Heterogeneous matrix stiffness regulates the cancer stem-like cell phenotype in hepatocellular carcinoma.

BACKGROUND: Solid tumors are stiffer than their surrounding normal tissues; however, their interior stiffness is not uniform. Under certain conditions, cancer cells can acquire stem-like phenotypes. However, it remains unclear how the heterogeneous physical microenvironment affects stemness expression in cancer cells. Here, we aimed to evaluate matrix stiffness heterogeneity in hepatocellular carcinoma (HCC) tissues and to explore the regulation effect of the tumor microenvironment on stem-like phenotypic changes through mechanical transduction. METHODS: First, we used atomic force microscopy (AFM) to evaluate the elastic modulus of HCC tissues. We then used hydrogel with adjustable stiffness to investigate the effect of matrix stiffness on the stem-like phenotype expression of HCC cells. Moreover, cells cultured on hydrogel with different stiffness were subjected to morphology, real-time PCR, western blotting, and immunofluorescence analyses to explore the mechanotransduction pathway. Finally, animal models were used to validate in vitro results. RESULTS: AFM results confirmed the heterogenous matrix stiffness in HCC tissue. Cancer cells adhered to hydrogel with varying stiffness (1.10 ± 0.34 kPa, 4.47 ± 1.19 kPa, and 10.61 kPa) exhibited different cellular and cytoskeleton morphology. Higher matrix stiffness promoted the stem-like phenotype expression and reduced sorafenib-induced apoptosis. In contrast, lower stiffness induced the expression of proliferation-related protein Ki67. Moreover, mechanical signals were transmitted into cells through the integrin-yes-associated protein (YAP) pathway. Higher matrix stiffness did not affect YAP expression, however, reduced the proportion of phosphorylated YAP, promoted YAP nuclear translocation, and regulated gene transcription. Finally, application of ATN-161 (integrin inhibitor) and verteporfin (YAP inhibitor) effectively blocked the stem-like phenotype expression regulated by matrix stiffness. CONCLUSIONS: Our experiments provide new insights into the interaction between matrix stiffness, cancer cell stemness, and heterogeneity, while also providing a novel HCC therapeutic strategy.

Identification of cuproptosis-related long non-coding RNA and construction of a novel prognostic signature for bladder cancer: An observational study.

Bladder Urothelial Carcinoma (BLCA), a prevalent and lethal cancer, lacks understanding regarding the roles and prognostic value of cuproptosis-related lncRNAs (CRLs), a novel form of cell death induced by copper. We collected RNA-seq data, clinical information, and prognostic data for 414 BLCA samples and 19 matched controls from The Cancer Genome Atlas. Using multivariate and univariate Cox regression analyses, we identified CRLs to create a prognostic signature. Patients were then divided into low- and high-risk groups based on their risk scores. We analyzed overall survival using the Kaplan-Meier method, evaluated stromal and immune scores, and explored functional differences between these risk groups with gene set enrichment analysis. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were also conducted to understand the links between CRLs and BLCA development. We developed a prognostic signature using 4 independent CRLs: RC3H1-IT1, SPAG5-AS1, FAM13A-AS1, and GNG12-AS1. This signature independently predicted the prognosis of BLCA patients. High-risk patients had worse outcomes, with gene set enrichment analysis revealing enrichment in tumor- and immune-related pathways in the high-risk group. Notably, high-risk patients exhibited enhanced responses to immunotherapy and conventional chemotherapy drugs like sunitinib, paclitaxel, and gemcitabine. The independent prognostic signature variables RC3H1-IT1, SPAG5-AS1, FAM13A-AS1, and GNG12-AS1 predicted the prognoses of BLCA patients and provided a basis for the study of the mechanism of CRLs in BLCA development and progression, and the guidance of clinical treatments for patients with BLCA.

Itaconate attenuates autoimmune hepatitis via PI3K/AKT/mTOR pathway-mediated inhibition of dendritic cell maturation and autophagy.

Autoimmune hepatitis (AIH) results from an autoimmune-mediated chronic inflammatory response against liver cells. Defective self-tolerance and dysfunctional dendritic cells (DCs) play a regulatory role in AIH. Itaconate has recently attracted attention in the field of immunometabolism because of its crucial role as an anti-inflammatory metabolite that negatively regulates the inflammatory response. However, the underlying mechanism of itaconate mediation of DCs in AIH remains unclear. In this study, we found that itaconate acts as an anti-inflammatory factor in the liver. Endogenous itaconate levels were significantly increased in mice with S100-induced AIH model and correlated with upregulation of the immune-responsive gene 1 expression. However, the anti-inflammatory response from endogenously itaconate may not represent the effects exogenously-produced itaconate. We investigated the anti-inflammatory response from exogenous itaconate in S100-induced AIH, and our results showed that itaconate treatment attenuated liver histopathological damage, hepatocyte apoptosis, aminotransferase elevation, and IL-6 production in the S100-induced AIH model. In addition, Itaconate decreased glycolysis to suppress the maturation of DCs in the liver and spleen of AIH models, thereby directly regulating differentiation of Th17 and Tregs in vivo. The percentage of Th17 cells among the CD4+ population were decreased and Tregs were increased (P < 0.05). Furthermore, Itaconate-induced bone marrow-derived monocytes suppressed CD4+cells proliferation. In vitro and in vivo, we found that itaconate suppressed autophagy via activating the PI3K/AKT/mTOR signalling pathway in bone marrow-derived DCs and liver tissues. We further investigated the function of Itaconate on DC-specific mTOR-deficient mice. mTOR-deficient DCs augmented inflammatory reactions in mTORDC-/- AIH mice and induced autophagy. MHY1485 (an agonist of mTOR) and itaconate significantly alleviated the inflammatory reaction and autophagy signalling. In conclusion, itaconate ameliorate liver inflammation in S100-induced AIH mice by regulating the PI3K/AKT/mTOR pathway to decrease DCs autophagy and maturation. These results provide insight useful for treating AIH.

Cell Therapy for Androgenetic Alopecia: Elixir or Trick?

Androgenetic alopecia is the most common cause of hair loss aggravated by increased life pressure, tension, and anxiety. Although androgenetic alopecia (AGA) does not significantly effect physical health, it can have serious negative impact on the mental health and quality of life of the patient. Currently, the effect of medical treatment for AGA is not idealistic, stem cell-based regenerative medicine has shown potential for hair regrowth and follicle repair, but the long-term effect and mechanism of stem cell therapy is not quite explicit. In this review, we summarize the methods, efficacy, mechanism, and clinical progress of stem cell therapies for AGA by now, hope it will present a more comprehensive view in this topic.

Chemical characterization of Tianshan green tea polysaccharides and its protective effects on cell oxidative injury.

The purpose of this study was to analyze the chemical characterization of Tianshan green tea polysaccharides (TSPS), and evaluate its antioxidant activity by chemical-based and cellular-based antioxidant models in vitro. The results showed that the TSPS were composed of mannose, ribose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, arabinose, and fucose with a molar ratio of 14.5:33.5:10.5:6.5:111.5:22.3:59.5:51: 1.0, and an average molecular weight of 19.49 kDa. TSPS exhibited excellent antioxidant ability to DPPH radical, hydroxyl radical, and ABTS radical, and enhanced the ferric-reducing power (FRAP). The antioxidation model of LO2 and HepG2 cells was established, and found that TSPS had no significant toxicity to either of the two cells at the range of 0.1-5 mg/mL, but clearly protected cells from H2 O2 -induced apoptosis and significantly reduced intracellular ROS level. In addition, the activities of antioxidant-associated enzymes were detected in LO2 cells, which suggested that TSPS could significantly improve the activities of SOD and CAT enzyme when the concentration was higher than 0.5 mg/mL. Furthermore, TSPS activated the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway by promoting Nrf2 nuclear translocation and inhibited the expression of Kelch-like ECH-associated protein 1 (Keap-1) and enhanced the expression of heme oxygenase-1 (HO-1). PRACTICAL APPLICATIONS: Tianshan green tea, a local variety in Fujian Province, belongs to unfermented tea. Polysaccharide is considered as the most promising component in Tianshan green tea. This study showed that TSPS had excellent antioxidant activity and had no significant toxicity to cells, which provides a scientific foundation and new idea for its further development and application in functional foods.

In vivo and in vitro performances of chitosan-coated Mg-Zn-Zr-Gd-Ca alloys as bone biodegradable materials in rat models.

Mg alloys have attracted significant attention as promising biomedical materials, specifically as fixation materials for promoting fracture healing. However, their unsatisfactory corrosion resistances hinder further clinical applications and thus require attention. This study aims to determine the performance of novel chitosan-coated Mg-1Zn-0.3Zr-2Gd-1Ca alloy and its ability to promote the healing of osteoporotic fractures. Moreover, its corrosion resistance and biocompatibility were assessed. Performance degradations of the samples were measured via electrochemical tests, weight loss test and morphological analysis, and the uncoated and chitosan-coated fixations were compared based on their effects on biocompatibility via the cytotoxicity test, X-rays, and hematoxylin and eosin staining. The effect of bone growth and healing was investigated via immunohistochemical test. Results of the electrochemical tests indicated that compared with the bare body, chitosan-coated Mg-Zn-Ca-Zr-Gd alloys improved by one order of magnitude. Additionally, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and weight loss test demonstrated that the corrosion resistance of the chitosan-coated Mg alloy is better than that of the uncoated alloy. In addition, cytotoxicity analysis indicated that the viability and morphology of the chitosan-coated alloy groups were superior to the uncoated groups in vitro. During in vivo analysis, chitosan-coated and uncoated Mg-1Zn-0.3Zr-2Gd-1Ca alloys were implanted into ovariectomized SD female rats with osteoporotic fractures for 1, 2, and 3 weeks. No displacement and shedding were observed through X-rays, and pathological analyses proved that the material was not harmful for liver and kidney tissues. Immunohistochemistry revealed that the chitosan-coated Mg-Zn-Ca-Zr-Gd alloy material contributed to the healing of osteoporotic fractures in the SD rat models. In conclusion, this study demonstrated the chitosan-coated Mg-Zn-Ca-Zr-Gd alloys have improved corrosion resistance and biocompatibility. Moreover, the alloy was found to accelerate the healing of osteoporotic fractures in SD rat models. Therefore, it has significant potential as a fixation material for osteoporotic fractures.

Corrosion and biocompatibility behaviours of microarc oxidation/phytic acid coated magnesium alloy clips for use in cholecystectomy in a rabbit model.

With the popularisation of laparoscopic cholecystectomy, ligation clips have been commonly used for ligating the cystic duct and cystic artery. However, non-degradable clips remain in the body long-term, which significantly increases the risk of the clip becoming detached. Thus, magnesium alloys have attracted tremendous attention owing to their biodegradability and good biocompatibility. However, the poor corrosion resistance hinders the clinical application of magnesium alloys with microarc oxidation/phytic acid (MAO/PA) composite coatings as protective coatings. Here, these alloys were used to hinder the rapid material degradation in aqueous solution. Electrochemical tests were conducted to evaluate the in vivo degradation behaviour in simulated body fluid (SBF) for Mg-Zn-Y-Nd alloys, and scanning electron microscopy (SEM) was used to observe the micromorphology of in vivo clip degradation. Cell toxicity, cell adhesion, and flow cytometry were performed in vitro to detect cytocompatibility. Biochemical detection of serum magnesium, serum creatinine (CREA), blood urea nitrogen (BUN), alanine transaminase (ALT), and alanine aminotransferase (AST), and haematoxylin-eosin (HE) staining of the heart, liver, and kidney tissues in vivo was conducted to determine the biocompatibility properties after surgery. Electrochemical measurements and SEM images revealed that the MAO/PA-coated magnesium alloy delayed corrosion in SBF. The apoptosis rate increased slightly with increased extract concentration. Nevertheless, MAO/PA-coated magnesium alloys still exhibited good cytocompatibility. No obvious abnormality was observed in the blood biochemical test or HE staining. Thus, MAO/PA-coated magnesium alloys exhibit better corrosion than bare magnesium. In addition, Mg-Zn-Y-Nd and MAO/PA-coated magnesium alloys exhibited no cytotoxicity, good adhesion, and biosafety.

Biological behavior exploration of a paclitaxel-eluting poly-l-lactide-coated Mg-Zn-Y-Nd alloy intestinal stent in vivo.

As a new type of intestinal stent, the MAO/PLLA/paclitaxel/Mg-Zn-Y-Nd alloy stent has shown good degradability, although its biocompatibility in vitro and in vivo has not been investigated in detail. In this study, its in vivo biocompatibility was evaluated by animal study. New Zealand white rabbits were implanted with degradable intestinal Mg-Zn-Y-Nd alloy stents that were exposed to different treatments. Stent degradation behavior was observed both macroscopically and using a scanning electron microscope (SEM). Energy dispersion spectrum (EDS) and histological observations were performed to investigate stent biological safety. Macroscopic analysis showed that the MAO/PLLA/paclitaxel/Mg-Zn-Y-Nd stents could not be located 12 days after implantation. SEM observations showed that corrosion degree of the MAO/PLLA/paclitaxel/Mg-Zn-Y-Nd stents implanted in rabbits was significantly lower than that in the PLLA/Mg-Zn-Y-Nd stent group. Both histopathological testing and serological analysis of in vivo biocompatibility demonstrated that the MAO/PLLA/paclitaxel/Mg-Zn-Y-Nd alloy stents could significantly inhibit intestinal tissue proliferation compared to the PLLA/Mg-Zn-Y-Nd alloy stents, thus providing the basis for designing excellent biodegradable drug stents.

Correction: Biological behavior exploration of a paclitaxel-eluting poly-l-lactide-coated Mg-Zn-Y-Nd alloy intestinal stent in vivo.

[This corrects the article DOI: 10.1039/C9RA10156J.].

[Isolation and identification of SARS virus in Guangdong province].

BACKGROUND: To isolate and identify pathogen of atypical pneumonia in Guangdong. METHODS: Pathogens were isolated from variety of samples collected from atypical pneumonia patient by using MDCK cells, and identified with serological and molecular methods. RESULTS: A novel coronavirus was isolated from patients with atypical pneumonia, from which an RNA fragment of 279 nt was amplified by nested RT-PCR. And sequence assay showed that only 39-65 percent of sequence of the virus was homogenous to known coronavirus, but almost 100% homogenous (with one base exception, 12a to t) to SARS-associated coronavirus isolated from patients outside Guangdong, such as in Beijing, Hong Kong, Taiwan, Germany, Italy and so on. Indirect immunofluorescence test showed a specific antigen-antibody reactivity between the coronavirus and convalescent-phase sera of SARS patients. CONCLUSION: The pathogen of the atypical pneumonia in Guangdong province was a novel type of coronavirus, which could be isolated by using MDCK cells.