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The regulation of entry into and progression through mitosis is important for cell proliferation. Polo-like kinase 1 (PLK1) is involved in multiple stages of mitosis. Forkhead box protein M1 (FOXM1) has multiple functions in tumori-genesis and, in elevated levels, is frequently associated with cancer progression. The present study reports that FOXM1, a substrate of PLK1, controls the transcription mechanism that mediates the PLK1- dependent regulation of the cell cycle. The present study investigated the expression of PLK1 and FOXM1 in the clear renal cell carcinoma 769-P and ACHN cell lines, and indicated that the expression of PLK1 and FOXM1 are correlated in human renal cell cancer cell lines and that the suppression of PLK1 may decrease the expression of FOXM1. The knockdown of FOXM1 or PLK1 in renal cell cancer cell lines caused cell cycle progression to be blocked. As a result, the present study indicated the involvement of FOXM1 in PLK1-regulated cell cycle progression. [ABSTRACT FROM AUTHOR]

Background/objective: MicroRNAs (miRNAs) are small noncoding RNAs (ribonucleic acids), approximately 22 nucleotides in length, that function as regulators of gene expression. Dysregulation of miRNAs has been associated with the initiation and progression of oncogenesis in humans. The cell division cycle (CDC)25 phosphatases are important regulators of the cell cycle. Their abnormal expression detected in a number of tumors implies that their dysregulation is involved in malignant transformation. Methods: Using miRNA target prediction software, we found that miR-141 could target the 3' untranslated region (3'UTR) sequence of CDC25B. To shed light on the role of miR-141 in renal cell carcinogenesis, the expression of miR-141 was examined by real-time polymerase chain reaction (RT-PCR) in renal cell carcinoma and normal tissues. The impact of miR-141 re-expression on 769-P cells was analyzed using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and colony-forming assay. A luciferase reporter assay was applied to prove the functionality of the miR-141 binding site. Results: miR-141 is significantly downregulated in renal cell carcinoma. miR-141 re-expression suppressed cell growth in 769-P cells. Luciferase expression from a reporter vector containing the CDC25B-3'UTR was decreased when this construct was transfected with miR-141 in 769-P cells. The overexpression of miR-141 suppressed the endogenous CDC25B protein level in 769-P cells. Conclusion: For the first time, we demonstrated that CDC25B is a direct target of miR-141 in renal cell carcinoma. The transcriptional loss of miR-141 and the resultant increase in CDC25B expression facilitates increased genomic instability at an early stage of renal cell carcinoma development. [ABSTRACT FROM AUTHOR]

Cohesin regulates sister chromatid cohesion during the mitotic cell cycle with Nipped-B-Like (NIPBL) facilitating its loading and unloading. In addition to this canonical role, cohesin has also been demonstrated to play a critical role in regulation of gene expression in nondividing cells. Heterozygous mutations in the cohesin regulator NIPBL or cohesin structural components SMC1A and SMC3 result in the multisystem developmental disorder Cornelia de Lange Syndrome (CdLS). Genome-wide assessment of transcription in 16 mutant cell lines from severely affected CdLS probands has identified a unique profile of dysregulated gene expression that was validated in an additional 101 samples and correlates with phenotypic severity. This profile could serve as a diagnostic and classification tool. Cohesin binding analysis demonstrates a preference for intergenic regions suggesting a cis-regulatory function mimicking that of a boundary/insulator interacting protein. However, the binding sites are enriched within the promoter regions of the dysregulated genes and are significantly decreased in CdLS proband, indicating an alternative role of cohesin as a transcription factor. [ABSTRACT FROM AUTHOR]

Cytoplasmic polyadenylation element-binding protein 3 (CPEB3) is a member of the Cytoplasmic polyadenylation element-binding family, which has been found to regulate the translation of dormant and masked mRNA in Xenopus oocytes and plays potential roles in regulating biological functions in cells and tissues. However, its role in cumulus cells is not clear. In this study, the mRNA expression of CPEB3 in bovine cumulus cells was inhibited with small interfering RNA. Cell cycle progression, proliferation, and apoptosis were measured after inhibition of CPEB3. Subsequently, changes in intracellular Reactive oxygen species content, mitochondrial membrane potential and expansion-related gene expression were examined. The results showed that after CPEB3 inhibition, cumulus cells had an abnormal cell cycle, the numbers of cells in the S and G2/M phases were significantly increased, cell proliferation was increased and apoptosis rates were decreased. These effects were likely due CPEB3 inhibition-induced decreases in intracellular Reactive oxygen species levels; increases in mitochondrial membrane potential; decreases in apoptosis; downregulation of CCNA, CCND, CCNE, CDK2, CDK4, CDK6, p21, and p27 mRNA expression; and upregulation of CCNB, CDK1, HAS2, PTGS2, PTX3, and CEBPB mRNA expression. Therefore, CPEB3 plays potential roles in regulating the biological and physiological functions of bovine cumulus cell. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effect of sinomenine on the proliferation and apoptosis of oral squamous cell carcinoma cells (OCSSs), and its underlying mechanism of action. Methods: CCK-8 method was used to determine the inhibitory effects of different concentrations of sinomenine (50, 100, 200, 400 and 800 ug/mL) on proliferation of CAL-27 cells on treatment for 24 and 48 h. Cell migration was assayed using scratch test, while cell cycle was measured by flow cytometry. Hoechst 33258 fluorescence staining was conducted to determine apoptotic morphology. The effect of sinomenine on the expressions of cyclinD1, cyclinD3, cyclin-dependent kinases-2 (CDK2), Bax, B-cell lymphoma/leukmia-2 (Bcl-2), Caspase-3 and Caspase-9 was determined by western-blotting (WB). Results: Sinomenine significantly inhibited proliferation and migration of CAL-27 cells in a concentration-dependent manner, but not in a time-dependent fashion. It inhibited the transition from G0/G1 phase to S phase in CAL-27 cells. Sinomenine treatment also caused dispersion of CAL-27 cells. Moreover, the nuclei were pyknotic, and the cells translucent, indicating typical features of apoptotic morphology. Expressions of Bax, caspase 3 and caspase 9 protein were significantly upregulated, while expressions of Bcl-2, cyclinD1, cyclinD3 and CDK2 protein were down-regulated by sinomenine. Conclusion: Sinomenine induces apoptosis of OSCCs, and inhibits their proliferation and migration via a mechanism associated with up-regulation of Bax, Caspase-3 and Caspase-9, and down-regulation of Bcl-2. [ABSTRACT FROM AUTHOR]

Background: The netrin-1 receptor UNC5B plays vital roles in angiogenesis, inflammation, embryonic development and carcinogenesis. However, the functional significance of UNC5B overexpression in bladder cancer remains unclear. In this study, we investigated the role of UNC5B in bladder cancer in vitro and in vivo. Methods: Stable transfection of the human bladder cancer cell line 5637 with UNC5B (5637-U) was confirmed by real-time RT-PCR, western blot and immunofluorescence assays. UNC5B expression in 5637 and 5637-U cells and mice tumor specimens derived from these cell lines was analyzed by immunohistochemistryand western blotting. Changes in the levels of cell cycle proteins were evaluated by western blotting. Flow cytometry, CCK-8 and scratch tests were used to examine cell cycle distribution, proliferation and migration, respectively. Results: UNC5B overexpression in 5637 cells inhibited cell multiplication and migration and induced cell cycle arrest at the G2/M phase, meanwhile exhibited changes in the expression of cell cycle-associated proteins, showing that UNC5B may inhibit metastatic behaviors in bladder cancer cells. In addition, tumors generated from 5637-U cells were smaller than tumors generated from control 5637 cells. Conclusions: Our findings suggest that UNC5B is a potential anti-neoplastic target in bladder cancer progression. [ABSTRACT FROM AUTHOR]

The peripheral nervous system has the potential for full regeneration following injury and recovery, predominantly controlled by Schwann cells (SCs). Therefore, obtaining a sufficient number of SCs in a short duration is crucial. In the present study, rat adipose-derived stem cells (ADSCs) were isolated and cultured, following which characterization of the ADSCs was performed using flow cytometry. The results showed that the cells were positive for the CD29 and CD44 markers, and negative for the CD31, CD45, CD49 and CD106 markers. The multilineage differentiation potential of the ADSCs was assayed by determining the ability of the cells to differentiate into osteoblasts and adipocytes. Following this, the ADSCs were treated with a specific medium and differentiated into Schwann-like cells. Immunofluorescence, western blot and reverse transcription-quantitative polymerase chain reaction analyses showed that ~95% of the differentiated cells expressed glial fibrillary acidic protein, S100 and p75. In addition, the present study found that a substantial number of SCs can be produced in a short duration via the mitotic feature of Schwann-like cells. These data indicated that Schwann-like cells derived from ADSCs can undergo mitotic proliferation, which may be beneficial for the treatment of peripheral nerve injury in the future. [ABSTRACT FROM AUTHOR]

Background: Aberrant modulation of store-operated calcium ions (Ca2+) entry promotes the progression of human malignancies. Previously, we reported that the blockage of storeoperated Ca2+ entry inhibited epidermal growth factor (EGF)-stimulated migration and distant metastasis in nasopharyngeal carcinoma (NPC) cells. However, the effects of pharmacological blocker on other Ca2+ signaling-regulated malignant characteristics in NPC cells remained poorly understood. Methods: We examined the effects of SKF96365, an inhibitor of store-operated Ca2+ channel, on EGF-launched Ca2+ signaling in two NPC cell lines. We determined the effects of SKF96365 on cell proliferation, colony formation, apoptosis, and cell-cycle status in vitro. We further elucidated the antitumor activity of SKF96365 in xenograft-bearing mice. Results: It was found that SKF96365 disturbed the thapsigargin (TG)-stimulated Ca2+ release from endoplasmic reticulum and the subsequent Ca2+ influx. SKF96365 alone stimulated Ca2+ responses merely due to endoplasmic reticulum-released Ca2+. SKF96365 promoted cell mortality, inhibited colony formation, and induced apoptosis and cell-cycle arrest, while blunting the EGF-evoked Ca2+ signaling. Furthermore, we confirmed that SKF96365 reduced NPC xenograft growth while activating caspase-7-related apoptotic pathway. Conclusion: SKF96365 exerts multiple antitumor activities through the distraction on the oncogenic Ca2+ signaling transduction in NPC cells. [ABSTRACT FROM AUTHOR]