Circular RNA_0000326 accelerates breast cancer development via modulation of the miR-9-3p/YAP1 axis.

Circular RNA (circ)_0000326 has been reported in bladder cancer and cervical cancer and is concerned to be involved with the development of cancerous cells. Whereas, there have been no reports concentrating on the influences of circ_0000326 in breast cancer (BC). Therefore, the latent modulatory mechanisms of circ_0000326 in BC are researched. circ_0000326 expression in BC tissues and correlative cells was evaluated via RT-qPCR, and the relevance between circ_0000326 expression and overall survival and the clinicopathological feature was also investigated. After a series of transfection, the effects of circ_0000326, microRNA-9-3p (miR-9-3p), and Yes-associated protein 1 (YAP1) in BC cell growth, invasion, and stemness were studied by CCK-8, flow cytometry, Transwell, and sphere-forming assays. The binding sites and correlation of circ_0000326, miR-9-3p, and YAP1 were certified via starBase website, luciferase reporter assay, and Pearson's χ2 test. The in vivo experiment was evaluated by establishing a subcutaneous tumorigenesis model. High-expressed circ_0000326 in BC tissues and cells was discovered, which was connected with an undesirable prognosis. Silencing of circ_0000326 visibly inhibited MCF-7 and BT549 cell growth, invasion, stemness, meanwhile declining the protein levels of SRY-related high-mobility group box gene 2 (SOX2) and octamer binding transcription factor 4 (OCT4). miR-9-3p was a sponger of circ_0000326, which was negatively regulated by circ_0000326. Moreover, YAP1 was confirmed as a target gene of miR-9-3p. circ_0000326 affected BC cell behaviors via mediating miR-9-3p and YAP1. Furthermore, circ_0000326 silencing prohibited tumor growth of BC in vivo. The research uncovered that circ_0000326 facilitated BC development via mediating the miR-9-3p/YAP1 axis.

MicroRNA-99a-5p suppresses breast cancer progression and cell-cycle pathway through downregulating CDC25A.

In this study, we aimed to explore the association between miR-99a-5p and CDC25A in breast cancer and the regulatory mechanisms of miR-99a-5p on breast cancer. The expressions of messenger RNA and microRNAs in breast cancer tissues and adjacent tissues were analyzed by the Cancer Genome Atlas microarray analysis. Quantitative real-time polymerase chain reaction was conducted to find out the expression levels of miR-99a-5p and CDC25A. The expression levels of proteins (CDC25A, ki67, cyclin D1, p21, BAX, BCL-2, BCL-XL, MMP2, and MMP9) were determined by Western blot analysis. The relationship between miR-99a-5p and CDC25A was predicted and verified by bioinformatics analysis and dual luciferase assay. After transfection, cell proliferation, invasion, and apoptosis of breast cancer tissues were, respectively, observed by cell counting kit-8 assay, transwell assay, and flow cytometry (FCM). Furthermore, the relationship among miR-99a-5p, CDC25A, and cell-cycle progression was determined by FCM assay. The nude mouse transplantation tumor experiment was performed to verify the influence of miR-99a-5p on breast cancer cell in vivo. The expression of miR-99a-5p in breast cancer tissues and cells was significantly downregulated, whereas CDC25A expression was upregulated. MiR-99a-5p targeted CDC25A and suppressed its expression in breast cancer cells. Overexpression of miR-99a-5p and decreased expression of CDC25A could suppress breast cancer cell proliferation and invasion and facilitate apoptosis. Cell-cycle progression was significantly activated by downregulated miR-99a-5p and upregulated CDC25A. Moreover, miR-99a-5p overexpression repressed the expressions of CDC25A, marker ki67, and Cyclin D1 proteins, whereas it upregulated the expression of p21 protein. MicroRNA-99a-5p suppresses breast cancer progression and cell-cycle pathway through downregulating CDC25A.

RNF43 Inhibits Cancer Cell Proliferation and Could be a Potential Prognostic Factor for Human Gastric Carcinoma.

BACKGROUND/AIMS: RNF43 is a member of transmembrane E3 ubiquitin ligases and plays important roles in tumor formation progression. In current study, we aimed to explore RNF43 expression and analyze its role in gastric carcinoma. METHODS AND RESULTS: The level of RNF43 was detected in 77 cases of gastric carcinoma and matched normal tissues by real-time PCR, western blotting and immunohistochemistry. We found that the expression of RNF43 was significantly down-regulated in the gastric carcinoma tissues compared to the normal mucosae (all P<0.001). In addition, RNF43 was significantly correlated with histological differentiation (P = 0.001), T-stage cancer (P<0.001), depth of invasion (P<0.001), metastasis of regional lymph nodes (P<0.001), pTNM stage (P<0.001) and survival (P = 0.021). We further explored the biological functions of RNF43 in gastric carcinoma cell lines. Both gain- and loss-function assays show that RNF43 could suppress cell proliferation while promotes cell apoptosis. Further, we found that RNF43 was positively correlated with p53 and cleaved-caspase3 and negatively correlated with Ki67 and Lgr5. CONCOLUSION: In conclusion, RNF43 might act as a tumor suppressor in gastric carcinoma and might be a potential indicator for the clinical assessment of gastric cancer prognosis.

Accuracy of 16/18G core needle biopsy for ultrasound-visible breast lesions.

BACKGROUND: To assess the accuracy of ultrasound-guided 16G or 18G core needle biopsy (CNB) for ultrasound-visible breast lesions, and to analyze the effects of lesion features. METHODS: Between July 2005 and July 2012, 4,453 ultrasound-detected breast lesions underwent ultrasound-guided CNB and were retrospectively reviewed. Surgical excision was performed for 955 lesions (566 with 16G CNB and 389 with 18G CNB) which constitute the basis of the study. Histological findings were compared between the ultrasound-guided CNB and the surgical excision to determine sensitivity, false-negative rate, agreement rate, and underestimation rate, according to different lesion features. RESULTS: Final pathological results were malignant in 84.1% (invasive carcinoma, ductal carcinoma in situ, lymphoma, and metastases), high-risk in 8.4% (atypical lesions, papillary lesions, and phyllodes tumors), and benign in 7.5%. False-negative rates were 1.4% for 16G and 18G CNB. Agreement rates between histological findings of CNB and surgery were 92.4% for 16G and 92.8% for 18G CNB. Overall underestimate rates (high-risk CNB becoming malignant on surgery and ductal carcinoma in situ becoming invasive carcinoma) were 47.4% for 16G and 48.9% for 18G CNB. Agreements were better for mass lesions (16G: 92.7%; 18G: 93.7%) than for non-mass lesions (16G, 85.7%; 18G, 78.3%) (P <0.01). For mass lesions with a diameter ≤10 mm, the agreement rates (16G, 83.3%; 18G, 86.7%) were lower (P <0.01). CONCLUSIONS: Ultrasound-guided 16G and 18G CNB are accurate for evaluating ultrasound-visible breast mass lesions with a diameter >10 mm.

The molecular mechanism and potential role of heat shock-induced p53 protein accumulation.

Workers who are exposed to extreme heat or work in hot environments may be at risk of heat stress. Exposure to extreme heat can result in occupational illnesses and injuries. On the other hand, local and regional heat therapy has been used for the treatment of some cancers, such as liver cancer, lung cancer, and kidney cancer. Although heat stress has been shown to induce the accumulation of p53 protein, a key regulator of cell cycle, apoptosis, DNA repair, and autophagy, how it regulates p53 protein accumulation and what the p53 targets are remain unclear. Here, we show that, among various genotoxic stresses, including ionizing radiation (IR) and ultraviolet (UV) radiation, heat stress contributes significantly to increase p53 protein levels in normal liver cells and liver cancer cells. Heat stress did not increase p53 mRNA expression as well as p53 promoter activity. However, heat stress enhanced the half-life of p53 protein. Moreover, heat stress increased the expression of puma and light chain 3 (LC-3), which are associated with the apoptotic and autophagic function of p53, respectively, whereas it did not change the expression of the cell cycle regulators p21, 14-3-3δ, and GADD45α, suggesting that heat-triggered alteration of p53 selectively modulates the downstream targets of p53. Our study provides a novel mechanism by which heat shock stimulates p53 protein accumulation, which is different from common DNA damages, such as IR and UV, and also provides new molecular basis for heat injuries or heat therapy.

Genome-wide analysis of NBS-LRR genes revealed contribution of disease resistance from Saccharum spontaneum to modern sugarcane cultivar.

Introduction: During plant evolution, nucleotide-binding sites (NBS) and leucine-rich repeat (LRR) genes have made significant contributions to plant disease resistance. With many high-quality plant genomes sequenced, identification and comprehensive analyses of NBS-LRR genes at whole genome level are of great importance to understand and utilize them. Methods: In this study, we identified the NBS-LRR genes of 23 representative species at whole genome level, and researches on NBS-LRR genes of four monocotyledonous grass species, Saccharum spontaneum, Saccharum officinarum, Sorghum bicolor and Miscanthus sinensis, were focused. Results and discussion: We found that whole genome duplication, gene expansion, and allele loss could be factors affecting the number of NBS-LRR genes in the species, and whole genome duplication is likely to be the main cause of the number of NBS-LRR genes in sugarcane. Meanwhile, we also found a progressive trend of positive selection on NBS-LRR genes. These studies further elucidated the evolutionary pattern of NBS-LRR genes in plants. Transcriptome data from multiple sugarcane diseases revealed that more differentially expressed NBS-LRR genes were derived from S. spontaneum than from S. officinarum in modern sugarcane cultivars, and the proportion was significantly higher than the expected. This finding reveals that S. spontaneum has a greater contribution to disease resistance for modern sugarcane cultivars. In addition, we observed allelespecific expression of seven NBS-LRR genes under leaf scald, and 125 NBS-LRR genes responding to multiple diseases were identified. Finally, we built a plant NBS-LRR gene database to facilitate subsequent analysis and use of NBSLRR genes obtained here. In conclusion, this study complemented and completed the research of plant NBS-LRR genes, and discussed how NBS-LRR genes responding to sugarcane diseases, which provided a guide and genetic resources for further research and utilization of NBS-LRR genes.

HFO Detection in Epilepsy: A Stacked Denoising Autoencoder and Sample Weight Adjusting Factors-Based Method.

High-frequency oscillations (HFOs) recorded by the intracranial electroencephalography (iEEG) are the promising biomarkers of epileptogenic zones. Accurate detection of HFOs is the key to pre-operative assessment for epilepsy. Due to the subjective bias caused by manual features and the class imbalance between HFOs and false HFOs, it is difficult to obtain satisfactory detection performance by the existing methods. To solve these problems, we put forward a novel method to accurately detect HFOs based on the stacked denoising autoencoder (SDAE) and the ensemble classifier with sample weight adjusting factors. First, the adjustable threshold of Hilbert envelopes is proposed to isolate the events of interest (EoIs) from background activities. Then, the SDAE network is utilized to automatically extract features of EoIs in the time-frequency domain. Finally, the AdaBoost-based support vector machine ensemble classifier with sample weight adjusting factors is devised to separate HFOs from EoIs by using the extracted features. These adjusting factors are used to solve the class imbalance problem by adjusting sample weights when learning the base classifiers. Our HFO detection method is evaluated by using clinical iEEG data recorded from 20 patients with medically refractory epilepsy. The experimental results show that our detection method outperforms some existing methods in terms of sensitivity and false discovery rate. In addition, the HFOs detected by our method are effective for localizing seizure onset zones.

LKB1 inhibits the proliferation of gastric cancer cells by suppressing the nuclear translocation of Yap and ß-catenin.

Liver kinase B1 (LKB1) is known to suppress the proliferation, energy metabolism and mesenchymal transition of various cancer cells, and is involved in the regulation of Hippo-Yes-associated protein (Yap) and the Wnt/ß-catenin signaling pathways. However, the role of LKB1 in gastric cancer (GC) was not fully understood. Thus, in the present study, we studied LKB1 and found that protein expression (0.37±0.061 vs. 0.59±0.108, P=0.006) and the protein ratio of p-Yap/Yap (0.179±0.085 vs. 0.8±0.126, P=0.001) were reduced in 54 gastric adenocarcinoma (GAC) tissues compared with the matched adjacent non-cancerous tissues, using western blotting and RT-qPCR assays. LKB1 expression was also observed decreased in 109 GAC tissues compared with 54 adjacent non-cancerous tissues (χ2=4.678, P=0.0306), and negatively correlated with the nuclear expression of Yap (r=-0.6997) and ß-catenin (r=-0.3510), using immunohistochemical analysis. In GC patients, LKB1 expression was negatively associated with tumor size, tumor infiltration, lymph node metastasis and the TNM stage. LKB1 expression was determined to be positively correlated with longer overall survival of GC patients using Kaplan-Meier analysis (P=0.001). Subsequently, LKB1 expression in human GAC AGS cells was enhanced with a full­length LKB1 transfection. In vitro and in vivo proliferation was inhibited in LKB1-overexpressing GC cells compared with the control cells. Yap and ß-catenin expression were assessed by western blotting and RT-qPCR, and were found to be increased in the cytoplasm but decreased in the nucleus in LKB1-overexpressing GC cells compared with the control cells. The increase in cytoplasmic ß-catenin was reversed by the silencing of LKB1 or Yap with shRNAs in LKB1-overexpressing GC cells. Moreover, Yap and ß-catenin mRNA were barely altered by LKB1 overexpression. Thus, we concluded that LKB1 expression was reduced in GAC tissues but that it correlated positively with better prognosis for GC patients. LKB1 inhibits the proliferation of GC cells by suppressing the nuclear translocation of Yap and ß-catenin.

ZnRF3 Induces Apoptosis of Gastric Cancer Cells by Antagonizing Wnt and Hedgehog Signaling.

A large proportion of malignant cancers of the stomach are gastric adenocarcinoma type. In spite of many studies, the molecular basis for this cancer is still unclear. Deregulated cell proliferative signaling via Wnt/ß-catenin and Hedgehog pathways is considered important in the pathogenesis of many cancers including the gastric cancer. Recent studies identified ZnRF3 protein, which is a E3-ubiquitin ligase and which is either deleted or mutated in cancers, to inhibit Wnt signaling. However, the significance of ZnRF3 in the control of gastric cancer and whether it also regulates Hedgehog signaling pathway, is not known. In the present study, we assessed the expression of ZnRF3 in gastric tumors and paracancerous tissues from 58 patients (44 male and 14 female) of different ages and related this to patient survival. We observed a clear relationship between ZnRF3 expression in paracancerous tissue and tumor size. Also, ZnRF3 expression was much higher in tumors from aged patients. Male patients showed higher mortality than the females. Mechanistic studies using normal gastric cells (GES1) and gastric cancer cells (MGC-803) infected with either AdZnRF3 or AdGFP viral vectors, revealed that ZnRF3 overexpression causes significantly more apoptosis and lowered proliferation of cancer cells. ZnRF3 overexpression led to greatly reduced levels of Lgr5, a component of Wnt signaling and also Gli1, a component of Hedgehog signaling. Thus, ZnRF3 negatively influences both the Wnt and Hedgehog proliferative pathways, and probably this way it negatively regulates cancer progression. These results suggest the importance of normal ZnRF3 function in checking the progression of cancer cell growth and indicate that a lack of this protein can lead to poorer clinical outcomes for gastric cancer patients.