Natural cytotoxic activity of peripheral-blood lymphocytes and cancer incidence: an 11-year follow-up study of a general population

N6-methyladenosine RNA base modification regulates NKG2D-dependent and cytotoxic genes expression in natural killer cells

BACKGROUND

Breast cancer (BC) is the most commonly diagnosed cancer in women. N6-methyladenosine (m6A) is the most prevalent internal modification in mammalian mRNAs and plays a crucial role in various biological processes. However, its function in Natural killer (NK) cells in BC remains unclear. NK cells are essential for cancer immunosurveillance. This study aims to assess m6A levels in transcripts involved in the NKG2D cytotoxicity signaling pathway in NK cells of BC patients compared to controls and find out its impact on mRNA levels. Additionally, it evaluates how deliberately altering m6A levels in NK cells affects mRNA and protein expression of NKG2D pathway genes and NK cell functionality.

METHODS

m6A methylation in transcripts of NKG2D-pathway-related genes in BC patients and controls was determined using methylated RNA immunoprecipitation-reverse transcription-PCR (MERIP-RT-PCR). To deliberately alter m6A levels in primary cultured human NK cells, the m6A demethylases, FTO and ALKBH5, were knocked out using the CRISPR-CAS9 system, and FTO was inhibited using Meclofenamic acid (MA). The impact of m6A alteration on corresponding mRNA and protein levels was assessed using RT-qPCR and Western blot analysis or flow cytometry, respectively. Additionally, NK cell functionality was evaluated through degranulation and 51Cr release cytotoxicity assays.

RESULTS

Transcripts of NKG2D, an activating receptor that detects stressed non-self tumour cells, had significantly higher m6A levels in the 3' untranslated region (3'UTR) accompanied by a marked reduction in their corresponding mRNA levels in BC patients compared to controls. Conversely, transcripts of ERK2 and PRF1 exhibited significantly lower m6A levels escorted with higher mRNA expression in BC patients relative to controls. The mRNA levels of PI3K, PAK1 and GZMH were also significantly elevated in BC patients. Furthermore, artificially increasing transcripts' m6A levels via MA in cultured primary NK cells reduced mRNA levels of NKG2D pathway genes and death receptor ligands but did not affect protein expression or NK cell functionality.

CONCLUSION

Transcripts with higher m6A levels in the 3'UTR region were less abundant, and vice versa. However, changes in mRNA levels of the target genes didn't impact their corresponding protein levels or NK cell functionality.

The roles of natural killer cells in bone and arthritic disease: a narrative review

The skeletal system is responsible for the body's support and motor functions, and can be pathologically affected by factors, such as metabolism, autoimmune inflammation, tumors, and infections. Regarding tissue localization and biological function, the immune system is deeply involved in the physiological and pathological processes of the skeletal system. As a regulator and effector cell of the innate immune system, natural killer (NK) cells can exert cytotoxic effects through cell contact and immunomodulatory effects through cytokine secretion. In the past 30 years, many advances have been made regarding the role of NK cells and their derived cytokines on bone and joints. In this review, the role of NK cells in the physiological activities of bone remodeling is summarized first, focusing on osteoclast differentiation and function. Subsequently, the roles of NK cells in osteoarthritis, bone tumors, and bone diseases caused by microbial infections are described, meanwhile, some conflicting research results are discussed. By reviewing the state-of-the-art progress of NK cells in the above-mentioned bone physiological and pathological processes, it is helpful to clarify the blind spots of current research and provide some references for the integrated evaluation of immune factors in the study of skeletal system diseases.

Diagnostic, prognostic, and immunological roles of FUT8 in lung adenocarcinoma and lung squamous cell carcinoma

Lung cancer remains the leading cause of malignant tumors worldwide in terms of the incidence and mortality, posing a significant threat to human health. Given that distant metastases typically occur at the time of initial diagnosis, leading to a poor 5-year survival rate among patients, it is crucial to identify markers for diagnosis, prognosis, and therapeutic efficacy monitoring. Abnormal glycosylation is a hallmark of cancer cells, characterized by the disruption of core fucosylation, which is predominantly driven by the enzyme fucosyltransferase 8 (FUT8). Evidence indicates that FUT8 is a pivotal enzyme in cancer onset and progression, influencing cellular glycosylation pathways. Utilizing bioinformatics approaches, we have investigated FUT8 in lung cancer, resulting in a more systematic and comprehensive understanding of its role in the disease's pathogenesis. In this study, we employed bioinformatics to analyze the differential expression of FUT8 between LUAD and LUSC. We observed upregulation of FUT8 in both LUAD and LUSC, associated with unfavorable prognosis, and higher diagnostic utility in LUAD. GO/KEGG analysis revealed a primary association between LUAD and the spliceosome. Immunologically, FUT8 expression was significantly associated with immune cell infiltration and immune checkpoint activity, with a notable positive correlation with M2 macrophage infiltration. Our analysis of FUT8 indicates that it may serve as a potential biomarker for lung cancer diagnosis and prognosis, and could represent a therapeutic target for LUAD and LUSC immunotherapy.

Unravelling NK cell subset dynamics and specific gene signatures post-ibrutinib therapy in chronic lymphocytic leukaemia via single-cell transcriptomics

BACKGROUND

As part of the innate immune system, NK cells contribute to optimizing cancer immunotherapy strategies and are becoming a focal point in cancer research. However, limited research has been conducted to further investigate changes in NK cell subsets and their critical genes following ibrutinib treatment in CLL patients.

METHODS

Peripheral blood samples from patients clinically and pathologically diagnosed with monoclonal B-cell lymphocytosis (MBL), newly diagnosed with CLL (ND-CLL), postibrutinib-treated patients who achieved a complete response (CR) or partial response (PR), and those with Richter's syndrome (RS) were collected. Single-cell transcriptome sequencing was performed, followed by pseudotemporal analysis and functional enrichment to characterize the NK cell subsets. Mendelian randomization analysis and colocalization analysis were employed to identify key genes. Multiple algorithms were used for immune infiltration analysis, and drug sensitivity analysis was conducted to pinpoint potential therapeutic agents.

RESULTS

Three distinct NK cell subsets were identified: CD56bright_NK cells, CD56dim_NK cells, and a highly cytotoxic CLL_NK subset. The core genes of the CLL_NK subset were elucidated through Mendelian randomization and colocalization analyses. A cell subset-specific novel index (CNI) was constructed based on these core genes and was shown to be capable of predicting responses to immunotherapy. Oncopredictive algorithms and molecular docking screenings further identified semaxanib and ulixertinib as potential therapeutic candidates for CLL.

CONCLUSION

The CLL_NK subset plays a crucial role in the development and progression of CLL. The CNI, derived from its key genes, holds promise as a predictor of immune therapeutic responses, highlighting the significance of CLL_NK subset dynamics and their genetic underpinnings in CLL management.

Natural killer cells: the immune frontline against circulating tumor cells

Natural killer (NK) play a key role in controlling tumor dissemination by mediating cytotoxicity towards cancer cells without the need of education. These cells are pivotal in eliminating circulating tumor cells (CTCs) from the bloodstream, thus limiting cancer spread and metastasis. However, aggressive CTCs can evade NK cell surveillance, facilitating tumor growth at distant sites. In this review, we first discuss the biology of NK cells, focusing on their functions within the tumor microenvironment (TME), the lymphatic system, and circulation. We then examine the immune evasion mechanisms employed by cancer cells to inhibit NK cell activity, including the upregulation of inhibitory receptors. Finally, we explore the clinical implications of monitoring circulating biomarkers, such as NK cells and CTCs, for therapeutic decision-making and emphasize the need to enhance NK cell-based therapies by overcoming immune escape mechanisms.

WGCNA-ML-MR integration: uncovering immune-related genes in prostate cancer

Background

Prostate cancer is one of the most common tumors in men, with its incidence and mortality rates continuing to rise year by year. Prostate-specific antigen (PSA) is the most commonly used screening indicator, but its lack of specificity leads to overdiagnosis and overtreatment. Therefore, identifying new biomarkers related to prostate cancer is crucial for the early diagnosis and treatment of prostate cancer.

Methods

This study utilized datasets from the Gene Expression Omnibus (GEO) to screen for differentially expressed genes (DEGs) and employed Weighted Gene Co-expression Network Analysis (WGCNA) to identify driver genes highly associated with prostate cancer within the modules. The intersection of differentially expressed genes and driver genes was taken, and Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analyses were performed. Furthermore, a machine learning algorithm was used to screen for core genes and construct a diagnostic model, which was then validated in an external validation dataset. The correlation between core genes and immune cell infiltration was analyzed, and Mendelian randomization (MR) analysis was conducted to identify biomarkers closely related to prostate cancer.

Results

This study identified six core biomarkers: SLC14A1, ARHGEF38, NEFH, MSMB, KRT23, and KRT15. MR analysis demonstrated that MSMB may be an important protective factor for prostate cancer. In q-PCR experiments conducted on tumor tissues and adjacent non-cancerous tissues from prostate cancer patients, it was found that: compared to the adjacent non-cancerous tissues, the expression level of ARHGEF38 in prostate cancer tumor tissues significantly increased, while the expression levels of SLC14A1, NEFH, MSMB, KRT23, and KRT15 significantly decreased. To further validate these findings at the protein level, we conducted Western blot analysis, which corroborated the q-PCR results, demonstrating consistent expression patterns for all six biomarkers. IHC results confirmed that ARHGEF38 protein was highly expressed in tumor tissues, while MSMB expression was markedly reduced.

Conclusion

Our study reveals that SLC14A1, ARHGEF38, NEFH, MSMB, KRT23, and KRT15 are potential diagnostic biomarkers for prostate cancer, among which MSMB may play a protective role in prostate cancer.

Anti-breast cancer effect of Phellinus pini and its chemical composition characterization

Phellinus pini (P. pini) has been widely utilized as a traditional medicinal macrofungus in China and various East Asian countries. Modern pharmacological studies have shown that P. pini has important application value in anti-tumor therapy. However, its main anti-breast cancer active substances and mechanism are still unclear. In this study, we demonstrated that the methanol extract of Phellinus pini (PPE) could significantly inhibit the viability of 4 T1 cells, induce apoptosis, decrease mitochondrial membrane potential and S phase arrest of 4 T1 cells. PPE can restore the imbalance of intestinal flora caused by breast cancer and regulate the content of endogenous metabolites such as amino acids. Q Exactive UPLC-MS/MS analysis showed that polyphenols are the main chemical components that exert the efficacy. These results provide experimental support for the potential future treatment of breast cancer with P. pini.

Genome-wide CRISPR/Cas9 screen reveals factors that influence the susceptibility of tumor cells to NK cell-mediated killing

BACKGROUND

Natural killer (NK) cells exhibit potent cytotoxic activity against various cancer cell types. Over the past five decades, numerous methodologies have been employed to elucidate the intricate molecular mechanisms underlying NK cell-mediated tumor control. While significant progress has been made in elucidating the interactions between NK cells and tumor cells, the regulatory factors governing NK cell-mediated tumor cell destruction are not yet fully understood. This includes the diverse array of tumor ligands recognized by NK cells and the mechanisms that NK cells employ to eliminate tumor cells.

METHODS

In this study, we employed a genome-wide CRISPR/Cas9 screening approach in conjunction with functional cytotoxicity assays to delineate the pathways modulating the susceptibility of colon adenocarcinoma HCT-116 cells to NK cell-mediated cytotoxicity.

RESULTS

Analysis of guide RNA distribution in HCT-116 cells that survived co-incubation with NK cells identified ICAM-1 as a pivotal player in the NKp44-mediated immune synapse, with NKp44 serving as an activating receptor crucial for the elimination of HCT-116 tumor cells by NK cells. Furthermore, disruption of genes involved in the apoptosis or interferon (IFN)-γ signaling pathways conferred resistance to NK cell attack. We further dissected that NK cell-derived IFN-γ promotes mitochondrial apoptosis in vitro and exerts control over B16-F10 lung metastases in vivo.

CONCLUSION

Monitoring ICAM-1 levels on the surface of tumor cells or modulating its expression should be considered in the context of NK cell-based therapy. Furthermore, promoting FasL expression on the NK cell surface is reaffirmed as an important strategy to enhance NK cell-mediated tumor killing, offering an additional avenue for therapeutic optimization. Additionally, considering the diffusion properties of IFN-γ, our findings highlight the potential of leveraging NK cell-derived IFN-γ to enhance direct tumor cell killing and facilitate bystander effects via cytokine diffusion, warranting further investigation.

The Regulation of Cellular Senescence in Cancer

Cellular senescence is a stable state of cell cycle arrest caused by telomere shortening or various stresses. After senescence, cells cease dividing and exhibit many age-related characteristics. Unlike the halted proliferation of senescence cells, cancer cells are considered to have unlimited growth potential. When cells display senescence-related features, such as telomere loss or stem cell failure, they can inhibit tumor development. Therefore, inducing cells to enter a senescence state can serve as a barrier to tumor cell development. However, many recent studies have found that sustained senescence of tumor cells or normal cells under certain circumstances can exert environment-dependent effects of tumor promotion and inhibition by producing various cytokines. In this review, we first introduce the causes and characteristics of induced cellular senescence, analyze the senescence process of immune cells and cancer cells, and then discuss the dual regulatory role of cell senescence on tumor growth and senescence-induced therapies targeting cancer cells. Finally, we discuss the role of senescence in tumor progression and treatment opportunities, and propose further studies on cellular senescence and cancer therapy.

Is the vIL-10 Protein from Cytomegalovirus Associated with the Potential Development of Acute Lymphoblastic Leukemia?

Leukemia is a hematologic malignancy; acute lymphoblastic leukemia (ALL) is the most prevalent subtype among children rather than in adults. Orthoherpesviridae family members produce proteins during latent infection phases that may contribute to cancer development. One such protein, viral interleukin-10 (vIL-10), closely resembles human interleukin-10 (IL-10) in structure. Research has explored the involvement of human cytomegalovirus (hCMV) in the pathogenesis of ALL. However, the limited characterization of its latent-phase proteins restricts a full understanding of the relationship between hCMV infection and leukemia progression. Studies have shown that hCMV induces an inflammatory response during infection, marked by the release of cytokines and chemokines. Inflammation may, therefore, play a role in how hCMV contributes to oncogenesis in pediatric ALL, possibly mediated by latent viral proteins. The classification of a virus as oncogenic is based on its alignment with cancer's established hallmarks. Viruses can manipulate host cellular mechanisms, causing dysregulated cell proliferation, evasion of apoptosis, and genomic instability. These processes lead to mutations, chromosomal abnormalities, and chronic inflammation, all of which are vital for carcinogenesis. This study aims to investigate the role of vIL-10 during the latent phase of hCMV as a potential factor in leukemia development.

CAR-NK cell therapy: a potential antiviral platform

Viral infections persist as a significant cause of morbidity and mortality worldwide. Conventional therapeutic approaches often fall short in fully eliminating viral infections, primarily due to the emergence of drug resistance. Natural killer (NK) cells, one of the important members of the innate immune system, possess potent immunosurveillance and cytotoxic functions, thereby playing a crucial role in the host's defense against viral infections. Chimeric antigen receptor (CAR)-NK cell therapy has been developed to redirect the cytotoxic function of NK cells specifically towards virus-infected cells, further enhancing their cytotoxic efficacy. In this manuscript, we review the role of NK cells in antiviral infections and explore the mechanisms by which viruses evade immune detection. Subsequently, we focus on the optimization strategies for CAR-NK cell therapy to address existing limitations. Furthermore, we discuss significant advancements in CAR-NK cell therapy targeting viral infections, including those caused by severe acute respiratory syndrome coronavirus 2, human immunodeficiency virus, hepatitis B virus, human cytomegalovirus, and Epstein-Barr virus.

Distinct profiles of osteoclast and dendritic cell-mediated expansion and functional activation of NK and T cells

Osteoclasts (OCs) and dendritic cells (DCs) induce expansion and functional activation of NK and T cells. When comparing OCs with DC-induced activation in NK cells, OCs induced significantly higher cell expansion and functional activation of NK cells as compared to DCs, either from healthy individuals or those obtained from cancer patients. However, no differences could be seen in the levels of cell expansion and functional activation in T cells activated by OCs or DCs, either from healthy individuals or those from cancer patients. OCs selectively expanded and activated CD8 + T cells, whereas DCs expanded and activated CD4 + T cells. In addition, both allogeneic and autologous OCs induced similar levels of cell expansion and functional activation of NK and T cells. Together, these findings highlighted the essential roles of OCs in expanding and activating the cytotoxic effectors of NK, and CD8 + T cells, and demonstrated several differences when compared to the effect of DCs.

Identification of CKAP2 as a Potential Target for Prevention of Gastric Cancer Progression: A Multi-Omics Study

Gastric cancer (GC) ranks as one of the most prevalent malignant tumors globally. The subtle manifestation of its early-stage symptoms often results in many GC patients being diagnosed at a late or advanced stage, thereby posing significant obstacles to the effectiveness of chemotherapy treatments. Therefore, identifying early biomarkers for GC is crucial. In recent years, an increasing number of studies have highlighted the pivotal role that aging plays in the progression of cancer. Among the various proteins involved, Cytoskeleton-associated protein 2 (CKAP2) emerges as a crucial player in controlling cell proliferation, regulating mitosis and cell division, and exerting a significant influence on the aging process. We employed a bioinformatics approach to assess the causal association between aging-related genes and GC and explore the potential significance of CKAP2 in GC by analyzing data sourced from various repositories, including Genotype Tissue Expression (GTEx), GWAS Catalog, The Database of Cell Senescence Genes (CellAge), The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), Human Protein Atlas (HPA), and the Comparative Toxicology Genome Database (CTD). Our research summarized the causal relationship between CKAP2 expression and the development risk of GC, differential expression in GC, the relationship with the prognosis of GC, genetic correlation, functional analysis, and immune cell infiltration, and explored the interaction of CKAP2 and chemical substances. The findings revealed that an elevation in CKAP2 expression correlated with a reduced likelihood of developing GC. There was a significant difference in the expression of CKAP2 between GC and normal patients. Specifically, there was higher expression in GC compared to normal patients. In addition, CKAP2 has been proven to have diagnostic value in GC, and elevated levels of CKAP2 expression are indicative of a more favorable prognosis. Immune infiltration analysis revealed the relationship between CKAP2 and tumor immune microenvironment, while the Comparative Toxicology Genome Database (CTD) identified a small molecule compound that may target CKAP2. In summary, through comprehensive multivariate analyses, we identified and validated the potential role that CKAP2 may play in GC. Therefore, CKAP2 shows potential as an indicator for both the diagnosis and prognosis of GC, making it worthy of further clinical investigation.

Enhanced Immune Functions of In Vitro Human Natural Killer Cells and Splenocytes in Immunosuppressed Mice Supplemented with Mature Silkworm Products

OBJECTIVES

The immune-enhancing properties of steamed mature silkworm, known as HongJam (HJ), were investigated using human interleukin-2-independent Natural Killer 92 (NK92-MI) cells and a cyclophosphamide intraperitoneal injection-induced immunosuppressed mice model (CPA-IP). White Jade variety mature silkworm HJ (WJ-HJ) was used to prepare WJ-HJ supercritical fluid extracts (WJ-SCE) and WJ-HJ-supplemented feeds.

RESULTS

Treatment with WJ-SCE significantly enhanced proliferation, migration, and cytotoxicity of NK92-MI cells against various cancer cells while improving mitochondrial function and ATP production (p < 0.05). In CPA-IP mice, consumption of WJ-HJ-supplemented feeds restored immune function by improving body weight, immune organ indices, immunoglobulin levels, and blood cytokines. Splenocyte proliferation and cytotoxicity were significantly elevated in both saline intraperitoneal injection (Sal-IP) and CPA-IP groups with WJ-HJ supplementation, independent of mitogen activation (p < 0.05).

CONCLUSIONS

These results suggest that WJ-HJ enhances immune modulation and immune surveillance functions of NK cells by improving mitochondrial and cytotoxic functions. WJ-HJ holds promise as a functional food for immune enhancement, pending clinical validation.

Natural Killer Cell-Secreted IFN-γ and TNF-α Mediated Differentiation in Lung Stem-like Tumors, Leading to the Susceptibility of the Tumors to Chemotherapeutic Drugs

We demonstrate that natural killer (NK) cells induce a higher cytotoxicity against lung cancer stem-like cells (hA549) compared to differentiated lung cancer cell lines (H292). The supernatants from split-anergized NK cells (IL-2 and anti-CD16 mAb-treated NK cells) induced differentiation in hA549. Differentiated lung cancer cell line (H292) and NK cells differentiated hA549 expressed reduced NK cell-mediated cytotoxicity but expressed higher sensitivity to chemotherapeutic drugs. This finding validated our previous reports demonstrating that the levels of tumor killing by NK cells and by chemotherapeutic drugs correlate directly and indirectly, respectively, with the stage and levels of tumor differentiation. We also demonstrate the role of IFN-γ and TNF-α in inducing tumor differentiation. NK cells' supernatants or IFN-γ and TNF-α-induced tumor differentiation was blocked when we used antibodies against IFN-γ and TNF-α. Therefore, IFN-γ and TNF-α released from NK cells play a significant role in differentiating tumors, resulting in increased susceptibility of tumors to chemotherapeutic drugs. We also observed the different effects of MHC-class I antibodies in CSCs vs. differentiated tumors. Treatment with anti-MHC-class I decreased NK cell-mediated cytotoxicity in hA549 tumors, whereas it increased NK cell-mediated cytotoxicity when differentiated tumors were treated with antibodies against MHC-class I.

Urolithin A increases the natural killer activity of PBMCs in patients with prostate cancer

Background

The natural killer (NK) activity of peripheral blood mononuclear cells (PBMCs) is a crucial defense against the onset and spread of cancer. Studies have shown that patients with reduced NK activity are more susceptible to cancer, and NK activity tends to decrease due to cancer-induced immune suppression. Enhancing the natural cytotoxicity of PBMCs remains a significant task in cancer research.

Methods

This study investigates the potential of urolithin A, a polyphenolic metabolite produced by the gut microbiota, to enhance the natural cytotoxicity of PBMCs in prostate cancer patients and healthy subjects. We investigated the possible role of aryl hydrocarbon receptor (AhR) in this capability of urolithin A. We analyzed the ability of PBMCs preincubated with urolithin A, AhR agonist or antagonist to kill K562 (human chronic myelogenous leukemia) target cells.

Results

Our results demonstrate that urolithin A enhances the natural cytotoxicity of PBMCs in a dose-dependent manner. Specifically, at a concentration of 10 μM, urolithin A increased the NK activity of PBMCs from prostate cancer patients by an average of 23% (95% CI, 7%-38%). In addition, urolithin A modulates the level of cytokine production by PBMCs, decreasing the level of fractalkine, IL-8, and MCP-3. An AhR antagonist (CH223191, 1 μM) also increased NK activity, while an AhR agonist (β-naphthoflavone, 10 μM) did not increase NK activity and partially inhibited the urolithin A-induced enhancement.

Conclusion

Urolithin A increases the NK activity of PBMCs from patients with prostate cancer and healthy subjects, and the AhR may be involved in this capability of urolithin A.

The emergence of DNAM-1 as the facilitator of NK cell-mediated killing in ovarian cancer

Introduction

Ovarian cancer (OC) is the sixth most common malignancy in women and the poor 5-year survival emphasises the need for novel therapies. NK cells play an important role in the control of malignant disease but the nature of tumour-infiltrating and peripheral NK cells in OC remains unclear.

Methods

Using flow cytometric analysis, we studied the phenotype and function of NK cells in blood, primary tumour and metastatic tissue in 80 women with OC. The cell type contexture of metastatic OC tissue was explored utilising scRNAseq analysis, with a focus on portraying an immunogenic tumour microenvironment and determining the characteristics of a dysfunctional NK cell population.

Results

The proportion of peripheral NK cells was markedly elevated with a highly activated profile and increased cytotoxicity. In contrast, NK cell numbers in primary tumour and metastasis were substantially reduced, with downregulation of activatory receptors together with elevated PD-1 expression. scRNA-Seq identified 5 NK cell subpopulations along with increased exhausted and immature NK cells within tumour tissue compared to normal tissue. These features were attenuated following chemotherapy where higher levels of activated and cytotoxic NK cells associated with improved disease-free survival. Correlation of NK cell phenotype with clinical outcomes revealed high levels of DNAM-1 expression on tissue-localised and peripheral NK cells to be associated with reduced survival. Expression of PVR, the DNAM-1 ligand, was significantly increased on tumours and DNAM-1 mediated NK cell lysis of primary tumour tissue was observed in vitro.

Discussion

These findings reveal profound modulation of the tumour tissue and systemic profile of NK cells which likely contributes to the high rates of local progression and metastasis seen with OC. Immunotherapeutic approaches that overcome local immune suppression and enhance DNAM-1-targeted lysis of OC offer the potential to improve disease control.

Circular RNA circPHLPP2 promotes tumor growth and anti-PD-1 resistance through binding ILF3 to regulate IL36γ transcription in colorectal cancer

BACKGROUND

Most Colorectal Cancer (CRC) patients exhibit limited responsiveness to anti-programmed cell death protein 1 (PD-1) therapy, with the underlying mechanisms remaining elusive. Circular RNAs (circRNAs) play a significant role in tumorigenesis and development, with potential applications in tumor screening and predicting treatment efficacy. However, there are few studies exploring the role of circRNAs in CRC immune evasion.

METHODS

circRNA microarrays were used to identify circPHLPP2. RT-qPCR was used to examine the associations between the expression level of circPHLPP2 and the clinical characteristics of CRC patients. MTS assay, clone formation experiment, subcutaneous tumor implantation and multicolor flow cytometry were used to confirm the biological function of circPHLPP2. RAN-seq, RT-qPCR, and WB experiments were performed to investigate the downstream signaling pathways involved in circPHLPP2. RNA pull-down, RNA immunoprecipitation (RIP) and immunofluorescence staining were performed to identify the proteins associated with circPHLPP2.

RESULTS

circPHLPP2 is up-regulated in CRC patients who exhibit resistance to anti-PD-1 based therapy. circPHLPP2 significantly promotes the proliferation and tumor growth of CRC cells. Knockdown of circPhlpp2 enhances the efficacy of anti-PD-1 in vivo. Mechanistically, the specific interaction between circPHLPP2 and ILF3 facilitates the nuclear accumulation of ILF3, which subsequently enhances the transcription of IL36γ. This process reduces NK cell infiltration and impairs NK cells' granzyme B and IFN-γ production, thereby promoting tumor progression.

CONCLUSIONS

Overall, our findings reveal a novel mechanism by which circRNA regulates CRC immune evasion. circPHLPP2 may serve as a prognostic biomarker and potential therapeutic target for CRC patients.

Cross-talk between immune cells and tumor cells in non-Hodgkin lymphomas arising in common variable immunodeficiency

INTRODUCTION

CVID is the commonest and most symptomatic primary immune deficiency of adulthood. NHLs are the most prevalent malignancies in CVID. The cross-talk between tumor cells and immune cells may be an important risk factor in lymphomagenesis.

AREAS COVERED

The present review highlights immune cell, genetic and histopathological alterations in the CVID-associated NHLs.

EXPERT OPINION

CVID patients exhibit some notable immune defects that may predispose to lymphomas. T/NK cell defects including reduced T cells, naïve CD4+T cells, T regs, and Th17 cells, increased CD8+T cells with reduced T cell proliferative and cytokine responses and reduced iNKT and NK cell count and cytotoxicity. B cell defects include increased transitional and CD21low B cells, clonal IgH gene rearrangements, and increased BCMA levels. Increase in IL-9, sCD30 levels, and upregulation of BAFF-BAFFR signaling are associated with lymphomas in CVID. Increased expression of PFTK1, duplication of ORC4L, germline defects in TACI, NFKB1, and PIK3CD, and somatic mutations in NOTCH2 and MYD88 are reported in CVID-associated lymphomas. Upregulation of PD-L1-PD-1 pathway may also promote lymphomagenesis in CVID. These abnormalities need to be explored as prognostic or predictive markers of CVID-associated NHLs by large multicentric studies.

A Comparison of Cellular Immune Response and Immunological Biomarkers in Laparoscopic Surgery for Colorectal Cancer and Benign Disorders

BACKGROUND

Surgical trauma causes immune impairment, but it is largely unknown whether surgery for cancer and benign diseases instigate comparable levels of immune inhibition. Here, we compared the impact of laparoscopic surgery on immunological biomarkers in patients with colorectal cancer (CRC) and ventral hernia (VH).

METHODS

Natural Killer cell activity (NKA), leukocyte subsets, and soluble programmed death ligand 1 (sPD-L1) were measured in blood samples collected from CRC (n = 29) and VH (n = 9) patients preoperatively (PREOP) and on postoperative day (POD) 1, 3-6, 2 weeks and 3 months. NKA was evaluated by the NK Vue assay that uses the level of IFNγ as a surrogate marker of NKA. Normal NKA was defined as IFNγ > 250 pg/mL and low NKA was defined as IFNγ < 250 pg/mL.

RESULTS

The CRC cohort was classified into either PREOPLOW having preoperative low NKA or PREOPHIGH having preoperative normal NKA. The median NKA of the PREOPLOW subset was only in the normal range in the POD3 months sample, whereas median NKA of the PREOPHIGH subset and the VH cohort were only low in the POD1 sample. While PREOPLOW differed from VH in the PREOP-, POD1-, and POD3-6 samples (P =.0006, P = .0181, and P = .0021), NKA in PREOPHIGH and VH differed in the POD1 samples (P = .0226). There were no apparent differences in the distribution of leukocyte subsets in the perioperative period between the cohorts.

CONCLUSION

CRC patients with preoperative normal NKA and VH patients showed the same pattern of recovery in NKA, while the CRC subset with preoperative low NKA seemed to experience prolonged NK cell impairment. As low NKA is associated with recurrence, preoperative level of NKA may identify patients who will benefit from immune-enhancing therapy in the perioperative period.

Coley's Toxin to First Approved Therapeutic Vaccine-A Brief Historical Account in the Progression of Immunobiology-Based Cancer Treatment

Cancer immunobiology is one of the hot topics of discussion amongst researchers today, and immunotherapeutic modalities are among the selected few emerging approaches to cancer treatment that have exhibited a promising outlook. However, immunotherapy is not a new kid on the block; it has been around for centuries. The origin of cancer immunotherapy in modern medicine can be traced back to the initial reports of spontaneous regression of malignant tumors in some patients following an acute febrile infection, at the turn of the twentieth century. This review briefly revisits the historical accounts of immunotherapy, highlighting some of the significant developments in the field of cancer immunobiology, that have been instrumental in bringing back the immunotherapeutic approaches to the forefront of cancer research. Some of the topics covered are: Coley's toxin-the first immunotherapeutic; the genesis of the theory of immune surveillance; the discovery of T lymphocytes and dendritic cells and their roles; the role of tumor antigens; relevance of tumor microenvironment; the anti-tumor (therapeutic) ability of Bacillus Calmette- Guérin; Melacine-the first therapeutic vaccine engineered; theories of immunoediting and immunophenotyping of cancer; and Provenge-the first FDA-approved therapeutic vaccine. In this review, head and neck cancer has been taken as the reference tumor for narrating the progression of cancer immunobiology, particularly for highlighting the advent of immunotherapeutic agents.

Advances in Induced Pluripotent Stem Cell-Derived Natural Killer Cell Therapy

Natural killer (NK) cells are cytotoxic lymphocytes of the innate immune system capable of killing virus-infected cells and/or cancer cells. The commonly used NK cells for therapeutic applications include primary NK cells and immortalized NK cell lines. However, primary NK cell therapy faces limitations due to its restricted proliferation capacity and challenges in stable storage. Meanwhile, the immortalized NK-92 cell line requires irradiation prior to infusion, which reduces its cytotoxic activity, providing a ready-made alternative and overcoming these bottlenecks. Recent improvements in differentiation protocols for iPSC-derived NK cells have facilitated the clinical production of iPSC-NK cells. Moreover, iPSC-NK cells can be genetically modified to enhance tumor targeting and improve the expansion and persistence of iPSC-NK cells, thereby achieving more robust antitumor efficacy. This paper focuses on the differentiation-protocols efforts of iPSC-derived NK cells and the latest progress in iPSC-NK cell therapy. Additionally, we discuss the current challenges faced by iPSC-NK cells and provide an outlook on future applications and developments.

Risks of malignancies related to disease-modifying antirheumatic drugs in rheumatoid arthritis: a pharmacovigilance analysis using the FAERS database

Objectives

Over the years when disease-modifying antirheumatic drugs (DMARDs) have been used in rheumatoid arthritis patients, reports of malignancies have emerged. This study aims to investigate the association between malignancies and DMARDs by using data extracted from the Food and Drug Administration Adverse Event Reporting System (FAERS).

Methods

FAERS data (January 2019 to December 2023) were reviewed. For each drug-event pair, the disproportionality analysis was conducted to evaluate the risk of malignancy. Multivariate logistic regression was implemented to mitigate potential biases. Moreover, the time to onset of malignancy was also evaluated.

Results

We conducted a detailed search for rheumatoid arthritis indications and identified a total of 17,412 adverse event reports associated with malignancies, with selective DMARDs designated as the role code "primary suspect". At the preferred term level, there were 198 positive signals, among which the lower limit of the 95% confidence interval for the information component is 3.55 for squamous cell carcinoma of the skin, 2.39 for breast cancer, and 2.27 for lymphoproliferative disorder. In comparison to other DMARDs, targeted synthetic DMARDs were associated with a broader range of malignancies at both preferred term and Standardized MedDRA Queries levels. The number of adverse events reported in female patients is approximately 2-3 times higher than men, and the median age across the population was approximately 62 years. In terms of onset time, the conventional synthetic DMRADs exhibited a relatively longer median time, ranging from 3.58 to 7.08 years, while the targeted synthetic DMARDs demonstrated a shorter median time of 0.83-1.67 years.

Conclusion

Our study uncovers varying degrees of malignancy risks related to DMARDs, with a significantly higher risk observed in targeted synthetic DMARDs. Additionally, novel malignancy signals, not documented in product labels, have been detected. In the future, further research will be necessary to validate our findings.

Germline natural killer cell receptors modulating the T cell response

In addition to their central role during innate responses, NK cells regulate adaptive immunity through various mechanisms. A wide array of innate receptors has been involved in the NK cell regulatory function. However, the clinical implications of these regulatory pathways are poorly understood. Here, we review the experimental evidence on the effects of NK cells on T cells and their positive and negative consequences for disease outcome during T cell responses in humans.

Development and validation of machine learning models for young-onset colorectal cancer risk stratification

Incidence of young-onset colorectal cancer (YOCRC, younger than 50) has significantly increased worldwide. The performance of fecal immunochemical test in detecting YOCRC is unsatisfactory. Using routine clinical data, we aimed to develop machine learning (ML) models to identify individuals with high-risk YOCRC who require further colonoscopy. We retrospectively extracted data of 10,874 young individuals. Multiple supervised ML techniques were devised to distinguish individuals with and without CRC, classifiers were trained, internally validated and temporally validated. In internal validation cohort, Random Forest (RF) ML model demonstrated good performance with AUC of 0.859 and highest recall of 0.840. In temporal validation cohort, the RF ML model also exhibited good classification performance, achieving AUC of 0.888 and highest recall of 0.872. RF algorithm-based approach is effective and feasible in YOCRC risk stratification. This could be valuable in assessing the risk of YOCRC so that clinical management, including further colonoscopy, can be subsequently made. (Registration: This study was registered with ClinicalTrials.gov (NCT06342622) on March 15, 2024.).

Use of a platform with lens-free shadow imaging technology to monitor natural killer cell activity

Natural killer (NK) cells are a crucial component of the innate immune system. This study introduces Cellytics NK, a novel platform for rapid and precise measurement of NK cell activity. This platform combines an NK-specific activation stimulator cocktail (ASC) and lens-free shadow imaging technology (LSIT), using optoelectronic components. LSIT captures digital hologram images of resting and ASC-activated NK cells, while an algorithm evaluates cell size and cytoplasmic complexity using shadow parameters. The combined shadow parameter derived from the peak-to-peak distance and width standard deviation rapidly distinguishes active NK cells from inactive NK cells at the single-cell level within 30 s. Here, the feasibility of the system was demonstrated by assessing NK cells from healthy donors and immunocompromised cancer patients, demonstrating a significant difference in the innate immunity index (I3). Cancer patients showed a lower I3 value (161%) than healthy donors (326%). I3 was strongly correlated with NK cell activity measured using various markers such as interferon-gamma, tumor necrosis factor-alpha, perforin, granzyme B, and CD107a. This technology holds promise for advancing immune functional assays, offering rapid and accurate on-site analysis of NK cells, a crucial innate immune cell, with its compact and cost-effective optoelectronic setup, especially in the post-COVID-19 era.

Natural killer cell-associated prognosis model characterizes immune landscape and treatment efficacy of diffuse large B cell lymphoma

PURPOSE

NK cells are essential for the detection, identification and prediction of cancer. However, so far, there is no prognostic risk model based on NK cell-related genes to predict the prognosis and treatment outcome of DLBCL patients. This study aimed to explore a risk assessment model that could accurately predict the prognosis and treatment efficacy of DLBCL.

METHODS

Bioinformatics analysis of the expression profiles of DLBCL samples in the GEO database was performed. Cox regression and LASSO regression analysis were used to determine NK cell-related genes associated with patient's prognosis. Based on these genes, a risk assessment model was constructed to predict the prognosis of patients and the effectiveness of treatment. Finally, qRT-PCR was used to verify the expression of gene tags in clinical samples.

RESULTS

We identified seven prognosis-related NK cell-related genes (MAP2K1, PRKCB, TNFRSF10B, IL18, LAMP1, RASGRP1, and SP110), and DLBCL patients were divided into low- and high-risk groups based on these genes. Survival analysis showed that the prognosis of patients with low-risk group was better. Pathway enrichment analysis showed that the differentially expressed genes between the two risk groups were related to immune response pathways. Compared with the high-risk group, the low-risk group had higher infiltration of immune cells in tumor tissues. Besides, compared with high-risk group, low-risk patients by immunotherapy or other commonly used anti-tumor drugs might have better efficacy after treatment. In addition, qRT-PCR showed that the expression of risk genes including TNFRSF10B, IL18 and LAMP1 were significantly increased in most DLBCL samples compared to control samples, while the expression of protective genes including MAP2K1, PRKCB, RASGRP1 and SP110 were significantly decreased.

CONCLUSION

The NK cell-related gene signatures were proved to be a reliable indicator of the success of immunotherapy in patients with DLBCL, thus providing a unique evaluation method.

Potential alternatives to αβ-T cells to prevent graft-versus-host disease (GvHD) in allogeneic chimeric antigen receptor (CAR)-based cancer immunotherapy: A comprehensive review

Currently, CAR-T cell therapy relies on an individualized manufacturing process in which patient's own T cells are infused back into patients after being engineered and expanded ex vivo. Despite the astonishing outcomes of autologous CAR-T cell therapy, this approach is endowed with several limitations and drawbacks, such as high cost and time-consuming manufacturing process. Switching the armature of CAR-T cell therapy from autologous settings to allogeneic can overcome several bottlenecks of the current approach. Nevertheless, the use of allogeneic CAR-T cells is limited by the risk of life-threatening GvHD. Thus, in recent years, developing a method to move CAR-T cell therapy to allogeneic settings without the risk of GvHD has become a hot research topic in this field. Since the alloreactivity of αβ T-cell receptor (TCR) accounts for developing GvHD, several efforts have been made to disrupt endogenous TCR of allogeneic CAR-T cells using gene editing tools to prevent GvHD. Nonetheless, the off-target activity of gene editing tools and their associated genotoxicities, as well as the negative consequences of endogenous TCR disruption, are the main concerns of using this approach. As an alternative, CAR αβ-T cells can be replaced with other types of CAR-engineered cells that are capable of recognizing and killing malignant cells through CAR while avoiding the induction of GvHD. These alternatives include T cell subsets with restricted TCR repertoire (γδ-T, iNKT, virus-specific T, double negative T cells, and MAIT cells), killer cells (NK and CIK cells), non-lymphocytic cells (neutrophils and macrophages), stem/progenitor cells, and cell-free extracellular vesicles. In this review, we discuss how these alternatives can move CAR-based immunotherapy to allogeneic settings to overcome the bottlenecks of autologous manner without the risk of GvHD. We comprehensively discuss the pros and cons of these alternatives over the traditional CAR αβ-T cells in light of their preclinical studies and clinical trials.

Association between resting heart rate and low natural killer cell activity: a cross-sectional study

Resting heart rate (RHR), a simple physiological indicator, has been demonstrated to be associated with inflammation and even metabolic disorders. This study aimed to investigate whether RHR is associated with natural killer cell activity (NKA) in a large population of healthy adults using a novel assay to measure NKA. This cross-sectional study included 7,500 subjects in the final analysis. NKA was estimated by measuring the amount of interferon-gamma (IFN-γ) released by activated natural killer cells; low NKA was defined as IFN-γ level <500 pg/mL. Subjects were categorized into four groups according to RHR as follows: C1 (≤ 60 bpm), C2 (60-70 bpm), C3 (70-80 bpm), and C4 (≥ 80 bpm). Individuals with higher RHR exhibited poorer metabolic and inflammatory profiles, with the prevalence of low NKA being highest in the highest RHR category. Compared with C1 as reference, the fully adjusted odd ratios (ORs) [95% confidence intervals (CIs)] for low NKA were significantly higher in C3 (OR: 1.37, 95% CI: 1.08-1.75) and C4 (OR: 1.55, 95% CI: 1.20-2.00). In addition, RHR was shown to exert indirect effects on NKA upon consideration of the mediation effect of serum cortisol in path analysis. Our findings confirm a significant link between elevated RHR and low NKA, and suggest the usefulness of RHR, a simple indicator reflecting increased sympathetic nervous system activity and stress, in predicting reduced immune function.

Interleukin signaling in the regulation of natural killer cells biology in breast cancer

In the field of breast cancer treatment, the immunotherapy involving natural killer (NK) cells is increasingly highlighting its distinct potential and significance. Members of the interleukin (IL) family play pivotal regulatory roles in the growth, differentiation, survival, and apoptosis of NK cells, and are central to their anti-tumor activity. These cytokines enhance the ability of NK cells to recognize and eliminate tumor cells by binding to specific receptors and activating downstream signaling pathways. Furthermore, interleukins do not function in isolation; the synergistic or antagonistic interactions between different interleukins can drive NK cells toward various functional pathways, ultimately leading to diverse outcomes for breast cancer patients. This paper reviews the intricate relationship between NK cells and interleukins, particularly within the breast cancer tumor microenvironment. Additionally, we summarize the latest clinical studies and advancements in NK cell therapy for breast cancer, along with the potential applications of interleukin signaling in these therapies. In conclusion, this article underscores the critical role of NK cells and interleukin signaling in breast cancer treatment, providing valuable insights and a significant reference for future research and clinical practice.

Spatial colocalization and combined survival benefit of natural killer and CD8 T cells despite profound MHC class I loss in non-small cell lung cancer

BACKGROUND

Major histocompatibility complex class I (MHC-I) loss is frequent in non-small cell lung cancer (NSCLC) rendering tumor cells resistant to T cell lysis. NK cells kill MHC-I-deficient tumor cells, and although previous work indicated their presence at NSCLC margins, they were functionally impaired. Within, we evaluated whether NK cell and CD8 T cell infiltration and activation vary with MHC-I expression.

METHODS

We used single-stain immunohistochemistry (IHC) and Kaplan-Meier analysis to test the effect of NK cell and CD8 T cell infiltration on overall and disease-free survival. To delineate immune covariates of MHC-I-disparate lung cancers, we used multiplexed immunofluorescence (mIF) imaging followed by multivariate statistical modeling. To identify differences in infiltration and intercellular communication between IFNγ-activated and non-activated lymphocytes, we developed a computational pipeline to enumerate single-cell neighborhoods from mIF images followed by multivariate discriminant analysis.

RESULTS

Spatial quantitation of tumor cell MHC-I expression revealed intratumoral and intertumoral heterogeneity, which was associated with the local lymphocyte landscape. IHC analysis revealed that high CD56+ cell numbers in patient tumors were positively associated with disease-free survival (HR=0.58, p=0.064) and overall survival (OS) (HR=0.496, p=0.041). The OS association strengthened with high counts of both CD56+ and CD8+ cells (HR=0.199, p<1×10-3). mIF imaging and multivariate discriminant analysis revealed enrichment of both CD3+CD8+ T cells and CD3-CD56+ NK cells in MHC-I-bearing tumors (p<0.05). To infer associations of functional cell states and local cell-cell communication, we analyzed spatial single-cell neighborhood profiles to delineate the cellular environments of IFNγ+/- NK cells and T cells. We discovered that both IFNγ+ NK and CD8 T cells were more frequently associated with other IFNγ+ lymphocytes in comparison to IFNγ- NK cells and CD8 T cells (p<1×10-30). Moreover, IFNγ+ lymphocytes were most often found clustered near MHC-I+ tumor cells.

CONCLUSIONS

Tumor-infiltrating NK cells and CD8 T cells jointly affected control of NSCLC tumor progression. Coassociation of NK and CD8 T cells was most evident in MHC-I-bearing tumors, especially in the presence of IFNγ. Frequent colocalization of IFNγ+ NK cells with other IFNγ+ lymphocytes in near-neighbor analysis suggests NSCLC lymphocyte activation is coordinately regulated.

Impact of Chemotherapy on Circulating Lymphocyte Subsets in Lung Cancer Patients

Purpose

Lung cancer remains a leading cause of cancer-related death and chemotherapy stands as a fundamental component in therapy. Chemotherapy-induced myelosuppression encompasses a spectrum of hematological declines, including not only neutrophils but also lymphocytes, hemoglobin levels and platelets. This retrospective cohort study investigates alterations in peripheral blood lymphocyte subsets. By uncovering these changes, our goal is to refine patient management strategies, ensuring that the benefits of chemotherapy are maximized while minimizing its detrimental effects.

Patients and Methods

We retrospectively analyzed 159 lung cancer patients. Patients were categorized as "NT" (n=108, no previous anti-tumor therapy), and "PT" (n=51, prior therapy followed by at least a two-month treatment-free interval). Post-chemotherapy, patients were reassessed and grouped into "EarlyCycle" for those who underwent four or fewer cycles, and "LateCycle" for those who underwent more than four cycles.

Results

The study focused on analyzing the percentages of lymphocyte subsets, including T cells (CD4+, CD8+), B cells, and natural killer (NK) cells, across these groups. For T cells, the EarlyCycle group exhibited a significant increase compared to NT (0.7783 vs 0.7271; p=0.0017) and PT (0.7783 vs 0.6804; p=1.6e-05). B cells showed a significant decrease from NT to LateCycle (0.1014 vs 0.0817; p=2.2e-05) and from PT to LateCycle (0.1317 vs 0.0817; p=6.2e-10). NK cells significantly decreased in the EarlyCycle group compared to NT (0.1109 vs 0.1462; p=0.00816) and PT (0.1109 vs 0.1513; p=0.00992), with no significant change in the LateCycle group compared to either NT or PT (p>0.05).

Conclusion

Chemotherapy significantly affects lymphocyte subsets in a treatment-specific manner. The EarlyCycle group experienced a reduction in NK cell and an increase in T cell, suggesting a damage of innate immunity and an early shift towards adaptive immunity. The LateCycle group showed a substantial decrease in B cell, indicating a delayed effect on humoral immunity components.

Natural Killer cells at the frontline in the fight against cancer

Natural Killer (NK) cells are innate immune cells that play a pivotal role as first line defenders in the anti-tumor response. To prevent tumor development, NK cells are searching for abnormal cells within the body and appear to be key players in immunosurveillance. Upon recognition of abnormal cells, NK cells will become activated to destroy them. In order to fulfill their anti-tumoral function, they rely on the secretion of lytic granules, expression of death receptors and production of cytokines. Additionally, NK cells interact with other cells in the tumor microenvironment. In this review, we will first focus on NK cells' activation and cytotoxicity mechanisms as well as NK cells behavior during serial killing. Lastly, we will review NK cells' crosstalk with the other immune cells present in the tumor microenvironment.

Natural killer cells: a future star for immunotherapy of head and neck squamous cell carcinoma

The interplay between immune components and the epithelium plays a crucial role in the development and progression of head and neck squamous cell carcinoma (HNSCC). Natural killer (NK) cells, one of the main tumor-killing immune cell populations, have received increasing attention in HNSCC immunotherapy. In this review, we explore the mechanism underlying the interplay between NK cells and HNSCC. A series of immune evasion strategies utilized by cancer cells restrict HNSCC infiltration of NK cells. Overcoming these limitations can fully exploit the antineoplastic potential of NK cells. We also investigated the tumor-killing efficacy of NK cell-based immunotherapies, immunotherapeutic strategies, and new results from clinical trials. Notably, cetuximab, the most essential component of NK cell-based immunotherapy, inhibits the epidermal growth factor receptor (EGFR) signaling pathway and activates the immune system in conjunction with NK cells, inducing innate effector functions and improving patient prognosis. In addition, we compiled information on other areas for the improvement of patient prognosis using anti-EGFR receptor-based monoclonal antibody drugs and the underlying mechanisms and prognoses of new immunotherapeutic strategies for the treatment of HNSCC.

NK Cell Degranulation Triggered by Rituximab Identifies Potential Markers of Subpopulations with Enhanced Cytotoxicity toward Malignant B Cells

A promising strategy in cancer immunotherapy is to restore or enhance the cytotoxicity of NK cells, among others, by activating the mechanism of antibody-dependent cellular cytotoxicity (ADCC). Monoclonal antibodies targeting tumor antigens, such as rituximab (targeting CD20), induce NK cell-mediated ADCC and have been used to treat B cell malignancies, such as non-Hodgkin lymphoma, but not always successfully. The aim of this study was to analyze the gene expression profile of the NK cells involved in the cytolytic response stimulated by rituximab. NK cells were co-cultured with rituximab-opsonized Raji cells. Sorting into responder and non-responder groups was based on the presence of CD107a, which is a degranulation marker. RNA-seq results showed that the KIT and TNFSF4 genes were strongly down-regulated in the degranulating population of NK cells (responders); this was further confirmed by qRT-PCR. Both genes encode surface proteins with cellular signaling abilities, namely c-KIT and the OX40 ligand. Consistent with our findings, c-KIT was previously reported to correlate inversely with cytokine production by activated NK cells. The significance of these findings for cancer immunotherapy seems essential, as the pharmacological inhibition of c-KIT and OX40L, or gene ablation, could be further tested for the enhancement of the anti-tumor activity of NK cells in response to rituximab.

In-depth analysis of the interplay between oncogenic mutations and NK cell-mediated cancer surveillance in solid tumors

Natural killer (NK) cells play a crucial role in antitumoral and antiviral responses. Yet, cancer cells can alter themselves or the microenvironment through the secretion of cytokines or other factors, hindering NK cell activation and promoting a less cytotoxic phenotype. These resistance mechanisms, often referred to as the "hallmarks of cancer" are significantly influenced by the activation of oncogenes, impacting most, if not all, of the described hallmarks. Along with oncogenes, other types of genes, the tumor suppressor genes are frequently mutated or modified during cancer. Traditionally, these genes have been associated with uncontrollable tumor growth and apoptosis resistance. Recent evidence suggests oncogenic mutations extend beyond modulating cell death/proliferation programs, influencing cancer immunosurveillance. While T cells have been more studied, the results obtained highlight NK cells as emerging key protagonists for enhancing tumor cell elimination by modulating oncogenic activity. A few recent studies highlight the crucial role of oncogenic mutations in NK cell-mediated cancer recognition, impacting angiogenesis, stress ligands, and signaling balance within the tumor microenvironment. This review will critically examine recent discoveries correlating oncogenic mutations to NK cell-mediated cancer immunosurveillance, a relatively underexplored area, particularly in the era dominated by immune checkpoint inhibitors and CAR-T cells. Building on these insights, we will explore opportunities to improve NK cell-based immunotherapies, which are increasingly recognized as promising alternatives for treating low-antigenic tumors, offering significant advantages in terms of safety and manufacturing suitability.

Natural killer cells in cancer immunotherapy

Natural killer (NK) cells, as innate lymphocytes, possess cytotoxic capabilities and engage target cells through a repertoire of activating and inhibitory receptors. Particularly, natural killer group 2, member D (NKG2D) receptor on NK cells recognizes stress-induced ligands-the MHC class I chain-related molecules A and B (MICA/B) presented on tumor cells and is key to trigger the cytolytic response of NK cells. However, tumors have developed sophisticated strategies to evade NK cell surveillance, which lead to failure of tumor immunotherapy. In this paper, we summarized these immune escaping strategies, including the downregulation of ligands for activating receptors, upregulation of ligands for inhibitory receptors, secretion of immunosuppressive compounds, and the development of apoptosis resistance. Then, we focus on recent advancements in NK cell immune therapies, which include engaging activating NK cell receptors, upregulating NKG2D ligand MICA/B expression, blocking inhibitory NK cell receptors, adoptive NK cell therapy, chimeric antigen receptor (CAR)-engineered NK cells (CAR-NK), and NKG2D CAR-T cells, especially several vaccines targeting MICA/B. This review will inspire the research in NK cell biology in tumor and provide significant hope for improving cancer treatment outcomes by harnessing the potent cytotoxic activity of NK cells.

Impact of siRNA-Mediated Cofilin-1 Knockdown and Obesity Associated Microenvironment on the Motility of Natural Killer Cells

The anti-tumor capacity of natural killer (NK) cells heavily relies on their ability to migrate towards their target cells. This process is based on dynamic actinrearrangement, so-called actin treadmilling, andis tightly regulated by proteins such as cofilin-1. The aim of the present study was to identify the role of cofilin-1 (CFL-1) in the migratory behavior of NK cells and to investigate a possible impact of an obesity-associated micromilieu on these cells, as it is known that obesity correlates with various impaired NK cell functions. CFL-1 was knocked-down via transfection of NK-92 cells with respective siRNAs. Obesity associated micromilieu was mimicked by incubation of NK-92 cells with adipocyte-conditioned medium from human preadipocyte SGBS cells or leptin. Effects on CFL-1 levels, the degree of phosphorylation to the inactive pCFL-1 as well as NK-92 cell motility were analyzed. Surprisingly, siRNA-mediated CFL-1 knockdown led to a significant increase of migration, as determined by enhanced velocity and accumulated distance of migration. No effect on CFL-1 nor pCFL-1 expression levels, proportion of phosphorylation and cell migratory behavior could be demonstrated under the influence of an obesity-associated microenvironment. In conclusion, the results indicate a significant effect of a CFL-1 knockdown on NK cell motility.

Spatial colocalization and combined survival benefit of natural killer and CD8 T cells despite profound MHC class I loss in non-small cell lung cancer

Background

MHC class I (MHC-I) loss is frequent in non-small cell lung cancer (NSCLC) rendering tumor cells resistant to T cell lysis. NK cells kill MHC-I-deficient tumor cells, and although previous work indicated their presence at NSCLC margins, they were functionally impaired. Within, we evaluated whether NK cell and CD8 T cell infiltration and activation vary with MHC-I expression.

Methods

We used single-stain immunohistochemistry (IHC) and Kaplan-Meier analysis to test the effect of NK cell and CD8 T cell infiltration on overall and disease-free survival. To delineate immune covariates of MHC-I-disparate lung cancers, we used multiplexed immunofluorescence (mIF) imaging followed by multivariate statistical modeling. To identify differences in infiltration and intercellular communication between IFNγ-activated and non-activated lymphocytes, we developed a computational pipeline to enumerate single cell neighborhoods from mIF images followed by multivariate discriminant analysis.

Results

Spatial quantitation of tumor cell MHC-I expression revealed intra- and inter-tumoral heterogeneity, which was associated with the local lymphocyte landscape. IHC analysis revealed that high CD56+ cell numbers in patient tumors were positively associated with disease-free survival (DFS) (HR=0.58, p=0.064) and overall survival (OS) (HR=0.496, p=0.041). The OS association strengthened with high counts of both CD56+ and CD8+ cells (HR=0.199, p<1×10-3). mIF imaging and multivariate discriminant analysis revealed enrichment of both CD3+CD8+ T cells and CD3-CD56+ NK cells in MHC-I-bearing tumors (p<0.05). To infer associations of functional cell states and local cell-cell communication, we analyzed spatial single cell neighborhood profiles to delineate the cellular environments of IFNγ+/- NK cells and T cells. We discovered that both IFNγ+ NK and CD8 T cells were more frequently associated with other IFNγ+ lymphocytes in comparison to IFNγ- NK cells and CD8 T cells (p<1×10-30). Moreover, IFNγ+ lymphocytes were most often found clustered near MHC-I+ tumor cells.

Conclusions

Tumor-infiltrating NK cells and CD8 T cells jointly affected control of NSCLC tumor progression. Co-association of NK and CD8 T cells was most evident in MHC-I-bearing tumors, especially in the presence of IFNγ. Frequent co-localization of IFNγ+ NK cells with other IFNγ+ lymphocytes in near-neighbor analysis suggests NSCLC lymphocyte activation is coordinately regulated.

Exploring the Potential of Natural Killer Cell-Based Immunotherapy in Targeting High-Grade Serous Ovarian Carcinomas

High-grade serous ovarian cancers (HGSOCs) likely consist of poorly differentiated stem-like cells (PDSLCs) and differentiated tumor cells. Conventional therapeutics are incapable of completely eradicating PDSLCs, contributing to disease progression and tumor relapse. Primary NK cells are known to effectively lyse PDSLCs, but they exhibit low or minimal cytotoxic potential against well-differentiated tumors. We have introduced and discussed the characteristics of super-charged NK (sNK) cells in this review. sNK cells, in comparison to primary NK cells, exhibit a significantly higher capability for the direct killing of both PDSLCs and well-differentiated tumors. In addition, sNK cells secrete significantly higher levels of cytokines, especially those known to induce the differentiation of tumors. In addition, we propose that a combination of sNK and chemotherapy could be one of the most effective strategies to eliminate the heterogeneous population of ovarian tumors; sNK cells can lyse both PDSLCs and well-differentiated tumors, induce the differentiation of PDSLCs, and could be used in combination with chemotherapy to target both well-differentiated and NK-induced differentiated tumors.

Current and future immunotherapeutic approaches in pancreatic cancer treatment

Pancreatic cancer is a major cause of cancer-related death, but despondently, the outlook and prognosis for this resistant type of tumor have remained grim for a long time. Currently, it is extremely challenging to prevent or detect it early enough for effective treatment because patients rarely exhibit symptoms and there are no reliable indicators for detection. Most patients have advanced or spreading cancer that is difficult to treat, and treatments like chemotherapy and radiotherapy can only slightly prolong their life by a few months. Immunotherapy has revolutionized the treatment of pancreatic cancer, yet its effectiveness is limited by the tumor's immunosuppressive and hard-to-reach microenvironment. First, this article explains the immunosuppressive microenvironment of pancreatic cancer and highlights a wide range of immunotherapy options, including therapies involving oncolytic viruses, modified T cells (T-cell receptor [TCR]-engineered and chimeric antigen receptor [CAR] T-cell therapy), CAR natural killer cell therapy, cytokine-induced killer cells, immune checkpoint inhibitors, immunomodulators, cancer vaccines, and strategies targeting myeloid cells in the context of contemporary knowledge and future trends. Lastly, it discusses the main challenges ahead of pancreatic cancer immunotherapy.

Memory-like differentiation enhances NK cell responses against colorectal cancer

Metastatic (m) colorectal cancer (CRC) is an incurable disease with a poor prognosis and thus remains an unmet clinical need. Immune checkpoint blockade (ICB)-based immunotherapy is effective for mismatch repair-deficient (dMMR)/microsatellite instability-high (MSI-H) mCRC patients, but it does not benefit the majority of mCRC patients. NK cells are innate lymphoid cells with potent effector responses against a variety of tumor cells but are frequently dysfunctional in cancer patients. Memory-like (ML) NK cells differentiated after IL-12/IL-15/IL-18 activation overcome many challenges to effective NK cell anti-tumor responses, exhibiting enhanced recognition, function, and in vivo persistence. We hypothesized that ML differentiation enhances the NK cell responses to CRC. Compared to conventional (c) NK cells, ML NK cells displayed increased IFN-γ production against both CRC cell lines and primary patient-derived CRC spheroids. ML NK cells also exhibited improved killing of CRC target cells in vitro in short-term and sustained cytotoxicity assays, as well as in vivo in NSG mice. Mechanistically, enhanced ML NK cell responses were dependent on the activating receptor NKG2D as its blockade significantly decreased ML NK cell functions. Compared to cNK cells, ML NK cells exhibited greater antibody-dependent cytotoxicity when targeted against CRC by cetuximab. ML NK cells from healthy donors and mCRC patients exhibited increased anti-CRC responses. Collectively, our findings demonstrate that ML NK cells exhibit enhanced responses against CRC targets, warranting further investigation in clinical trials for mCRC patients, including those who have failed ICB.

No time to die: Epigenetic regulation of natural killer cell survival

NK cells are short-lived innate lymphocytes that can mediate antigen-independent responses to infection and cancer. However, studies from the past two decades have shown that NK cells can acquire transcriptional and epigenetic modifications during inflammation that result in increased survival and lifespan. These findings blur the lines between the innate and adaptive arms of the immune system, and suggest that the homeostatic mechanisms that govern the persistence of innate immune cells are malleable. Indeed, recent studies have shown that NK cells undergo continuous and strictly regulated adaptations controlling their survival during development, tissue residency, and following inflammation. In this review, we summarize our current understanding of the critical factors regulating NK cell survival throughout their lifespan, with a specific emphasis on the epigenetic modifications that regulate the survival of NK cells in various contexts. A precise understanding of the molecular mechanisms that govern NK cell survival will be important to enhance therapies for cancer and infectious diseases.

Exploring natural killer cell-related biomarkers in multiple myeloma: a novel nature killer cell-related model predicting prognosis and immunotherapy response using single-cell study

BACKGROUND

Natural killer cells (NKs) may be involved in multiple myeloma (MM) progression. The present study elucidated the correlation between NKs and the progression of MM using single-cell binding transcriptome probes to identify NK cell-related biomarkers.

METHODS

Single-cell analysis was performed including cell and subtype annotation, cell communication, and pseudotime analysis. Hallmark pathway enrichment analysis of NKs and NKs-related differentially expressed genes (DEGs) were conducted using Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and protein-protein interaction (PPI) networks. Then, a risk model was structured based on biomarkers identified through univariate Cox regression analysis and least absolute shrinkage and selection operator regression analysis and subsequently validated. Additionally, correlation of clinical characteristics, gene set enrichment analysis, immune analysis, regulatory network, and drug forecasting were explored.

RESULTS

A total of 13 cell clusters were obtained and annotated, including 8 cell populations that consisted of NKs. Utilizing 123 PPI network node genes, 8 NK-related DEGs were selected to construct a prognostic model. Immune cell infiltration results suggested that 11 immune cells exhibited marked differences in the high and low-risk groups. Finally, the model was used to screen potential drug targets to enhance immunotherapy efficacy.

CONCLUSION

A new prognostic model for MM associated with NKs was constructed and validated. This model provides a fresh perspective for predicting patient outcomes, immunotherapeutic response, and candidate drugs.

Distinct CD16a features on human NK cells observed by flow cytometry correlate with increased ADCC

Natural killer (NK) cells destroy tissue that have been opsonized with antibodies. Strategies to generate or identify cells with increased potency are expected to enhance NK cell-based immunotherapies. We previously generated NK cells with increased antibody-dependent cell mediated cytotoxicity (ADCC) following treatment with kifunensine, an inhibitor targeting mannosidases early in the N-glycan processing pathway. Kifunensine treatment also increased the antibody-binding affinity of Fc γ receptor IIIa/CD16a. Here we demonstrate that inhibiting NK cell N-glycan processing increased ADCC. We reduced N-glycan processing with the CRIPSR-CAS9 knockdown of MGAT1, another early-stage N-glycan processing enzyme, and showed that these cells likewise increased antibody binding affinity and ADCC. These experiments led to the observation that NK cells with diminished N-glycan processing capability also revealed a clear phenotype in flow cytometry experiments using the B73.1 and 3G8 antibodies binding two distinct CD16a epitopes. We evaluated this "affinity profiling" approach using primary NK cells and identified a distinct shift and differentiated populations by flow cytometry that correlated with increased ADCC.

Integrated analysis of single-cell and bulk RNA-sequencing reveals a novel signature based on NK cell marker genes to predict prognosis and immunotherapy response in gastric cancer

Natural killer (NK) cells play essential roles in the tumor development, diagnosis, and prognosis of tumors. In this study, we aimed to establish a reliable signature based on marker genes in NK cells, thus providing a new perspective for assessing immunotherapy and the prognosis of patients with gastric cancer (GC). We analyzed a total of 1560 samples retrieved from the public database. We performed a comprehensive analysis of single-cell RNA-sequencing (scRNA-seq) data of gastric cancer and identified 377 marker genes for NK cells. By performing Cox regression analysis, we established a 12-gene NK cell-associated signature (NKCAS) for the Cancer Genome Atlas (TCGA) cohort, that assigned GC patients into a low-risk group (LRG) or a high-risk group (HRG). In the TCGA cohort, the areas under curve (AUC) value were 0.73, 0.81, and 0.80 at 1, 3, and 5 years. External validation of the predictive ability for the signature was then validated in the Gene Expression Omnibus (GEO) cohorts (GSE84437). The expression levels of signature genes were measured and validated in GC cell lines by real-time PCR. Moreover, NKCAS was identified as an independent prognostic factor by multivariate analysis. We combined this with a variety of clinicopathological characteristics (age, M stage, and tumor grade) to construct a nomogram to predict the survival outcomes of patients. Moreover, the LRG showed higher immune cell infiltration, especially CD8+ T cells and NK cells. The risk score was negatively associated with inflammatory activities. Importantly, analysis of the independent immunotherapy cohort showed that the LRG had a better prognosis and immunotherapy response when compared with the HRG. The identification of NK cell marker genes in this study suggests potential therapeutic targets. Additionally, the developed predictive signatures and nomograms may aid in the clinical management of GC.

Roles of reactive oxygen species in inflammation and cancer

Reactive oxygen species (ROS) constitute a spectrum of oxygenic metabolites crucial in modulating pathological organism functions. Disruptions in ROS equilibrium span various diseases, and current insights suggest a dual role for ROS in tumorigenesis and the immune response within cancer. This review rigorously examines ROS production and its role in normal cells, elucidating the subsequent regulatory network in inflammation and cancer. Comprehensive synthesis details the documented impacts of ROS on diverse immune cells. Exploring the intricate relationship between ROS and cancer immunity, we highlight its influence on existing immunotherapies, including immune checkpoint blockade, chimeric antigen receptors, and cancer vaccines. Additionally, we underscore the promising prospects of utilizing ROS and targeting ROS modulators as novel immunotherapeutic interventions for cancer. This review discusses the complex interplay between ROS, inflammation, and tumorigenesis, emphasizing the multifaceted functions of ROS in both physiological and pathological conditions. It also underscores the potential implications of ROS in cancer immunotherapy and suggests future research directions, including the development of targeted therapies and precision oncology approaches. In summary, this review emphasizes the significance of understanding ROS-mediated mechanisms for advancing cancer therapy and developing personalized treatments.

Engineering immune response to regulate cardiovascular disease and cancer

Cardiovascular disease (CVD) and cancer are major contributors to global morbidity and mortality. This book chapter delves into the intricate relationship between the immune system and the pathogenesis of both cardiovascular and cancer diseases, exploring the roles of innate and adaptive immunities, immune regulation, and immunotherapy in these complex conditions. The innate immune system acts as the first line of defense against tissue damage and infection, with a significant impact on the initiation and progression of CVD and cancer. Endothelial dysfunction, a hallmark in CVD, shares commonalities with the tumor microenvironment in cancer, emphasizing the parallel involvement of the immune system in both conditions. The adaptive immune system, particularly T cells, contributes to prolonged inflammation in both CVD and cancer. Regulatory T cells and the intricate balance between different T cell subtypes influence disease progression, wound healing, and the outcomes of ischemic injury and cancer immunosurveillance. Dysregulation of immune homeostasis can lead to chronic inflammation, contributing to the development and progression of both CVD and cancer. Thus, immunotherapy emerged as a promising avenue for preventing and managing these diseases, with strategies targeting immune cell modulation, cytokine manipulation, immune checkpoint blockade, and tolerance induction. The impact of gut microbiota on CVD and cancer too is explored in this chapter, highlighting the role of gut leakiness, microbial metabolites, and the potential for microbiome-based interventions in cardiovascular and cancer immunotherapies. In conclusion, immunomodulatory strategies and immunotherapy hold promise in reshaping the landscape of cardiovascular and cancer health. Additionally, harnessing the gut microbiota for immune modulation presents a novel approach to prevent and manage these complex diseases, emphasizing the importance of personalized and precision medicine in healthcare. Ongoing research and clinical trials are expected to further elucidate the complex immunological underpinnings of CVD and cancer thereby refining these innovative approaches.

Safety, efficacy and determinants of response of allogeneic CD19-specific CAR-NK cells in CD19+ B cell tumors: a phase 1/2 trial

There is a pressing need for allogeneic chimeric antigen receptor (CAR)-immune cell therapies that are safe, effective and affordable. We conducted a phase 1/2 trial of cord blood-derived natural killer (NK) cells expressing anti-CD19 chimeric antigen receptor and interleukin-15 (CAR19/IL-15) in 37 patients with CD19+ B cell malignancies. The primary objectives were safety and efficacy, defined as day 30 overall response (OR). Secondary objectives included day 100 response, progression-free survival, overall survival and CAR19/IL-15 NK cell persistence. No notable toxicities such as cytokine release syndrome, neurotoxicity or graft-versus-host disease were observed. The day 30 and day 100 OR rates were 48.6% for both. The 1-year overall survival and progression-free survival were 68% and 32%, respectively. Patients who achieved OR had higher levels and longer persistence of CAR-NK cells. Receiving CAR-NK cells from a cord blood unit (CBU) with nucleated red blood cells ≤ 8 × 107 and a collection-to-cryopreservation time ≤ 24 h was the most significant predictor for superior outcome. NK cells from these optimal CBUs were highly functional and enriched in effector-related genes. In contrast, NK cells from suboptimal CBUs had upregulation of inflammation, hypoxia and cellular stress programs. Finally, using multiple mouse models, we confirmed the superior antitumor activity of CAR/IL-15 NK cells from optimal CBUs in vivo. These findings uncover new features of CAR-NK cell biology and underscore the importance of donor selection for allogeneic cell therapies. ClinicalTrials.gov identifier: NCT03056339 .