Breast cancer stem cells (BCSC) are resistant to conventional chemotherapy and radiotherapy, which may destroy tumor masses but not all BCSC that can mediate relapses. In the present study, we showed ...that the level of Wnt/β-catenin signaling in BCSC is relatively higher than in bulk tumor cells, contributing to a relatively higher level of therapeutic resistance. We designed a highly potent small-molecule inhibitor, CWP232228, which antagonizes binding of β-catenin to T-cell factor (TCF) in the nucleus. Notably, although CWP232228 inhibited the growth of both BCSC and bulk tumor cells by inhibiting β-catenin-mediated transcription, BCSC exhibited greater growth inhibition than bulk tumor cells. We also documented evidence of greater insulin-like growth factor-I (IGF-I) expression by BCSC than by bulk tumor cells and that CWP232228 attenuated IGF-I-mediated BCSC functions. These results suggested that the inhibitory effect of CWP232228 on BCSC growth might be achieved through the disruption of IGF-I activity. Taken together, our findings indicate that CWP232228 offers a candidate therapeutic agent for breast cancer that preferentially targets BCSC as well as bulk tumor cells.
High dysadherin expression has been recognized as a biological predictor of metastasis and poor prognosis for many different cancer types; however, the molecular mechanisms of how dysadherin affects ...cancer progression are still poorly understood. In this study, we examined whether AKT signaling could link dysadherin expression with downstream events that promote the metastatic potential of human breast cancer cells. Immunohistochemical analysis of breast cancer tissues showed that dysadherin expression was highly associated with elevated expression of phospho‐AKT. The introduction of dysadherin cDNA into BT‐474, MCF‐7 and T‐47D breast cancer cell lines enhanced their levels of AKT phosphorylation, while knockdown of dysadherin in MDA‐MB‐231 and Hs578T breast cancer cell lines suppressed AKT phosphorylation. Treatment with the AKT inhibitor triciribine suppressed dysadherin‐mediated pro‐metastatic effects, including epithelial–mesenchymal transition, cell motility and drug resistance. These findings suggest that dysadherin might contribute to breast cancer progression through AKT activation. (Cancer Sci 2012; 103: 1280–1289)
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The development of premalignant colorectal polyps is significantly influenced by various lifestyle and modifiable risk factors. In our study, we used a large cohort of 9025 patients, who underwent ...screening colonoscopies at a university hospital, to assess the risk factors associated with the development of three different colorectal cancer precursor lesions: non-advanced adenomas (NAs), advanced adenomatous lesions (ADLs), and sessile serrated lesions (SSLs). Among the participants, 3641 had NAs, 836 had ADLs, and 533 had SSLs. We identified obesity, current smoking, and appendicular skeletal muscle mass as modifiable lifestyle risk factors that increase the development of NAs and ADLs (all P < 0.05). Furthermore, we found a positive correlation between the degree of obesity and an increased risk of developing NAs and ADLs (all P for trend < 0.001), while non-smoking was associated with a decreased risk (P for trend < 0.001 and 0.003, respectively). Smoking was the only modifiable risk factor for developing SSLs (adjusted odds ratio aOR 1.58; 95% confidence interval CI 1.20–2.07), and the risk was even higher in patients with metabolic syndrome (aOR 1.71; 95% CI 1.05–2.77). Addressing modifiable lifestyle factors such as smoking and obesity could play an important role in reducing the risk of both non-advanced and advanced adenomatous lesions. Smoking cessation is especially important as it is a significant modifiable risk factor for sessile serrated lesions.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Abstract
Homologous recombination (HR) is critical for error-free repair of DNA double-strand breaks. Chromatin loading of RAD51, a key protein that mediates the recombination, is a crucial step in ...the execution of the HR repair. Here, we present evidence that SUMOylation of RAD51 is crucial for the RAD51 recruitment to chromatin and HR repair. We found that topoisomerase 1-binding arginine/serine-rich protein (TOPORS) induces the SUMOylation of RAD51 at lysine residues 57 and 70 in response to DNA damaging agents. The SUMOylation was facilitated by an ATM-induced phosphorylation of TOPORS at threonine 515 upon DNA damage. Knockdown of TOPORS or expression of SUMOylation-deficient RAD51 mutants caused reduction in supporting normal RAD51 functions during the HR repair, suggesting the physiological importance of the modification. We found that the SUMOylation-deficient RAD51 reduces the association with its crucial binding partner BRCA2, explaining its deficiency in supporting the HR repair. These findings altogether demonstrate a crucial role for TOPORS-mediated RAD51 SUMOylation in promoting HR repair and genomic maintenance.
High aldehyde dehydrogenase (ALDH) activity has been recognized as a marker of cancer stem cells (CSCs) in breast cancer. In this study, we examined whether inhibition of ALDH activity suppresses ...stem-like cell properties in a 4T1 syngeneic mouse model of breast cancer. We found that ALDH-positive 4T1 cells showed stem cell-like properties in vitro and in vivo. Blockade of ALDH activity reduced the growth of CSCs in breast cancer cell lines. Treatment of mice with the ALDH inhibitor diethylaminobenzaldehyde (DEAB) significantly suppressed 4T1 cell metastasis to the lung. Recent evidence suggests that ALDH affects the response of stem cells to hypoxia; therefore, we examined a possible link between ALDH and hypoxia signaling in breast cancer. Hypoxia-inducible factor-2α (HIF-2α) was highly dysregulated in ALDH-positive 4T1 cells. We observed that ALDH was highly correlated with the HIF-2α expression in breast cancer cell lines and tissues. DEAB treatment of breast cancer cells reduced the expression of HIF-2αin vitro. In addition, reduction of HIF-2α expression suppressed in vitro self-renewal ability and in vivo tumor initiation in ALDH-positive 4T1 cells. Therefore, our findings may provide the evidence necessary for exploring a new strategy in the treatment of breast cancer.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Ischaemic stroke is a leading cause of death and long-lasting disability. Gastrodia elata blume (GEB) is a Chinese herb that is widely used to treat convulsive disorders, such as epilepsy, and ...p-hydroxybenzyl alcohol (HBA) is the active ingredient in GEB. The present study was conducted to evaluate the effects of GEB and HBA on the brain damage and transcriptional levels of Protein disulfide isomerase (PDI) and 1-Cys peroxiredoxin (1-Cys Prx) genes known to play a role in antioxidant systems after transient focal ischemia in the rat brain. Focal ischemia was induced in rats by middle cerebral artery occlusion (MCAO). All animals underwent ischemia for 1 h, followed by 24 h of reperfusion. Coronal brain slices were stained with 2,3,5-triphenyltetrazolium chloride or total RNA was extracted for the analysis of gene expression. Histopathologic analysis revealed a significant (p<0.05) decrease in infarct size in the ipsilateral brain with GEB extracts or HBA. Moreover, the levels of PDI and 1-Cys Prx transcription were significantly increased in the GEB extract- or HBA-treated group compared with the untreated group (p<0.05). This study therefore indicated that GEB and HBA provide neuroprotection by preventing brain damage through the increased expression of genes encoding antioxidant proteins after transient focal cerebral ischemia and may be effective as neuroprotective agents at the cellular and molecular levels in the brain.
The compounds 1,8-cineole and zerumbone (ZER) from the Cyperus rotundus rhizome along with another 11 previously identified rhizome essential oil constituents and α-humulene, which lacks the only ...carbonyl group present in ZER, as well as binary mixtures of ZER and seven active compounds were tested for repellency to male B. germanica. The results were compared to N,N-diethyl-3-methylbenzamide (deet). In filter-paper choice tests, ZER was the most repellent compound, and α-humulene was ineffective, which indicates that the α,β-unsaturated carbonyl group of ZER is a prerequisite component for repellency. At 81.5 μg cm
, enhanced repellency was produced by binary mixtures of ZER and 1,8-cineole, (+)-dihydrocarvone or (R)-(+)-limonene (70:30, 50:50 and 30:70 ratios by weight). These mixtures were very effective against male B. germanica within 24 h and were more repellent than a single compound or deet alone. The optimum ZER content was determined to be more than 50%. In Ebeling choice box tests at 652.4 μg cm
, these compounds and deet resulted in complete repellency to intact male B. germanica, while they exhibited 35-47% repellency to antennectomized male one. Mixtures formulated from the active constituents of the C. rotundus rhizome could be useful as potential repellents for controlling B. germanica.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Background/Aims: Acute upper gastrointestinal (UGI) bleeding is a significant emergency situation with a mortality rate of 2% to 10%. Therefore, initial risk stratification is important for proper ...management. We aimed to evaluate the role of contrast-enhanced multidetector computed tomography (MDCT) for risk stratification in patients with acute UGI bleeding in the emergency room (ER).Methods: This retrospective study included patients with UGI bleeding in the ER. Glasgow-Blatchford risk score-computed tomography (GBS-CT) was assessed using a combination of GBS and the MDCT scan scoring system.Results: Of the 297 patients with UGI bleeding, 124 (41.8%) underwent abdominal MDCT. Among them, 90.3% were classified as high-risk by GBS, and five patients died (4.0%). Rebleeding occurred in nine patients (7.3%). The high-risk GBS-CT group had significantly higher in-hospital mortality (10.5% in high-risk vs. 1.4% in moderate risk vs. 0% in low-risk, p = 0.049), transfusion amount (p < 0.001), and endoscopic hemostasis (p < 0.001) compared to the moderate- and low-risk groups.Conclusions: Adding MDCT scans to the existing validated prognosis model when predicting the risk of UGI bleeding in patients in the ER plays a significant role in determining in-hospital mortality, transfusions, and the need for endoscopic hemostasis.
Inherited prion diseases (IPDs), including genetic Creutzfeldt-Jakob disease (gCJD), account for 10-15% of cases of prion diseases and are associated with several pathogenic mutations, including ...P102L, V180I, and E200K, in the prion protein gene (PRNP). The valine to isoleucine substitution at codon 180 (V180I) of PRNP is the most common pathogenic mutation causing gCJD in East Asian patients. In this study, we conducted follow-up analyses to identify candidate factors and their associations with disease onset. Whole-genome sequencing (WGS) data of five gCJD patients with V180I mutation and 145 healthy individuals were used to identify genomic differences. A total of 18,648,850 candidate variants were observed in only the patient group, 29 of them were validated as variants. Four of these validated variants were nonsense mutations, six were observed in genes directly or indirectly related to neurodegenerative disorders (NDs), such as LPA, LRRK2, and FGF20. More than half of validated variants were categorized in Gene Ontology (GO) terms of binding and/or catalytic activity. Moreover, we found differential genome variants in gCJD patients with V180I mutation, including one uniquely surviving 10 years after diagnosis of the disease. Elucidation of the relationships between gCJD and Alzheimer's disease or Parkinson's disease at the genomic level will facilitate further advances in our understanding of the specific mechanisms mediating the pathogenesis of NDs and gold standard therapies for NDs.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The use of endoscopic images for the accurate assessment of ulcerative colitis (UC) severity is crucial to determining appropriate treatment. However, experts may interpret these images differently, ...leading to inconsistent diagnoses. This study aims to address the issue by introducing a standardization method based on deep learning. We collected 254 rectal endoscopic images from 115 patients with UC, and five experts in endoscopic image interpretation assigned classification labels based on the Ulcerative Colitis Endoscopic Index of Severity (UCEIS) scoring system. Interobserver variance analysis of the five experts yielded an intraclass correlation coefficient of 0.8431 for UCEIS scores and a kappa coefficient of 0.4916 when the UCEIS scores were transformed into UC severity measures. To establish a consensus, we created a model that considered only the images and labels on which more than half of the experts agreed. This consensus model achieved an accuracy of 0.94 when tested with 50 images. Compared with models trained from individual expert labels, the consensus model demonstrated the most reliable prediction results.