Hydrogel activation of Mincle receptors for tumor cell processing: A novel approach in cancer immunotherapy.

An obstacle in current tumor immunotherapies lies in the challenge of achieving sustained and tumor-targeting T cell immunity, impeded by the limited antigen processing and cross-presentation of tumor antigens. Here, we propose a hydrogel-based multicellular immune factory within the body that autonomously converts tumor cells into an antitumor vaccine. Within the body, the scaffold, formed by a calcium-containing chitosan hydrogel complex (ChitoCa) entraps tumor cells and attracts immune cells to establish a durable and multicellular microenvironment. Within this context, tumor cells are completely eliminated by antigen-presenting cells (APCs) and processed for cross-antigen presentation. The regulatory mechanism relies on the Mincle receptor, a cell-phagocytosis-inducing C-type lectin receptor specifically activated on ChitoCa-recruited APCs, which serves as a recognition synapse, facilitating a tenfold increase in tumor cell engulfment and subsequent elimination. The ChitoCa-induced tumor cell processing further promotes the cross-presentation of tumor antigens to prime protective CD8+ T cell responses. Therefore, the ChitoCa treatment establishes an immune niche within the tumor microenvironment, resulting in effective tumor regression either used alone or in combination with other immunotherapies. This hydrogel-induced immune factory establishes a functional organ-like multicellular colony for tumor-specific immunotherapy, paving the way for innovative strategies in cancer treatment.

Shaping immune landscape of colorectal cancer by cholesterol metabolites.

Cancer immunotherapies have achieved unprecedented success in clinic, but they remain largely ineffective in some major types of cancer, such as colorectal cancer with microsatellite stability (MSS CRC). It is therefore important to study tumor microenvironment of resistant cancers for developing new intervention strategies. In this study, we identify a metabolic cue that determines the unique immune landscape of MSS CRC. Through secretion of distal cholesterol precursors, which directly activate RORγt, MSS CRC cells can polarize T cells toward Th17 cells that have well-characterized pro-tumor functions in colorectal cancer. Analysis of large human cancer cohorts revealed an asynchronous pattern of the cholesterol biosynthesis in MSS CRC, which is responsible for the abnormal accumulation of distal cholesterol precursors. Inhibiting the cholesterol biosynthesis enzyme Cyp51, by pharmacological or genetic interventions, reduced the levels of intratumoral distal cholesterol precursors and suppressed tumor progression through a Th17-modulation mechanism in preclinical MSS CRC models. Our study therefore reveals a novel mechanism of cancer-immune interaction and an intervention strategy for the difficult-to-treat MSS CRC.

Gasdermin D-mediated pyroptosis is regulated by AMPK-mediated phosphorylation in tumor cells.

Gasdermin D (GSDMD) is a critical mediator of pyroptosis, which consists of a N-terminal pore-forming domain and a C-terminal autoinhibitory domain. Its cytolytic activity is sequestered by the intramolecular autoinhibitory mechanism. Upon caspase-1/11 mediated cleavage of GSDMD, the N-terminal pore-forming domain (GD-NT) is released to mediate pyroptosis. However, it remains unclear how GD-NT is regulated once it is generated. In the current study, we developed a TetOn system in which GD-NT was selectively induced in tumor cells to explore how the cytolytic activity of GD-NT is regulated. We found that the cytolytic activity of GD-NT was negatively regulated by the AMP-activated protein kinase (AMPK) and AMPK activation rendered tumor cells resistant to GD-NT-mediated pyroptosis. Mechanistically, AMPK phosphorylated GD-NT at the serine 46 (pS46-GD), which altered GD-NT oligomerization and subsequently eliminated its pore-forming ability. In our in vivo tumor model, AMPK-mediated phosphorylation abolished GD-NT-induced anti-tumor activity and resulted in an aggressive tumor growth. Thus, our data demonstrate the critical role of AMPK in negatively regulating the cytolytic activity of GD-NT. Our data also highlight an unexpected link between GSDMD-mediated pyroptosis and the AMPK signaling pathway in certain tumor cells.

The unique expression pattern of human leukocyte antigen in trophoblasts potentially explains the key mechanism of maternal-fetal tolerance and successful pregnancy.

The success of pregnancy mainly depends on immune tolerance of the mother for the semi-allogeneic fetus. The placenta carrying paternal antigens develops in the maternal uterus without suffering immune attack, making the underlying mechanism of maternal tolerance an enduring mystery. As we all know, human leukocyte antigen (HLA) plays an important role in antigen processing and presentation, thus inducing specific immune responses. Therefore, it is reasonable to speculate that the absence of classical HLA class-I（HLA-I) and HLA class-II (HLA-II) molecules in trophoblasts may account for the maternal-fetal tolerance. Here, we review the HLA-involved interactions between trophoblast cells and decidual immune cells, which contribute to the immunotolerance in the development of normal pregnancy. We also compare the similarity between the maternal-fetal interface and tumor-immune microenvironment because the important role of HLA molecules in tumor immune invasion can provide some references to studies of maternal-fetal immune tolerance. Besides, the abnormal HLA expression is likely to be associated with unexplained miscarriage, making HLA molecules potential therapeutic targets. The advances reported by these studies may exert profound influences on other research areas, including tumor immunity, organ transplantation and autoimmune disease in the future.

Exhaustion-associated cholesterol deficiency dampens the cytotoxic arm of antitumor immunity.

The concept of targeting cholesterol metabolism to treat cancer has been widely tested in clinics, but the benefits are modest, calling for a complete understanding of cholesterol metabolism in intratumoral cells. We analyze the cholesterol atlas in the tumor microenvironment and find that intratumoral T cells have cholesterol deficiency, while immunosuppressive myeloid cells and tumor cells display cholesterol abundance. Low cholesterol levels inhibit T cell proliferation and cause autophagy-mediated apoptosis, particularly for cytotoxic T cells. In the tumor microenvironment, oxysterols mediate reciprocal alterations in the LXR and SREBP2 pathways to cause cholesterol deficiency of T cells, subsequently leading to aberrant metabolic and signaling pathways that drive T cell exhaustion/dysfunction. LXRß depletion in chimeric antigen receptor T (CAR-T) cells leads to improved antitumor function against solid tumors. Since T cell cholesterol metabolism and oxysterols are generally linked to other diseases, the new mechanism and cholesterol-normalization strategy might have potential applications elsewhere.

Immunogenetic Metabolomics Reveals Key Enzymes That Modulate CAR T-cell Metabolism and Function.

Immune evasion is a critical step of cancer progression that remains a major obstacle for current T cell-based immunotherapies. Hence, we investigated whether it is possible to genetically reprogram T cells to exploit a common tumor-intrinsic evasion mechanism whereby cancer cells suppress T-cell function by generating a metabolically unfavorable tumor microenvironment (TME). In an in silico screen, we identified ADA and PDK1 as metabolic regulators. We then showed that overexpression (OE) of these genes enhanced the cytolysis of CD19-specific chimeric antigen receptor (CAR) T cells against cognate leukemia cells, and conversely, ADA or PDK1 deficiency dampened this effect. ADA-OE in CAR T cells improved cancer cytolysis under high concentrations of adenosine, the ADA substrate, and an immunosuppressive metabolite in the TME. High-throughput transcriptomics and metabolomics analysis of these CAR T cells revealed alterations of global gene expression and metabolic signatures in both ADA- and PDK1-engineered CAR T cells. Functional and immunologic analyses demonstrated that ADA-OE increased proliferation and decreased exhaustion in CD19-specific and HER2-specific CAR T cells. ADA-OE improved tumor infiltration and clearance by HER2-specific CAR T cells in an in vivo colorectal cancer model. Collectively, these data unveil systematic knowledge of metabolic reprogramming directly in CAR T cells and reveal potential targets for improving CAR T-cell therapy.

Clinical outcomes of clip-assisted endoscopic cyanoacrylate injection versus conventional endoscopic cyanoacrylate injection in treating gastric varices with a gastrorenal shunt.

BACKGROUND AND STUDY AIMS: The optimal treatment for gastric varices (GVs) is a topic that remains definite for this study. This study compared the clinical outcomes of clip-assisted endoscopic cyanoacrylate injection (clip-ECI) to conventional endoscopic cyanoacrylate injection (con-ECI) for the treatment of GVs with a gastrorenal shunt. PATIENTS AND METHODS: Data were collected retrospectively in five medical centers from 2015 to 2020. The patients were treated with con-ECI (n = 126) or clip-ECI (n = 148). Clinical characteristics and procedural outcomes were compared. Patients were followed until death, liver transplantation or 6 months after the treatment. The primary outcome was rebleeding, and the secondary outcome was survival. RESULTS: There were no significant differences in age, sex, etiology, shunt diameter and Child-Pugh classification between the two groups. Fewer GVs obliteration sessions were required in the clip-ECI group than in the con-ECI group (p = 0.015). The cumulative 6-month rebleeding-free rates were 88.6% in the clip-ECI group and 73.7% in the con-ECI group (p = 0.002). The cumulative 6-month survival rates were 97.1% in the clip-ECI group and 94.8% in the con-ECI group (p = 0.378). CONCLUSIONS: Compared with con-ECI, clip-ECI appears more effective for the treatment of GVs with a gastrorenal shunt, which required less sessions and achieved a higher 6-month rebleeding-free rate.

Percutaneous transhepatic intraportal biopsy using gastroscope biopsy forceps for diagnosis of a pancreatic neuroendocrine neoplasm: A case report.

BACKGROUND: Pancreatic neuroendocrine neoplasms (PNENs) are a rare group of neoplasms originating from the islets of the Langerhans. Portal vein tumor thrombosis has been reported in 33% of patients with PNENs. While the histopathological diagnosis of PNENs is usually based on percutaneous biopsy or endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), these approaches may be impeded by gastric varices, poor access windows, or anatomically contiguous critical structures. Obtaining a pathological diagnosis using a gastroscope biopsy forceps via percutaneous transhepatic intravascular pathway is an innovative method that has rarely been reported. CASE SUMMARY: A 72-year-old man was referred to our hospital for abdominal pain and melena. Abdominal contrast-enhanced magnetic resonance imaging revealed a well-enhanced tumor (size: 2.4 cm × 1.2 cm × 1.2 cm) in the pancreatic tail with portal vein invasion. Traditional pathological diagnosis via EUS-FNA was not possible because of diffuse gastric varices. We performed a percutaneous transportal biopsy of the portal vein tumor thrombus using a gastroscope biopsy forceps. Histopathologic examination revealed a pancreatic neuroendocrine neoplasm (G2) with somatostatin receptors 2 (+), allowing systemic treatment. CONCLUSION: Intravascular biopsy using gastroscope biopsy forceps appears to be a safe and effective method for obtaining a histopathological diagnosis. Although well-designed clinic trials are required to obtain more definitive evidence, this procedure may help improve the diagnosis of portal vein thrombosis and related diseases.

Immunogenetic metabolomics revealed key enzymes that modulate CAR-T metabolism and function.

Immune evasion is a critical step of cancer progression that remains a major obstacle for current T cell-based immunotherapies. Hence, we seek to genetically reprogram T cells to exploit a common tumor-intrinsic evasion mechanism, whereby cancer cells suppress T cell function by generating a metabolically unfavorable tumor microenvironment (TME). Specifically, we use an in silico screen to identify ADA and PDK1 as metabolic regulators, in which gene overexpression (OE) enhances the cytolysis of CD19-specific CD8 CAR-T cells against cognate leukemia cells, and conversely, ADA or PDK1 deficiency dampens such effect. ADA -OE in CAR-T cells improves cancer cytolysis under high concentrations of adenosine, the ADA substrate and an immunosuppressive metabolite in the TME. High-throughput transcriptomics and metabolomics in these CAR-Ts reveal alterations of global gene expression and metabolic signatures in both ADA- and PDK1- engineered CAR-T cells. Functional and immunological analyses demonstrate that ADA -OE increases proliferation and decreases exhaustion in α-CD19 and α-HER2 CAR-T cells. ADA-OE improves tumor infiltration and clearance by α-HER2 CAR-T cells in an in vivo colorectal cancer model. Collectively, these data unveil systematic knowledge of metabolic reprogramming directly in CAR-T cells, and reveal potential targets for improving CAR-T based cell therapy. Synopsis: The authors identify the adenosine deaminase gene (ADA) as a regulatory gene that reprograms T cell metabolism. ADA-overexpression (OE) in α-CD19 and α-HER2 CAR-T cells increases proliferation, cytotoxicity, memory, and decreases exhaustion, and ADA-OE α-HER2 CAR-T cells have enhanced clearance of HT29 human colorectal cancer tumors in vivo .

Hepatocyte-derived exosomes deliver H2AFJ to hepatic stellate cells and promote liver fibrosis via the MAPK/STMN1 axis activation.

Hepatic stellate cells (HSCs) activate and acquire proliferative features in response to liver injury. However, mechanisms involved in the activation of fibrotic HSCs remain uncharacterized. This study aims at elaborating the mechanistic basis by which exosomal H2AFJ derived from hepatocytes might affect the activation of HSCs and liver fibrosis. Bioinformatics analysis based on transcriptomic RNA-seq data was used to screen out the downstream regulatory genes and pathways of H2AFJ. Mouse hepatocytes AML-12 cells were stimulated with CCl4 to mimic an in vitro microenvironment of liver fibrosis, from which exosomes were isolated. Next, HSCs were co-cultured with hepatocyte-derived exosomes followed by detection of HSC migration and invasion in the presence of manipulated H2AFJ and STMN1 expression and MAPK pathway inhibitor. It was found that H2AFJ was highly expressed in hepatocyte-derived exosomes after CCl4 stimulation. Hepatocyte-derived exosomal H2AFJ promoted HSC migration and invasion. H2AFJ upregulated c-jun-mediated STMN1 by activating the MAPK signaling pathway. Furthermore, in vivo experiments verified that silencing of H2AFJ attenuated liver fibrosis in mice, while restoration of STMN1 negated its effect. Collectively, hepatocyte-derived exosomal H2AFJ aggravated liver fibrosis by activating the MAPK/STMN1 signaling pathway. This study provides a potential therapeutic target for alleviating liver fibrosis.

Enhancing Natural Killer Cell-Mediated Cancer Immunotherapy by the Biological Macromolecule Nocardia rubra Cell-Wall Skeleton.

The biological macromolecule Nocardia rubra cell-wall skeleton (Nr-CWS) has well-established immune-stimulating and anti-tumor activities. However, the role of Nr-CWS on natural killer (NK) cells remains unclear. Here, we explore the function and related mechanisms of Nr-CWS on NK cells. Using a tumor-bearing model, we show that Nr-CWS has slightly effect on solid tumor. In addition, using a tumor metastasis model, we show that Nr-CWS suppresses the lung metastasis induced by B16F10 melanoma cells in mice, which indicates that Nr-CWS may up-regulate the function of NK cells. Further investigation demonstrated that Nr-CWS can increase the expression of TRAIL and FasL on spleen NK cells from Nr-CWS treated B16F10 tumor metastasis mice. The spleen index and serum levels of TNF-α, IFN-γ, and IL-2 in B16F10 tumor metastasis mice treated with Nr-CWS were significantly increased. In vitro, the studies using purified or sorted NK cells revealed that Nr-CWS increases the expression of CD69, TRAIL, and FasL, decreases the expression of CD27, and enhances NK cell cytotoxicity. The intracellular expression of IFN-γ, TNF-α, perforin (prf), granzyme-B (GrzB), and secreted TNF-α, IFN-γ, IL-6 of the cultured NK cells were significantly increased after treatment with Nr-CWS. Overall, the findings indicate that Nr-CWS could suppress the lung metastasis induced by B16F10 melanoma cells, which may be exerted through its effect on NK cells by promoting NK cell terminal differentiation (CD27lowCD11bhigh), and up-regulating the production of cytokines and cytotoxic molecules.

Optimal time point of response assessment for predicting survival is associated with tumor burden in hepatocellular carcinoma receiving repeated transarterial chemoembolization.

OBJECTIVES: Objective response rate (ORR) under mRECIST criteria after transarterial chemoembolization (TACE) is a well-perceived surrogate endpoint of overall survival (OS). However, its optimal time point remains controversial and may be influenced by tumor burden. We aim to investigate the surrogacy of initial/best ORR in relation to tumor burden. METHODS: A total of 1549 eligible treatment-naïve patients with unresectable hepatocellular carcinoma (HCC), Child-Pugh score ≤ 7, and performance status score ≤ 1 undergoing TACE between January 2010 and May 2016 from 17 academic hospitals were retrospectively analyzed. Based on "six-and-twelve" criteria, tumor burden was graded as low, intermediate, and high if the sum of the maximum tumor diameter and tumor number was ≤ 6, > 6 but ≤ 12, and > 12, respectively. RESULTS: Both initial and best ORRs interacted with tumor burden. Initial and best ORRs could equivalently predict and correlate with OS in low (adjusted HR, 2.55 and 2.95, respectively, both p < 0.001; R = 0.84, p = 0.035, and R = 0.97, p = 0.002, respectively) and intermediate strata (adjusted HR, 1.81 and 2.22, respectively, both p < 0.001; R = 0.74, p = 0.023, and R = 0.9, p = 0.002, respectively). For high strata, only best ORR exhibited qualified surrogacy (adjusted HR, 2.61, p < 0.001; R = 0.70, p = 0.035), whereas initial ORR was not significant (adjusted HR, 1.08, p = 0.357; R = 0.22, p = 0.54). CONCLUSIONS: ORR as surrogacy of OS is associated with tumor burden. For patients with low/intermediate tumor burden, initial ORR should be preferred in its early availability upon similar sensitivity, whereas for patients with high tumor burden, best ORR has optimal sensitivity. Timing of OR assessment should be tailored according to tumor burden. KEY POINTS: • This is the first study utilizing individual patient data to comprehensively analyze the surrogacy of ORR with a long follow-up period. • Optimal timing of ORR assessment for predicting survival should be tailored according to tumor burden. • For patients with low and intermediate tumor burden, initial ORR is optimal for its timeliness upon similar sensitivity with best ORR. For patients with high tumor burden, best ORR has optimal sensitivity.

A genome-scale gain-of-function CRISPR screen in CD8 T cells identifies proline metabolism as a means to enhance CAR-T therapy.

Chimeric antigen receptor (CAR)-T cell-based immunotherapy for cancer and immunological diseases has made great strides, but it still faces multiple hurdles. Finding the right molecular targets to engineer T cells toward a desired function has broad implications for the armamentarium of T cell-centered therapies. Here, we developed a dead-guide RNA (dgRNA)-based CRISPR activation screen in primary CD8+ T cells and identified gain-of-function (GOF) targets for CAR-T engineering. Targeted knockin or overexpression of a lead target, PRODH2, enhanced CAR-T-based killing and in vivo efficacy in multiple cancer models. Transcriptomics and metabolomics in CAR-T cells revealed that augmenting PRODH2 expression reshaped broad and distinct gene expression and metabolic programs. Mitochondrial, metabolic, and immunological analyses showed that PRODH2 engineering enhances the metabolic and immune functions of CAR-T cells against cancer. Together, these findings provide a system for identification of GOF immune boosters and demonstrate PRODH2 as a target to enhance CAR-T efficacy.

Pocket-creation method versus conventional method of endoscopic submucosal dissection for superficial colorectal neoplasms: a meta-analysis.

BACKGROUND AND AIMS: The pocket-creation method (PCM) is a newly developed strategy for colorectal endoscopic submucosal dissection (ESD). However, its superiority over the conventional method (CM) has not been established. The aim of this meta-analysis was to evaluate the efficacy and safety of PCM-ESD compared with CM-ESD for superficial colorectal neoplasms (SCNs). METHODS: Literature searches were conducted using the Pubmed, Embase, and Cochrane Library databases, and a meta-analysis was performed. The primary outcome was the R0 resection rate, and the secondary outcomes were the en bloc resection rate, dissection speed, procedure time, and adverse event rate. RESULTS: Five studies (2 randomized controlled trials and 3 retrospective studies) with 1481 patients were included in our meta-analysis. The pooled analysis showed that PCM-ESD achieved a higher R0 resection rate (93.5% vs 78.1%; odds ratio [OR], 3.4; 95% confidence interval [CI], 1.3-8.9; I2 = 58%), a higher en bloc resection rate (99.8% vs 92.8%; OR, 9.9; 95% CI, 2.7-36.2; I2 = 0), a shorter procedure time (minutes) (mean difference [MD], -11.5; 95% CI, -19.9 to -3.1; I2 = 72%), a faster dissection speed (mm2/min) (MD, 3.6; 95% CI, 2.8-4.5; I2 = 0), and a lower overall adverse event rate (4.4% vs 6.6%; OR, 0.6; 95% CI, 0.3-1.0; I2 = 0) compared with CM-ESD. CONCLUSIONS: This meta-analysis showed that PCM-ESD improves the efficacy and safety compared with CM-ESD for superficial colorectal neoplasms.

Long noncoding RNA LBX2-AS1-modulated miR-4766-5p regulates gastric cancer development through targeting CXCL5.

BACKGROUND: Long noncoding RNAs (LncRNAs) have been reported to critically regulate gastric cancer (GC). Recently, it was reported that LBX2 antisense RNA 1 (LBX2-AS1) is abnormally expressed in GC. However, the role of LBX2-AS1 in the malignancy of GC is worth further discussion. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was used to determine the LBX2-AS1, miR-4766-5p and C-X-C motif chemokine (CXCL5) expression in GC tissues and cells. Dual-luciferase reporter assay was applied to examine the target relationship between LBX2-AS1 and miR-4766-5p or miR-4766-5p and CXCL5. Cell counting kit-8 (CCK-8) and Transwell assays were used to detect cell proliferation, migration and invasion rates. The protein expression of CXCL5 was confirmed using western blot. The RNA pull down experiment was used to verify the specificity of LBX2-AS1 and miR-4766-5p on BGC-823 and SGC-7901 cells. RESULTS: LBX2-AS1 was up-regulated in GC tissues and cells, and its knockdown suppressed proliferation, migration and invasion of GC cells. While, overexpression of LBX2-AS1 increased proliferation and increased CXCL5 mRNA level. CXCL5 improved cell proliferation, migration and invasion of GC cells. LBX2-AS1 could bind to miR-4766-5p to regulate CXCL5 expression. Overexpression of CXCL5 overturned those effects of miR-4766-5p in GC cells. RNA Pull down shown that BGC-823 and SGC-7901 cells, miR-4766-5p specifically binds to LBX2-AS1. CONCLUSIONS: In short, this study demonstrated that LBX2-AS1 promoted proliferation, migration and invasion through up-regulation CXCL5 mediated by miR-4766-5p in GC. The LBX2-AS1/miR-4766-5p/CXCL5 regulatory axis provides a theoretical basis for the research on lncRNA-directed therapeutics in GC.

CRISPR-GEMM Pooled Mutagenic Screening Identifies KMT2D as a Major Modulator of Immune Checkpoint Blockade.

Immune checkpoint blockade (ICB) has shown remarkable clinical efficacy in several cancer types. However, only a fraction of patients will respond to ICB. Here, we performed pooled mutagenic screening with CRISPR-mediated genetically engineered mouse models (CRISPR-GEMM) in ICB settings, and identified KMT2D as a major modulator of ICB response across multiple cancer types. KMT2D encodes a histone H3K4 methyltransferase and is among the most frequently mutated genes in patients with cancer. Kmt2d loss led to increased DNA damage and mutation burden, chromatin remodeling, intron retention, and activation of transposable elements. In addition, Kmt2d-mutant cells exhibited increased protein turnover and IFNγ-stimulated antigen presentation. In turn, Kmt2d-mutant tumors in both mouse and human were characterized by increased immune infiltration. These data demonstrate that Kmt2d deficiency sensitizes tumors to ICB by augmenting tumor immunogenicity, and also highlight the power of CRISPR-GEMMs for interrogating complex molecular landscapes in immunotherapeutic contexts that preserve the native tumor microenvironment. SIGNIFICANCE: ICB is ineffective in the majority of patients. Through direct in vivo CRISPR mutagenesis screening in GEMMs of cancer, we find Kmt2d deficiency sensitizes tumors to ICB. Considering the prevalence of KMT2D mutations, this finding potentially has broad implications for patient stratification and clinical decision-making.This article is highlighted in the In This Issue feature, p. 1775.

Functional modulation of CD8+ T cell by approved novel immune enhancer: Nocardia rubra Cell-Wall Skeletons (Nr-CWS).

Nocardia rubra cell wall skeleton (Nr-CWS) has been reported to have innate immunostimulating and anti-tumor activities. However, the immunomodulatory effects of Nr-CWS on CD8+ T cells and their related mechanisms are still unknown. In this work, our team purified CD8+T cells from spleen cells and explored the phenotype and function of NR-CWS in vitro on CD8+T cells. We observed that Nr-CWS can significantly up-regulate the expression of CD69 and CD25 on CD8+T cells, with no significant effect on apoptosis or cell death of CD8+T cells that occurs in vitro during culture. In addition, the effect of perforin and granzyme B was increased after Nr-CWS treatment, but did not substantially alter the expression of TRAIL and FasL. A variety of cytokine analyses have shown that of the cytokines examined (IFN-γ, TNF-α, IL-2, IL-4, IL-5, IL-6 and IL-10), only IFN-γ and TNF The increase in -α was more pronounced, and the effect of Nr-CWS in CD8+T cell culture medium on CD8+ T cells was independent of Th cells. Our results demonstrated that Nr-CWS could up-regulate CD69 and CD25 expression on CD8+T cells, promoting IFN-γ and TNF-α secretion, and enhancing perforin and granzyme B production. Thus Nr-CWS may have Immunoaugmenting therapeutic activity via an increase in CD8+T cells response.

RASAL1 induces to downregulate the SCD1, leading to suppression of cell proliferation in colon cancer via LXRα/SREBP1c pathway.

BACKGROUND: Recent studies have confirmed that RASAL1 has an antitumor effect in many cancers, but its functional role and the molecular mechanism underlying in colon cancer has not been investigated. RESULTS: We collected human colon cancer tissues and adjacent non-tumor tissues, human colon cancer cell lines LoVo, CaCo2, SW1116, SW480 and HCT-116, and normal colonic mucosa cell line NCM460. RT-qPCR was used to detect the RASAL1 level in the clinical tissues and cell lines. In LoVo and HCT-116, RASAL1 was artificially overexpressed. Cell viability and proliferation were measured using CCK-8 assays, and cell cycle was detected via PI staining and flow cytometry analysis. RASAL1 significantly inhibited the cell proliferation via inducing cell cycle arrest, suppressed cell cycle associated protein expression, and decreased the lipid content and inhibited the SCD1 expression. Moreover, SCD1 overexpression induced and downregulation repressed cell proliferation by causing cell cycle arrest. Additionally, luciferase reporter assays were performed to confirm the direct binding between SREBP1c, LXRα and SCD1 promoter, we also demonstrated that RASAL1 inhibit SCD1 3'-UTR activity. RASAL1 inhibited tumor growth in xenograft nude mice models and shows inhibitory effect of SCD1 expression in vivo. CONCLUSION: Taken together, we concluded that RASAL1 inhibited colon cancer cell proliferation via modulating SCD1 activity through LXRα/SREBP1c pathway.