GAEC1 (gene amplified in oesophageal cancer 1) is a transforming oncogene with tumorigenic potential observed in both oesophageal squamous cell carcinoma and colorectal cancer. Nonetheless, there has been a lack of study done on this gene to understand how this gene exert its oncogenic properties in cancer. This study aims to identify novel mutation sites in GAEC1. To do so, seventy-nine matched colorectal cancers were tested for GAEC1 mutation via Sanger sequencing. The mutations noted were investigated for the correlations with the clinicopathological parameters of the patients with the cancer. Additionally, GAEC1 copy number aberration (CNA), mRNA and protein expression were determined with the use of droplet digital (dd) polymerase chain reaction (PCR), real-time PCR and Western blot (confirmed with immunofluorescence analysis). GAEC1 mutation was noted in 8.8% (n = 7/79) of the cancer tissues including one missense mutation, four loss of heterozygosity (LOH) and two substitutions. These mutations were significantly associated with cancer perforation (p = 0.021). GAEC1 mutation is frequently associated with increased GAEC1 protein expression. Nevertheless, GAEC1 mRNA and protein are only weakly associated. Taken together, GAEC1 mutation affects GAEC1 expression and is associated with poorer clinical outcomes. This further strengthens the role of GAEC1 as an oncogene.
The current study aims to evaluate for the first time the inhibitory roles of miR-205 in the pathogenesis of anaplastic thyroid carcinoma. In addition, we investigated the mechanisms by which miR-205 regulates angiogenesis and epithelial-to-mesenchymal transition (EMT) in cancer. Two anaplastic thyroid carcinoma cell lines were transfected with the expression vector pCMV-MIR-205. Selected markers of angiogenesis and EMT including vascular endothelial growth factor A (VEGF-A) and zinc finger E-box-binding homeobox 1 (ZEB1) were investigated by Western blot. The interaction of miR-205 expression with EMT and angiogenesis were also investigated by assessment of matrix metalloproteinases 2 and 9 (MMP2 and MMP 9), SNAI1 (Snai1 family zinc finger 1), vimentin, E-cadherin and N-cadherin. The function of miR-205 was further tested with VEGF enzyme-linked immunosorbent assay (ELISA), wound healing, invasion and tube formation assays. Using an animal model, we studied the association of miR-205 with angiogenesis, proliferation and invasion. The following results were obtained. Permanent overexpression of miR-205 significantly suppressed angiogenesis and EMT by simultaneously targeting VEGF-A, ZEB1 and downstream products. Ectopic expression of miR-205 in cancer cells led to decreased migration, invasion and tube formation of endothelial cells. In addition, inhibition of tumour growth, vascularisation and invasion were noted in the mouse tumour xenografts. Our findings provide insights into simultaneous regulatory role of miR-205 in the pathogenesis of anaplastic thyroid carcinoma by suppressing both angiogenesis and EMT. This may open avenues to exploit miR-205 as an alternative cancer therapeutic strategy in the future.
AIMS:To investigate the expression pattern of microRNA-451 (miR-451) in patients with colorectal carcinoma and correlate with the expression of its target gene MIF (macrophage migration inhibitory factor).METHODS:Matched cancer and non-cancer fresh frozen tissues were prospectively collected from 70 patients (35 men and 35 women) who underwent resection of colorectal adenocarcinoma. These tissues collected were extracted for miR and complementary DNA conversion. Then, miR-451 expressions in these tissues were measured by quantitative real-time PCR. The expression was correlated with clinical and pathological parameters of these patients. In addition, paraffin blocks of 10 colorectal carcinomas with lowest expression of miR-451 were used for the study of MIF protein expression by immunohistochemistry.RESULTS:miR-451 was downregulated in majority of the colorectal cancer tissues when compared with their matched normal tissues (84.3%, n=59/70). Downregulation of miR-451 correlates significantly with presence of coexisting adenoma (91.4%, p=0.025). In addition, persistence of cancer or cancer recurrence after surgery showed significant correlation with downregulation of miR-451 (80% vs 0%; p=0.028). There is no significant correlation between miR-451 expression and age, gender of the patients as well as size, grades, pathological stages, presence of lymphovascular permeation, perineural invasion and microsatellite instability status of the colorectal carcinoma (p>0.05). Majority of the cases (80%) with low expression of miR-451 showed high levels of MIF protein expression confirming the inverse relationship between miR-451 and MIF expressions.CONCLUSIONS:The results showed that miR-451 could play a role in development and progression of colorectal cancer and likely by targeting MIF.
Cancer cells exhibit alterations in many cellular processes, including oxygen sensing and energy metabolism. Glycolysis in non-oxygen condition is the main energy production process in cancer rather than mitochondrial respiration as in benign cells. Genetic and epigenetic alterations of Krebs cycle enzymes favour the shift of cancer cells from oxidative phosphorylation to anaerobic glycolysis. Mutations in genes encoding aconitase, isocitrate dehydrogenase, succinate dehydrogenase, fumarate hydratase, and citrate synthase are noted in many cancers. Abnormalities of Krebs cycle enzymes cause ectopic production of Krebs cycle intermediates (oncometabolites) such as 2-hydroxyglutarate, and citrate. These oncometabolites stabilize hypoxia inducible factor 1 (HIFI), nuclear factor like 2 (Nrf2), inhibit p53 and prolyl hydroxylase 3 (PDH3) activities as well as regulate DNA/histone methylation, which in turn activate cell growth signalling. They also stimulate increased glutaminolysis, glycolysis and production of reactive oxygen species (ROS). Additionally, genetic alterations in Krebs cycle enzymes are involved with increased fatty acid beta-oxidations and epithelial mesenchymal transition (EMT) induction. These altered phenomena in cancer could in turn promote carcinogenesis by stimulating cell proliferation and survival. Overall, epigenetic and genetic changes of Krebs cycle enzymes lead to the production of oncometabolite intermediates, which are important driving forces of cancer pathogenesis and progression. Understanding and applying the knowledge of these mechanisms opens new therapeutic options for patients with cancer. (C) 2017 Elsevier B.V. and Societe Francaise de Biochimie et Biologie Moleculaire (SFBBM). All rights reserved.
Migraine is a brain disorder characterized by a piercing headache which affects one side of the head, located mainly at the temples and in the area around the eye. Migraine imparts substantial suffering to the family in addition to the sufferer, particularly as it affects three times more women than men and is most prevalent between the ages of 25 and 45, the years of child rearing. Migraine typically occurs in individuals with a genetic predisposition and is aggravated by specific environmental triggers. Attempts to study the biochemistry of migraine began as early as the 1960s and were primarily directed at serotonin metabolism after an increase of 5-hydroxyindoleacetic acid (5-HIAA), the main metabolite of serotonin was observed in urine of migraineurs. Genetic and biochemical studies have primarily focused on the neurotransmitter serotonin, considering receptor binding, transport and synthesis of serotonin and have investigated serotonergic mediators including enzymes, receptors as well as intermediary metabolites. These studies have been mainly assayed in blood, CSF and urine as the most accessible fluids. More recently PET imaging technology integrated with a metabolomics and a systems biology platform are being applied to study serotonergic biology. The general trend observed is that migraine patients have alterations of neurotransmitter metabolism detected in biological fluids with different biochemistry from controls, however the interpretation of the biological significance of these peripheral changes is unresolved. In this review we present the biology of the serotonergic system and metabolic routes for serotonin and discuss results of biochemical studies with regard to alterations in serotonin in brain, cerebrospinal fluid, saliva, platelets, plasma and urine of migraine patients.
Cancer cells exhibit alterations in many cellular processes, including oxygen sensing and energy metabolism. Glycolysis in non-oxygen condition is the main energy production process in cancer rather than mitochondrial respiration as in benign cells. Genetic and epigenetic alterations of Krebs cycle enzymes favour the shift of cancer cells from oxidative phosphorylation to anaerobic glycolysis. Mutations in genes encoding aconitase, isocitrate dehydrogenase, succinate dehydrogenase, fumarate hydratase, and citrate synthase are noted in many cancers. Abnormalities of Krebs cycle enzymes cause ectopic production of Krebs cycle intermediates (oncometabolites) such as 2-hydroxyglutarate, and citrate. These oncometabolites stabilize hypoxia inducible factor 1 (HIF1), nuclear factor like 2 (Nrf2), inhibit p53 and prolyl hydroxylase 3 (PDH3) activities as well as regulate DNA/histone methylation, which in turn activate cell growth signalling. They also stimulate increased glutaminolysis, glycolysis and production of reactive oxygen species (ROS). Additionally, genetic alterations in Krebs cycle enzymes are involved with increased fatty acid β-oxidations and epithelial mesenchymal transition (EMT) induction. These altered phenomena in cancer could in turn promote carcinogenesis by stimulating cell proliferation and survival. Overall, epigenetic and genetic changes of Krebs cycle enzymes lead to the production of oncometabolite intermediates, which are important driving forces of cancer pathogenesis and progression. Understanding and applying the knowledge of these mechanisms opens new therapeutic options for patients with cancer.
We aim to investigate the expression profiles of galectin family genes (galectins-1, 2, 3, 4, 7, 8, 9, 10, and 11) in colorectal carcinomas. Messenger RNA (mRNA) expression of galectin family members (1, 2, 3, 4, 7, 8, 9, 10, and 12) was analyzed by real-time polymerase chain reaction in colorectal tissues from 201 patients (54 noncancer colorectal tissues, 49 adenomas, and 98 adenocarcinomas). Galectin-1 and galectin-3 protein expressions were determined by immunohistochemistry. In general, high galectin mRNA expression was noted in colorectal carcinomas in early stages of their pathogenesis. Significant differences in galectins-2, 3, 7, 8, and 10 mRNA expression were associated with pathologic stages (P<.05). Increased prevalence of galectins-2, 7, 8, and 10 mRNA overexpression was noted in nonmetastatic colorectal carcinomas (P<.05). Galectin-1 and galectin-3 proteins were present in the nucleus and cytoplasm of the colorectal tissues and expressed significantly higher in colorectal carcinomas when compared to colorectal adenomas (61% and 95%, respectively). Patients with colorectal carcinoma with high levels of galectin-3 mRNA and protein expression showed better prognosis (P=.052). To conclude, many novel correlations between the deregulation of galectin family genes and various clinicopathological features in colorectal adenocarcinoma were noted. Overexpression of galectins at the mRNA level and proteins were predominant in earlier stages of colorectal carcinomas. These altered expression patterns of galectin genes suggest the multifunctional role of galectin genes in the regulation of colorectal cancer development, progression, and metastasis.
There are emerging data to suggest that microRNAs (miRNAs) have significant roles in regulating the function of normal cells and cancer stem cells (CSCs). This review aims to analyse the roles of miRNAs in the regulation of colon CSCs through their interaction with various signalling pathways. Studies showed a large number of miRNAs that are reported to be deregulated in colon CSCs. However, few of the studies available were able to outline the function of miRNAs in colon CSCs and uncover their signalling pathways. From those miRNAs, which are better described, miR-21 followed by miR-34, miR-200 and miR-215 are the most reported miRNAs to have roles in colon CSC regulation. In particular, miRNAs have been reported to regulate the stemness features of colon CSCs mainly via Wnt/B-catenin and Notch signalling pathways. Additionally, miRNAs have been reported to act on processes involving CSCs through cell cycle regulation genes and epithelial-mesenchymal transition. The relative paucity of data available on the significance of miRNAs in CSCs means that new studies will be of great importance to determine their roles and to identify the signalling pathways through which they operate. Such studies may in future guide further research to target these genes for more effective cancer treatment. miRNAs were shown to regulate the function of cancer stem cells in large bowel cancer by targeting a few key signalling pathways in cells.
MicroRNA-126 (miR-126) expression has been shown to be associated with angiogenesis. The aim of the current study is to evaluate the functional roles of miR-126 in dysregulation of VEGF expression and cancer progression in thyroid carcinomas. The expression of VEGF-A and miR-126 were measured in 101 thyroid carcinomas tissues (including 51 conventional papillary thyroid carcinoma, 37 follicular variant of papillary thyroid carcinoma, and 13 undifferentiated thyroid carcinomas), 13 matched lymph nodes with metastatic thyroid carcinoma, 21 benign thyroid tissues, and 5 thyroid carcinoma cell lines (both papillary and undifferentiated carcinomas). Then, exogenous miR-126 was transfected, and the expressions of VEGF-A were determined (Western blot technique). Proliferation assay, cell cycle analysis, and apoptosis assays were used to evaluate the role of miR-126 in these events. Significant underexpression of miR-126 levels in thyroid cancer tissues and cell lines was detected using real-time polymerase chain reaction. Introducing exogenous miR-126 into the cancer cell lines resulted in a significant reduction of VEGF-A protein expression. Marked inhibition in proliferation, cell cycle arrest in G0-G1, and promotion of total apoptosis were also noted. The modulatory role of miR-126 on expression of VEGF-A and its tumor suppressive roles were demonstrated for the first time in thyroid cancer. The current experiments provided specific information on the functional consequences of VEGF manipulation via microRNA on cancer.
The aim of our study was to inhibit BRAF kinase expression and investigate its effect on cellular functions in thyroid carcinomas. 8505C (BRAF V600E/V600E) undifferentiated thyroid carcinoma cell line and B-CPAP (BRAF V600E/V600E) papillary thyroid carcinoma cell line were used to develop doxycycline-inducible anti-BRAF shRNA stable cell lines. The inhibitions of BRAF expression in these cells were confirmed with qPCR and Western blot. Impacts of BRAF protein inhibition on cellular functions and signalling pathways were observed through Western blot, proliferation and colony formation assays. BRAF kinase expression was inhibited 83 % in undifferentiated thyroid carcinoma and 82 % in papillary thyroid carcinoma (p < 0.05). As a result of BRAF kinase inhibition, reduction in MEK kinase activity was seen (p < 0.05) in both thyroid cancer cell lines (72 and 75 %, respectively). Initially, big drop in proliferation (p < 0.05) was observed (52 and 54 %, respectively), but later an increasing proliferation trend was noticed in BRAF kinase-inhibited cell lines. In addition, reduction in colony formation (p < 0.05) was seen in BRAF kinase-inhibited carcinoma cells (13 and 15 %, respectively). On the other hand, increase in AKT kinase activity (63 and 70 %, respectively; p < 0.05) was discovered in both BRAF kinase-inhibited carcinoma cells. Increased activation of alternative proliferation pathways (as determined by the increase of AKT kinase activity) counteracts the effect of BRAF kinase inhibition in thyroid carcinomas. Thus, alternative proliferation pathways should be inhibited for therapeutic suppression of BRAF-induced proliferation in thyroid carcinomas.
Mutation of FAM134B (Family with Sequence Similarity 134, Member B) leading to loss of function of its encoded Golgi protein and has been reported induce apoptosis in neurological disorders. FAM134B mutation is still unexplored in cancer. Herein, we studied the DNA copy number variation and novel mutation sites of FAM134B in a large cohort of freshly collected oesophageal squamous cell carcinoma (ESCC) tissue samples. In ESCC tissues, 37% (38/102) showed increased FAM134B DNA copies whereas 35% (36/102) showed loss of FAM134B copies relative to matched non-cancer tissues. Novel mutations were detected in exons 4, 5, 7, 9 as well as introns 2, 4-8 of FAM134B via HRM (High-Resolution Melt) and Sanger sequencing analysis. Overall, thirty-seven FAM134B mutations were noted in which most (31/37) mutations were homozygous. FAM134B mutations were detected in all the cases with metastatic ESCC in the lymph node tested and in 14% (8/57) of the primary ESCC. Genetic alteration of FAM134B is a frequent event in the progression of ESCCs. These findings imply that mutation might be the major driving source of FAM134B genetic modulation in ESCCs.
miR-205 plays a crucial role in angiogenesis and has been found in association with several types of cancers. The aims of this study were to investigate the clinical and functional roles of miR-205 on as the major initiator and modulator of angiogenesis in thyroid cancer. 101 thyroid carcinomas, including 51 conventional and 37 follicular variants of papillary thyroid carcinomas, and 13 undifferentiated thyroid carcinomas in addition to 13 lymph nodes with metastatic thyroid carcinoma were recruited to be compared with 14 nodular goitre and seven normal thyroid tissues. Five thyroid carcinoma cell lines, of papillary and undifferentiated origin with and without history of metastasis, were also used. Expression of vascular endothelial growth factor A (VEGFA) and miR-205 were measured and exogenous miR-205 were transfected to observe the changes of VEGFA (by immunofluorescence and western blot techniques). Proliferation assay, cell cycle analysis and apoptosis assays were also used to evaluate the role of miR-205 in these events. Significant under-expression of miR-205 and over-expression of VEGFA mRNA and protein were noticed in thyroid cancer tissues and cell lines compared to normal thyroid control. Transfection of miR-205 into the cancer cell lines caused significant reduction of VEGFA protein and significant inhibition in cell proliferation, arrest in G0-G1 of the cell cycle and promotion of total apoptosis (P<0.05). The angiogenic and tumour-suppressive roles of miRNA-205 were demonstrated for the first time in thyroid cancer. The current experiments provided specific information on the functional consequences of VEGF manipulation via miRNA on cancer.
In this study, we investigated the expression profiles and clinicopathological significance of miR-126 in large cohort of patients with colorectal cancers as well the cellular repercussions of miR-126 in colon cancer cells along with its targets in-vitro. Down regulation of miR-126 expression was associated with histological subtypes, peri-neural tumour infiltration, microsatellite instability and pathological staging of colorectal cancers (p<0.05). Low miR-126 expression was also associated with poorer survival in patients with colorectal cancer. Analysis of matched tissues from the same patient revealed that approximately 70% of the tested patients had similar levels of expression of miR-126 in primary cancer and cancer metastases in both lymph node and distant metastases. In addition, induced overexpression of miR-126 showed reduced cell proliferation, increased apoptosis and decreased accumulation of cells in the G0-G1 phase of the colon cancer cells. Furthermore, SW480(+miR-126) cells showed reduced BCL-2 and increased P53 protein expression. To conclude, deregulation of miR-126 in colorectal cancer at the tissue and cellular levels as well as its correlation with various clinicopathological parameters confirm the cancer suppressive role of miR-126 in colorectal cancer.
Background: The objectives of this study are to investigate the expression of miR-126 and evaluate its effect on proliferation in undifferentiated thyroid carcinoma. Methods: miR-126 expression of undifferentiated thyroid carcinoma cell lines 8505C (BRAF(V600/EN600E)), BHT-101 (BRAF(V600E/WT)) and MB-1 (BRAF(WT/WT)) were quantified with q-PCR. These cell lines were transiently transfected with exogenous miR-126 (mimic). Following transfection, proliferation effects were observed through MTS proliferation assay and colony formation abilities. Immunofluorescence imaging and Western blot assay were also done to check target proteins expression. Results: Under-expression (p < 0.05) of miR-126 was noted in BRAF(V600E) mutated undifferentiated thyroid carcinoma cells (8505C and BHT-101), but no change in expression was noted in non BRAF(V600E) mutated undifferentiated thyroid carcinoma cells (MB-1). In addition, a 30-50% drop in proliferation ability and a 35-45% reduction in colony formation capability were noticed in miR-126 mimic transfected group when compared to control group. Furthermore, immunofluorescence images showed reduced expression of p853 and p-AKT protein in miR-126 mimic transfected cells when compared to untransfected cells. Also, Western blot analysis revealed a 34-40% suppression of p85P protein and a 2153% drop in active AKT kinase (p-AKT) protein in miR-126 mimic transfected group when compared to control group. Conclusions: Expression of miR-126 was down-regulated in BRAF(V600E) mutated undifferentiated thyroid carcinoma. In addition, miR-126 was found to act as proliferation suppressor targeting PIK3R2 gene and reducing p85 beta (a regulatory subunit of PI3K kinase) protein translation and lower AKT kinase activity. Therefore, miR-126 could be a potential therapeutic tool in the treatment of undifferentiated thyroid carcinoma. (C) 2015 Elsevier Inc. All rights reserved.
BACKGROUND AND OBJECTIVES:BRAF is an oncogene which involves in pathogenesis of many thyroid carcinomas.The aim of our study was to investigate whether the downstream signalling pathway of BRAF and AKT kinase signalling pathways were active in BRAF V600E mutated thyroid carcinoma cells.METHODS:Five thyroid (papillary and undifferentiated) carcinoma cell lines and one non-cancer thyroid cell line were screened for their BRAF V600E mutation status by immunofluorescent staining and Western blot. BRAF V600E mutated thyroid carcinoma cell lines were used to test the activation status of both ERK and AKT kinase proteins through immunofluorescent studies and Western blots.RESULTS:Expressions of BRAF V600E mutated protein were confirmed in four thyroid (papillary and undifferentiated) carcinoma cell lines. In these cell lines, both active ERK and active AKT kinase proteins were found in BRAF V600E mutated thyroid carcinoma cells by immunofluorescent staining and Western blots experiments.CONCLUSIONS:In BRAF V600E mutated thyroid carcinomas, active ERK and active AKT kinase proteins were noted. They are able to stimulate multiple downstream signalling pathways which ultimately result in increased proliferation and survival activities for cancer cells. Therefore, consideration needs to put on multiple targets when deciding molecular target therapies for patients with BRAF V600E mutated thyroid carcinoma.
BRAF is a major oncoprotein and oncogenic mutations in BRAF are found in a significant number of cancers, including melanoma, thyroid cancer, colorectal cancer and others. Consequently, BRAF inhibitors have been developed as treatment options for cancers with BRAF mutations which have shown some success in improving patient outcomes in clinical trials. Development of resistance to BRAF kinase inhibitors is common, however, overcoming this resistance is an area of significant concern for clinicians, patients and researchers alike. In this review, we identify the mechanisms of BRAF kinase inhibitor resistance and discuss the implications for strategies to overcome this resistance in the context of new approaches such as multi-kinase targeted therapies and emerging RNA interference based technologies.
MicroRNA-34 is involved in pathogenesis in cancer by targeting different tumor-related genes. It could be a biomarker for predicting the prognosis of patients with cancer. In addition, miR-34 is involved in the tumor angiogenesis. Understanding the mechanism of the miR-34 in cancer and tumor angiogenesis will open horizons for development of anti-cancer and anti-angiogenesis drugs.
Altered expression of the microRNA-34 family has been determined to be involved in the pathogenesis of many cancers. In this review, the current knowledge of the cancer-related mechanisms in relation to the modulatory effects of microRNA-34 family were analysed. Expression analysis of the microRNA-34 family has suggested that its members play significant roles in many aspects of cancer biology including proliferation, invasion/metastasis, apoptosis/cell survival, cell cycle/cell growth, migration, senescence/aging, angiogenesis, epigenetic silencing and methylation by regulation of the expression of their target genes. Thus, microRNA-34 family members could act as prognostic markers and therapeutic targets in human cancers.