Publications by authors named "Hao-Chen Wang"

21 Publications

  • Page 1 of 1

Local ablation of gastric cancer by reconstituted apolipoprotein B lipoparticles carrying epigenetic drugs.

Nanomedicine 2021 10 29;37:102450. Epub 2021 Jul 29.

Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan. Electronic address:

Epigenetic inhibitors have shown anticancer effects. Combination chemotherapy with epigenetic inhibitors has shown high effectiveness in gastric cancer clinical trials, but severe side effect and local progression are the causes of treatment failure. Therefore, we sought to develop an acidity-sensitive drug delivery system to release drugs locally to diminish unfavorable outcome of gastric cancer. In this study, we showed that, as compared with single agents, combination treatment with the demethylating agent 5'-aza-2'-deoxycytidine and HDAC inhibitors Trichostatin A or LBH589 decreased cell survival, blocked cell cycle by reducing number of S-phase cells and expression of cyclins, increased cell apoptosis by inducing expression of Bim and cleaved Caspase 3, and reexpressed tumor suppressor genes more effectively in MGCC3I cells. As a carrier, reconstituted apolipoprotein B lipoparticles (rABLs) could release drugs in acidic environments. Orally administrated embedded drugs not only showed inhibitory effects on gastric tumor growth in a syngeneic orthotopic mouse model, but also reduced the hepatic and renal toxicity. In conclusion, we have established rABL-based nanoparticles embedded epigenetic inhibitors for local treatment of gastric cancer, which have good therapeutic effects but do not cause severe side effects.
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http://dx.doi.org/10.1016/j.nano.2021.102450DOI Listing
October 2021

Epigenetic silencing of AATK in acinar to ductal metaplasia in murine model of pancreatic cancer.

Clin Epigenetics 2020 06 17;12(1):87. Epub 2020 Jun 17.

Department of Biochemistry and Molecular Biology, College of Medicine, National Cheng Kung University, Tainan, Taiwan.

Background: Cancer subtype switching, which involves unclear cancer cell origin, cell fate decision, and transdifferentiation of cells within a confined tumor microenvironment, remains a major problem in pancreatic cancer (PDA).

Results: By analyzing PDA subtypes in The Cancer Genome Atlas, we identified that epigenetic silencing of apoptosis-associated tyrosine kinase (AATK) inversely was correlated with mRNA expression and was enriched in the quasi-mesenchymal cancer subtype. By comparing early mouse pancreatic lesions, the non-invasive regions showed AATK co-expression in cells with acinar-to-ductal metaplasia, nuclear VAV1 localization, and cell cycle suppression; but the invasive lesions conversely revealed diminished AATK expression in those with poorly differentiated histology, cytosolic VAV1 localization, and co-expression of p63 and HNF1α. Transiently activated AATK initiates acinar differentiation into a ductal cell fate to establish apical-basal polarization in acinar-to-ductal metaplasia. Silenced AATK and ectopically expressed p63 and HNF1α allow the proliferation of ductal PanINs in mice.

Conclusion: Epigenetic silencing of AATK regulates the cellular transdifferentiation, proliferation, and cell cycle progression in converting PDA-subtypes.
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http://dx.doi.org/10.1186/s13148-020-00878-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7301993PMC
June 2020

Pancreatic stellate cells activated by mutant KRAS-mediated PAI-1 upregulation foster pancreatic cancer progression via IL-8.

Theranostics 2019 23;9(24):7168-7183. Epub 2019 Sep 23.

Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.

The dense fibrotic stroma enveloping pancreatic tumors is a major cause of drug resistance. Pancreatic stellate cells (PSCs) in the stroma can be activated to induce intra-tumor fibrosis and worsen patient survival; however, the molecular basics for the regulation of PSC activation remains unclear. The coculture system was used to study cancer cell-PSC interactions. Atomic force microscopy was used to measure the stiffness of tumor tissues and coculture gels. Cytokine arrays, qPCR, and Western blotting were performed to identify the potential factors involved in PSC activation and to elucidate underlying pathways. PSC activation characterized by α-SMA expression was associated with increased pancreatic tumor stiffness and poor prognosis. Coculture with cancer cells induced PSC activation, which increased organotypic coculture gel stiffness and cancer cell invasion. Cancer cells-derived PAI-1 identified from coculture medium could activate PSCs, consistent with pancreatic cancer tissue microarray analysis showing a strong positive correlation between PAI-1 and α-SMA expression. Suppression by knocking down PAI-1 in cancer cells demonstrated the requirement of PAI-1 for coculture-induced PSC activation and gel stiffness. PAI-1 could be upregulated by KRAS in pancreatic cancer cells through ERK. In PSCs, inhibition of LRP-1, ERK, and c-JUN neutralized the effect of PAI-1, suggesting the contribution of LRP-1/ERK/c-JUN signaling. Furthermore, activated PSCs might exacerbate malignant behavior of cancer cells via IL-8 because suppression of IL-8 signaling reduced pancreatic tumor growth and fibrosis . KRAS-mutant pancreatic cancer cells can activate PSCs through PAI-1/LRP-1 signaling to promote fibrosis and cancer progression.
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http://dx.doi.org/10.7150/thno.36830DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6831292PMC
September 2020

Low CD8⁺ T Cell Infiltration and High PD-L1 Expression Are Associated with Level of CD44⁺/CD133⁺ Cancer Stem Cells and Predict an Unfavorable Prognosis in Pancreatic Cancer.

Cancers (Basel) 2019 Apr 15;11(4). Epub 2019 Apr 15.

Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan.

Cancer immunotherapy targeting immune checkpoints has exhibited promising clinical outcomes in many cancers, but it offers only limited benefits for pancreatic cancer (PC). Cancer stem cells (CSCs), a minor subpopulation of cancer cells, play important roles in tumor initiation, progression, and drug resistance. Accumulating evidence suggests that CSCs employ immunosuppressive effects to evade immune system recognition. However, the clinical implications of the associations among CD8⁺ T cells infiltration, programmed death receptor ligand-1 (PD-L1) expression, and CSCs existence are poorly understood in PC. Immunostaining and quantitative analysis were performed to assess CD8⁺ T cells infiltration, PD-L1 expression, and their relationship with CD44⁺/CD133⁺ CSCs and disease progression in PC. CD8⁺ T cells infiltration was associated with better survival while PD-L1 expression was correlated with PC recurrence. Both the low CD8⁺ T cells infiltration/high PD-L1 expression group and the high CD8⁺ T cells infiltration/high PD-L1 expression group show high levels of CD44⁺/CD133⁺ CSCs, but patients with low CD8⁺ T cells infiltration/high PD-L1 expression had worse survival and higher recurrence risk than those with high CD8⁺ T cells infiltration/high PD-L1 expression. Moreover, high infiltration of CD8⁺ T cells could reduce unfavorable prognostic effect of high co-expression of PD-L1 and CD44/CD133. Our study highlights an interaction among CD8⁺ T cells infiltration, PD-L1 expression, and CD44⁺/CD133⁺ CSCs existence, which contributes to PC progression and immune evasion.
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http://dx.doi.org/10.3390/cancers11040541DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6520688PMC
April 2019

Salubrinal offers neuroprotection through suppressing endoplasmic reticulum stress, autophagy and apoptosis in a mouse traumatic brain injury model.

Neurobiol Learn Mem 2019 05 6;161:12-25. Epub 2019 Mar 6.

Department of Forensic Medicine, Medical School of Soochow University, Suzhou 215123, China. Electronic address:

Traumatic brain injury (TBI) is a complex injury that can cause severe disabilities and even death. TBI can induce secondary injury cascades, including but not limited to endoplasmic reticulum (ER) stress, apoptosis and autophagy. Although the investigators has previously shown that salubrinal, the selective phosphatase inhibitor of p-eIF2α, ameliorated neurologic deficits in murine TBI model, the neuroprotective mechanisms of salubrinal need further research to warrant the preclinical value. This study was undertaken to characterize the effects of salubrinal on cell death and neurological outcomes following TBI in mice and the potential mechanisms. In the current study, ER stress-related proteins including p-eIF2α, GRP78 and CHOP showed peak expressions both in the cortex and hippocampus from day 2 to day 3 after TBI, indicating ER stress was activated in our TBI model. Immunofluorescence staining showed that CHOP co-located NeuN-positive neuron, GFAP-positive astrocyte, Iba-1-positive microglia, CD31-positive vascular endothelial cell and PDGFR-β-positive pericyte in the cortex on day 2 after TBI, and these cells mentioned above constitute the neurovascular unit (NVU). We also found TBI-induced plasmalemma permeability, motor dysfunction, spatial learning and memory deficits and brain lesion volume were alleviated by continuous intraperitoneal administration of salubrinal post TBI. To investigate the underlying mechanisms further, we determined that salubrinal suppressed the expression of ER stress, autophagy and apoptosis related proteins on day 2 after TBI. In addition, salubrinal administration decreased the number of CHOP+/TUNEL+ and CHOP+/LC3+ cells on day 2 after TBI, detected by immunofluorescence. In conclusion, these data imply that salubrinal treatment improves morphological and functional outcomes caused by TBI in mice and these neuroprotective effects may be associated with inhibiting apoptosis, at least in part by suppressing ER stress-autophagy pathway.
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http://dx.doi.org/10.1016/j.nlm.2019.03.002DOI Listing
May 2019

Elevated Serum Interleukin-8 Level Correlates with Cancer-Related Cachexia and Sarcopenia: An Indicator for Pancreatic Cancer Outcomes.

J Clin Med 2018 Dec 1;7(12). Epub 2018 Dec 1.

Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan 704, Taiwan.

Cancer cachexia (CC), characterized by body weight loss and sarcopenia, contributes to over 20% of all cancer-related death. Approximately 80% of pancreatic cancer (PC) patients develop CC during disease progression. Pro-inflammatory cytokines, including interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor (TNF)-α, have been correlated with CC; however, its prognostic significance remains unclear. In this study, serum levels of the CC-related cytokines were determined in normal donors and PC patients. IL-8 expression was assessed in PC tissue microarrays. The correlation of levels of each cytokine with disease progression, weight loss, and sarcopenia was calculated. The relationships among the baseline variables, CC, and IL-8 expression with disease progression were examined using univariate and multivariate analyses. Of these mentioned cytokines, only serum IL-8 level was elevated in the locally advanced group ( = 55) compared with the normal ( = 17) and resected groups ( = 55). Serum IL-8 level was positively correlated with CC status, weight loss, sarcopenia, but was negatively correlated with total psoas area (TPA). IL-8 expression in tissue samples was also positively associated with weight loss. Furthermore, serum IL-8 level was an independent predictor of survival. In conclusion, elevated serum IL-8 level significantly correlates with CC and sarcopenia and can be used as a prognostic indicator in PC.
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http://dx.doi.org/10.3390/jcm7120502DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6306800PMC
December 2018

IL-33/ST2L Signaling Provides Neuroprotection Through Inhibiting Autophagy, Endoplasmic Reticulum Stress, and Apoptosis in a Mouse Model of Traumatic Brain Injury.

Front Cell Neurosci 2018 25;12:95. Epub 2018 Apr 25.

Department of Forensic Science, Medical School of Soochow University, Suzhou, China.

Interleukin-33 (IL-33) is a member of the interleukin-1 (IL-1) cytokine family and an extracellular ligand for the orphan IL-1 receptor ST2. Accumulated evidence shows that the IL-33/ST2 axis plays a crucial role in the pathogenesis of central nervous system (CNS) diseases and injury, including traumatic brain injury (TBI). However, the roles and molecular mechanisms of the IL-33/ST2 axis after TBI remain poorly understood. In this study, we investigated the role of IL-33/ST2 signaling in mouse TBI-induced brain edema and neurobehavioral deficits, and further exploited underlying mechanisms, using salubrinal (SAL), the endoplasmic reticulum (ER) stress inhibitor and anti-ST2L. The increase in IL-33 level and the decrease in ST2L level at injured cortex were first observed at 24 h post-TBI. By immunofluorescent double-labeled staining, IL-33 co-localized in GFAP-positive astrocytes, and Olig-2-positive oligodendrocytes, and predominantly presented in their nucleus. Additionally, TBI-induced brain water content, motor function outcome, and spatial learning and memory deficits were alleviated by IL-33 treatment. Moreover, IL-33 and SAL alone, or their combination prevented TBI-induced the increase of IL-1β and TNF-α levels, suppressed the up-regulation of ER stress, apoptosis and autophagy after TBI. However, anti-ST2L treatment could significantly invert the above effects of IL-33. Together, these data demonstrate that IL-33/ST2 signaling mitigates TBI-induced brain edema, motor function outcome, spatial learning and memory deficits, at least in part, by a mechanism involving suppressing autophagy, ER stress, apoptosis and neuroinflammation.
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http://dx.doi.org/10.3389/fncel.2018.00095DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5996884PMC
April 2018

IL-33 Provides Neuroprotection through Suppressing Apoptotic, Autophagic and NF-κB-Mediated Inflammatory Pathways in a Rat Model of Recurrent Neonatal Seizure.

Front Mol Neurosci 2017 19;10:423. Epub 2017 Dec 19.

Department of Forensic Medicine, Medical School of Soochow University, Suzhou, China.

Interleukin-33 (IL-33) is a novel identified chromatin-associated cytokine of IL-1 family cytokines. It signals through a heterodimer comprised of ST2L and IL-1RAcp, and plays a crucial role in many diseases. However, very little is known about the role and underlying intricate mechanisms of IL-33 in recurrent neonatal seizure (RNS). To determine whether IL-33 plays an important regulatory role, we established a neonatal seizure model in this study. Rats were subjected to recurrent seizures induced by inhaling volatile flurothyl. Recombinant IL-33 or PBS were also administered by intraperitoneally (IP) before surgery, respectively. Here, our current results indicated that RNS contributed to a significant reduction in IL-33 and its specific receptor (ST2L) expressions in cortex. While, in hippocampus, RNS induced an increase in IL-33 and ST2L evidently, compared with Sham group. After injection with IL-33, however, a remarkable increase in total IL-33 was detected both in brain cortex and hippocampus. In addition, IL-33 was mainly co-localized in the nuclear of GFAP astrocytes and the cytoplasm of the Iba-1 microglia and IL-33/NeuN merged cells. In parallel, ST2L was expressed mainly in the membrane of GFAP astrocytes, Iba-1 microglia and NeuN neurons, respectively. Furthermore, administration of IL-33 improved RNS-induced behavioral deficits, promoted bodyweight gain, and ameliorated spatial learning and memory ability. Moreover, IL-33 pretreatment blocked the activation of NF-κB, resisted inflammatory cytokines IL-1β and TNF-α increase, as well as suppressed apoptosis and autophagy activation after RNS. Collectively, IL-33 provides potential neuroprotection through suppressing apoptosis, autophagy and at least in part by NF-κB-mediated inflammatory pathways after RNS.
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http://dx.doi.org/10.3389/fnmol.2017.00423DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5742123PMC
December 2017

Wheat germ agglutinin-induced paraptosis-like cell death and protective autophagy is mediated by autophagy-linked FYVE inhibition.

Oncotarget 2017 Oct 24;8(53):91209-91222. Epub 2017 Aug 24.

Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.

Wheat germ agglutinin (WGA) is a lectin that specifically binds cell surface glycoproteins and disrupts nuclear pore complex function through its interaction with POM121. Our data indicate WGA induces paraptosis-like cell death without caspase activation. We observed the main features of paraptosis, including cytoplasmic vacuolation, endoplasmic reticulum dilation and increased ER stress, and the unfolded protein response in WGA-treated cervical carcinoma cells. Conversion of microtubule-associated protein I light chain 3 (LC3-I) into LC3-II and punctuate formation suggestive of autophagy were observed in WGA-treated cells. WGA-induced autophagy antagonized paraptosis in HeLa and CaSKi cells, which expressed autophagy-linked FYVE (Alfy) protein, but not in SiHa cells that did not express Alfy. Alfy knockdown in HeLa cells induced paraptosis-like cell death. These data indicate that WGA-induced cell death occurs through paraptosis and that autophagy may exert a protective effect. WGA treatment and Alfy inhibition could be an effective therapeutic strategy for apoptosis-resistant cervical cancer cells.
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http://dx.doi.org/10.18632/oncotarget.20436DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5710917PMC
October 2017

Tumor-Associated Macrophages Promote Epigenetic Silencing of Gelsolin through DNA Methyltransferase 1 in Gastric Cancer Cells.

Cancer Immunol Res 2017 10 23;5(10):885-897. Epub 2017 Aug 23.

Department of Surgery, National Cheng Kung University Hospital, Tainan, Taiwan.

Epigenetic repression of the tumor suppressor gelsolin (GSN) is frequently observed in cancers. Chronic inflammation can promote tumor progression via aberrant DNA methylation. In this study, we investigated the role of tumor-associated macrophages (TAMs) in DNA methylation of the gene during gastric cancer progression. Immunofluorescence staining of 121 gastric cancer tissues showed aberrant localization of GSN and DNA methyltransferase 1 (DNMT1) and juxtaposition of DNMT1 and M2 TAMs. Decreased GSN protein and mRNA expression and increased DNA methylation in the promoter were observed in gastric cancer cell lines and clinical specimens. To examine the effect of TAMs on DNA methylation in gastric cancer cells, we performed coculture assays and found increased DNMT1 expression but decreased GSN expression in gastric cancer cells after coculture with U937 cells. Knockdown of DNMT1 expression in gastric cancer cells could abort U937 coculture-mediated GSN downregulation. Meanwhile, CCL5 was the main chemokine upregulated in coculture medium. Treatment with CCL5 could induce DNMT1 expression in gastric cancer cells via STAT3 signaling. Inhibiting DNMT1 activity with procainamide, inhibiting DNA methylation with 5-AZA, or inhibiting CCL5/CCR5 signaling with maraviroc reduced tumor growth In conclusion, upregulation of DNMT1 by CCL5/CCR5/STAT3 signaling is critical for TAM-mediated silencing in gastric cancer. This study identified potential targets for gastric cancer therapy. .
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http://dx.doi.org/10.1158/2326-6066.CIR-16-0295DOI Listing
October 2017

KIT Exon 11 Codons 557-558 Deletion Mutation Promotes Liver Metastasis Through the CXCL12/CXCR4 Axis in Gastrointestinal Stromal Tumors.

Clin Cancer Res 2016 07 2;22(14):3477-87. Epub 2016 Mar 2.

Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan. Department of Surgery, National Cheng Kung University Hospital, Tainan, Taiwan.

Purpose: KIT mutations, the most prevalent genetic event in gastrointestinal stromal tumors (GIST), are associated with malignant features and poor prognosis. Aggressive GISTs possess a high propensity to spread to the liver. This study aimed to explore the role of KIT mutations in GIST liver metastasis.

Experimental Design: A total of 170 GISTs were used to determine the association between KIT mutations and liver metastasis. Immunohistochemistry was performed to assess the correlation of KIT mutations with CXCR4 and ETV1 expression. Genetic and pharmacologic methods were used to study the regulation of CXCR4 and ETV1 by KIT mutations.

Results: Codons 557 and 558 in KIT exon 11 were deletion hot spots in GISTs. KIT exon 11 deletions involving codons 557-558 were highly associated with liver metastasis. Overexpression of mutant KIT with exon 11 codons 557-558 deletion (KIT Δ557-558) increased GIST cell motility and liver metastasis. Mechanistically, overexpression of KIT Δ557-558 in GIST cells increased ETV1 and CXCR4 expression. CXCR4 knockdown counteracted KIT Δ557-558-mediated cell migration. Moreover, KIT Δ557-558-induced CXCR4 expression could be abolished by silencing ETV1. The chromatin immunoprecipitation assay showed that ETV1 directly bound to the CXCR4 promoter. After ERK inhibitor PD325901 treatment, the upregulation of ETV1 by KIT Δ557-558 was prevented. In addition, KIT exon 11 codons 557-558 deletion enhanced CXCL12-mediated GIST cell migration and invasion.

Conclusions: KIT exon 11 557-558 deletion upregulates CXCR4 through increased binding of ETV1 to the CXCR4 promoter in GIST cells, which thus promotes liver metastasis. These findings highlighted the potential therapeutic targets for metastatic GISTs. Clin Cancer Res; 22(14); 3477-87. ©2016 AACR.
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http://dx.doi.org/10.1158/1078-0432.CCR-15-2748DOI Listing
July 2016

Blockade of autophagy reduces pancreatic cancer stem cell activity and potentiates the tumoricidal effect of gemcitabine.

Mol Cancer 2015 Oct 12;14:179. Epub 2015 Oct 12.

Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.

Background: Cancer stem cells (CSCs) are considered responsible for the recurrence and chemoresistance of cancer. Dysregulated autophagy is highly prevalent in many types of cancer including pancreatic cancer and has been implicated in cytoprotection and tumor promotion. This study aimed to investigate the role of autophagy in regulating cancer stemness and chemoresistance of pancreatic cancer.

Methods: The correlation between autophagy and CSCs and its clinical significance were analyzed using pancreatic cancer tissue microarrays. Genetic and pharmacological approaches were applied to explore the function of autophagy on CSC activity and gemcitabine resistance of pancreatic cancer cells in vitro and in vivo.

Results: LC3 expression positively correlated with the expression of CSC markers aldehyde dehydrogenase 1 (ALDH1), CD44, and CD133 in pancreatic cancer tissues. High coexpression of LC3/ALDH1 was associated with both poor overall survival and progression-free survival. In pancreatic cancer cell lines, higher LC3-II expression was observed in the sphere-forming cells than in the bulk cells. Blockade of autophagy by silencing ATG5, ATG7, and BECN1 or the administration of autophagy inhibitor chloroquine markedly reduced the CSC populations, ALDH1 activity, sphere formation, and resistance to gemcitabine in vitro and in vivo. Furthermore, osteopontin (OPN) was found to stimulate LC3-II, ALDH1, CD44, and CD133 expression in PANC-1 cells, whereas this effect could be prevented by OPN knockdown and autophagy blockade. After treatment with various inhibitors against the major signaling pathways downstream of OPN, only the inhibitor of NF-κB activation, BAY 1170-82, could effectively counteract OPN-induced autophagy and CSC activity. According to the histochemical results, pancreatic cancer patients manifesting high levels of OPN/LC3/ALDH1 and OPN/CD44/CD133 had poor survival.

Conclusions: Induction of autophagy mediated by OPN/NF-κB signaling is required for maintenance of pancreatic CSC activity. Combination of gemcitabine with pharmacological autophagy inhibitors is a promising therapeutic strategy for pancreatic cancer.
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http://dx.doi.org/10.1186/s12943-015-0449-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4603764PMC
October 2015

Suppressing turbulence of self-propelling rods by strongly coupled passive particles.

Phys Rev E Stat Nonlin Soft Matter Phys 2015 Mar 30;91(3):030302. Epub 2015 Mar 30.

Department of Physics and Center for Complex Systems, National Central University, Jhongli, Taiwan 32001, Republic of China.

The strong turbulence suppression, mainly for large-scale modes, of two-dimensional self-propelling rods, by increasing the long-range coupling strength Γ of low-concentration passive particles, is numerically demonstrated. It is found that large-scale collective rod motion in forms of swirls or jets is mainly contributed from well-aligned dense patches, which can push small poorly aligned rod patches and uncoupled passive particles. The more efficient momentum transfer and dissipation through increasing passive particle coupling leads to the formation of a more ordered and slowed down network of passive particles, which competes with coherent dense active rod clusters. The frustration of active rod alignment ordering and coherent motion by the passive particle network, which interrupt the inverse cascading of forming large-scale swirls, is the key for suppressing collective rod motion with scales beyond the interpassive distance, even in the liquid phase of passive particles. The loosely packed active rods are weakly affected by increasing passive particle coupling due to the weak rod-particle interaction. They mainly contribute to the small-scale modes and high-speed motion.
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http://dx.doi.org/10.1103/PhysRevE.91.030302DOI Listing
March 2015

Pathological characteristics of liver allografts from donation after brain death followed by cardiac death in pigs.

J Huazhong Univ Sci Technolog Med Sci 2014 Oct 16;34(5):687-691. Epub 2014 Oct 16.

Organ Transplant Center, Sun Yat-sen University, Guangzhou, 510080, China.

Donation after brain death followed by circulatory death (DBCD) is a unique practice in China. The aim of this study was to define the pathologic characteristics of DBCD liver allografts in a porcine model. Fifteen male pigs (25-30 kg) were allocated randomly into donation after brain death (DBD), donation after circulatory death (DCD) and DBCD groups. Brain death was induced by augmenting intracranial pressure. Circulatory death was induced by withdrawal of life support in DBCD group and by venous injection of 40 mL 10% potassium chloride in DCD group. The donor livers were perfused in situ and kept in cold storage for 4 h. Liver tissue and common bile duct samples were collected for hematoxylin and eosin staining, TUNEL testing and electron microscopic examination. Spot necrosis was found in hepatic parenchyma of DBD and DBCD groups, while a large area of necrosis was shown in DCD group. The apoptosis rate of hepatocytes in DBD [(0.56±0.30)%] and DBCD [(0.50 ± 0.11)%] groups was much lower than that in DCD group [(3.78±0.33)%] (P<0.05). And there was no significant difference between DBD group and DBCD group (P>0.05)). The structures of bile duct were intact in both DBD and DBCD groups, while the biliary epithelium was totally damaged in DCD group. Under electron microscope, the DBD hepatocytes were characterized by intact cell membrane, well-organized endoplasmic reticulum, mild mitochondria edema and abundant glycogens. Broken cell membrane, mild inflammatory cell infiltration and sinusoidal epithelium edema, as well as reduced glycogen volume, were found in the DBCD hepatocytes. The DCD hepatocytes had more profound cell organelle injury and much less glycogen storage. In conclusion, the preservation injury of DBCD liver allografts is much less severe than that of un-controlled DCD, but more severe than that of DBD liver allografts under electron microscope, which might reflect post-transplant liver function to some extent.
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http://dx.doi.org/10.1007/s11596-014-1337-6DOI Listing
October 2014

Coexpression of CD44-positive/CD133-positive cancer stem cells and CD204-positive tumor-associated macrophages is a predictor of survival in pancreatic ductal adenocarcinoma.

Cancer 2014 Sep 19;120(17):2766-77. Epub 2014 May 19.

Institute of Basic Medical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.

Background: The interactions between cancer stem cells (CSCs) and tumor-associated macrophages (TAMs) can promote tumor progression, maintain the CSCs population, and reduce therapeutic effects. The objective of this study was to investigate the coexpression of CSCs and TAMs and its clinical significance in pancreatic ductal adenocarcinoma (PDAC).

Methods: Ninety-six patients with PDAC were included in this study. Tissue microarrays were constructed for immunostaining of the CSCs markers CD44 and CD133 and the TAMs marker CD204. Correlations between the expression of CSCs and TAMs markers and clinicopathologic characteristics or disease progression were analyzed.

Results: Expression levels of CD44/CD133 and CD204 were significantly higher in tumor tissues than in normal tissues (P < .0001). The variables associated with survival were high coexpression of CD44/CD133 (P = .000), high expression of CD204 (P = .011), and tumor grade (P = .014). There was a positive correlation between CD44/CD133 and CD204 expression (r = 0.294; P = .004). Survival analysis indicated that high coexpression of CD44/CD133 and CD204 was associated significantly with shorter overall survival (P = .000) and disease-free survival (P = .003). Multivariate analysis revealed that high CD44/CD133 expression was an independent prognostic factor for disease-free survival, whereas high CD204 expression was an independent predictor for both overall and disease-free survival.

Conclusions: Coexpression of CD44/CD133 and CD204 is a useful survival prediction marker for patients with PDAC.
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http://dx.doi.org/10.1002/cncr.28774DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4232049PMC
September 2014

Nucleocytoplasmic transport blockage by SV40 peptide-modified gold nanoparticles induces cellular autophagy.

Int J Nanomedicine 2012 8;7:5215-34. Epub 2012 Oct 8.

Institute of Basic Medical Sciences, National Cheng Kung University, and Department of Internal Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.

Gold nanoparticles modified with the nuclear localization signal from simian virus 40 large T antigen (GNP-PEG/SV40) accumulate on the cytoplasmic side of the nuclear membrane in HeLa cells. Accumulation of GNP-PEG/SV40 around the nucleus blocks nucleocytoplasmic transport and prevents RNA export and nuclear shuttling of signaling proteins. This long-term blockage of nucleocytoplasmic transport results in cell death. This cell death is not caused by apoptosis or necrosis because caspases 3 and 9 are not activated, and the expression of annexin V/propidium iodide is not enhanced in HeLa cells after treatment. Using transmission electron microscopy, autophagosomes and autolysosomes were seen to appear after 72 hours of treatment with GNP-PEG/SV40. Increasing levels of enhanced green fluorescent protein-microtubule-associated protein 1 light chain 3 (EGFP-LC3)-positive punctate and LC3-II confirmed GNP-PEG/SV40-induced autophagy. In SiHa cells, treatment did not induce accumulation of GNP-PEG/SV40 around the nucleus and autophagy. Treating cells with wheat germ agglutinin, a nuclear pore complex inhibitor, induced autophagy in both HeLa and SiHa cells. GNP-PEG/SV40-induced autophagy plays a role in cell death, not survival, and virus-mediated small hairpin RNA silencing of Beclin-1 attenuates cell death. Taken together, the results indicate that long-term blockade of nucleocytoplasmic transport results in autophagic cell death.
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http://dx.doi.org/10.2147/IJN.S35125DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3469097PMC
April 2013

Mitochondrial uncoupling protein 2 regulates the effects of paclitaxel on Stat3 activation and cellular survival in lung cancer cells.

Carcinogenesis 2012 Nov 30;33(11):2065-75. Epub 2012 Jul 30.

Graduate Institute of Clinical Medicine, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, No. 35, Xiao-dong Rd, Tainan 704, Taiwan.

Growing evidence suggests that Stat3 contributes to chemoresistance. However, the impact of chemotherapy on Stat3 activity is unclear. We found that paclitaxel activated Stat3 in the human lung cancer cell lines PC14PE6AS2 (AS2) and H157, whereas it reduced Stat3 activation in A549 and H460 cells. Pretreatment of AS2 and H157 cells with rotenone, an inhibitor of mitochondrially produced reactive oxygen species (ROS), or carbonyl cyanide p-(trifluoromethoxy)-phenylhydrazone (FCCP), a mitochondrial uncoupler, suppressed the paclitaxel-induced activation of Stat3. Uncoupling protein 2 (UCP-2), located in the inner membrane of the mitochondria, can reduce ROS production in conditions of oxidative stress. UCP-2 protein expression in the four cancer cell lines was higher than that in normal lung epithelial cells (NL-20), but its expression was lower in AS2 and H157 cells relative to A549 and H460 cells. Silencing high UCP-2 expression with small interfering RNA (siRNA) in A549 and H460 cells restored paclitaxel-induced Stat3 activation. In addition, paclitaxel-induced Stat3 activation led to the upregulation of survivin and Mcl-1, which in turn facilitated cell survival. Moreover, the CL1-5 subline had lower UCP-2 expression relative to the parental CL1-0 cells. Treatment with paclitaxel activated Stat3 in CL1-5 but not in CL1-0 cells, whereas in CL1-5 cells, the overexpression of UCP-2 with complementary DNA (cDNA) blocked Stat3 activation. In lung cancer patients, low UCP-2 expression in cancer cells was a predictor of a poor response to chemotherapy. Therefore, UCP-2 modulates the ROS/Stat3 signaling pathway and response to chemotherapy treatment in lung cancer cells. Targeting UCP-2, ROS and Stat3 pathways may improve anticancer therapies.
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http://dx.doi.org/10.1093/carcin/bgs253DOI Listing
November 2012

[Low and ultralow anterior resection with hand-assisted laparoscopic surgery for rectal cancer].

Zhonghua Wei Chang Wai Ke Za Zhi 2012 Jun;15(6):633-6

Department of Gastrointestinal and Pancreas Surgery, Sun Yat-sen University, Guangzhou, China.

Objective: To summarize the experience and short-term clinical outcomes of hand-assisted laparoscopic surgery (HALS) in sphincter-preserving surgery for low and ultralow rectal cancer.

Methods: Data of 49 patients with rectal cancer who underwent HALS for low or ultralow anterior resection between January 2010 and January 2011 were analyzed retrospectively.

Results: The proximal resection margin was (14.3±6.9) cm and the distal margin was(4.3±1.9) cm. The mean operative time was(128.3±70.9) min. On postoperative macroscopic evaluation, the mesorectum was intact in 42 cases, nearly intact in 7 cases. The circumferential resection margin was more than 2 mm in 42 cases, and less than 2 mm in 7 cases. Forty-six patients underwent R0 resection, and 3 cases underwent R1 resection. The median retrieved lymph node (LN) was 16.20±9.23, and the median positive LN was 1.12±2.19. Postoperative pathological examination showed TNM stage was I( in 12 patients, II(A in 18, II(B in 1, III(A in 2, III(B in 8, III(C in 5, IIII( in 3. The median postoperative hospital stay was (6.25±3.87) d. There were no anastomotic leakage, ileus, intra-abdominal or anastomotic bleeding. There were two wound infections.

Conclusion: Low and ultralow anterior resection for rectal cancer using HALS approach is safe and feasible with favorable short-term outcome.
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June 2012

Activation of the signal transducer and activator of transcription 3 pathway up-regulates estrogen receptor-beta expression in lung adenocarcinoma cells.

Mol Endocrinol 2011 Jul 5;25(7):1145-58. Epub 2011 May 5.

Institute of Basic Medical Sciences, National Cheng Kung University, Medical College, Tainan, Taiwan, Republic of China.

Estrogens contribute to the pathogenesis of female lung cancer and function mainly through estrogen receptor-β (ERβ). However, the way in which ERβ expression is regulated in lung cancer cells remains to be explored. We have found that signal transducer and activator of transcription 3 (Stat3) activation up-regulates ERβ expression in PC14PE6/AS2 lung cancer cells in a preliminary Affymetrix oligonucleotide array study, and we sought to confirm the findings. In this study, we show that IL-6 induced ERβ mRNA and protein expression in lung cancer cells. The induction of ERβ in response to IL-6 was abolished by Janus kinase 2 inhibitor-AG490, dominant-negative mutant of Stat3, and Stat3-targeting short interfering RNA. The luciferase reporter assay and chromatin immunoprecipitation assay confirmed that IL-6-activated Stat3 binds to the ERβ promoter. Besides the Janus kinase 2/Stat3 pathway, the MEK/Erk pathway contributes to ERβ up-regulation induced by IL-6; however, the phosphoinositide 3'-kinase/Akt pathway does not. We also found that epidermal growth factor (EGF) stimulation or L858R mutation in EGF receptor (EGFR) induced Stat3 activation as well as ERβ expression in lung cancer cells. Inhibiting Stat3 activity by pharmacological or genetic approaches reduced EGF- and L858R mutant EGFR-induced ERβ expression, indicating that Stat3 activation is required for EGFR signaling-mediated ERβ up-regulation. Silencing ERβ decreased cell proliferation in lung cancer cells that overexpress L858R mutant EGFR. In conclusion, we have identified that Stat3 activation is essential for ERβ induction by IL-6, EGF, and the presence of EGFR mutation. The findings shed light on new therapeutic targets for female lung cancer, especially for those with EGFR mutations.
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http://dx.doi.org/10.1210/me.2010-0495DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5417244PMC
July 2011

Sphingosine 1-phosphate receptor agonism impairs skin dendritic cell migration and homing to secondary lymphoid tissue: association with prolonged allograft survival.

Transpl Immunol 2008 Nov 9;20(1-2):88-94. Epub 2008 Aug 9.

Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.

The novel immunomodulator FTY720 is a prototypic sphingosine-1-phosphate (S1P) receptor agonist that regulates lymphocyte migration and prolongs allograft survival. Skin dendritic cells (DC) play important roles in cutaneous immunity. We investigated the migration and function of skin DC exposed to FTY720 in vivo, or to its metabolite FTY720 phosphate (P) in vitro. C57BL/10 (H2(b)) recipient (but not donor) FTY720 treatment prolonged median skin C3H (H2(k)) allograft survival significantly, from 12 to 34.5 days. Non-transplanted, FTY720-treated mice revealed a marked increase in skin DC, although total DC in skin-draining lymph nodes (DLN) were unchanged compared with controls. Fewer allogeneic donor DC migrated to DLN of FTY720-treated graft recipients. DC that migrated from the skin of FTY720-treated mice showed reduced MHC class II, CD86 and CCR7 expression, suggesting impaired migratory potential to secondary lymphoid tissue, that correlated with DC retention in skin, and reduced T cell stimulatory activity. Fewer DC migrated from normal skin explants exposed to the FTY720 metabolite, FTY720P than to control medium. DC that did migrate expressed lower levels of MHC class II, CD86 and CCR7, and inferior T cell stimulatory ability. These data demonstrate S1P signaling regulates skin DC trafficking and modulates MHC class II, costimulatory, and homing receptor molecule expression that impairs their ability to elicit allogeneic T cell responses.
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http://dx.doi.org/10.1016/j.trim.2008.07.004DOI Listing
November 2008
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