1
|
Wong CY, Martinez J, Zhao J, Al-Salami H, Dass CR. Development of orally administered insulin-loaded polymeric-oligonucleotide nanoparticles: statistical optimization and physicochemical characterization. Drug Dev Ind Pharm 2020; 46:1238-1252. [PMID: 32597264 DOI: 10.1080/03639045.2020.1788061] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
INTRODUCTION Therapeutic peptides are administered via parenteral route due to poor absorption in the gastrointestinal (GI) tract, instability in gastric acid, and GI enzymes. Polymeric drug delivery systems have achieved significant interest in pharmaceutical research due to its feasibility in protecting proteins, tissue targeting, and controlled drug release pattern. MATERIALS AND METHODS In this study, the size, polydispersity index, and zeta potential of insulin-loaded nanoparticles were characterized by dynamic light scattering and laser Doppler micro-electrophoresis. The main and interaction effects of chitosan concentration and Dz13Scr concentration on the physicochemical properties of the prepared insulin-loaded nanoparticles (size, polydispersity index, and zeta potential) were evaluated statistically using analysis of variance. A robust procedure of reversed-phase high-performance liquid chromatography was developed to quantify insulin release in simulated GI buffer. Results and discussion: We reported on the effect of two independent parameters, including polymer concentration and oligonucleotide concentration, on the physical characteristics of particles. Chitosan concentration was significant in predicting the size of insulin-loaded CS-Dz13Scr particles. In terms of zeta potential, both chitosan concentration and squared term of chitosan were significant factors that affect the surface charge of particles, which was attributed to the availability of positively-charged amino groups during interaction with negatively-charged Dz13Scr. The excipients used in this study could fabricate nanoparticles with negligible toxicity in GI cells and skeletal muscle cells. The developed formulation could conserve the physicochemical properties after being stored for 1 month at 4 °C. CONCLUSION The obtained results revealed satisfactory results for insulin-loaded CS-Dz13Scr nanoparticles (159.3 nm, pdi 0.331, -1.08 mV). No such similar study has been reported to date to identify the main and interactive significance of the above parameters for the characterization of insulin-loaded polymeric-oligonucleotide nanoparticles. This research is of importance for the understanding and development of protein-loaded nanoparticles for oral delivery.
Collapse
Affiliation(s)
- Chun Y Wong
- School of Pharmacy and Biomedical Sciences, Curtin University, Bentley, Australia.,Curtin Health Innovation Research Institute, Bentley, Australia
| | - Jorge Martinez
- School of Pharmacy and Biomedical Sciences, Curtin University, Bentley, Australia
| | - Jian Zhao
- MRC Integrative Epidemiology Unit, University of Bristol, Bristol, UK.,NIHR Bristol Biomedical Research Centre, University of Bristol, Bristol, UK.,Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Hani Al-Salami
- Biotechnology and Drug Development Research Laboratory, School of Pharmacy and Biomedical Sciences, Curtin Health Innovation Research Institute, Bentley, Australia
| | - Crispin R Dass
- School of Pharmacy and Biomedical Sciences, Curtin University, Bentley, Australia.,Curtin Health Innovation Research Institute, Bentley, Australia
| |
Collapse
|
2
|
Lima IAD, Khalil NM, Tominaga TT, Lechanteur A, Sarmento B, Mainardes RM. Mucoadhesive chitosan-coated PLGA nanoparticles for oral delivery of ferulic acid. ARTIFICIAL CELLS NANOMEDICINE AND BIOTECHNOLOGY 2018; 46:993-1002. [DOI: 10.1080/21691401.2018.1477788] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Isabela Angeli de Lima
- Department of Pharmacy, Laboratory of Pharmaceutical Nanotechnology, Universidade Estadual do Centro-Oeste/UNICENTRO, Guarapuava, Brazil
| | - Najeh Maissar Khalil
- Department of Pharmacy, Laboratory of Pharmaceutical Nanotechnology, Universidade Estadual do Centro-Oeste/UNICENTRO, Guarapuava, Brazil
| | - Tania Toyomi Tominaga
- Department of Physics, Universidade Estadual do Centro-Oeste/UNICENTRO, Guarapuava, PR, Brazil
| | - Anna Lechanteur
- INEB – Instituto de Engenharia Biomédica, Universidade do Porto, Porto, Portugal
- Laboratory of Pharmaceutical Technology and Biopharmacy (LPTB) CIRM, Department of Pharmacy, University of Liege, Liege, Belgium
| | - Bruno Sarmento
- INEB – Instituto de Engenharia Biomédica, Universidade do Porto, Porto, Portugal
- i3S – Instituto de Investigação and Inovação em Saúde, Universidade do Porto, Porto, Portugal
- CESPU – Instituto de Investigação e Formação Avançada em Ciências and Tecnologias da Saúde, Gandra, Portugal
| | - Rubiana Mara Mainardes
- Department of Pharmacy, Laboratory of Pharmaceutical Nanotechnology, Universidade Estadual do Centro-Oeste/UNICENTRO, Guarapuava, Brazil
| |
Collapse
|
3
|
Alizadeh Naini M, Kavousipour S, Hasanzarini M, Nasrollah A, Monabati A, Mokarram P. O6-Methyguanine-DNA Methyl Transferase (MGMT) Promoter Methylation in Serum DNA of Iranian Patients with
Colorectal Cancer. Asian Pac J Cancer Prev 2018; 19:1223-1227. [PMID: 29801405 PMCID: PMC6031839 DOI: 10.22034/apjcp.2018.19.5.1223] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Introduction: Colorectal cancer (CRC) is a leading cause of cancer deaths worldwide but current molecular targeted therapy is not providing major success in CRC treatment, so early detection by non-invasive methods continues to be vital. Aberrant methylation of CpG islands in promoter regions is associated with inactivation of various tumor suppressor genes. O6-methyguanine-DNA methyltransferase (MGMT) is a DNA repair enzyme that removes mutagenic and cytotoxic adducts from O6-guanine in DNA. Aberrant hypermethylation of the MGMT promoter has been associated with lack of mRNA expression, with concomitant loss of protein content and enzyme activity. AIM: Our aim was to determine whether MGMT promoter methylation might be detectable in circulating free DNA in the serum of CRC patients and normal individuals using a methylation specific (MSP) polymerase chain reaction (PCR) method. Methods: A total of 70 subjects were enrolled in the study. Of these, 30 patients who were diagnosed previously as untreated colon adenocarcinoma by a gastroenterologist and the other 40 were nearly age-matched individuals who had a normal colonoscopic evaluation (except for hemorrhoids or fissures) and normal pathologic reports. After bisulphite modification of DNA, serum samples were examined for MGMT promoter methylation using MSP. Results: Ninety percent of CRC patients had MGMT promoter hypermethylation as compared to no methylation in normal subjects’ serum. Most of the cancers were stage П and moderately differentiated adenocarcinomas; nearly 60% were found in the left colon. No statistically significant correlation was found between the promoter methylation status and gender and age. Discussion and Conclusions: MGMT hypermethylation can be detected in free circulating DNA in serum of CRC patients and can be used “as a clinical biomarker” for early diagnosis and prognostic assessment of the disease. Our data confirm previous studies indicating utility for free circulating DNA as a serum biomarker for early detection, diagnosis and monitoring of CRC patients.
Collapse
Affiliation(s)
- Mahvash Alizadeh Naini
- Gastroenterohepatology Research Center, Nemazi Hospital, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.,Department of Internal Medicine, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
| | | | | | | | | | | |
Collapse
|
4
|
Shalaby SM, El-Shal AS, Abdelaziz LA, Abd-Elbary E, Khairy MM. Promoter methylation and expression of DNA repair genes MGMT and ERCC1 in tissue and blood of rectal cancer patients. Gene 2018; 644:66-73. [DOI: 10.1016/j.gene.2017.10.056] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Revised: 09/30/2017] [Accepted: 10/18/2017] [Indexed: 01/26/2023]
|
5
|
Methylation of MGMT and ADAMTS14 in normal colon mucosa: biomarkers of a field defect for cancerization preferentially targeting elder African-Americans. Oncotarget 2016; 6:3420-31. [PMID: 25638164 PMCID: PMC4413663 DOI: 10.18632/oncotarget.2852] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Accepted: 12/04/2014] [Indexed: 12/24/2022] Open
Abstract
Somatic hypermethylation of the O6-methylguanine-DNA methyltransferase gene (MGMT) was previously associated with G > A transition mutations in KRAS and TP53 in colorectal cancer (CRC). We tested the association of MGMT methylation with G > A mutations in KRAS and TP53 in 261 CRCs. Sixteen cases, with and without MGMT hypermethylation, were further analyzed by exome sequencing. No significant association of MGMT methylation with G > A mutations in KRAS, TP53 or in the whole exome was found (p > 0.5 in all comparisons). The result was validated by in silico comparison with 302 CRCs from The Cancer Genome Atlas (TCGA) consortium dataset. Transcriptional silencing associated with hypermethylation and stratified into monoallelic and biallelic. We also found a significant clustering (p = 0.001) of aberrant hypermethylation of MGMT and the matrix metalloproteinase gene ADAMTS14 in normal colonic mucosa of CRC patients. This suggested the existence of an epigenetic field defect for cancerization disrupting the methylation patterns of several loci, including MGMT or ADAMTS14, that may lead to predictive biomarkers for CRC. Methylation of these loci in normal mucosa was more frequent in elder (p = 0.001) patients, and particularly in African Americans (p = 1 × 10−5), thus providing a possible mechanistic link between somatic epigenetic alterations and CRC racial disparities in North America.
Collapse
|
6
|
Marzese DM, Hoon DS. Emerging technologies for studying DNA methylation for the molecular diagnosis of cancer. Expert Rev Mol Diagn 2015; 15:647-64. [PMID: 25797072 DOI: 10.1586/14737159.2015.1027194] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
DNA methylation is an epigenetic mechanism that plays a key role in regulating gene expression and other functions. Although this modification is seen in different sequence contexts, the most frequently detected DNA methylation in mammals involves cytosine-guanine dinucleotides. Pathological alterations in DNA methylation patterns are described in a variety of human diseases, including cancer. Unlike genetic changes, DNA methylation is heavily influenced by subtle modifications in the cellular microenvironment. In all cancers, aberrant DNA methylation is involved in the alteration of a large number of oncological pathways with relevant theranostic utility. Several technologies for DNA methylation mapping have been developed recently and successfully applied in cancer studies. The scope of these technologies varies from assessing a single cytosine-guanine locus to genome-wide distribution of DNA methylation. Here, we review the strengths and weaknesses of these approaches in the context of clinical utility for the molecular diagnosis of human cancers.
Collapse
Affiliation(s)
- Diego M Marzese
- Department of Molecular Oncology, Saint John's Health Center, John Wayne Cancer Institute, 2200 Santa Monica Blvd, Santa Monica, CA 90404, USA
| | | |
Collapse
|
7
|
Zheng CG, Jin C, Ye LC, Chen NZ, Chen ZJ. Clinicopathological significance and potential drug target of O6-methylguanine-DNA methyltransferase in colorectal cancer: a meta-analysis. Tumour Biol 2015; 36:5839-48. [PMID: 25716203 DOI: 10.1007/s13277-015-3254-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 02/10/2015] [Indexed: 12/18/2022] Open
Abstract
Emerging evidence indicates that O(6)-methylguanine-DNA methyltransferase (MGMT) is a candidate for tumor suppression in several types of human tumors including colorectal cancer (CRC). However, the correlation between MGMT hypermethylation and clinicopathological characteristics of CRC remains unclear. In this study, we conducted a systematic review and meta-analysis to quantitatively evaluate the effects of MGMT hypermethylation on the incidence of CRC and clinicopathological characteristics. A comprehensive literature search was done from Web of Science, the Cochrane Library Database, PubMed, EMBASE, CINAHL, and the Chinese Biomedical Database for related research publications written in English and Chinese. Methodological quality of the studies was also evaluated. Analyses of pooled data were performed with Review Manager 5.2. Odds ratio (OR) and hazard ratio (HR) were calculated and summarized, respectively. Final analysis from 28 eligible studies was performed. MGMT hypermethylation is found to be significantly higher in CRC than in normal colorectal mucosa, the pooled OR from 13 studies including 1085 CRC and 899 normal colorectal mucosa, OR = 6.04, 95 % confidence interval (CI) = 4.69-7.77, p < 0.00001. MGMT hypermethylation is also significantly higher in colorectal adenoma than in normal colorectal mucosa, but it is significantly less compared to that in CRC patients. Interestingly, MGMT hypermethylation is correlated with sex status and is significantly higher in female than in male. MGMT hypermethylation is also associated with high levels of microsatellite instability (MSI). The pooled HR for overall survival (OS) shows that MGMT hypermethylation is not associated with worse survival in CRC patients. The results of this meta-analysis suggest that MGMT hypermethylation is associated with an increased risk and high levels of MSI and may play an important role in CRC initiation. However, MGMT hypermethylation may play an important role in the early stage of CRC progression and development, as well as having limited value in prediction of prognosis in CRC patients. We also discussed that MGMT may serve as a potential drug target of CRC.
Collapse
Affiliation(s)
- Chen-Guo Zheng
- Department of Coloproctology, The Second Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, People's Republic of China
| | | | | | | | | |
Collapse
|
8
|
Schlinkert P, Casals E, Boyles M, Tischler U, Hornig E, Tran N, Zhao J, Himly M, Riediker M, Oostingh GJ, Puntes V, Duschl A. The oxidative potential of differently charged silver and gold nanoparticles on three human lung epithelial cell types. J Nanobiotechnology 2015; 13:1. [PMID: 25592092 PMCID: PMC4304186 DOI: 10.1186/s12951-014-0062-4] [Citation(s) in RCA: 115] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 12/18/2014] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Nanoparticle (NPs) functionalization has been shown to affect their cellular toxicity. To study this, differently functionalized silver (Ag) and gold (Au) NPs were synthesised, characterised and tested using lung epithelial cell systems. METHODS Monodispersed Ag and Au NPs with a size range of 7 to 10 nm were coated with either sodium citrate or chitosan resulting in surface charges from -50 mV to +70 mV. NP-induced cytotoxicity and oxidative stress were determined using A549 cells, BEAS-2B cells and primary lung epithelial cells (NHBE cells). TEER measurements and immunofluorescence staining of tight junctions were performed to test the growth characteristics of the cells. Cytotoxicity was measured by means of the CellTiter-Blue ® and the lactate dehydrogenase assay and cellular and cell-free reactive oxygen species (ROS) production was measured using the DCFH-DA assay. RESULTS Different growth characteristics were shown in the three cell types used. A549 cells grew into a confluent mono-layer, BEAS-2B cells grew into a multilayer and NHBE cells did not form a confluent layer. A549 cells were least susceptible towards NPs, irrespective of the NP functionalization. Cytotoxicity in BEAS-2B cells increased when exposed to high positive charged (+65-75 mV) Au NPs. The greatest cytotoxicity was observed in NHBE cells, where both Ag and Au NPs with a charge above +40 mV induced cytotoxicity. ROS production was most prominent in A549 cells where Au NPs (+65-75 mV) induced the highest amount of ROS. In addition, cell-free ROS measurements showed a significant increase in ROS production with an increase in chitosan coating. CONCLUSIONS Chitosan functionalization of NPs, with resultant high surface charges plays an important role in NP-toxicity. Au NPs, which have been shown to be inert and often non-cytotoxic, can become toxic upon coating with certain charged molecules. Notably, these effects are dependent on the core material of the particle, the cell type used for testing and the growth characteristics of these cell culture model systems.
Collapse
Affiliation(s)
- Paul Schlinkert
- Department of Molecular Biology, Paris Lodron-University of Salzburg, Hellbrunnerstr. 34, A-5020, Salzburg, Austria.
| | - Eudald Casals
- Institute Catalá de Nanotecnologia, Barcelona, Spain.
| | - Matthew Boyles
- Department of Molecular Biology, Paris Lodron-University of Salzburg, Hellbrunnerstr. 34, A-5020, Salzburg, Austria.
| | - Ulrike Tischler
- Department of Molecular Biology, Paris Lodron-University of Salzburg, Hellbrunnerstr. 34, A-5020, Salzburg, Austria.
| | - Eva Hornig
- Department of Molecular Biology, Paris Lodron-University of Salzburg, Hellbrunnerstr. 34, A-5020, Salzburg, Austria.
| | - Ngoc Tran
- Institute Catalá de Nanotecnologia, Barcelona, Spain.
| | - Jiayuan Zhao
- Institute for Work and Health, Lausanne, Switzerland.
| | - Martin Himly
- Department of Molecular Biology, Paris Lodron-University of Salzburg, Hellbrunnerstr. 34, A-5020, Salzburg, Austria.
| | - Michael Riediker
- Institute for Work and Health, Lausanne, Switzerland.
- Institue for Occupational Medicine (IOM) Singapore, Downtown Core, Singapore.
| | - Gertie Janneke Oostingh
- Department of Molecular Biology, Paris Lodron-University of Salzburg, Hellbrunnerstr. 34, A-5020, Salzburg, Austria.
- Biomedical Sciences, Salzburg University of Applied Sciences, Puch, Salzburg, Austria.
| | - Victor Puntes
- Institute Catalá de Nanotecnologia, Barcelona, Spain.
| | - Albert Duschl
- Department of Molecular Biology, Paris Lodron-University of Salzburg, Hellbrunnerstr. 34, A-5020, Salzburg, Austria.
| |
Collapse
|
9
|
Oliver JA, Ortiz R, Melguizo C, Álvarez PJ, Gómez-Millán J, Prados J. Prognostic impact of MGMT promoter methylation and MGMT and CD133 expression in colorectal adenocarcinoma. BMC Cancer 2014; 14:511. [PMID: 25015560 PMCID: PMC4227111 DOI: 10.1186/1471-2407-14-511] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Accepted: 07/07/2014] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND New biomarkers are needed for the prognosis of advanced colorectal cancer, which remains incurable by conventional treatments. O6-methylguanine DNA methyltransferase (MGMT) methylation and protein expression have been related to colorectal cancer treatment failure and tumor progression. Moreover, the presence in these tumors of cancer stem cells, which are characterized by CD133 expression, has been associated with chemoresistance, radioresistance, metastasis, and local recurrence. The objective of this study was to determine the prognostic value of CD133 and MGMT and their possible interaction in colorectal cancer patients. METHODS MGMT and CD133 expression was analyzed by immunohistochemistry in 123 paraffin-embedded colorectal adenocarcinoma samples, obtaining the percentage staining and intensity. MGMT promoter methylation status was obtained by using bisulfite modification and methylation-specific PCR (MSP). These values were correlated with clinical data, including overall survival (OS), disease-free survival (DFS), tumor stage, and differentiation grade. RESULTS Low MGMT expression intensity was significantly correlated with shorter OS and was a prognostic factor independently of treatment and histopathological variables. High percentage of CD133 expression was significantly correlated with shorter DFS but was not an independent factor. Patients with low-intensity MGMT expression and ≥50% CD133 expression had the poorest DFS and OS outcomes. CONCLUSIONS Our results support the hypothesis that MGMT expression may be an OS biomarker as useful as tumor stage or differentiation grade and that CD133 expression may be a predictive biomarker of DFS. Thus, MGMT and CD133 may both be useful for determining the prognosis of colorectal cancer patients and to identify those requiring more aggressive adjuvant therapies. Future studies will be necessary to determine its clinical utility.
Collapse
Affiliation(s)
- Jaime Antonio Oliver
- Institute of Biopathology and Regenerative Medicine (IBIMER), University of Granada, Granada 18100, Spain
| | - Raúl Ortiz
- Institute of Biopathology and Regenerative Medicine (IBIMER), University of Granada, Granada 18100, Spain
- Department of Health Sciences, University of Jaén, Jaén 23071, Spain
- Biosanitary Institute of Granada (ibs.GRANADA), SAS-Universidad de Granada, Granada, Spain
| | - Consolación Melguizo
- Institute of Biopathology and Regenerative Medicine (IBIMER), University of Granada, Granada 18100, Spain
- Biosanitary Institute of Granada (ibs.GRANADA), SAS-Universidad de Granada, Granada, Spain
- Department of Anatomy and Embryology, University of Granada, Granada 18012, Spain
| | - Pablo Juan Álvarez
- Institute of Biopathology and Regenerative Medicine (IBIMER), University of Granada, Granada 18100, Spain
- Biosanitary Institute of Granada (ibs.GRANADA), SAS-Universidad de Granada, Granada, Spain
| | - Jaime Gómez-Millán
- Radiation Oncology Department, Hospital Clinico Universitario Virgen de la Victoria, Málaga 29010, Spain
| | - Jose Prados
- Institute of Biopathology and Regenerative Medicine (IBIMER), University of Granada, Granada 18100, Spain
- Biosanitary Institute of Granada (ibs.GRANADA), SAS-Universidad de Granada, Granada, Spain
- Department of Anatomy and Embryology, University of Granada, Granada 18012, Spain
| |
Collapse
|
10
|
Biocompatible multi-walled carbon nanotube-chitosan-folic acid nanoparticle hybrids as GFP gene delivery materials. Colloids Surf B Biointerfaces 2013; 111:224-31. [PMID: 23831590 DOI: 10.1016/j.colsurfb.2013.06.010] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 06/03/2013] [Accepted: 06/05/2013] [Indexed: 12/31/2022]
Abstract
Carbon nanotube (CNT) is one of the inorganic delivery systems that show great potential for optimal biomolecule transporting. Concerning the preparation of CNT-based delivery vectors, it is very important to understand the internal relations of physical properties and surface functionalization of CNTs with the transfection efficiency and cytotoxicity. In this paper, the multi-walled CNTs (MWCNTs) of different length were functionalized with chitosan-folic acid nanoparticles (CS-FA NPs) by ionotropic gelation process. The micromorphologies, surface functional groups, and zeta potential of the MWCNT-CS-FA NPs were characterized. The effects of nanotube length and surface functionalization with CS-FA NPs on the gene transfection efficiency and cytotoxicity were investigated in detail. The non-functionalized MWCNTs and MWCNT-CS-FA NPs all can deliver the plasmid DNA of enhanced green fluorescent protein (pEGFP-N1) into HeLa and MCF-7 cells and the exogenous GFP gene has been expressed. The nanotube length shows a compromise influence on the transfection and cytotoxicity properties of MWCNTs. Having greater gene transfection ability, however, the shorter MWCNTs exhibit larger cytotoxicity than the longer ones. Moreover, the surface functionalization of MWCNTs with CS-FA NPs improves the transfection efficiency and decreases the cytotoxicity as well. Under optimal conditions, the pEGFP-N1 transfection efficiency of MWCNT-CS-FA NPs is about 4.1%, being 1.5 times as large as that of the non-functionalized MWCNTs. The MWCNT-CS-FA NPs show little effect on the cellular viability when the concentration is up to 250 μg mL(-1). By optimal length control and surface functionalization, MWCNTs should have good applications in gene delivery vectors.
Collapse
|
11
|
Amatu A, Sartore-Bianchi A, Moutinho C, Belotti A, Bencardino K, Chirico G, Cassingena A, Rusconi F, Esposito A, Nichelatti M, Esteller M, Siena S. Promoter CpG island hypermethylation of the DNA repair enzyme MGMT predicts clinical response to dacarbazine in a phase II study for metastatic colorectal cancer. Clin Cancer Res 2013; 19:2265-72. [PMID: 23422094 DOI: 10.1158/1078-0432.ccr-12-3518] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE O(6)-methylguanine-DNA-methyltransferase (MGMT) is a DNA repair protein removing mutagenic and cytotoxic adducts from O(6)-guanine in DNA. Approximately 40% of colorectal cancers (CRC) display MGMT deficiency due to the promoter hypermethylation leading to silencing of the gene. Alkylating agents, such as dacarbazine, exert their antitumor activity by DNA methylation at the O(6)-guanine site, inducing base pair mismatch; therefore, activity of dacarbazine could be enhanced in CRCs lacking MGMT. We conducted a phase II study with dacarbazine in CRCs who had failed standard therapies (oxaliplatin, irinotecan, fluoropyrimidines, and cetuximab or panitumumab if KRAS wild-type). EXPERIMENTAL DESIGN All patients had tumor tissue assessed for MGMT as promoter hypermethylation in double-blind for treatment outcome. Patients received dacarbazine 250 mg/m(2) intravenously every day for four consecutive days, every 21 days, until progressive disease or intolerable toxicity. We used a Simon two-stage design to determine whether the overall response rate would be 10% or more. Secondary endpoints included association of response, progression-free survival, and disease control rate with MGMT status. RESULTS Sixty-eight patients were enrolled from May 2011 to March 2012. Patients received a median of three cycles of dacarbazine (range 1-12). Grades 3 and 4 toxicities included: fatigue (41%), nausea/vomiting (29%), constipation (25%), platelet count decrease (19%), and anemia (18%). Overall, two patients (3%) achieved partial response and eight patients (12%) had stable disease. Disease control rate (partial response + stable disease) was significantly associated with MGMT promoter hypermethylation in the corresponding tumors. CONCLUSION Objective clinical responses to dacarbazine in patients with metastatic CRC are confined to those tumors harboring epigenetic inactivation of the DNA repair enzyme MGMT.
Collapse
Affiliation(s)
- Alessio Amatu
- Department of Hematology and Oncology, Ospedale Niguarda Ca' Granda, Milan, Italy
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Chen Z, Xiao L, Liu W, Liu D, Xiao YY, Chen J, Liu X, Li WD, Li W, Cai BC. Novel materials which possess the ability to target liver cells. Expert Opin Drug Deliv 2012; 9:649-56. [PMID: 22480167 DOI: 10.1517/17425247.2012.679261] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Hepatic-targeted drug delivery systems are designed to treat diseases of the liver. However, since there are several different types of liver diseases that are caused by different cells, it is important to select the proper materials to target these different cells. AREAS COVERED This review addresses novel materials that possess the ability to target liver cells via receptor-ligand processes and offers an insight into the aspects of formulation design. It also discusses several approaches used to enhance the targeting efficiency of drug delivery systems to receptors in the liver cells. In addition, the delivery efficiency and therapeutic efficacy of these materials in the treatment of acute or chronic liver diseases is highlighted. EXPERT OPINION Further research into the use of clinical materials and the design of smart materials for multi-drug delivery to different organelles is important for future studies on these new materials. It is hoped that these targeted therapeutics will benefit patients with liver disorders in the near future.
Collapse
Affiliation(s)
- Zhipeng Chen
- Nanjing University of Chinese Medicine, Department of Pharmacy, Nanjing 210046, PR China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Brell M, Ibáñez J, Tortosa A. O6-Methylguanine-DNA methyltransferase protein expression by immunohistochemistry in brain and non-brain systemic tumours: systematic review and meta-analysis of correlation with methylation-specific polymerase chain reaction. BMC Cancer 2011; 11:35. [PMID: 21269507 PMCID: PMC3039628 DOI: 10.1186/1471-2407-11-35] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2010] [Accepted: 01/26/2011] [Indexed: 11/15/2022] Open
Abstract
Background The DNA repair protein O6-Methylguanine-DNA methyltransferase (MGMT) confers resistance to alkylating agents. Several methods have been applied to its analysis, with methylation-specific polymerase chain reaction (MSP) the most commonly used for promoter methylation study, while immunohistochemistry (IHC) has become the most frequently used for the detection of MGMT protein expression. Agreement on the best and most reliable technique for evaluating MGMT status remains unsettled. The aim of this study was to perform a systematic review and meta-analysis of the correlation between IHC and MSP. Methods A computer-aided search of MEDLINE (1950-October 2009), EBSCO (1966-October 2009) and EMBASE (1974-October 2009) was performed for relevant publications. Studies meeting inclusion criteria were those comparing MGMT protein expression by IHC with MGMT promoter methylation by MSP in the same cohort of patients. Methodological quality was assessed by using the QUADAS and STARD instruments. Previously published guidelines were followed for meta-analysis performance. Results Of 254 studies identified as eligible for full-text review, 52 (20.5%) met the inclusion criteria. The review showed that results of MGMT protein expression by IHC are not in close agreement with those obtained with MSP. Moreover, type of tumour (primary brain tumour vs others) was an independent covariate of accuracy estimates in the meta-regression analysis beyond the cut-off value. Conclusions Protein expression assessed by IHC alone fails to reflect the promoter methylation status of MGMT. Thus, in attempts at clinical diagnosis the two methods seem to select different groups of patients and should not be used interchangeably.
Collapse
Affiliation(s)
- Marta Brell
- Department of Neurosurgery, Son Dureta University Hospital, Palma de Mallorca, Spain.
| | | | | |
Collapse
|
14
|
Deschoolmeester V, Baay M, Specenier P, Lardon F, Vermorken JB. A review of the most promising biomarkers in colorectal cancer: one step closer to targeted therapy. Oncologist 2010; 15:699-731. [PMID: 20584808 PMCID: PMC3228001 DOI: 10.1634/theoncologist.2010-0025] [Citation(s) in RCA: 114] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Accepted: 05/01/2010] [Indexed: 02/06/2023] Open
Abstract
Rapidly growing insights into the molecular biology of colorectal cancer (CRC) and recent developments in gene sequencing and molecular diagnostics have led to high expectations for the identification of molecular markers to be used in optimized and tailored treatment regimens. However, many of the published data on molecular biomarkers are contradictory in their findings and the current reality is that no molecular marker, other than the KRAS gene in the case of epidermal growth factor receptor (EGFR)- targeted therapy for metastatic disease, has made it into clinical practice. Many markers investigated suffer from technical shortcomings, resulting from lack of quantitative techniques to capture the impact of the molecular alteration. This understanding has recently led to the more comprehensive approaches of global gene expression profiling or genome-wide analysis to determine prognostic and predictive signatures in tumors. In this review, an update of the most recent data on promising biological prognostic and/or predictive markers, including microsatellite instability, epidermal growth factor receptor, KRAS, BRAF, CpG island methylator phenotype, cytotoxic T lymphocytes, forkhead box P3-positive T cells, receptor for hyaluronic acid-mediated motility, phosphatase and tensin homolog, and T-cell originated protein kinase, in patients with CRC is provided.
Collapse
Affiliation(s)
- Vanessa Deschoolmeester
- Laboratory of Cancer Research and Clinical Oncology, Department of Medical Oncology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium.
| | | | | | | | | |
Collapse
|
15
|
Sharma G, Mirza S, Parshad R, Srivastava A, Gupta SD, Pandya P, Ralhan R. Clinical significance of promoter hypermethylation of DNA repair genes in tumor and serum DNA in invasive ductal breast carcinoma patients. Life Sci 2010; 87:83-91. [PMID: 20470789 DOI: 10.1016/j.lfs.2010.05.001] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2009] [Revised: 04/23/2010] [Accepted: 04/29/2010] [Indexed: 10/19/2022]
Abstract
AIMS The clinical relevance of frequent methylation of CpG islands of key cancer genes in breast cancer is being increasingly recognized. Our study aimed to evaluate the promoter methylation status of DNA repair genes-BRCA1MGMT and GSTP1 in tumor and circulating DNA of invasive ductal breast carcinoma patients. MAIN METHODS Methylation-specific PCR was carried out to investigate the promoter methylation status of genes in tumor and circulating DNA of 100 breast cancer patients in a prospective study. The effect of promoter methylation on protein expression was evaluated by immunohistochemistry. KEY FINDINGS The frequency of tumor hypermethylation was 27% in BRCA1, 32% in MGMT and 25% in GSTP1 and correlated with methylation of these genes in paired serum DNA. Immunohistochemical analysis showed no detectable expression of BRCA1 and MGMT in 51/89 (57%) and 35/89 (39%) tumors, respectively. MGMT promoter methylation mediated gene silencing was associated with loss of its protein expression (p=0.002, O.R.=4.5, 95% C.I.=1.7-12.0). BRCA1 promoter methylation was not associated with loss of its protein expression, indicating that methylation is not the sole mechanism accounting for the loss/reduced BRCA1 protein expression. Importantly, GSTP1 and BRCA1 hypermethylation were found to be independent of other prognostic factors in predicting disease recurrence (p=0.02, HR=7.6, 95% C.I.=1.4-44.1; p=0.04, HR=6.2, 95% C.I.=1.1-35.7). SIGNIFICANCE Our study underscores the potential utility of DNA methylation of these genes in serum as a promising biomarker and can serve as a surrogate for tumor DNA methylation for diagnosis and prognosis of breast cancer.
Collapse
Affiliation(s)
- Gayatri Sharma
- Department of Biochemistry, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India
| | | | | | | | | | | | | |
Collapse
|
16
|
Mirza S, Sharma G, Pandya P, Ralhan R. Demethylating agent 5-aza-2-deoxycytidine enhances susceptibility of breast cancer cells to anticancer agents. Mol Cell Biochem 2010; 342:101-9. [DOI: 10.1007/s11010-010-0473-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2009] [Accepted: 04/17/2010] [Indexed: 12/21/2022]
|
17
|
YUREGIR OOZALP, YURTCU E, KIZILKILIC E, KOCER NE, OZDOGU H, SAHIN FI. Detecting methylation patterns ofp16,MGMT,DAPKandE-cadheringenes in multiple myeloma patients. Int J Lab Hematol 2010; 32:142-9. [DOI: 10.1111/j.1751-553x.2009.01146.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
18
|
Chen SP, Chiu SC, Wu CC, Lin SZ, Kang JC, Chen YL, Lin PC, Pang CY, Harn HJ. The association of methylation in the promoter of APC and MGMT and the prognosis of Taiwanese CRC patients. Genet Test Mol Biomarkers 2009; 13:67-71. [PMID: 19309276 DOI: 10.1089/gtmb.2008.0045] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
AIMS The purpose of this study was to investigate the association of methylation in the promoter regions of adenomatous polyposis coli (APC) and O(6)-methylguanine-DNA methyltransferase (MGMT) and the survival of Taiwanese colorectal cancer (CRC) subjects who received 5-fluorouracil (5-FU) adjuvant chemotherapy. RESULTS DNA isolated from tumor tissue of 117 CRC subjects was analyzed for the existence of methylation in the promoter regions of APC and MGMT by methylation-specific PCR. Various characteristics of the 117 subjects were recorded and used in the Cox proportional-hazard model analyses. Methylation in the promoter region is 62.4% (73/117) for APC and 60.7% (71/117) for MGMT in our CRC patients. Subjects presenting methylation in the APC promoter demonstrate significantly lower hazards for all causes of death (hazard ratios=0.378, p=0.011) or CRC deaths (hazard ratios=0.426, p=0.039). However, no significant correlation is found between the methylation of MGMT promoter and the prognosis of CRC subjects. In addition, no interaction between 5-FU adjuvant chemotherapy and methylation of the two genes are observed. CONCLUSIONS Methylation in the APC promoter may serve as a predictor for the prognosis of Taiwanese CRC patients.
Collapse
Affiliation(s)
- Shee-Ping Chen
- Institute of Medical Sciences, Tzu-Chi University, Hualien, Taiwan, Republic of China
| | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Huang CC, Chien WP, Wong RH, Cheng YW, Chen MC, Lee H. NAT2 fast acetylator genotype and MGMT promoter methylation may contribute to gender difference in K-RAS mutation occurrence in Taiwanese colorectal cancer. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2009; 50:127-133. [PMID: 19107910 DOI: 10.1002/em.20444] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A recent study conducted by our group showed that the NAT2 fast acetylator genotype is associated with an increasing risk for the development of colorectal cancer (CRC), especially for females. We therefore examined whether a higher risk of CRC in females with the NAT2 fast acetylator genotype was associated with the occurrence of K-RAS mutation, and to further verify whether MGMT promoter methylation was linked to the occurrence of K-RAS mutation in patients with the NAT2 fast acetylator genotype. Herein, 151 CRC cases were examined for NAT2 genetic polymorphisms and MGMT promoter methylation by PCR-RFLP and methylation-specific PCR (MSP). The results of this study show that the NAT2 fast acetylator genotype is associated with the occurrence of K-RAS mutation in female cases (OR = 4.820, 95% CI = 1.113-20.873), but not associated with MGMT promoter methylation. Surprisingly, MGMT promoter methylation significantly deepens the impact of NAT2 fast acetylation on K-RAS mutation in the female cases (OR = 5.129, 95% CI = 1.092-24.105). In conclusion, Taiwanese women with the NAT2 fast acetylator genotype may exhibit a higher risk of CRC with increased occurrence of K-RAS mutation. Detection of NAT2 genotypes and MGMT promoter methylation may be useful in the risk assessment for CRC in Taiwanese women.
Collapse
Affiliation(s)
- Chi-Chou Huang
- Colorectal Division, Department of Surgery, Chung Shan Medical University Hospital, Taichung, Taiwan, Republic of China
| | | | | | | | | | | |
Collapse
|
20
|
Abstract
Cancer is an ever-increasing menace that needs to be curbed soon. Though chemotherapy is successful to some extent, the main drawbacks of chemotherapy is the limited accessibility of drugs to the tumor tissues requiring high doses, their intolerable toxicity, development of multiple drug resistance and their non-specific targeting. Nanoparticles (NPs), an evolution of nanotechnology, have the potential to successfully address these problems related to drug delivery and retention and are considered potential candidates to carry drugs to the desired site of therapeutic action. In this review, we give an overview of the use of clinically applicable NPs mainly for cancer therapy. We also focus on the different types of nanoscale polymer carriers used for the delivery of chemotherapeutic agents and the mechanisms that facilitate their targeted delivery to tumor cells.
Collapse
Affiliation(s)
- Suphiya Parveen
- Laboratory of Nanomedicine, Institute of Life Sciences, Bhubaneswar, India
| | | |
Collapse
|
21
|
Bishehsari F, Mahdavinia M, Malekzadeh R, Verginelli F, Catalano T, Sotoudeh M, Bazan V, Agnese V, Esposito DL, De Lellis L, Semeraro D, Colucci G, Hormazdi M, Rakhshani N, Cama A, Piantelli M, Iacobelli S, Russo A, Mariani-Costantini R. Patterns of K-ras mutation in colorectal carcinomas from Iran and Italy (a Gruppo Oncologico dell'Italia Meridionale study): influence of microsatellite instability status and country of origin. Ann Oncol 2008; 17 Suppl 7:vii91-6. [PMID: 16760302 DOI: 10.1093/annonc/mdl959] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND K-ras mutations are a key step in colorectal cancer progression. Such mutations have been widely studied in case series from Western countries but there are few data on the rate and spectrum of mutations in tumors from countries where the epidemiological features of the disease are different. PATIENTS AND METHODS Tumor samples from 182 Iranian colorectal cancer patients (170 sporadic cases and 12 HNPCC cases) were screened for K-ras mutations at codons 12, 13 and 61 by sequencing analysis. The cases were also characterized for microsatellite instability at mononucleotide repeats by PCR and fragment analysis, and classified according to microsatellite instability status. The frequency and the spectrum of K-ras mutations were compared with those observed in a series of colorectal cancer patients from Italy. RESULTS K-ras mutations were observed in 68/182 (37.4%) cases. Mutation frequencies were similar in HNPCC-associated, sporadic MSI-H and sporadic microsatellite-stable (MSS) tumors. However, the G13D substitution was more frequent in HNPCC (3/4, 75%) and sporadic MSI-H (7/11, 63.6%) tumors compared to sporadic MSS tumors (11/53, 20.4%) (P <0.01). Comparison of mutations in the two series from Iran and Italy showed a significantly higher frequency of G13D among Italian patients. CONCLUSIONS While the frequency of K-ras mutations could be similar, the mutational spectrum could be differentially influenced by genetic and environmental factors.
Collapse
Affiliation(s)
- F Bishehsari
- Department of Oncology and Neurosciences, University G. d'Annunzio, and Center of Excellence on Aging (CeSI), G. d'Annunzio University Foundation, Chieti, Italy
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Martien R, Loretz B, Thaler M, Majzoob S, Bernkop-Schnürch A. Chitosan–thioglycolic acid conjugate: An alternative carrier for oral nonviral gene delivery? J Biomed Mater Res A 2007; 82:1-9. [PMID: 17265441 DOI: 10.1002/jbm.a.31135] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Regarding safety concerns, nonviral gene delivery vehicles that have the required efficiency and safety for use in human gene therapy are being widely investigated. The aim of this study was to synthesize and evaluate a thiolated chitosan to improve the efficacy of oral gene delivery systems. Thiolated chitosan was synthesized by introducing thioglycolic acid (TGA) to chitosan via amide bond formation mediated by a carbodiimide. Based on this conjugate, nanoparticles with pDNA were generated at pH 4.0 and 5.0. Cytotoxicity of the thiolated chitosan/pDNA nanoparticles on Caco-2 cells was evaluated. The diameter of thiolated chitosan/pDNA nanoparticles was in the range of 100-200 nm. The zeta potential was determined to be 5-6 mV. Due to stability toward nucleases, the transfection rate of thiolated chitosan/pDNA nanoparticles was fivefold higher than that of unmodified chitosan/pDNA nanoparticles. Lactate dehydrogenase tests for thiolated chitosan/pDNA (pH 4.0 and 5.0) showed that (3.79 +/- 0.23)% and (2.9 +/- 0.13)% cell damage. According to these results, thiolated chitosan represents promising excipients for preparation DNA nanoparticles in nonviral gene delivery system.
Collapse
Affiliation(s)
- Ronny Martien
- Department of Pharmaceutical Technology, Institute of Pharmacy, Leopold-Franzens-University of Innsbruck, Innrain 52, 6020 Innsbruck, Austria
| | | | | | | | | |
Collapse
|
23
|
Qi J, Zhu YQ, Luo J, Tao WH. Hypermethylation and expression regulation of secreted frizzled-related protein genes in colorectal tumor. World J Gastroenterol 2006; 12:7113-7. [PMID: 17131472 PMCID: PMC4087771 DOI: 10.3748/wjg.v12.i44.7113] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the functions of promoter hyper-methylation of secreted frizzled-related proteins (sFRPs) genes in colorectal tumorigenesis and progression.
METHODS: The promoter hypermethylation and expression of sFRP genes in 72 sporadic colorectal carcinomas, 33 adenomas, 18 aberrant crypt foci (ACF) and colorectal cancer cell lines RKO, HCT116 and SW480 were detected by methylation-specific PCR and reverse transcription PCR, respectively.
RESULTS: None of the normal colorectal mucosa tissues showed methylated bands of any of four sFRP genes. sFRP1, 2, 4 and 5 were frequently methylated in colorectal carcinoma, adenoma and ACF (sFRP1 > 85%, sFRP2 >75%, sFRP5 > 50%), and the differences between three colorectal tissues were not significant (P > 0.05). Methylation in colorectal tumors was more frequent than in normal mucosa and adjacent normal mucosa. The mRNA of sFRP1-5 genes was expressed in all normal colorectal mucosa samples. Expression of sFRP1, 2, 4 and 5 and sFRP1, 2 and 5 was downregulated in carcinoma and adenoma, respectively. The downregulation of sFRP2, 4 and 5 was more frequent in carcinoma than in adenoma. Expression of sFRP3 which promoter has no CpG island was downregulated in only a few of colorectal tumor samples (7/105). The downregulation of sFRP1, 2, 4 and 5 expression was significantly associated with promoter hypermethylation in colorectal tumor. After cells were treated by DAC/TSA combination, the silenced sFRP mRNA expression could be effectively re-expressed in colorectal cancer cell lines.
CONCLUSION: Hypermethylation of sFRP genes is a common early event in the evolution of colorectal tumor, occurring frequently in ACF, which is regarded as the earliest lesion of multistage colorectal carcinogenesis. It appears to functionally silence sFRP genes expression. Methylation of sFRP1, 2 and 5 genes might serve as indicators for colorectal tumor.
Collapse
Affiliation(s)
- Jian Qi
- Department of Gastroenterology, Zhongnan Hospital of Wuhan University, Wuhan, 430071, Hubei Province, China
| | | | | | | |
Collapse
|
24
|
Qi L, Xu Z. In vivo antitumor activity of chitosan nanoparticles. Bioorg Med Chem Lett 2006; 16:4243-5. [PMID: 16759859 DOI: 10.1016/j.bmcl.2006.05.078] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2006] [Revised: 05/20/2006] [Accepted: 05/22/2006] [Indexed: 11/26/2022]
Abstract
Chitosan nanoparticles have been synthesized as potential anticancer agents, and evaluated, in vitro, against various cancer cell lines. In this study, in vivo antitumor activity of chitosan nanoparticles against Sarcoma-180 and mouse hepatoma H22 was investigated. Chitosan nanoparticles showed significant antitumor activity in vivo. The doses and particle size made a great effect on their efficacy.
Collapse
Affiliation(s)
- Lifeng Qi
- Zhejiang University, Nano-Biology Lab of Animal Science College, Hangzhou, PR China.
| | | |
Collapse
|
25
|
Dueñas-González A, Lizano M, Candelaria M, Cetina L, Arce C, Cervera E. Epigenetics of cervical cancer. An overview and therapeutic perspectives. Mol Cancer 2005; 4:38. [PMID: 16248899 PMCID: PMC1291396 DOI: 10.1186/1476-4598-4-38] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2005] [Accepted: 10/25/2005] [Indexed: 12/22/2022] Open
Abstract
Cervical cancer remains one of the greatest killers of women worldwide. It is difficult to foresee a dramatic increase in cure rate even with the most optimal combination of cytotoxic drugs, surgery, and radiation; therefore, testing of molecular targeted therapies against this malignancy is highly desirable. A number of epigenetic alterations occur during all stages of cervical carcinogenesis in both human papillomavirus and host cellular genomes, which include global DNA hypomethylation, hypermetylation of key tumor suppressor genes, and histone modifications. The reversible nature of epigenetic changes constitutes a target for transcriptional therapies, namely DNA methylation and histone deacetylase inhibitors. To date, studies in patients with cervical cancer have demonstrated the feasibility of reactivating the expression of hypermethylated and silenced tumor suppressor genes as well as the hyperacetylating and inhibitory effect upon histone deacetylase activity in tumor tissues after treatment with demethylating and histone deacetylase inhibitors. In addition, detection of epigenetic changes in cytological smears, serum DNA, and peripheral blood are of potential interest for development of novel biomolecular markers for early detection, prediction of response, and prognosis.
Collapse
Affiliation(s)
- Alfonso Dueñas-González
- Unidad de Investigación Biomédica en Cáncer, Instituto Nacional de Cancerología/Instituto de Investigaciones Biomédicas (INCan/IIB), Universidad Nacional Autónoma de Mexico (UNAM), Mexico City. Mexico
| | - Marcela Lizano
- Unidad de Investigación Biomédica en Cáncer, Instituto Nacional de Cancerología/Instituto de Investigaciones Biomédicas (INCan/IIB), Universidad Nacional Autónoma de Mexico (UNAM), Mexico City. Mexico
| | - Myrna Candelaria
- Division of Clinical Research, Instituto Nacional de Cancerología (INCan), Mexico City, Mexico
| | - Lucely Cetina
- Division of Clinical Research, Instituto Nacional de Cancerología (INCan), Mexico City, Mexico
| | - Claudia Arce
- Division of Clinical Research, Instituto Nacional de Cancerología (INCan), Mexico City, Mexico
| | - Eduardo Cervera
- Division of Clinical Research, Instituto Nacional de Cancerología (INCan), Mexico City, Mexico
| |
Collapse
|