Specific and efficient knockdown of intracellular miRNA using partially neutralized phosphate-methylated DNA oligonucleic acid-loaded mesoporous silica nanoparticles.

Antisense oligonucleotides (ASOs) are molecules used to regulate RNA expression by targeting specific RNA sequences. One specific type of ASO, known as neutralized DNA (nDNA), contains site-specific methyl phosphotriester (MPTE) linkages on the phosphate backbone, changing the negatively charged DNA phosphodiester into a neutralized MPTE with designed locations. While nDNA has previously been employed as a sensitive nucleotide sequencing probe for the PCR, the potential of nDNA in intracellular RNA regulation and gene therapy remains underexplored. Our study aims to evaluate the regulatory capacity of nDNA as an ASO probe in cellular gene expression. We demonstrated that by tuning MPTE locations, partially and intermediately methylated nDNA loaded onto mesoporous silica nanoparticles (MSNs) can effectively knock down the intracellular miRNA, subsequently resulting in downstream mRNA regulation in colorectal cancer cell HCT116. Additionally, the nDNA ASO-loaded MSNs exhibit superior efficacy in reducing miR-21 levels over 72 hours compared to the efficacy of canonical DNA ASO-loaded MSNs. The reduction in the miR-21 level subsequently resulted in the enhanced mRNA levels of tumour-suppressing genes PTEN and PDCD4. Our findings underscore the potential of nDNA in gene therapies, especially in cancer treatment via a fine-tuned methylation location.

The protective effect of cannabinoids against colorectal cancer cachexia through modulation of inflammation and immune responses.

Cancer cachexia is a multifactorial disorder characterized by weight loss and muscle wasting, and there are currently no FDA-approved medications. In the present study, upregulation of six cytokines was observed in serum samples from patients with colorectal cancer (CRC) and in mouse models. A negative correlation between the levels of the six cytokines and body mass index in CRC patients was seen. Gene Ontology analysis revealed that these cytokines were involved in regulating T cell proliferation. The infiltration of CD8+ T cells was found to be associated with muscle atrophy in mice with CRC. Adoptive transfer of CD8+ T cells isolated from CRC mice resulted in muscle wasting in recipients. The Genotype-Tissue Expression database showed that negative correlations between the expression of cachexia markers and cannabinoid receptor 2 (CB2) in human skeletal muscle tissues. Pharmacological treatment with Δ9-tetrahydrocannabinol (Δ9-THC), a selective CB2 agonist or overexpression of CB2 attenuated CRC-associated muscle atrophy. In contrast, knockout of CB2 with a CRISPR/Cas9-based strategy or depletion of CD8+ T cells in CRC mice abolished the Δ9-THC-mediated effects. This study demonstrates that cannabinoids ameliorate CD8+ T cell infiltration in CRC-associated skeletal muscle atrophy via a CB2-mediated pathway. Serum levels of the six-cytokine signature might serve as a potential biomarker to detect the therapeutic effects of cannabinoids in CRC-associated cachexia.

Rapid and Accurate Detection of SARS Coronavirus 2 by Nanopore Amplicon Sequencing.

Objective: We aimed to evaluate the performance of nanopore amplicon sequencing detection for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in clinical samples. Method: We carried out a single-center, prospective cohort study in a Wuhan hospital and collected a total of 86 clinical samples, including 54 pharyngeal swabs, 31 sputum samples, and 1 fecal sample, from 86 patients with coronavirus disease 2019 (COVID-19) from Feb 20 to May 15, 2020. We performed parallel detection with nanopore-based genome amplification and sequencing (NAS) on the Oxford Nanopore Technologies (ONT) minION platform and routine reverse transcription quantitative polymerase chain reaction (RT-qPCR). In addition, 27 negative control samples were detected using the two methods. The sensitivity and specificity of NAS were evaluated and compared with those of RT-qPCR. Results: The viral read number and reference genome coverage were both significantly different between the two groups of samples, and the latter was a better indicator for SARS-CoV-2 detection. Based on the reference genome coverage, NAS revealed both high sensitivity (96.5%) and specificity (100%) compared with RT-qPCR (80.2 and 96.3%, respectively), although the samples had been stored for half a year before the detection. The total time cost was less than 15 h, which was acceptable compared with that of RT-qPCR (∼2.5 h). In addition, the reference genome coverage of the viral reads was in line with the cycle threshold value of RT-qPCR, indicating that this number could also be used as an indicator of the viral load in a sample. The viral load in sputum might be related to the severity of the infection, particularly in patients within 4 weeks after onset of clinical manifestations, which could be used to evaluate the infection. Conclusion: Our results showed the high sensitivity and specificity of the NAS method for SARS-CoV-2 detection compared with RT-qPCR. The sequencing results were also used as an indicator of the viral load to display the viral dynamics during infection. This study proved the wide application prospect of nanopore sequencing detection for SARS-CoV-2 and may more knowledge about the clinical characteristics of COVID-19.

A chemical probe inhibitor targeting STAT1 restricts cancer stem cell traits and angiogenesis in colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) is a worldwide cancer with rising annual incidence. New medications for patients with CRC are still needed. Recently, fluorescent chemical probes have been developed for cancer imaging and therapy. Signal transducer and activator of transcription 1 (STAT1) has complex functions in tumorigenesis and its role in CRC still needs further investigation. METHODS: RNA sequencing datasets in the NCBI GEO repository were analyzed to investigate the expression of STAT1 in patients with CRC. Xenograft mouse models, tail vein injection mouse models, and azoxymethane/dextran sodium sulfate (AOM/DSS) mouse models were generated to study the roles of STAT1 in CRC. A ligand-based high-throughput virtual screening approach combined with SWEETLEAD chemical database analysis was used to discover new STAT1 inhibitors. A newly designed and synthesized fluorescently labeled 4',5,7-trihydroxyisoflavone (THIF) probe (BODIPY-THIF) elucidated the mechanistic actions of STAT1 and THIF in vitro and in vivo. Colonosphere formation assay and chick chorioallantoic membrane assay were used to evaluate stemness and angiogenesis, respectively. RESULTS: Upregulation of STAT1 was observed in patients with CRC and in mouse models of AOM/DSS-induced CRC and metastatic CRC. Knockout of STAT1 in CRC cells reduced tumor growth in vivo. We then combined a high-throughput virtual screening approach and analysis of the SWEETLEAD chemical database and found that THIF, a flavonoid abundant in soybeans, was a novel STAT1 inhibitor. THIF inhibited STAT1 phosphorylation and might bind to the STAT1 SH2 domain, leading to blockade of STAT1-STAT1 dimerization. The results of in vitro and in vivo binding studies of THIF and STAT1 were validated. The pharmacological treatment with BODIPY-THIF or ablation of STAT1 via a CRISPR/Cas9-based strategy abolished stemness and angiogenesis in CRC. Oral administration of BODIPY-THIF attenuated colitis symptoms and tumor growth in the mouse model of AOM/DSS-induced CRC. CONCLUSIONS: This study demonstrates that STAT1 plays an oncogenic role in CRC. BODIPY-THIF is a new chemical probe inhibitor of STAT1 that reduces stemness and angiogenesis in CRC. BODIPY-THIF can be a potential tool for CRC therapy as well as cancer cell imaging.

Cannabinoids orchestrate cross-talk between cancer cells and endothelial cells in colorectal cancer.

Medical marijuana has been approved by the FDA for treating chemotherapy-induced nausea and vomiting. However, less is known about its direct effects on tumor cells and the tumor microenvironment. In this study, RNA-sequencing datasets in the NCBI GEO repository were first analyzed; upregulation of cannabinoid receptors was observed in both primary and metastatic colorectal cancer (CRC) tumor tissues. An increase of cannabinoid receptors was also found in patients with CRC, azoxymethane/dextran sulfate sodium-induced CRC and CRC metastatic mouse models. Δ9-Tetrahydrocannabinol (Δ9-THC)-induced tumor progression in both primary and metastatic mouse models and also increased angiogenesis. A human growth factor antibody array indicated that Δ9-THC promoted the secretion of angiogenic growth factors in CRC, leading to the induction of tube formation and migration in human-induced pluripotent stem cell-derived vascular endothelial cells. The nuclear translocation of STAT1 played important roles in Δ9-THC-induced angiogenesis and tumor progression. Pharmacological treatment with STAT1 antagonist or abrogation of STAT1 with CRISPR/Cas9-based strategy rescued those effects of Δ9-THC in CRC. This study demonstrates that marijuana might increase the risk of CRC progression and that inhibition of STAT1 is a potential strategy for attenuating these side effects.

Resveratrol benefits the lineage commitment of bone marrow mesenchymal stem cells into osteoblasts via miR-320c by targeting Runx2.

Bone marrow mesenchymal stem cells (BMSCs) are a potential source of osteoblasts and have been widely used in clinical therapies due to their pluripotency. Recent publications have found that resveratrol (RSVL) played a crucial role in the proliferation and differentiation of BMSCs; however, the underlying molecular mechanism of RSVL-induced BMSCs osteogenic differentiation needs to be fully elucidated. The objective of this study was to explore functions of miRNAs in the RSVL-treated BMSCs and its effects on the differentiation potentials of BMSCs. The findings demonstrated that RSVL enhanced the osteogenesis and suppressed the adipogenesis of BMSCs in a dose-dependent manner. Besides, a novel regulatory axis containing miR-320c, and its target Runx2 was found during the differentiation process of BMSCs under RSVL treatment. Increase of miR-320c reduced the osteogenic potential of BMSCs, while knockdown of miR-320c played a positive role in the osteogenesis of BMSCs. In contrast, overexpression of miR-320c accelerated the adipogenic differentiation, while knockdown of miR-320c restrained the adipogenic differentiation of BMSCs. The results confirmed that Runx2 might be the direct target of miR-320c in RSVL-promoted osteogenic differentiation of BMSCs. This study revealed that RSVL might be used for the treatment of bone loss related diseases and miR-320c could be regarded as a novel and potential target to regulate the biological functions of BMSCs.

Metabolic targeting of HIF-1α potentiates the therapeutic efficacy of oxaliplatin in colorectal cancer.

Drug resistance is a major problem limiting the efficacy of chemotherapy in cancer treatment, and the hypoxia-induced stabilization of HIF-1α plays a role in this process. HIF-1α overexpression has been observed in a variety of human cancers, including colorectal cancer (CRC). Therefore, targeting HIF-1α is a promising strategy for overcoming chemoresistance to enhance the efficacy of chemotherapies in CRC. Here, we show that DNMT inhibitors can induce HIF-1α degradation to overcome oxaliplatin resistance and enhance anti-CRC therapy. We found that a low-toxicity DNMT inhibitor, zebularine, could downregulate HIF-1α expression and overcome hypoxia-induced oxaliplatin resistance in HCT116 cells and showed efficacy in HCT116 xenograft models and AOM/DSS-induced CRC mouse models. Zebularine could induce the degradation of HIF-1α protein through hydroxylation. LC-MS analysis showed a decrease in succinate in various CRC cells under hypoxia and in colon tissues of AOM/DSS-induced CRC mice. The decrease was reversed by zebularine. Tumor angiogenesis was also reduced by zebularine. Furthermore, zebularine potentiated the anticancer effect of oxaliplatin in AOM/DSS-induced CRC models. This finding provides a new strategy in which an increase in HIF-1α hydroxylation could overcome oxaliplatin resistance to enhance anti-CRC therapy.

Assessments of bone morphogenetic proteins 2 and 7 in treating nonunion / 中国组织工程研究

BACKGROUND: Autologous bone transplantation combined with strong fixation is considered as the gold standard for the treatment of nonunion. At present, there are many cases in which bone nonunion is treated with bone morphogenetic proteins 2 and 7. OBJECTIVE: To describe the osteogenic pathway of bone morphogenetic proteins at the gene level, summarize the clinical cases of nonunion treated with bone morphogenetic protein, and compare the therapeutic effects of bone morphogenetic proteins 2 and 7 on nonunion, followed by evaluation and analysis. METHODS: The first author used a computer to search the full-text database of Chinese journals, WanFang database and PubMed database. The key words were “BMP, nonunion, pathway, external fixator, ORIF, bone graft, infected nonunion, bone defect, osteoblast, osteoporosis " and 59 articles were finally included in the result analysis. RESULTS AND CONCLUSION: Literature review indicates that the gene-level pathway of bone morphogenetic protein can provide therapeutic ideas in clinical practice. In the treatment of bone nonunion, bone morphogenetic proteins 2 and 7 are effective, but there are yet no specifications and standards for the use of bone morphogenetic proteins, such as usage amount and indications. From the overall treatment effect and the treatment effect on infected bone nonunion, we compare the use of bone morphogenetic proteins 2 and 7. The effect of bone morphogenetic protein 2 is better than that of bone morphogenetic protein 7, especially in the treatment of infected nonunion.

[Prevalence and surgical status of cataract among adults aged 50 years or above in rural Jiangsu Province].

OBJECTIVE: To survey the prevalence, operative status, surgical coverage rate and social burden rate of cataract blindness among older adults aged 50 years or above in 2 typical counties (district) of Jiangsu Province, China in 2010. METHODS: Cluster sampling was used in randomly selected 12 867 individuals aged 50 years or above in 58 clusters in Funing County of Northern Jiangsu and Binhu District of Southern Jiangsu. Among them, 12 053 individuals received visual acuity and eye examinations (response rate 93.8%). Lens and cataract operative status were evaluated by slit-lamp biomicroscope. Data bank was established by Epidata3.0 Software. Statistical analyses were performed with Stata/SE Statistical Software, version 10.0. Confidence intervals and P values (significant at P < 0.05) for prevalence of cataract, surgical coverage rate of cataract, social burden rate and surgical outcomes of cataract blindness were calculated with adjustment for clustering effects and stratification associated with the sampling design. RESULTS: Among 12 503 individuals, there were 2208 cases of cataract with a prevalence of 18.3%. The prevalence of cataract was higher in the aged, female and lower-income persons (P < 0.05). Among 2208 cataract patients, cataract surgery was performed in 263 cases (11.9%). The surgical coverage rate of cataract was 59.7% and the social burden rate of cataract blindness 1.93%. The social burden rate of cataract blindness was higher in the aged persons (P < 0.01). In 357 eyes with cataract surgery, the rate of intraocular lens implantation was 85.7%. At Binhu, 71.0% of eyes with cataract surgery underwent phacoemulsification. At Funing, 73.6% of eyes underwent modern extra-capsular surgery respectively. Post-operative presenting and best corrected visual acuity over 0.7 was 11.2% and 19.6% of operated eyes respectively. The main causes of post-operative eyes with worse visual acuity (< 0.3) were post-capsular opacity and retinal disorders. CONCLUSION: Cataract is the most common and important eye disease that may lead into blindness and severe visual impairment among older adults aged 50 years or above. The coverage rate of cataract surgery is higher in Jiangsu province than in other provinces. The visual outcomes of surgery is less than ideal. An important task in blindness prevention of Jiangsu province still is the elimination of cataract blindness and the improvement of visual outcomes for cataract surgery in the future.

Quantitative assessment of DNA damage directly in age-related cataract patients / 中华实验眼科杂志

Background Age-related cataract is one of the common causes of blindness.Although the pathophysiology of age-related cataract is far from clearly understood,it is well accepted that DNA damage plays an important role in the disease pathogenesis.Objective The purpose of this study was to quantitatively evaluate the DNA damage in peripheral lymphocytes of age-related cataract.Methods A cross-sectional study was carried out.This study complied Declaration of Helsinki and approved by Ethic Committee of Affiliated Hospital of Nantong University.Written informed consent was obtained from each subject.Two hundred and eleven patients with agerelated cataract and 147 normal subjects were enrolled from a “ Jiangsu Eye Study:Funing 2011 Eye Disease Epidemic Survey”.All the subjects aged from 50 through 80 years with matched age and gender between the two groups.The percentage of tail DNA and Olive tail moment (OTM) were detected by comet assay to assess the extent of DNA damage in peripheral lymphocytes.Statistical analyses were performed with SPSS 17.0 software,and the differences of the percentage of tail DNA and OTM were compared between the age-related cataract group and normal control group by independent sample t test as well as among the 50-59 years group,60-69 years group and ≥70 years group by one-way analysis of variance.Results Comet assay showed a round lymph cell with the clear border in the normal group;while in the age-related cataract group,the cell was bigger with a comet-like tail.The percentage of tail DNA and OTM in peripheral lymphocytes were (21.75 ± 3.51) ％ and 6.54 ± 1.65 in the age-related cataract group,and those in the normal control group were (9.31 ±3.60)％ and 2.18 ± 1.10,respectively,with significant differences between them (t =32.67,P =0.00 ; t =28.02,P =O.00).In the 50-59 years subgroup of the age-related cataract group,the percentage of tail DNA and OTM in peripheral lymphocytes were (20.04±2.86) ％ and 5.92± 1.14,and in the 60-69 years subgroup of the age-related cataract group,the percentage of tail DNA and OTM in peripheral lymphocytes were (20.77 ±2.93) ％ and 6.13 ± 1.14,which were significantly reduced in comparison with (22.79 ± 3.67)％ and 6.95±1.91 of the ≥70years subgroup(TailDNA％:q=2.75,P=0.00; q=2.02,P=0.00;OTM:q=1.03,P =0.02 ; q =0.82,P =0.00).Conclusions The pathogenesis and development of age-related cataract probably is associated with DNA damage.