Rocaglamide promotes infiltration and differentiation of T cells and coordinates with PD-1 inhibitor to overcome checkpoint resistance in multiple tumor models.

Tumor-infiltrating lymphocyte (TIL) deficiency is the most conspicuous obstacle to limit the cancer immunotherapy. Immune checkpoint inhibitors (ICIs), such as anti-PD-1 antibody, have achieved great success in clinical practice. However, due to the limitation of response rates of ICIs, some patients fail to benefit from monotherapy. Thus, novel combination therapy that could improve the response rates emerges as new strategies for cancer treatment. Here, we reported that the natural product rocaglamide (RocA) increased tumor-infiltrating T cells and promoted Th17 differentiation of CD4+ TILs. Despite RocA monotherapy upregulated PD-1 expression of TILs, which was considered as the consequence of T cell activation, combining RocA with anti-PD-1 antibody significantly downregulated the expression of PD-1 and promoted proliferation of TILs. Taken together, these findings demonstrated that RocA could fuel the T cell anti-tumor immunity and revealed the remarkable potential of RocA as a therapeutic candidate when combining with the ICIs.

Glutathione­degrading enzymes in the complex landscape of tumors (Review).

Glutathione (GSH)­degrading enzymes are essential for starting the first stages of GSH degradation. These enzymes include extracellular γ­glutamyl transpeptidase (GGT) and intracellular GSH­specific γ­glutamylcyclotransferase 1 (ChaC1) and 2. These enzymes are essential for cellular activities, such as immune response, differentiation, proliferation, homeostasis regulation and programmed cell death. Tumor tissue frequently exhibits abnormal expression of GSH­degrading enzymes, which has a key impact on the development and spread of malignancies. The present review summarizes gene and protein structure, catalytic activity and regulation of GSH­degrading enzymes, their vital roles in tumor development (including regulation of oxidative and endoplasmic reticulum stress, control of programmed cell death, promotion of inflammation and tumorigenesis and modulation of drug resistance in tumor cells) and potential role as diagnostic biomarkers and therapeutic targets.

Traditional Chinese Medicine for Cancer Treatment.

In recent years, due to advancements in medical conditions and the development of scientific research, the fundamental research of TCM antitumor treatments has progressed from the cellular level to the molecular and genetic levels. Previous studies have demonstrated the significant role of traditional Chinese medicine (TCM) in antitumor therapy through various mechanisms and pathways. Its mechanism of action is closely associated with cancer biology across different stages. This includes inhibiting tumor cell proliferation, blocking invasion and metastasis to surrounding tissues, inducing tumor cell apoptosis, inhibiting tumor angiogenesis, regulating immune function, maintaining genome stability, preventing mutation, and regulating cell energy metabolism. The use of TCM for eliciting antitumor effects not only has a good therapeutic effect and low side effects, it also provides a solid theoretical basis for clinical treatment and medication. This paper reviews the mechanism of the antitumor effects of TCM based on tumor characteristics. Through our review, we found that TCM not only directly inhibits tumors, but also enhances the body's immunity, thereby indirectly inducing an antitumor effect. This function aligns with the TCM theory of "strengthening the body's resistance to eliminate pathogenic factors". Furthermore, TCM will play a significant role in tumor treatment in clinical settings.

Rocaglamide regulates iron homeostasis by suppressing hepcidin expression.

The anemia of inflammation (AI) is characterized by the presence of inflammation and abnormal elevation of hepcidin. Accumulating evidence has proved that Rocaglamide (RocA) was involved in inflammation regulation. Nevertheless, the role of RocA in AI, especially in iron metabolism, has not been investigated, and its underlying mechanism remains elusive. Here, we demonstrated that RocA dramatically suppressed the elevation of hepcidin and ferritin in LPS-treated mice cell line RAW264.7 and peritoneal macrophages. In vivo study showed that RocA can restrain the depletion of serum iron (SI) and transferrin (Tf) saturation caused by LPS. Further investigation showed that RocA suppressed the upregulation of hepcidin mRNA and downregulation of Fpn1 protein expression in the spleen and liver of LPS-treated mice. Mechanistically, this effect was attributed to RocA's ability to inhibit the IL-6/STAT3 pathway, resulting in the suppression of hepcidin mRNA and subsequent increase in Fpn1 and TfR1 expression in LPS-treated macrophages. Moreover, RocA inhibited the elevation of the cellular labile iron pool (LIP) and reactive oxygen species (ROS) induced by LPS in RAW264.7 cells. These findings reveal a pivotal mechanism underlying the roles of RocA in modulating iron homeostasis and also provide a candidate natural product on alleviating AI.

Euphohelioscopin A enhances NK cell antitumor immunity through GSDME-triggered pyroptosis.

Immune evasion by cancer cells poses a significant challenge for natural killer (NK) cell-based immunotherapy. Pyroptosis, a newly discovered form of programmed cell death, has shown great potential for enhancing the antitumor immunity of NK cells. Consequently, targeting pyroptosis has become an attractive strategy for boosting NK cell activity against cancer. In this study, various assays were conducted, including NK cell cytotoxicity assays, flow cytometry, xenograft tumor models, real-time PCR, and ELISA to assess NK cell-mediated cell killing, as well as gene and protein expressions. The results indicated that Euphohelioscopin A (Eupho-A), a potential pyroptosis activator, enhances NK cell-mediated lysis of tumor cells, resulting in inhibiting tumor growth that could be reversed by NK cell depletion. Furthermore, we found that Eupho-A significantly enhanced IFN-γ production in NK cells and synergistically up-regulated GSDME with IFN-γ in cancer cells. Eupho-A also increased the cleavage of GSDME, promoting GZMB-induced pyroptosis, which could be reversed by GSDME knockdown and IFN-γ blockade. Overall, the findings suggested that Eupho-A enhanced NK cell-mediated killing of cancer cells by triggering pyroptosis, making Eupho-A a promising pyroptosis activator with great potential for using in NK cell-based cancer immunotherapy.

Ailanthone inhibits non-small cell lung cancer growth and metastasis through targeting UPF1/GAS5/ULK1 signaling pathway.

BACKGROUND: Targeting long non-coding RNAs (LncRNAs) is a novel and promising approach in cancer therapy. In our previous study, we investigated the effects of ailanthone (aila), the main active compound derived from the stem barks of Ailanthus altissima (Mill.) Swingle, on the growth of non-small cell lung cancer (NSCLC) cells. Although we observed significant inhibition of NSCLC cell growth of aila, the underlying mechanisms involving LncRNAs, specifically LncRNA growth arrest specific 5 (GAS5), remain largely unknown. METHODS: To further explore the impact of aila on NSCLC, we performed a series of experiments. Firstly, we confirmed the inhibitory effect of aila on NSCLC cell growth using multiple assays, including MTT, wound healing, transwell assay, as well as subcutaneous and metastasis tumor mice models in vivo. Next, we utilized cDNA microarray and RT-QPCR to identify GAS5 as the primary target of aila. To verify the importance of GAS5 in aila-induced tumor inhibition, we manipulated GAS5 expression levels by constructing GAS5 over-expression and knockdown NSCLC cell lines. Furthermore, we investigated the upstream and downstream signaling pathways of GAS5 through western blot and RT-QPCR analysis. RESULTS: Our results showed that aila effectively increased GAS5 expression, as determined by microarray analysis. We also observed that aila significantly enhanced GAS5 expression in a dose- and time-dependent manner across various NSCLC cell lines. Notably, over-expression of GAS5 led to a significant suppression of NSCLC cell tumor growth; while aila had minimal inhibitory effect on GAS5-knockdown NSCLC cells. Additionally, we discovered that aila inhibited ULK1 and autophagy, and this inhibition was reversed by GAS5 knockdown. Moreover, we found that aila up-regulated GAS5 expression by suppressing UPF1-mediated nonsense-mediated mRNA decay (NMD). CONCLUSION: In summary, our findings suggest that aila promotes GAS5 expression by inhibiting UPF1-mediated NMD, leading to the repression of ULK1-mediated autophagy and subsequent inhibitory effects on NSCLC cells. These results indicate that aila is a potent enhancer of GAS5 and holds promising potential for application in NSCLC therapy. However, our research is currently focused only on NSCLC. It remains to be determined whether aila can also inhibit the growth of other types of tumors through the UPF1/GAS5/ULK1 signaling pathway. In future studies, we can further investigate the mechanisms by which aila suppresses other types of tumors and potentially broaden the scope of its application in cancer therapy.

[Research progress on immunotherapy based on NK cells for hepatocellular carcinoma].

Hepatocellular carcinoma (HCC) is well characterized as a heterogeneous disease. Its late-stage diagnosis and chemotherapy resistance make it one of the refractory tumors in China. Natural killer (NK) cells play a significant role in immune surveillance. However, NK cells become dysfunctional in the progression of HCC, leading to tumor immune escape. This article reviews the recent progress on different strategies of NK cell-based immunotherapy in treating HCC, including direct adoptive NK cell transfer, gene engineering in NK cell, NK cell receptor targeting, immunosuppressive microenvironment modification, and tumor toxicity enhancement by cytokines or traditional Chinese medicine. These NK cell-based strategies have shown promising therapeutic potential.

Carpets with visual cues can improve gait in Parkinson's disease patients: may be independent of executive function.

BACKGROUND: Gait impairment is common in Parkinson's disease (PD) patients, which greatly reduces their quality of life. Executive dysfunction is associated with gait impairment. Compensatory strategies, including visual cues, have been shown to be effective in improving PD gait. In this study, we aimed to understand whether carpets with visual cues could improve PD gait, and how the improvement varies across patients with different executive function state. METHODS: We designed carpets with chessboard and stripe cues. A total of 65 Chinese PD patients were recruited. Movement Disorder Society Unified Parkinson's Disease Rating Scale, L-dopa equivalent daily dosage, Hoehn & Yahr stage, Frontal Assessment Battery, Mini Mental State Examination Scale, Hamilton Anxiety Scale, and Hamilton Depression Scale were evaluated. Gait parameters including stride length, gait speed and fall risk were recorded by a wearable electronic device. RESULTS: The stride length and gait speed were significantly improved and the fall risk was significantly mitigated when PD patients walked on carpets with chessboard and stripe patterns. Further analysis showed the amelioration of gait parameters was independent of executive dysfunction. CONCLUSIONS: Our study demonstrates that carpets with visual cues can improve the gait of PD patients even in those with mild executive dysfunction.

Isolated unilateral oculomotor palsy caused by pure midbrain infarction: a case report.

Purpose: Multiple etiologies may cause oculomotor nerve palsies. Identification of different etiologies is very important for subsequent treatment. Midbrain infarction is a rare cause of oculomotor nerve palsy. Materials and methods: We herein present a case of isolated unilateral oculomotor paresis caused by pure midbrain infarction. Results: Her pupillary sphincter and inferior rectus muscles were selectively spared. The symptoms were completely relieved after two months of antiplatelet therapy. We proposed that fibers from Edinger-Westphal nucleus and inferior rectus nucleus do not course through the paramedian area of the midbrain. Conclusions: Our report adds to the understanding of fascicles arrangement in the midbrain.

The traditional chinese medicine monomer Ailanthone improves the therapeutic efficacy of anti-PD-L1 in melanoma cells by targeting c-Jun.

BACKGROUND: C-Jun, a critical component of AP-1, exerts essential functions in various tumors, including melanoma, and is believed to be a druggable target for cancer therapy. Unfortunately, no effective c-Jun inhibitors are currently approved for clinical use. The advent of immune checkpoint inhibitor (ICI) has brought a paradigm shift in melanoma therapy, but more than half of patients fail to exhibit clinical responses. The exploration of new combination therapies has become the current pursuit of melanoma treatment strategy. This study aims to screen out Chinese herbal monomers that can target c-Jun, explore the combined effect of c-Jun inhibitor and ICI, and further clarify the related molecular mechanism.  METHODS: We adopted a combinatorial screening strategy, including molecular docking, ligand-based online approaches and consensus quantitative structure-activity relationship (QSAR) model, to filter out c-Jun inhibitors from a traditional Chinese medicine (TCM) library. A mouse melanoma model was used to evaluate the therapeutic efficacy of monotherapy and combination therapy. Multicolor flow cytometry was employed to assess the tumor microenvironment (TME). Multiple in vitro assays were performed to verify down-streaming signaling pathway. CD4 + T-cell differentiation assay was applied to investigate Treg differentiation in vitro. RESULTS: Ailanthone (AIL) was screened out as a c-Jun inhibitor, and inhibited melanoma cell growth by directly targeting c-Jun and promoting its degradation. Surprisingly, AIL also facilitated the therapeutic efficacy of anti-programmed death ligand-1 (PD-L1) in melanoma cells by reducing the infiltration of Tregs in TME. Additionally, AIL treatment inhibited c-Jun-induced PD-L1 expression and secretion. As a consequence, Treg differentiation was attenuated after treatment with AIL through the c-Jun/PD-L1 axis. CONCLUSION: Our findings identified AIL as a novel c-Jun inhibitor, and revealed its previously unrecognized anti-melanoma effects and the vital role in regulating TME by Treg suppression, which provides a novel combination therapeutic strategy of c-Jun inhibition by AIL with ICI. AIL down-regulates c-Jun by reducing its stability, and inhibits the function of Tregs via AIL-c-Jun-PD-L1 pathway, ultimately suppressing melanoma progression and enhancing the efficacy of anti-PD-L1.

Neck pain and absence of cranial nerve symptom are clues of cervical myelopathy mimicking stroke: Two case reports.

BACKGROUND: Cervical myelopathy is a potential stroke imitator, for which intravenous thrombolysis would be catastrophic. CASE SUMMARY: We herein present two cases of cervical myelopathy. The first patient presented with acute onset of right hemiparesis and urinary incontinence, and the second patient presented with sudden-onset right leg monoplegia. The initial diagnoses for both of them were ischemic stroke. However, both of them lacked cranial nerve symptom and suffered neck pain at the beginning of onset. Their cervical spinal cord lesions were finally confirmed by cervical computed tomography. A literature review showed that neck pain and absence of cranial nerve symptom are clues of cervical myelopathy. CONCLUSION: The current report and the review remind us to pay more attention to these two clues in suspected stroke patients, especially those within the thrombolytic time window.

Case report: Blepharospasm in peak-dose dyskinesia may benefit from amantadine in Parkinson's disease.

Introduction: Blepharospasm is uncommon in Parkinson's disease, especially in the peak-dose dyskinesia period. Case presentation: We herein present the case of a patient with PD who developed blepharospasm in the peak-dose dyskinesia period. The symptom was improved by taking amantadine. Conclusion: The current report expands the phenomenology of peak-dose dykinesia in PD to include dystonic blepharospasm. This complication of levodopa therapy may respond to amantadine despite the dystonic appearance of movements.

Parkinsonism-Hyperpyrexia Syndrome and Dyskinesia-Hyperpyrexia Syndrome in Parkinson's Disease: Two Cases and Literature Review.

Parkinsonism-hyperpyrexia syndrome (PHS) and dyskinesia-hyperpyrexia syndrome (DHS) are rare but exhibit life-threatening complications in Parkinson's disease (PD). We herein presented two cases of PD patients and performed a comprehensive and comparative literature review for these two syndromes. The first case was diagnosed as PHS with cerebral salt wasting syndrome caused by abrupt withdrawal of antiparkinsonian medication. Her symptoms were gradually remitted with reinstitution of the medication. The second one was an early-stage PD patient diagnosed as DHS in association with abuse of antiparkinsonian drugs. Her symptoms were gradually remitted with reduced dosage of dopaminergic drugs. Results of literature reviews revealed a total of 56 and 13 cases of PHS and DHS, respectively, and they were more likely to occur in elderly and long-term PD patients. These two syndromes showed different female-to-male ratio, similar mortality, and different recovery time. There were stark differences between PHS and DHS, including triggers (abrupt drug stoppage versus drug abuse), symptoms (worsened tremor and rigidity versus continuous dyskinesia), and treatment (drug reinstitution versus drug reduction). In summary, our reports and the review provide new insights into PHS and DHS in association with PD and may facilitate rapid discrimination of the syndromes for timely and proper treatment to reduce mortality.

Rocaglamide promotes the infiltration and antitumor immunity of NK cells by activating cGAS-STING signaling in non-small cell lung cancer.

Background: Natural killer (NK) cell-based immunotherapy is clinically limited due to insufficient tumor infiltration in solid tumors. We have previously found that the natural product rocaglamide (RocA) can enhance NK cell-mediated killing of non-small cell lung cancer (NSCLC) cells by inhibiting autophagy, and autophagic inhibition has been shown to increase NK cell tumor infiltration in melanoma. Therefore, we hypothesized that RocA could increase NK cell infiltration in NSCLC by autophagy inhibition. Methods: Flow cytometry, RNA-sequencing, real-time PCR, Western blotting analysis, and xenograft tumor model were utilized to assess the infiltration of NK cells and the underlying mechanism. Results: RocA significantly increased the infiltration of NK cells and the expressions of CCL5 and CXCL10 in NSCLC cells, which could not be reversed by the inhibitions of autophagy/ULK1, JNK and NF-κB. However, such up-regulation could be suppressed by the inhibitions of TKB1 and STING. Furthermore, RocA dramatically activated the cGAS (cyclic GMP-AMP synthase)-STING (stimulator of interferon genes) signaling pathway, and the inhibition/depletion of STING ablated the up-regulation of CCL5 and CXCL10, NK cell infiltration, and tumor regression induced by RocA. Besides, RocA damaged mitochondrial DNA (mtDNA) and promoted the cytoplasmic release of mtDNA. The mPTP inhibitor cyclosporin A could reverse RocA-induced cytoplasmic release of mtDNA. Conclusions: RocA could promote NK cell infiltration by activating cGAS-STING signaling via targeting mtDNA, but not by inhibiting autophagy. Taken together, our current findings suggested that RocA was a potent cGAS-STING agonist and had a promising potential in cancer immunotherapy, especially in NK cell-based immunotherapy.

Diterpenoids from Euphorbia helioscopia and their enhancement of NK cell-mediated killing of NSCLC cells.

Fourteen previously undescribed diterpenoids, including an unusual diterpenoid (1) with a 9,10-seco-jatrophane skeleton, ten jatrophane-type diterpenoids (2-11), two lathyrane-type diterpenoids (12, 13), and an abietane-type diterpenoid (14), together with thirty-six known ones (15-50), were isolated from the whole plants of Euphorbia helioscopia L. The structures of the new isolates were characterized by spectroscopic methods, single-crystal X-ray diffraction analysis, and computational prediction of ECD and chemical shifts. Thirty-nine abundant diterpenoids were evaluated for their enhancement of NK cell-mediated killing of NSCLC cells. As a result, compounds 24, 33, and 41 were found to significantly enhance the killing activity of NK cells towards H1299-luci cells and A549-luci cells at the concentration of 2.5 µM.

Cystathionine ß-synthase mediated PRRX2/IL-6/STAT3 inactivation suppresses Tregs infiltration and induces apoptosis to inhibit HCC carcinogenesis.

BACKGROUND: Hepatocellular carcinoma (HCC) is characterized by inflammation and immunopathogenesis. Accumulating evidence has shown that the cystathionine ß-synthase/hydrogen sulfide (CBS/H2S) axis is involved in the regulation of inflammation. However, roles of CBS in HCC development and immune evasion have not been systematically investigated, and their underlying mechanisms remain elusive. Here, we investigated the roles of CBS in tumor cells and tumor microenvironment of HCC. METHODS: 236 HCC samples were collected to detect the expression of CBS, cleaved Caspase-3 and paired related homeobox 2 (PRRX2) and the number of immune cells. HCC cell lines were employed to examine the effects of CBS on cellular viability, apoptosis and signaling in vitro. Cbs heterozygous knockout mice, C57BL/6 mice, nude mice and non-obese diabetic severe combined immunodeficiency mice were used to investigate the in vivo functions of CBS. RESULTS: Downregulation of CBS was observed in HCC, and low expression of CBS predicted poor prognosis in HCC patients. CBS overexpression dramatically promoted cellular apoptosis in vitro and inhibited tumor growth in vivo. Activation of the Cbs/H2S axis also reduced the abundance of tumor-infiltrating Tregs, while Cbs deficiency promoted Tregs-mediated immune evasion and boosted tumor growth in Cbs heterozygous knockout mice. Mechanistically, CBS facilitated the expression cleaved Caspase-3 in tumor cells, and on the other hand, suppressed Foxp3 expression in Tregs via inactivating IL-6/STAT3 pathway. As a transcription factor of IL-6, PRRX2 was reduced by CBS. Additionally, miR-24-3p was proven to be an upstream suppressor of CBS in HCC. CONCLUSIONS: Our results indicate the antitumor function of CBS in HCC by inactivation of the PRRX2/IL-6/STAT3 pathway, which may serve as a potential target for HCC clinical immunotherapy.

Ze-Qi-Tang Formula Induces Granulocytic Myeloid-Derived Suppressor Cell Apoptosis via STAT3/S100A9/Bcl-2/Caspase-3 Signaling to Prolong the Survival of Mice with Orthotopic Lung Cancer.

Non-small-cell lung cancer (NSCLC) remains the most common malignancy with the highest morbidity and mortality worldwide. In our previous study, we found that a classic traditional Chinese medicine (TCM) formula Ze-Qi-Tang (ZQT), which has been used in the treatment of respiratory diseases for thousands of years, could directly inhibit the growth of human NSCLC cells via the p53 signaling pathway. In this study, we explored the immunomodulatory functions of ZQT. We found that ZQT significantly prolonged the survival of orthotopic lung cancer model mice by modulating the tumor microenvironment (TME). ZQT remarkably reduced the number of MDSCs (especially G-MDSCs) and inhibited their immunosuppressive activity by inducing apoptosis in these cells via the STAT3/S100A9/Bcl-2/caspase-3 signaling pathway. When G-MDSCs were depleted, the survival promotion effect of ZQT and its inhibitory effect on lung luminescence signal disappeared in tumor-bearing mice. This is the first study to illustrate the immunomodulatory effect of ZQT in NSCLC and the underlying molecular mechanism.

Tanshinone IIA enhances susceptibility of non-small cell lung cancer cells to NK cell-mediated lysis by up-regulating ULBP1 and DR5.

Natural killer (NK) cells have a great potential in cancer immunotherapy. However, their therapeutic efficacy is clinically limited owing to cancer cell immune escape. Therefore, it is urgently necessary to develop novel method to improve the antitumor immunity of NK cells. In the present study, it was found that the natural product tanshinone IIA (TIIA) enhanced NK cell-mediated killing of non-small cell lung cancer (NSCLC) cells. TIIA in combination with adoptive transfer of NK cells synergistically suppressed the tumor growth of NSCLC cells in an immune-incompetent mouse model. Furthermore, TIIA significantly inhibited the tumor growth of Lewis lung cancer (LLC) in an immune-competent syngeneic mouse model, and such inhibitory effect was reversed by the depletion of NK cells. Moreover, TIIA increased expressions of ULBP1 and DR5 in NSCLC cells, and inhibition of DR5 and ULBP1 reduced the enhancement of NK cell-mediated lysis by TIIA. Besides, TIIA increased the levels of p-PERK, ATF4 and CHOP. Knockdown of ATF4 completely reversed the up-regulation of ULBP1 and DR5 by TIIA in all detected NSCLC cells, while knockdown of CHOP only partly reduced these enhanced expressions in small parts of NSCLC cells. These results demonstrated that TIIA could increase the susceptibility of NSCLC cells to NK cell-mediated lysis by up-regulating ULBP1 and DR5, suggesting that TIIA had a promising potential in cancer immunotherapy, especially in NK cell-based cancer immunotherapy.

Targeting CD155 by rediocide-A overcomes tumour immuno-resistance to natural killer cells.

CONTEXT: Therapeutic benefits of immunotherapy are restricted by cancer immune-resistance mechanisms. Rediocide-A (Red-A), a natural product extracted from Traditional Chinese Medicine, is a promising agent to battle against cancer which acts as an immune checkpoint inhibitor. OBJECTIVE: To investigate the effect of Red-A on NK-cell tumouricidal activity. MATERIALS AND METHODS: NK cells were co-cultured with A549 or H1299 cells and treated with 10 or 100 nM Red-A for 24 h. Cells treated with 0.1% dimethyl sulphoxide (DMSO) was employed as vehicle control. NK cell-mediated cytotoxicity was detected by biophotonic cytotoxicity and impedance assay. Degranulation, granzyme B, NK cell-tumour cell conjugates and ligands profiling were detected by flow cytometry. Interferon-γ (IFN- γ) production was assessed by enzyme-linked immunosorbent assay (ELISA). RESULTS: Red-A increased NK cell-mediated lysis of A549 cells by 3.58-fold (21.86% vs. 78.27%) and H1299 cells by 1.26-fold (59.18% vs. 74.78%), compared to vehicle control. Granzyme B level was increased by 48.01% (A549 cells) and 53.26% (H1299 cells) after 100 nM Red-A treatment. INF-γ level was increased by 3.23-fold (A549 cells) and 6.77-fold (H1299 cells) after 100 nM Red-A treatment. Red-A treatment down-regulated the expression level of CD155 by 14.41% and 11.66% in A549 cells and H1299 cells, respectively, leading to the blockade of tumour immuno-resistance to NK cells. CONCLUSIONS: Red-A overcomes immuno-resistance of NSCLCs to NK cells by down-regulating CD155 expression, which shows the possibility of developing checkpoint inhibitors targeting TIGIT/CD155 signalling to overcome immuno-resistance of cancer cells.

Grain-sized moxibustion promotes NK cell antitumour immunity by inhibiting adrenergic signalling in non-small cell lung cancer.

Lung cancer is the leading cause of cancer-related death worldwide, and non-small cell lung cancer (NSCLC) accounts for 85% of lung cancer diagnoses. As an ancient therapy, moxibustion has been used to treat cancer-related symptoms in clinical practice. However, its antitumour effect on NSCLC remains largely unexplored. In the present study, a Lewis lung cancer (LLC) xenograft tumour model was established, and grain-sized moxibustion (gMoxi) was performed at the acupoint of Zusanli (ST36). Flow cytometry and RNA sequencing (RNA-Seq) were used to access the immune cell phenotype, cytotoxicity and gene expression. PK136, propranolol and epinephrine were used for natural killer (NK) cell depletion, ß-adrenoceptor blockade and activation, respectively. Results showed that gMoxi significantly inhibited LLC tumour growth. Moreover, gMoxi significantly increased the proportion, infiltration and activation of NK cells, whereas it did not affect CD4+ and CD8+ T cells. NK cell depletion reversed gMoxi-mediated tumour regression. LLC tumour RNA-Seq indicated that these effects might be related to the inhibition of adrenergic signalling. Surely, ß-blocker propranolol clearly inhibited LLC tumour growth and promoted NK cells, and gMoxi no longer increased tumour regression and promoted NK cells after propranolol treatment. Epinephrine could inhibit NK cell activity, and gMoxi significantly inhibited tumour growth and promoted NK cells after epinephrine treatment. These results demonstrated that gMoxi could promote NK cell antitumour immunity by inhibiting adrenergic signalling, suggesting that gMoxi could be used as a promising therapeutic regimen for the treatment of NSCLC, and it had a great potential in NK cell-based cancer immunotherapy.