Showing papers in "Oncology Letters in 2013"
TL;DR: An integrated network collaboration of different sectors, including public health, agricultural departments and mass media, is required to ensure effective food regulation systems so as to minimize the contamination of food by aflatoxins.
Abstract: Hepatocellular carcinoma (HCC) is the most well-known primary liver malignancy worldwide. Its incidence is rising at alarming rates and has become a public concern globally. It is more frequent in developing countries than in industrialized countries with respect to geographical variation, ethnic disparities and socioeconomic status. Dietary exposure to aflatoxins is among the major HCC risk factors. Aflatoxin B1, which is a genotoxic hepatocarcinogen, which presumptively causes cancer by inducing DNA adducts leading to genetic changes in target liver cells. AFB1 is metabolized by cytochrome-P450 enzymes to the reactive intermediate AFB1-8, 9 epoxide (AFBO) which binds to liver cell DNA, resulting in DNA adducts. DNA adducts interact with the guanine bases of liver cell DNA and cause a mutational effect in the P53 tumor suppressor gene at the codon 249 hotspot in exon 7, which may lead to HCC. Approximately 4.5 billion of the world’s population is exposed to aflatoxin-contaminated food, particularly in low-income countries. Prevention involves treating crops that are susceptible to fungal contamination, appropriate handling of foodstuffs and the use of chemopreventive intervention. Moreover, an integrated network collaboration of different sectors, including public health, agricultural departments and mass media, is required to ensure effective food regulation systems so as to minimize the contamination of food by aflatoxins.
203 citations
TL;DR: Specific miRNA expression profiles exist in EC tissues and may serve as novel EC molecular markers and to identify new molecular markers for EC by analyzing the expression profiles of miRNAs inEC tissues.
Abstract: The aim of this study was to explore the association of specific microRNAs (miRNAs) with the development of esophageal cancer (EC) and to identify new molecular markers for EC by analyzing the expression profiles of miRNAs in EC tissues. The expression profiles of miRNAs in paired EC and paracancerous normal tissues were detected and bioinformatically analyzed using miRNA assays. The outcomes were validated using real-time polymerase chain reaction. The miRNA assays revealed a total of 60 differentially expressed miRNAs in the EC tissues compared with those in the paracancerous normal tissues. Among them, 51 had doubled or more than doubled their expression levels and 9 had halved their expression levels. The most markedly upregulated miRNAs were hsa-miR-15a, hsa-miR-28-3p, hsa-miR-31, hsa-miR-99b, hsa-miR-101, hsa-miR-130a, hsa-miR-143, hsa-miR-196b, hsa-miR-200a, hsa-miR-210, hsa-miR-452 and hsa-miR-27a, whereas the most markedly downregulated miRNAs included hsa-miR-30b, hsa-miR-223, hsa-miR-454, hsa-miR-486, hsa-miR-574-3p and hsa-miR-126. Specific miRNA expression profiles exist in EC tissues and may serve as novel EC molecular markers.
134 citations
TL;DR: This review discusses the correlation between CSCs, EMT and VM formation, and indicates that EMT is relevant to the acquisition and maintenance of stem cell-like characteristics.
Abstract: Vasculogenic mimicry (VM), a new pattern of tumor microcirculation, is important for the growth and progression of tumors. Epithelial-mesenchymal transition (EMT) is pivotal in malignant tumor progression and VM formation. With increasing knowledge of cancer stem cell (CSC) phenotypes and functions, increasing evidence suggests that CSCs are involved in VM formation. Recent studies have indicated that EMT is relevant to the acquisition and maintenance of stem cell-like characteristics. Thus, in this review we discuss the correlation between CSCs, EMT and VM formation.
112 citations
TL;DR: Treatment of HeLa and HTB-35 human cancer cells with gallic acid decreased cell viability in a dose-dependent manner and the suppression of ADAM17 and the downregulation of the EGFR, Akt/p-Akt and Erk/ p-Erk signaling pathways may contribute to the suppressed of cancer progression by Gallic acid.
Abstract: Gallic acid is a trihydroxybenzoic acid, also known as 3,4,5-trihydroxybenzoic acid, which is present in plants worldwide, including Chinese medicinal herbs. Gallic acid has been shown to have cytotoxic effects in certain cancer cells, without damaging normal cells. The objective of the present study was to determine whether gallic acid is able to inhibit human cervical cancer cell viability, proliferation and invasion and suppress cervical cancer cell-mediated angiogenesis. Treatment of HeLa and HTB-35 human cancer cells with gallic acid decreased cell viability in a dose-dependent manner. BrdU proliferation and tube formation assays indicated that gallic acid significantly decreased human cervical cancer cell proliferation and tube formation in human umbilical vein endothelial cells, respectively. Additionally, gallic acid decreased HeLa and HTB-35 cell invasion in vitro. Western blot analysis demonstrated that the expression of ADAM17, EGFR, p-Akt and p-Erk was suppressed by gallic acid in the HeLa and HTB-35 cell lines. These data indicate that the suppression of ADAM17 and the downregulation of the EGFR, Akt/p-Akt and Erk/p-Erk signaling pathways may contribute to the suppression of cancer progression by Gallic acid. Gallic acid may be a valuable candidate for the treatment of cervical cancer.
103 citations
TL;DR: Age is one of the major prognostic factors affecting survival in lung cancer patients; therefore, patients should be managed according to age in clinical practice.
Abstract: Despite all efforts at management, prognosis of advanced lung cancer is extremely poor, with a median survival time of ~1 year. The number of cancer patients aged >70 years is significantly increased among the cancer patient population. The aim of this study was to investigate the clinical importance of age in lung cancer. Data from 110 patients with histologically confirmed lung cancer, who were treated and followed up in the Institute of Oncology, University of Istanbul, were recorded from medical charts. There were 100 (91%) males with a median age of 59 years (range, 35–88 years). The majority of patients had non-small cell lung cancer (NSCLC; 84%) and metastatic stage (56%). The rate of positive response to chemotherapy was lower in elderly patients (P=0.01) and the incidence of anemia was higher compared with that in younger patients (P=0.02). The majority of mortalities occurred in elderly patients (P=0.01). The median survival time of elderly patients was significantly lower compared with that of younger patients (37.8 vs. 57 weeks; P=0.009). The 1-year survival rates in younger and elderly patients were 67.3 and 42.5%, respectively. In multivariate analysis, elderly patients also had significantly poorer survival (P=0.023). In the group of elderly patients, analyses revealed that significant prognostic factors, including stage of disease and serum lactate dehydrogenase (LDH) levels, were associated with survival. Elderly patients diagnosed with small cell lung cancer had a poorer outcome compared with those with NSCLC (P=0.009), and older patients with elevated serum LDH levels had a shorter survival time compared with those with normal levels (P=0.042). In conclusion, age is one of the major prognostic factors affecting survival in lung cancer patients; therefore, patients should be managed according to age in clinical practice.
102 citations
TL;DR: The number of PTEN mutations were low in the sporadic breast cancer cases analyzed in the present study and PTEN promoter methylation may have been the main mechanism leading to the decreased expression ofPTEN.
Abstract: The tumor suppressor gene, PTEN, has previously been demonstrated to be involved in breast tumorigenesis and tumor progression. The aim of the present study was to investigate the expression and significance of PTEN in breast carcinomas, to detect the mutation frequency of PTEN in sporadic breast carcinoma tissues and to determine the association between PTEN promoter methylation and gene expression. Immunohistochemical methods were used to analyze the expression of the PTEN gene in 146 cases of breast carcinoma and 10 cases of normal breast tissue closely adjacent to the carcinoma. Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis was used to analyze conformation polymorphisms in 45 breast carcinoma and 10 normal breast tissues. Point mutations of abnormal single stranded conformation were detected by DNA sequencing. The methylation of the PTEN promoter was analyzed by methylation-specific PCR. Expression of PTEN was detected in 57.5% (84/146) of patients with breast carcinoma. By contrast, PTEN expression was detected in 100% of normal samples. Expression of PTEN was found to negatively correlate with the tumor size, the pathological stage and the expression of the estrogen receptor (ER) and the progesterone receptor (PR) in breast cancer. The 2-year disease-free survival of patients with a high expression of PTEN was higher compared with those with low PTEN expression (P<0.05). Missense mutations in exon 2 of PTEN were identified in 1/45 breast cancer cases. PTEN promoter methylation was detected in 31.1% (14/45) of breast carcinomas, of which 64.3% (9/14) were associated with a loss of PTEN expression. The tumor suppressor gene, PTEN, was abnormally expressed in the breast carcinomas. The number of PTEN mutations were low (1/45) in the sporadic breast cancer cases analyzed in the present study and PTEN promoter methylation may have been the main mechanism leading to the decreased expression of PTEN. These results indicate that PTEN is important for the tumorigenesis, development and prognosis of breast cancer.
101 citations
TL;DR: The flow cytometry results indicated that apoptosis may be a major contributor to the biological efficacy of MCF-7 cells and the anticancer effects of myrrh were markedly increased compared with those of frankincense, however, no significant synergistic effects were identified.
Abstract: The present study aimed to investigate the composition and potential anticancer activities of essential oils obtained from two species, myrrh and frankincense, by hydrodistillation. Using gas chromatography-mass spectrometry (GC-MS), 76 and 99 components were identified in the myrrh and frankincense essential oils, respectively, with the most abundant components, 2-Cyclohexen-1-one, 4-ethynyl-4-hydroxy-3,5,5-trimethyl- and n-Octylacetate, accounting for 12.01 and 34.66%, respectively. The effects of the two essential oils, independently and as a mixture, on five tumor cell lines, MCF-7, HS-1, HepG2, HeLa and A549, were investigated using the MTT assay. The results indicated that the MCF-7 and HS-1 cell lines showed increased sensitivity to the myrrh and frankincense essential oils compared with the remaining cell lines. In addition, the anticancer effects of myrrh were markedly increased compared with those of frankincense, however, no significant synergistic effects were identified. The flow cytometry results indicated that apoptosis may be a major contributor to the biological efficacy of MCF-7 cells.
88 citations
TL;DR: This is the first study to investigate the endophytic microorganism isolated from O. japonicas and the first discovery of such antitumoral exopolysaccharides derived from the genus Bacillus, which provides a promising and reproducible natural product source with high therapeutic value for anticancer treatment, thereby facilitating the development of new anticancer agents.
Abstract: The endophytic bacterium, MD-b1, was isolated from the medicinal plant Ophiopogon japonicas and identified as the Bacillus amyloliquefaciens sp. with 99% similarity based on the partial sequence analysis of 16S rDNA. Exopolysaccharides were extracted from the endophyte for the evaluation of its antitumor activity against gastric carcinoma cell lines (MC-4 and SGC-7901). 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays and microscopy were performed to estimate the cell viability and morphological changes of the MC-4 and SGC-7901 cells following treatment with the exopolysaccharides at 14, 22 and 30 μg/μl. The results revealed that the exopolysaccharides displayed concentration-dependent inhibitory effects against the MC-4 and SGC-7901 cells, with an IC50 of 19.7 and 26.8 μg/μl, respectively. The exopolysaccharides also induced morphological abnormalities in the cells. These effects indicated the the exopolysaccharides had an antitumoral mechanism of action associated with the mitochondrial dysfunction of the treated cells. This is the first study to investigate the endophytic microorganism isolated from O. japonicas and also the first discovery of such antitumoral exopolysaccharides derived from the genus Bacillus. This provides a promising and reproducible natural product source with high therapeutic value for anticancer treatment, thereby facilitating the development of new anticancer agents.
86 citations
TL;DR: It is shown that ectopic expression of miR-26a inhibited the migratory and invasive capacities of NPC cells in vitro and in vivo and that its antimetastatic effects are mediated mainly by repressing EZH2 expression.
Abstract: Nasopharyngeal carcinoma (NPC) is a highly invasive and metastatic type of cancer that is widely prevalent in Southern China. Studies have shown that several microRNAs (miRNAs) are implicated in NPC metastasis. Our previous studies have demonstrated that miRNA miR-26a inhibits cell growth and tumorigenesis of NPC through the repression of enhancer of zeste homolog 2 (EZH2). However, the role of miR-26a in NPC metastasis remains unknown. In this study, we showed that ectopic expression of miR-26a inhibited the migratory and invasive capacities of NPC cells in vitro. Additionally, we used a murine model to investigate the role of miR-26a in NPC metastasis and results showed that miR-26a overexpression suppresses the metastatic behavior of NPC cells in vivo. Furthermore, the data demonstrated that miR-26a decreased the expression levels of EZH2 in vitro and in vivo, suggesting that the antimetastatic effect of miR-26a in NPC was mediated by regulating EZH2. Therefore, these findings indicate that miR-26a functions as an antimetastatic miRNA in NPC and that its antimetastatic effects are mediated mainly by repressing EZH2 expression.
78 citations
TL;DR: Results consistent with miR-182 as a novel and valuable biomarker for the diagnosis of BC are highlighted.
Abstract: MicroRNAs (miRNAs), present in the serum in a stable and reproducible manner, may be used as biomarkers for various diseases. Few studies have previously investigated circulating miRNAs in the peripheral blood of breast cancer (BC) patients. To identify the role of serum miR-182 levels in BC, the present study detected miR-182 levels in the serum of 46 BC patients and 58 controls, by quantitative PCR. The results showed that the serum miR-182 levels in BC patients were significantly higher compared with the serum of healthy controls (P<0.01). The miR-182 was also overexpressed in the BC tissues compared with the para-carcinoma tissues. Furthermore, the serum levels of miR-182 in the estrogen receptor (ER)-positive patients were considerably lower compared with those in the ER-negative patients. The serum levels of miR-182 in the progesterone receptor (PR)-positive patients were also found to be lower compared with those in the PR-negative patients. The current study highlights results consistent with miR-182 as a novel and valuable biomarker for the diagnosis of BC.
76 citations
TL;DR: The nervous system plays an important role in cancer metastasis through direct and indirect actions of the nervous system, which modulates angiogenesis, the tumor microenvironment, bone marrow, immune functions and inflammatory pathways to influence metastases.
Abstract: The notion that tumors lack innervation was proposed several years ago. However, nerve fibers are irregulatedly found in some tumor tissues. Their terminals interaction with cancer cells are considered to be neuro-neoplastic synapses. Moreover, neural-related factors, which are important players in the development and activity of the nervous system, have been found in cancer cells. Thus, they establish a direct connection between the nervous system and tumor cells. They modulate the process of metastasis, including degradation of base membranes, cancer cell invasion, migration, extravasation and colonization. Peripheral nerve invasion provides another pathway for the spread of cancer cells when blood and lymphatic metastases are absent, which is based on the interactions between the microenvironments of nerve fibers and tumor cells. The nervous system also modulates angiogenesis, the tumor microenvironment, bone marrow, immune functions and inflammatory pathways to influence metastases. Denervation of the tumor has been reported to enhance cancer metastasis. Stress, social isolation and other emotional factors may increase distant metastasis through releasing hormones from the brain, the hypothalamic-pituitary-adrenal axis and autonomic nervous system. Disruption of circadian rhythms will also promote cancer metastasis through direct and indirect actions of the nervous system. Therefore, the nervous system plays an important role in cancer metastasis.
TL;DR: It is demonstrated that the CA IX expression profiles in blood and tissue samples from 74 kidney cancer patients are closely correlated with their histological subtypes.
Abstract: Carbonic anhydrase IX (CA IX) is regarded as one of the most prominent markers of tumor hypoxia with potential to serve as a diagnostic biomarker, prognostic indicator as well as tumor therapeutic target. The aim of the present study was to perform an in-depth analysis of CA IX expression in blood and tissue samples and to evaluate the significance of CA IX status for different renal cell carcinomas (RCCs). The expression of CA IX was determined in blood and tissue samples from 74 kidney cancer patients using reverse transcription polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), Western blotting (WB) and immunohistochemistry (IHC). The CA IX status was correlated with RCC type and tumor stage. IHC and WB provided evidence for a significantly higher expression of CA IX in clear cell RCC (CCRCC) specimens compared to other RCCs. RT-PCR assay revealed that 32.42% of all RCC patients possess CA9-positive cells in peripheral blood and three-quarters of CA9-positive patients were diagnosed with CCRCC. When the patients were subdivided according to tumor stage, decreased positivity was observed with higher tumor stage (50% in T1 vs. 17% in T3). Serum CA IX levels determined by ELISA were significantly higher in CCRCC patients than in non-CCRCC. A significant association between s-CA IX and CCRCC tumor stage was also determined (T1-87.51 vs. T3-341.98 pg/ml, p=0.046). We demonstrated that the CA IX expression profiles in blood and tissue samples from 74 kidney cancer patients are closely correlated with their histological subtypes. This is the first study reporting CA IX expression in blood and tissue samples from kidney cancer patients determined by four different methods.
TL;DR: It is revealed that baicalein significantly inhibits growth and induces apoptosis in EC-109 human ESCC cells in vitro, thus providing further understanding of the molecular mechanisms of baicalsein action in esophageal carcinoma.
Abstract: Baicalein, a flavone present in Scutellaria baicalensis Georgi, has been demonstrated to possess antitumor activity in a variety of cancer cells in vitro. However, its effects on the growth inhibition and induction of apoptosis in human esophageal carcinoma cells remain unclear. The aims of this study were to determine whether cultured EC-109 esophageal squamous cell carcinoma (ESCC) cells undergo apoptosis when treated with baicalein and to investigate the underlying mechanisms in vitro. Cell growth was measured using MTT and plate colony formation assays. Induction of apoptosis was examined using Hoechst 33258 staining, flow cytometry analysis and a DNA fragmentation assay. The mechanisms underlying the observed growth suppression were examined using western blot analysis. The results demonstrated that treatment of EC-109 cells with baicalein for 48 h markedly decreased the rate of cell viability. Colony formation was almost fully suppressed at 40 μM baicalein. EC-109 cells underwent apoptosis in response to baicalein treatment, demonstrated by an increase in the percentage of cells stainable with Hoechst 33258 and Annexin V-FITC/PI, increased DNA fragmentation and activation of the intrinsic (mitochondrial) pathway for cell death. The latter was characterized by increased expression of the cleaved forms of caspase-9 and -3, and poly (ADP-ribose) polymerase (PARP). Additionally, baicalein was found to downregulate anti-apoptotic components and upregulate apoptotic components of the PI3K/Akt pathway. In conclusion, baicalein induces apoptosis in EC-109 cells through modulation of the PI3K/Akt pathway, thus providing further understanding of the molecular mechanisms of baicalein action in esophageal carcinoma. Therefore, the present study revealed that baicalein significantly inhibits growth and induces apoptosis in EC-109 human ESCC cells in vitro.
TL;DR: MRI evaluation is useful for predicting pCR following NAC, particularly for triple-negative tumors, and sensitivity and specificity were the highest (60 and 100%, respectively) in triple- negative tumors.
Abstract: In the present study, clinical tumor response following neoadjuvant chemotherapy (NAC) was diagnosed by magnetic resonance imaging (MRI) and clinicopathological factors, including molecular subtypes at baseline, were analyzed for correlations with pathological tumor responses. In addition, clinicopathological factors were analyzed for a correlation with the MRI capacity to predict pathological complete response (pCR). Clinical tumor response evaluated by MRI following NAC was determined as a clinical CR (cCR) or a residual tumor. cCR was confirmed if no gadolinium enhancement or an enhancement equal to or less than that of glandular tissue was observed in any phase of the MRI. Pathological tumor responses following NAC were classified into grades 0 (no change) to 3 (no residual invasive cancer) according to criteria of the Japanese Breast Cancer Society. pCR was defined as grade 3 in the present study. Of 264 cases of invasive breast cancer in 260 patients (4 synchronous bilateral breast cancer cases), 59 (22%) were diagnosed by MRI following NAC as cCR and 98 (37%) were pathologically diagnosed as pCR. In terms of predicting pCR by MRI, the sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) were 44, 90, 73, 73 and 73%, respectively. Tumor size, hormone receptor status, human epidermal growth factor receptor 2 (HER2) status, molecular subtype and histological type were significantly correlated with pathological tumor responses. pCR rates increased in the following order: luminal/HER2-negative (14%), luminal/HER2-positive (32%), triple-negative (46%) and non-luminal/HER2-positive (73%) tumors. Sensitivity and specificity were the highest (60 and 100%, respectively) in triple-negative tumors. PPV decreased in the following order: triple-negative (100%), non-luminal/HER2-positive (92%), luminal/HER2-positive (46%) and luminal/HER2-negative (33%) tumors. In conclusion, MRI evaluation is useful for predicting pCR following NAC, particularly for triple-negative tumors.
TL;DR: It is demonstrated that cisplatin and paclitaxel were able to induce autophagy and apoptosis in A549 lung cancer cells and the inhibition of autophagic inhibitor promoted cisplarin and pac litaxel-induced apoptosis.
Abstract: Chemotherapy is one of the main methods of cancer treatment and is known to induce autophagy in cancer cells. The main mechanism of chemotherapeutic agents is to promote apoptosis. In the process of chemotherapy, there is a unique association between autophagy and apoptosis. In this study, MDC staining, Hoechst 33342 staining and flow cytometry were used to explore the effects of autophagy on chemotherapy-induced apoptosis in A549 lung cancer cells and the association between autophagy and apoptosis was investigated via the addition of an autophagic inhibitor (3-methyladenine, 3-MA). This study demonstrated that cisplatin and paclitaxel were able to induce autophagy and apoptosis in A549 lung cancer cells and the inhibition of autophagy promoted cisplatin and paclitaxel-induced apoptosis. Furthermore, autophagy may play a protective role in the processes of cisplatin and paclitaxel-induced apoptosis.
TL;DR: The results showed that the relative expression levels of ZEB1 were significantly higher in CRC tissues compared to the normal adjacent mucosa and higher expression ofZEB1 correlated with liver metastasis, indicating the potential of Z EB1 as a novel prognostic biomarker for CRC.
Abstract: Zinc finger E-box binding homeobox 1 (ZEB1) has been shown to promote invasion and metastasis in several types of human cancer and to have a prognostic role in certain cancers. However, the clinical significance of ZEB1 in colorectal cancer (CRC) has not been sufficiently investigated. This study aimed to address this issue. In this study, we compared the expression of ZEB1 between CRC tissues and normal adjacent mucosa using quantitative real-time RT-PCR. The association of ZEB1 expression with clinicopathological characteristics was analyzed by appropriate statistical analyses. Kaplan-Meier analysis and Cox proportional hazards regression models were used to investigate the association of ZEB1 expression with survival of patients. The results showed that the relative expression levels of ZEB1 were significantly higher in CRC tissues compared to the normal adjacent mucosa and higher expression of ZEB1 correlated with liver metastasis. Kaplan-Meier analysis indicated that patients with high ZEB1 had a poor overall survival. Moreover, the multivariate analysis showed that high expression of ZEB1 was an independent predictor of overall survival. Our data indicate the potential of ZEB1 as a novel prognostic biomarker for CRC.
TL;DR: The four-miRNA signature identified by genome-wide serum miRNA expression profiling analysis provides a novel, non-invasive approach for EEC diagnosis.
Abstract: Serum microRNAs (miRNAs), with their remarkable stability and unique concentration profiles in patients with various diseases, are promising non-invasive biomarkers for tumor detection. The present study investigated the altered profiles of serum microRNAs in patients with endometrioid endometrial cancer (EEC) in order to predict the malignancy of the disease at a relatively early stage. TaqMan® low-density arrays (TDLAs) were used to perform an analysis in the initial screening phase using serum samples pooled from seven EEC patients and 20 controls. The differential expression was validated using a hydrolysis probe-based stem-loop quantitative reverse transcription polymerase chain reaction (qRT-PCR) in samples taken from 26 EEC patients and 22 age- and gender-matched healthy controls. The data obtained from the TLDAs demonstrated that 22 serum miRNAs were markedly upregulated in the EEC patients compared with the controls. The qRT-PCR analysis further identified a profile of four serum miRNAs (miR-222, miR-223, miR-186 and miR-204) as a fingerprint for EEC detection. The area under the receiver operating characteristic (ROC) curve of this four-serum miRNA signature was 0.927, which was markedly higher than that of carbohydrate antigen 125 (CA-125; 0.673). The four-miRNA signature identified by genome-wide serum miRNA expression profiling analysis provides a novel, non-invasive approach for EEC diagnosis.
TL;DR: Differential tumor suppressor roles for miR-34c-3p and miC-34C-5p are suggested and new insights are provided into the role of miR -34c in glioma, which includes tumor-suppressing effects on proliferation, apoptosis and invasiveness.
Abstract: Glioblastoma is the most malignant and common intrinsic brain tumor, but the molecular mechanism of glioma pathophysiology is poorly understood. Recent data have shown that microRNAs regulate the expression of several genes associated with human cancer. In the present study, the function of miR-34c in glioma cells was analyzed. It was demonstrated that miR-34c-3p and miR-34c-5p were downregulated in gliomas, by performing qPCR on tumor tissues from glioma patients and glioma cell lines, compared with normal brain tissues and a normal glial cell line. Furthermore, the miR-34c expression was found to be inversely correlated with glioma WHO grades. Overexpression of miR-34c-3p inhibited U251 and U87 cell proliferation; however, miR-34c-5p only had an effect on U251 cells. Transfection with miR-34c-3p or miR-34c-5p in U251 cells and with miR-34c-3p in U87 cells produced S-phase arrest with G0/G1 reduction and induced cell apoptosis, but no significant changes were observed with miR-34c-5p transfection in U87 cells, normal or negative control groups. However, significant inhibition of glioma cell invasion was observed following transfection with miR-34c-3p and miR-34c-5p. Moreover, it was identified that miR-34c-3p overexpression reduced the expression of Notch pathway members, but miR-34c-5p overexpression did not. Therefore, these results suggest differential tumor suppressor roles for miR-34c-3p and miR-34c-5p and provide new insights into the role of miR-34c in glioma, which includes tumor-suppressing effects on proliferation, apoptosis and invasiveness.
TL;DR: Annexin A1, A2, A4 and A5 played important roles in breast cancer, pancreatic cancer and laryngeal carcinoma, alone and/or synergistically, and they may be targets of therapy for malignant tumors.
Abstract: Annexins are associated with metastasis and infiltration of cancer cells. Proteomic analysis and immunohistochemical staining were used to understand whether several annexins play important roles in cancer alone and/or synergistically. Seven fresh breast cancer samples with 23 paraffin specimens, three fresh pancreatic samples and five fresh laryngeal carcinoma samples with 25 paraffin specimens were obtained from humans, as well as ten golden hamster pancreatic cancer tissue samples, and they were used to observe differential expression of annexins compared with normal tissues using proteomics and immunohistochemical staining. Annexin A2, A4 and A5 were overexpressed in human breast cancer and laryngeal carcinoma tissues and in golden hamster pancreatic cancer tissue samples, respectively, as shown by proteomics and immunohistochemical staining. In addition, annexin A4 and A5 were expressed in breast cancer tissues, while annexin A1 was not expressed. Annexin A1, A2 and A4 were expressed in human laryngeal carcinoma tissues as shown by immunohistochemical staining. Annexin A1, A2, A4 and A5 played important roles in breast cancer, pancreatic cancer and laryngeal carcinoma, alone and/or synergistically, and they may be targets of therapy for malignant tumors. The choice of which annexins to target should depend on their respective biological behaviors.
TL;DR: It is suggested that hypoxia induces EMT in oral squamous cell carcinoma cell lines via activation of Notch signaling, and inhibition of the Notch pathway to suppress EMT may be a useful approach for the treatment of OSCC.
Abstract: Epithelial-mesenchymal transition (EMT) is an early step in the acquisition of invasiveness by malignant tumors. It has been clarified that the tumor microenvironment affects malignancy in a number of different carcinomas, in particular, that a hypoxic environment induces EMT. Activation of Notch signaling induces EMT, but it remains unclear how the Notch pathway is involved in oral squamous cell carcinoma (OSCC) under hypoxia. Three OSCC cell lines were cultured for examination under hypoxic (1% O2) and normoxic (21% O2) conditions. Expression of E-cadherin was investigated as a hallmark of EMT by immunohistochemical examination. Cell motility and invasion were examined by wound-healing and invasion assays, respectively. The expression of Notch pathway molecules was analyzed by qPCR. Hypoxia increased the mRNA expression of Notch receptors, ligands and target genes, and Snail. Hypoxia decreased the expression of E-cadherin, and increased the motility and invasiveness of OSCC cell lines. γ-secretase inhibitor, a Notch-specific inhibitor, prevented these effects caused by h-ypoxia. These findings suggest that hypoxia induces EMT in OSCC cell lines via activation of Notch signaling, and inhibition of the Notch signaling pathway to suppress EMT may be a useful approach for the treatment of OSCC.
TL;DR: The present preliminary study identified the methylation profiles of normal and cancerous colonic epithelial tissues, and provided the groundwork for future large-scale methylation studies.
Abstract: Sporadic colorectal cancer (CRC) is a consequence of the accumulation of genetic and epigenetic alterations that result in the transformation of normal colonic epithelial cells to adenocarcinomas. Studies have indicated that a common event in the tumorigenesis of CRC is the association of global hypomethylation with discrete hypermethylation at the promoter regions of specific genes that are involved in cell cycle regulation, DNA repair, apoptosis, angiogenesis, adhesion and invasion. The present study aimed to investigate the epigenetic changes (DNA methylation) in 24 candidate genes in CRC. A total of 10 candidate hypermethylated (HM) and unmethylated (UM) genes were identified that may be useful epigenetic markers for non-invasive CRC screening. The five genes that had the highest average UM percentages in the control group were MLH1 (71.7%), DKK2 (69.6%), CDKN2A (68.4%), APC (67.5%) and hsa-mir-342 (67.4%). RUNX3 (58.9%), PCDH10 (55.5%), SFRP5 (52.1%), IGF2 (50.4%) and Hnf1b (50.0%) were the five genes with the highest average HM percentages in the test group. In summary, the present preliminary study identified the methylation profiles of normal and cancerous colonic epithelial tissues, and provided the groundwork for future large-scale methylation studies.
TL;DR: The major complication of BMs are SREs which are responsible for reducing prognoses and patient quality of life and are correlated with high rates of hospitalisation with the subsequent social and economic consequences.
Abstract: Breast cancer (BC) is the most common tumour in females and as a result, the management of such patients is a major public health issue. A high percentage of BC patients develop bone metastases (BMs), occasionally even several years following the initial diagnosis. BMs are responsible for high morbidity and a reduced quality of life with the onset of various clinical complications defined as skeletal-related events (SREs), including pathological fractures, spinal cord compression, hypercalcaemia, bone marrow infiltration and severe bone pain, requiring palliative radiotherapy. Such complications reduce functional independence and quality of life, decrease survival rates and increase healthcare costs. The current treatment for metastatic BC aims to achieve meaningful clinical responses, an improved quality of life, long-term remission, prolonged survival and in a small percentage of cases, a complete cure. The treatment of this malignancy has become progressively complex, including well-known antitumour agents or bone-targeted molecules aimed at preventing bone complications and improving patient quality of life and the treatment outcome of a multidisciplinary programme. The importance of a multi disciplinary approach in the management of BMs is also widely accepted. The major complication of BMs are SREs which are responsible for reducing prognoses and patient quality of life and are correlated with high rates of hospitalisation with the subsequent social and economic consequences. For these reasons, it is crucial to prevent where possible or to identify and treat SREs promptly in an attempt to mitigate the ever-increasing clinical and economic burden.
TL;DR: Human males absent on the first (hMOF) and its regulated gene, HCP5, are frequently downregulated in human ovarian cancer, suggesting that hMOF may be involved in the pathogenesis of the disease.
Abstract: Human males absent on the first (hMOF), a human ortholog of the Drosophila MOF protein, is responsible for histone H4 lysine 16 (H4K16) acetylation in human cells. The depletion of hMOF leads to a global reduction in histone H4K16 acetylation in human cells, genomic instability, cell cycle defects, reduced transcription of certain genes, defective DNA damage repair and early embryonic lethality. Studies have shown that abnormal hMOF gene expression is involved in a number of primary cancers. The present study examined the involvement of hMOF expression and histone H4K16 acetylation in clinically diagnosed primary ovarian cancer tissues. Clinically diagnosed frozen primary ovarian cancer tissues were used for polymerase chain reaction (PCR), quantitative PCR (qPCR), western blotting and immunohistochemical staining approaches. A PCR analysis of mRNA expression in 47 samples revealed a downregulation of hMOF mRNA in 81% of patients, whereas only 13% of patients demonstrated upregulation. qPCR was used to validate the frequent downregulation of hMOF expression in the primary ovarian cancer tissues. As expected, the analysis of hMOF expression in 57 samples revealed that hMOF mRNA expression was significantly downregulated (>2-fold decrease) in 65% of patients, while a 87% of patients with a decrease in hMOF. hMOF and its regulated gene, HCP5, are frequently downregulated in human ovarian cancer, suggesting that hMOF may be involved in the pathogenesis of the disease.
TL;DR: It is shown that miR-223 functions as a tumor suppressor, which may fine-tune the activity of the IGF-1R pathway in lung cancer, and increasing miR -223 expression may provide a novel approach for the treatment of NSCLC.
Abstract: microRNAs (miRNAs) have been hypothesized to function as oncogenes or tumor suppressors by targeting specific cancer-related genes. Previous studies have reported that miR-223 may serve as a tumor suppressor in a number of cancer types, however, knowledge of its targets in non-small cell lung cancer (NSCLC) remains limited. In the current study, miR-223 was found to inhibit cell proliferation in vitro by CCK-8 assay, growth curves and an anchorage-independent growth assay in a Lewis lung carcinoma (LLC) cell line. miR-223 transfection in the LLC cells was observed to significantly inhibit migration and invasion, induce G2/M arrest and decrease the expression levels of Sca-1, a marker of murine stem cells. In addition, miR-223 transfection markedly suppressed AKT and ERK signaling, as well as insulin-like growth factor-1 receptor (IGF-1R)-mediated downstream signaling, pathways that are crucial for cell proliferation and invasion in NSCLC cells. Analyses in C57BL/6 mice demonstrated that miR-223 suppresses tumorigenicity in vivo. Using a luciferase activity assay and western blot analysis, IGF-1R and cyclin-dependent kinase 2 (CDK2) were identified as direct targets of miR-223. In the present study, novel cancer-related targets of miR-223 were identified and verified in a LLC cell line, indicating that miR-223 functions as a tumor suppressor, which may fine-tune the activity of the IGF-1R pathway in lung cancer. Therefore, increasing miR-223 expression may provide a novel approach for the treatment of NSCLC.
TL;DR: It is suggested that EMT expression profiles are useful prognostic markers for disease-free survival in HCC patients, and that the E-cadherin(low)/vimentin(high) expression profile is closely associated with high-grade malignant behavior such as tumoral vascular invasion and metastasis in H CC.
Abstract: Epithelial-mesenchymal transition (EMT) plays a pivotal role in cancer invasion and metastasis, and transforming growth factor (TGF)-β signaling is a potent inducer of EMT. However, the clinical significance of the correlation between EMT marker expression and TGF-β signaling in hepatocellular carcinoma (HCC) patients remains unknown. In this study, immunohistochemistry was used to analyze the expression of EMT markers and phospho-Smad2 nuclear positivity, and their association with clinicopathological features in 150 HCC patients. E-cadherinhigh/vimentinlow and E-cadherinlow/vimentinhigh expression profiles were determined in 55 (36.7%) and 21 (14.0%) patients, respectively. The E-cadherinlow/vimentinhigh expression profile was significantly correlated with poor tumor differentiation (P<0.001), vascular invasion (P=0.007) and extrahepatic recurrence following curative surgery (P=0.026). Furthermore, the E-cadherinlow/vimentinhigh expression profile was significantly correlated with shorter disease-free survival compared to E-cadherinhigh/vimentinlow (P=0.002). Forty-one patients (27.3%) were demonstrated to have high phospho-Smad2 nuclear positivity, which was significantly correlated with the E-cadherinlow/vimentinhigh expression profile (P<0.001). In conclusion, this study suggests that EMT expression profiles are useful prognostic markers for disease-free survival in HCC patients, and that the E-cadherinlow/vimentinhigh expression profile is closely associated with high-grade malignant behavior such as tumoral vascular invasion and metastasis in HCC. Additionally, TGF-β-mediated EMT may play an important role in the aggressiveness of HCC.
TL;DR: Results showed that the overexpression of periostin predicts a poor prognosis, therefore it may be regarded as a novel molecule in the progression and development of NSCLC.
Abstract: The periostin protein, encoded by the POSTN gene, is a component of the extracellular matrix, which is expressed by fibroblasts and has been observed in a variety of human malignancies. The present study aimed to detect the expression of periostin in the tissues of non-small cell lung cancer (NSCLC) patients and benign lung tumors, and to correlate the results with the clinicopathological data of the subjects, in order to evaluate periostin as a potential prognostic marker. In total, 49 NSCLC patients and 6 benign lung tumors were included in this study. The protein level of periostin was detected in paired normal/paratumor/cancer tissues by a western blot analysis and the mRNA level in paired normal/cancer tissues was detected by quantitative polymerase chain reaction (qPCR). The results were then correlated with established biological and prognostic factors. Immunohistochemistry was used to confirm the location of periostin in the NSCLC tissues. Uni- and multivariate analyses were performed using Cox’s proportional hazards regression model. The protein level of periostin was elevated in the cancer tissue of the NSCLC patients compared with the normal (P=0.017) and paratumor (P=0.000) tissues. The expression level in the male patients was much higher than in the female patients at the protein (P=0.001) and mRNA (P=0.010) levels. The mRNA level in the non-adenocarcinoma (non-ADC) patients was much higher than in the adenocarcinoma (ADC) patients (P=0.029). Periostin was demonstrated higher expression at the protein level in the pseudotumors and tuberculosis patients than in the adjacent (P=0.016) and surrounding tissues (P=0.001). Immunostaining indicated that high levels of periostin were present in the mesenchymal areas, but not in the cancer cells themselves. The patients with tumors exhibiting high-level periostin expression showed a significantly shorter survival time (P=0.036, log-rank test). The 3-year survival rate was 81.5% for patients with low-level periostin expression (periostin-L; n=27) and 45.4% for patients with high-level periostin expression (periostin-H; n=22). Similarly, pathological node (pN) status was a significant prognostic marker in the univariate Cox survival analysis. Notably, periostin-H expression was also identified as an independent prognostic factor by the multivariate analysis (P=0.011). These results showed that the overexpression of periostin predicts a poor prognosis, therefore it may be regarded as a novel molecule in the progression and development of NSCLC. The results provide an additional target for the adjuvant treatment of NSCLC.
TL;DR: Matrine was shown to significantly inhibit the proliferation of HT29 cells in a dose- and time-dependent manner, and also to reduce the percentage of cells in the G2/M phase, which was most frequently associated with an increase of cells arrested in theG0/G1 phase of the cell cycle.
Abstract: Matrine is one of the main active components that is extracted from the dry roots of Sophora flavescens. The compound has potent antitumor activity in various cancer cell lines. However, the anticancer activity of matrine in colon cancer cells remains unclear. The purpose of the present study was to investigate the effects of matrine on the growth of human colon cancer cells and the expression of the associated proteins. Cancer cell proliferation was measured by 3-(4,5-dimethylthiazolyl)-2,5-diphenyl-tetrazolium bromide (MTT) assay. The cell cycle distribution and apoptosis were analyzed by flow cytometry (FCM). The activation of the caspases and the expression of pro-apoptotic and anti-apoptotic factors were examined using western blot analysis. Matrine was shown to significantly inhibit the proliferation of HT29 cells in a dose- and time-dependent manner, and also to reduce the percentage of cells in the G2/M phase, which was most frequently associated with an increase of cells arrested in the G0/G1 phase of the cell cycle. Western blot analysis revealed that matrine induced the activation of caspase-3 and -9 and the release of cytochrome C (Cyto C) from the mitochondria to the cytosol. Furthermore, the pro-apoptotic factor, Bax, was upregulated and the anti-apoptotic factor, Bcl-2, was downregulated, eventually leading to a reduction in the ratio of Bcl-2/Bax proteins. The results demonstrated that matrine inhibits proliferation and induces apoptosis of HT29 human cells in vitro. The induction of apoptosis appears to occur through the upregulation of Bax, the downregulation of Bcl-2, the release of Cyto C from the mitochondria to the cytosol and the activation of caspase-3 and caspase-9, which subsequently trigger major apoptotic cascades. Matrine has potent antitumor activity in HT29 cells and may be used as a novel effective reagent in the treatment of colon cancer.
TL;DR: Platinum-based chemotherapy in the breast cancer patients with TNBC showed an improved short-term efficacy compared with the non-TNBC group during neo-adjuvant chemotherapy, but has not yet been demonstrated to have an improved effect in advanced breast cancer.
Abstract: Triple-negative breast cancer (TNBC) tumors do not express estrogen, progesterone or HER2/neu-receptors. There are no specific treatment guidelines for TNBC patients, however, it has been postulated that their phenotypic and molecular similarity to BRCA1-associated cancers would confer sensitivity to certain cytotoxic agents, including platinum. The aim of this meta-analysis was to evaluate the clinical outcome of breast cancer patients treated with platinum-based chemotherapy who had TNBC compared with those with non-TNBC. Electronic (MEDLINE, EMBASE and Cochrane Library databases) and manual searches were conducted throughout December 2011 to identify trials evaluating the use of platinum-based chemotherapy for patients with breast cancer. The methodological quality was assessed in accordance with the QUOROM statement. Seven studies met the eligibility criteria, with a total of 717 patients. Of these patients, 225 were TNBC patients (31%), 492 were non-TNBC patients (69%), 275 received platinum-based neo-adjuvant chemotherapy and 442 had advanced/metastatic breast cancers. The results showed that during neo-adjuvant chemotherapy, the clinical complete response (cCR) rate and the pathological complete response (pCR) rates were significantly higher for the TNBC group compared with the non-TNBC group (OR, 2.68; 95% CI, 1.69-6.57; P=0.03 and OR, 2.89; 95% CI, 1.28, 6.53; P= 0.01, respectively). However, in advanced/metastatic breast cancers, the cCR, partial response (PR) and the disease control rates for the TNBC group were not significantly different compared with the non-TNBC group. The 6-month progression-free survival (PFS) rate for the TNBC group was higher than that of the non-TNBC group in all patients (OR, 1.81; 95% CI, 1.11-2.96; P= 0.02). However, the 1- and 2-year PFS rates were not significantly different (OR, 1.42; 95% CI, 0.69-2.92; P=0.35 and OR, 1.11; 95% CI, 0.35-3.52; P= 0.85, respectively). Furthermore, the PFS rates were not significantly different between the groups in patients with advanced/metastatic breast cancer. In conclusion, platinum-based chemotherapy in the breast cancer patients with TNBC showed an improved short-term efficacy compared with the non-TNBC group during neo-adjuvant chemotherapy, but has not yet been demonstrated to have an improved effect in advanced breast cancer.
TL;DR: In this paper, the role of miR-21 in the development of drug resistance in ovarian cancer cells was investigated by using real-time PCR and western blot analysis, and miR21 was found to be involved in drug resistance and the regulation of MDR1/P-gp expression, at least in part, by targeting HIF-1α.
Abstract: Drug resistance is a major problem encountered in the treatment of ovarian cancer. Previous studies have demonstrated that in several types of cancer the overexpression of the multidrug resistance 1 (MDR1) gene is mainly associated with drug resistance. The present study aimed to investigate the role of miR-21 in the development of drug resistance in ovarian cancer cells. The expression levels of miR-21 in the ovarian cancer A2780 and A2780/taxol cell lines were detected by stem-loop real-time PCR. A2780 and A2780/taxol cells were transfected with mimics or inhibitors of miR-21 or negative control RNA. The expression levels of P-glycoprotein (P-gp) and hypoxia-inducible factor-1α (HIF-1α) proteins were assessed by western blot analysis. Drug sensitivity was analyzed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The expression levels of miR-21 and P-gp were upregulated to a greater extent in the paclitaxel-resistant ovarian cancer A2780/taxol cell line compared with the parental A2780 cell line. Transfection of A2780/taxol cells with inhibitors of miR-21 decreased the expression levels of the P-gp and HIF-1α proteins, and increased the sensitivity of the A2780/taxol cells to paclitaxel. The expression levels of P-gp were additionally increased; however, the sensitivity of the miR-21 mimic-treated A2780 cells to paclitaxel was decreased. miR-21 may be involved in the development of drug resistance and the regulation of MDR1/P-gp expression, at least in part, by targeting HIF-1α in ovarian cancer cells.
TL;DR: The purpose of the present review is to provide a comprehensive review of PXR and its potential roles in multidrug resistance and the biological characteristics of PxR-positive tumors.
Abstract: Pregnane X receptor (PXR) is a member of the nuclear receptor superfamily of ligand-regulated transcription factors. PXR is a key xenobiotic receptor that regulates the expression of genes implicated in drug metabolism, detoxification and clearance, including drug metabolizing enzymes and transporters, suggesting that it is significant in the drug resistance of cancer cells. PXR is expressed in a wide range of tissues in the human body. Studies have demonstrated that PXR is expressed in a variety of tumor types, correlating not only with drug resistance but also with the cell proliferation, apoptosis and prognosis of cancer. The purpose of the present review is to provide a comprehensive review of PXR and its potential roles in multidrug resistance and the biological characteristics of PXR-positive tumors.