KAT5

Gene Summary

Gene:KAT5; lysine acetyltransferase 5
Aliases: TIP, ESA1, PLIP, TIP60, cPLA2, HTATIP, ZC2HC5, HTATIP1
Location:11q13.1
Summary:The protein encoded by this gene belongs to the MYST family of histone acetyl transferases (HATs) and was originally isolated as an HIV-1 TAT-interactive protein. HATs play important roles in regulating chromatin remodeling, transcription and other nuclear processes by acetylating histone and nonhistone proteins. This protein is a histone acetylase that has a role in DNA repair and apoptosis and is thought to play an important role in signal transduction. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, Jul 2008]
Databases:VEGA, OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:histone acetyltransferase KAT5
Source:NCBIAccessed: 09 March, 2017

Ontology:

What does this gene/protein do?
Show (25)
Pathways:What pathways are this gene/protein implicaed in?
Show (1)

Cancer Overview

Research Indicators

Publications Per Year (1992-2017)
Graph generated 10 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.

  • Messenger RNA
  • Thyrotropin
  • Immunohistochemistry
  • Cancer Gene Expression Regulation
  • Neoplasm Proteins
  • KAT5
  • Flow Cytometry
  • Lysine
  • Breast Cancer
  • Biomarkers, Tumor
  • Oligonucleotide Array Sequence Analysis
  • Down-Regulation
  • Promoter Regions
  • Chromosome 11
  • Cell Line
  • Histones
  • Nuclear Proteins
  • Thyroid Cancer
  • Protein Binding
  • Western Blotting
  • Neoplasm Invasiveness
  • Trans-Activators
  • Transfection
  • Acetyltransferases
  • Cell Proliferation
  • HEK293 Cells
  • Prostate Cancer
  • Histone Acetyltransferases
  • Antineoplastic Agents
  • Androgen Receptors
  • Acetylation
  • Bladder Cancer
  • Proto-Oncogene Proteins
  • Up-Regulation
  • Apoptosis
  • Gene Expression Profiling
  • Neoplastic Cell Transformation
  • DNA-Binding Proteins
  • RTPCR
  • Protein Processing, Post-Translational
  • Transcription
  • DNA Damage
Tag cloud generated 09 March, 2017 using data from PubMed, MeSH and CancerIndex

Specific Cancers (4)

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: KAT5 (cancer-related)

Powers S, Pollack RE
Inducing stable reversion to achieve cancer control.
Nat Rev Cancer. 2016; 16(4):266-70 [PubMed] Related Publications
How can we stop cancer progression? Current strategies depend on modelling progression as the balanced outcome of mutations in, and expression of, tumour suppressor genes and oncogenes. New treatments emerge from successful attempts to tip that balance, but secondary mutational escape from those treatments has become a major impediment because it leads to resistance. In this Opinion article, we argue for a return to an earlier stratagem: tumour cell reversion. Treatments based on selection and analysis of stable revertants could create more durable remissions by reducing the selective pressure that leads to rapid drug resistance.

Thway K, Wren D, Lee J, et al.
Evaluation of the optimal provision of formalin-fixed, paraffin-embedded material for reverse transcription-PCR in soft-tissue tumour diagnosis.
J Clin Pathol. 2017; 70(1):20-24 [PubMed] Related Publications
AIMS: Molecular genetic analysis is now a routine ancillary diagnostic modality to the histopathological diagnosis of soft-tissue neoplasms, many of which harbour characteristic gene fusions detectable by reverse transcription-PCR (RT-PCR). As the final diagnosis often depends on the molecular result, it is important to obtain the optimal yield of patient RNA.
METHODS: We assessed the most reliable method of providing formalin-fixed, paraffin-embedded material for optimal RNA yield by comparing three consecutive periods in which different preparations (5×10 μm scrolls, 5×5 μm sections and 1×10 μm sections) were used for RNA extraction for RT-PCR, with its technical success rate.
RESULTS: For '2011', '2012' and '2013', RT-PCR technical failure rates were 13.4%, 4.4% and 7.9%, respectively. The percentage of failed referral cases was 71.4%, 85.7% and 31.3%, and the proportion of core biopsy to excision specimens was 3:15, 2:5 and 13:3.
CONCLUSIONS: This study shows that the effectiveness of RNA extraction and purification is dependent on both specimen type and the tissue sectioning strategy. The failure rate has improved over recent years, particularly for large specimens as large numbers of thick 10 μm scrolls can saturate RNA extraction columns. In contrast, recent technical fails are more frequent in core biopsies, where 1×10 μm sections are insufficient for adequate RNA extraction. While previous technical fails occurred mostly in referred cases, this appears no longer the case due to the better fixation and processing of specimens in external surgical pathology departments because of the widespread recognition of the importance of molecular diagnostics as an important part of the patient pathway.

Su J, Wang F, Cai Y, Jin J
The Functional Analysis of Histone Acetyltransferase MOF in Tumorigenesis.
Int J Mol Sci. 2016; 17(1) [PubMed] Free Access to Full Article Related Publications
Changes in chromatin structure and heritably regulating the gene expression by epigenetic mechanisms, such as histone post-translational modification, are involved in most cellular biological processes. Thus, abnormal regulation of epigenetics is implicated in the occurrence of various diseases, including cancer. Human MOF (males absent on the first) is a member of the MYST (Moz-Ybf2/Sas3-Sas2-Tip60) family of histone acetyltransferases (HATs). As a catalytic subunit, MOF can form at least two distinct multiprotein complexes (MSL and NSL) in human cells. Both complexes can acetylate histone H4 at lysine 16 (H4K16); however, the NSL complex possesses broader substrate specificity and can also acetylate histone H4 at lysines 5 and 8 (H4K5 and H4K8), suggesting the complexity of the intracellular functions of MOF. Silencing of MOF in cells leads to genomic instability, inactivation of gene transcription, defective DNA damage repair and early embryonic lethality. Unbalanced MOF expression and its corresponding acetylation of H4K16 have been found in certain primary cancer tissues, including breast cancer, medulloblastoma, ovarian cancer, renal cell carcinoma, colorectal carcinoma, gastric cancer, as well as non-small cell lung cancer. In this review, we provide a brief overview of MOF and its corresponding histone acetylation, introduce recent research findings that link MOF functions to tumorigenesis and speculate on the potential role that may be relevant to tumorigenic pathways.

Cregan S, McDonagh L, Gao Y, et al.
KAT5 (Tip60) is a potential therapeutic target in malignant pleural mesothelioma.
Int J Oncol. 2016; 48(3):1290-6 [PubMed] Related Publications
Malignant pleural mesothelioma (MPM) is a rare aggressive cancer of the pleura. Asbestos exposure (through inhalation) is the most well established risk factor for mesothelioma. The current standard of care for patients suffering from MPM is a combination of cisplatin and pemetrexed (or alternatively cisplatin and raltitrexed). Most patients, however, die within 24 months of diagnosis. New therapies are therefore urgently required for this disease. Lysine acetyltransferases (KATs) including KAT5 have been linked with the development of cisplatin resistance. This gene may therefore be altered in MPM and could represent a novel candidate target for intervention. Using RT-PCR screening the expression of all known KAT5 variants was found to be markedly increased in malignant tumors compared to benign pleura. When separated according to histological subtype, KAT5 was significantly overexpressed in both the sarcomatoid and biphasic subgroups for all transcript variants. A panel of MPM cell lines including the normal pleural cells LP9 and Met5A was screened for expression of KAT5 variants. Treatment of cells with a small molecule inhibitor of KAT5 (MG-149) caused significant inhibition of cellular proliferation (p<0.0001), induction of apoptosis and was accompanied by significant induction of pro-inflammatory cytokines/chemokines.

Lian Y, Ding J, Zhang Z, et al.
The long noncoding RNA HOXA transcript at the distal tip promotes colorectal cancer growth partially via silencing of p21 expression.
Tumour Biol. 2016; 37(6):7431-40 [PubMed] Related Publications
Accumulating evidence strongly suggests that dysregulation of long noncoding RNAs (lncRNAs) is associated with human carcinogenesis. The lncRNA HOXA transcript at the distal tip (HOTTIP) is involved in the development of several cancers. However, the biological role of HOTTIP in colorectal cancer (CRC) has not yet been discussed. Here, we report that HOTTIP acts as a functional oncogene in the pathogenesis of CRC. In this study, quantitative polymerase chain reaction (qPCR) was performed to detect the expression of HOTTIP in 48 pairs of colorectal cancer samples. We found that overexpression of HOTTIP is correlated with an advanced pathological stage and a larger tumor size. Moreover, functional analyses revealed that the knockdown of HOTTIP expression by small interfering RNA (siRNA) or small hairpin RNA (shRNA) could inhibit cell proliferation and induce cell apoptosis. More importantly, we observed that HOTTIP knockdown induced a marked increase in the number of cells in the G0/G1 phase and a reduction in the number of cells in the S phase in both DLD-1 cells and SW480 cells. An in vivo experiment also revealed that the knockdown of HOTTIP inhibited tumor growth. Western blot and immunohistochemistry analyses indicated that HOTTIP potentially contributed to CRC cell growth partially through the silencing of p21 expression. Collectively, our results suggest that HOTTIP is involved in the progression of CRC and may provide evidence for HOTTIP being a target for therapy of this disease.

Judes G, Rifaï K, Ngollo M, et al.
A bivalent role of TIP60 histone acetyl transferase in human cancer.
Epigenomics. 2015; 7(8):1351-63 [PubMed] Related Publications
Acetylation is a major modification that is required for gene regulation, genome maintenance and metabolism. A dysfunctional acetylation plays an important role in several diseases, including cancer. A group of enzymes-lysine acetyltransferases are responsible for this modification and act in regulation of transcription as cofactors and by acetylation of histones and other proteins. Tip60, a member of MYST family, is expressed ubiquitously and is the acetyltransferase catalytic subunit of human NuA4 complex. This HAT has a well-characterized involvement in many processes, such as cellular signaling, DNA damage repair, transcriptional and cellular cycle. Aberrant lysine acetyltransferase functions promote or suppress tumorigenesis in different cancers such as colon, breast and prostate tumors. Therefore, Tip60 might be a potential and important therapeutic target in the cancer treatment; new histone acetyl transferase inhibitors were identified and are more selective inhibitors of Tip60.

Sunde L, Lund H, J Sebire N, et al.
Paternal Hemizygosity in 11p15 in Mole-like Conceptuses: Two Case Reports.
Medicine (Baltimore). 2015; 94(44):e1776 [PubMed] Free Access to Full Article Related Publications
Hydatidiform mole is an abnormal human pregnancy characterized by the fetus being absent or nonviable, and the chorionic villi being vesicular and with trophoblastic hyperplasia. Most often, the mole phenotype is seen in conceptuses with an excess of paternally inherited genome set(s) relative to maternally inherited genome set(s), suggesting that the phenotype is caused by an excess of genome with a paternal imprinting pattern. However, it is unknown if correct parental origin of every imprinted gene is crucial for normal early differentiation or if abnormal parental imprinting of only one, or some, gene(s) can cause the mole phenotype.Two conceptuses included in the Danish Mole Project stood out since they presented with vesicular chorionic villi and without signs of fetal differentiation, and had apparently biparental diploid genomes, and no mutations in NLRP7 or KHDC3L were detected in the mothers. These conceptuses were subjected to a centralized histopathological revision and their genetic complements were scrutinized using fluorescence in situ hybridization, and DNA-marker and array comparative genomic hybridization analyses. Both conceptuses showed dysmorphic chorionic villi with some similarities to hydatidiform moles; however, no definite florid trophoblast hyperplasia was observed. Both conceptuses showed paternal hemizygosity of 11pter-11p15.4, most likely in nonmosaic state.Our findings suggest that the product of one (or a few) maternally expressed gene(s) on the tip of chromosome 11 is necessary for normal early embryonic differentiation. However, since the present two cases did not exhibit all features of hydatidiform moles, it is likely that abnormal parental imprinting of genes in other regions contribute to the phenotype of a hydatidiform mole.

Pandey AK, Zhang Y, Zhang S, et al.
TIP60-miR-22 axis as a prognostic marker of breast cancer progression.
Oncotarget. 2015; 6(38):41290-306 [PubMed] Free Access to Full Article Related Publications
MicroRNAs (miRNAs) are 22- to 24-nucleotide, small, non-coding RNAs that bind to the 3'UTR of target genes to control gene expression. Consequently, their dysregulation contributes to many diseases, including diabetes and cancer. miR-22 is up-regulated in numerous metastatic cancers and recent studies have suggested a role for miR-22 in promoting stemness and metastasis. TIP60 is a lysine acetyl-transferase reported to be down-regulated in cancer but the molecular mechanism of this reduction is still unclear. In this study, we identify TIP60 as a target of miR-22. We show a negative correlation in the expression of TIP60 and miR-22 in breast cancer patients, and show that low levels of TIP60 and high levels of miR-22 are associated with poor overall survival. Furthermore, pathway analysis using high miR-22/low TIP60 and low miR-22/high TIP60 breast cancer patient datasets suggests association of TIP60/miR-22 with epithelial-mesenchymal transition (EMT), a key alteration in progression of cancer cells. We show that blocking endogenous miR-22 can restore TIP60 levels, which in turn decreases the migration and invasion capacity of metastatic breast cancer cell line. These results provide mechanistic insight into TIP60 regulation and evidence for the utility of the combination of TIP60 and miR-22 as prognostic indicator of breast cancer progression.

Takino T, Nakada M, Li Z, et al.
Tip60 regulates MT1-MMP transcription and invasion of glioblastoma cells through NF-κB pathway.
Clin Exp Metastasis. 2016; 33(1):45-52 [PubMed] Related Publications
A histone acetyltransferase Tat-interacting protein 60 kDa (Tip60) regulates the DNA damage response by acetylating histone and remodeling chromatin. In addition to histone acetyltransferase activity, Tip60 is known to regulate a variety of cellular functions, including gene expression, DNA damage response, cell migration and apoptosis. Lower expression of Tip60 is observed in lymphomas, melanomas, breast, colon, and lung cancer. It is widely accepted that Tip60 functions as a tumor suppressor. However, a role of Tip60 in gliomas still remains unclear. In this study, we investigated the role of Tip60 in the malignant behavior of human gliomas. By quantitative RT-PCR analysis using fresh human brain tumor tissues from 55 patients, we found that lower Tip60 expression and higher membrane-type 1 matrix metalloproteinase (MT1-MMP) expression are associated with advanced tumor grade in glioma tissues. Knockdown of Tip60 in glioblastoma cells promoted cell adhesion, spreading and MT1-MMP transcription and thereby invasion, which was suppressed by inhibition of MT1-MMP and nuclear factor-kappa B (NF-κB) activity. We demonstrate for the first time that tumor suppressor Tip60 down-regulates cell adhesion and MT1-MMP expression and thereby invasion of glioblastoma cells by suppressing NF-κB pathway.

Navin NE
The first five years of single-cell cancer genomics and beyond.
Genome Res. 2015; 25(10):1499-507 [PubMed] Free Access to Full Article Related Publications
Single-cell sequencing (SCS) is a powerful new tool for investigating evolution and diversity in cancer and understanding the role of rare cells in tumor progression. These methods have begun to unravel key questions in cancer biology that have been difficult to address with bulk tumor measurements. Over the past five years, there has been extraordinary progress in technological developments and research applications, but these efforts represent only the tip of the iceberg. In the coming years, SCS will greatly improve our understanding of invasion, metastasis, and therapy resistance during cancer progression. These tools will also have direct translational applications in the clinic, in areas such as early detection, noninvasive monitoring, and guiding targeted therapy. In this perspective, I discuss the progress that has been made and the myriad of unexplored applications that still lie ahead in cancer research and medicine.

Olsen RS, Andersson RE, Zar N, et al.
Prognostic significance of PLA2G4C gene polymorphism in patients with stage II colorectal cancer.
Acta Oncol. 2016; 55(4):474-9 [PubMed] Related Publications
BACKGROUND: Phospholipase A2 Group IV C (PLA2G4C) catalyzes the release of certain fatty acids from phospholipids and plays a role in a range of physiological functions, such as remodeling of cell membranes and the production of prostaglandins. Furthermore, it has been proposed that PLA2G4C plays an important role in breast cancer cell chemotaxis. This study aimed to investigate the effect of a single nucleotide polymorphism (SNP) rs1549637 (T>A) of the PLA2G4C gene on the prognosis of colorectal cancer (CRC).
MATERIAL AND METHODS: Whole blood DNA was extracted from 381 patients with CRC and 618 controls, and a TaqMan SNP genotyping assay was used to determine the distribution of the genotypes. Cancer-specific and disease-free survival was analyzed by Kaplan-Meier graphs and by uni- and multivariable Cox regression.
RESULTS: The cancer-specific survival differed between the genotypes (p = 0.019) and the carriers of the A allele were associated with the highest risk of CRC death, with a hazard ratio (HR) of 1.72 [95% confidence interval (CI) 1.17-2.53, p = 0.006] compared with homozygous carriers of the T allele. This increased mortality in the carriers with the allele A was especially marked in stage II with an HR of 3.84 (95% CI 1.51-9.78, p = 0.005).
CONCLUSION: The A allele in PLA2G4C SNP (rs1549637) is associated with a worse prognosis in patients with CRC, especially in stage II disease, and it could be a potential prognostic biomarker in the planning of individual adjuvant therapy in stage II patients.

Verma SP, Subbiah A, Jacob SE, Basu D
Chronic myeloid leukaemia with extreme thrombocytosis.
BMJ Case Rep. 2015; 2015 [PubMed] Related Publications
We report two cases of chronic myeloid leukaemia (CML) with extreme thrombocytosis. The first patient was a 65-year-old man who presented with prolonged history of upper abdominal discomfort, anorexia and two episodes of recent gum bleeds without fever or other bleeding manifestations. He was a chronic smoker with no other comorbidities. Examination revealed moderate hepatosplenomegaly. On investigation, he was found to have extreme thrombocytosis (3,500,000/mm(3)) and leucocytosis with moderate anaemia. In view of the leucocytosis, he was investigated for CML and found to be positive for BCR-ABL by reverse transcription PCR (RT-PCR). He received imatinib 400 mg/day and achieved complete haematological response at the end of 3 months. The second patient was a 7-year-old boy who presented with fever, cough and cold of 2-week duration. Examination revealed mild hepatomegaly with palpable spleen tip. Haemogram and peripheral smear revealed moderate leucocytosis with extreme thrombocytosis (2,800,000/mm(3)). On evaluation, he was found to be BCR-ABL positive and responded well to imatinib treatment. In both these cases, massive thrombocytosis was an unusual presentation of a well-known entity, namely, CML. This degree of thrombocytosis is usually seen only in essential thrombocytosis.

Gao XY, Li L, Wang XH, et al.
Inhibition of sphingosine-1-phosphate phosphatase 1 promotes cancer cells migration in gastric cancer: Clinical implications.
Oncol Rep. 2015; 34(4):1977-87 [PubMed] Related Publications
Sphingosine-1-phosphate (S1P) plays an important role in regulating many biological processes. Sphingosine-1-phosphate phosphatase 1 (SGPP1) can dephosphorylate S1P into sphingosine and tip the balance of sphingosine-S1P. Increased levels of sphingosine leads to a decrease in the ability of cell invasion as well as an increase in the ability of cell apoptosis. However, little is known regarding the effects of SGPP1 in gastric cancer. The present study examined the function of SGPP1 on gastric cancer cell lines as well as its clinical relevance in gastric cancer progression. Using immunohistochemistry and RT-qPCR techniques, the clinical significance of SGPP1 expression was analyzed in 288 paraffin-embedded gastric tissue specimens and 219 fresh gastric tissues, respectively. Transgenes encoding ribozymes to specifically target human SGPP1 (pEF-SGPP1) was constructed. Human gastric cancer cell lines (AGS and HGC27) were transfected with pEF-SGPP1 transgene and examined by functional analysis. SGPP1 was downregulated in gastric cancer tissues, compared with adjacent normal gastric tissues (p=0.034). SGPP1 mRNA levels in gastric cancer tissues were significantly decreased when compared with their adjacent non-cancerous tissues (p<0.001). Weakly expressed SGPP1 was positively correlated with the lymph node metastasis (p=0.005) and distant metastasis (p=0.031). Kaplan-Meier survival curves revealed that patients with SGPP1 positive expression had a significant increase in overall survival (OS) (p=0.034) and progression-free survival (PFS) (p=0.041). Multivariate analysis indicated the expression of SGPP1 was an independent prognostic factor in gastric cancer patients (p=0.041). In vitro experiments showed that knockdown of SGPP1 resulted in an increase in the invasion (2-fold) and migration (5-fold) of AGS and HGC27. The two gastric cancer cells transfected with pEF-SGPP1 exhibited a slower rate of growth with less adhesion. Thus, our findings provided evidence that SGPP1 may serve as a prognostic biomarker for patients with advanced gastric cancers.

Hua S, Vignarajan S, Yao M, et al.
AKT and cytosolic phospholipase A2α form a positive loop in prostate cancer cells.
Curr Cancer Drug Targets. 2015; 15(9):781-91 [PubMed] Related Publications
Aberrant increase in protein kinase B (AKT) phosphorylation (pAKT), due to a gain-of-function mutation of phosphatidylinositol-3-kinase (PI3K) or loss-of-function mutation or deletion of phosphatase and tensin homolog (PTEN), is a common alteration in prostate cancer and associated with poor prognosis. Cytosolic phospholipase A2α (cPLA2α) is a lipid modifying enzyme by catalyzing the hydrolysis of arachidonic acid from membrane phospholipid. The released arachidonic acid and its metabolites contribute to survival and proliferation of prostate cancer cells. In this mini-review, we summarize the relationship between pAKT and cPLA2α in prostate cancer cells. There was a concordant increase in pAKT and cPLA2α levels in prostate tissue of prostate epithelial-specific PTEN-knockout mice compared to PTEN-wild type mice. Restoration of PTEN expression or inhibition of PI3K action decreased cPLA2α expression in PTEN-mutated or deleted prostate cancer cells. An increase in AKT phosphorylation elevated, whereas inhibition of AKT phosphorylation diminished, cPLA2α protein levels. pAKT had no influence on cPLA2α expression at mRNA levels but stabilized cPLA2α at protein levels by protecting it from degradation. Conversely, an induction of cPLA2α expression led to an increase in pAKT levels in PTEN-mutated or deleted prostate cancer cells, while silencing of cPLA2α expression or pharmacological blocking cPLA2α action decreased pAKT levels. The diminishment of pAKT by either genetic silencing or pharmacological blocking of cPLA2α was mitigated by the addition of arachidonic acid. The stimulatory effect of arachidonic acid on pAKT levels was lessened by inhibiting the production of arachidonic acid metabolites. These studies have revealed a link between oncogenic pathway and lipid metabolism and provided potential molecular targets for treating prostate cancer.

Stewart A, Maity B, Fisher RA
Two for the Price of One: G Protein-Dependent and -Independent Functions of RGS6 In Vivo.
Prog Mol Biol Transl Sci. 2015; 133:123-51 [PubMed] Related Publications
Regulator of G protein signaling 6 (RGS6) is unique among the members of the RGS protein family as it remains the only protein with the demonstrated capacity to control G protein-dependent and -independent signaling cascades in vivo. RGS6 inhibits signaling mediated by γ-aminobutyric acid B receptors, serotonin 1A receptors, μ opioid receptors, and muscarinic acetylcholine 2 receptors. RGS6 deletion triggers distinct behavioral phenotypes resulting from potentiated signaling by these G protein-coupled receptors namely ataxia, a reduction in anxiety and depression, enhanced analgesia, and increased parasympathetic tone, respectively. In addition, RGS6 possesses potent proapoptotic and growth suppressive actions. In heart, RGS6-dependent reactive oxygen species (ROS) production promotes doxorubicin (Dox)-induced cardiomyopathy, while in cancer cells RGS6/ROS signaling is necessary for activation of the ataxia telangiectasia mutated/p53/apoptosis pathway required for the chemotherapeutic efficacy of Dox. Further, by facilitating Tip60 (trans-acting regulator protein of HIV type 1-interacting protein 60 kDa)-dependent DNA methyltransferase 1 degradation, RGS6 suppresses cellular transformation in response to oncogenic Ras. The culmination of these G protein-independent actions results in potent tumor suppressor actions of RGS6 in the murine mammary epithelium. This work summarizes evidence from human genetic studies and model animals implicating RGS6 in normal physiology, disease, and the pharmacological actions of multiple drugs. Though efforts by multiple laboratories have contributed to the ever-growing RGS6 oeuvre, the pleiotropic nature of this gene will likely lead to additional work detailing the importance of RGS6 in neuropsychiatric disorders, cardiovascular disease, and cancer.

Li J, Li O, Kan M, et al.
Berberine induces apoptosis by suppressing the arachidonic acid metabolic pathway in hepatocellular carcinoma.
Mol Med Rep. 2015; 12(3):4572-7 [PubMed] Related Publications
Berberine (BBR) has been suggested as a potential candidate anticancer agent due to its high anticancer activity and multiple mechanisms. In the present study, the inhibitory effect of BBR on hepatocellular carcinoma (HCC) via the suppression of the arachidonic acid (AA) metabolic pathway was investigated. BBR was demonstrated to reduce the viabilities of H22, HepG2 and Bel‑7404 cells, in a dose‑ and time‑dependent manner, and increase the number of apoptotic cells. BBR induced the translocation of apoptosis‑inducing factor between the mitochondria and the nucleus, and had no effects on the protein expression levels of caspase‑3 or ‑9. In addition, BBR significantly suppressed the protein expression levels of cytosolic phospholipase A2 (cPLA2) and cyclooxygenase (COX)‑2 and elevated the content ratio of AA to prostaglandin E2 (PGE2). Furthermore, BBR reduced the volume and weight of tumors in a H22 transplanted tumor model in mice. The results of the present study demonstrated that elevation in the ratio of AA to PGE2 via suppression of the protein expression of cPLA2 and COX‑2 in the AA metabolic pathway is involved in the inhibitory effect of BBR in HCC.

Lee HL, Park MH, Son DJ, et al.
Anti-cancer effect of snake venom toxin through down regulation of AP-1 mediated PRDX6 expression.
Oncotarget. 2015; 6(26):22139-51 [PubMed] Free Access to Full Article Related Publications
Snake venom toxin (SVT) from Vipera lebetina turanica contains a mixture of different enzymes and proteins. Peroxiredoxin 6 (PRDX6) is known to be a stimulator of lung cancer cell growth. PRDX6 is a member of peroxidases, and has calcium-independent phospholipase A2 (iPLA2) activities. PRDX6 has an AP-1 binding site in its promoter region of the gene. Since AP-1 is implicated in tumor growth and PRDX6 expression, in the present study, we investigated whether SVT inhibits PRDX6, thereby preventing human lung cancer cell growth (A549 and NCI-H460) through inactivation of AP-1. A docking model study and pull down assay showed that SVT completely fits on the basic leucine zipper (bZIP) region of c-Fos of AP-1. SVT (0-10 μg/ml) inhibited lung cancer cell growth in a concentration dependent manner through induction of apoptotic cell death accompanied by induction of cleaved caspase-3, -8, -9, Bax, p21 and p53, but decreased cIAP and Bcl2 expression via inactivation of AP-1. In an xenograft in vivo model, SVT (0.5 mg/kg and 1 mg/kg) also inhibited tumor growth accompanied with the reduction of PRDX6 expression, but increased expression of proapoptotic proteins. These data indicate that SVT inhibits tumor growth via inhibition of PRDX6 activity through interaction with its transcription factor AP-1.

Zhang H, Zhao L, Wang YX, et al.
Long non-coding RNA HOTTIP is correlated with progression and prognosis in tongue squamous cell carcinoma.
Tumour Biol. 2015; 36(11):8805-9 [PubMed] Related Publications
Long non-coding RNAs (lncRNAs) have been demonstrated to be a critical role in cancer progression and prognosis. However, little is known about the pathological role of lncRNA HOXA transcript at the distal tip (HOTTIP) in tongue squamous cell carcinoma (TSCC) patients. The aim of this study is to measure the expression of lncRNA HOTTIP in TSCC patients and to explore the clinical significance of the lncRNA HOTTIP. The expression of lncRNA HOTTIP was measured in 86 TSCC tissues and 14 adjacent non-malignant tissues using qRT-PCR. In our study, results indicated that lncRNA HOTTIP was highly expressed in TSCC compared with adjacent non-malignant tissues (P < 0.001) and positively correlated with T stage (T1-2 vs. T3-4, P = 0.023), clinical stage (I-II stages vs. III-IV stages, P = 0.018), and distant metastasis (absent vs. present, P = 0.031) in TSCC patients. Furthermore, we also found that lncRNA HOTTIP overexpression was an unfavorable prognostic factor in TSCC patients (P < 0.001), regardless of T stage, distant metastasis, and clinical stage. Finally, overexpression of lncRNA HOTTIP was supposed to be an independent poor prognostic factor for TSCC patients through multivariate analysis (P = 0.023). In conclusion, increased lncRNA HOTTIP expression may be serve as an unfavorable prognosis predictor for TSCC patients. Nevertheless, further investigation with a larger sample size is needed to support our results.

Li Q, Sun H, Shu Y, et al.
hMOF (human males absent on the first), an oncogenic protein of human oral tongue squamous cell carcinoma, targeting EZH2 (enhancer of zeste homolog 2).
Cell Prolif. 2015; 48(4):436-42 [PubMed] Related Publications
OBJECTIVES: MOF (males absent on the first) is a histone acetyltransferase belonging to the MYST (MOZ, Ybf2/Sas3, Sas2 and TIP60) family. In mammals, MOF plays critical roles in transcription activation by acetylating histone H4 at K16. Human MOF (hMOF) essentially participates in behaviour of several human cancers. However, its role in human oral tongue squamous cell carcinoma (OTSCC) remains elusive, but we propose that hMOF regulates OTSCC cell population growth.
MATERIALS AND METHODS: Real time PCR and western blot analysis were applied, and it was found that hMOF level was up-regulated in human OTSCC. High hMOF expression predicted poor overall and disease-free survival. hMOF knockdown attenuated OTSCC cell growth and transformation.
RESULTS: EZH2 (enhancer of zeste homolog 2) was up-regulated in human OTSCC tissues and its level positively correlated with level of hMOF. hMOF knockdown inhibited EZH2 expression by reducing its promoter activity. Moreover, we have demonstrated that EZH2 was critically essential for function of hMOF in human OTSCC.
CONCLUSIONS: Human males absent on the first regulated OSTCC growth through EZH2, thus EZH2 may serve as a candidate for anti-OTSCC therapy.

Shen H, An M, Zou X, et al.
Evaluation of the accuracy of protein quantification using isotope TMPP-labeled peptides.
Proteomics. 2015; 15(17):2903-9 [PubMed] Related Publications
N-succinimidyloxycarbonylmethyl tris(2,4,6-trimethoxyphenyl) phosphonium bromide (TMPP-Ac-OSu) reacts rapidly, mildly, and specifically with the N-terminals of proteins and peptides. Thus, it can be developed as an ideal isotope-coded tag to be used in quantitative proteomics. Here, we present a strategy for light and heavy TMPP-based quantitative proteomic analysis, in which peptides in a mixture can be quantified using an on-tip TMPP derivatization approach. To demonstrate the accuracy of this strategy, light and heavy TMPP-labeled peptides were combined at different ratios and subsequently analyzed by LC-MS/MS. The MS spectra and scatter plots show that peptide and protein ratios were both consistent with the mixed ratios. We observed a linear correlation between protein ratios and the predicted ratios. In comparison with SILAC method, the TMPP labeling method produced similarly accurate quantitative results with low CVs. In conclusion, our results suggest that this isotope-coded TMPP method achieved accurate quantification and compatibility with IEF-based separation. With the inherent advantages of TMPP derivatization, we believe that it holds great promise for future applications in quantitative proteomics analysis.

Cheng Y, Jutooru I, Chadalapaka G, et al.
The long non-coding RNA HOTTIP enhances pancreatic cancer cell proliferation, survival and migration.
Oncotarget. 2015; 6(13):10840-52 [PubMed] Free Access to Full Article Related Publications
HOTTIP is a long non-coding RNA (lncRNA) transcribed from the 5' tip of the HOXA locus and is associated with the polycomb repressor complex 2 (PRC2) and WD repeat containing protein 5 (WDR5)/mixed lineage leukemia 1 (MLL1) chromatin modifying complexes. HOTTIP is expressed in pancreatic cancer cell lines and knockdown of HOTTIP by RNA interference (siHOTTIP) in Panc1 pancreatic cancer cells decreased proliferation, induced apoptosis and decreased migration. In Panc1 cells transfected with siHOTTIP, there was a decrease in expression of 757 genes and increased expression of 514 genes, and a limited gene analysis indicated that HOTTIP regulation of genes is complex. For example, Aurora kinase A, an important regulator of cell growth, is coregulated by MLL and not WDR5 and, in contrast to previous studies in liver cancer cells, HOTTIP does not regulate HOXA13 but plays a role in regulation of several other HOX genes including HOXA10, HOXB2, HOXA11, HOXA9 and HOXA1. Although HOTTIP and the HOX-associated lncRNA HOTAIR have similar pro-oncogenic functions, they regulate strikingly different sets of genes in Panc1 cells and in pancreatic tumors.

Li Z, Zhao X, Zhou Y, et al.
The long non-coding RNA HOTTIP promotes progression and gemcitabine resistance by regulating HOXA13 in pancreatic cancer.
J Transl Med. 2015; 13:84 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: The human genome encodes many long non-coding RNAs (lncRNAs). However, their biological functions, molecular mechanisms, and the prognostic value associated with pancreatic ductal adenocarcinoma (PDAC) remain to be elucidated. Here, we identify a fundamental role for the lncRNA HOXA transcript at the distal tip (HOTTIP) in the progression and chemoresistance of PDAC.
METHODS: High-throughput microarrays were performed to detect the expression profiles of lncRNAs and messenger RNAs in eight human PDAC tissues and four pancreatic tissues. Quantitative real-time PCR was used to determine the levels of HOTTIP and HOXA13 transcripts in PDAC cell lines and 90 PDAC samples from patients. HPDE6 cells (immortalized human pancreatic ductal epithelial cells) and corresponding adjacent non-neoplastic tissues were used as controls, respectively. The functions of HOTTIP and HOXA13 in cell proliferation, invasion, and epithelial-mesenchymal transition were evaluated by targeted knockdown in vitro. CCK-8 assays, colony formation assays, and xenografts in nude mice were used to investigate whether targeted silencing of HOTTIP could sensitize pancreatic cancer cells to gemcitabine. Immunohistochemistry was performed to investigate the relationship between HOXA13 expression and patient outcome.
RESULTS: Microarray analyses revealed that HOTTIP was one of the most significantly upregulated lncRNAs in PDAC tissues compared with pancreatic tissues. Quantitative PCR further verified that HOTTIP levels were increased in PDAC cell lines and patient samples compared with controls. Functionally, HOTTIP silencing resulted in proliferation arrest by altering cell-cycle progression, and impaired cell invasion by inhibiting epithelial-mesenchymal transition in pancreatic cancer. Additionally, inhibition of HOTTIP potentiated the antitumor effects of gemcitabine in vitro and in vivo. Furthermore, knockdown of HOXA13 by RNA interference (siHOXA13) revealed that HOTTIP promoted PDAC cell proliferation, invasion, and chemoresistance, at least partly through regulating HOXA13. Immunohistochemistry results revealed that higher HOXA13 expression was correlated with lymph node metastasis, poor histological differentiation, and decreased overall survival in PDAC patients.
CONCLUSIONS: As a crucial tumor promoter, HOTTIP promotes cell proliferation, invasion, and chemoresistance by modulating HOXA13. Therefore, the HOTTIP/HOXA13 axis is a potential therapeutic target and molecular biomarker for PDAC.

Bayram Y, Aydin H, Gambin T, et al.
Exome sequencing identifies a homozygous C5orf42 variant in a Turkish kindred with oral-facial-digital syndrome type VI.
Am J Med Genet A. 2015; 167A(9):2132-7 [PubMed] Free Access to Full Article Related Publications
Oral-facial-digital syndrome type VI (OFDVI) is a rare ciliopathy in the spectrum of Joubert syndrome (JS) and distinguished from other oral-facial-digital syndromes by metacarpal abnormalities with central polydactyly and by a molar tooth sign on cranial MRI. Additional characteristic features include short stature, micrognathia, posteriorly rotated low-set ears, hypertelorism, epicanthal folds, broad nasal tip, tongue hamartoma, upper lip notch, intraoral frenula, cleft lip/palate, and renal anomalies. Recently, novel mutations in C5orf42 were identified in 9 out of 11 OFDVI families. In a subsequent study C5orf42 was found to be mutated in only 2 out of 17 OFDVI probands while 28 patients with a pure JS phenotype also had pathogenic mutations of C5orf42. We report on two affected cousins diagnosed with OFDVI who were born from first degree cousin marriages. Whole exome sequencing (WES) identified a homozygous predicted damaging missense mutation (c.4034A > G; p.Gln1345Arg) in the C5orf42 gene. Our data contribute to the evidence that C5orf42 is one of the causative genes for OFDVI.

Liu C, Ding H, Li X, et al.
A DNA/HDAC dual-targeting drug CY190602 with significantly enhanced anticancer potency.
EMBO Mol Med. 2015; 7(4):438-49 [PubMed] Free Access to Full Article Related Publications
Genotoxic drugs constitute a major treatment modality for human cancers; however, cancer cells' intrinsic DNA repair capability often increases the threshold of lethality and renders these drugs ineffective. The emerging roles of HDACs in DNA repair provide new opportunities for improving traditional genotoxic drugs. Here, we report the development and characterization of CY190602, a novel bendamustine-derived drug with significantly enhanced anticancer potency. We show that CY190602's enhanced potency can be attributed to its newly gained ability to inhibit HDACs. Using this novel DNA/HDAC dual-targeting drug as a tool, we further explored HDAC's role in DNA repair. We found that HDAC activities are essential for the expression of several genes involved in DNA synthesis and repair, including TYMS, Tip60, CBP, EP300, and MSL1. Importantly, CY190602, the first-in-class example of such DNA/HDAC dual-targeting drugs, exhibited significantly enhanced anticancer activity in vitro and in vivo. These findings provide rationales for incorporating HDAC inhibitory moieties into genotoxic drugs, so as to overcome the repair capacity of cancer cells. Systematic development of similar DNA/HDAC dual-targeting drugs may represent a novel opportunity for improving cancer therapy.

Foda AA, Mohammad MA, Abdel-Aziz A, El-Hawary AK
Relation of glypican-3 and E-cadherin expressions to clinicopathological features and prognosis of mucinous and non-mucinous colorectal adenocarcinoma.
Tumour Biol. 2015; 36(6):4671-9 [PubMed] Related Publications
Glypican-3 (GPC3) is a member of the membrane-bound heparin sulfate proteoglycans. E-cadherin is an adhesive receptor that is believed to act as a tumor suppressor gene. Many studies had investigated E-cadherin expressions in colorectal carcinoma (CRC) while only one study had investigated GPC3 expression in CRC. This study aims to investigate expression of GCP3 and E-cadherin in colorectal mucinous carcinoma (MA) and non-mucinous adenocarcinoma (NMA) using manual tissue microarray technique. Tumor tissue specimens are collected from 75 cases of MC and 75 cases of NMA who underwent radical surgery from Jan 2007 to Jan 2012 at the Gastroenterology Centre, Mansoura University, Egypt. Their clinicopathological parameters and survival data were revised and analyzed using established statistical methodologies. High-density manual tissue microarrays were constructed using modified mechanical pencil tip technique and immunohistochemistry for GPC3 and E-cadherin was done. NMA showed higher expression of GPC3 than MA with no statistically significant relation. NMA showed a significantly higher E-cadherin expression than MA. GPC3 and E-cadherin positivity rates were significantly interrelated in NMA, but not in MA, group. In NMA group, there was no significant relation between either GPC3 or E-cadherin expression and the clinicopathological features. In a univariate analysis, neither GPC3 nor E-cadherin expression showed a significant impact on disease-free survival (DFS) or overall survival (OS). GPC3 and E-cadherin expressions are not independent prognostic factors in CRC. However, expressions of both are significantly interrelated in NMA patients, suggesting an excellent interplay between both, in contrast to MA. Further molecular studies are needed to further explore the relationship between GCP3 and E-cadherin in colorectal carcinogenesis.

Efroni I, Ip PL, Nawy T, et al.
Quantification of cell identity from single-cell gene expression profiles.
Genome Biol. 2015; 16:9 [PubMed] Free Access to Full Article Related Publications
The definition of cell identity is a central problem in biology. While single-cell RNA-seq provides a wealth of information regarding cell states, better methods are needed to map their identity, especially during developmental transitions. Here, we use repositories of cell type-specific transcriptomes to quantify identities from single-cell RNA-seq profiles, accurately classifying cells from Arabidopsis root tips and human glioblastoma tumors. We apply our approach to single cells captured from regenerating roots following tip excision. Our technique exposes a previously uncharacterized transient collapse of identity distant from the injury site, demonstrating the biological relevance of a quantitative cell identity index.

Uehara T, Kage-Nakadai E, Yoshina S, et al.
The Tumor Suppressor BCL7B Functions in the Wnt Signaling Pathway.
PLoS Genet. 2015; 11(1):e1004921 [PubMed] Free Access to Full Article Related Publications
Human BCL7 gene family consists of BCL7A, BCL7B, and BCL7C. A number of clinical studies have reported that BCL7 family is involved in cancer incidence, progression, and development. Among them, BCL7B, located on chromosome 7q11.23, is one of the deleted genes in patients with Williams-Beuren syndrome. Although several studies have suggested that malignant diseases occurring in patients with Williams-Beuren syndrome are associated with aberrations in BCL7B, little is known regarding the function of this gene at the cellular level. In this study, we focused on bcl-7, which is the only homolog of BCL7 gene family in Caenorhabditis elegans, and analyzed bcl-7 deletion mutants. As a result, we found that bcl-7 is required for the asymmetric differentiation of epithelial seam cells, which have self-renewal properties as stem cells and divide asymmetrically through the WNT pathway. Distal tip cell development, which is regulated by the WNT pathway in Caenorhabditis elegans, was also affected in bcl-7-knockout mutants. Interestingly, bcl-7 mutants exhibited nuclear enlargement, reminiscent of the anaplastic features of malignant cells. Furthermore, in KATOIII human gastric cancer cells, BCL7B knockdown induced nuclear enlargement, promoted the multinuclei phenotype and suppressed cell death. In addition, this study showed that BCL7B negatively regulates the Wnt-signaling pathway and positively regulates the apoptotic pathway. Taken together, our data indicate that BCL7B/BCL-7 has some roles in maintaining the structure of nuclei and is involved in the modulation of multiple pathways, including Wnt and apoptosis. This study may implicate a risk of malignancies with BCL7B-deficiency, such as Williams-Beuren syndrome.

Biswas NK, Das S, Maitra A, et al.
Somatic mutations in arachidonic acid metabolism pathway genes enhance oral cancer post-treatment disease-free survival.
Nat Commun. 2014; 5:5835 [PubMed] Related Publications
The arachidonic acid metabolism (AAM) pathway promotes tumour progression. Chemical inhibitors of AAM pathway prolong post-treatment survival of cancer patients. Here we test whether non-synonymous somatic mutations in genes of this pathway, acting as natural inhibitors, increase post-treatment survival. We identify loss-of-function somatic mutations in 15 (18%) of 84 treatment-naïve oral cancer patients by whole-exome sequencing, which we map to genes of AAM pathway. Patients (n = 53) who survived ≥ 12 months after surgery without recurrence have significantly (P = 0.007) higher proportion (26% versus 3%) of mutations than those who did not (n = 31). Patients with mutations have a significantly (P = 0.003) longer median disease-free survival (24 months) than those without (13 months). Compared with the presence of a mutation, absence of any mutation increases the hazard ratio for death (11.3) significantly (P = 0.018). The inferences are strengthened when we pool our data with The Cancer Genome Atlas (TCGA) data. In patients with AAM pathway mutations, some downstream pathways, such as the PI3K-Akt pathway, are downregulated.

Shi J, Cao J, Zhou BP
Twist-BRD4 complex: potential drug target for basal-like breast cancer.
Curr Pharm Des. 2015; 21(10):1256-61 [PubMed] Related Publications
As an important basic helix-loop-helix (bHLH) transcription factor, Twist associates with several physiological processes such as mesodermal development, and pathological processes such as Saethre-Chotzen syndrome. During cancer progression, Twist induces epithelial-mesenchymal transition (EMT), potentiating cancer cell invasion and metastasis. Although many studies have revealed its multiple biological roles, it remained unclear how Twist transcriptionally activates targeted genes. Recently we discovered tip60-mediated Twist di-acetylation in the ''histone H4-mimic'' GK-X-GK motif. The di-acetylated Twist recruits BRD4 and related transcriptional components to super-enhancer of its targeted genes during progression of basal-like breast cancer (BLBC). Here, we review this new advance of regulation and functional mechanism of Twist.

Eriksson CJ
Genetic-epidemiological evidence for the role of acetaldehyde in cancers related to alcohol drinking.
Adv Exp Med Biol. 2015; 815:41-58 [PubMed] Related Publications
Alcohol drinking increases the risk for a number of cancers. Currently, the highest risk (Group 1) concerns oral cavity, pharynx, larynx, esophagus, liver, colorectum, and female breast, as assessed by the International Agency for Research on Cancer (IARC). Alcohol and other beverage constituents, their metabolic effects, and alcohol-related unhealthy lifestyles have been suggested as etiological factors. The aim of the present survey is to evaluate the carcinogenic role of acetaldehyde in alcohol-related cancers, with special emphasis on the genetic-epidemiological evidence. Acetaldehyde, as a constituent of alcoholic beverages, and microbial and endogenous alcohol oxidation well explain why alcohol-related cancers primarily occur in the digestive tracts and other tissues with active alcohol and acetaldehyde metabolism. Genetic-epidemiological research has brought compelling evidence for the causality of acetaldehyde in alcohol-related cancers. Thus, IARC recently categorized alcohol-drinking-related acetaldehyde to Group 1 for head and neck and esophageal cancers. This is probably just the tip of the iceberg, since more recent epidemiological studies have also shown significant positive associations between the aldehyde dehydrogenase ALDH2 (rs671)*2 allele (encoding inactive enzyme causing high acetaldehyde elevations) and gastric, colorectal, lung, and hepatocellular cancers. However, a number of the current studies lack the appropriate matching or stratification of alcohol drinking in the case-control comparisons, which has led to erroneous interpretations of the data. Future studies should consider these aspects more thoroughly. The polymorphism phenotypes (flushing and nausea) may provide valuable tools for future successful health education in the prevention of alcohol-drinking-related cancers.

Disclaimer: This site is for educational purposes only; it can not be used in diagnosis or treatment.

Cite this page: Cotterill SJ. KAT5, Cancer Genetics Web: http://www.cancer-genetics.org/KAT5.htm Accessed:

Creative Commons License
This page in Cancer Genetics Web by Simon Cotterill is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
Note: content of abstracts copyright of respective publishers - seek permission where appropriate.

 [Home]    Page last revised: 09 March, 2017     Cancer Genetics Web, Established 1999