EHMT2 promotes the development of prostate cancer by inhibiting PI3K/AKT/mTOR pathway.

OBJECTIVE: To investigate the expression characteristics and the potential role of euchromatic histone-lysine N-methyltransferase 2 (EHMT2) in the clinical pathology and prognosis of prostate cancer (PCa). PATIENTS AND METHODS: Quantitative Real-time polymerase chain reaction (qRT-PCR) was performed to detect the expression of EHMT2 in 55 pairs of PCa tissues and adjacent normal tissues. The relationship between EHMT2 expression and the pathological features, as well as the prognosis of PCa patients was analyzed. EHMT2 expression in PCa cells was determined by qRT-PCR as well. In addition, EHMT2 knockdown model was constructed by transfection of the small interfering RNA in PCa cell lines PC-3 and DU-145. The regulatory effects of EHMT2 on the behaviors of PCa cells were evaluated through cell counting kit-8 (CCK-8), 5-Ethynyl-2'-deoxyuridine (EdU), colony formation assay and flow cytometry. Finally, we detected the protein levels of relative genes in PI3K/AKT/mTOR pathway through Western blot. RESULTS: QRT-PCR results showed that the expression level of EHMT2 in PCa tissues was markedly higher than that in adjacent normal tissues. Compared with PCa patients with low expression of EHMT2, those with high expression of EHMT2 had higher pathological grade and lower overall survival. EHMT2 was also highly expressed in PCa cell lines. Knockdown of EHMT2 inhibited the proliferative potential and induced apoptosis of PCa cells. Western blot results revealed that PCa cells with EHMT2 knockdown presented downregulated p-PI3K, p-AKT and p-mTOR. CONCLUSIONS: EHMT2 was highly expressed in PCa, and its expression is closely correlated with tumor stage and poor prognosis of PCa patients. EHMT2 promoted the malignant progression of PCa by inhibiting PI3K/AKT/mTOR pathway.

Up-regulation of LncRNA MEG3 inhibits cell migration and invasion and enhances cisplatin chemosensitivity in bladder cancer cells.

It has been proven that maternally expressed 3 (MEG3), a long non-coding RNA (LncRNA), is down-regulated and inversely correlated with prognosis in various types of cancer, including bladder cancer (BC). Nevertheless, the role of MEG3 in BC has not been fully identified. Herein, we found that MEG3 expression was reduced in 21 BC tumor tissue samples compared to corresponding adjacent tissues. We then established T24 and 5637 cells with a stably integrated expression of MEG3 by G418 resistance screening, and data revealed that the BC cells over-expressing MEG3 displayed weaker migration and invasion ability than control cells. The expression and activity of matrix metalloproteinase (MMP)2 and MMP9 were down-regulated when MEG3 was over-expressed. Moreover, MEG3 over-expression sensitized BC cells to the chemotherapy drug cisplatin (DDP). DDP treatment significantly induced cell apoptosis, down-regulated bcl2 expression, and up-regulated cleaved-caspase-3 and bax expression in BC cells with MEG3 over-expression. MEG3 and p53 can also stimulate mutual expression in BC cells, thus indicating a potential positive feedback loop of MEG3 and p53. Our combined results suggest that over-expression of MEG3 inhibits migration and invasion and enhances DDP chemo-sensitivity in bladder cancer cells.

Structural chromosomal abnormalities in couples in cases of recurrent spontaneous abortions in Jilin Province, China.

Recurrent spontaneous abortions (RSAs) occur in approximately 15 to 20% of all clinically recognizable pregnancies. Structural chromosome abnormalities result in increased risk of pregnancy loss. Parental chromosomal abnormalities are an important genetic cause of RSAs. Some cytogenetic investigations have been performed in various countries and regions to determine the pattern of chromosomal abnormalities in parents with RSAs. The aim of this study was to report the prevalence and type of structural chromosomal abnormalities in couples in cases of RSAs in Jilin Province, China. The prevalence of structural chromosomal abnormalities in these couples was 2.98%. The number of female carriers with balanced chromosomal aberrations significantly exceeded that of such male carriers, and the ratio of female/male carriers was approximately 2:1. The number of abortions in the case of female carriers was more than that for male carriers before the structural chromosome abnormality was diagnosed. This indicates that genetic counseling for couples with structural chromosomal abnormalities should consider the gender of the carriers.

Genetic screening and evaluation for chromosomal abnormalities of infertile males in Jilin Province, China.

Chromosomal abnormality is the most common genetic cause of male infertility, particularly in cases of azoospermia, oligozoospermia, and recurrent spontaneous abortion. Chromosomal rearrangement may interrupt an important gene or exert position effects. The functionality of genes at specific breakpoints, perhaps with a specific role in spermatogenesis, may be altered by such rearrangements. Structural chromosome abnormalities are furthermore known to increase the risk of pregnancy loss. In this study, we aimed to assess chromosomal defects in infertile men from Jilin Province, China, by genetic screening and to evaluate the relationship between structural chromosome abnormalities and male infertility. The prevalence of chromosomal abnormalities among the study participants (receiving genetic counseling in Jilin Province, China) was 10.55%. The most common chromosome abnormality was Klinefelter syndrome, and the study findings suggested that azoospermia and oligospermia may result from structural chromosomal abnormalities. Chromosome 1 was shown to be most commonly involved in male infertility and balanced chromosomal translocation was identified as one of the causes of recurrent spontaneous abortion. Chromosomes 4, 7, and 10 were the most commonly involved chromosomes in male partners of women experiencing repeated abortion.

Clinical characteristics of men with non-mosaic Klinefelter syndrome in northeastern China: implications for genetic counseling.

Klinefelter syndrome (KS) is the most common genetic cause of male infertility. Widespread development in assisted reproductive technology has provided non-mosaic KS patients with the opportunity of having biological children. Testosterone replacement therapy and micro-dissection testicular sperm extraction are effective sperm retrieval techniques for KS patients. Despite the success of sperm retrieval and intracytoplasmic sperm injection (ICSI), some areas of early aggressive hormonal spermatogenesis and appropriate management of KS remain controversial. Androgenotherapy, a common treatment for KS, carries a risk of decreasing focal spermatogenesis by lowering the gonadotropin content. Inadequately treated hypogonadism increases psychosocial morbidity in KS patients. Preventive care must be provided from the time of diagnosis, preferentially through a multidisciplinary approach. This indicates the need for improved genetic counseling of KS patients. The aim of this study was to report the prevalence of non-mosaic KS in a Chinese infertile male population. The rate of early diagnosis was lower in KS patients; most of these were diagnosed after rising concerns of reproductive capacity. The mean age of patients with sperm or germ cells was significantly lower, while the semen volume of these patients was significantly higher. However, the semen volume was negatively correlated with the age and ratio of luteinizing hormone/testosterone content in KS patients. Therefore, genetic counseling of KS patients should focus on early diagnosis and timely treatment, in addition to improving the quality of life of all KS patients. The use of testosterone replacement therapy and/ or micro-dissection testicular sperm extraction should be preferentially considered for fertility preservation.

A simple empirical model for the clarification-thickening process in wastewater treatment plants.

In wastewater treatment plants (WWTPs), activated sludge is thickened in secondary settling tanks and recycled into the biological reactor to maintain enough biomass for wastewater treatment. Accurately estimating the activated sludge concentration in the lower portion of the secondary clarifiers is of great importance for evaluating and controlling the sludge recycled ratio, ensuring smooth and efficient operation of the WWTP. By dividing the overall activated sludge-thickening curve into a hindered zone and a compression zone, an empirical model describing activated sludge thickening in the compression zone was obtained by empirical regression. This empirical model was developed through experiments conducted using sludge from five WWTPs, and validated by the measured data from a sixth WWTP, which fit the model well (R² = 0.98, p < 0.001). The model requires application of only one parameter, the sludge volume index (SVI), which is readily incorporated into routine analysis. By combining this model with the conservation of mass equation, an empirical model for compression settling was also developed. Finally, the effects of denitrification and addition of a polymer were also analysed because of their effect on sludge thickening, which can be useful for WWTP operation, e.g., improving wastewater treatment or the proper use of the polymer.

An exploration on the radiological features associated with motor deficits in patients with metastatic epidural spinal cord compression.

OBJECTIVE: This study was designed to explore the radiological features associated with the motor deficits in patients with metastatic epidural spinal cord compression (MESCC). PATIENTS AND METHODS: The patients with MESCC admitted in our department from July 2006 to December 2008 were included in this analysis. The data on the radiological features of affected vertebrae showed by computed tomography or magnetic resonance imaging scan and the motor deficits level assessed as paralysis or non-paralysis according to Frankel Classification Grading System were collected. A multiple regression model was established to indentify the radiological features associated with the paralysis status of MESCC patients. RESULTS: A total of 56 patients with MESCC were included in this study. All patients had invasion of vertebral body, main affected vertebrae was consecutive in 75% (8/12) of patients with lesions of upper thoracic spine and/or cervicothoracic junction and 18.18% (8/44) of patients with lesions of cervical spine, middle thoracic spine, lower thoracic spine, and lumbar spine. The paralysis status was consisted with the finding of epidural space involvement. A linear relationship between paralysis status and the radiological features including lamina involvement, retropulsion of posterior wall, and location in upper thoracic spine and/or cervicothoracic junction was detected by the "optimal" regression equation, of them lamina involvement has the greatest impact on paralysis status. CONCLUSIONS: The radiological features including lamina involvement, retropulsion of posterior wall, and location in upper thoracic spine and/or cervicothoracic junction were significantly associated with the motor deficits of patients with MESCC, which might be helpful to identify these patients who were susceptible to motor deficit, especially lamina involvement.

Formation of liquid sheets by deposition of droplets on a surface.

Experiments were done to observe the coalescence of highly viscous liquid droplets (87 wt% glycerin-in-water solutions) deposited onto a flat, solid steel plate. Droplets were deposited sequentially in straight lines or square droplet arrays. Droplet center-to-center distance was varied and the final dimensions of lines and sheets measured from photographs. When overlapping droplets were deposited surface tension forces pulled impacting droplets towards those already on the surface, a phenomena known as drawback. A dimensionless drawback index, quantifying the extent of droplet displacement, was calculated from experimental measurements for different values of droplet overlap. At large overlaps droplets deposited in a line or square array coalesced to form a circular film. When the droplet center-to-center distance increased, leading to less interaction, long, thin lines and square sheets were formed. As overlap was further decreased lines and sheets became discontinuous. A simple model was developed to predict the conditions under which rupture occurred. The lowest droplet overlap ratio (defined as droplet overlap distance divided by droplet spread diameter) at which a continuous liquid film could be formed was λ=0.293. At large overlap ratios (λ>0.6) droplets deposited in a square array formed a circular film. The minimum thickness of a continuous film formed by coalescence of droplets was shown to vary from 5% to 70% of the initial droplet diameter while increasing impact Weber and Reynolds number reduced the film thickness.

Note: A new angle-resolved proton energy spectrometer.

In typical laser-driven proton acceleration experiments Thomson parabola proton spectrometers are used to measure the proton spectra with very small acceptance angle in specific directions. Stacks composed of CR-39 nuclear track detectors, imaging plates, or radiochromic films are used to measure the angular distributions of the proton beams, respectively. In this paper, a new proton spectrometer, which can measure the spectra and angular distributions simultaneously, has been designed. Proton acceleration experiments performed on the Xtreme light III laser system demonstrates that the spectrometer can give angle-resolved spectra with a large acceptance angle. This will be conductive to revealing the acceleration mechanisms, optimization, and applications of laser-driven proton beams.

A novel polysaccharide, isolated from Angelica sinensis (Oliv.) Diels induces the apoptosis of cervical cancer HeLa cells through an intrinsic apoptotic pathway.

A novel polysaccharide isolated from Angelica sinensis, named APS-1d showed cytotoxic activity towards several cancer cell lines in vitro. However, the precise antitumor mechanisms of this compound are unknown. In this study, we investigated the pro-apoptotic effects of APS-1d in human cervical cancer HeLa cells both in vitro and in vivo, and further elucidated the mechanisms of this action. Inhibition of HeLa cell proliferation was determined by MTT assay and the therapeutic efficacy of APS-1d was evaluated by human cancer xenografts in nude mice. Cell apoptosis was examined with flow cytometry and TUNEL assay. The mechanism of action of APS-1d was investigated by Western blot analysis. APS-1d decreased HeLa cell proliferation in a concentration- and time-dependent manner in vitro. In addition, APS-1d significantly inhibited tumor growth in athymic nude mice. Characteristic manifestations of apoptosis including apoptotic morphological features and the sub- G(0)/G(1) peaks were observed when the cells were treated with APS-1d. Further analysis showed that APS-1d-induced apoptosis was associated with the regulation of Bcl-2 family protein expression, a decrease in the mitochondrial membrane potential, and an increase in the cytosolic cytochrome c levels. Sequentially, APS-1d increased the activities of caspase-9, -3, and poly (ADP-ribose) polymerase in a concentration-dependent manner, however, no obvious activation of Bid and caspase-8 was observed. Pretreatment with Z-LEHD-FMK, a specific inhibitor of caspase-9, significantly attenuated APS-1d-induced cell apoptosis, and activation of caspase-3. Taken together, our studies indicate that APS-1d is capable of inhibiting HeLa cell proliferation and inducing apoptosis in these cells which primarily involves the activation of the intrinsic mitochondrial pathway.

Phloretin differentially inhibits volume-sensitive and cyclic AMP-activated, but not Ca-activated, Cl(-) channels.

Some phenol derivatives are known to block volume-sensitive Cl(-) channels. However, effects on the channel of the bisphenol phloretin, which is a known blocker of glucose uniport and anion antiport, have not been examined. In the present study, we investigated the effects of phloretin on volume-sensitive Cl(-) channels in comparison with cyclic AMP-activated CFTR Cl(-) channels and Ca(2+)-activated Cl(-) channels using the whole-cell patch-clamp technique. Extracellular application of phloretin (over 10 microM) voltage-independently, and in a concentration-dependent manner (IC(50) approximately 30 microM), inhibited the Cl(-) current activated by a hypotonic challenge in human epithelial T84, Intestine 407 cells and mouse mammary C127/CFTR cells. In contrast, at 30 microM phloretin failed to inhibit cyclic AMP-activated Cl(-) currents in T84 and C127/CFTR cells. Higher concentrations (over 100 microM) of phloretin, however, partially inhibited the CFTR Cl(-) currents in a voltage-dependent manner. At 30 and 300 microM, phloretin showed no inhibitory effect on Ca(2+)-dependent Cl(-) currents induced by ionomycin in T84 cells. It is concluded that phloretin preferentially blocks volume-sensitive Cl(-) channels at low concentrations (below 100 microM) and also inhibits cyclic AMP-activated Cl(-) channels at higher concentrations, whereas phloretin does not inhibit Ca(2+)-activated Cl(-) channels in epithelial cells.

Swelling-activated, cystic fibrosis transmembrane conductance regulator-augmented ATP release and Cl- conductances in murine C127 cells.

1. A hypotonic challenge, but not cAMP stimulation, was found to induce release of ATP measured by the luciferin-luciferase assay from both the murine mammary carcinoma cell line C127i and C127 cells stably transfected with the cDNA for human cystic fibrosis transmembrane conductance regulator (CFTR) protein (C127/CFTR). CFTR expression augmented swelling-induced ATP release by 10-20 times under hypotonic conditions (< or = 80 % osmolality). 2. Glibenclamide failed to suppress swelling-induced ATP release from C127/CFTR cells. In contrast, whole-cell patch-clamp recordings showed that both the cAMP-activated ohmic Cl- currents and volume-sensitive outwardly rectifying (VSOR) Cl- currents were prominently suppressed by glibenclamide. 3. Gd3+ markedly blocked swelling-induced ATP release but failed to suppress both cAMP- and swelling-activated Cl- currents in the CFTR-expressing cells. Even after pretreatment and during treatment with Gd3+, VSOR Cl- currents were activated normally. 4. The continuous presence of an ATP-hydrolysing enzyme, apyrase, in the bathing solution did not prevent activation of VSOR Cl- currents in C127/CFTR cells. 5. The rate of regulatory volume decrease (RVD) in C127/CFTR cells was much faster than that in C127i cells. When apyrase was added to the bathing solution, the RVD rate was retarded in C127/CFTR cells. 6. On balance, the following conclusions can be deduced. First, swelling-induced ATP release is augmented by expression of CFTR but is not mediated by the CFTR Cl- channel. Second, swelling-induced ATP release is not mediated by the VSOR Cl- channel. Third, the released ATP facilitated the RVD process but is not involved in the activation of VSOR Cl- channels in C127/CFTR cells.