PLD1 promotes tumor invasion by regulation of MMP-13 expression via NF-κB signaling in bladder cancer

MyD88 Signaling Accompanied by Microbiota Changes Supports Urinary Bladder Carcinogenesis

Urinary bladder cancer (BC) inflicts a significant impairment of life quality and poses a high mortality risk. Schistosoma haematobium infection can cause BC, and the urinary microbiota of BC patients differs from healthy controls. Importantly, intravesical instillation of the bacterium Bacillus Calmette-Guerin stands as the foremost therapy for non-muscle invasive BC. Hence, studying the receptors and signaling molecules orchestrating bacterial recognition and the cellular response in the context of BC is of paramount importance. Thus, we challenged Toll-like receptor 4 (Tlr4) and myeloid differentiation factor 88 (Myd88) knock-out (KO) mice with N-butyl-N-(4-hydroxylbutyl)-nitrosamine (BBN), a well-known urinary bladder carcinogen. Gut microbiota, gene expression, and urinary bladder pathology were followed. Acute exposure to BBN did not reveal a difference in bladder pathology despite differences in the animal's ability to recognize and react to bacteria. However, chronic treatment resulted in reduced cancer invasiveness among Myd88KO mice while the absence of functional Tlr4 did not influence BC development or progression. These differences correlate with a heightened abundance of the Faecalibaculum genus and the lowest microbial diversity observed among Myd88KO mice. The presented data underscore the important role of microbiota composition and MyD88-mediated signaling during bladder carcinogenesis.

A positive feedback loop between PLD1 and NF-κB signaling promotes tumorigenesis of nasopharyngeal carcinoma

Phospholipase D (PLD) lipid-signaling enzyme superfamily has been widely implicated in various human malignancies, but its role and underlying mechanism remain unclear in nasopharyngeal carcinoma (NPC). Here, we analyze the expressions of 6 PLD family members between 87 NPC and 10 control samples through transcriptome analysis. Our findings reveal a notable upregulation of PLD1 in both NPC tumors and cell lines, correlating with worse disease-free and overall survival in NPC patients. Functional assays further elucidate PLD1's oncogenic role, demonstrating its pivotal promotion of critical tumorigenic processes such as cell proliferation and migration in vitro, as well as tumor growth in vivo. Notably, our study uncovers a positive feedback loop between PLD1 and the NF-κB signaling pathway to render NPC progression. Specifically, PLD1 enhances NF-κB activity by facilitating the phosphorylation and nuclear translocation of RELA (p65), which in turn binds to the promoter of PLD1, augmenting its expression. Moreover, RELA overexpression markedly rescues the inhibitory effects in PLD1-depleted NPC cells. Importantly, the application of the PLD1 inhibitor, VU0155069, substantially inhibits NPC tumorigenesis in a patient-derived xenograft (PDX) model. Together, our findings identify PLD1/NF-κB signaling as a positive feedback loop with promising therapeutic and prognostic potential in NPC.

Matrix metalloproteinases in chronic rhinosinusitis

INTRODUCTION

Matrix metalloproteinases (MMPs) are a group of enzymes that are essential in maintaining extracellular matrix (ECM) homeostasis, regulating inflammation and tissue remodeling. In chronic rhinosinusitis (CRS), the overexpression of certain MMPs can contribute to chronic nasal tissue inflammation, ECM remodeling, and tissue repair.

AREAS COVERED

This review provides a comprehensive overview of the biological characteristics and functions of the MMP family, particularly focusing on the expression and activity of MMPs in patients with CRS, and delves into their role in the pathogenesis of CRS and their potential as therapeutic targets.

EXPERT OPINION

MMPs are important in tissue remodeling and have been implicated in the pathophysiology of CRS. Previous studies have shown that the expression of MMPs is upregulated in the nasal mucosa of patients with CRS and positively correlates with the severity of CRS. However, there is still a large gap in the research content of MMP in CRS, and the specific expression and pathogenic mechanism of MMP still need to be clarified. The significance and value of the ratio of MMP to tissue inhibitors of metalloproteinase (TIMP) in diseases still need to be demonstrated. Moreover, further studies are needed to assess the efficacy and safety of biologics that target MMPs in patients with CRS.

Lactate/GPR81 recruits regulatory T cells by modulating CX3CL1 to promote immune resistance in a highly glycolytic gastric cancer

Lactate plays an important role in shaping immune tolerance in tumor microenvironment (TME) and correlates with poor prognosis in various solid tumors. Overcoming the immune resistance in an acidic TME may improve the anti-tumor immunity. Here, this study elucidated that via G-protein-coupled receptor 81 (GPR81), lactate could modulate immune tolerance in TME by recruiting regulatory T cells (Tregs) in vitro and in vivo. A high concentration of lactate was detected in cell supernatant and tissues of gastric cancer (GC), which was modulated by lactic dehydrogenase A (LDHA). GPR81 was the natural receptor of lactate and was overexpressed in different GC cell lines and samples, which correlated with poor outcomes in GC patients. Lactate/GPR81 signaling could promote the infiltration of Tregs into TME by inducing the expression of chemokine CX3CL1. GPR81 deficiency could decrease the infiltration of Tregs into TME, thereby inhibiting GC progression by weakening the inhibition of CD8+T cell function in a humanized mouse model. In conclusion, targeting the lactate/GPR81 signaling may potentially serve as a critical process to overcome immune resistance in highly glycolytic GC.

Raf/MEK/ERK Signaling Pathway Is Involved in the Inhibition of Glioma Cell Proliferation and Invasion in the Ketogenic Microenvironment

OBJECTIVE

A high-fat, low-carbohydrate ketogenic diet has been used to treat malignant glioma, in which the Raf/MEK/ERK signaling pathway is overactivated. However, whether the Raf/MEK/ERK signaling pathway is involved in the therapeutic effect of ketone bodies remains unknown. In this study, we investigated the effects of a major ketone body, 3-hydroxybutyric acid (3-HBA), on the proliferation and metastasis of malignant glioblastoma cells and the underlying mechanism.

METHODS

Two human malignant glioblastoma cell lines (U87 and U251) were treated with different concentrations of 3-HBA with or without the Raf inhibitor PAF C-16 for 24 h. Cell proliferation, cell cycle, cell invasion, and phospholipase D1 (PLD1) activity were determined. Protein and gene expression levels of Raf/MEK/ERK signaling pathway members were examined.

RESULTS

3-HBA significantly decreased cell proliferation, invasion, and intracellular PLD1 activity in both U87 and U251 glioblastoma cell lines. 3-HBA treatment significantly increased the proportion of cells in the G1 phase and decreased the proportion of cells in S phase in U87 cells. In the U251 line, the proportion of treated cells in S phase was increased and proportion of cells in G2 was decreased. 3-HBA treatment also significantly decreased the protein expression levels of Raf, MEK, p-MEK, ERK, p-ERK, and PLD1 while increasing p53 expression; an effect that was similar to treatment with the Raf inhibitor. Co-treatment of 3-HBA with the Raf inhibitor further enhanced the effects of the 3-HBA in both cell lines.

CONCLUSION

We confirmed that a ketogenic microenvironment can inhibit glioma cell proliferation and invasion by downregulating the expression of PLD1 through the Raf/MEK/ERK signaling pathway.

The Preventive Effect of Specific Collagen Peptides against Dexamethasone-Induced Muscle Atrophy in Mice

Muscle atrophy, also known as muscle wasting, is the thinning of muscle mass due to muscle disuse, aging, or diseases such as cancer or neurological problems. Muscle atrophy is closely related to the quality of life and has high morbidity and mortality. However, therapeutic options for muscle atrophy are limited, so studies to develop therapeutic agents for muscle loss are always required. For this study, we investigated how orally administered specific collagen peptides (CP) affect muscle atrophy and elucidated its molecular mechanism using an in vivo model. We treated mice with dexamethasone (DEX) to induce a muscular atrophy phenotype and then administered CP (0.25 and 0.5 g/kg) for four weeks. In a microcomputed tomography analysis, CP (0.5 g/kg) intake significantly increased the volume of calf muscles in mice with DEX-induced muscle atrophy. In addition, the administration of CP (0.25 and 0.5 g/kg) restored the weight of the gluteus maximus and the fiber cross-sectional area (CSA) of the pectoralis major and calf muscles, which were reduced by DEX. CP significantly inhibited the mRNA expression of myostatin and the phosphorylation of Smad2, but it did not affect TGF-β, BDNF, or FNDC5 gene expression. In addition, AKT/mTOR, a central pathway for muscle protein synthesis and related to myostatin signaling, was enhanced in the groups that were administered CP. Finally, CP decreased serum albumin levels and increased TNF-α gene expression. Collectively, our in vivo results demonstrate that CP can alleviate muscle wasting through a multitude of mechanisms. Therefore, we propose CP as a supplement or treatment to prevent muscle atrophy.

Peptide-drug conjugates (PDCs): a novel trend of research and development on targeted therapy, hype or hope?

Peptide-drug conjugates (PDCs) are the next generation of targeted therapeutics drug after antibody-drug conjugates (ADCs), with the core benefits of enhanced cellular permeability and improved drug selectivity. Two drugs are now approved for market by US Food and Drug Administration (FDA), and in the last two years, the pharmaceutical companies have been developing PDCs as targeted therapeutic candidates for cancer, coronavirus disease 2019 (COVID-19), metabolic diseases, and so on. The therapeutic benefits of PDCs are significant, but poor stability, low bioactivity, long research and development time, and slow clinical development process as therapeutic agents of PDC, how can we design PDCs more effectively and what is the future direction of PDCs? This review summarises the components and functions of PDCs for therapeutic, from drug target screening and PDC design improvement strategies to clinical applications to improve the permeability, targeting, and stability of the various components of PDCs. This holds great promise for the future of PDCs, such as bicyclic peptide‒toxin coupling or supramolecular nanostructures for peptide-conjugated drugs. The mode of drug delivery is determined according to the PDC design and current clinical trials are summarised. The way is shown for future PDC development.

Glucocorticoids coordinate the bladder peripheral clock and diurnal micturition pattern in mice

Peripheral clocks function to regulate each organ and are synchronized though various molecular and behavioral signals. However, signals that entrain the bladder clock remain elusive. Here, we show that glucocorticoids are a key cue for the bladder clock in vitro and in vivo. A pBmal1-dLuc human urothelial cell-line showed significant shifts in gene expression after cortisol treatment. In vivo, rhythmic bladder clock gene expression was unchanged by bilateral adrenalectomy but shifted 4 h forward by corticosterone administration at the inactive phase. Moreover, the bladder clock shifted 8-12 h in mice that underwent both bilateral adrenalectomy and corticosterone administration at the inactive phase. These mice showed decreases in the diurnal rhythm of volume voided per micturition, while maintaining diurnal activity rhythms. These results indicate that the diurnal rhythm of glucocorticoid signaling is a zeitgeber that overcomes other bladder clock entrainment factors and coordinates the diurnal rhythm of volume voided per micturition.

Multi-omics profiling of PC-3 cells reveals bufadienolides-induced lipid metabolic remodeling by regulating long-chain lipids synthesis and hydrolysis

INTRODUCTION

Lipid metabolism participates in various biological processes such as proliferation, apoptosis, migration, invasion, and maintenance of membrane homeostasis of prostate tumor cells. Bufadienolides, the active ingredients of Chansu, show a robust anti-proliferative effect against prostate cancer cells in vitro, but whether bufadienolides could regulate the lipid metabolism in prostate cancer has not been evaluated.

OBJECTIVES

Our study explored the regulatory effects of bufadienolides on lipid metabolism in human prostate carcinoma cells (PC-3).

METHODS

Untargeted lipidomics and transcriptomics were combined to study the effect of different bufadienolides interventions on lipid and gene changes of PC-3 cells. The key genes related to lipid metabolism and prostate cancer development were verified by qPCR and western blotting.

RESULTS

Lipidomic analysis showed that the active bufadienolides significantly downregulated the content of long-chain lipids of PC-3 cells. Based on transcriptomic and qPCR analyses, many genes related to lipid metabolism were significantly regulated by active bufadienolides, such as ELOVL6, CYP2E1, GAL3ST1, CERS1, PLA2G10, PLD1, SPTLC3, and GPX2. Bioinformatics analysis of the Cancer Genome Atlas database and literature retrieval showed that elongation of very long-chain fatty acids protein 6 (ELOVL6) and phospholipase D1 (PLD1) might be important regulatory genes. Western blot analysis revealed that active bufadienolides could downregulate PLD1 protein levels which might promote anti-prostate cancer effect.

CONCLUSIONS

All these findings support that bufadienolides might induce lipid metabolic remodeling by regulating long-chain lipids synthesis and phospholipid hydrolysis to achieve an anti-prostate cancer effect, and PLD1 would probably be the key protein.

Chloroform Fraction of Prasiola japonica Ethanolic Extract Alleviates UPM 1648a-Induced Lung Injury by Suppressing NF-κB Signaling

Prasiola japonica is an edible alga, and the ethanol extract of P. japonica (Pj-EE) possesses various biological activities. Interestingly, in a recent study, we observed the potent anti-inflammatory activity of the chloroform fraction of Pj-EE (Pj-EE-CF). Thus, to extend the application of Pj-EE-CF, we further studied its effects on lung injury. To establish an experimental model of lung injury, we nasally administered urban particulate matter UPM 1648a (50 mg/kg) to mice. In addition, BEAS-2B cells were treated with 300 μg/mL of UPM 1648a for in vitro analysis. Intranasal administration of UPM 1648a increased lung injury score, macrophage infiltration, and upregulation of the inflammatory enzyme inducible nitric oxide synthase (iNOS) in lung tissues. On the other hand, oral administration of Pj-EE-CF (25, 50, and 100 mg/kg) alleviated these pathological features as assessed by lung wet/dry ratio, lung injury score, bronchoalveolar lavage fluid (BALF) protein amount in the lung tissues up to 70%, 95%, and 99%, respectively. In addition, Pj-EE-CF down-regulated the release of inflammatory cytokines, interleukins (ILs), tumor necrosis factor (TNF)-α, and interferon (IFN)-γ elevated by UPM 1648a in the lung tissues and lung BALF up to 95%. According to Western blot and luciferase assay, Pj-EE-CF (100 mg/kg in vivo or 50 and 100 μg/mL in vitro) significantly reduced the nuclear factor-κB (NF-κB) signal activated by UPM 1648a. Finally, UPM 1648a increased cellular reactive oxygen species (ROS) levels in BEAS-2B cells, while Pj-EE-CF reduced them. These results suggest that Pj-EE-CF alleviates UPM 1648a-induced lung damage via anti-inflammatory and antioxidant activities and by suppressing NF-κB signaling. In conclusion, these observations imply that Pj-EE-CF could be a practical component of food supplements to mitigate air pollution-derived lung damage.

Guettarda crispiflora Vahl Methanol Extract Ameliorates Acute Lung Injury and Gastritis by Suppressing Src Phosphorylation

Many species in the genus Guettarda are known to exert anti-inflammatory effects and are used as traditional medicinal plants to treat various inflammatory symptoms. However, no studies on the inflammatory activities of Guettarda crispiflora Vahl have been reported. The aim of the study was to investigate in vitro and in vivo the anti-inflammatory effects of a methanol extract of Guettarda crispiflora Vahl (Gc-ME). To determine the anti-inflammatory activity of Gc-ME, lipopolysaccharide (LPS)-, poly(I:C)-, or Pam3CSK4-treated RAW264.7 cells, HCl/EtOH- and LPS-treated mice were employed for in vitro and in vivo tests. LPS-induced nitric oxide production in RAW264.7 cells was determined by Griess assays and cytokine gene expression in LPS-activated RAW264.7 cells, confirmed by RT- and real-time PCR. Transcriptional activation was evaluated by luciferase reporter gene assay. Target protein validation was assessed by Western blot analysis and cellular thermal shift assays (CETSA) with LPS-treated RAW264.7 and gene-transfected HEK293 cells. Using both a HCl/EtOH-induced gastritis model and an LPS-induced lung injury model, inflammatory states were checked by scoring or evaluating gastric lesions, lung edema, and lung histology. Phytochemical fingerprinting of Gc-ME was observed by using liquid chromatography-mass spectrometry. Nitric oxide production induced by LPS and Pam3CSK4 in RAW264.7 cells was revealed to be reduced by Gc-ME. The LPS-induced upregulation of iNOS, COX-2, IL-6, and IL-1β was also suppressed by Gc-ME treatment. Gc-ME downregulated the promotor activities of AP-1 and NF-κB triggered by MyD88- and TRIF induction. Upstream signaling proteins for NF-κB activation, namely, p-p50, p-p65, p-IκBα, and p-Src were all downregulated by Ch-EE. Moreover, Src was revealed to be directly targeted by Gc-ME. This extract, orally treated strongly, attenuated the inflammatory symptoms in HCl/EtOH-treated stomachs and LPS-treated lungs. Therefore, these results strongly imply that Guettarda crispiflora can be developed as a promising anti-inflammatory remedy with Src-suppressive properties.

Antioxidant, Anti-Inflammatory, Anti-Menopausal, and Anti-Cancer Effects of Lignans and Their Metabolites

Since chronic inflammation can be seen in severe, long-lasting diseases such as cancer, there is a high demand for effective methods to modulate inflammatory responses. Among many therapeutic candidates, lignans, absorbed from various plant sources, represent a type of phytoestrogen classified into secoisolariciresionol (Seco), pinoresinol (Pino), matairesinol (Mat), medioresinol (Med), sesamin (Ses), syringaresinol (Syr), and lariciresinol (Lari). Lignans consumed by humans can be further modified into END or ENL by the activities of gut microbiota. Lignans are known to exert antioxidant and anti-inflammatory activities, together with activity in estrogen receptor-dependent pathways. Lignans may have therapeutic potential for postmenopausal symptoms, including cardiovascular disease, osteoporosis, and psychological disorders. Moreover, the antitumor efficacy of lignans has been demonstrated in various cancer cell lines, including hormone-dependent breast cancer and prostate cancer, as well as colorectal cancer. Interestingly, the molecular mechanisms of lignans in these diseases involve the inhibition of inflammatory signals, including the nuclear factor (NF)-κB pathway. Therefore, we summarize the recent in vitro and in vivo studies evaluating the biological effects of various lignans, focusing on their values as effective anti-inflammatory agents.

Exploration and validation of metastasis-associated genes for skin cutaneous melanoma

Skin cutaneous melanoma is a malignant and highly metastatic skin tumor, and its morbidity and mortality are still rising worldwide. However, the molecular mechanisms that promote melanoma metastasis are unclear. Two datasets (GSE15605 and GSE46517) were retrieved to identify the differentially expressed genes (DEGs), including 23 normal skin tissues (N), 77 primary melanoma tissues (T) and 85 metastatic melanoma tissues (M). Gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis were performed to explore the functions of the DEGs. We constructed protein–protein interaction network using the STRING database and Cytoscape software. Using the cytoHubba plugin of Cytoscape, we identified the most significant hub genes by five analytical methods (Degree, Bottleneck, MCC, MNC, and EPC). Hub gene expression was validated using the UALCAN website. Clinical relevance was investigated using The Cancer Genome Atlas resources. Finally, we explored the association between metastasis-associated genes and immune infiltrates through the Tumor Immune Estimation Resource (TIMER) database and performed drug–gene interaction analysis using the Drug-Gene Interaction database. A total of 294 specific genes were related to melanoma metastasis and were mainly involved in the positive regulation of locomotion, mitotic cell cycle process, and epithelial cell differentiation. Four hub genes (CDK1, FOXM1, KIF11, and RFC4) were identified from the cytoHubba plugin of Cytoscape. CDK1 was significantly upregulated in metastatic melanoma compared with primary melanoma, and high CDK1 expression was positively correlated with worse overall survival. Immune infiltration analysis revealed that CDK1 expression negatively correlated with macrophage infiltration (Rho = − 0.164, P = 2.02e−03) and positively correlated with neutrophil cells (Rho = 0.269, P = 2.72e−07) in SKCM metastasis. In addition, we identified that CDK1 had a close interaction with 10 antitumor drugs. CDK1 was identified as a hub gene involved in the progression of melanoma metastasis and may be regarded as a therapeutic target for melanoma patients to improve prognosis and prevent metastasis in the future.

The Role of DACT Family Members in Tumorigenesis and Tumor Progression

Disheveled-associated antagonist of β-catenin (DACT), which ubiquitously expressed in human tissue, is critical for regulating cell proliferation and several developmental processes in different cellular contexts. In addition, DACT is essential for some other cellular processes, such as cell apoptosis, migration and differentiation. Given the importance of DACT in these cellular processes, many scientists are gradually interested in studying the role of DACT in tumorigenesis and cancer progression. This review article focuses on the latest research regarding the essential functions and potential DACT mechanisms in the occurrence and progression of tumors. Our study indicates that DACT may act as a tumor biomarker for cancer diagnosis and prognosis, as well as a promising therapeutic target in cancers.

NCAPG promotes tumorigenesis of bladder cancer through NF-κB signaling pathway

The non-SMC condensin I complex subunit G (NCAPG) is a subunit of the condensin complex, many studies have shown that NCAPG is aberrantly expressed in different tumors and closely associated with poor prognosis, but its role in bladder cancer is unclear. In this paper, we found that NCAPG expression was upregulated in bladder cancer in tumor-related databases, and further verified the expression of NCAPG in bladder cancer tissues as well as bladder cancer cell lines by tissue microarray, qPCR, and WB. Next, we explored the changes in bladder cancer cell proliferation as well as migration after NCAPG knockdown by cell growth curve, colony formation, soft agar assay, and xenograft model. Finally, we examined the changes in downstream signaling pathways after NCAPG knockdown using RNA-Seq, and we found that the NF-κB signaling pathway was inhibited with NCAPG gene knockdown, which was verified by luciferase reporter assay as well as WB. In conclusion, our results illustrate that NCAPG knockdown can inhibit the proliferation of bladder cancer cells through the NF-κB signaling pathway. This finding demonstrates that NCAPG could be a potential target for the treatment of bladder cancer.

Phospholipase D1 promotes cervical cancer progression by activating the RAS pathway

This study aimed to further investigate the effect of PLD1 on the biological characteristics of human cervical cancer (CC) cell line, CASKI and the potential related molecular mechanism. CRISPR/Cas9 genome editing technology was used to knock out the PLD1 gene in CASKI cells. Cell function assays were performed to evaluate the effect of PLD1 on the biological function of CASKI cells in vivo and in vitro. A PLD1‐overexpression rescue experiment in these knockout cells was performed to further confirm its function. Two PLD1‐knockout CASKI cell lines (named PC‐11 and PC‐40, which carried the ins1/del4 mutation and del1/del2/ins1 mutation, respectively), were constructed by CRISPR/Cas9. PLD1 was overexpressed in these knockout cells (named PC11‐PLD1 and PC40‐PLD1 cells), which rescued the expression of PLD1 by approximately 71.33% and 74.54%, respectively. In vivo, the cell function assay results revealed that compared with wild‐type (WT)‐CASKI cells, the ability of PC‐11 and PC‐40 cells to proliferate, invade and migrate was significantly inhibited. The expression of H‐Ras and phosphorylation of Erk1/2 (p‐Erk1/2) was decreased in PC‐11 and PC‐40 cells compared with WT‐CASKI cells. PC‐11 and PC‐40 cells could sensitize CASKI cells to cisplatin. More importantly, the proliferation, migration and invasion of PC11‐PLD1 and PC40‐PLD1 cells with PLD1 overexpression were significantly improved compared with those of the two types of PLD1 knockout cells. The sensitivity to cisplatin was decreased in PC11‐PLD1 and PC40‐PLD1 cells compared with PC‐11 and PC‐40 cells. In vivo, in the PC‐11 and PC‐40 tumour groups, tumour growth was significantly inhibited and tumour weight (0.95 ± 0.27 g and 0.66 ± 0.43 g vs. 1.59 ± 0.67 g, p = 0.0313 and 0.0108) and volume (1069.41 ± 393.84 and 1077.72 mm³ ± 815.07 vs. 2142.94 ± 577.37 mm³, p = 0.0153 and 0.0128) were significantly reduced compared to those in the WT‐CASKI group. Tumour differentiation of the PC‐11 and PC40 cells was significantly better than that of the WT‐CASKI cells. The immunohistochemistry results confirmed that the expression of H‐Ras and p‐Erk1/2 was decreased in PC‐11 and PC‐40 tumour tissues compared with WT‐CASKI tumour tissues. PLD1 promotes CC progression by activating the RAS pathway. Inhibition of PLD1 may serve as an attractive therapeutic modality for CC.

DNA Methylome Changes of Muscle- and Neuronal-Related Processes Precede Bladder Cancer Invasiveness

Bladder cancer (BC) is the ninth leading cause of cancer death with one of the highest recurrence rates among all cancers. One of the main risks for BC development is exposure to nitrosamines present in tobacco smoke or in other products. Aberrant epigenetic (DNA methylation) changes accompanied by deregulated gene expression are an important element of cancer pathogenesis. Therefore, we aimed to determine DNA methylation signatures and their impacts on gene expression in mice treated with N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN), a carcinogen similar to compounds found in tobacco smoke. Following BBN administration mice developed non-invasive or invasive bladder cancers. Surprisingly, muscle- and neuronal-related pathways emerged as the most affected in those tumors. Hypo- and hypermethylation changes were present within non-invasive BC, across CpGs mapping to the genes involved in muscle- and neuronal-related pathways, however, methylation differences were not sufficient to affect the expression of the majority of associated genes. Conversely, invasive tumors displayed hypermethylation changes that were linked with alterations in gene expression profiles. Together, these findings indicate that bladder cancer progression could be revealed through methylation profiling at the pre-invasive cancer stage that could assist monitoring of cancer patients and guide novel therapeutic approaches.

Exploration study on serum metabolic profiles of Chinese male patients with artificial stone silicosis, silicosis, and coal worker's pneumoconiosis

Long-term exposure to inhaled silica dust induces pneumoconiosis, which remains a heavy burden in developing countries. Modern industry provides new resources of occupational SiO₂ leading to artificial stone silicosis especially in developed countries. This study aimed to characterize the serum metabolic profile of pneumoconiosis and artificial stone silicosis patients. Our case-control study recruited 46 pairs of pneumoconiosis patients and dust-exposed workers. Nontargeted metabolomics and lipidomics by ultra-high-performance liquid chromatography-tandem mass spectrometry platform were conducted to characterize serum metabolic profile in propensity score-matched (PSM) pilot study. 54 differential metabolites were screened, 24 of which showed good screening efficiency through receiver operating characteristics (ROC) in pilot study and validation study (both AUC > 0.75). 4 of the 24 metabolites can predict pneumoconiosis stages, which are 1,2-dioctanoylthiophosphatidylcholine, phosphatidylcholine(O-18:1/20:1), indole-3-acetamide and l-homoarginine. Kynurenine, N-tetradecanoylsphingosine 1-phosphate, 5-methoxytryptophol and phosphatidylethanolamine(22:6/18:1) displayed the potential as specific biomarkers for artificial stone silicosis. Taken together, our results confirmed that tryptophan metabolism is closely related to pneumoconiosis and may be related to disease progression. Hopefully, our results could supplement the biomarkers of pneumoconiosis and provide evidence for the discovery of artificial stone silicosis-specific biomarkers.