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Background: Advanced gastric cancer (GC) exhibits a high recurrence rate and a dismal prognosis. Myocyte enhancer factor 2c (MEF2C) was found to contribute to the development of various types of cancer. Therefore, our aim is to develop a prognostic model that predicts the prognosis of GC patients and initially explore the role of MEF2C in immunotherapy for GC., Methods: Transcriptome sequence data of GC was obtained from The Cancer Genome Atlas (TCGA), the Gene Expression Omnibus (GEO) and PRJEB25780 cohort for subsequent immune infiltration analysis, immune microenvironment analysis, consensus clustering analysis and feature selection for definition and classification of gene M and N. Principal component analysis (PCA) modeling was performed based on gene M and N for the calculation of immune checkpoint inhibitor (ICI) Score. Then, a Nomogram was constructed and evaluated for predicting the prognosis of GC patients, based on univariate and multivariate Cox regression. Functional enrichment analysis was performed to initially investigate the potential biological mechanisms. Through Genomics of Drug Sensitivity in Cancer (GDSC) dataset, the estimated IC 50 values of several chemotherapeutic drugs were calculated. Tumor-related transcription factors (TFs) were retrieved from the Cistrome Cancer database and utilized our model to screen these TFs, and weighted correlation network analysis (WGCNA) was performed to identify transcription factors strongly associated with immunotherapy in GC. Finally, 10 patients with advanced GC were enrolled from Sun Yat-sen University Cancer Center, including paired tumor tissues, paracancerous tissues and peritoneal metastases, for preparing sequencing library, in order to perform external validation., Results: Lower ICI Score was correlated with improved prognosis in both the training and validation cohorts. First, lower mutant-allele tumor heterogeneity (MATH) was associated with lower ICI Score, and those GC patients with lower MATH and lower ICI Score had the best prognosis. Second, regardless of the T or N staging, the low ICI Score group had significantly higher overall survival (OS) compared to the high ICI Score group. For its mechanisms, consistently, for Camptothecin, Doxorubicin, Mitomycin, Docetaxel, Cisplatin, Vinblastine, Sorafenib and Paclitaxel, all of the IC 50 values were significantly lower in the low ICI Score group compared to the high ICI Score group. As a result, based on univariate and multivariate Cox regression, ICI Score was considered to be an independent prognostic factor for GC. And our Nomogram showed good agreement between predicted and actual probabilities. Based on CIBERSORT deconvolution analysis, there was difference of immune cell composition found between high and low ICI Score groups, probably affecting the efficacy of immunotherapy. Then, MEF2C, a tumor-related transcription factor, was screened out by WGCNA analysis. Higher MEF2C expression is significantly correlated with a worse OS. Moreover, its higher expression is also negatively correlated with tumor mutation burden (TMB) and microsatellite instability (MSI), but positively correlated with several immunosuppressive molecules, indicating MEF2C may exert its influence on tumor development by upregulating immunosuppressive molecules. Finally, based on transcriptome sequencing data on 10 paired tumor tissues from Sun Yat-sen University Cancer Center, MEF2C expression was significantly lower in paracancerous tissues compared to tumor tissues and peritoneal metastases, and it was also lower in tumor tissues compared to peritoneal metastases, indicating a potential positive association between MEF2C expression and tumor invasiveness., Conclusions: Our prognostic model can effectively predict outcomes and facilitate stratification GC patients, offering valuable insights for clinical decision-making. The identified transcription factor MEF2C can serve as a biomarker for assessing the efficacy of immunotherapy for GC., Competing Interests: Declarations. Ethics approval and consent to participate: Prior to participation in this study, all patients provided informed consent for the use of their information and specimens for research purposes. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Purpose: To provide relative citation ratio (RCR) benchmark data for the field of glaucoma., Design: Cross-sectional bibliometric analysis., Subjects: Fellowship-trained glaucoma faculty at Accreditation Council for Graduate Medical Education-accredited institutions., Methods: Glaucoma faculty were individually indexed using the National Institutes of Health (NIH) iCite website. Publication count, mean RCR score, and weighted RCR score were collected for each author between May and August 2023 and included PubMed-listed articles from 1980 to 2023. Data were compared by sex, career duration, academic rank, and acquisition of a Doctor of Philosophy (PhD)., Main Outcome Measures: Total number of publications, mean RCR value, and weighted RCR value., Results: Five hundred twenty-six academic glaucoma specialists from 113 institutions were indexed. These physicians produced highly impactful research with a median publication count of 13 (interquartile range [IQR] 4-38), median RCR of 1.41 (IQR 0.97-1.98), and median weighted RCR of 16.89 (4.80-63.39). Academic rank, career duration, and having a PhD were associated with increased publication count, mean RCR, and weighted RCR. Publication count and weighted RCR differed significantly by sex; however, no difference was observed with mean RCR., Conclusions: Current academic glaucoma specialists have high mean RCR values relative to the NIH standard RCR value of 1. This benchmark data serve as a more accurate gauge of research impact within the glaucoma community and can be used to inform self, institutional, and departmental evaluations. Additionally, the mean RCR may provide an accurate metric for quantifying research productivity among historically underrepresented groups that are disadvantaged by time-dependent factors such as number of publications., Financial Disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article., (Copyright © 2024 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: The purpose of this study was to provide relative citation ratio (RCR) benchmark data for cornea and external diseases specialists., Design: This is a cross-sectional bibliometric analysis., Subjects: Subjects included were fellowship-trained cornea and external diseases faculty at Accreditation Council for Graduate Medical Education-accredited institutions in the United States., Methods: Academic specialists were indexed using the National Institutes of Health iCite Web site. Publication count, mean RCR score, and weighted RCR score were obtained between October 2022 and January 2023 by examining PubMed-listed publications from 1980 to 2022. Data were compared by sex, career duration, academic rank, and acquisition of a Doctor of Philosophy., Main Outcome Measures: The main outcome measures were publication count, mean RCR value, and weighted RCR value., Results: The cohort included 602 specialists from 112 Accreditation Council for Graduate Medical Education-accredited institutions. These clinician-scientists produced highly impactful research with a median publication count of 15 (interquartile ranges 4-41), median RCR of 1.4 (interquartile ranges 0.91-1.88), and median-weighted RCR of 20.28 (5.3-66.69). Both academic rank and career length were associated with greater publication count and RCR values. Male sex was also associated with greater publications counts and RCR scores compared with female faculty. Acquisition of a Doctor of Philosophy was associated with greater publication counts and weighted RCR scores but no difference in mean RCR scores., Conclusions: Academic cornea and external diseases specialists conduct high-impact research, with a median RCR of 1.4, exceeding the NIH standard value of 1. These data provide RCR benchmark data for the field to inform self, institutional, and departmental evaluations. These results also highlight a significant gender disparity in the field necessitating efforts to increase female representation and ensure equal opportunities., Competing Interests: The authors have no funding or conflicts of interest to disclose., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Anesthetic drugs used in labor analgesia also paralyze the bladder muscle by blocking the sacral plexus, thereby affecting maternal postpartum spontaneous urination and increasing the risk of postpartum urinary retention (PUR)., Aim: To analyze the effect of percutaneous electrical stimulation at the Baliao point combined with biofeedback therapy for PUR prevention., Methods: We selected 182 pregnant women who received labor analgesia in obstetrics between June 2022 and December 2023. They were divided into the combined therapy group (transcutaneous electrical stimulation of the Baliao point combined with biofeedback therapy) and the control group (biofeedback therapy alone). The first spontaneous urination time, first postpartum urine volume, bladder residual urine volume, postpartum hemorrhage volume, pre-urination waiting time, PUR incidence, adverse reactions, and the intervention's clinical efficacy were compared between the two groups., Results: The first spontaneous urination time after delivery was more delayed (2.92 ± 1.04 h vs 3.61 ± 1.13 h, P < 0.001), with fewer initial postpartum urine (163.54 ± 24.67 mL vs 143.72 ± 23.95 mL, P < 0.001), more residual bladder urine (54.81 ± 10.78 mL vs 65.25 ± 13.52 mL, P < 0.001), more postpartum bleeding (323.15 ± 46.95 mL vs 348.12 ± 45.03 mL, P = 0.001), and longer waiting time for urination (0.94 ± 0.31 min vs 1.29 ± 0.42 min, P < 0.001), in the control group than in the combined therapy group. The control group also had higher PUR incidence (4.65% vs 15.85%, P = 0.016). Both groups had no adverse reactions, but the clinical total efficacy rate of the intervention was significantly higher in the combined therapy group than in the control group (95.35% vs 84.15%, P = 0.016)., Conclusion: Percutaneous electrical stimulation of the Baliao point combined with biofeedback can significantly promote postpartum micturition of parturients with labor analgesia, thereby effectively preventing PUR occurrence., Competing Interests: Conflict-of-interest statement: There is no conflict of interest., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)

To explore the influence of perinatal-related factors on meconium aspiration syndrome (MAS) in full-term neonates and construct a nomogram prediction model for risk stratification of neonatal MAS and adoption of preventive measures. A total of 424 newborns and their mothers who were regularly examined at our hospital between January 2020 and December 2023 who had meconium-contaminated amniotic fluid during delivery were retrospectively selected as participants. Neonates were divided into MAS and non-MAS groups based on whether MAS occurred within 3 days after birth. Data from the 2 groups were analyzed, and factors influencing MAS were screened using multivariate logistic regression analysis. The R3.4.3 software was used to construct a nomogram prediction model for neonatal MAS risk. Receiver operating characteristic (ROC) curve analysis and the Hosmer-Lemeshow goodness-of-fit test were used to evaluate the performance of the model, and its clinical effectiveness was evaluated using a decision curve. Among the 424 neonates with meconium-stained amniotic fluid, 51 developed MAS within 3 days of birth (12.03%). Multivariate logistic regression analysis showed that a low amniotic fluid index before delivery (OR = 2.862, P = .019), advanced gestational age (OR = 0.526, P = .034), cesarean section (OR = 2.650, P = .013), severe amniotic fluid contamination (OR = 4.199, P = .002), low umbilical cord blood pH (OR = 2.938, P = .011), and low neonatal Apgar 1-min score (OR = 3.133, P = .006) were influencing factors of MAS in full-term neonates. Based on the above indicators, a nomogram prediction model for MAS risk of full-term newborns was constructed. The area under the ROC curve of the model was 0.931. The model was also tested for goodness-of-fit deviation (χ2 = 3.465, P = .903). Decision curve analysis found that the model was clinically effective in predicting the net benefit of MAS risk in neonates with meconium-stained amniotic fluid. The construction of a column chart prediction model for neonatal MAS risk based on prenatal amniotic fluid index, gestational age, delivery method, amniotic fluid contamination level, newborn umbilical blood pH value, and Apgar 1-min score has a certain application value., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Background: Improper opioid prescription after surgery is a well-documented iatrogenic contributor to the current opioid epidemic in North America. In fact, opioids are known to be overprescribed to liver transplant patients, and liver transplant patients with high doses or prolonged postsurgical opioid use have higher risks of graft failure and death., Methods: This is a retrospective cohort study of 552 opioid-naive patients undergoing liver transplant at an academic center between 2012 and 2019. The primary outcome was the discrepancy between the prescribed discharge opioid daily dose and each patient's own inpatient opioid consumption 24 h before discharge. Variables were analyzed with Wilcoxon and chi-square tests and logistic regression., Results: Opioids were overprescribed in 65.9% of patients, and 54.3% of patients who required no opioids the day before discharge were discharged with opioid prescriptions. In contrast, opioids were underprescribed in 13.4% of patients, among whom 27.0% consumed inpatient opioids but received no discharge opioid prescription. The median prescribed opioid daily dose was 333.3% and 56.3% of the median inpatient opioid daily dose in opioid overprescribed and underprescribed patients, respectively. Importantly, opioid underprescribed patients had higher rates of opioid refill 1 to 30 and 31 to 90 d after discharge, and the rate of opioid underprescription more than doubled from 2016 to 2019., Conclusions: Opioids are both over- and underprescribed to liver transplant patients, and opioid underprescribed patients had higher rates of opioid refill. Therefore, we proposed to prescribe discharge opioid prescriptions based on liver transplant patients' inpatient opioid consumption to provide patient-centered opioid prescriptions., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Abstract: Although postsurgical overprescription has been well-studied, postsurgical opioid underprescription remains largely overlooked. This retrospective cohort study was to investigate the extent of discharge opioid overprescription and underprescription in patients after neurological surgeries. Six thousand nine hundred forty-nine adult opioid-naive patients who underwent inpatient neurosurgical procedures at the University of California San Francisco were included. The primary outcome was the discrepancy between individual patient's prescribed daily oral morphine milligram equivalent (MME) at discharge and patient's own inpatient daily MME consumed within 24 hours of discharge. Analyses include Wilcoxon, Mann-Whitney, Kruskal-Wallis, and χ 2 tests, and linear or multivariable logistic regression. 64.3% and 19.5% of patients were opioid overprescribed and underprescribed, respectively, with median prescribed daily MME 360% and 55.2% of median inpatient daily MME in opioid overprescribed and underprescribed patients, respectively. 54.6% of patients with no inpatient opioid the day before discharge were opioid overprescribed. Opioid underprescription dose-dependently increased the rate of opioid refill 1 to 30 days after discharge. From 2016 to 2019, the percentage of patients with opioid overprescription decreased by 24.8%, but the percentage of patients with opioid underprescription increased by 51.2%. Thus, the mismatched discharge opioid prescription in patients after neurological surgeries presented as both opioid overprescription and underprescription, with a dose-dependent increased rate of opioid refill 1 to 30 days after discharge in opioid underprescription. Although we are fighting against opioid overprescription to postsurgical patients, we should not ignore postsurgical opioid underprescription., (Copyright © 2023 International Association for the Study of Pain.)

Background: Although postoperative opioid overprescription has been well studied, little is known about opioid underprescription. This study aims to determine the extent of improper discharge opioid prescription in patients undergoing general surgery procedures., Study Design: This retrospective cohort study investigated opioid-naïve adult patients who underwent inpatient general surgery at an academic medical center between June 2012 and December 2019. The primary outcome was the difference between individual patient's inpatient daily oral morphine milligram equivalent (MME) 24 hours before discharge and patient's prescribed daily MME at discharge. The data were analyzed using chi-square, Mann-Whitney, Wilcoxon, and Kruskal-Wallis tests and multivariable logistic regression., Results: Among 5,531 patients, 58.1% had opioid overprescription, and 22.4% had opioid underprescription. Median prescribed daily MME was 311% of median inpatient daily MME in overprescribed patients and 56.3% of median inpatient daily MME in underprescribed patients. About half (52.3%) of patients who consumed no opioids on the day before discharge were opioid overprescribed, and 69.9% of patients who required inpatient daily opioid of >100 MME were opioid underprescribed. Opioid-underprescribed patients had an increased opioid refill rate 1 to 30 days after discharge, whereas opioid-overprescribed patients had an increased refill rate 31 to 60 days after discharge. From 2017 to 2019, the percentage of overprescribed patients decreased by 35.8%, but the percentage of underprescribed patients increased by 42.4%., Conclusions: Although avoiding postoperative opioid overprescription remains imperative, preventing postoperative opioid underprescription is also essential. We recommend using a patient-centered approach to match the daily dose of opioid prescription with each patient's inpatient daily opioid consumption., (Copyright © 2023 by the American College of Surgeons. Published by Wolters Kluwer Health, Inc. All rights reserved.)

Introduction  Patients with chronic rhinitis suffer from postnasal drip (PND) but this symptom is not well addressed. Nasal endoscopy may aid in identifying PND. Well described endoscopic features of PND are presence of secretions in the posterior nasal cavity, diffuse erythema, and hemorrhagic spots in the nasopharynx, but these have not been formally studied. Objectives  The present study aims to assess the association of nasal endoscopic features with PND among rhinitis patients. This will guide clinicians to interpret the nasal endoscopic findings appropriately. Methods  Adults (≥ 18 years old) with chronic rhinitis were consecutively recruited at an Otorhinolaryngology outpatient clinic in a tertiary referral center. The patients were grouped into either "Rhinitis with PND" or "Rhinitis only." The endoscopic features of PND were scored as: Secretions in the posterior nasal cavity (yes/no), erythema in the nasopharynx (none, roof only, diffuse), hemorrhagic spots (yes/no), then were compared between groups. Results  There were 98 patients included (age 32.32 ± 11.33 years old, 61.2% female, 61.2% PND). Presence of secretions in the posterior nasal cavity was associated with PND ("Rhinitis with PND" versus "Rhinitis only," 78.3 versus 55.3; p  = 0.02; Odds ratio: 2.81; 95% confidence interval [CI]: 1.08-7.32). Diffuse erythema of the nasopharynx was more frequent in "rhinitis only" compared with those with PND (76.3 versus 53.3%; p  = 0.02). Hemorrhagic spots were equally present in both groups (11.7 versus 18.4%; p  = 0.35). Conclusion  Presence of secretions in the posterior nasal cavity may indicate bothersome PND among patients with rhinitis. Diffuse erythema of the nasopharynx and hemorrhagic spots are a nonspecific sign of inflammation., Competing Interests: Conflict of Interests The authors have no conflict of interests to declare., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution 4.0 International License, permitting copying and reproduction so long as the original work is given appropriate credit ( https://creativecommons.org/licenses/by/4.0/ ).)

Laryngeal tuberculosis is rare despite its close anatomical and physiological proximity to the lungs. It constitutes less than 1% of extrapulmonary tuberculosis. The symptoms of laryngeal tuberculosis are non-specific and mimic other laryngeal pathologies. The recent evolving and atypical endoscopic laryngeal features cause a diagnostic dilemma and delay in treatment. In this report, we presented three patients with distinct age and medical history, and hoarseness. Flexible videolaryngoscopy showed similar findings in the three cases, with irregular mucosa involving the entire length of the vocal fold, unilaterally in two cases and bilaterally in one. Mucosal waves were typically absent on laryngostroboscopy examination. The routine workup for pulmonary tuberculosis was unremarkable. The usage of Mycobacterium tuberculosis complex (MTBC) and rifampicin resistance (Xpert MTB/RIF) assay that detects Mycobacterium tuberculosis in the tissue biopsy specimens has helped in the rapid diagnosis of primary laryngeal tuberculosis and timely commencement of anti-tuberculous therapy. The clinical course and response to treatment were diverse in which two cases showed good response whilst the third developed disseminated tuberculosis despite optimal therapy., Competing Interests: Conflict of Interest: There is no conflict of interest to disclose., (©Copyright 2022 by Official Journal of the Turkish Society of Otorhinolaryngology and Head and Neck Surgery.)

Objective: To study the correlation between prognosis and status of the vestibule functions with the patients of the low frequency sudden deafness (SD). Method: Eighty-eight patients with low frequency SD were enrolled in this study, the cervical vestibular evoked myogenic potential (cVEMP), the ocular VEMP (oVEMP) and caloric test were evaluated. Based upon the results of the test, patients were divided into 4 groups. A group has no abnormal test results, B group has one abnormal test results, C group has two abnormal test results,and D group has three abnormal test results. Calculating and comparing the effective rate and uneffective rate were conducted in every group after treatment. Result: In A group, the effective rate is 27.27%, the uneffective rate is 2.27%. In B group, the effective rate is 36.36%, the uneffective rate is 4.55%.In C group, the effective rate is 9.09%, the uneffective rate is 6.82%. In D group, the effective rate is 0%, the uneffective rate is 13.64%. The difference between effective and uneffective rate was significant in group A, B, and D, while, there was no significant difference in group C. Conclusion: The prognosis of low frenquency SD patients without abnormal test results or only with one abnormal test results is good. While, the prognosis of patients with three abnormal test is bad. The prognosis of patients with two abnormal test is not sure. The vestibule functions test can be used to determine the prognosis of low frequency SD in clinical treatment., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Post-synaptic density protein 95 (PSD-95) links neuronal nitric oxide synthase (nNOS) with the N-methyl-D-aspartic acid (NMDA) receptor in the central nervous system, and this molecular complex has been implicated in regulating neuronal excitability in several neurological disorders. Here, small-molecule inhibitors of the PSD-95/nNOS interaction, IC87201 and ZL006 were tested for neuroprotective effects in an in vitro Parkinson's disease (PD) model. We now report that IC87201 and ZL006 reduced MPP(+)-induced neuronal injury and apoptotic cell death in a dose-dependent manner in cultured cortical neurons. These protective effects were associated with suppressed mitochondrial dysfunction, as evidenced by decreased reactive oxygen species (ROS) generation, cytochrome c release, mitochondrial membrane potential (MMP) collapse, and the preserved mitochondrial complex I activity and ATP synthesis. IC87201 and ZL006 also preserved intracellular homeostasis through mitigating mitochondrial Ca(2+) uptake and promoting mitochondrial Ca(2+) buffering capacity. Moreover, treatment with IC87201 and ZL006 significantly increased the expression of Sirt3 after MPP(+) exposure, and knockdown of Sirt3 using specific targeted small interfere RNA (siRNA) partially nullified the protective effects induced by these two inhibitors. These data strongly support the hypothesis that targeting the PSD-95/nNOS interaction produces neuroprotective effects and may represent a novel class of therapeutics for PD as well as other neurological diseases where detrimental NMDA receptor signaling plays a major role., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The Wilms' tumor suppressor gene, wt1, encodes a zinc-finger protein, WT1, that functions as a potent inhibitor of cell growth. The findings that expression levels of WT1 were down-regulated in breast cancer cell lines and in subsets of primary breast tumors led us to investigate the possible role of WT1 in tumorigenesis of breast cancer. We have established stable cell lines from a breast cancer cell line MDA-MB-231 to express exogenous WT1, and investigated the ability of WT1 to inhibit the transformed phenotype of MDA-MB-231 cells. We found that WT1 suppressed clonal growth of MDA-MB-231 cells in soft-agar and inhibited tumor growth of these cells in nude mice. We also found that the steady state levels of beta-catenin protein and the transcription activity of beta-catenin/Tcf signaling pathway were dramatically decreased in WT1-transfected cells. This decrease of beta-catenin was associated with increased levels of beta-catenin phosphorylation. Furthermore, the expression levels of GSK-3 beta, the kinase that phosphorylates beta-catenin and signals its degradation, were up-regulated in WT1-transfected cells. The results suggest that WT1 inhibits the transformed phenotype of breast cancer cells and down-regulates the beta-catenin/TCF signaling pathway through destabilization of beta-catenin.

We have found previously that the retinoblastoma (Rb) suppressor associated protein 46 (RbAp46) is a gene upregulated by the Wilms' tumor suppressor, WT1, and functions as a potent growth inhibitor. To investigate the effect of RbAp46 overexpression on early development of breast cancer, we established stable cell lines from neoplastigenic breast epithelial cells, MCF10AT3B, a cell line derived from a model of human proliferative disease, to constitutively express exogenous RbAp46. We have found that expression of RbAp46 suppressed colony formation of MCF10AT3B cells in soft-agar, and inhibited tumor formation of these cells in nude mice. Expression of RbAp46 sensitized MCF10AT3B cells to apoptosis induced by serum deprivation and hydrocortisone withdrawal. Furthermore, we have found that the c-Jun NH2-terminal kinase (JNK) pathway and GADD45, a growth arrest- and DNA damage-inducible gene, are constitutively activated in RbAp46-expressing cells. Our data suggested that high levels of RbAp46 expression inhibit the tumorigenicity of neoplastigenic breast epithelial cells by facilitating JNK-dependent apoptotic cell death. Our data also suggested that dysregulation of RbAp46 gene may be involved in the early development of breast cancer., (Copyright 2003 Wiley-Liss, Inc.)

When estrogen binds its receptor (ER), it becomes a potent mitogen in a number of target tissues including the mammary gland where it plays an important role in the pathogenesis of mammary carcinoma. Arsenic trioxide (AS2O3), a clinically effective agent against acute promyelocytic leukemia, has been shown to induce apoptosis in a variety of cancer cells in vitro. Here, we investigated the effects of AS2O3 on the growth of two ER-positive breast cancer cell lines, MCF7 and T47D in vitro. We found that higher doses of AS2O3 dramatically reduced the survival of these two breast cancer cell lines while lower doses of AS2O3 significantly inhibited the expression of estrogen receptor alpha (ER-alpha), but did not effect ER-beta expression. The ER-alpha expression is totally restored when AS2O3 is absent for 24 hours. Using a reporter gene controlled by ER, we further demonstrated that AS2O3 strongly-repressed 17beta-estradiol (E2) stimulated-transcriptional activation. Moreover, AS2O3 abolished transcriptional induction of the estrogen responsive gene pS2 mediated by E2. These results indicated that AS2O3 specifically inhibits expression and signaling pathway of the ER-alpha. We suggest that AS2O3 in combination with other methods might provide a novel therapeutic approach for ER-alpha-positive breast cancer.

The retinoblastoma suppressor (Rb)-associated protein 46 (RbAp46) is a nuclear protein of the WD-repeat protein family and a component of the histone deacetylase complex that physically interacts with Rb. We demonstrated that RbAp46 is a gene up-regulated by the Wilms' tumor suppressor (WT1) and functions as a negative regulator of cell growth. Here we have investigated the ability of RbAp46 to inhibit malignant phenotype of adenovirus-transformed human embryonic kidney (HEK) 293 cells in tumorigenesis assays. We have found that expression of RbAp46 suppressed clonal growth of HEK 293 cells in soft agar and inhibited tumor growth of these cells in nude mice. Furthermore, expression of RbAp46 resulted in an increase of cells in the G2/M fraction of cell cycle and augmented apoptosis in serum-starved cells. The results suggest that high levels of RbAp46 expression inhibit the transformation of tumor cells through interfering with normal cell cycle and/or enhancing apoptotic cell death., (Copyright 2001 Wiley-Liss, Inc.)

The retinoblastoma suppressor (Rb)-associated protein 46 (RbAp46) is a member of the WD-repeat protein family and a component of the histone modifying and remodeling complexes. Previously, we demonstrated that RbAp46 is a potent growth inhibitor that can suppress the transformed phenotype of tumor cells. To explore the molecular mechanisms of RbAp46 function, we used RbAp46 as a bait in a yeast two-hybrid screening and found that RbAp46 interacts specifically with the C-terminal region of BRCA1 (the BRCT domain), a domain involved in the t transactivation activity of BRCA1. Coimmunoprecipitation assays demonstrated that the interaction of RbAp46 with BRCA1 requires the first two of the four Trp-Asp (WD)-repeats of RbAp46. We also showed that expression of RbAp46 represses the transactivation activity mediated by the BRCT/Gal4 fusion protein and inhibits the transactivation of the p21 promoter mediated by the full-length BRCA1. Interestingly, the association of BRCA1 and RbAp46 is disrupted in cells treated with DNA-damaging agents. These results suggest that RbAp46 may specifically interact with BRCA1 and modulate its transactivation activity in response to DNA damage., (Copyright 2001 Academic Press.)

Wilms' tumor is associated with mutations of WT1, a zinc-finger transcription factor that is essential for the development of the metanephric kidney and the urogenital system. High levels of WT1 expression also have been detected in myeloid leukemia cells, suggesting that WT1 may be important in other neoplasms as well. To seek a role of high level expression of WT1 in the differential arrest characteristic of myeloid leukemia, WT1 or its zinc-finger domain alone was stably expressed in human promyeloid leukemia (HL-60) cells and the ability of 12-O-tetradecanoyl-phorbol-13-acetate (TPA) to induce macrophage differentiation was examined. HL-60 cell differentiation was completely arrested in TPA treated cells that expressed WT1 or its zinc-finger domain alone whereas TPA fully induced macrophage differentiation in control HL-60 cells, indicating that high level expression of WT1 is capable of differentiation arrest of myeloid cells and that its effect may be mediated through its zinc-finger domain. To determine if the zinc-finger domain of WT1 directly influences transcription, it was brought to promoter DNA as a fusion protein with the Gal4 DNA binding domain. The fusion protein failed to regulate transcription of a reporter gene but when the zinc-finger domain of WT1 was brought to DNA with a promoter containing two upstream WT1-binding sites, reporter gene expression was activated approximately threefold, suggesting that WT1 interferes with myeloid differentiation through the ability of its zinc-finger domain to compete with other transcription factors for common promoter elements., (Copyright 1999 Academic Press.)

The Wilms' tumor suppressor gene, wt1, encodes a zinc-finger transcription factor, WT1, that plays an important role in controlling urogenital development. Previously, WT1 has been shown to inhibit cell growth and to repress transcription initiated from the promoters of a number of growth-promoting genes. However, few physiological target genes that are transcriptionally activated by WT1 have been established. Using suppression subtractive hybridization polymerase chain reaction, we isolated a WT1 target gene that is up-regulated about 15-fold in cells expressing WT1. The gene was identified as retinoblastoma suppressor (Rb)-associated protein 46 (RbAp46), a nuclear protein that interacts physically with Rb and is a component of the human mSin3 co-repressor complex. Cells transfected with RbAp46 cDNA formed fewer colonies than the control cells, and RbAp46 suppressed the growth rate (by about 2-fold) of transfected cells. In the developing kidney and gonad, RbAp46 exhibits an expression pattern similar to that of WT1. We conclude that RbAp46 has strong growth inhibition activity and may function as an important mediator of WT1's function.

The Wilms' tumor suppressor gene, wt1, encodes a zinc-finger transcription factor, WT1, that represses transcription of a number of growth-promoting genes and inhibits cell growth. The transcripts of wt1 undergo two alternative splicing events, giving rise to four isoforms of mRNA in constant ratios. The first alternative splice introduces an extra exon 5, which encodes 17 amino acid residues inserted between the transcription regulatory domain and the DNA binding domain of WT1. Previously, we demonstrated that the 17-amino acid domain functioned as a transcription repressor when it was fused with the DNA binding domain of WT1. We have now identified a point mutation within exon 5 of wt1 in a sporadic unilateral Wilms' tumor patient. The mutation changes the last of the 17 amino acids from asparagine to serine. The protein isoform of WT1 carrying this mutation exhibited a 2-3-fold lower transcription-repressing activity than wild-type WT1 in transient cotransfection assays. The mutation also decreased growth-inhibiting activity of WT1 in two osteosarcoma cell lines, U2OS and Saos-2. By diminishing transcription-repressing and growth-inhibiting activities of WT1, this naturally occurring mutation within exon 5 of wt1 may disturb the normal function of the protein and lead to the uncontrolled cell growth characteristic of Wilms' tumor.