963–72. doi: 10.1210/me.2009-0188. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R24] 24.Cerottini J-C, Brunner KT. Cell-mediated cytotoxicity, allograft rejection, and tumor immunity. Adv Immunol. 1974;18:67–132. doi: 10.1016/s0065-2776(08)60308-9. [DOI] [PubMed] [Google Scholar]

[R25] 25.Li P, Ge J, Li H. Lysine acetyltransferases and lysine deacetylases as targets for cardiovascular disease. Nat Rev Cardiol. 2020;17:96–115. doi: 10.1038/s41569-019-0235-9. [DOI] [PubMed] [Google Scholar]

[R26] 26.Li T, Zhang C, Hassan S, et al. Histone deacetylase 6 in cancer. J Hematol Oncol. 2018;11:111. doi: 10.1186/s13045-018-0654-9. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R27] 27.Yang X-J, Seto E. The Rpd3/Hda1 family of lysine deacetylases: from bacteria and yeast to mice and men. Nat Rev Mol Cell Biol. 2008;9:206–18. doi: 10.1038/nrm2346. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R28] 28.Lee Y-S, Lim K-H, Guo X, et al. The cytoplasmic deacetylase HDAC6 is required for efficient oncogenic tumorigenesis. Cancer Res. 2008;68:7561–9. doi: 10.1158/0008-5472.CAN-08-0188. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R29] 29.Jin J, Meng T, Yu Y, et al. Human HDAC6 senses valine abundancy to regulate DNA damage. Nature. 2025;637:215–23. doi: 10.1038/s41586-024-08248-5. [DOI] [PubMed] [Google Scholar]

[R30] 30.Moreno-Gonzalo O, Mayor F, Sánchez-Madrid F. HDAC6 at Crossroads of Infection and Innate Immunity. Trends Immunol. 2018;39:591–5. doi: 10.1016/j.it.2018.05.004. [DOI] [PubMed] [Google Scholar]

[R31] 31.Qiu W, Wang B, Gao Y, et al. Targeting Histone Deacetylase 6 Reprograms Interleukin-17-Producing Helper T Cell Pathogenicity and Facilitates Immunotherapies for Hepatocellular Carcinoma. Hepatology. 2020;71:1967–87. doi: 10.1002/hep.30960. [DOI] [PubMed] [Google Scholar]

[R32] 32.de Zoeten EF, Wang L, Butler K, et al. Histone deacetylase 6 and heat shock protein 90 control the functions of Foxp3(+) T-regulatory cells. Mol Cell Biol. 2011;31:2066–78. doi: 10.1128/MCB.05155-11. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R33] 33.Tsuji G, Okiyama N, Villarroel VA, et al. Histone deacetylase 6 inhibition impairs effector CD8 T-cell functions during skin inflammation. J Allergy Clin Immunol. 2015;135:1228–39. doi: 10.1016/j.jaci.2014.10.002. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R34] 34.Yan B, Xie S, Liu Y, et al. Histone deacetylase 6 modulates macrophage infiltration during inflammation. Theranostics. 2018;8:2927–38. doi: 10.7150/thno.25317. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R35] 35.Mozzetta C, Sartorelli V, Steinkuhler C, et al. HDAC inhibitors as pharmacological treatment for Duchenne muscular dystrophy: a discovery journey from bench to patients. Trends Mol Med. 2024;30:278–94. doi: 10.1016/j.molmed.2024.01.007. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R36] 36.Biersack B, Polat S, Höpfner M. Anticancer properties of chimeric HDAC and kinase inhibitors. Semin Cancer Biol. 2022;83:472–86. doi: 10.1016/j.semcancer.2020.11.005. [DOI] [PubMed] [Google Scholar]

[R37] 37.Anton OM, Peterson ME, Hollander MJ, et al. Trans-endocytosis of intact IL-15Rα-IL-15 complex from presenting cells into NK cells favors signaling for proliferation. Proc Natl Acad Sci U S A. 2020;117:522–31. doi: 10.1073/pnas.1911678117. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R38] 38.Ma S, Caligiuri MA, Yu J. Harnessing IL-15 signaling to potentiate NK cell-mediated cancer immunotherapy. Trends Immunol. 2022;43:833–47. doi: 10.1016/j.it.2022.08.004. [DOI] [PMC free article] [PubMed] [Google Scholar]

[R39] 39.Zhu Y, Feng M, Wang B, et al. New insights into the non-enzymatic function of HDAC6. Biomed Pharmacother. 2023;161:114438. doi: 10.1016/j.biopha.2023.114438. [DOI] [PubMed] [Google Scholar]

PERMALINK

HDAC6 orchestrates NK cell maturation and antitumor immunity

Wenwen Yang

Panpan Tian

Xiaowei Guo

Miaomiao Ding

Rong Xiao

Zhuanchang Wu

Xuetian Yue

Chunyang Li

Lifen Gao

Jun Zhou

Chun-hong Ma

Xueen Li

Jianping Wang

Xiaohong Liang

Abstract

Background

Methods

Results

Conclusion

WHAT IS ALREADY KNOWN ON THIS TOPIC

WHAT THIS STUDY ADDS

HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY

Introduction

Results

Reduced HDAC6 expression in TINK cells correlates with poor patient survival

Loss of Hdac6 leads to reduced NK cell number and impaired proliferation

Hdac6 deficiency impairs NK cell maturation

Loss of Hdac6 weakens the effector functions and antitumor activity of NK cells

HDAC6 promotes HSP90 deacetylation and chaperone activity for phosphorylated STAT5 in NK cells

HDAC6 synergizes with IL-15/STAT5 signaling to boost NK cell antitumor activity

Discussion

Materials and methods

Ethics approval and consent to participate

Experimental animals

Cell lines

Lentivirus preparation and infection

Isolation of mononuclear and NK cells

In vitro stimulation of NK cells

Flow cytometry analysis

Cytotoxicity assay

Mixed BM chimeras

Tumor models establishment and NK cell transfer

Immunoprecipitation assay

Western blotting analysis

Reverse transcription-quantitative PCR assay

Statistical analysis

Supplementary material

Acknowledgements

Footnotes

Data availability statement

References

Associated Data

Supplementary Materials

Data Availability Statement

ACTIONS

PERMALINK

RESOURCES

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