Hydrogel binding sodium alginate based optical fiber surface plasmon resonance for calcium ion trace detection.

A plasmonic tilted fiber Bragg grating (TFBG)-based sensor for the detection of calcium ion (Ca2+) was proposed and demonstrated experimentally. Hydrogel material was synthesized by utilizing hydrogen bond recombination between cellulose nanocrystals (CNC) and polyvinyl alcohol (PVA). Sodium alginate (SA) was incorporated into this hydrogel material, resulting in a composite membrane with specific binding properties for Ca2+. The membrane was applied as a coating on the surface of a gold-coated TFBG. The CNC/PVA-SA modified gold on the TFBG surface enhanced the localized refractive index changes caused by variations of Ca2+ concentrations. The experimental results demonstrated an impressive limit of detection (LOD) of approximately 0.025 fM, which is five orders of magnitude better than the current LODs of similar Ca2+ sensors. And the proposed Ca2+ sensor exhibited a wide dynamic range of 10-16 M to 10-6 M.

An Integrated Systematic Analysis and the Clinical Significance of Hepcidin in Common Malignancies of the Male Genitourinary System.

Tumors of the male genitourinary system are of great concern to the health of men worldwide. Although emerging experiment-based evidence indicates an association between hepcidin and such cancers, an integrated analysis is still lacking. For this reason, in this study, we determined the underlying oncogenic functions of hepcidin in common male genitourinary system tumors, including bladder urothelial carcinoma (BLCA), kidney chromophobe (KICH), kidney renal clear cell carcinoma (KIRC), kidney renal papillary cell carcinoma (KIRP), prostate adenocarcinoma (PRAD), and testicular germ cell tumors (TGCT) according to the data from The Cancer Genome Atlas. We found that hepcidin was highly expressed in kidney and testicular cancers. Meanwhile, the expression level of hepcidin was distinctly associated with the prognosis and immune cell infiltration in male patients with certain genitourinary system cancers, especially in KIRC. Elevated hepcidin levels also present as a risk factor in male genitourinary system tumors. Moreover, enrichment analyses revealed that some of the principal associated signaling pathways involving hepcidin and its related genes are identified as tumorigenesis-related. Immunofluorescence staining confirmed the conclusion of our immune infiltration analysis in KIRC tissue. In this study, for the first time, we provided evidence for the oncogenic function of hepcidin in different types of male genitourinary system tumors.

Tumor-derived exosomes facilitate tumor cells escape from drug therapy in clear cell renal cell carcinoma.

BACKGROUND: Clear cell renal cell carcinoma (ccRCC) is one of the most prevalent cancers in renal cancer patients. Currently, mTOR and vascular endothelial growth factor (VEGF) inhibitors are the main targets of clinical drugs used to treat ccRCC. However, the major clinical challenge with these treatments is drug resistance. So far, the mechanisms of drug resistance in cancer are not fully understood. METHODS: We applied tumor-derived exosomes to treat renal cells to detect the survival rate after co-treated with anti-tumor drugs-TNFα, mammalian target of rapamycin (mTOR) inhibitor or STAT3 inhibitor. Meanwhile, we also detected the expression change in the protein level related to the proliferation and exosome secretion. RESULTS: Exosomes derived from renal carcinoma cells facilitate resistance in tumors cells when given drug therapy via the mTOR-ERK-STAT-NF-κB signaling pathway. CONCLUSIONS: Our results provide new insights on tumor cells resistance to drug therapies in general, and that exosomes could be the potential targets in treatment of ccRCC in future clinical therapy.

LncRNA MEG3 inhibits the progression of prostate cancer by facilitating H3K27 trimethylation of EN2 through binding to EZH2.

This study aims to study the effects of intra-nuclear lncRNA MEG3 on the progression of prostate cancer and the underlying mechanisms. Expressions of relative molecules were detected by Quantitative real time PCR (qRT-PCR) and western blot. Chromatin immunoprecipitation and RNA immunoprecipitation (RIP) assays were used to evaluate the interaction between intra-nuclear MEG3, histone methyltransferase EZH2 and Engrailed-2 (EN2). The impacts of MEG3 on the viability, proliferation and invasion of prostate cancer cells (PC3) were evaluated by methyl thiazolyl tetrazolium, colony formation and transwell assays, respectively. PC3 cells were transfected with MEG3 and transplanted into nude mice to analyse the effect of MEG3 on tumourigenesis of PC3 cells in vivo. EN2 expression was inversely proportional to MEG3 in the prostate cancer tissues and PC3 cells. RIP results showed that intra-nuclear MEG3 could bind to EZH2. Knockdown of MEG3 and/or EZH2 up-regulated EN2 expression and reduced the recruitment of EZH2 and H3K27me3 to EN2, while over-expressed MEG3 caused opposite effects. MEG3 over-expression suppressed cell viability, colony formation, cell invasion and migration of PC3 cells in vitro and inhibited tumourigenesis of PC3 cells in vivo, while EN2 over-expression diminished the effects. These findings indicated that MEG3 facilitated H3K27 trimethylation of EN2 via binding to EZH2, thus suppressed the development of prostate cancer.

Fat status detection and histotypes differentiation in solid renal masses using Dixon technique.

PURPOSE: To detect fat status and differentiate histotypes of renal masses by using Dixon technique. MATERIALS AND METHODS: This study included 134 solid renal masses. Signal intensity index (SII) and fat fraction (FF) in different histotypes were compared. RESULTS: Only angiomyolipoma (AML), clear cell renal cell carcinoma (RCC), and papillary RCC were confirmed to contain fat. The FF of 16.8% can effectively differentiate AML from clear cell RCC, so did the SII of 9.2% can differentiate clear cell RCC from non-clear cell RCC and rare benign histotypes. CONCLUSION: Dixon technique successfully evaluated the fat status and histotypes of renal masses.

Down-regulation of miR-605 promotes the proliferation and invasion of prostate cancer cells by up-regulating EN2.

AIMS: MicroRNA served as inhibitor for gene expression in various cancers. This study aimed to investigate the role of miR-605 and EN2 in prostate cancer (PCa). MATERIALS AND METHODS: In this research, the expression of miR-605 and EN2 protein in PCa tissues and cells were determined by qRT-PCR and western blot, respectively. The cell proliferation was measured by Cell Counting Kit-8 (CCK-8) and the tumor cell invasion assay was accomplished with transwell system. Flow cytometry was used to analyze the cell cycle. The endogenous expression of miR-605 and EN2 was modulated by recombinant plasmids and cell transfection. Dual luciferase reporter assay was performed to determine the interaction between miR-605 and EN2 in PCa cells. KEY FINDINGS: The expression of miR-605 was lower in PCa tissue and cells than that in normal tissues and cells, while the expression of EN2 was just the opposite. Down-regulation of the EN2 by siRNA inhibited the proliferation and invasion of PC3 cells, and the cell cycle was arrested in G0/G1 phase. EN2 regulated the expression of E-cadherin and Vimentin through Snail and EN2 regulated the cell cycle and cell proliferation via PI3K/AKT pathway. MiR-605 inhibited the proliferation and invasion of PCa cells through targeting EN2. SIGNIFICANCE: EN2 is negatively regulated by miR-605, and down-regulation of miR-605 promotes the proliferation and invasion of PCa cells by up-regulating EN2, which leads to PCa development and progression.

Transposable Element Bm1645 is a Source of BmAGO2-associated Small RNAs that affect its expression in Bombyx mori.

BACKGROUND: A transposable element (TE) is a DNA fragment that can change its position within a genome. Transposable elements play important roles in maintaining the stability and diversity of organisms by transposition. Recent studies have shown that approximately half of the genes in Bombyx mori are TEs. RESULTS: We systematically identified and analyzed the BmAGO2-associated TEs, which exceed 100 in the B. mori genome. Additionally, we also mapped the small RNAs associated with BmAGO2 in B.mori. The transposon Bm1645 is the most abundant TE associated with BmAGO2, and Bm1645-derived small RNAs represent a small RNA pool. We determined the expression patterns of several Bm1645-derived small RNAs by northern blotting, and the results showed there was differential expression of multiple small RNAs in normal and BmNPV-infected BmN cells and silkworms from various developmental stages. We confirmed that four TE-siRNAs could bind to BmAGO2 using EMSA and also validated the recognition sites of these four TE-siRNAs in Bm1645 by dual-luciferase reporter assays. Furthermore, qRT-PCR analysis revealed the overexpression of the four TE-siRNAs could downregulate the expression of Bm1645 in BmN cells, and the transcription of Bm1645 was upregulated by the downregulation of BmAGO2. CONCLUSIONS: Our results suggest Bm1645 functions as a source of small RNAs pool and this pool can produce many BmAGO2-associated small RNAs that regulate TE's expression.

Isolation and identification of cancer stem cells from PC3 human prostate carcinoma cell line.

OBJECTIVE: Morphological differences of PC3 clones were dynamically observed, and the expression of CD44 in different clones was detected to compare the tumorigenic ability of different clone cells in nude mice and identify the clones containing prostate cancer stem cells. MATERIALS AND METHODS: Clone formation assay was used for observing and classifying PC3 clones and calculating the cloning efficiency and the proportion of each clone. CD44 expression in different clones was detected by immunofluorescence technique. In addition, different morphologies of clones were isolated to measure the ability of self-renewing, and inoculated into nude mice to observe the tumorigenic ability. RESULTS: PC3 cells could form three morphologies of clones, namely holoclone, meroclone, and paraclone. The cloning efficiency was 10.23%±0.91%, and the proportion of the three clones was 11.7%, 50.0% and 38.3%, respectively. Immunofluorescence showed that the expression of CD44 in holoclone was significantly stronger than meroclone and paraclone. Holoclone had self-renewing ability and strong tumorigenic ability in nude mice. CONCLUSION: There are differences in morphologies and differentiation of PC3 clones. Moreover, prostate cancer stem cells are abundant in holoclone.

Downregulation of lncRNA CASC2 by microRNA-21 increases the proliferation and migration of renal cell carcinoma cells.

Several long non-coding RNAs (lncRNAs) have been identified that may have a crucial role in tumor progression and metastasis. The lncRNA cancer susceptibility candidate 2 (CASC2) has previously been reported to act as a tumor suppressor gene in glioma and colorectal cancer. However, the expression and function of CASC2 in renal cell carcinoma (RCC) remains to be elucidated. The present study confirmed that CASC2 was downregulated in human RCC tissues and human RCC cell lines (786­O and A498). Restoration of CASC2 expression via transfection with a pcDNA3.1(+)­CASC2 vector was able to inhibit cell proliferation and migration in 786­O and A498 cells, as compared with in the cells transfected with a pcDNA3.1(+) empty vector. MicroRNA­21 (miR­21) has been reported to be upregulated in human RCC tissues and cell lines, and is associated with the malignant progression of RCC. In the present study, bioinformatics analysis and dual­luciferase reporter assays confirmed that CASC2 was a direct target gene of miR­21. miR­21 was able to decrease the expression of CASC2 in 786­O and A498 cells. Furthermore, overexpression of miR­21 partly abrogated CASC2­mediated inhibition of 786­O and A498 cell proliferation and migration. The present study provides evidence indicating that CASC2 targeted by miR­21 acts as a tumor suppressor in RCC. Therefore, CASC2 may be considered a novel target for the diagnosis and treatment of RCC.

Anti-tumor effect of RGD modified PTX loaded liposome on prostatic cancer.

In this study, we report an active targeting liposomal formulation directed by a novel peptide (RGD) that specifically binds to the integrins receptors overexpressed on prostatic cancer cells. The objectives of this study were to evaluate the in vitro and in vivo tumor drug targeting delivery of RGD modified liposomes on PC-3 cells and DU145 cells. The uptake efficiency of RGD-LP was 5.2 times higher than that of LP on PC-3 cells. The uptake efficiency of RGD-LP was 3.2 times higher than that of LP on DU145 cells. The anti-proliferative activity of RGD-LP-PTX against PC-3 cells and DU145 cells were much stronger compared to that of LP-PTX and free PTX, respectively. The tumor spheroids experiment revealed that RGD-LP-PTX was more efficaciously internalized into tumor spheroids than LP in both PC-3 cells and DU145 cells. Compared to LP-PTX and free PTX, RGD-LP-PTX showed the greatest tumor growth inhibitory effect in vivo. In brief, the RGD-LP may be an efficient targeting drug delivery system for prostatic cancer.

Capn4 mRNA level is correlated with tumour progression and clinical outcome in clear cell renal cell carcinoma.

OBJECTIVE: To investigate the mRNA and protein levels of calpain small subunit-1 (Capn4) in human clear cell renal cell carcinoma (ccRCC), to analyse the relationship between Capn4 mRNA level and pathological stage of ccRCC, and to examine the potential of Capn4 as a prognostic factor in ccRCC. METHODS: mRNA and protein levels of Capn4 were measured in pairs of tumour tissues and matched adjacent nontumour tissue obtained from patients with ccRCC by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western blotting, respectively. Associations of the mRNA level of Capn4 with pathological tumour stage and the overall survival of ccRCC patients were also analysed. RESULTS: Capn4 mRNA and protein level were significantly higher in ccRCC tumour tissues compared with adjacent nontumour tissues as assessed by qRT-PCR and Western blotting, respectively. Higher Capn4 mRNA levels were observed in patients with more advanced pathological stage of ccRCC and were also associated with decreased overall survival of patients with ccRCC. CONCLUSIONS: The findings from this study indicate that Capn4 has the potential to be an independent prognostic indicator for ccRCC.

Comparison study on statistical features of predicted secondary structures for protein structural class prediction: From content to position.

BACKGROUND: Many content-based statistical features of secondary structural elements (CBF-PSSEs) have been proposed and achieved promising results in protein structural class prediction, but until now position distribution of the successive occurrences of an element in predicted secondary structure sequences hasn't been used. It is necessary to extract some appropriate position-based features of the secondary structural elements for prediction task. RESULTS: We proposed some position-based features of predicted secondary structural elements (PBF-PSSEs) and assessed their intrinsic ability relative to the available CBF-PSSEs, which not only offers a systematic and quantitative experimental assessment of these statistical features, but also naturally complements the available comparison of the CBF-PSSEs. We also analyzed the performance of the CBF-PSSEs combined with the PBF-PSSE and further constructed a new combined feature set, PBF11CBF-PSSE. Based on these experiments, novel valuable guidelines for the use of PBF-PSSEs and CBF-PSSEs were obtained. CONCLUSIONS: PBF-PSSEs and CBF-PSSEs have a compelling impact on protein structural class prediction. When combining with the PBF-PSSE, most of the CBF-PSSEs get a great improvement over the prediction accuracies, so the PBF-PSSEs and the CBF-PSSEs have to work closely so as to make significant and complementary contributions to protein structural class prediction. Besides, the proposed PBF-PSSE's performance is extremely sensitive to the choice of parameter k. In summary, our quantitative analysis verifies that exploring the position information of predicted secondary structural elements is a promising way to improve the abilities of protein structural class prediction.

MicroRNA-99a induces G1-phase cell cycle arrest and suppresses tumorigenicity in renal cell carcinoma.

BACKGROUND: A growing body of evidence suggests that microRNAs (miRNAs) play an important role in cancer diagnosis and therapy. MicroRNA-99a (miR-99a), a potential tumor suppressor, is downregulated in several human malignancies. The expression and function of miR-99a, however, have not been investigated in human renal cell carcinoma (RCC) so far. We therefore examined the expression of miR-99a in RCC cell lines and tissues, and assessed the impact of miR-99a on the tumorigenesis of RCC. METHODS: MiR-99a levels in 40 pairs of RCC and matched adjacent non-tumor tissues were assessed by real-time quantitative Reverse Transcription PCR (qRT-PCR). The RCC cell lines 786-O and OS-RC-2 were transfected with miR-99a mimics to restore the expression of miR-99a. The effects of miR-99a were then assessed by cell proliferation, cell cycle, transwell, and colony formation assay. A murine xenograft model of RCC was used to confirm the effect of miR-99a on tumorigenicity in vivo. Potential target genes were identified by western blotting and luciferase reporter assay. RESULTS: We found that miR-99a was remarkably downregulated in RCC and low expression level of miR-99a was correlated with poor survival of RCC patients. Restoration of miR-99a dramatically suppressed RCC cells growth, clonability, migration and invasion as well as induced G1-phase cell cycle arrest in vitro. Moreover, intratumoral delivery of miR-99a could inhibit tumor growth in murine xenograft models of human RCC. In addition, we also fond that mammalian target of rapamycin (mTOR) was a direct target of miR-99a in RCC cells. Furthermore, siRNA-mediated knockdown of mTOR partially phenocopied the effect of miR-99a overexpression, suggesting that the tumor suppressive role of miR-99a may be mediated primarily through mTOR regulation. CONCLUSIONS: Collectively, these results demonstrate for the first time, to our knowledge, that deregulation of miR-99a is involved in the etiology of RCC partially via direct targeting mTOR pathway, which suggests that miR-99a may offer an attractive new target for diagnostic and therapeutic intervention in RCC.