Generation of DNA Aptamers with Functional Activity in Mammalian Cells by Mimicking Retroviruses.

DNA aptamers are single-stranded DNA oligonucleotide sequences that bind to specific targets with high affinity. Currently, DNA aptamers can be produced only by in vitro synthesis. It is difficult for DNA aptamers to have a sustained impact on intracellular protein activity, which limits their clinical application. In this study, we developed a DNA aptamer expression system to generate DNA aptamers with functional activity in mammalian cells by mimicking retroviruses. Using this system, DNA aptamers targeting intracellular Ras (Ra1) and membrane-bound CD71 (XQ2) were successfully generated in cells. In particular, the expressed Ra1 not only specifically bound to the intracellular Ras protein but also inhibited the phosphorylation of downstream ERK1/2 and AKT. Furthermore, by inserting the DNA aptamer expression system for Ra1 into a lentivirus vector, the system can be delivered into cells and stably produce Ra1 over time, resulting in the inhibition of lung cancer cell proliferation. Therefore, our study provides a novel strategy for the intracellular generation of DNA aptamers with functional activity and opens a new avenue for the clinical application of intracellular DNA aptamers in disease treatment.

Associations between TNFSF4 gene polymorphisms (rs2205960 G > A, rs704840 T > G and rs844648 G > A) and susceptibility to autoimmune diseases in Asians: a meta-analysis.

BACKGROUND: Tumor necrosis factor superfamily member 4 (TNFSF4) has significant role in modulating autoimmune diseases (ADs) and single nucleotide polymorphism (SNP) is also related with the susceptibility to some diseases. So a meta-analysis aimed at systematically assessing the associations between TNFSF4 polymorphisms (rs2205960 G > A, rs704840 T > G and rs844648 G > A) and ADs risk was performed in Asians. METHODS: Total 14 eligible articles published before March 2019 involving 35 studies, of which 21 studies (16,109 cases and 26,378 controls) for rs2205960 G > A, 8 studies (2,424 cases and 3,692 controls) for rs704840 T > G, and 6 studies (3,839 cases and 5,867 controls) for rs844648 G > A were included. Effects of the three respective polymorphisms on the susceptibility to ADs were estimated by pooling the odds ratios (ORs) with their corresponding 95% confidence interval (95% CI) in allelic, dominant, recessive, heterozygous and homozygous models. RESULTS: The overall analysis revealed that all the rs2205960 G > A, rs704840 T > G and rs844648 G > A polymorphisms could increase the risk of ADs in allelic, dominant, recessive, heterozygous and homozygous models. Furthermore, subgroup analysis showed that both rs2205960 G > A and rs704840 T > G were significantly associated with the susceptibility to systemic lupus erythematosus (SLE). What's more, statistically significant association between rs2205960 G > A polymorphism and primary Sjögren's syndrome (pSS) susceptibility was also observed in allelic, dominant and heterozygous models. CONCLUSIONS: This current meta-analysis suggested that all of the three TNFSF4 polymorphisms may be associated with ADs susceptibility in Asians.

Prevalence and characteristics of chronic Pain in the Chinese community-dwelling elderly: a cross-sectional study.

BACKGROUND: Chronic pain adversely affects health and daily life in the elderly. Gaining insight into chronic pain that affects the community-dwelling elderly is crucial for pain management in China, which possesses the largest elderly population in the world. METHODS: This is a cross-sectional design study that followed the STROBE Guideline. A randomized cluster sampling method was used to recruit participants in the Sichuan Province from Dec 2018 to May 2019. In addition, face-to-face interviews were conducted to collect socio-demographic data, characteristics and health-seeking behaviors of chronic pain through a self-designed questionnaire. RESULTS: A total of 1381 older adults participated in this study. Among these participants, 791 (57.3%) had chronic pain. Here, prevalence and pain intensity were both found to increase from the 60-69 group to the 70-79 group, which then decreased in the ≥80 group with no significant differences in sex (p > 0.05). The most common pain locations were observed in the legs/feet (53.5%), head (23.6) and abdomen/pelvis (21.1%). Among the elderly suffering from chronic pain, 29.4% sought medical help, 59.2% received medication and 59.7% adopted non-drug therapy. CONCLUSION: Chronic pain is a common health concern in the Chinese community-dwelling elderly, which possesses different characteristics than other countries' populations. Therefore, easier access to medication assistance and provision of scientific guidance for non-drug therapy may serve as satisfactory approaches in improving pain management.

Circadian protein BMAL1 promotes breast cancer cell invasion and metastasis by up-regulating matrix metalloproteinase9 expression.

BACKGROUND: Metastasis is an important factor in the poor prognosis of breast cancer. As an important core clock protein, brain and muscle arnt-like 1 (BMAL1) is closely related to tumorigenesis. However, the molecular mechanisms that mediate the role of BMAL1 in invasion and metastasis remain largely unknown. In this study, we investigated the BMAL1 may take a crucial effect in the progression of breast cancer cells. METHODS: BMAL1 and MMP9 expression was measured in breast cell lines. Transwell and scratch wound-healing assays were used to detect the movement of cells and MTT assays and clonal formation assays were used to assess cells' proliferation. The effects of BMAL1 on the MMP9/NF-κB pathway were examined by western blotting, co-immunoprecipitation and mammalian two-hybrid. RESULTS: In our study, it showed that cell migration and invasion were significantly enhanced when overexpressed BMAL1. Functionally, overexpression BMAL1 significantly increased the mRNA and protein level of matrix metalloproteinase9 (MMP9) and improved the activity of MMP9. Moreover, BMAL1 activated the NF-κB signaling pathway by increasing the phosphorylation of IκB and promoted human MMP9 promoter activity by interacting with NF-kB p65, leading to increased expression of MMP9. When overexpressed BMAL1, CBP (CREB binding protein) was recruited to enhance the activity of p65 and further activate the NF-κB signaling pathway to regulate the expression of its downstream target genes, including MMP9, TNFα, uPA and IL8, and then promote the invasion and metastasis of breast cancer cells. CONCLUSIONS: This study confirmed a new mechanism by which BMAL1 up-regulated MMP9 expression to increase breast cancer metastasis, to provide research support for the prevention and treatment of breast cancer.

Expression of Adiponectin Receptor-1 and Prognosis of Epithelial Ovarian Cancer Patients.

BACKGROUND Adiponectin receptor-1 (AdipoR1) has been reported to be associated with the risk of obesity-associated malignancies, including epithelial ovarian cancer (EOC). The aim of this study was to determine if AdipoR1 could serve as a prognosis indicator for patients with EOC. MATERIAL AND METHODS In this study, expression of AdipoR1 in 73 EOC patients consecutively admitted to our hospital was detected by immunohistochemical staining. Univariate and multivariate analyses were performed to assess the relationship between AdipoR1 expression level and progression-free survival (PFS) and overall survival (OS) rates in patients. RESULTS A relatively lower expression of AdipoR1 in the cancerous tissues was detected compared to normal ovarian tissues, but the difference was not significant (p>0.05). AdipoR1 expression level in EOC patients was negatively correlated with advanced FIGO stages in patients and tumor differentiation, but had no correlation with pathological types, presenting of ascites, shorter platinum-free interval (PFI), diabetes, preoperative and postoperative body mass index (BMI), or platelet counts (p>0.05). Moreover, patients with AdipoR1 expression had a significantly longer PFS and OS compared to the negative expression group (p<0.001). CONCLUSIONS Our findings suggest that AdipoR1 expression level in cancerous tissues might serve as an independent prognostic indicator in EOC patients and is associated with longer PFS and OS.

The defect feature extraction of ultrasonic phased array detection based on adaptive region growth.

An ultrasonic phased array defect extraction method based on adaptive region growth is proposed, aiming at problems such as difficulty in defect identification and extraction caused by noise interference and complex structure of the detected object during ultrasonic phased array detection. First, bilateral filtering and grayscale processing techniques are employed for the purpose of noise reduction and initial data processing. Following this, the maximum sound pressure within the designated focusing region serves as the seed point. An adaptive region iteration method is subsequently employed to execute automatic threshold capture and region growth. In addition, mathematical morphology is applied to extract the processed defect features. In the final stage, two sets of B-scan images depicting hole defects of varying sizes are utilized for experimental validation of the proposed algorithm's effectiveness and applicability. The defect features extracted through this algorithm are then compared and analyzed alongside the histogram threshold method, Otsu method, K-means clustering algorithm, and a modified iterative method. The results reveal that the margin of error between the measured results and the actual defect sizes is less than 13%, representing a significant enhancement in the precision of defect feature extraction. Consequently, this method establishes a dependable foundation of data for subsequent tasks, such as defect localization and quantitative and qualitative analysis.

Linear and high-molecular-weight poly-porphyrins for efficient photodynamic therapy.

Photodynamic therapy (PDT) holds great potential in cancer treatment due to the advantages of non-invasiveness, negligible side-effect, and high spatiotemporal selectivity. Porphyrin is the most widely used photosensitizer in clinical treatment. However, its PDT efficacy is always limited by the undesired aggregation caused quenching (ACQ) effect originating from the planar and rigid structure. In this work, a linear polymeric porphyrin with "structure defects" was developed to overcome the ACQ effect for most of the photosensitizers with conjugated macrocycles. Compared to porphyrin monomers, poly-porphyrins could improve singlet oxygen generation ability, and the singlet oxygen quantum yield enhanced with increasing molecular weight of poly-porphyrins. To achieve efficient in vivo PDT, PEG and acetazolamide were conjugated to the optimized poly-porphyrins to afford pP-PEG-AZ nanoparticles (pP-PEG-AZ NPs) with excellent stability, efficient in vitro intracellular internalization, negligible dark-toxicity, notable photo-toxicity, and in vivo anti-cancer efficacy based on combined PDT and anti-angiogenesis therapy.

Acetylation of ELF5 suppresses breast cancer progression by promoting its degradation and targeting CCND1.

E74-like ETS transcription factor 5 (ELF5) is involved in a wide spectrum of biological processes, e.g., mammogenesis and tumor progression. We have identified a list of p300-interacting proteins in human breast cancer cells. Among these, ELF5 was found to interact with p300 via acetylation, and the potential acetylation sites were identified as K130, K134, K143, K197, K228, and K245. Furthermore, an ELF5-specific deacetylase, SIRT6, was also identified. Acetylation of ELF5 promoted its ubiquitination and degradation, but was also essential for its antiproliferative effect against breast cancer, as overexpression of wild-type ELF5 and sustained acetylation-mimicking ELF5 mutant could inhibit the expression of its target gene CCND1. Taken together, the results demonstrated a novel regulation of ELF5 as well as shedding light on its important role in modulation of breast cancer progression.

α-catenin SUMOylation increases IκBα stability and inhibits breast cancer progression.

α-catenin has been demonstrated to suppress several different types of cancers. Here we demonstrate that α-catenin is modified by SUMO protein, which covalently binds α-catenin at the carboxy terminus at lysine 870. Substitution of lysine 870 with arginine completely abolishes α-catenin SUMOylation. This modification can be removed by SENP1. However, α-catenin SUMOylation does not affect its stability and subcellular localization. In addition, we observed that the SUMOylation-deficient α-catenin mutant has a reduced interaction with IκBα which prevents subsequent ubiquitination of IκBα, and therefore a reduced suppression of expression of the NF-κB target genes TNF-α, IL-8, VEGF, and uPA. In addition, the α-catenin SUMOylation mutant shows impaired suppression of tumor growth. These results demonstrate that SUMOylation at lysine 870 of α-catenin plays a key role in the suppression of the NF-κB pathway, which inhibits breast cancer tumor growth and migration.

Checkpoint suppressor 1 suppresses transcriptional activity of ERα and breast cancer cell proliferation via deacetylase SIRT1.

Breast cancer is a highly heterogeneous carcinoma in women worldwide, but the underlying mechanisms that account for breast cancer initiation and development have not been fully established. Mounting evidence indicates that Checkpoint suppressor 1 (CHES1) is tightly associated with tumorigenesis and prognosis in many types of cancer. However, the definitive function of CHES1 in breast cancer remains to be explored. Here we showed that CHES1 had a physical interaction with estrogen receptor-α (ERα) and repressed the transactivation of ERα in breast cancer cells. Mechanistically, the interaction between CHES1 and ERα enhanced the recruitment of nicotinamide adenine dinucleotide (NAD+) deacetylase Sirtuin 1 (SIRT1), and it further induced SIRT1-mediated ERα deacetylation and repression on the promoter-binding enrichment of ERα. In addition, we also found that the expression of CHES1 was repressed by estrogen-ERα signaling and the expression level of CHES1 was significantly downregulated in ERα-positive breast cancer. The detailed mechanism was that ERα may directly bind to CHES1 potential promoter via recognizing the conserved estrogen response element (ERE) motif in response to estrogen stimulation. Functionally, CHES1 inhibited ERα-mediated proliferation and tumorigenesis of breast cancer cells in vivo and in vitro. Totally, these results identified a negative cross-regulatory loop between ERα and CHES1 that was required for growth of breast cancer cells, it might uncover novel insight into molecular mechanism of CHES1 involved in breast cancer and provide new avenues for molecular-targeted therapy in hormone-regulated breast cancer.

Krüppel-like factor 9 down-regulates matrix metalloproteinase 9 transcription and suppresses human breast cancer invasion.

Krüppel-like factor 9 (KLF9) plays critical roles in several types of tumor. However, the biological functions and the underlying mechanisms of KLF9 in breast cancer metastasis are still unknown. Here, we found the expression of KLF9 was significantly down-regulated in breast cancer and was inversely correlated with the expression of matrix metalloproteinase 9 (MMP9) in breast cancer patients. Functionally, KLF9 transcriptionally down-regulated MMP9 expression and inhibited the metastasis of breast cancer cells. Mechanistically, KLF9 repressed human MMP9 promoter activity by binding to the CACCC motif and interacting with NF-κB p50/p65, which interacted with the NF-κB response element of the MMP9 promoter, leading to decreased expression of MMP9. In the context of breast cancer, KLF9 promoted the accumulation of HDAC1, thereby decreasing the acetylation of the KLF9-binding site on the MMP9 promoter, and this might be the molecular basis of KLF9-mediated inhibition of MMP9 transcription. In addition to MMP9, KLF9 also down-regulated several other NF-κB targets, such as TNF-α, VEGFA and uPA in breast cancer cells. Taken together, these results uncovered a new mechanism by which KLF9 could down-regulate MMP9 expression to inhibit breast cancer metastasis.

U-box ubiquitin ligase PPIL2 suppresses breast cancer invasion and metastasis by altering cell morphology and promoting SNAI1 ubiquitination and degradation.

Metastasis is the leading cause of breast cancer fatalities. To develop new therapeutic strategies, the mechanisms underlying breast cancer invasion and metastasis need to be further investigated. Peptidylprolyl isomerase (cyclophilin)-like 2 (PPIL2) is a U-box-type E3 ubiquitin ligase belonging to the cyclophilin family. Proteins within this family are the major cytosolic binding proteins of the immunosuppressant drug cyclosporine A (CsA). Although PPIL2 has been reported to potentially be involved in cell migration, its role in breast cancer is still unclear. Herein, we demonstrate that PPIL2 suppressed metastasis in a breast cancer model by altering cell morphology and suppressing the epithelial-mesenchymal transition (EMT) process. Moreover, elevated PPIL2 inhibited EMT and breast cancer invasion by interacting with the classical EMT transcription factor, SNAI1, to enhance its ubiquitin-dependent degradation. Furthermore, PPIL2 protein level and stability was upregulated after CsA treatment, indicating that PPIL2 might be involved in CsA-mediated repression of EMT in breast cancer. Analysis of tissue samples taken from breast cancer patients showed a significant correlation between the expression of PPIL2 and the degree of cancer invasion and metastasis. In summary, these results would shed light on a potential clinical use of CsA in breast cancer patients.

SYNJ2BP promotes the degradation of PTEN through the lysosome-pathway and enhances breast tumor metastasis via PI3K/AKT/SNAI1 signaling.

SYNJ2BP plays an important role in breast cancer metastasis. However, the molecular mechanism associated with the function of SYNJ2BP in metastasis remains unclear. In this study, we investigated the role of SYNJ2BP in tumor metastasis and established the associated underlying mechanism. Over-expression of SYNJ2BP promoted both cell migration and invasion. In contrast, silencing SYNJ2BP caused the suppression of cell migration and invasion. SYNJ2BP increased the levels of phosphorylation for AKT and GSK3ß, which could be inhibited by the PI3K inhibitor, LY294002, and the GSK3ß inhibitor, LiCl, and regulated the accumulation of SNAI1 in the nucleus and the expression of the SNAI1 target gene, E-cadherin (EMT marker). It is known that the stability of PTEN is regulated by ubiquitination. However, in this study, we additionally demonstrated that SYNJ2BP mediated the degradation of PTEN protein by the lysosome-pathway and induced the activation of PI3K/AKT signaling by promoting the co-localization of PTEN with autophagy-lysosomes and the expression of LC3-II and p62. In vivo study, the overexpression of SYNJ2BP significantly increased the metastasis of 4T1 cells in BALB/c mice. In addition, SYNJ2BP was highly expressed in breast carcinoma (p = 0.0031), but not in normal breast tissue, while analysis of tissue samples taken from SNAI1-positive human breast cancers showed a significant correlation between the expression of SYNJ2BP and that of p-AKT (p < 0.005). Collectively, our data identified a tumor inducer, SYNJ2BP, which could activate the PI3K/AKT/GSK3ß/SNAI1 signaling pathway through the lysosome-mediated degradation of PTEN, and promote both EMT and tumor metastasis during the progression of breast cancer.

Inhibitory effect of Bailing capsule on hypoxia-induced proliferation of rat pulmonary arterial smooth muscle cells.

OBJECTIVES: To investigated the effects of Bailing capsule on hypoxia-induced proliferation of pulmonary arterial smooth muscle cells (PASMCs).   METHODS: This prospective study was performed at the Central Laboratory, Chengdu Medical College, Chengdu, China between April 2012 and November 2014. Ten healthy adult male Wistar rats were administrated with gastric perfusion of Bailing capsule to obtain serum containing the tested drugs. Proliferation of pulmonary arterial smooth muscle cells proliferation was measured using cell counting kit-8 assay. Production of reactive oxygen species (ROS) in rat PASMCs was determined through a fluorometric assay, whereas production of endothelin-1 (ET-1) was detected by ELISA and quantitative real-time PCR (qRT-PCR). Expression of proliferating cell nuclear antigen (PCNA), c-fos, and c-jun in PASMCs was also determined using immunohistochemistry staining and qRT-PCR.  RESULTS: We observed that the medicated serum obviously inhibited hypoxia-induced cell proliferation in a concentration-dependent manner. Moreover, the medicated serum significantly reduced hypoxia-induced production of ROS and ET-1, as well as expression of PCNA, c-fos, and c-jun, in PASMCs.  CONCLUSION: RESULTS demonstrated that Bailing capsule can inhibit hypoxia-induced PASMC proliferation possibly by suppressing ET-1 and ROS production and by inhibiting expression of PCNA, c-fos, and c-jun. These results suggest that Bailing possess antiproliferative property, which is probably one of the underlying mechanisms of Bailing capsule for the clinical treatment of chronic obstructive pulmonary disease.