Metabolic reprogramming, a pivotal hallmark of cancer, plays a crucial role in both the initiation and progression of colorectal cancer (CRC). Despite the vast unknowns surrounding the identity and biological activities of most natural metabolites in diseases, our study, utilizing native metabolomics results through GC-MS/MS, identified a small molecule, 4,4-Dimethyl-2-cyclohexen-1-one, named HEX-1 in the serum of CRC patients. We have further explored and assessed its biological activities. HEX-1 suppressed the proliferation of cancer cells and tumorigenesis via the inactivation and sensitization of PIN1. Notably, HEX-1 exhibits similar functional effects as all-trans retinoic acid (atRA) but stands out by not inducing the degradation of PIN1 mRNA or protein expression, unlike biological compounds associated with atRA. HEX-1 demonstrated the ability to induce G1/S arrest in vitro and ameliorate the progression of inflammatory CRC in mice by remodeling the gut microbiota. As volatile organic compounds (VOCs), HEX-1 could be detected feasibly. Its unique ability to penetrate whole cell populations positions it as a promising approach for cancer therapy and as an enhancer for chemotherapy and immunotherapy. The findings suggest that HEX-1 holds the potential as a valuable addition to the armamentarium against CRC.

Gastric cancer (GC) remains a primary contributor to cancer-associated deaths worldwide, especially in East Asia. We investigated the function of nuclear-localized full-length FOXP3 (FOXP3FL) as an oncosuppressive factor in GC. Total FOXP3 was markedly reduced in GC tissues versus adjacent normal mucosa, with distinct cytoplasmic and nuclear patterns. Functional assays revealed that nuclear overexpression of FOXP3FL suppresses proliferation, migration, and invasion of GC cells in vitro and in vivo and promotes cellular senescence in vivo. Mechanistically, FOXP3FL directly represses MYC transcription and induces CDKN1A, thereby restraining proliferation and metastasis. These transcriptional changes, together with concomitant PTEN upregulation and PI3K-P110α downregulation, collectively attenuate PI3K/AKT signaling and impair epithelial–mesenchymal transition (EMT) in FOXP3FL-expressing GC cells. The forkhead (FKH) domain is essential: its deletion yields cytoplasmic FOXP3ΔFKH, which loses transcriptional control and antitumor activity. Our findings underscore nuclear-localized FOXP3FL as a tumor suppressor whose FKH domain is integral to its suppressive function.

<p>PDF file - 752K, Table S1. ATF3 expression and clinicopathological findings in bladder cancer. Table S2. Relationship between ATF3 and GSN expression in bladder cancer. Table S3. Multivariate Cox proportional hazards regression for metastasis-free survival of patients with bladder cancer. Figure S1. Establishment and characterization of the highly metastatic cell subline T24-L. Figure S2. Agreement between pathologists and automated staining categories. Figure S3. ATF3 is downregulated in bladder cancer tissue. Figure S4. ATF3 regulates GSN expression in bladder cancer cells.</p>

T-cell-based immune checkpoint blockade therapy (ICB) can be undermined by local immunosuppressive M2-like tumor-associated macrophages (TAMs). However, modulating macrophages has proved difficult as the molecular and functional features of M2-TAMs on tumor growth are still uncertain. Here we reported that immunosuppressive M2 macrophages render cancer cells resistant to CD8+ T-cell-dependent tumor-killing refractory ICB efficacy by secreting exosomes. Proteomics and functional studies revealed that M2 macrophage-derived exosome (M2-exo) transmitted apolipoprotein E (ApoE) to cancer cells conferring ICB resistance by downregulated MHC-I expression curbing tumor intrinsic immunogenicity. Mechanistically, M2 exosomal ApoE diminished the tumor-intrinsic ATPase activity of binding immunoglobulin protein (BiP) to decrease tumor MHC-I expression. Sensitizing ICB efficacy can be achieved by the administration of ApoE ligand, EZ-482, enhancing ATPase activity of BiP to boost tumor-intrinsic immunogenicity. Therefore, ApoE may serve as a predictor and a potential therapeutic target for ICB resistance in M2-TAMs-enriched cancer patients. Collectively, our findings signify that the exosome-mediated transfer of functional ApoE from M2 macrophages to the tumor cells confers ICB resistance. Our findings also provide a preclinical rationale for treating M2-enriched tumors with ApoE ligand, EZ-482, to restore sensitivity to ICB immunotherapy.

Purpose Considerable evidence suggests that tumor cells with stemness features contribute to initiation, progression, recurrence of gastric cancer (GC) and resistance to therapy, but involvement of underlying regulators and mechanisms remain largely unclear. However, the clinical significance and biological function of Notum in GC tumor sphere formation and tumorigenesis remain unclear. Methods Bioinformatics analysis, RT-qPCR, western blot and imunohistochemistry staining were applied to characterize Notum expression in GC specimens. The early diagnostic value of Notum was analyzed by logistic regression analysis method. Cancer stemness assays were used in Notum knockdown and overexpressing cells in vitro and in vivo. RNA-seq was employed to reveal the downstream effectors of Notum. Results Notum is highly expressed in early stage of GC patients and stem-like GC cells. For discriminating the early-stage and advanced GC patients, the joint analysis had a better diagnostic value. Overexpression of Notum markedly increased stemness features of GC cells to promote tumor sphere formation and tumorigenesis. Conversely, Notum knockdown attenuated the stem-like cell properties in vitro and in vivo. Mechanically, Notum upregulates Sox2 through activating the PI3K/AKT signaling pathway. Notum inhibitor Caffeine exhibited a potent inhibitory effect on stemness features by impairing the PI3K/AKT signaling pathway activity and targeting Sox2. Conclusion Our findings confer a comprehensive and mechanistic function of Notum in GC tumor sphere formation and tumorigenesis that may provide a novel and promising target for early diagnosis and clinical therapy of GC.

LINC00355 is involved in the tumorigenesis of several types of cancer. We verified that LINC00355 is upregulated in gastric cancer (GC) and contributes to GC cells' proliferation and metastasis. RNA sequencing (RNA-seq) and rescue assays suggested that LINC00355 controls gastric carcinogenesis by regulating the expression of cell division cycle 42 (CDC42) guanosine triphosphatase (GTPases), thereby activating their downstream pathways. Most previous studies have shown that LINC00355 acts as a ceRNA by sponging miRNAs to modulate downstream gene expression. Our group focus on epigenetic regulatory potential of LINC00355 in gene expression. Mechanistically, LINC00355 binds to p300 histone acetyltransferase, specifying the histone modification pattern on the CDC42 promoter to activate CDC42 transcription, thereby altering GC cell biology. In addition, HNRNPA2B1, which is upregulated by LINC00355, recognizes the N6-methyladenosine (m6A) sites of CDC42 and enhances the stability of CDC42 mRNA transcripts. Therefore, LINC00355 is mechanistically, functionally, and clinically oncogenic in GC cells.

Immunotherapy targeting checkpoint blockade to rescue T cells from exhaustion has become an essential therapeutic strategy in treating cancers. Till now, little is known about the PD-L1 graphic pattern and characteristics in CD8(+) T cells. We combined cytometry by time-of-flight (CyTOF) and imaging mass cytometry (IMC) approaches to analyze CD8(+) T cells from primary lung cancers and discovered that PD-L1(+)CD8(+) T cells were enriched in tumor lesions, spatially localized with PD-1+CD8(+) T cells. Furthermore, PD-L1(+)CD8(+) T cells exerted regulatory functions that inhibited CD8(+) T cells proliferation and cytotoxic abilities through the PD-L1/PD-1 axis. Moreover, tumor-derived IL-27 promotes PD-L1(+)CD8(+) T cells development through STAT1/STAT3 signaling. Single-cell RNA sequencing data analysis further clarified PD-L1(+)CD8(+) T cells elevated in the components related to downregulation of adaptive immune response. Collectively, our data demonstrated that PD-L1(+)CD8(+) T cells enriched in lung cancer engaged in tolerogenic effects and may become a therapeutic target in lung cancer.

Protein arginine methyltransferase 5 (PRMT5) participates in the symmetric dimethylation of arginine residues of proteins and contributes to a wide range of biological processes. However, how PRMT5 affects the transcriptional and epigenetic programs involved in the establishment and maintenance of T cell subset differentiation and roles in antitumor immunity is still incompletely understood. In this study, using single-cell RNA and chromatin immunoprecipitation sequencing, we found that mouse T cell-specific deletion of PRMT5 had greater effects on CD8(+) than CD4(+) T cell development, enforcing CD8(+) T cell differentiation into Klrg1(+) terminal effector cells. Mechanistically, T cell deficiency of PRMT5 activated Prdm1 by decreasing H4R3me2s and H3R8me2s deposition on its loci, which promoted the differentiation of Klrg1(+)CD8(+) T cells. Furthermore, effector CD8(+) T cells that transited to memory precursor cells were decreased in PRMT5-deficient T cells, thus causing dramatic CD8(+) T cell death. In addition, in a mouse lung cancer cell line-transplanted tumor mouse model, the percentage of CD8(+) T cells from T cell-specific deletion of PRMT5 mice was dramatically lost, but CD8(+)Foxp3(+) and CD8(+)PDL1(+) regulatory T cells were increased compared with the control group, thus accelerating tumor progression. We further verified these results in a mouse colon cancer cell line-transplanted tumor mouse model. Our study validated the importance of targeting PRMT5 in tumor treatment, because PRMT5 deficiency enforced Klrg1(+) terminal CD8(+) T cell development and eliminated antitumor activity.

ATF3 has been reported to be dysregulated in various cancers and involved in various steps of tumorigenesis. However, the mechanisms underlying the abnormal expression of ATF3 and its biological function in gastric cancer (GC) have not been well investigated. Here, we report ATF3 as one of the key regulators of GC development and progression. Patients with low ATF3 expression had shorter survival and a poorer prognosis. In vitro and in vivo assays investigating ATF3 alterations revealed a complex integrated phenotype that affects cell growth and migration. Strikingly, high-throughput sequencing and microarray analysis of cells with ATF3 silencing or of ATF3-low GC tissues indicated alterations in the Wnt signaling pathway, focal adhesions and adherens junctions. Mechanistically, the expression of β-catenin and cell migration inducing hyaluronidase 1 (CEMIP) was significantly upregulated in GC cells with downregulated ATF3, which was synergistically repressed by the β-catenin/TCF3 signaling axis and noncoding RNA miR-17-5p and HOXA11-AS. In addition, we found that WDR5 expression was promoted by TCF3 and is involved in miR-17-5p and HOXA11-AS activation in GC cells. Taken together, our findings revealed the mechanism of ATF3 downregulation and its biological role in regulating the expression of Wnt signaling-related genes during GC progression, suggesting new informative biomarkers of malignancy and therapeutic directions for GC patients.

Angiogenesis is closely associated with tumorigenesis, invasion, and metastasis by providing oxygen and nutrients. Recently, increasing evidence indicates that cancer-derived exosomes which contain proteins, coding, and noncoding RNAs (ncRNAs) were shown to have proangiogenic function in cancer. A 26-nt-long ncRNA (X26nt) is generated in the process of inositol-requiring enzyme 1 alpha (IRE1α)-induced unspliced XBP1 splicing. However, the role of X26nt in the angiogenesis of gastric cancer (GC) remains largely unknown. In the present study, we found that X26nt was significantly elevated in GC and GC exosomes. Then, we verified that X26nt could be delivered into human umbilical vein endothelial cells (HUVECs) via GC cell exosomes and promote the proliferation, migration, and tube formation of HUVECs. We revealed that exosomal X26nt decreased vascular endothelial cadherin (VE-cadherin) by directly combining the 3'UTR of VE-cadherin mRNA in HUVECs, thereby increasing vascular permeability. We further demonstrated that X26nt accelerates the tumor growth and angiogenesis in a mouse subcutaneous tumor model. Our findings investigate a unique intercellular communication mediated by cancer-derived exosomes and reveal a novel mechanism of exosomal X26nt in the regulation of tumor vasculature.

Although CD4(+)CD45RA(-)Foxp3(l)degrees cytokine-secreting T cells (Fr.III cells) have been reported to be increased in systemic lupus erythematosus (SLE), their function and effects on response of B cells are still unclear. Here, we dissect how BACH2 regulates Fr.III cells function and promotes B-cell response in active SLE patients. We measured cytokines and BACH2 expression, and found that Fr.III cells from SLE patients produce much more inflammatory cytokines and were more able to promote B- cell proliferation, IgG, IgA, and TNF-alpha production than controls in a co-culture system. Fr.III cells expressed high levels of ICOS and CD154, but a low level of Tfr and BACH2, BACH2 expression was negatively correlated with SLE Disease Activity Index. Overexpressed of BACH2 in Fr.III cells, decreased cytokines expression and reduced B-cell response. Furthermore, we identified a reduction of H3K27ac level binding at the BACH2 locus in the SLE Fr.III cells and SLE serum stimulation decreased H3K27ac binding at the BACH2 locus, which could be restored using trichostatin A (TSA). In conclusion, BACH2 was associated with SLE disease activity, regulated the function of Fr.III cells, and promoted B-cells response. Targeting BACH2 may be a new immune intervention therapy of SLE.

Heterotypic interactions between tumor cells and macrophages can enable tumor progression and hold potential for the development of therapeutic interventions. However, the communication between tumors and macrophages and its mechanism are poorly understood. Here, we find that tumor‐associated macrophages (TAM) from tumor‐bearing mice have high amounts of lipid as compared to macrophages from tumor‐free mice. TAM also present high lipid content in clinical human gastric cancer patients. Functionally, TAM with high lipid levels are characterized by polarized M2‐like profiling, and exhibit decreased phagocytic potency and upregulated programmed death ligand 1 (PD‐L1) expression, blocking anti–tumor T cell responses to support their immunosuppressive function. Mechanistically, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis identifies the specific PI3K pathway enriched within lipid‐laid TAM. Lipid accumulation in TAM is mainly caused by increased uptake of extracellular lipids from tumor cells, which leads to the upregulated expression of gamma isoform of phosphoinositide 3‐kinase (PI3K‐γ) polarizing TAM to M2‐like profiling. Correspondingly, a preclinical gastric cancer model is used to show pharmacological targeting of PI3K‐γ in high‐lipid TAM with a selective inhibitor, IPI549. IPI549 restores the functional activity of macrophages and substantially enhances the phagocytosis activity and promotes cytotoxic‐T‐cell‐mediated tumor regression. Collectively, this symbiotic tumor‐macrophage interplay provides a potential therapeutic target for gastric cancer patients through targeting PI3K‐γ in lipid‐laden TAM.

Increased expression of the kinesin family member 23 (KIF23) has been verified in gastric cancer (GC) and its upregulation contributes to cell proliferation. Even though, the role of KIF23 has not been fully elucidated in GC, and the mechanisms of KIF23 as an oncogene remain unknown. To further identify its potential role in GC, we analyzed gene expression data from GC patients in GEO and TCGA datasets. KIF23 was upregulated in GC, and increased expression of KIF23 correlated with poor prognosis. Importantly, KIF23 inhibition not only suppressed GC cell proliferation, tumorigenesis, but also migration and invasion, and arrested the cell cycle in the G2/M phase. Mechanistic investigations confirmed that KIF23 activated the Wnt/β-catenin signaling pathway by directly interacting with APC membrane recruitment 1 (Amer1). Furthermore, KIF23 exhibited competitive binding with Amer1 to block the association of Amer1 with adenomatous polyposis coli (APC), thus relocating Amer1 from the membrane and cytoplasm to the nucleus and attenuating the ability of Amer1 to negatively regulate Wnt/β-catenin signaling, resulting in activation of this signaling pathway. Collectively, our findings demonstrated that KIF23 promoted GC cell proliferation by directly interacting with Amer1 and activating the Wnt/β-catenin signaling pathway.

Cancer immunotherapy has revolutionized cancer treatment, and it relies heavily on the comprehensive understanding of the immune landscape of the tumor microenvironment (TME). Here, we obtain a detailed immune cell atlas of esophageal squamous cell carcinoma (ESCC) at single-cell resolution. Exhausted T and NK cells, regulatory T cells (Tregs), alternatively activated macrophages and tolerogenic dendritic cells are dominant in the TME. Transcriptional profiling coupled with T cell receptor (TCR) sequencing reveal lineage connections in T cell populations. CD8 T cells show continuous progression from pre-exhausted to exhausted T cells. While exhausted CD4, CD8 T and NK cells are major proliferative cell components in the TME, the crosstalk between macrophages and Tregs contributes to potential immunosuppression in the TME. Our results indicate several immunosuppressive mechanisms that may be simultaneously responsible for the failure of immuno-surveillance. Specific targeting of these immunosuppressive pathways may reactivate anti-tumor immune responses in ESCC.

Background Serum/plasma YKL-40 can be a useful index that is associated with tumor development. However, the prognostic value of serum/plasma YKL-40 in patients with solid tumors is still unclear. We aimed to utilize the existing literature to investigate the prognostic value of serum/plasma YKL-40 in solid tumors. Methods An extensive literature search for relevant studies was conducted with the Embase, Medline and Web of Science databases. The effect on survival was measured with the hazard ratio (HR). Then, pooled HRs and 95% confidence intervals (CIs) were calculated using the random and fixed-effects models according to the heterogeneity of the included studies. Results This meta-analysis was based on 41 publications and comprised a total of 7762 patients with solid tumors. The pooled HR showed that elevated serum/plasma YKL-40 was significantly associated with poor OS (HR, 1.44; 95% CI 1.33-1.56). We also found that elevated serum/plasma YKL-40 had significant prognostic effects on OS in various cancer subgroups such as gastrointestinal tumors (HR, 1.37; 95% CI 1.18-1.58), ovarian cancer (HR, 2.27; 95% CI 1.69-3.06), melanoma (HR, 1.77; 95% CI 1.18-2.67), lung cancer (HR, 1.73; 95% CI 1.35-2.23), urologic neoplasms (HR, 1.61; 95% CI 1.08-2.40) and glioblastoma (HR, 1.23; 95% CI 1.07-1.42); in contrast, the prognostic effect of serum/plasma YKL-40 was not statistically significant in breast cancer (HR, 1.07; 95% CI 0.98-1.17). Conclusions The available evidence supports the hypothesis that elevated serum/plasma YKL-40 is associated with poor survival in patients with solid tumors and that serum/plasma YKL-40 may serve as a novel prognostic biomarker.

Tumor-associated macrophages (TAMs) are a major component of the tumor microenvironment and have been shown to contribute to tumor aggressiveness. However, the detailed mechanisms underlying the pro-metastatic effect of TAMs on gastric cancer are not clearly defined. Here, we show that TAMs are enriched in gastric cancer. TAMs are characterized by M2-polarized phenotype and promote migration of gastric cancer cells in vitro and in vivo. Furthermore, we find that M2-derived exosomes determine the TAMs-mediated pro-migratory activity. Using mass spectrometry, we identify that apolipoprotein E (ApoE) is highly specific and effective protein in M2 macrophages-derived exosomes. Moreover, TAMs are uniquely immune cells population expressed ApoE in gastric cancer microenvironment. However, exosomes derived from M2 macrophages of Apoe(-/-)mice have no significant effect on the migration of gastric cancer cells in vitro and in vivo. Mechanistically, M2 macrophage-derived exosomes mediate an intercellular transfer of ApoE-activating PI3K-Akt signaling pathway in recipient gastric cancer cells to remodel the cytoskeleton-supporting migration. Collectively, our findings signify that the exosome-mediated transfer of functional ApoE protein from TAMs to the tumor cells promotes the migration of gastric cancer cells.

During the past decade, tremendous progress has been made in terms of speed, read length, and throughput, along with a sharp reduction in per-base cost.Together, these advances democratized next generation sequence (NGS) and paved the way for the development of a large number of novel NGS applications in clinical diagnostics, especially in the field of non-invasive prenatal detection, rare genetic disease and cancer companion diagnostics.As technology advances, long-read single molecule sequencing began to emerge.Single cell, long-reads, transcriptome, and low cost will be the NGS direction.Due to the special nature of clinical testing, the current NGS clinical application system,including genetic counseling, testing standards, quality control, supervision, database construction etc, does not match the national conditions well and still faces a few challenges, needs to be constantly improved through the routine clinical practice in the future.