Exosomal circRHCG promotes breast cancer metastasis via facilitating M2 polarization through TFEB ubiquitination and degradation.

Triple-negative breast cancer (TNBC) is a highly aggressive cancer with distant metastasis. Accumulated evidence has demonstrated that exosomes are involved in TNBC metastasis. Elucidating the mechanism underlying TNBC metastasis has important clinical significance. In the present study, exosomes were isolated from clinical specimens and TNBC cell lines. Colony formation, EdU incorporation, wound healing, and transwell assays were performed to examine TNBC cell proliferation, migration, and metastasis. Macrophage polarization was evaluated by flow cytometry and RT-qPCR analysis of polarization markers. A mouse model of subcutaneous tumor was established for assessment of tumor growth and metastasis. RNA pull-down, RIP and Co-IP assays were used for analyzing molecular interactions. Here, we proved that high abundance of circRHCG was observed in exosomes derived from TNBC patients, and increased exosomal circRHCG indicated poor prognosis. Silencing of circRHCG suppressed TNBC cell proliferation, migration, and metastasis. TNBC cell-derived exosomes promoted M2 polarization via delivering circRHCG. Exosomal circRHCG stabilized BTRC mRNA via binding FUS and naturally enhanced BTRC expression, thus promoting the ubiquitination and degradation of TFEB in THP-1 cells. In addition, knockdown of BTRC or overexpression of TFEB counteracted exosomal circRHCG-mediated facilitation of M2 polarization. Furthermore, exosomal circRHCG promoted TNBC cell proliferation and metastasis by facilitating M2 polarization. Knockdown of circRHCG reduced tumor growth, metastasis, and M2 polarization through the BTRC/TFEB axis in vivo. In summary, exosomal circRHCG promotes M2 polarization by stabilizing BTRC and promoting TFEB degradation, thereby accelerating TNBC metastasis and growth. Our study provides promising therapeutic strategies against TNBC.

Integration of bioinformatics and machine learning strategies identifies APM-related gene signatures to predict clinical outcomes and therapeutic responses for breast cancer patients.

BACKGROUND: Tumor antigenicity and efficiency of antigen presentation jointly influence tumor immunogenicity, which largely determines the effectiveness of immune checkpoint blockade (ICB). However, the role of altered antigen processing and presentation machinery (APM) in breast cancer (BRCA) has not been fully elucidated. METHODS: A series of bioinformatic analyses and machine learning strategies were performed to construct APM-related gene signatures to guide personalized treatment for BRCA patients. A single-sample gene set enrichment analysis (ssGSEA) algorithm and weighted gene co-expression network analysis (WGCNA) were combined to screen for BRCA-specific APM-related genes. The non-negative matrix factorization (NMF) algorithm was used to divide the cohort into different clusters and the fgsea algorithm was applied to investigate the altered signaling pathways. Random survival forest (RSF) and the least absolute shrinkage and selection operator (Lasso) Cox regression analysis were combined to construct an APM-related risk score (APMrs) signature to predict overall survival. Furthermore, a nomogram and decision tree were generated to improve predictive accuracy and risk stratification for individual patients. Based on Tumor Immune Dysfunction and Exclusion (TIDE) method, random forest (RF) and Lasso logistic regression model were combined to establish an APM-related immunotherapeutic response score (APMis). Finally, immune infiltration, immunomodulators, mutational patterns, and potentially applicable drugs were comprehensively analyzed in different APM-related risk groups. IHC staining was used to assess the expression of APM-related genes in clinical samples. RESULTS: In this study, APMrs and APMis showed favorable performances in risk stratification and therapeutic prediction for BRCA patients. APMrs exhibited more powerful prognostic capacity and accurate survival prediction compared to conventional clinicopathological features. APMrs was closely associated with distinct mutational patterns, immune cell infiltration and immunomodulators expression. Furthermore, the two APM-related gene signatures were independently validated in external cohorts with prognosis or immunotherapeutic responses. Potential applicable drugs and targets were mined in the APMrs-high group. APM-related genes were further validated in our in-house samples. CONCLUSION: The APM-related gene signatures established in our study could improve the personalized assessment of survival risk and guide ICB decision-making for BRCA patients.

Single-cell RNA sequencing reveals new subtypes of lens superficial tissue in humans.

Although the cell atlas of the human ocular anterior segment of the human eye was revealed by single-nucleus RNA sequencing, whether subtypes of lens stem/progenitor cells exist among epithelial cells and the molecular characteristics of cell differentiation of the human lens remain unclear. Single-cell RNA sequencing is a powerful tool to analyse the heterogeneity of tissues at the single cell level, leading to a better understanding of the processes of cell differentiation. By profiling 18,596 cells in human lens superficial tissue through single-cell sequencing, we identified two subtypes of lens epithelial cells that specifically expressed C8orf4 and ADAMTSL4 with distinct spatial localization, a new type of fibre cells located directly adjacent to the epithelium, and a subpopulation of ADAMTSL4+ cells that might be lens epithelial stem/progenitor cells. We also found two trajectories of lens epithelial cell differentiation and changes of some important genes during differentiation.

Glucose metabolism and lncRNAs in breast cancer: Sworn friend.

BACKGROUND: Glucose metabolism disorder is a common feature in cancer. Cancer cells generate much energy through anaerobic glycolysis, which promote the development of tumors. However, long non-coding RNA may play an important role in this process. Our aim is to explore a prognostic risk model based on the glucose metabolism-related lncRNAs which provides clues that lncRNAs predict a clinical outcome through glucose metabolism in breast cancer. METHODS: 1222 RNA-seq were extracted from the TCGA database, and 74 glucose metabolism-related genes were loaded from the GSEA website. Then, 7 glucose metabolism-related lncRNAs risk score model was developed by univariate, Lasso, and multivariate regression analysis. The lncRNA risk model showed that high-risk patients predict a poor clinical outcome with high reliability (P=2.838×10-6). Univariate and multivariate independent prognostic analysis and ROC curve analysis proved that the risk score was an independent prognostic factor in breast cancer with an AUC value of 0.652. Finally, Gene set enrichment analysis showed that cell cycle-related pathways were significantly enriched in a high-risk group. RESULTS: Our results showed that glucose metabolism-related lncRNAs can affect breast cancer progression. 7 glucose metabolism-related lncRNAs prognostic signature was established to evaluate the OS of patients with breast cancer. PICSAR, LINC00839, AP001505.1, LINC00393 were risk factors and expressed highly in the high-risk group. A Nomogram was made based on this signature to judge patients' living conditions and prognosis. CONCLUSION: 7 glucose metabolism-related lncRNAs risk score model had a high prognostic value in breast cancer. PICSAR, LINC00839, AP001505.1, LINC00393 were risk factors. AP001505.1 expression was increased in most triple-negative breast cancer cells treated with high glucose, which may also take part in breast cancer progression and potential therapeutic targets.

Roles and mechanisms of miR-195-5p in human solid cancers.

Cancer persists as a worldwide disease that contributes to high morbidity and mortality rates. As a class of non-coding RNA, microRNAs (miRNAs) are one kind of important regulators in cancer and frequently implicated in tumor development and progression. Emerging experiments have suggested that miRNA-195-5p (miR-195-5p) can regulate neoplastic processes in many pathways. For instance, miR-195-5p can not only regulate proliferation, migration and invasion of tumor cells but also promote tumor cell apoptosis. Furthermore, low expression of miR-195-5p could induce drug resistance. Our review focuses on the expression of miR-195-5p in various tumors and elucidates the related mechanisms of which miR-195-5p participates in tumor biology, as well as summarizes the roles of miR-195-5p in tumor progression. We believe that miR-195-5p might have potential utility as a novel diagnostic biomarker and therapeutic target for cancer.

Exosomal circRNAs: a new communication method in cancer.

Exosomes are extracellular vesicles with unique membrane markers and components that participate in cellular communication. The contents of exosomes, including growth factors, microRNAs, long noncoding RNAs, and circular RNAs (circRNAs), have been recognized as prognostic biomarkers and promote cancer progression through cancer cell growth, metastasis, angiogenesis, and cancer development. One of the components of exosomes, circRNAs, are covalently closed and prevented from degrading, which results in their continually accumulating in exosomes. Evidence suggests that exosomal circRNAs are abundant and stable in body fluids and have been implicated in many diseases. In this article we summarize the biogenesis and function of circRNAs and explore the expressions of exosomal circRNAs in cancer, emphasizing the fact that exosomal circRNAs are a novel diagnostic biomarker in the early stages of cancer and/or a therapeutic target in further cancer treatment.

Hepatocyte-specific deletion of BAP31 promotes SREBP1C activation, promotes hepatic lipid accumulation, and worsens IR in mice.

Conditional knockout mice with targeted disruption of B-cell associated protein (BAP)31 in adult mouse liver were generated and challenged with a high-fat diet (HFD) for 36 or 96 days and markers of obesity, diabetes, and hepatic steatosis were determined. Mutant mice were indistinguishable from WT littermates, but exhibited increased HFD-induced obesity. BAP31-deletion in hepatocytes increased the expression of SREBP1C and the target genes, including acetyl-CoA carboxylase 1 and stearoyl-CoA desaturase-1, and increased hepatic lipid accumulation and HFD-induced liver steatosis. Immunoprecipitation assay showed that BAP31 interacts with SREBP1C and insulin-induced gene 1 (INSIG1), and BAP31-deletion reduces INSIG1 expression, suggesting that BAP31 may regulate SREBP1C activity by modulating INSIG1 protein levels. Additionally, BAP31-deletion induced glucose and insulin intolerance, decreased Akt and glycogen synthase kinase 3ß phosphorylation, and enhanced hepatic glucose production in mice. Expression of endoplasmic reticulum (ER) stress markers was significantly induced in BAP31-mutant mice. HFD-induced inflammation was aggravated in mutant mice, along with increased c-Jun N-terminal kinase and nuclear factor-κB activation. These findings demonstrate that BAP31-deletion induces SREBP activation and promotes hepatic lipid accumulation, reduces insulin signaling, impairs glucose/insulin tolerance, and increases ER stress and hepatic inflammation, explaining the protective roles of BAP31 in the development of liver steatosis and insulin resistance in HFD-induced obesity in animal models.

Preclinical assessment of the distribution, metabolism, and excretion of S-propargyl-cysteine, a novel H2S donor, in Sprague-Dawley rats.

AIM: To study the distribution, metabolism and excretion of S-propargyl-cysteine (SPRC), a novel hydrogen sulfide (H2S) donor, after oral administration in rats. METHODS: Adult Sprague-Dawley rats were used. The tissue distribution of [(35)S] SPRC-derived radioactivity was measured using a liquid scintillation counter. The plasma protein binding of SPRC was examined using 96-well equilibrium dialysis. The excretion of SPRC in urine, bile and feces was analyzed using the LC-MS/MS method. The major metabolites in rat biomatrices were identified using MRM information-dependent, acquisition-enhanced product ion (MRM-IDA-EPI) scans on API 4000QTrap system. RESULTS: After oral administration of [(35)S]-SPRC at a dose of 75 mg/kg, [(35)S] SPRC-derived radioactivity displayed broad biological distribution in various tissues of rats, including its target organs (heart and brain) with the highest in kidney. On the other hand, the binding of SPRC to human, rat and dog plasma protein was low. Only 2.18% ± 0.61% and 0.77% ± 0.61% of the total SPRC administered was excreted unchanged in the bile and urine. However, neither intact SPRC nor its metabolites were detected in rat feces. The major metabolic pathway in vivo (rat bile, urine, and plasma) was N-acetylation. CONCLUSION: The preliminary results suggest that SPRC possesses acceptable pharmacokinetic properties in rats.

[The three-dimension spectral subtraction fluorescence to check adulteration of diesel oil by 120# solvent naphtha].

The characteristics of a adulterated sample of diesel oil by 120# solvent naphtha were studied with three-dimension spectral subtraction fluorescence technique, and it is shown that the technique could determine quickly whether there is a adulterated sample of 120# solvent naphtha in diesel. At the same time, by measuring the volume of three-dimension spectral subtraction fluorescence graph, the authors found that this total volume is directly related to the concentration of the adulterant present in the sample. The study is important for us to analyse whether there is a adulterated sample of 120# solvent naphtha in diesel, and is of significance for us to maintain the stability of market.

[Study of poly (3,4-ethylene dioxythiophene) : poly (styrene sulfonate) by in-situ resonance Raman spectroscopy].

Poly (3,4-ethylene dioxythiophene) (PEDOT): Poly (styrene sulfonate) (PSS) has attracted a lot of interest for application in organic electronics due to good stability and high electronic conductivity in its doped state. Indeed, thin layers of PEDOT:PSS was regularly used in light emitting diodes (PLEDs) as hole injection and transportation layer. Here, Doping and dedoping states of PEDOT:PSS were studied by absorbance spectra and Raman spectra. A new absorption band centered at 620 nm was observed on dedoped PEDOT:PSS. Consistently, Raman signals of dedoped PEDOT:PSS are resonantly intensified since the Raman excitation wavelength (633 nm) is set in the enhanced absorption band. So it gives a sensitive way to study the doping and dedoping states of PEDOT:PSS. Furthermore, for the encapsulated polymer light-emitting diodes, Raman spectroscopy is a powerful way to study the polymer layers inside the devices.