PLAT

Gene Summary

Gene:PLAT; plasminogen activator, tissue type
Aliases: TPA, T-PA
Location:8p11.21
Summary:This gene encodes tissue-type plasminogen activator, a secreted serine protease that converts the proenzyme plasminogen to plasmin, a fibrinolytic enzyme. The encoded preproprotein is proteolytically processed by plasmin or trypsin to generate heavy and light chains. These chains associate via disulfide linkages to form the heterodimeric enzyme. This enzyme plays a role in cell migration and tissue remodeling. Increased enzymatic activity causes hyperfibrinolysis, which manifests as excessive bleeding, while decreased activity leads to hypofibrinolysis, which can result in thrombosis or embolism. Alternative splicing of this gene results in multiple transcript variants, at least one of which encodes an isoform that is proteolytically processed. [provided by RefSeq, Jan 2016]
Databases:VEGA, OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:tissue-type plasminogen activator
Source:NCBIAccessed: 15 March, 2017

Ontology:

What does this gene/protein do?
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Pathways:What pathways are this gene/protein implicaed in?
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Cancer Overview

Research Indicators

Publications Per Year (1992-2017)
Graph generated 15 March 2017 using data from PubMed using criteria.

Literature Analysis

Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic.

  • Mutation
  • Cancer Gene Expression Regulation
  • Biomarkers, Tumor
  • Genome-Wide Association Study
  • Polymerase Chain Reaction
  • Staging
  • Receptors, Fibroblast Growth Factor
  • RT-PCR
  • Restriction Mapping
  • Withanolides
  • Oligonucleotide Array Sequence Analysis
  • Lung Cancer
  • Bladder Cancer
  • Newborns
  • Transcriptional Regulator ERG
  • Tumor Suppressor Proteins
  • Translocation
  • Prostate Cancer
  • p53 Protein
  • Base Sequence
  • Chromosome 8
  • Retinoic Acid
  • MicroRNAs
  • France
  • Precursor B-Cell Lymphoblastic Leukemia-Lymphoma
  • Gene Expression Profiling
  • Infant
  • Childhood Cancer
  • Gene Amplification
  • Chromosome Deletion
  • Adolescents
  • Pancreatic Cancer
  • Tissue Plasminogen Activator
  • Messenger RNA
  • Restriction Fragment Length Polymorphism
  • Vincristine
  • Cancer DNA
  • RTPCR
  • Gene Deletion
  • Reproducibility of Results
  • Breast Cancer
Tag cloud generated 15 March, 2017 using data from PubMed, MeSH and CancerIndex

Specific Cancers (5)

Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.

Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).

Latest Publications: PLAT (cancer-related)

Leekha A, Gurjar BS, Tyagi A, et al.
Vitamin C in synergism with cisplatin induces cell death in cervical cancer cells through altered redox cycling and p53 upregulation.
J Cancer Res Clin Oncol. 2016; 142(12):2503-2514 [PubMed] Related Publications
PURPOSE: Cervical cancer is the second most prevalent cancer in women worldwide. Survival of patients has been improved by cisplatin-based chemotherapy, but its effectiveness is limited due to its adverse effects on many tissues, especially nephrotoxicity. To optimize the efficacy of CDDP, we propose a combination therapy using natural products with minimal side effects. Vitamin C being a natural antioxidant is capable of selectively targeting cancer cells at pharmacological concentrations. Vitamin C synergistically enhances the activity of chemotherapeutic agents without increasing toxicity to normal cells. Therefore, we exploited co-therapy with cisplatin and vitamin C to kill cervical cancer cells.
METHODS: We elucidated the role of CDDP and VC on cervical cancer cell line (SiHa) by using cell growth assays, DNA fragmentation analysis, comet assay, in vitro morphological assessment of apoptosis (AO/EB and DAPI staining), ROS analysis by DCFDA, flow cytometry, biochemical assays (GST, GSH, NO, catalase, TPA) and Western blotting.
RESULTS: Our results clearly demonstrated that CDDP and VC treatment exhibited ameliorative effect on induction of cell death by p53 overexpression and generation of hydrogen peroxide in SiHa cells, thereby reducing the dosage of CDDP required to induce cell death in cancer cells.
CONCLUSIONS: These studies provide novel approaches to combat cisplatin resistance in cervical cancer.

Li J, Liu C, Sato T
Novel Antitumor Invasive Actions of p-Cymene by Decreasing MMP-9/TIMP-1 Expression Ratio in Human Fibrosarcoma HT-1080 Cells.
Biol Pharm Bull. 2016; 39(8):1247-53 [PubMed] Related Publications
p-Cymene (4-isopropyltoluene) has been reported to have beneficial actions such as anti-inflammatory and antinociceptive activities. To evaluate whether p-cymene exhibits antitumor invasive actions, we examined the effects of p-cymene on the production of matrix metalloproteinase 9 (MMP-9)/gelatinase B and tissue inhibitor of metalloproteinases-1 (TIMP-1) in human fibrosarcoma HT-1080 cells. p-Cymene was found to dose-dependently inhibit the 12-O-tetradecanoylphorbol 13-acetate (TPA)-augmented production and gene expression of MMP-9 in HT-1080 cells. In contrast, p-cymene enhanced the TPA-augmented production and gene expression of TIMP-1 in HT-1080 cells. However, there was no change in the constitutive level of MMP-9 and TIMP-1 mRNAs and TIMP-1 protein in p-cymene-treated cells. In addition, we found that the in-vitro TPA-augmented invasiveness of HT-1080 cells was inhibited by p-cymene in a dose-dependent manner. Furthermore, p-cymene was found to suppress the constitutive and/or TPA-augmented phosphorylation of extracellular signal-regulated kinase (ERK)1/2 and p38 mitogen-activated protein kinase (MAPK) in HT-1080 cells. Thus, these results provide novel evidence that p-cymene is an effective candidate for the prevention of tumor invasion and metastasis through mechanisms that include the inhibition of MMP-9 expression and the augmentation of TIMP-1 production along with the suppression of ERK1/2 and p38 MAPK signal pathways in tumor cells.

Kristiansen S, Nielsen D, Sölétormos G
Detection and monitoring of hypermethylated RASSF1A in serum from patients with metastatic breast cancer.
Clin Epigenetics. 2016; 8:35 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Circulating hypermethylated RASSF1A could be a novel and potential useful marker for monitoring patients with metastatic breast cancer. Technical obstacles include fragmentation of the circulating DNA, fluctuations in the concentration, low concentrations of circulating tumor DNA, and different locations of methylation in the RASSF1A gene among patients. One common method for detection of hypermethylated genes is sodium bisulfite conversion of non-methylated cytosine to uracil, followed by detection with PCR. However, the method relies on full conversion of all non-methylated cytosines, cause strand breaks, and loss of DNA. Alternatively, methylation-sensitive restriction enzymes have been used to digest genomic DNA, as well as sodium bisulfite-treated DNA. By flanking different regions of the RASSF1A with different PCR primer pairs, we analyzed for methylated genomic regions resistant to cleavage by the methylation-sensitive restriction enzymes HpaII and BstUI. The goal was to find region(s) in RASSF1A with high sensitivity and specificity that could be used for monitoring.
RESULTS: The serum was spiked with non-human control DNA. By tracing the spiking control, the isolation procedure of the rare circulating tumor DNA was initially optimized. By analysis of production of PCR amplicons from HpaII- or BstUI-treated DNA isolated from 24 patients with metastatic breast cancer, we located four regions resulting in sensitivities from 63 to 83 %. When examining samples from 24 control subjects, these four regions gave a specificity of 100 %. Among these four regions, the primer pair with the highest PCR efficacy was selected to monitor the RASSF1A concentration in 31 collected serum samples. The spiked DNA was then used to calculate the tumor RASSF1A concentrations independent of fluctuations in circulating non-tumor DNA. As a proof of principle, there was concordance in the kinetics of the RASSF1A and the serological cancer biomarkers CA 15-3, CEA, and TPA.
CONCLUSIONS: Methylation-sensitive restriction enzymes may be a useful methodological approach for monitoring circulating hypermethylated RASSF1A among patients with metastatic breast cancer.

Hong B, Su Z, Zhang C, et al.
Reserpine Inhibit the JB6 P+ Cell Transformation Through Epigenetic Reactivation of Nrf2-Mediated Anti-oxidative Stress Pathway.
AAPS J. 2016; 18(3):659-69 [PubMed] Article available free on PMC after 17/03/2017 Related Publications
UNLABELLED: Nuclear factor erythroid-2 related factor 2 (Nrf2) is a crucial transcription factor that regulates the expression of defensive antioxidants and detoxification enzymes in cells. In a previous study, we showed that expression of the Nrf2 gene is regulated by an epigenetic modification. Rauvolfia verticillata, a traditional Chinese herbal medicine widely used in China, possesses anticancer and antioxidant effects. In this study, we investigated how Nrf2 is epigenetically regulated by reserpine, the main active component in R. verticillata, in mouse skin epidermal JB6 P+ cells. Reserpine induced ARE (antioxidant response element)-luciferase activity in HepG2-C8 cells. Accordingly, in JB6 P+ cells, it upregulated the mRNA and protein levels of Nrf2 and its downstream target genes heme oxygenase-1 (HO-1) and
NAD(P)H: quinone oxidoreductase 1 (NQO1), while it only increased the protein level of UDP-glucuronosyltransferase 1A1 (UGT1A1). Furthermore, reserpine decreased the TPA (12-O-tetradecanoylphorbol-13-acetate)-induced colony formation of JB6 cells in a dose-dependent manner. DNA sequencing and methylated DNA immunoprecipitation further demonstrated the demethylation effect of reserpine on the first 15 CpGs of the Nrf2 promoter in JB6 P+ cells. Reserpine also reduced the mRNA and protein expression of DNMT1 (DNA methyltransferase 1), DNMT3a (DNA methyltransferases 3a), and DNMT3b (DNA methyltransferases 3b). Moreover, reserpine induced Nrf2 expression via an epigenetic pathway in skin epidermal JB6 P+ cells, enhancing the protective antioxidant activity and decreasing TPA-induced cell transformation. These results suggest that reserpine exhibits a cancer preventive effect by reactivating Nrf2 and inducing the expression of target genes involved in cellular protection, potentially providing new insight into the chemoprevention of skin cancer using reserpine.

Shankar E, Song K, Corum SL, et al.
A Signaling Network Controlling Androgenic Repression of c-Fos Protein in Prostate Adenocarcinoma Cells.
J Biol Chem. 2016; 291(11):5512-26 [PubMed] Article available free on PMC after 17/03/2017 Related Publications
The transcription factor c-Fos controls many important cellular processes, including cell growth and apoptosis. c-Fos expression is rapidly elevated in the prostate upon castration-mediated androgen withdrawal through an undefined mechanism. Here we show that androgens (5α-dihydrotestosterone and R1881) suppress c-Fos protein and mRNA expression induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) or EGF in human prostate cancer (PCa) cell lines. Such suppression transpires through a transcriptional mechanism, predominantly at the proximal serum response element of the c-fos promoter. We show that androgen signaling suppresses TPA-induced c-Fos expression through repressing a PKC/MEK/ERK/ELK-1 signaling pathway. Moreover, our results support the hypothesis that p38(MAPK), PI3K, and PKCδ are involved in the androgenic regulation of c-Fos through controlling MEK/ERK. Stable silencing of c-Fos and PKCδ with shRNAs suggests that R1881 promotes cell death induced by low-dose TPA through a mechanism that is dependent on both PKCδ and loss of c-Fos expression. Reciprocally, loss of either PKCδ or c-Fos activates p38(MAPK) while suppressing the activation of ERK1/2. We also provide the first demonstration that R1881 permits cell death induced by low-dose TPA in the LNCaP androgen-dependent PCa cell line and that TPA-induced cell death is independent of exogenous androgen in the castration-resistant variants of LNCaP, C4-2 and C4-2B. Acquisition of androgen-independent killing by TPA correlates with activation of p38(MAPK), suppression of ERK1/2, and loss of c-Fos. These results provide new insights into androgenic control of c-Fos and use of PKC inhibitors in PCa therapy.

Kim JM, Noh EM, Kim HR, et al.
Suppression of TPA-induced cancer cell invasion by Peucedanum japonicum Thunb. extract through the inhibition of PKCα/NF-κB-dependent MMP-9 expression in MCF-7 cells.
Int J Mol Med. 2016; 37(1):108-14 [PubMed] Article available free on PMC after 17/03/2017 Related Publications
Metastatic cancers spread from their site of origin (the primary site) to other parts of the body. Matrix metalloproteinase-9 (MMP-9), which degrades the extracellular matrix, is important in metastatic cancers as it plays a major role in cancer cell invasion. The present study examined the inhibitory effect of an ethanol extract of Peucedanum japonicum Thunb. (PJT) on MMP-9 expression and the invasion of MCF-7 breast cancer cells induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). Western blot analysis, gelatin zymography, and reverse transcription-quantitative PCR revealed that PJT significantly suppressed MMP-9 expression and activation in a dose-dependent manner. Furthermore, PJT attenuated TPA-induced nuclear translocation and the transcriptional activation of nuclear factor (NF)-κB. The results indicated that the PJT-mediated inhibition of TPA-induced MMP-9 expression and cell invasion involved the suppression of the PKCα/NF-κB pathway in MCF-7 cells. Thus, the inhibition of MMP-9 expression by PJT may have potential value as a therapy for restricting the invasiveness of breast cancer.

Cheng XB, Kohi S, Koga A, et al.
Hyaluronan stimulates pancreatic cancer cell motility.
Oncotarget. 2016; 7(4):4829-40 [PubMed] Article available free on PMC after 17/03/2017 Related Publications
Hyaluronan (HA) accumulates in pancreatic ductal adenocarcinoma (PDAC), but functional significance of HA in the aggressive phenotype remains unknown. We used different models to investigate the effect of HA on PDAC cell motility by wound healing and transwell migration assay. Changes in cell motility were examined in 8 PDAC cell lines in response to inhibition of HA production by treatment with 4-methylumbelliferone (4-MU) and to promotion by treatment with 12-O-tetradecanoyl-phorbol-13-acetate (TPA) or by co-culture with tumor-derived stromal fibroblasts. We also investigated changes in cell motility by adding exogenous HA. Additionally, mRNA expressions of hyaluronan synthases and hyaluronidases were examined using real time RT-PCR. Inhibition of HA by 4-MU significantly decreased the migration, whereas promotion of HA by TPA or co-culture with tumor-derived fibroblasts significantly increased the migration of PDAC cells. The changes in HA production by these treatments tended to be associated with changes in HAS3 mRNA expression. Furthermore, addition of exogenous HA, especially low-molecular-weight HA, significantly increased the migration of PDAC cells. These findings suggest that HA stimulates PDAC cell migration and thus represents an ideal therapeutic target to prevent invasion and metastasis.

Ecke TH
Biomarker in Cisplatin-Based Chemotherapy for Urinary Bladder Cancer.
Adv Exp Med Biol. 2015; 867:293-316 [PubMed] Related Publications
The treatment of metastasized bladder cancer has been evolving during recent years. Cisplatin based chemotherapy combinations are still gold standard in the treatment of advanced and metastasized bladder cancer. But new therapies are approaching. Based to this fact biological markers will become more important for decisions in bladder cancer treatment. A systematic MEDLINE search of the key words "cisplatin", "bladder cancer", "DNA marker", "protein marker", "methylation biomarker", "predictive marker", "prognostic marker" has been made. This review aims to highlight the most relevant clinical and experimental studies investigating markers for metastasized transitional carcinoma of the urothelium treated by cisplatin based regimens.

Lu S, Yang Y, Du Y, et al.
The transcription factor c-Fos coordinates with histone lysine-specific demethylase 2A to activate the expression of cyclooxygenase-2.
Oncotarget. 2015; 6(33):34704-17 [PubMed] Article available free on PMC after 17/03/2017 Related Publications
Cyclooxygenase-2 (COX-2) is overexpressed in a variety of human epithelial cancers, including lung cancer, and is highly associated with a poor prognosis and a low survival rate. Understanding how COX-2 is regulated in response to carcinogens will offer insight into designing anti-cancer strategies and preventing cancer development. Here, we analyzed COX-2 expression in several human lung cancer cell lines and found that COX-2 expression was absent in the H719 and H460 cell lines by a DNA methylation-independent mechanism. The re-expression of COX-2 was observed after 12-O-tetradecanoylphorbol-13-acetate (TPA) treatment in both cell lines. Further investigation found that H3K36 dimethylation was significantly reduced near the COX-2 promoter because histone demethylase 2A (KDM2A) was recruited to the COX-2 promoter after TPA treatment. In addition, the transcription factor c-Fos was found to be required to recruit KDM2A to the COX-2 promoter for reactivation of COX-2 in response to TPA treatment in both the H719 and H460 cell lines. Together, our data reveal a novel mechanism by which the carcinogen TPA activates COX-2 expression by regulating H3K36 dimethylation near the COX-2 promoter.

Kristiansen S, Jørgensen LM, Hansen MH, et al.
Concordance of Hypermethylated DNA and the Tumor Markers CA 15-3, CEA, and TPA in Serum during Monitoring of Patients with Advanced Breast Cancer.
Biomed Res Int. 2015; 2015:986024 [PubMed] Article available free on PMC after 17/03/2017 Related Publications
The serological protein tumor markers CA 15-3, CEA, and TPA are frequently used to monitor tumor burden among metastatic breast cancer patients. Breast cancer is associated with global DNA hypomethylation and hypermethylation of some promoter regions. No monitoring study has yet investigated the interrelationship between protein tumor markers, the global DNA hypomethylation, and hypermethylated genes in serum from patients with advanced disease. Twenty-nine patients with histologically proven advanced breast cancer received first-line chemotherapy with epirubicin. Samples were collected prior to each treatment and prospectively analyzed for CA 15-3, CEA, and TPA. The same samples were retrospectively analyzed for the concentration of hypermethylated RASSF1A and for global DNA hypomethylation using LINE-1. Among patients with elevated concentrations of the protein markers, concordance could be observed between serial changes of the hypermethylated RASSF1A gene and the protein markers. Among patients with lower concentrations, RASSF1A could only be detected periodically. There was discordance between changes of the hypomethylated LINE-1 as compared to the protein markers. Circulating hypermethylated RASSF1A and protein markers may have similar kinetics during monitoring of tumor burden. Further investigations are needed to determine whether any of the hypermethylated DNA genes may provide predictive information during monitoring.

Dahlhoff M, Schäfer M, Muzumdar S, et al.
ERBB3 is required for tumor promotion in a mouse model of skin carcinogenesis.
Mol Oncol. 2015; 9(9):1825-33 [PubMed] Related Publications
The epidermal growth factor receptor (EGFR) plays a key role in skin inflammation, wound healing, and carcinogenesis. Less is known about the functions of the structurally related receptor ERBB3 (HER3) in the skin. We assessed the requirement of ERBB3 for skin homeostasis, wound healing, and tumorigenesis by crossing mice carrying a conditional Erbb3 allele with animals expressing cre under the control of the keratin 5 promoter. Erbb3(del) mice, lacking ERBB3 specifically in keratinocytes, showed no obvious abnormalities. The EGFR was upregulated in Erbb3(del) skin, possibly compensating the loss of ERBB3. Nonetheless, healing of full-thickness excisional wounds was negatively affected by ERBB3 deficiency. To analyze the function of ERBB3 during tumorigenesis, we employed the established DMBA/TPA multi-stage chemical carcinogenesis protocol. Erbb3(del) mice remained free of papillomas for a longer time and had significantly reduced tumor burden compared to control littermates. Tumor cell proliferation was considerably reduced in Erbb3(del) mice, and loss of ERBB3 also impaired keratinocyte proliferation after a single application of TPA. In human skin tumor samples, upregulated ERBB3 expression was observed in squamous cell carcinoma, condyloma, and malignant melanoma. Thus, we conclude that ERBB3, while dispensable for the development and the homeostasis of the epidermis and its appendages, is required for proper wound healing and for the progression of skin tumors during multi-stage chemical carcinogenesis in mice. ERBB3 may also be important for human skin cancer progression. The latter effects most probably reflect a key role for ERBB3 in increasing cell proliferation after stimuli as wounding or carcinogenesis.

Meves A, Nikolova E, Heim JB, et al.
Tumor Cell Adhesion As a Risk Factor for Sentinel Lymph Node Metastasis in Primary Cutaneous Melanoma.
J Clin Oncol. 2015; 33(23):2509-15 [PubMed] Article available free on PMC after 17/03/2017 Related Publications
PURPOSE: Less than 20% of patients with melanoma who undergo sentinel lymph node (SLN) biopsy based on American Society of Clinical Oncology/Society of Surgical Oncology recommendations are SLN positive. We present a multi-institutional study to discover new molecular risk factors associated with SLN positivity in thin and intermediate-thickness melanoma.
PATIENTS AND METHODS: Gene clusters with functional roles in melanoma metastasis were discovered by next-generation sequencing and validated by quantitative polymerase chain reaction using a discovery set of 73 benign nevi, 76 primary cutaneous melanoma, and 11 in-transit melanoma metastases. We then used polymerase chain reaction to quantify gene expression in a model development cohort of 360 consecutive thin and intermediate-thickness melanomas and a validation cohort of 146 melanomas. Outcome of interest was SLN biopsy metastasis within 90 days of melanoma diagnosis. Logic and logistic regression analyses were used to develop a model for the likelihood of SLN metastasis from molecular, clinical, and histologic variables.
RESULTS: ITGB3, LAMB1, PLAT, and TP53 expression were associated with SLN metastasis. The predictive ability of a model that included these molecular variables in combination with clinicopathologic variables (patient age, Breslow depth, and tumor ulceration) was significantly greater than a model that only considered clinicopathologic variables and also performed well in the validation cohort (area under the curve, 0.93; 95% CI, 0.87 to 0.97; false-positive and false-negative rates of 22% and 0%, respectively, using a 10% cutoff for predicted SLN metastasis risk).
CONCLUSION: The addition of cell adhesion-linked gene expression variables to clinicopathologic variables improves the identification of patients with SLN metastases within 90 days of melanoma diagnosis.

Ghazavi F, Clappier E, Lammens T, et al.
CD200/BTLA deletions in pediatric precursor B-cell acute lymphoblastic leukemia treated according to the EORTC-CLG 58951 protocol.
Haematologica. 2015; 100(10):1311-9 [PubMed] Article available free on PMC after 17/03/2017 Related Publications
DNA copy number analysis has been instrumental for the identification of genetic alterations in B-cell precursor acute lymphoblastic leukemia. Notably, some of these genetic defects have been associated with poor treatment outcome and might be relevant for future risk stratification. In this study, we characterized recurrent deletions of CD200 and BTLA genes, mediated by recombination-activating genes, and used breakpoint-specific polymerase chain reaction assay to screen a cohort of 1154 cases of B-cell precursor acute lymphoblastic leukemia uniformly treated according to the EORTC-CLG 58951 protocol. CD200/BTLA deletions were identified in 56 of the patients (4.8%) and were associated with an inferior 8-year event free survival in this treatment protocol [70.2% ± 1.2% for patients with deletions versus 83.5% ± 6.4% for non-deleted cases (hazard ratio 2.02; 95% confidence interval 1.23-3.32; P=0.005)]. Genetically, CD200/BTLA deletions were strongly associated with ETV6-RUNX1-positive leukemias (P<0.0001), but were also identified in patients who did not have any genetic abnormality that is currently used for risk stratification. Within the latter population of patients, the presence of CD200/BTLA deletions was associated with inferior event-free survival and overall survival. Moreover, the multivariate Cox model indicated that these deletions had independent prognostic impact on event-free survival when adjusting for conventional risk criteria. All together, these findings further underscore the rationale for copy number profiling as an important tool for risk stratification in human B-cell precursor acute lymphoblastic leukemia. This trial was registered at www.ClinicalTrials.gov as #NCT00003728.

Banskota S, Regmi SC, Kim JA
NOX1 to NOX2 switch deactivates AMPK and induces invasive phenotype in colon cancer cells through overexpression of MMP-7.
Mol Cancer. 2015; 14:123 [PubMed] Article available free on PMC after 17/03/2017 Related Publications
BACKGROUND: Although matrix metalloproteinase (MMP)-7 expression is correlated with increased metastatic potential in human colon cancer cells, the underlying molecular mechanism of invasive phenotype remains unknown. In the current study, we investigated the regulatory effects of membrane NADPH oxidase (NOX) and AMP activated protein kinase (AMPK) on MMP-7 expression and invasive phenotype change in colon cancer cells.
METHODS: Production of superoxide anion was measured by lucigenin chemiluminescence assay using whole cells and protein extracts (NADPH oxidase activity), and intracellular reactive oxygen species (ROS) by fluorescence microscopy using 2',7'-dichlorofluorescein diacetate (DCF-DA). Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting were used to measure mRNA and protein levels, respectively. siRNA transfection was used to assess involvement of genes in cancer invasion, which were identified by Matrigel transwell invasion assay. Luciferase reporter assay was performed to identify transcription factors linked to gene expression.
RESULTS: Under basal conditions, less invasive human colon cancer cells (HT29 and Caco-2) showed low MMP-7 expression but high NOX1 expression and AMPK phosphorylation. Treatment of HT29 and Caco-2 cells with 12-O-tetradecanoylphorbol-13-acetate (TPA) induced an invasive phenotype response along with corresponding increases in ROS production and NOX2 and MMP-7 expression as well as reduced AMPK phosphorylation, which resemble basal conditions of highly invasive human colon cancer cells (SW620 and HCT116). In addition, inverse regulation between AMPK phosphorylation and NOX2 and MMP-7 expression was observed in HT29 cells treated with different concentrations of exogenous hydrogen peroxide. TPA-induced invasive phenotype in HT29 cells was abolished by treatment with Vit. E, DPI, apocynin, and NOX2 siRNA but not NOX1 siRNA, indicating NOX2-derived ROS production induced an invasive phenotype. TPA-induced induction of MMP-7 expression was suppressed by AP-1, NF-κB, and MAPK (ERK, p38, and JNK) inhibitors, whereas TPA-induced expression of NOX2 and its regulators, p47phox and p67phox, was blocked by p38 and NF-κB inhibitors.
CONCLUSIONS: Molecular switch from NOX1 to NOX2 in colon cancer cells induces ROS production and subsequently enhances MMP-7 expression by deactivating AMPK, which otherwise inhibits stimulus-induced autoregulation of ROS and NOX2 gene expression.

Noh EM, Park YJ, Kim JM, et al.
Fisetin regulates TPA-induced breast cell invasion by suppressing matrix metalloproteinase-9 activation via the PKC/ROS/MAPK pathways.
Eur J Pharmacol. 2015; 764:79-86 [PubMed] Related Publications
Invasion and metastasis are among the main causes of death in patients with malignant tumors. Fisetin (3,3',4',7-tetrahydroxyflavone), a natural flavonoid found in the smoke tree (Cotinus coggygria), is known to have antimetastatic effects on prostate and lung cancers; however, the effect of fisetin on breast cancer metastasis is unknown. The aim of this study was to determine the anti-invasive activity of fisetin in human breast cancer cells. Matrix metalloproteinase (MMP)-9 is a major component facilitating the invasion of many cancer tumor cell types, and thus the inhibitory effect of fisetin on MMP-9 expression in 12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated human breast cancer cells was investigated in this study. Fisetin significantly attenuated TPA-induced cell invasion in MCF-7 human breast cancer cells, and was found to inhibit the activation of the PKCα/ROS/ERK1/2 and p38 MAPK signaling pathways. This effect was furthermore associated with reduced NF-κB activation, suggesting that the anti-invasive effect of fisetin on MCF-7 cells may result from inhibited TPA activation of NF-κB and reduced TPA activation of PKCα/ROS/ERK1/2 and p38 MAPK signals, ultimately leading to the downregulation of MMP-9 expression. Our findings indicate the role of fisetin in MCF-7 cell invasion, and clarify the underlying molecular mechanisms of this role, suggesting fisetin as a potential chemopreventive agent for breast cancer metastasis.

Kanno T, Uehara T, Osawa M, et al.
Fumagillin, a potent angiogenesis inhibitor, induces Kaposi sarcoma-associated herpesvirus replication in primary effusion lymphoma cells.
Biochem Biophys Res Commun. 2015; 463(4):1267-72 [PubMed] Related Publications
Kaposi sarcoma and primary effusion lymphoma cells are infected with Kaposi sarcoma-associated herpesvirus (KSHV), predominantly in the latent form, and KSHV replication is observed rarely. Angiogenesis plays a crucial role in the pathogenesis of both Kaposi sarcoma and primary effusion lymphoma. In this study, we found that fumagillin, a potent angiogenesis inhibitor, induced replication of KSHV in primary effusion lymphoma cell lines. The transcript and protein product of replication transcriptional activator (RTA) were induced by 1-10 μM fumagillin at 24 and 48 h, respectively. Western blot analysis demonstrated that 10 μM fumagillin induced not only RTA expression but also other KSHV-encoded lytic proteins. A real-time PCR array detecting KSHV gene expression demonstrated that the expression profiles of KSHV induced by fumagillin were similar to those induced by 12-O-tetradecanoylphorbol-13-acetate (TPA), but the amounts of each transcript were lower than those induced by TPA. Finally, real-time PCR demonstrated an increase in that viral DNA copy number per cell in fumagillin-stimulated primary effusion lymphoma cell lines, indicating replication of KSHV. In addition to TPA, 10 μM fumagillin resulted in growth inhibition of primary effusion lymphoma cell lines. These observations suggest that an angiogenesis inhibitor is an agent with potent effects on cell growth and KSHV reactivation in primary effusion lymphoma cells.

Diaz-Valdivia N, Bravo D, Huerta H, et al.
Enhanced caveolin-1 expression increases migration, anchorage-independent growth and invasion of endometrial adenocarcinoma cells.
BMC Cancer. 2015; 15:463 [PubMed] Article available free on PMC after 17/03/2017 Related Publications
BACKGROUND: Caveolin-1 (CAV1) has been implicated both in tumor suppression and progression, whereby the specific role appears to be context dependent. Endometrial cancer is one of the most common malignancies of the female genital tract; however, little is known about the role of CAV1 in this disease.
METHODS: Here, we first determined by immunohistochemistry CAV1 protein levels in normal proliferative human endometrium and endometrial tumor samples. Then using two endometrial cancer cell lines (ECC: Ishikawa and Hec-1A) we evaluated mRNA and protein levels of CAV1 by real time qPCR and Western blot analysis, respectively. The role of CAV1 expression in ECC malignancy was further studied by either inducing its expression in endometrial cancer cells with the tumor promotor 12-O-tetradecanoyl-phorbol-13-acetate (4β-TPA) or decreasing expression using short-hairpin RNA constructs, and then evaluating the effects of these changes on ECC proliferation, transmigration, matrigel invasion, and colony formation in soft agar.
RESULTS: Immunohistochemical analysis of endometrial epithelia revealed that substantially higher levels of CAV1 were present in endometrial tumors than the normal proliferative epithelium. Also, in Ishikawa and Hec-1A endometrial cancer cells CAV1 expression was readily detectable. Upon treatment with 4β-TPA CAV1 levels increased and coincided with augmented cell transmigration, matrigel invasion, as well as colony formation in soft agar. Reduction of CAV1 expression using short-hairpin RNA constructs ablated these effects in both cell types whether treated or not with 4β-TPA. Alternatively, CAV1 expression appeared not to modulate significantly proliferation of these cells.
CONCLUSION: Our study shows that elevated CAV1, observed in patients with endometrial cancer, is linked to enhanced malignancy of endometrial cancer cells, as evidenced by increased migration, invasion and anchorage-independent growth.

Clappier E, Grardel N, Bakkus M, et al.
IKZF1 deletion is an independent prognostic marker in childhood B-cell precursor acute lymphoblastic leukemia, and distinguishes patients benefiting from pulses during maintenance therapy: results of the EORTC Children's Leukemia Group study 58951.
Leukemia. 2015; 29(11):2154-61 [PubMed] Related Publications
The added value of IKZF1 gene deletion (IKZF1(del)) as a stratifying criterion in B-cell precursor acute lymphoblastic leukemia (BCP-ALL) is still debated. We performed a comprehensive analysis of the impact of IKZF1(del) in a large cohort of children (n=1223) with BCR-ABL1-negative BCP-ALL treated in the EORTC-CLG trial 58951. Patients with IKZF1(del) had a lower 8-year event-free survival (EFS, 67.7% versus 86.5%; hazard ratio (HR)=2.41; 95% confidence interval (CI)=1.75-3.32; P<0.001). Importantly, despite association with high-risk features such as high minimal residual disease, IKZF1(del) remained significantly predictive in multivariate analyses. Analysis by genetic subtype showed that IKZF1(del) increased risk only in the high hyperdiploid ALLs (HR=2.57; 95% CI=1.19-5.55; P=0.013) and in 'B-other' ALLs, that is, lacking classifying genetic lesions (HR=2.22; 95% CI=1.45-3.39; P<0.001), the latter having then a dramatically low 8-year EFS (56.4; 95% CI=44.6-66.7). Among IKZF1(del)-positive patients randomized for vincristine-steroid pulses during maintenance, those receiving pulses had a significantly higher 8-year EFS (93.3; 95% CI=61.3-99.0 versus 42.1; 95% CI=20.4-62.5). Thus, IKZF1(del) retains independent prognostic significance in the context of current risk-adapted protocols, and is associated with a dismal outcome in 'B-other' ALL. Addition of vincristine-steroid pulses during maintenance may specifically benefit to IKZF1(del) patients in preventing relapses.

Noh EM, Lee YR, Hong OY, et al.
Aurora kinases are essential for PKC-induced invasion and matrix metalloproteinase-9 expression in MCF-7 breast cancer cells.
Oncol Rep. 2015; 34(2):803-10 [PubMed] Related Publications
The Aurora kinase family of serine/threonine kinases are known to be crucial for cell cycle control. Aurora kinases are considered a target of anticancer drugs. However, few studies have assessed the effect of Aurora kinases in breast cancer. In the present study, to determine whether Aurora kinases play a role in oncogenic actions of protein kinase C (PKC), we investigated the effect of Aurora kinases on PKC-induced invasion and MMP-9 expression using breast cancer cells. Treatment of MCF-7 cells with 12-O-tetradecanoylphorbol-13-acetate (TPA) induced the upregulation and phosphorylation of Aurora kinases via the MAPK signaling pathway. Moreover, the inhibition of Aurora kinases by their siRNAs and inhibitors suppressed TPA-induced cell invasion and expression of MMP-9 by inhibiting the activation of NF-κB/AP-1, major transcription factors for MMP-9 expression in MCF-7 cells. These results suggested that Aurora kinases mediate PKC-MAPK signal to NF-κB/AP-1 with increasing MMP-9 expression and invasion of MCF-7 cells. To the best of our knowledge, this is the first study to show that Aurora kinases are key molecules in PKC-induced invasion in breast cancer cells.

Zhang XD, Xie JJ, Liao LD, et al.
12-O-Tetradecanoylphorbol-13-Acetate Induces Up-Regulated Transcription of Variant 1 but Not Variant 2 of VIL2 in Esophageal Squamous Cell Carcinoma Cells via ERK1/2/AP-1/Sp1 Signaling.
PLoS One. 2015; 10(4):e0124680 [PubMed] Article available free on PMC after 17/03/2017 Related Publications
The membrane-cytoskeleton link organizer ezrin may be the most "dramatic" tumor marker, being strongly over-expressed in nearly one-third of human malignancies. However, the molecular mechanisms of aberrant ezrin expression still need to be clarified. Ezrin, encoded by the VIL2 gene, has two transcript variants that differ in the transcriptional start site (TSS): V1 and V2. Both V1 and V2 encode the same protein. Here, we found that 12-O-tetradecanoylphorbol-13-acetate (TPA) induced over-expression of human VIL2 in esophageal squamous cell carcinoma (ESCC) cells. Furthermore, VIL2 V1 but not V2 was up-regulated after TPA stimulation in a time-dependent manner. AP-1 and Sp1 binding sites within the promoter region of VIL2 V1 acted not only as basal transcriptional elements but also as a composite TPA-responsive element (TRE) for the transcription of VIL2 V1. TPA stimulation enhanced c-Jun and Sp1 binding to the TRE via activation of the ERK1/2 pathway and increased protein levels of c-Jun, c-Fos, and Sp1, resulting in over-expression of VIL2 V1, whereas the MEK1/2 inhibitor U0126 blocked these events. Finally, we showed that TPA promoted the migration of ESCC cells whereas MEK1/2 inhibitor or ezrin silencing could partially inverse this alteration. Taken together, these results suggest that TPA is able to induce VIL2 V1 over-expression in ESCC cells by activating MEK/ERK1/2 signaling and increasing binding of Sp1 and c-Jun to the TRE of the VIL2 V1 promoter, and that VIL2 is an important TPA-induced effector.

Li L, Dang Y, Zhang J, et al.
REGγ is critical for skin carcinogenesis by modulating the Wnt/β-catenin pathway.
Nat Commun. 2015; 6:6875 [PubMed] Related Publications
Here we report that mice deficient for the proteasome activator, REGγ, exhibit a marked resistance to TPA (12-O-tetradecanoyl-phorbol-13-acetate)-induced keratinocyte proliferation, epidermal hyperplasia and onset of papillomas compared with wild-type counterparts. Interestingly, a massive increase of REGγ in skin tissues or cells resulting from TPA induces activation of p38 mitogen-activated protein kinase (MAPK/p38). Blocking p38 MAPK activation prevents REGγ elevation in HaCaT cells with TPA treatment. AP-1, the downstream effector of MAPK/p38, directly binds to the REGγ promoter and activates its transcription in response to TPA stimulation. Furthermore, we find that REGγ activates Wnt/β-catenin signalling by degrading GSK-3β in vitro and in cells, increasing levels of CyclinD1 and c-Myc, the downstream targets of β-catenin. Conversely, MAPK/p38 inactivation or REGγ deletion prevents the increase of cyclinD1 and c-Myc by TPA. This study demonstrates that REGγ acts in skin tumorigenesis mediating MAPK/p38 activation of the Wnt/β-catenin pathway.

Shin EJ, Sung MJ, Park JH, et al.
Poly-γ-glutamic acid induces apoptosis via reduction of COX-2 expression in TPA-induced HT-29 human colorectal cancer cells.
Int J Mol Sci. 2015; 16(4):7577-86 [PubMed] Article available free on PMC after 17/03/2017 Related Publications
Poly-γ-glutamic acid (PGA) is one of the bioactive compounds found in cheonggukjang, a fast-fermented soybean paste widely utilized in Korean cooking. PGA is reported to have a number of beneficial health effects, and interestingly, it has been identified as a possible anti-cancer compound through its ability to promote apoptosis in cancer cells, although the precise molecular mechanisms remain unclear. Our findings demonstrate that PGA inhibits the pro-proliferative functions of the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA), a known chemical carcinogen in HT-29 human colorectal cancer cells. This inhibition was accompanied by hallmark apoptotic phenotypes, including DNA fragmentation and the cleavage of poly (ADP-ribose) polymerase (PARP) and caspase 3. In addition, PGA treatment reduced the expression of genes known to be overexpressed in colorectal cancer cells, including cyclooxygenase 2 (COX-2) and inducible nitric oxide synthase (iNOS). Lastly, PGA promoted activation of 5' adenosine monophosphate-activated protein (AMPK) in HT-29 cells. Taken together, our results suggest that PGA treatment enhances apoptosis in colorectal cancer cells, in part by modulating the activity of the COX-2 and AMPK signaling pathways. These anti-cancer functions of PGA make it a promising compound for future study.

Huang H, Cao K, Malik S, et al.
Combination of 12-O-tetradecanoylphorbol-13-acetate with diethyldithiocarbamate markedly inhibits pancreatic cancer cell growth in 3D culture and in immunodeficient mice.
Int J Mol Med. 2015; 35(6):1617-24 [PubMed] Article available free on PMC after 17/03/2017 Related Publications
The aim of the present study was to determine the effects of 12-O-tetradecanoylphorbol-13-acetate (TPA) and diethyldithiocarbamate (DDTC) alone or in combination on human pancreatic cancer cells cultured in vitro and grown as xenograft tumors in nude mice. Pancreatic cancer cells were treated with either DDTC or TPA alone, or in combination and the number of viable cells was then determined by trypan blue ecxlusion assay and the number of apoptotic cells was determined by morphological assessment by staining the cells with propidium idiode and examining them under a fluorescence microscope. Treatment with DDTC or TPA alone inhibited the growth and promoted the apoptosis of pancreatic cancer cells in a concentration-dependent manner. These effects were more prominent following treatment with TPA in combination with DDTC than following treatment with either agent alone in PANC-1 cells in monolayer cultures and in 3 dimensional (3D) cultures. The potent effects of the combination treatment on PANC-1 cells were associated with the inhibition of nuclear factor-κB (NF-κB) activation and the decreased expression of Bcl-2 induced by DDTC, as shown by NF-κB-dependent reporter gene expression assay and western blot analysis. Furthermore, treatment of nude mice with DDTC + TPA strongly inhibited the growth of PANC-1 xenograft tumors. The results of the present study indicate that the administration of TPA and DDTC in combination may be an effective strategy for inhibiting the growth of pancreatic cancer.

Ha BG, Park JE, Cho HJ, et al.
Inhibitory effects of proton beam irradiation on integrin expression and signaling pathway in human colon carcinoma HT29 cells.
Int J Oncol. 2015; 46(6):2621-8 [PubMed] Related Publications
Proton radiotherapy has been established as a highly effective modality used in the local control of tumor growth. Although proton radiotherapy is used worldwide to treat several types of cancer clinically with great success due to superior targeting and energy deposition, the detailed regulatory mechanisms underlying the functions of proton radiation are not yet well understood. Accordingly, in the present study, to assess the effects of proton beam on integrin-mediated signaling pathways, we investigated the expression of integrins related to tumor progression and integrin trafficking, and key molecules related to cell adhesion, as well as examining phosphorylation of signaling molecules involved in integrin-mediated signaling pathways. Proton beam irradiation inhibited the increase in 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced integrin β1 protein expression and the gene expression of members of the integrin family, such as α5β1, α6β4, αvβ3, and αvβ6 in human colorectal adenocarcinoma HT-29 cells. Simultaneously, the gene expression of cell adhesion molecules, such as FAK and CDH1, and integrin trafficking regulators, such as RAB4, RAB11, and HAX1, was decreased by proton beam irradiation. Moreover, proton beam irradiation decreased the phosphorylation of key molecules involved in integrin signaling, such as FAK, Src, and p130Cas, as well as PKC and MAPK, which are known as promoters of cell migration, while increased the phosphorylation of AMPK and the gene expression of Rab IP4 involved in the inhibition of cell adhesion and cell spreading. Taken together, our findings suggest that proton beam irradiation can inhibit metastatic potential, including cell adhesion and migration, by modulating the gene expression of molecules involved in integrin trafficking and integrin-mediated signaling, which are necessary for tumor progression.

Bellezza I, Gatticchi L, del Sordo R, et al.
The loss of Tm7sf gene accelerates skin papilloma formation in mice.
Sci Rep. 2015; 5:9471 [PubMed] Article available free on PMC after 17/03/2017 Related Publications
The 3β-hydroxysterol Δ14-reductase, encoded by the Tm7sf2 gene, is an enzyme involved in cholesterol biosynthesis. Cholesterol and its derivatives control epidermal barrier integrity and are protective against environmental insults. To determine the role of the gene in skin cholesterol homeostasis, we applied 12-o-tetradecanoylphorbol-13-acetate (TPA) to the skin of Tm7sf2(+/+) and Tm7sf2(-/-) mice. TPA increased skin cholesterol levels by inducing de novo synthesis and up-take only in Tm7sf2(+/+) mouse, confirming that the gene maintains cholesterol homeostasis under stress conditions. Cholesterol sulfate, one of the major players in skin permeability, was doubled by TPA treatment in the skin of wild-type animals but this response was lost in Tm7sf2(-/-) mice. The expression of markers of epidermal differentiation concomitant with farnesoid-X-receptor and p38 MAPK activation were also disrupted in Tm7sf2(-/-) mice. We then subjected Tm7sf2(+/+) and Tm7sf2(-/-) mice to a classical two-stage skin carcinogenesis protocol. We found that the loss of Tm7sf2 increased incidence and multiplicity of skin papillomas. Interestingly, the null genotype showed reduced expression of nur77, a gene associated with resistance to neoplastic transformation. In conclusion, the loss of Tm7sf2 alters the expression of proteins involved in epidermal differentiation by reducing the levels of cholesterol sulfate.

Petti E, Jordi F, Buemi V, et al.
Altered telomere homeostasis and resistance to skin carcinogenesis in Suv39h1 transgenic mice.
Cell Cycle. 2015; 14(9):1438-46 [PubMed] Article available free on PMC after 17/03/2017 Related Publications
The Suv39h1 and Suv39h2 H3K9 histone methyltransferases (HMTs) have a conserved role in the formation of constitutive heterochromatin and gene silencing. Using a transgenic mouse model system we demonstrate that elevated expression of Suv39h1 increases global H3K9me3 levels in vivo. More specifically, Suv39h1 overexpression enhances the imposition of H3K9me3 levels at constitutive heterochromatin at telomeric and major satellite repeats in primary mouse embryonic fibroblasts. Chromatin compaction is paralleled by telomere shortening, indicating that telomere length is controlled by H3K9me3 density at telomeres. We further show that increased Suv39h1 levels result in an impaired clonogenic potential of transgenic epidermal stem cells and Ras/E1A transduced transgenic primary mouse embryonic fibroblasts. Importantly, Suv39h1 overexpression in mice confers resistance to a DMBA/TPA induced skin carcinogenesis protocol that is characterized by the accumulation of activating H-ras mutations. Our results provide genetic evidence that Suv39h1 controls telomere homeostasis and mediates resistance to oncogenic stress in vivo. This identifies Suv39h1 as an interesting target to improve oncogene induced senescence in premalignant lesions.

Lee JH, Kim JE, Jang YJ, et al.
Dehydroglyasperin C suppresses TPA-induced cell transformation through direct inhibition of MKK4 and PI3K.
Mol Carcinog. 2016; 55(5):552-62 [PubMed] Related Publications
Bioactive natural compounds from plant-derived sources have received substantial interest due to their potential therapeutic and preventive effects toward various human diseases. Licorice (Glycyrrhiza), a frequently-used component in traditional oriental medicines, has been incorporated into recipes not only to enhance taste, but also to treat various conditions including inflammation, chronic fatigue syndrome, and even cancer. Dehydroglyasperin C (DGC) is a major isoflavone found in the root of licorice. In the present study, we investigated the cancer chemopreventive effect of DGC and the underlying molecular mechanisms involved, by analyzing its effects on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced neoplastic cell transformation and cyclooxygenase (COX)-2 expression in JB6 P+ mouse epidermal cells. DGC treatment attenuated TPA-induced activator protein-1 (AP-1) and nuclear factor-κB (NF-κB) transcriptional activation, two major regulators of TPA-induced cell transformation, and COX-2 expression. TPA-induced phosphorylation of p38, JNK1/2 and Akt was also suppressed by DGC. Kinase assay data revealed that DGC inhibited the kinase activity of MKK4 and PI3K and this outcome was due to direct physical binding with DGC. Notably, DGC bound directly to MKK4 and PI3K in an ATP-competitive manner. Taken together, these results suggest that DGC exhibits cancer chemopreventive potential via its inhibitory effect on TPA-induced neoplastic cell transformation and COX-2 modulation through regulation of the MKK4 and PI3K pathways.

Kim KB, Son HJ, Choi S, et al.
H3K9 methyltransferase G9a negatively regulates UHRF1 transcription during leukemia cell differentiation.
Nucleic Acids Res. 2015; 43(7):3509-23 [PubMed] Article available free on PMC after 17/03/2017 Related Publications
Histone H3K9 methyltransferase (HMTase) G9a-mediated transcriptional repression is a major epigenetic silencing mechanism. UHRF1 (ubiquitin-like with PHD and ring finger domains 1) binds to hemimethylated DNA and plays an essential role in the maintenance of DNA methylation. Here, we provide evidence that UHRF1 is transcriptionally downregulated by H3K9 HMTase G9a. We found that increased expression of G9a along with transcription factor YY1 specifically represses UHRF1 transcription during TPA-mediated leukemia cell differentiation. Using ChIP analysis, we found that UHRF1 was among the transcriptionally silenced genes during leukemia cell differentiation. Using a DNA methylation profiling array, we discovered that the UHRF1 promoter was hypomethylated in samples from leukemia patients, further supporting its overexpression and oncogenic activity. Finally, we showed that G9a regulates UHRF1-mediated H3K23 ubiquitination and proper DNA replication maintenance. Therefore, we propose that H3K9 HMTase G9a is a specific epigenetic regulator of UHRF1.

Bouris P, Skandalis SS, Piperigkou Z, et al.
Estrogen receptor alpha mediates epithelial to mesenchymal transition, expression of specific matrix effectors and functional properties of breast cancer cells.
Matrix Biol. 2015; 43:42-60 [PubMed] Related Publications
The 17β-estradiol (E2)/estrogen receptor alpha (ERα) signaling pathway is one of the most important pathways in hormone-dependent breast cancer. E2 plays pivotal roles in cancer cell growth, survival, and architecture as well as in gene expression regulatory mechanisms. In this study, we established stably transfected MCF-7 cells by knocking down the ERα gene (designated as MCF-7/SP10+ cells), using specific shRNA lentiviral particles, and compared them with the control cells (MCF-7/c). Interestingly, ERα silencing in MCF-7 cells strongly induced cellular phenotypic changes accompanied by significant changes in gene and protein expression of several markers typical of epithelial to mesenchymal transition (EMT). Notably, these cells exhibited enhanced cell proliferation, migration and invasion. Moreover, ERα suppression strongly affected the gene and protein expression of EGFR and HER2 receptor tyrosine kinases, and various extracellular matrix (ECM) effectors, including matrix metalloproteinases and their endogenous inhibitors (MMPs/TIMPs) and components of the plasminogen activation system. The action caused by E2 in MCF-7/c cells in the expression of HER2, MT1-MMP, MMP1, MMP9, uPA, tPA, and PAI-1 was abolished in MCF-7/SP10+ cells lacking ERα. These data suggested a regulatory role for the E2/ERα pathway in respect to the composition and activity of the extracellular proteolytic molecular network. Notably, loss of ERα promoted breast cancer cell migration and invasion by inducing changes in the expression levels of certain matrix macromolecules (especially uPA, tPA, PAI-1) through the EGFR-ERK signaling pathway. In conclusion, loss of ERα in breast cancer cells results in a potent EMT characterized by striking changes in the expression profile of specific matrix macromolecules highlighting the potential nodal role of matrix effectors in breast cancer endocrine resistance.

Lee WT, Lee TH, Cheng CH, et al.
Antroquinonol from Antrodia Camphorata suppresses breast tumor migration/invasion through inhibiting ERK-AP-1- and AKT-NF-κB-dependent MMP-9 and epithelial-mesenchymal transition expressions.
Food Chem Toxicol. 2015; 78:33-41 [PubMed] Related Publications
Antroquinonol (ANQ) is an ubiquinon derivative isolated from the mycelium of Antrodia camphorata. However, the effect of ANQ on breast cancer treatment is unknown. We found that ANQ significantly suppressed the migration and invasion of breast cancer MDA-MB-231 cells, and inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced invasiveness by MCF7 cells. ANQ inhibiting MMP-9 gene expression and enzymatic activity occurred at transcriptional regulation. Mechanistically, activation of ERK and AKT is crucial for MMP-9 gene expression, and the addition of ANQ suppressed phosphorylation of ERK and AKT. The induction of the AP-1 and NF-κB pathway participated in MMP-9 gene expression. Suppression of ERK inhibited AP-1, whereas blocking AKT diminished NF-κB activity, and treatment with ANQ suppressed both AP-1 and NF-κB signaling. Moreover, ANQ suppressed EMT protein expression, and inhibited TPA-induced EMT through downregulating the ERK-AP-1 and AKT-NF-κB signaling cascades. Together, our data showed for the first time that ANQ inhibited breast cancer invasiveness by suppressing ERK-AP-1- and AKT-NF-κB-dependent MMP-9 and EMT expressions.

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