STAM2 knockdown inhibits proliferation, migration, and invasion by affecting the JAK2/STAT3 signaling pathway in gastric cancer

Starvation-induced HBP metabolic reprogramming and STAM2 O-GlcNAcylation facilitate bladder cancer metastasis

Metabolic reprogramming and epigenetic alternations are implicated in tumor progression and metastasis, but the metabolic and epigenetic mechanisms underlying lymphatic and distant metastasis of bladder cancer (BCa) remain poorly understood. In this study, we provide the first evidence that glutamine-fructose-6-phosphate aminotransferase 1 (GFAT1), the crucial rate-limiting switch of the hexosamine biosynthesis pathway (HBP), is considerably upregulated in the nutrient-scarce microenvironment and causes a high O-GlcNAcylation of signal transducing adaptor molecule 2 (STAM2), further facilitating lymphatic and distant metastasis of BCa. Inhibition of GFAT1 and O-GlcNAcylation impairs STAM2-induced metastasis. Mechanistically, O-GlcNAcylation of STAM2 at serine 375 augments protein stability by inhibiting proteasome degradation and ubiquitination. In addition, STAM2 O-GlcNAcylation facilitates Janus kinase 2 (JAK2) and signal transducer and activator of transcription (STAT3) phosphorylation, thus activating the epithelial‒mesenchymal transition. In summary, these results reveal a novel metabolic and epigenetic link mediating tumor metastasis, and indicate that targeting GFAT1 and STAM2 O-GlcNAcylation may serve as a promising treatment strategy for BCa progression.

Insights into tumor-derived exosome inhibition in cancer therapy

Exosomes are critical mediators of cell-to-cell communication in physiological and pathological processes, due to their ability to deliver a variety of bioactive molecules. Tumor-derived exosomes (TDEs), in particular, carry carcinogenic molecules that contribute to tumor progression, metastasis, immune escape, and drug resistance. Thus, TDE inhibition has emerged as a promising strategy to combat cancer. In this review, we discuss the key mechanisms of TDE biogenesis and secretion, emphasizing their implications in tumorigenesis and cancer progression. Moreover, we provide an overview of small-molecule TDE inhibitors that target specific biogenesis and/or secretion pathways, highlighting their potential use in cancer treatment. Lastly, we present the existing obstacles and propose corresponding remedies for the future development of TDE inhibitors.

VPS25 Promotes an Immunosuppressive Microenvironment in Head and Neck Squamous Cell Carcinoma

The ESCRT (endosomal sorting complex required for transport) machinery is essential for various cellular processes, yet its role in head and neck squamous cell carcinoma (HNSCC) is poorly understood. We utilized The Cancer Genome Atlas (TCGA) datasets to analyze the expression of ESCRT genes. Bulk RNA-sequencing data and HNSCC tissue microarrays (TMAs) were used to evaluate VPS25 expression and its clinical significance. Single-cell RNA sequencing of tumor tissues and VPS25 knockdown experiments in CAL27 cells were used to investigate its biological functions. Immunohistochemistry, spatial transcriptomics, and immunotherapy datasets highlighted the involvement of VPS25 in immune suppression and its potential as a predictive biomarker. The results demonstrated significant VPS25 overexpression in HNSCC tissues, which correlated with poor clinical outcomes. It promoted tumor cell proliferation and migration while reducing immune cell infiltration in the tumor microenvironment (TME). Additionally, by upregulating PVR expression in tumor cells, VPS25 activated the immunosuppressive PVR-TIGIT signaling axis, thereby facilitating immune evasion. Furthermore, VPS25 emerged as a potential biomarker for predicting immunotherapy response. These findings highlight VPS25 as a pivotal regulator of tumor progression and immune evasion in HNSCC and a promising target for therapeutic strategies.

GRASLND regulates melanoma cell progression by targeting the miR-218-5p/STAM2 axis

BACKGROUND

Increasing evidence suggests that long noncoding RNAs (lncRNAs) play important regulatory roles in biological processes and are dysregulated in numerous tumors. The lncRNA GRASLND functions as an oncogene in many cancers, but its role in skin cutaneous melanoma (SKCM) requires further investigation.

METHODS

SiRNA transfection, wound - healing and transwell assays were performed to evaluate the effect of GRASLND on cellular function.

RESULTS

The present study demonstrated that GRASLND expression is increased in SKCM tissues and cell lines. The high expression of GRASLND was correlated with poor prognosis and immunotherapy outcomes. Knockdown of GRASLND significantly inhibited cell migration and invasion. In addition, we found that miR-218-5p directly binds to its binding site on GRASLND, and GRASLND and miR-218-5p demonstrate mutual inhibition. Furthermore, the miR-218-5p inhibitor partially eliminated the knockdown of GRASLND and inhibited its expression. We also demonstrated that GRASLND acts as a miR-218-5p sponge that positively regulates STAM2 expression in SKCM cells.

CONCLUSION

In summary, these data suggest that GRASLND functions by regulating miR-218-5p/STAM2 expression, suggesting an important role for the lncRNA‒miRNA-mRNA functional network and a new potential therapeutic target for SKCM.

STAM2 negatively regulates the MyD88-mediated NF-κB signaling pathway in miiuy croaker, Miichthys miiuy

Signal transducing adapter molecule 2 (STAM2), a member of the Signal Transducing Adapter Molecule (STAM) family, is a protein with significant implications in diverse signaling pathways and endocytic membrane trafficking. However, the role of the STAM2, especially in fish, remains largely unknown. In this study, we discovered that STAM2 negatively regulates the NF-κB signaling pathway, and its inhibitory effect is enhanced upon LPS induction. Our study confirmed that STAM2 can enhance the degradation of myeloid differentiation primary-response protein 88 (MyD88), an upstream regulator of NF-κB pathway. Furthermore, the UIM domain of STAM2 is important for the inhibition of MyD88. Mechanistically, STAM2 inhibits the NF-κB signaling pathway by targeting the MyD88 autophagy pathway. In addition, we showed that STAM2 promotes the proliferation of Vibrio harveyi. In summary, our study reveals that STAM2 inhibits NF-κB signaling activation and mediates innate immunity in teleost via the autophagy pathway.

Antagonizing roles of SHP1 in the pathogenesis of Helicobacter pylori infection

BACKGROUND

SHP1 has been documented as a tumor suppressor and it was thought to play an antagonistic role in the pathogenesis of Helicobacter pylori infection. In this study, the exact mechanism of this antagonistic action was studied.

MATERIALS AND METHODS

AGS, MGC803, and GES-1 cells were infected with H. pylori, intracellular distribution changes of SHP1 were first detected by immunofluorescence. SHP1 overexpression and knockdown were then constructed in these cells to investigate its antagonistic roles in H. pylori infection. Migration and invasion of infected cells were detected by transwell assay, secretion of IL-8 was examined via ELISA, the cells with hummingbird-like alteration were determined by microexamination, and activation of JAK2/STAT3, PI3K/Akt, and ERK pathways were detected by immunoblotting. Mice infection model was established and gastric pathological changes were evaluated. Finally, the SHP1 activator sorafenib was used to analyze the attenuating effect of SHP1 activation on H. pylori pathogenesis in vitro and in vivo.

RESULTS

The sub-localization of SHP1 changed after H. pylori infection, specifically that the majority of the cytoplasmic SHP1 was transferred to the cell membrane. SHP1 inhibited H. pylori-induced activation of JAK2/STAT3 pathway, PI3K/Akt pathway, nuclear translocation of NF-κB, and then reduced EMT, migration, invasion, and IL-8 secretion. In addition, SHP1 inhibited the formation of CagA-SHP2 complex by dephosphorylating phosphorylated CagA, reduced ERK phosphorylation and the formation of CagA-dependent hummingbird-like cells. In the mice infection model, gastric pathological changes were observed and increased IL-8 secretion, indicators of cell proliferation and EMT progression were also detected. By activating SHP1 with sorafenib, a significant curative effect against H. pylori infection was obtained in vitro and in vivo.

CONCLUSIONS

SHP1 plays an antagonistic role in H. pylori pathogenesis by inhibiting JAK2/STAT3 and PI3K/Akt pathways, NF-κB nuclear translocation, and CagA phosphorylation, thereby reducing cell EMT, migration, invasion, IL-8 secretion, and hummingbird-like changes.

PLCD3 inhibits apoptosis and promotes proliferation, invasion and migration in gastric cancer

Gastric cancer (GC) is a heterogeneous disease whose development is accompanied by alterations in a variety of pathogenic genes. The phospholipase C Delta 3 enzyme is a member of the phospholipase C family, which controls substance transport between cells in the body. However, its role in gastric cancer has not been discovered. The purpose of this study was to investigate the expression and mechanism of action of PLCD3 in connection to gastric cancer. By Western blot analysis and immunohistochemistry, PLCD3 mRNA and protein expression levels were measured, with high PLCD3 expression suggesting poor prognosis. In N87 and HGC-27 cells, the silencing of PLCD3 using small interfering RNA effectively induced apoptosis and inhibited tumor cell proliferation, invasion, and migration. Conversely, overexpression of PLCD3 using overexpressed plasmids inhibited apoptosis in AGS and BGC-823 cells and promoted proliferation, migration, and invasion. In order to investigate the underlying mechanisms, we conducted further analysis of PLCD3, which indicates that this protein is closely related to the cell cycle and EMT. Additionally, we found that overexpression of PLCD3 inhibits apoptosis and promotes the development of GC cells through JAK2/STAT3 signaling. In conclusion, PLCD3 inhibits apoptosis and promotes proliferation, invasion, and migration, which indicated that PLCD3 might serve as a therapeutic target for gastric cancer.

A novel functional peptide, named EQ-9 (ESETRILLQ), identified by virtual screening from regenerative cell secretome and its potential anti-aging and restoration effects in topical applications

Skin aging refers to a degenerative process that can be affected and regulated by intrinsic and extrinsic factors. The mesenchymal stem cell secretome covers a considerable number of regenerative molecules with anti-aging effects in a wide variety of circumstances. However, it is complex, time-consuming, and costly to identify specific compounds from thousands of natural molecules using conventional methods. With the development of computational biology and machine learning, an efficient workflow was generated to identify novel peptides with anti-aging and skin restoration potential. One of the candidate peptides was discovered and subsequently truncated to a novel peptide named EQ-9, with promising anti-aging effects for topical applications at a concentration of 10 ppm validated by experimental validation. The above-described paradigm is expected to be further applied to the virtual screening of novel peptide molecules targeting specific biological functions from a wide variety of natural resources.

The prognostic value of NLRP1/NLRP3 and its relationship with immune infiltration in human gastric cancer

BACKGROUND

Inflammasomes are related to tumorigenesis and immune-regulation. Here, we investigated the prognostic value of the NLR family pyrin domain containing (NLRP) 1/NLRP3 inflammasome and its potential mechanisms in immune-regulation in gastric cancer (GC).

METHODS

We analyzed the differential expression of NLRP1/NLRP3 between tumor and normal tissues using the Oncomine and Tumor Immune Estimate Resource (TIMER) databases. Immunohistochemistry and western blotting were used to detect NLRP1/NLRP3 protein expression in GC tissues. Correlations between NLRP1/NLRP3 expression levels and patient survival were analyzed using Kaplan-Meier survival curves. The relationships of NLRP1/NLRP3 expression and tumor-infiltrating immune cells/marker genes were assessed using the TIMER database. NLRP1/NLRP3 and immune checkpoint gene correlations were verified by single-gene co-expression analyses, and tumor immune-related pathways involving NLRP1/NLRP3 were analyzed using gene set enrichment analysis (GSEA).

RESULTS

Elevated NLRP1/NLRP3 expression was significantly correlated with lymph node metastasis, poor survival, immune-infiltrating cell abundances, and immune cell markers. NLRP3 showed stronger correlations with immune infiltration and the prognosis of gastric cancer. NLRP1 and NLRP3 might be involved in the same tumor immune-related pathways. Thus, high NLRP1/NLRP3 expression promotes immune cell infiltration and poor prognosis in GC. NLRP1/NLRP3, particularly NLRP3, may have important roles in immune infiltration and may serve as a prognostic biomarker for GC.

CONCLUSIONS

NLRP1/NLRP3, particularly NLRP3, may have important roles in immune infiltration and may serve as a prognostic biomarker for GC.

Comparative transcriptome and proteome reveal synergistic functions of differentially expressed genes and proteins implicated in an over-dominant silkworm heterosis of increased silk yield

We previously observed an over-dominant silkworm heterosis of increased yield in a cross of Bombyx mori nuclear polyhydrosis virus-resistant strain NB with a susceptible strain 306. In the present study, we found that heterosis also exists in crosses of NB with other susceptible strains, indicating it is a more general phenomenon. We performed comparative transcriptome and proteome and identified 1624 differentially expressed genes (DEGs) and 298 differentially expressed proteins (DEPs) in silk glands between parents and F1 hybrids, of which 24 DEGs/DEPs showed consistent expression at mRNA and protein levels revealed by Venn joint analysis. Their expressions are completely non-additive, mainly transgressive and under low-parent, suggesting recombination of parental genomes may be the major genetic mechanism for the heterosis. GO and KEGG analyses revealed that they may function in generally similar but distinctive aspects of metabolisms and processes with signal transduction and translation being most affected. Notably, they may not only up-regulate biosynthesis and transport of silk proteins but also down-regulate other unrelated processes, synergistically and globally remodelling the silk gland to increase yield and cause the heterosis. Our findings contribute insights into the understanding of silkworm heterosis and silk gland development and provide targets for transgenic manipulation to further increase the silk yield.

Targeted inhibition of tumor-derived exosomes as a novel therapeutic option for cancer

Mounting evidence indicates that tumor-derived exosomes (TDEs) play critical roles in tumor development and progression by regulating components in the tumor microenvironment (TME) in an autocrine or paracrine manner. Moreover, due to their delivery of critical molecules that react to chemotherapy and immunotherapy, TDEs also contribute to tumor drug resistance and impede the effective response of antitumor immunotherapy, thereby leading to poor clinical outcomes. There is a pressing need for the inhibition or removal of TDEs to facilitate the treatment and prognosis of cancer patients. Here, in the present review, we systematically overviewed the current strategies for TDE inhibition and clearance, providing novel insights for future tumor interventions in translational medicine. Moreover, existing challenges and potential prospects for TDE-targeted cancer therapy are also discussed to bridge the gaps between progress and promising applications.

Inhibiting or removing tumor-derived exosomes (TDEs), tiny membrane-bound packets of DNA, RNA, and proteins secreted by tumors, may improve cancer therapies. TDEs can suppress the body’s immune response, promote tumor progression and spread, and reduce efficacy of cancer drugs and immunotherapy. Gang Chen at Wuhan University, China, and co-workers have reviewed ways to remove or inhibit production of TDEs. They report that disruption of the genes for production of TDEs, drugs that inhibit TDE secretion, and removal of TDEs via plasma exchange or dialysis are all being investigated and show promise for reducing patient TDE load, thereby increasing the efficacy of anti-cancer drugs and immunotherapy. Future challenges include reducing side effects and finding less invasive ways to filter out TDEs. Gaining a better understanding of TDEs may help to improve therapies for many types of cancer.

Identification and Validation of an m6A Modification of JAK-STAT Signaling Pathway–Related Prognostic Prediction Model in Gastric Cancer

Background: Gastric cancer (GC) is one of the malignant tumors worldwide. Janus (JAK)–signal transduction and activator of transcription (STAT) signaling pathway is involved in cellular biological process and immune function. However, the association between them is still not systematically described. Therefore, in this study, we aimed to identify key genes involved in JAK-STAT signaling pathway and GC, as well as the potential mechanism.

Methods: The Cancer Genome Atlas (TCGA) database was the source of RNA-sequencing data of GC patients. Gene Expression Omnibus (GEO) database was used as the validation set. The predictive value of the JAK-STAT signaling pathway-related prognostic prediction model was examined using least absolute shrinkage and selection operator (LASSO); survival, univariate, and multivariate Cox regression analyses; and receiver operating characteristic curve (ROC) analyses to examine the predictive value of the model. Quantitative real-time polymerase chain reaction (qRT-PCR) and chi-square test were used to verify the expression of genes in the model and assess the association between the genes and clinicopathological parameters of GC patients, respectively. Then, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), gene set enrichment analysis, version 3.0 (GSEA), sequence-based RNA adenosine methylation site predictor (SRAMP) online websites, and RNA immunoprecipitation (RIP) experiments were used to predict the model-related potential pathways, m6A modifications, and the association between model genes and m6A.

Results: A four-gene prognostic model (GHR, PIM1, IFNA8, and IFNB1) was constructed, namely, riskScore. The Kaplan–Meier curves suggested that patients with high riskScore expression had a poorer prognosis than those with low riskScore expression (p = 0.006). Multivariate Cox regression analyses showed that the model could be an independent predictor (p < 0.001; HR = 3.342, 95%, CI = 1.834–6.088). The 5-year area under time-dependent ROC curve (AUC) reached 0.655. The training test set verified these results. Further analyses unveiled an enrichment of cancer-related pathways, m6A modifications, and the direct interaction between m6A and the four genes.

Conclusion: This four-gene prognostic model could be applied to predict the prognosis of GC patients and might be a promising therapeutic target in GC.

LncRNA MNX1-AS1: A novel oncogenic propellant in cancers

To date, recent studies have shown that long non-coding RNAs (lncRNAs) are key players in gene regulation processes involved in cancer pathogenesis. In general, Motor neuron and pancreas homeobox 1-antisense RNA1 (MNX1-AS1) is highly expressed in all cancers as reported so far and exerts oncogenic effects through different mechanisms. In this review, we comprehensively summarize the detailed mechanisms of potential functions of MNX1-AS1 in different cancer types as well as the latest knowledge highlighting the potential of MNX1-AS1 as a therapeutic target for cancer. Aberrant expression of MNX1-AS1 closely correlates with clinicopathological parameters. such as lymphatic metastasis, tumor size, tumor stage, OS and DFS. Thus, MNX1-AS1 can be used as a diagnostic and prognostic biomarker or even a therapeutic prognostic target. This article reviews its function, molecular mechanism and clinical prognosis in various malignancies.

Identification and Molecular Analysis of m6A-circRNAs from Cashmere Goat Reveal Their Integrated Regulatory Network and Putative Functions in Secondary Hair Follicle during Anagen Stage

Simple Summary

Cashmere is a natural, high-end textile material. It is derived from the secondary hair follicle (SHFs) tissue in the skin of cashmere goats. Previous studies have indicated that m⁶A modifications in circRNA molecules play important roles in a variety of cells through multiple mechanisms. However, little information is available on the expression profile and functional regulatory characteristics of m⁶A-modified circRNA (m⁶A-circRNA) in SHFs of cashmere goats. In this study, a total of 15 m⁶A-circRNAs were identified. Six of these m⁶A-circRNAs were revealed to have significantly higher expression in skin at anagen than at telogen. To gain insight into the potential regulatory mechanisms of the anagen up-regulated m⁶A-circRNAs, we constructed the regulatory networks along with related pathways in SHFs of cashmere goats. In addition, we found that the expression trends of four m⁶A-circRNAs in the SHFs during SHF cycles were highly similar to their host genes. However, the expression patterns of two m⁶A-circRNAs were inconsistent with the linear RNAs from their host genes in the SHFs of cashmere goats. These results will provide new insights to elucidate the biological functions and regulatory features of m⁶A-circRNA in SHF development and cashmere growth in goats.

Abstract

N⁶-methyladenosine (m⁶A) is the most abundant modification in linear RNA molecules. Over the last few years, interestingly, many circRNA molecules are also found to have extensive m⁶A modification sites with temporal and spatial specific expression patterns. To date, however, little information is available concerning the expression profiling and functional regulatory characteristics of m⁶A modified circRNAs (m⁶A-circRNAs) in secondary hair follicles (SHFs) of cashmere goats. In this study, a total of fifteen m⁶A-circRNAs were identified and characterized in the skin tissue of cashmere goats. Of these, six m⁶A-circRNAs were revealed to have significantly higher expression in skin at anagen compared with those at telogen. The constructed ceRNA network indicated a complicated regulatory relationship of the six anagen up-regulated m⁶A-circRNAs through miRNA mediated pathways. Several signaling pathways implicated in the physiological processes of hair follicles were enriched based on the potential regulatory genes of the six anagen up-regulated m⁶A-circRNAs, such as TGF-beta, axon guidance, ribosome, and stem cell pluripotency regulatory pathways, suggesting the analyzed m⁶A-circRNAs might be essentially involved in SHF development and cashmere growth in cashmere goats. Further, we showed that four m⁶A-circRNAs had highly similar expression trends to their host genes in SHFs of cashmere goats including m⁶A-circRNA-ZNF638, -TULP4, -DNAJB6, and -CAT. However, the expression patterns of two m⁶A-circRNAs (m⁶A-circRNA-STAM2 and -CAAP1) were inconsistent with the linear RNAs from their host genes in the SHFs of cashmere goats. These results provide novel information for eluci-dating the biological function and regulatory characteristics of the m⁶A-circRNAs in SHF development and cashmere growth in goats.

COL6A6 inhibits the proliferation and metastasis of non-small cell lung cancer through the JAK signalling pathway

Background

Collagen type VI alpha 6 chain (COL6A6) plays a vital role in maintaining cell structural integrity and regulating cell function. It has been proven to be a tumor suppressor gene and molecular therapeutic target. However, the mechanism of COL6A6 in non-small cell lung cancer (NSCLC) has not been elucidated. The purpose of this study was to investigate the relationship between COL6A6 and NSCLC.

Methods

We analyzed the expression of COL6A6 in NSCLC using public databases and verified the findings in NSCLC tissues and cells. The protein expression of COL6A6 was evaluated by Western blot. The CCK8 and Transwell assays were used to assess the invasion ability of NSCLC cells after COL6A6 knockdown. At the same time, we discussed the role of the JAK signalling pathway that may be related to COL6A6.

Results

Bioinformatics analysis showed that COL6A6 expression was downregulated in NSCLC, and its high expression was associated with a better prognosis of NSCLC. In vitro, the expression of COL6A6 in NSCLC tissues was significantly lower than that in adjacent tissues. Furthermore, COL6A6 knockout accelerated the proliferation, invasion, and migration of NSCLC cells and activated the JAK signalling pathway.

Conclusions

Our study illustrates that COL6A6 is a tumor suppressor gene in NSCLC and is involved in NSCLC tumorigenesis by regulating the JAK signalling pathway. Therefore, COL6A6 holds promise as a molecular therapeutic target for NSCLC.