Publications by authors named "Zhiwei Xiao"

18 Publications

  • Page 1 of 1

Advances in Cyclic Nucleotide Phosphodiesterase-Targeted PET Imaging and Drug Discovery.

J Med Chem 2021 06 27;64(11):7083-7109. Epub 2021 May 27.

Department of Radiology, Division of Nuclear Medicine and Molecular Imaging Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, Massachusetts 02114, United States.

Cyclic nucleotide phosphodiesterases (PDEs) control the intracellular concentrations of cAMP and cGMP in virtually all mammalian cells. Accordingly, the PDE family regulates a myriad of physiological functions, including cell proliferation, differentiation and apoptosis, gene expression, central nervous system function, and muscle contraction. Along this line, dysfunction of PDEs has been implicated in neurodegenerative disorders, coronary artery diseases, chronic obstructive pulmonary disease, and cancer development. To date, 11 PDE families have been identified; however, their distinct roles in the various pathologies are largely unexplored and subject to contemporary research efforts. Indeed, there is growing interest for the development of isoform-selective PDE inhibitors as potential therapeutic agents. Similarly, the evolving knowledge on the various PDE isoforms has channeled the identification of new PET probes, allowing isoform-selective imaging. This review highlights recent advances in PDE-targeted PET tracer development, thereby focusing on efforts to assess disease-related PDE pathophysiology and to support isoform-selective drug discovery.
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http://dx.doi.org/10.1021/acs.jmedchem.1c00115DOI Listing
June 2021

Metastatic Colorectal Cancer Patient With Microsatellite Stability and BRAF Mutation Showed a Complete Metabolic Response to PD-1 Blockade and Bevacizumab: A Case Report.

Front Oncol 2021 27;11:652394. Epub 2021 Apr 27.

Cancer Center, First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China.

A vast majority of colorectal cancer (CRC) patients with microsatellite stability (MSS) or proficient mismatch repair (pMMR) are refractory to immunotherapeutic strategies. The current research focusses on the combined treatment strategies for identification and optimization in order to improve the efficacy of immunotherapy among patients with microsatellite stability (MSS), who account for the majority of metastatic colorectal cancer (mCRC) cases. mCRC patients harboring MSS and the show a worse prognosis and barely benefit from immunotherapy. In this report, we discuss the case of a mCRC patient with MSS and , who exhibited significant response to the combined treatment with nivolumab and bevacizumab, and has been exhibiting a progression-free survival (PFS) of more than 17 months. Our findings indicate that combined anti-angiogenic therapy can improve the efficacy of immunotherapy, which results in the prolong survival of the patient. This is a case report on MSS and colorectal cancer which presents with a response to immunotherapy and anti-angiogenic therapy.
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http://dx.doi.org/10.3389/fonc.2021.652394DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8112237PMC
April 2021

Comprehensive TCM treatments combined with chemotherapy for advanced non-small cell lung cancer: A randomized, controlled trial.

Medicine (Baltimore) 2021 May;100(18):e25690

Oncology Center, The First Affiliated Hospital of Guangzhou University of Chinese Medicine.

Objective: We conducted this study to evaluate the efficacy and safety of traditional Chinese medicine (TCM) in advanced non-small cell lung cancer (NSCLC) patients who underwent chemotherapy.

Design: This was a prospective, open-label, randomized controlled trial. NSCLC patients at stage IIIA, IIIB, or IV were randomly assigned to either TCM plus chemotherapy or chemotherapy alone. The comprehensive TCM treatment consisted of Kang Ai injection, herbal decoction, and Zhenqifuzheng capsules. The primary endpoint was quality of life (QOL) measured by the Functional Assessment of Cancer Therapy-Lung version 4.0. The secondary endpoints were chemotherapy completion rate, tumor response, and adverse events. All assessments were done at baseline, the third week, and the sixth week.

Results: Thirty-nine participants were randomly assigned to the treatment group and 36 to the control group. The QOL scores were significantly improved in the treatment group compared with those of the control group in social well-being (cycle 1, P = .048; cycle 2, P = .015), emotional well-being (cycle 1, P = .047; cycle 2, P = 4.29E-05), and functional well-being (cycle 1, P = .030; cycle 2, P = .003), while the QOL scores in the above 3 domains declined in the control group (P < .05). Both groups had a decline in the physical well-being score (cycle 1, P = .042; cycle 2, P = .017) and lung cancer symptom score (cycle 1, P = .001; cycle 2, P = .001) after 2 courses of intervention. The deterioration in physical well-being and lung cancer symptoms was noticeably smaller in the treatment group (P < .05). There were significant differences between the 2 groups in social well-being, emotional well-being, functional well-being, lung cancer symptom domain, and the total score (P < .05). Patients in the treatment group had a significantly lower incidence of platelet reduction than the control group (P = .028) after 2 cycles of treatment. No significant difference in nonhematological adverse events (AEs) was observed.

Conclusion: This study illustrated that comprehensive TCM treatment could promote the QOL of NSCLC patients, alleviate symptoms, and reduce the AEs caused by chemotherapy, verifying the synergistic and attenuating effects of TCM in NSCLC patients undergoing chemotherapy.

Trial Registration: Chinese Clinical Trial Registry (www.chictr.org.cn): ChiCTR-TRC-13003637.
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http://dx.doi.org/10.1097/MD.0000000000025690DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8104195PMC
May 2021

Downregulation of lncRNA TSLNC8 promotes melanoma resistance to BRAF inhibitor PLX4720 through binding with PP1α to re-activate MAPK signaling.

J Cancer Res Clin Oncol 2021 Mar 3;147(3):767-777. Epub 2021 Jan 3.

Dermatology and STD Department, Affiliated Hospital of Nantong University, Jiangsu, China.

Purpose: Approximately 60% of patients with melanoma harbor BRAF mutation and targeting BRAF offers enormous advance in the treatment of those patients. Unfortunately, the efficacy of the BRAF inhibitors is usually restricted by the onset of drug resistance. Therefore, better understanding of the adaptive drug resistance mechanisms is essential for the development of alternative therapeutic strategies, and offers more promising measures to promote the short duration of response to BRAF inhibitors.

Methods: The levels of tumor suppressive long noncoding RNA on chromosome 8p12 (TSLNC8) were evaluated by qPCR. The MTT assay, colony formation assay, apoptosis assay, and in vivo xenograft tumor model were performed to assess the functions of TSLNC8 on drug resistance. Western blotting, RNA pull-down, and RNA immunoprecipitation (RIP) assays were applied to investigate the mechanisms of TSLNC8 in melanoma.

Results: Herein, our findings demonstrate that TSLNC8 is significantly downregulated in BRAF inhibitor-resistant melanoma tissues and cells. Moreover, downregulation of TSLNC8 in BRAF inhibitor sensitive cells reduces the toxicity response to BRAF inhibitor PLX4720, and inhibits apoptosis of melanoma cells-treated with PLX4720. Further assay elucidates that TSLNC8 can bind with the catalytic subunit of protein phosphatase 1α (PP1α) to regulate its distribution, and Downregulation of TSLNC8 results in PP1α cytoplasmic accumulation, thus re-activating the MAPK signaling. Eventually, the overexpression of TSLNC8 in BRAF inhibitor PLX4720-resistant melanoma cells restores the sensitive to BRAF inhibitor.

Conclusion: Collectively, our research provides a compelling rationale for resistance to BRAF inhibitor in melanoma, and the patient might benefit from the combinatorial therapy of BRAF inhibitors and lncRNA TSLNC8.
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http://dx.doi.org/10.1007/s00432-020-03484-4DOI Listing
March 2021

Primary Resistance to Brigatinib in a Patient with Lung Adenocarcinoma Harboring G1202R Mutation and Rearrangement.

Onco Targets Ther 2020 22;13:4591-4595. Epub 2020 May 22.

Oncology Center, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510405, Guangdong, People's Republic of China.

Purpose: Anaplastic lymphoma kinase () inhibitors have transformed the management of non-small-cell lung cancer (NSCLC) patients with gene rearrangement. This paper reports a new resistance mechanism to a second-generation ALK inhibitor, brigatinib.

Case Report: A 43-year-old woman who had no history of smoking was diagnosed with stage IVa (T2bN2M1b) lung adenocarcinoma. After the first-line chemotherapy failed, the patient received crizotinib due to the presence of fusion by next-generation sequencing (NGS). The patient had disease progression after 8 months on crizotinib, and a second NGS identified the G1202R resistance mutation. Therefore, she was switched to brigatinib. After only 53 days of treatment with brigatinib, the patient developed a new 1.6×1.2 cm lesion in the mediastinal lymph node. A third NGS testing revealed a new form of rearrangement (). The patient died 16 months after diagnosis.

Conclusion: This paper provides new insights into the primary resistance to brigatinib in NSCLC patients carrying G1202R mutation. The new fusion form of NTRK rearrangement was detected, which may provide potential treatment options after brigatinib resistance.
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http://dx.doi.org/10.2147/OTT.S249652DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7250292PMC
May 2020

Visible-light induced decarboxylative coupling of redox-active esters with disulfides to construct C-S bonds.

Chem Commun (Camb) 2020 Apr;56(30):4164-4167

Key Laboratory of Tropical Medicinal Resources of Ministry of Education, Collaborative Innovation Center of Tropical Biological Resources, Hainan Normal University, Hainan, Haikou 571158, China.

A novel method has been established for the construction of C-S bonds using redox-active esters with disulfides in the presence of Ru-photoredox catalyst. This method exhibits remarkable functional group tolerance across a wide scope of substrates. Under mild conditions, a structurally diverse array of aryl alkyl sulfides is successfully and efficiently obtained through decarboxylative cross-coupling.
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http://dx.doi.org/10.1039/d0cc00451kDOI Listing
April 2020

Efficacy and safety of Jianpishengsui for chemotherapy-related fatigue in patients with non-small cell lung cancer: study protocol for a randomized placebo-controlled clinical trial.

Trials 2020 Jan 16;21(1):94. Epub 2020 Jan 16.

Oncology Center, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510405, Guangdong, China.

Background: Chemotherapy-related fatigue (CRF) is a common symptom in non-small cell lung cancer (NSCLC) patients. A Chinese herbal formula cream for oral application, called Jianpishengsui (JPSS), is extensively used in the First Affiliated Hospital of Guangzhou University of Chinese Medicine as an internal preparation for CRF and is associated with a promising response. Due to the lack of high-quality clinical evidence, a randomized placebo-controlled trial is required to assess the efficacy and safety of JPSS.

Methods/design: The efficacy and safety of JPSS herbal formula cream will be evaluated through a prospective, randomized, placebo-controlled trial conducted in the First Affiliated Hospital of Guangzhou University of Chinese Medicine. NSCLC patients with CRF will be randomized into two groups at a ratio of 1:1. Each group will receive either 15 g of the oral JPSS herbal formula cream or placebo twice a day from day 6 to day 20 during two courses of paclitaxel + platinum/docetaxel + platinum/pemetrexed + platinum (TP/DP/AP) chemotherapy. The primary endpoint is the difference in the degree of fatigue between baseline (the day before the start of the intervention) and day 42, which will be assessed by the Revised Piper Fatigue Scale score. The secondary endpoints are quality of life (measured by the 43-item European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Lung Cancer C43), Eastern Cooperative Oncology Group Performance Status, and Traditional Chinese Medicine syndrome score. The toxicity of the treatments will also be evaluated at the same time. All outcomes will be measured at baseline, day 6, day 21, and day 42 of the treatment.

Discussion: This randomized trial will investigate the efficacy and safety of JPSS applied for CRF in patients with NSCLC.

Trial Registration: Chinese Clinical Trial Registry, ChiCTR1900023451. Registered on 28 May 2019.
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http://dx.doi.org/10.1186/s13063-019-3982-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6966901PMC
January 2020

Treatment of consistent BRAF/HRAS gene mutation and MYC amplification radiation-induced abdominal wall angiosarcoma with low-dose apatinib: a case report.

BMC Cancer 2019 Dec 5;19(1):1188. Epub 2019 Dec 5.

Cancer Center, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, 510405, Guangzhou, Guangdong, People's Republic of China.

Background: An extremely rare condition, radiation-induced angiosarcoma is characterized by a poor prognosis, high recurrence rate and lack of effective treatment. Herein, we present a case report of a 48-year-old female patient with radiation-induced abdominal wall angiosarcoma who showed a dramatic response to low-dose apatinib.

Case Presentation: The patient, who was diagnosed with cervical squamous cell carcinoma 20 years ago, had received radiotherapy and chemotherapy after operation. Angiosarcomas of the abdominal wall appeared 9 years later. After repeated surgical operations and intravenous chemotherapy for the angiosarcomas, the patient developed tumor recurrence and pulmonary metastasis. The abdominal wall tumors showed repeated rupture and bleeding, with poor wound healing. On evaluation, laboratory findings detected the negative serum tumor markers CEA, CA 125, CA 15-3 and CA 19-9. Imaging showed multiple subcutaneous nodules and masses in the abdominal wall, accompanied by suspected small subpleural nodule at the lower lobe of the right lung. Immunohistochemistry of previous surgical pathology indicated that CD31, ERG and Vim were positive. The result of whole exome sequencing suggested the mutations of BRAF and HRAS, and the amplification of MYC. Based on the above results, the patient was clinically diagnosed with radiation-induced angiosarcoma of the abdominal wall with pulmonary metastasis. The patient was treated with low-dose apatinib and rejected reoperation or chemotherapy.

Results: At the 6-month follow-up visit, the abdominal wall lesions that had previously ruptured stopped bleeding and showed significant shrinkage. Imaging showed that most of the abdominal wall lesions had partially regressed, and some of the lesions on the abdominal wall and the suspected lesion of subpleural nodule at the lower lobe of the right lung had disappeared.

Conclusions: We described this case and reviewed the literature on radiation-related angiosarcoma. Importantly, this case suggests that apatinib may be an effective and sensitive treatment for radiation-induced angiosarcoma even at the lowest dosage, without aggravating the bleeding of lesions.
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http://dx.doi.org/10.1186/s12885-019-6351-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6896664PMC
December 2019

Sunitinib-and-Chinese herbal medicine-based systematic treatment clinically cured a patient with multiple metastatic primary clear cell carcinoma of the liver: a case report.

Onco Targets Ther 2019 12;12:2823-2828. Epub 2019 Apr 12.

Oncology Department, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangdong, People's Republic of China,

Primary clear cell carcinoma of the liver (PCCCL) is a rare and special type of primary hepatocellular carcinoma. However, treatment methods for multiple metastatic PCCCL are lacking. Here, we report the case of a 55-year-old male PCCCL patient with multiple metastatic lesions who was clinically cured by sunitinib-based systematic treatment. This patient was diagnosed with PCCCL in Liver Segment 7, Child-Pugh A liver function, Stage A in November 16, 2009, and received radical excision of the cancer immediately. His disease recurred with multiple metastatic lesions in the liver and other parts of the body, including the retroperitoneal lymph nodes, lung and bilateral adrenal nodules in June 29, 2012. The biopsy results showed that the lung mass was lung metastasis of PCCCL. With Child-Pugh A liver function, Stage C of PCCCL was diagnosed. Sunitinib (37.5 mg, oral, once a day [qd]) in combination with Chinese herbal medicine (CHM) was given. The tumor size steadily reduced, and the lesions were no longer obvious in May 21, 2014. The patient had multiple metastases and is in complete response (CR) state until now. He is considered as clinically cured. From the initial diagnosis of PCCCL, the survival period reached 8 years.
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http://dx.doi.org/10.2147/OTT.S197923DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6469470PMC
April 2019

MiR-139-5p, miR-940 and miR-193a-5p inhibit the growth of hepatocellular carcinoma by targeting SPOCK1.

J Cell Mol Med 2019 04 1;23(4):2475-2488. Epub 2019 Feb 1.

Cancer Center, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China.

The study was aimed to screen out miRNAs with differential expression in hepatocellular carcinoma (HCC), and to explore the influence of the expressions of these miRNAs and their target gene on HCC cell proliferation, invasion and apoptosis. MiRNAs with differential expression in HCC were screened out by microarray analysis. The common target gene of these miRNAs (miR-139-5p, miR-940 and miR-193a-5p) was screened out by analysing the target genes profile (acquired from Targetscan) of the three miRNAs. Expression levels of miRNAs and SPOCK1 were determined by quantitative real time polymerase chain reaction (qRT-PCR). The target relationships were verified by dual luciferase reporter gene assay and RNA pull-down assay. Through 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide,thiazolyl blue tetrazolium bromide (MTT) and transwell assays and flow cytometry, HCC cell viability, invasion and apoptosis were determined. In vivo experiment was conducted in nude mice to investigate the influence of three miRNAs on tumour growth. Down-regulation of miR-139-5p, miR-940 and miR-193a-5p was found in HCC. Overexpression of these miRNAs suppressed HCC cell viability and invasion, promoted apoptosis and inhibited tumour growth. SPOCK1, the common target gene of miR-139-5p, miR-940 and miR-193a-5p, was overexpressed in HCC. SPOCK1 overexpression promoted proliferation and invasion, and restrained apoptosis of HCC cells. MiR-139-5p, miR-940 and miR-193a-5p inhibited HCC development through targeting SPOCK1.
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http://dx.doi.org/10.1111/jcmm.14121DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6433657PMC
April 2019

Zinc-Mediated Intermolecular Reductive Radical Fluoroalkylsulfination of Unsaturated Carbon-Carbon Bonds with Fluoroalkyl Bromides and Sulfur Dioxide.

Chemistry 2019 Feb 7;25(7):1824-1828. Epub 2019 Jan 7.

Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, P. R. China.

A versatile and general zinc-mediated intermolecular reductive radical fluoroalkylsulfination of unsaturated C-C bonds has been developed using readily available fluoroalkyl bromides and 1,4-diazabicyclo[2.2.2]octane-bis(sulfur dioxide) adduct (DABSO) with wide substrate scope and excellent functional group tolerance. Sulfur dioxide anion radical generated in situ from the reduction of sulfur dioxide with zinc may be involved in the reaction mechanism.
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http://dx.doi.org/10.1002/chem.201805526DOI Listing
February 2019

Development of anti-biofouling feed spacers to improve performance of reverse osmosis modules.

Water Res 2018 11 31;145:599-607. Epub 2018 Aug 31.

School of Sustainable Engineering and the Built Environment, Arizona State University, United States; Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment, Arizona State University, Tempe, AZ, United States. Electronic address:

This study investigates the biofouling resistance of modified reverse osmosis (RO) feed spacers. Control spacers (made of polypropylene) were functionalized with a biocidal coating (silver), hydrophilic (SiO nanoparticles) or superhydrophobic (TMPSi-TiO nanoparticles) anti-adhesive coatings, or a hybrid hydrophilic-biocidal coating (graphene oxide). Performance was measured by adhesion assays, viability tests, and permeate flow decline in a bench scale RO system. The control spacers proved to be one of the better performing materials based on bacterial deposition and dynamic RO fouling experiments. The good anti-adhesive properties of the control can be explained by its near ideal surface free energy (SFE). The only surface modification that significantly reduced biofouling compared to the control was the biocidal silver coating, which outperformed the other spacers by all measured indicators. Therefore, future efforts to improve spacer materials for biofouling control should focus on engineering biocidal coatings, rather than anti-adhesive ones.
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http://dx.doi.org/10.1016/j.watres.2018.08.068DOI Listing
November 2018

Oxidative Radical Intermolecular Trifluoromethylthioarylation of Styrenes by Arenediazonium Salts and Copper(I) Trifluoromethylthiolate.

J Org Chem 2018 05 20;83(10):5836-5843. Epub 2018 Apr 20.

Key Laboratory of Organofluorine Chemistry , Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , China.

An efficient oxidative radical intermolecular trifluoromethylthioarylation of styrenes with arenediazonium salts and copper(I) trifluoromethylthiolate under mild conditions is described for the first time. The reactions provide good yields of the corresponding trifluoromethylthioarylation products with broad substrate scope and excellent functional group compatibility.
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http://dx.doi.org/10.1021/acs.joc.8b00650DOI Listing
May 2018

Reverse correlation of Jab1 and Smad4 in PANC-1 cells involved in the pathogenesis of pancreatic cancer.

Int J Clin Exp Pathol 2015 1;8(8):9279-85. Epub 2015 Aug 1.

Department of Endocrinology, First Affiliated Hospital, Medical School of Shihezi University Shihezi 832002, China.

Objective: Steps in the genetic basis of pancreatic cancer (PC) have been recently identified, however, Studies focusing on the relationship between Jab1 and Smad4 in PC are rarely reported. This study was performed to examine the expression patterns and association of Jab1 and Smad4 in PC cells for gaining a further understanding of PC pathogenesis.

Methods: Human pancreatic cancer cell line PANC-1 cells were infected with retrovirus vector containing GFP, HA-Jab1, siGFP, and siJab1 respectively. The expression of Jab1 and Smad4 in PANC-1 cells was analyzed by Western blot and immunocytochemistry. Subsequently, the effect of overexpression of Jab1 on cell proliferation inhibition mediated by TGF-β was examined with MTT colorimetry.

Results: The expression of Smad4 in PANC-1 cells was inhibited after the overexpression of Jab1. Inversely, the expression of Smad4 was increased after the down-regulation of Jab1 silenced by SiRNA. Smad4 expression in PANC-1 cells was negatively correlated with Jab1 expression. In addition, the cell proliferation inhibitory effect induced by TGF-β in PANC-1 cells was attenuated after the overexpression of Jab1.

Conclusions: The reverse correlation of Jab1 and Smad4 in PANC-1 cells may be involved in the Pathogenesis of PC. Jab1 can cause degradation of Smad4 via TGF-β signal pathway, consequently contributing to the proliferation of PC cells.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4583909PMC
August 2016

Anti-tumor effect and mechanism of cyclooxygenase-2 inhibitor through matrix metalloproteinase 14 pathway in PANC-1 cells.

Int J Clin Exp Pathol 2015 1;8(2):1737-42. Epub 2015 Feb 1.

Department of Endocrinology, First Affiliated Hospital, Medical College of Shihezi University Shihezi 832002, China.

Objective: To investigate whether celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, can attenuate proliferation, migration, invasion and MMP-14 expression in pancreatic cancer cells PANC-1 and the possible anti-tumor mechanism of celecoxib.

Methods: Human pancreatic cancer cell line PANC-1 cells were treated with diverse concentrations of celecoxib (20, 60, 100 μmol/L). Cell proliferation, invasion and migration capabilities were measured by MTT colorimetry, transwell invasion assay, and scratch assay separately. At the same time, the protein expression of COX-2 and MMP-14 was assessed by ELISA.

Results: The capabilities of proliferation, invasion and migration in PANC-1 cells were attenuated in a concentration-dependent manner after treated with celecoxib, followed by the down-regulation of the protein expression of COX-2 and MMP-14. In addition, MMP-14 expression was significantly positively correlated with COX-2 expression.

Conclusions: COX-2 inhibitor celecoxib can inhibit the proliferation, invasion and migration of PANC-1 cells via down-regulating the expression of MMP-14 in a concentration-dependent manner, thus contributing to its anti-tumor effect in pancreatic cancer.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4396316PMC
February 2016

Direct trifluoromethylthiolation of unactivated C(sp(3))-H using silver(I) trifluoromethanethiolate and potassium persulfate.

Angew Chem Int Ed Engl 2015 Mar 23;54(13):4070-4. Epub 2015 Feb 23.

Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, 200032, Shanghai (China).

A practical and efficient method for the direct trifluoromethylthiolation of unactivated C(sp(3) )H bonds by AgSCF3 /K2 S2 O8 under mild conditions is described. The reaction has a good functional-group tolerance and good selectivity. Initial mechanistic investigations indicate that the reaction may involve a radical process in which K2 S2 O8 plays key roles in both the activation of the C(sp(3) )H bond and the oxidation of AgSCF3 .
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http://dx.doi.org/10.1002/anie.201411953DOI Listing
March 2015

Versatile surface micropatterning and functionalization enabled by microcontact printing of poly(4-aminostyrene).

Langmuir 2014 Nov 31;30(44):13483-90. Epub 2014 Oct 31.

Department of Chemical and Biomedical Engineering and ‡Department of Industrial and Manufacturing Engineering, FAMU-FSU College of Engineering, Florida State University , Tallahassee, Florida 32310, United States.

Microcontact printing (μCP) of polyelectrolytes is a facile and powerful method for surface micro/nanopatterning and functionalization. Poly(4-aminostyrene) (PAS) is a polyelectrolyte that can be converted to aryldiazonium salt and exhibits pH-dependent hydrophobicity. Here we demonstrate μCP of PAS and the expansion of this technique in various directions. First, the microcontact-printed PAS can be diazotized to micropattern biomolecules including DNA and protein and nanomaterials including single-walled carbon nanotubes and gold nanoparticles. Second, the diazotized PAS enables μCP of a metallic structure on a carbon surface. Third, the hydrophobic nature of PAS at the neutral pH allows the microcontact-printed PAS-based polyelectrolyte multilayer to be used as masks for wet etching. Lastly, this technique allows facile fabrication of highly engineered microparticles with a unique structure. Overall, this work has established a novel μCP platform with various potential applications.
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http://dx.doi.org/10.1021/la503393jDOI Listing
November 2014

A paper indicator for triple-modality sensing of nitrite based on colorimetric assay, Raman spectroscopy, and electron paramagnetic resonance spectroscopy.

Analyst 2013 Nov;138(24):7303-7

Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Integrative NanoScience Institute, Florida State University, 2525 Pottsdamer Street, Tallahassee, Florida 32310, USA.

Paper indicators based on colorimetric assays are widely used for nitrite detection, but their application to liquids with strong colours is restricted. We report a novel paper indicator that allows for sensing nitrite by colorimetric assay, Raman spectroscopy, and electron paramagnetic resonance spectroscopy with non-overlapping signal wavelength ranges through non-contact means. The paper indicator was prepared by impregnating poly(4-aminostyrene), 2-naphthol and single-walled carbon nanotubes in a regular filter paper. All three ingredients were essential to realize the triple-modality sensing. This method is simple and inexpensive, and promises to have wider applicability than the existing paper indicators.
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http://dx.doi.org/10.1039/c3an01604hDOI Listing
November 2013