Molecular Mediators of Estrogen Reduction-induced Otolith Shedding.

OBJECTIVE: Previous study suggested that estradiol (E2) plays an important role in otolith shedding by regulating the expression of otoconin 90 (OC90). The purpose of this article is to provide further data on the effect and mechanism of E2 on the morphology of otolith. METHODS: The rats receiving bilateral ovariectomy (OVX) were used as animal models. Co-immunoprecipitation was used to observe the relationship between estrogen receptor (ER) and estrogen-related receptor α (ERRα). The morphology of otolith was observed under the scanning electron microscopy. Western blotting and qPCR were used for quantitative analysis of the roles of ER and ERRα in regulating OC90 expression. RESULTS: The looser otoliths were observed in rats receiving bilateral OVX, which could be reversed by supplementation with E2. The level of ERRα was decreased in bilateral OVX rats. ER and ERRα interacted with each other on the regulation of the expression of OC90. CONCLUSION: Our results suggest ER and ERRα are both important downstream receptors involved in regulating OC90 expression in utricles of rats, and ERRα probably functions by interacting with ER. This provides evidence for the mechanism of otolith shedding. And it may be significant for future studies of targeted prevention and therapies for benign paroxysmal positional vertigo.

Panax ginseng polysaccharide induces apoptosis by targeting Twist/AKR1C2/NF-1 pathway in human gastric cancer.

In the present study, we isolated and screened an antitumor polysaccharide (PGP2a) from the roots of Panax ginseng. Chemical composition analysis indicated PGP2a was an acidic protein-polysaccharide. The average molecular weight was estimated to be 3.2 × 10(4)Da. According to gas chromatography (GC) result, PGP2a consisted of galactose, arabinose, glucose and galacturonic acid in the molar ratio of 3.7:1.6:0.5:5.4, respectively. MTT assay showed that PGP2a had a potent inhibitory effect on the growth of HGC-27 cells in a dose-dependent fashion. Furthermore, the number of HGC-27 cells arrested in G2/M phase, and the percentage of apoptotic cells were increased in response to PGP2a treatment along with concentration increasing. Moreover, western blotting analysis showed that protein expressions of Twist and AKR1C2 were suppressed by PGP2a, whereas an increase of NF1 was observed at protein level. Taken together, these findings suggested that PGP2a could be developed as a novel antitumor agent acting on Twist related gene for human gastric cancer therapy.

Daytime fluctuation of intraocular pressure in patients with primary angle-closure glaucoma after trabeculectomy.

PURPOSE: To evaluate the daytime fluctuation of intraocular pressure (IOP) in patients with primary angle-closure glaucoma (PACG) after trabeculectomy. PARTICIPANTS AND METHODS: A total of 176 patients with PACG participated in a clinical trial of trabeculectomy with or without releasable sutures. Applanation IOP was measured at 5, 7, and 10 AM, and 2, 6, and 10 PM at 3 months posttrabeculectomy. We documented the mean, peak, and trough IOPs, determined the fluctuation of daytime IOP, and explored the associations of IOP fluctuation with baseline factors. RESULTS: IOP measurements were obtained in 173 patients. The mean daytime IOP was 13.2±3.7 mm Hg; mean peak IOP 15.1±4.1 mm Hg, mean trough IOP 11.3±3.5 mm Hg, and mean fluctuation 3.8±2.1 mm Hg. Fluctuation was positively correlated with peak (r=0.528, R2=0.28, P<0.001) and mean IOP (r=0.278, R2=0.08, P<0.001), but not with the trough IOP (r=0.015, P=0.843). Fluctuation was lower with extent of bleb (0.6 mm Hg/unit increase in extent; 95% CI, 0.1-1.2 mm Hg) and in blebs with microcysts (1.1 mm Hg less fluctuation; 95% CI, 0.2-1.9 mm Hg). Fluctuation was not associated with sex, age, baseline IOP, extent of peripheral anterior synechia or number of glaucoma medications before surgery, mean deviation of the visual field, vertical cup:disc ratio, or the use of releasable sutures. CONCLUSIONS: The mean fluctuation of daytime IOP after trabeculectomy for PACG was about 4 mm Hg. The fluctuation was positively associated with higher peak and mean IOP and negatively associated with extent of bleb and presence of microcysts.

Panax ginseng polysaccharide suppresses metastasis via modulating Twist expression in gastric cancer.

It was previously reported that an antitumor polysaccharide (PGPW1) was isolated from the root of Panax ginseng. To extend our study, we investigated here the anti-invasive and metastatic effects of PGPW1 on human gastric cancer cell line HGC-27 and tried to determine its possible mechanism of action. Both scratch wound-healing and Transwell assay identified that PGPW1 dose-dependently inhibited migration and invasiveness of HGC-27 cells. Furthermore, results of western blot showed that protein levels of Twist and AKR1C2 were inhibited by PGPW1, whereas an increase of NF1 was observed. Moreover, down-regulation of Twist expression by PGPW1 blocked epithelial-mesenchymal transition (EMT), characterized by a gain of epithelial cell markers, E-cadherin, and loss of the mesenchymal markers, vimentin and N-cadherin, at protein levels. Collectively, we confirmed that PGPW1 decreased migration and invasion of HGC-27 cells by regulation of Twist, AKR1C2, NF1, E-cadherin, vimentin and N-cadherin expression. In conclusion, PGPW1 may serve as a powerful chemopreventive agent against gastric cancer metastasis.

Involvement of Mcl1 in diallyl disulfide-induced G2/M cell cycle arrest in HL-60 cells.

Diallyl disulfide (DADS) has shown potential as a therapeutic agent in various cancers. Previously, we found that myeloid cell leukemia sequence 1 (Mcl1) was downregulated in DADS-induced cell cycle arrest in HL-60 human leukemia cells. Here, we investigated the role of this protein in DADS-induced G2/M cell cycle arrest in HL-60 cells. We demonstrated that DADS treatment significantly increased the proportion of G2/M phase HL-60 cells (P<0.05) and caused a time-dependent significant downregulation of Mcl1 and the cell cycle-related proteins PCNA and CDK1 (P<0.05). Small interfering RNA-mediated knockdown of Mcl1 expression in HL-60 cells arrested the cell cycle in G2/M phase. By co-immunoprecipitation, we demonstrated that Mcl1 associated with PCNA and CDK1 in G2/M cell cycle arrest in DADS-treated HL-60 cells. DADS decreased the interaction of Mcl1 with PCNA and CDK1, leading to G2/M cell cycle arrest in HL-60 cells. Mcl1 plays an important role in DADS-induced G2/M cell cycle arrest in HL-60 human leukemia cells.

[Assess correlation between bleb morphology at long-term intraocular pressure effect in primary angle-closure glaucoma following trabeculectomy].

OBJECTIVE: To evaluate the correlation between morphologic appearance of blebs at 3 month and long-term intraocular pressure (IOP) effect in patients with primary angle-closure glaucoma (PACG) after trabeculectomy. METHODS: Multi-centered cases series. Data were collected from 176 patients aged ≥ 40 years with PACG who were participated in a randomized clinical trial that aimed at addressing the efficacy of augmented releasable sutures after trabeculectomy. The bleb morphology was graded using the Modified Indian Bleb Appearance Grading Scale (IBAGS) based on standard photos at 3 month after trabeculectomy. IOPs were measured with Goldmann applanation tonometer. The correlation between bleb components and other selected testing influencing factors and long-term IOP was tested by linear Logistic regression analysis. RESULTS: 150 patients (85.7%) completed 18 months of follow up. IOP was (15.6 ± 5.4) mm Hg at 18 month of post-operation. 135 eyes had an IOP ≤ 21 mm Hg without additional medications, 10 eyes ≥ 21 mm Hg, and the remaining 5 eyes required one or two medications to maintain normal IOP. Using IBAGS system, bleb was graded in 142 eyes as follows: H(0) in 3 eyes, H(1) in 45 eyes, H(2) in 90 eyes, and H(3) in 4 eyes, while V(0) was observed in 66 eyes, V(1-3) in 76 eyes. IOP at 18 months in bleb with microcysts was 2.77 mm Hg lower (ß = -2.77, 95%CI = -0.46 to -5.08) than those without microcysts and in bleb with non-vascular was 2.07 mm Hg lower (ß = -2.07, 95%CI = -0.15 to -3.98) than those with vascular at 3 months after surgery. IOP was significantly (ß = -1.20, 95%CI: -0.00 to -2.40) decreased by 1.2 mm Hg with 10 years of age increase (P < 0.05). CONCLUSIONS: Early filtering bleb with microcysts, vascular, and age are identified as important factors to predict long-term IOP effect in patients with PACG after trabeculectomy but not early morphological appearance of filtering bleb.

Metastasis-induction and apoptosis-protection by TWIST in gastric cancer cells.

TWIST, a basic helix-loop-helix transcription factor, has been recently reported to play an important role in tumorigenesis of human cancer through converting the early stage tumors into invasive malignancies. Upregulation of TWIST is often found in cancer patients, especially those with shorter survival period and poor response to chemotherapy. Here we studied the functions of TWIST on regulating migration rate, apoptosis, and gene expression in gastric cancer cells. TWIST expression is elevated in MGC-803 and HGC-27 cells that exhibit high invasive potential; whereas it is reduced in BGC-823 and SGC-7901 cells that possess relatively low invasive content. To evaluate functional consequences of TWIST induction, we examined the effect of TWIST on cell migration and apoptosis. Overexpression of TWIST in BGC-823 cells resulted in increased migration content and decreased sensitivity to the arsenic oxide-induced cell death. Moreover, small interference RNA-mediated TWIST ablation in MGC-803 and HGC-27 cells showed suppressed migration ability, increased induction of apoptosis in response to arsenic oxide, and elevated cell cycle arrest. Furthermore, we found a negative correlation between the TWIST level and p53 level, probably due to transcriptional regulation. Our results have identified TWIST as a critical regulator of gastric cancer cell proliferation and migration, suggesting a potential therapeutic approach to inhibit the growth and metastasis of gastric cancer through inactivation of TWIST.

Gene expression profiling in TWIST-depleted gastric cancer cells.

TWIST is an important transcription factor during embryonic development and has recently been found to promote the epithelial-mesenchymal transition (EMT) phenomenon seen during the initial steps of tumor metastasis. To further investigate the potential targets and interacting genes of TWIST in human gastric cancer, we performed microarray analysis to compare the gene expression profiles in HGC-27 cells, with or without small interfering RNA (siRNA)-mediated depletion of TWIST. Our results showed that NF1, RAP1A, SRPX, RBL2, PFDN4, ILK, F2R, ERBB3, and MYB were up-regulated, whereas AKR1C2, FOS, GDF15, NR2F1, ATM, and CTPS were down-regulated after TWIST depletion. Moreover, TWIST-depleted HGC-27 cells showed a reversal of the morphologic and molecular changes associated with EMT. These results provide evidence that TWIST regulates the expression of several genes involved in the differentiation, adhesion, and proliferation of gastric cancer cells. The role of TWIST in the development of certain types of gastric cancer is discussed.

[Expression and clinical significance of Mucin and E-cadherin in colorectal tumors].

BACKGROUND & OBJECTIVE: Mucin (MUC), a glycoprotein with high molecular weight, can lubricate and protect the epithelium. E-cadherin (E-cad) is helpful in keeping the polarity and integrity of the epithelium. The abnormal expression of Mucin and E-cad is involved in the genesis of many tumors. This study was to investigate the expression of MUC1, MUC2, MUC5AC and E-cad in different colorectal tumor tissues, and explore their correlations to clinicopathologic features of colorectal cancer and the correlations of MUC1, MUC2, and MUC5AC expression to E-cad expression. METHODS: The expression of MUC1, MUC2, MUC5AC and E-cad in 150 specimens of normal colorectal mucosa, 150 specimens of colorectal adenoma and 150 specimens of colorectal adenocarcinoma was detected by immunohistochemistry. Patients' survival was analyzed by Kaplan-Meier method. The correlations of MUC1, MUC2, and MUC5AC expression to E-cad expression were analyzed by spearman's rank correlation. RESULTS: The positive rates of MUC1 were 0.07% in normal colorectal mucosa, 12.7% in colorectal adenoma, and 45.3% in colorectal adenocarcinoma. Those of MUC2 were 100%, 90.0% and 52.6%, respectively. Those of MUC5AC were 8.7%, 30.7% and 44.0%, respectively. Those of E-cad were 98.7%, 82.0% and 54.0%, respectively. In colorectal adenocarcinoma, the expression of MUC1 and MUC2 was correlated to tumor differentiation, invasion, lymph node metastasis and Dukes' stage (P<0.05); the expression of MUC5AC was correlated to tumor differentiation and invasion (P<0.01); the expression of E-cad was correlated to tumor differentiation (P<0.01). The 5-year survival rate was significantly higher in MUC1-negative group, MUC2-positive group and E-cadherin-positive group than in their counterparts (P<0.05). In colorectal adenocarcinoma, MUC1 expression was negatively correlated to E-cad expression (r=-0.234, P=0.004), MUC2 and MUC5AC expression were positively correlated to E-cad expression (r=0.170, P=0.038; r=0.198, P=0.015). CONCLUSIONS: In colorectal adenocarcinoma, MUC expression is obviously correlated to E-cad expression. The up-regulation of MUC1 and MUC5AC expression and the down-regulation of MUC2 and E-cad expression may be involved in the genesis of colorectal tumors and reflect the prognosis to a certain extent.