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1.
Childs Nerv Syst ; 40(3): 813-821, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37851125

ABSTRACT

PURPOSE: The consistency and accuracy of paediatric TBI triage tools can be affected by different factors, such as patients' characteristics and the level of knowledge and skill of the caregiver. This systematic review included all the available data on the level of agreement between paramedics and ED physicians about the reliability of tools to identify paediatric TBI and the diagnostic accuracy of several such tools in prehospital settings when used by paramedics. METHODS: MEDLINE (OVID), EMBASE (OVID), Cochrane Library (OVID), and CINAHL Plus (EBSCO) databases were searched from inception to 27 October 2022. Quality, bias, and applicability were assessed using COSMIN for interobserver reliability studies and QUADAS-2 tool for diagnostic accuracy studies. Narrative synthesis was employed because data were unsuitable for meta-analysis. RESULTS: Initial searches identified 660 papers in total. Five met the inclusion criteria. Two studies showed moderate agreement between paramedics and ED physicians for GCS assessment. The PTS overtriage rate was 10% and the undertriage rate was 62%, while the triage tape had an overtriage rate of 18% and an undertriage rate of 68%. Pre-hospital GCS had 86.67% sensitivity and 71.43% specificity [95% CI]: 0.74-0.96 for neurosurgically significant TBI. CONCLUSION: Low level of GCS agreement and poor diagnostic accuracy may cause further harm to the patient; thus, further studies are recommended to improve the prehospital management of children with head injuries.


Subject(s)
Brain Injuries, Traumatic , Craniocerebral Trauma , Physicians , Humans , Child , Triage , Reproducibility of Results , Brain Injuries, Traumatic/diagnosis
2.
BMJ Open ; 13(3): e068555, 2023 03 07.
Article in English | MEDLINE | ID: mdl-36882243

ABSTRACT

INTRODUCTION: Traumatic brain injury (TBI) is a major global health burden that results in disability and loss of health. Identifying those patients who require specialist neuroscience care can be challenging due to the low accuracy of existing prehospital trauma triage tools. Despite the widespread use of decision aids to 'rule out' TBI in hospitals, they are not widely used in the prehospital environment. We aim to provide a snapshot of current prehospital practices in the UK, and to explore facilitators and challenges that may be encountered when adopting new tools for decision support. METHODS AND ANALYSIS: A mixed-methods study will be conducted using a convergent design approach. In the first phase, we will conduct a national survey of current practice in which every participating ambulance service in the UK will receive an online questionnaire, and only one response is required. In the second phase, semistructured interviews will be conducted to explore the perceptions of ambulance service personnel regarding the implementation of new triage methods that may enhance triage decisions. The survey questions and the interview topic guide were piloted and externally reviewed. Quantitative data will be summarised using descriptive statistics; qualitative data will be analysed thematically. ETHICS AND DISSEMINATION: This study has been approved by the Health Research Authority (REC reference 22/HRA/2035). Our findings may inform the design of future care pathways and research as well as identify challenges and opportunities for future development of prehospital triage tools for patients with suspected TBI. Our findings will be published in peer-reviewed journals, relevant national and international conferences, and will be included in a PhD thesis.


Subject(s)
Brain Injuries, Traumatic , Triage , Humans , Brain Injuries, Traumatic/diagnosis , Brain Injuries, Traumatic/therapy , Patients , Ambulances , Critical Pathways
3.
J Trace Elem Med Biol ; 71: 126965, 2022 May.
Article in English | MEDLINE | ID: mdl-35278998

ABSTRACT

BACKGROUND: Mercury is a relentless pollutant, and its toxicity contributes to significant health problems due to exposure to the environment. The present study has determined the impact of flaxseed oil on mercuric chloride (HgCl2)-mediated hepatic oxidative toxicity in rats. METHODS: Twenty-four healthy male Wistar rats were divided into four groups with six animals in each group. Group-A was the Control group treated with saline; Group-B received 1.0 ml oral dosage of flaxseed oil; Group-C was given 200 µl intraperitoneal injection of HgCl2, and Group-D received 1.0 ml oral dosage of flaxseed oil (one hour after treatment with 200 µl intraperitoneal injection of HgCl2. RESULTS: Mercuric chloride (HgCl2) increased the production of malondialdehyde (MDA), reactive oxygen species (ROS), glutathione (GSH), and the concentration of HgCl2 in the liver tissue with a simultaneous decrease in the activities of Superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). Furthermore, serum HgCl2 elevated the activity of alanine transaminase (ALT) and Lactate dehydrogenase (LDH). Histopathological changes showed that liver injury was caused by mercuric chloride. Treatment with flaxseed oil ameliorated ROS production and reversed enzymes in serum and liver. Also, a noticeable improvement was observed in all the histopathological characteristics in the rats. CONCLUSIONS: The findings of this study concluded that flaxseed oil had an outstanding remedial effect on mercuric chloride-mediated hepatic cytotoxicity.


Subject(s)
Antioxidants , Liver Diseases , Rats , Male , Animals , Antioxidants/metabolism , Linseed Oil/pharmacology , Linseed Oil/therapeutic use , Linseed Oil/metabolism , Mercuric Chloride/toxicity , Rats, Wistar , Reactive Oxygen Species/metabolism , Oxidative Stress , Lipid Peroxidation , Liver Diseases/metabolism , Liver/metabolism , Glutathione/metabolism
4.
Injury ; 53(6): 2060-2068, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35190184

ABSTRACT

INTRODUCTION: Prehospital care providers are usually the first responders for patients with traumatic brain injury (TBI). Early identification of patients with TBI enables them to receive trauma centre care, which improves outcomes. Two recent systematic reviews concluded that prehospital triage tools for undifferentiated major trauma have low accuracy. However, neither review focused specifically on patients with suspected TBI. Therefore, we aimed to systematically review the existing evidence on the diagnostic performance of prehospital triage tools for patients with suspected TBI. METHODS: A comprehensive search of the current literature was conducted using Medline, EMBASE, CINAHL Plus and the Cochrane library (inception to 1st June 2021). We also searched Google Scholar, OpenGrey, pre-prints (MedRxiv) and dissertation databases. We included all studies published in English language evaluating the accuracy of prehospital triage tools for TBI. We assessed methodological quality and risk of bias using a modified Quality Assessment of Diagnostic Studies (QUADAS-2) tool. Two reviewers independently performed searches, screened titles and abstracts and undertook methodological quality assessments. Due to the heterogeneity in the population of interest and prehospital triage tools used, a narrative synthesis was undertaken. RESULTS: The initial search identified 1787 articles, of which 8 unique eligible studies met the inclusion criteria (5 retrospective, 2 prospective, 1 mixed). Overall, sensitivity of triage tools studied ranged from 19.8% to 87.9% for TBI identification. Specificity ranged from 41.4% to 94.4%. Two decision tools have been validated more than once: HITS-NS (2 studies, sensitivity 28.3-32.6%, specificity 89.1-94.4%) and the Field Triage Decision Scheme (4 studies, sensitivity 19.8-64.5%, specificity 77.4%-93.1%). Existing tools appear to systematically under-triage older patients. CONCLUSION: Further efforts are needed to improve and optimise prehospital triage tools. Consideration of additional predictors (e.g., biomarkers, clinical decision aids and paramedic judgement) may be required to improve diagnostic accuracy.


Subject(s)
Brain Injuries, Traumatic , Triage , Brain Injuries, Traumatic/diagnosis , Humans , Prospective Studies , Retrospective Studies , Trauma Centers
5.
Front Oncol ; 11: 622470, 2021.
Article in English | MEDLINE | ID: mdl-33796459

ABSTRACT

Cancer is one of the major leading causes of death worldwide. Designing the new anticancer drugs is remained a challenging task due to ensure complexicity of cancer etiology and continuosly emerging drug resistance. Glycolipid biosurfactants are known to possess various biological activities including antimicrobial, anticancer and antiviral properties. In the present study, we sought to decipher the mechanism of action of the glycolipids (lactonic-sophorolipd, acidic-sophorolipid, glucolipid, and bolalipid) against cancer cells using lung cancer cell line (A549), breast cancer cell line (MDA-MB 231), and mouse skin melanoma cell line (B16F10). Scratch assay and fluorescence microscopy revealed that glycolipids inhibit tumorous cell migration possibly by inhibiting actin filaments. Fluorescence activated cell sorter (FACS) analysis exhibited that lactonic sophorolipid and glucolipid both induced the reactive oxygen species, altered the mitochondrial membrane potential (ΔΨ) and finally led to the cell death by necrosis. Furthermore, combinatorial effect of lactonic-sophorolipd and glucolipid demonstrated synergistic interaction on A549 cell line whereas additive effect on MDA-MB 231 and B16F10 cell lines. Our study has highlighted that lactonic-sophorolipd and glucolipid could be useful for developing new anticancer drugs either alone or in combination.

6.
Mol Biol Rep ; 46(6): 6171-6179, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31493285

ABSTRACT

The toxicity of heavy metals such as mercury (Hg) in humans and animals is well documented. The kidney is the primary deposition site of inorganic-Hg and target organ of its toxicity. The present study investigated the protective efficacy of flaxseed lignan-Secoisolariciresinol diglucoside (SDG) on nephrotoxicity induced by mercuric chloride (HgCl2). Rats were intraperitoneally injected with HgCl2 (2 mg/kg/day) and renal toxicity was induced. Subcutaneous administration of rats with SDG (5 mg/kg/day) as a pre-treatment caused a significant reversal of HgCl2 induced increase in blood urea, creatinine, glutathione s-transferase and catalase (CAT). On the other hand, administration of SDG with HgCl2 restored normal levels of albumin and superoxide dismutase (SOD). Histological examination of kidneys confirmed that pre-treatment of SDG before HgCl2 administration significantly reduced its pathological effects. Thus, the results of the present investigation suggest that SDG can significantly reduce renal damage, serum and tissue biochemical profiles caused by HgCl2 induced nephrotoxicity. Hence, SDG may be recommended for clinical trials in the treatment of kidney disorders caused by exposure to Hg.


Subject(s)
Butylene Glycols/pharmacology , Flax/chemistry , Glucosides/pharmacology , Kidney/drug effects , Lignans/pharmacology , Mercuric Chloride/toxicity , Plant Extracts/pharmacology , Protective Agents/pharmacology , Animals , Antioxidants/metabolism , Biomarkers , Butylene Glycols/chemistry , Chromatography, High Pressure Liquid , Glucosides/chemistry , Glutathione Transferase/metabolism , Kidney/metabolism , Kidney/pathology , Lignans/chemistry , Male , Molecular Structure , Oxidative Stress/drug effects , Plant Extracts/chemistry , Protective Agents/chemistry , Rats
7.
Oncol Lett ; 18(3): 3399-3406, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31452820

ABSTRACT

Discovering the underlying signalling pathways that control cancer cells is crucial for understanding their biology and to develop therapeutic regimens. Thus, the aim of the present study was to determine the effect of Cripto-1 on pathways controlling glioblastoma (GBM) cell function. To this end, changes in protein phosphorylation in cells overexpressing Cripto-1 were analysed using the Kyoto Encyclopedia of Genes and Genomes pathway analysis tool, as well as the Uniprot resource to identify the functions of Cripto-1-dependent phosphorylated proteins. This revealed that proteins affected by Cripto-1 overexpression are involved in multiple signalling pathways. The mitogen-activated protein kinase (MAPK), focal adhesion (FA) and ErbB pathways were found to be enriched by Cripto-1 overexpression with 35, 27 and 24% of pathway proteins phosphorylated, respectively. These pathways control important cellular processes in cancer cells that correlate with the observed functional changes described in earlier studies. More specifically, Cripto-1 may regulate MAPK cellular proliferation and survival pathways by activating epithelial growth factor receptor (EGFR; Ser1070) or fibroblast GFR1 (Tyr654). Its effect on cellular proliferation and survival could be mediated through Src (Tyr418), FA kinase (FAK; Tyr396), p130CAS (Tyr410), c-Jun (Ser63), Paxillin (PXN; Tyr118) and BCL2 (Thr69) of the FA pathway. Cripto-1 may also control cellular motility and invasion by activating Src (Tyr418), FAK (Tyr396) and PXN (Tyr118) of the FA pathway. However, Cripto-1 regulation of cellular invasion and migration might be not limited to the FA pathway, it may also control these cellular mechanisms through signalling via EGFR (Ser1070)/Her2 (Tyr877) to mediate the Src (Tyr418) and FAK (Tyr396) cascade activation of the ErbB signalling pathway. Angiogenesis could be mediated by Cripto-1 by activating c-Jun (Ser63) through EGFR (Ser1070)/Her2 (Tyr877) of the ErbB pathway. To conclude, the present study has augmented and enriched our current knowledge on the crucial roles that Cripto-1 may play in controlling different cellular mechanisms in GBM cells.

8.
Oncol Lett ; 18(2): 1657-1668, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31423233

ABSTRACT

MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression by suppressing the target mRNA and inhibiting translation in order to regulate multiple biological processes. miRNAs play important roles as oncogenes or tumor suppressors in the development of various types of human cancer. The regulation of mammalian target of rapamycin (mTOR) by miRNAs has been studied in several types of cancer, including colorectal cancer (CRC). However, to the best of our knowledge, only limited information regarding the function of miRNAs in human CRC is available. In the present study, the expression of 22 miRNAs in CRC cell lines were investigated in regard to key genes in the mTOR pathway. Initially, it was revealed that mTOR, regulatory-associated protein of mTOR complex I and rapamycin-intensive companion of mTOR were overexpressed in CRC cell lines when compared with a normal colorectal cell line. Subsequently, putative miRNA-mRNA associations were identified via multiple miRNA target prediction programs. The expression levels for the candidate miRNAs were validated using quantitative real-time polymerase chain reaction. Expression analysis revealed that, among 20 miRNAs, five miRNAs (miR-496, miR-1185, miR-654, miR-3183 and miR-495) exhibited significant downregulation in association with the mTOR signaling pathway. Taken together, the results from the present study suggest that several miRNAs that are associated with CRC, with possible roles in mTOR signaling, may have potential therapeutic or diagnostic benefits in CRC treatment.

9.
J Cell Biochem ; 120(5): 7412-7427, 2019 May.
Article in English | MEDLINE | ID: mdl-30426531

ABSTRACT

Cripto-1 has been implicated in a number of human cancers. Although there is high potential for a role of Cripto-1 in glioblastoma multiforme (GBM) pathogenesis and progression, few studies have tried to define its role in GBM. These studies were limited in that Cripto-1 expression was not studied in detail in relation to markers of cancer initiation and progression. Therefore, these correlative studies allowed limited interpretation of Criptos-1's effect on the various aspects of GBM development using the U87 GBM cell line. In this study, we sought to delineate the role of Cripto-1 in facilitating pathogenesis, stemness, proliferation, invasion, migration and angiogenesis in GBM. Our findings show that upon overexpressing Cripto-1 in U87 GBM cells, the stemness markers Nanog, Oct4, Sox2, and CD44 increased expression. Similarly, an increase in Ki67 was observed demonstrating Cripto-1's potential to induce cellular proliferation. Likewise, we report a novel finding that increased expression of the markers of migration and invasion, Vimentin and Twist, correlated with upregulation of Cripto-1. Moreover, Cripto-1 exposure led to VEGFR-2 overexpression along with higher tube formation under conditions promoting endothelial growth. Taken together our results support a role for Cripto-1 in the initiation, development, progression, and maintenance of GBM pathogenesis. The data presented here are also consistent with a role for Cripto-1 in the re-growth and invasive growth in GBM. This highlights its potential use as a predictive and diagnostic marker in GBM as well as a therapeutic target.

10.
Oncol Rep ; 40(5): 2690-2697, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30226622

ABSTRACT

Cancer cells have been known to overexpress the epidermal growth factor receptor (EGFR) and hence relevant multiple­targeted therapies have been developed, with a recent clinical application of the antibody­mediated inhibition of the EGFR. However, this strategy is not useful in cancer cells with mutations in KRAS; a GTPase downstream of EGFR which constitutively activates the pathway without EGF stimulation. Furthermore, mutations in EGFR also reduce the binding of monoclonal antibodies and thereby render them ineffective. In the present study, we designed a chimeric EGF protein fused to the truncated N­terminal domain fragment of Pseudomonas aeruginosa exotoxin A (EGF­ETA), which has ADP­ribosylation activity and induces apoptosis. The EGF­ETA protein was expressed in E. coli as a His­tagged fusion. Our results showed that EGF­ETA significantly inhibited the proliferation of EGFR­positive A431 epidermoid carcinoma (IC50 27 ng/ml) and HN5 head and neck squamous cell carcinoma (IC50 36 ng/ml) cells. However, its effect on cancer cells with little or no EGFR expression was limited (A549­IC50 1,000 ng/ml; MCF­7­IC50 >10,000 ng/ml). Compared to cetuximab, EGF­ETA was highly potent in its killing capacity of HN5 cancer cells at 1,000 ng/ml, while cetuximab had little effect at 1,000 ng/ml. Furthermore, EGF­ETA was just as potent in HCT116 (KRAS G13D) and SW480 (KRAS G12V) colon cancer cell lines harbouring KRAS hyperactivating mutations when compared to KRAS wild­type HT29 colon cancer cells. Finally, co­incubation of EGF­ETA with an anti­EGF antibody abrogated its effect on the EGFR­positive A431 cells. Our results show that the chimeric EGF­ETA toxin is extremely effective against EGFR­positive cancers and raises the potential to further develop this chimera for use in targeting EGFR­positive tumours resistant to monoclonal antibodies.


Subject(s)
ADP Ribose Transferases/pharmacology , Bacterial Toxins/pharmacology , Carcinoma, Squamous Cell/drug therapy , Epidermal Growth Factor/pharmacology , Exotoxins/pharmacology , Virulence Factors/pharmacology , ADP Ribose Transferases/genetics , ADP Ribose Transferases/immunology , Antibodies, Anti-Idiotypic/pharmacology , Apoptosis/drug effects , Apoptosis/immunology , Bacterial Toxins/genetics , Bacterial Toxins/immunology , Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/immunology , Carcinoma, Squamous Cell/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Cetuximab/pharmacology , Epidermal Growth Factor/genetics , Epidermal Growth Factor/immunology , ErbB Receptors/antagonists & inhibitors , ErbB Receptors/genetics , ErbB Receptors/immunology , Exotoxins/genetics , Exotoxins/immunology , Humans , Ligands , Proto-Oncogene Proteins p21(ras)/genetics , Pseudomonas aeruginosa/genetics , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/immunology , Recombinant Fusion Proteins/pharmacology , Squamous Cell Carcinoma of Head and Neck , Virulence Factors/genetics , Virulence Factors/immunology , Pseudomonas aeruginosa Exotoxin A
11.
Oncol Rep ; 40(2): 1083-1092, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29845289

ABSTRACT

The mammalian target of rapamycin (mTOR), a downstream effector of the PI3K/Akt signalling pathway, is a critical regulator of cell metabolism, growth and survival in response to oncogenic factors. Activation of mTOR frequently occurs in human tumours making it a crucial and validated target in the treatment of cancer. mTOR inhibitors such as rapamycin and its analogues decrease cancer progression in experimental models including colorectal cancer (CRC). Recently, the second generation ATP­competitive mTOR kinase (such as PP242) and dual mTOR/PI3K (such as NVP­BEZ235) inhibitors have entered clinical trials as anticancer agents. However, in CRC, the efficacy of these novel drugs needs to be fully investigated. In the present study, we examined five human CRC cell lines, HT29, HCT116, SW480, SW620 and CSC480 to evaluate their sensitivity to three mTOR inhibitors, RAD001, PP242 and NVP­BEZ235. We observed that compared to RAD001 and PP242, NVP­BEZ235 markedly reduced cell proliferation of CRC cells. Furthermore, we found that the reduced cell proliferation caused by NVP­BEZ235 was not achieved through the disruption of mitochondrial potential. Using an mTOR­specific signalling pathway phospho array we revealed that NVP­BEZ235 significantly decreased phosphorylation of 4E­BP1 (Thr70), the downstream target of mTORC1. In addition, NVP­BEZ235 decreased phosphorylation of AKT (Ser473), the downstream target of mTORC2. Immunoblotting analysis revealed that NVP­BEZ235 effectively inhibited 4E­BP1 phosphorylation, while PP242 had a weak inhibitory effect. However, PP242 and NVP­BEZ235 decreased AKT levels in all cell lines. RAD001 demonstrated no effect on 4E­BP1. Based on the above­mentioned results, the dual PI3K/mTOR and ATP­competitive mTOR inhibitors have demonstrated high potential for targeting the mTOR pathway in CRC.


Subject(s)
Adaptor Proteins, Signal Transducing/antagonists & inhibitors , Cell Proliferation/drug effects , Colorectal Neoplasms/drug therapy , Imidazoles/pharmacology , Phosphoinositide-3 Kinase Inhibitors , Phosphoproteins/antagonists & inhibitors , Quinolines/pharmacology , TOR Serine-Threonine Kinases/antagonists & inhibitors , Antineoplastic Agents/pharmacology , Cell Cycle Proteins , Cell Line, Tumor , Colorectal Neoplasms/metabolism , Everolimus/pharmacology , HCT116 Cells , HT29 Cells , Humans , Indoles/pharmacology , Phosphorylation/drug effects , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins c-akt/metabolism , Purines/pharmacology , Signal Transduction/drug effects
12.
Oncol Rep ; 39(6): 2881-2891, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29693155

ABSTRACT

To date two questions that remain unanswered regarding cancer are the following: i) how is it initiated, and ii) what is the role that cancer stem cells (CSCs) play in the disease process? Understanding the biology of CSCs and how they are generated is pivotal for the development of successful treatment regimens. To date, the lack of a representative cell model has prevented the successful identification and eradication of CSCs in vivo. The current methods of CSC identification are dependent on the protocol used to generate these cells, which has introduced variation and made the identification process more complicated. Furthermore, the list of possible markers is increasing in complexity. This is further confounded by the fact that there is insufficient information to determine whether the cells these markers detect are truly self­renewing stem cells or, instead, progenitor cells. In the present study, we investigated a novel cell line model, CSC480, which can be employed to assess CSC markers and for testing novel therapeutic regimens. CSC480 cells have been revealed to express markers of CSCs such as CD44, ALDH1 and Sox2, that have lower expression in the SW480 cell line. CSC480 cells also expressed higher levels of the cancer resistance marker, ABCG2 and had higher proliferative and growth capacity than SW480 cells. In the present study, we also evaluated a novel approach to identify different cell types present in heterogeneous cancer cell populations according to their proliferative ability using the proliferation marker 5­ethynyl­2'­deoxyuridine (EdU). Furthermore, using EdU, we identified dormant cells with a modified label­retaining cell (LRC) protocol. Through this novel LRC method, we assessed newly discovered markers of stemness to ascertain their capability to identify quiescent from dividing CSCs. In conclusion, the CSC480 cell line was an important model to be used in unravelling the underlying mechanisms that control fast­dividing and partially self­renewing stem cells (SCs) that may give rise to cancer.


Subject(s)
Biomarkers, Tumor/metabolism , Colonic Neoplasms/pathology , Down-Regulation , Neoplastic Stem Cells/pathology , Aldehyde Dehydrogenase 1 Family , Cell Line, Tumor , Cell Proliferation , Colonic Neoplasms/metabolism , Drug Resistance, Neoplasm , Gene Expression Regulation, Neoplastic , Humans , Hyaluronan Receptors/metabolism , Isoenzymes/metabolism , Neoplastic Stem Cells/metabolism , Retinal Dehydrogenase/metabolism , SOXB1 Transcription Factors/metabolism , Spheroids, Cellular/cytology , Spheroids, Cellular/metabolism
13.
Hum Pathol ; 44(10): 2089-96, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23773481

ABSTRACT

This study investigated the clinicopathologic roles of mammalian target of rapamycin (mTOR) expression and its relationship to carcinogenesis and tumor progression in a colorectal adenoma-adenocarcinoma model. Two colon cancer cell lines with different pathologic stages (SW480 and SW48) and 1 normal colonic epithelial cell line (FHC) were used, in addition to 119 colorectal adenocarcinomas and 32 adenomas. mTOR expression profiles at messenger RNA (mRNA) and protein levels were investigated in the cells and tissues using real-time quantification polymerase chain reaction and immunohistochemistry. The findings were correlated with the clinicopathologic features of the tumors. The colon cell line from stage III cancer (SW48) showed higher expression of mTOR mRNA than that from stage II cancer (SW480). At the tissue level, mTOR showed higher mRNA and protein expression in colorectal carcinoma than in adenoma. The mRNA and protein expression was correlated with each other in approximately one-third of the carcinomas and adenomas. High levels of mTOR mRNA expression were noted more in carcinoma or adenoma arising from the distal portion of the large intestine (P = .025 and .019, respectively). Within the colorectal cancer population, a high level of expression of mTOR mRNA was related to the presence of lymph node metastases (P = .031), advanced pathologic stage (P = .05), and presence of persistent disease or tumor recurrence (P = .035). To conclude, the study has indicated that mTOR is likely to be involved in the development and progression of colorectal cancer and is linked to cancer initiation, invasiveness, and progression.


Subject(s)
Adenocarcinoma/secondary , Adenoma/pathology , Colorectal Neoplasms/pathology , Gene Expression Regulation, Neoplastic , TOR Serine-Threonine Kinases/genetics , Adenocarcinoma/genetics , Adenocarcinoma/metabolism , Adenoma/genetics , Adenoma/metabolism , Adult , Aged , Aged, 80 and over , Biomarkers, Tumor/metabolism , Cell Line, Tumor , Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , Female , Humans , Intestinal Mucosa/metabolism , Intestinal Mucosa/pathology , Lymph Nodes/pathology , Lymphatic Metastasis , Male , Middle Aged , Neoplasm Invasiveness , Neoplasm Proteins/metabolism , Neoplasm Staging , RNA, Messenger/metabolism , TOR Serine-Threonine Kinases/metabolism
14.
Int J Mol Sci ; 14(2): 3874-900, 2013 Feb 13.
Article in English | MEDLINE | ID: mdl-23434669

ABSTRACT

The mammalian target of rapamycin (mTOR) is a critical regulator of many fundamental features in response to upstream cellular signals, such as growth factors, energy, stress and nutrients, controlling cell growth, proliferation and metabolism through two complexes, mTORC1 and mTORC2. Dysregulation of mTOR signalling often occurs in a variety of human malignant diseases making it a crucial and validated target in the treatment of cancer. Tumour cells have shown high susceptibility to mTOR inhibitors. Rapamycin and its derivatives (rapalogs) have been tested in clinical trials in several tumour types and found to be effective as anticancer agents in patients with advanced cancers. To block mTOR function, they form a complex with FKBP12 and then bind the FRB domain of mTOR. Furthermore, a new generation of mTOR inhibitors targeting ATP-binding in the catalytic site of mTOR showed potent and more selective inhibition. More recently, microRNAs (miRNA) have emerged as modulators of biological pathways that are essential in cancer initiation, development and progression. Evidence collected to date shows that miRNAs may function as tumour suppressors or oncogenes in several human neoplasms. The mTOR pathway is a promising target by miRNAs for anticancer therapy. Extensive studies have indicated that regulation of the mTOR pathway by miRNAs plays a major role in cancer progression, indicating a novel way to investigate the tumorigenesis and therapy of cancer. Here, we summarize current findings of the role of mTOR inhibitors and miRNAs in carcinogenesis through targeting mTOR signalling pathways and determine their potential as novel anti-cancer therapeutics.

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