Expression Of ATAD2 Research Articles

MiR-372 down-regulates the oncogene ATAD2 to influence hepatocellular carcinoma proliferation and metastasis

BackgroundATAD2 is associated with many cellular processes, such as cell growth, migration and invasion. However, no studies have been conducted on the molecular biological function of the ATAD2 gene in hepatocellular carcinoma (HCC).MethodsThe protein and mRNA level expression of ATAD2 was examined in tissues and cell lines. Prognostic significance was analyzed by the Kaplan-Meier survival method and Cox regression. ATAD2 knockdown was used to analyze cell proliferation and invasion. The upstream and downstream of ATAD2 was analyzed by RT2 Profiler™ PCR array and luciferasex fluorescence system.ResultsATAD2 was highly expressed in liver cancer samples and correlated with poor survival. High ATAD2 expression was positively correlated with metastasis (P = 0.005) and was an independent prognostic factor in HCC (P = 0.001). ATAD2 depletion by RNA interference reduced their capacity for invasion and proliferation and led to a G1 phase arrest in vitro. Further study revealed that miR-372 was an upstream target of ATAD2 as miR-372 was bound directly to its 3′ untranslated region (3′ UTR). In addition, ATAD2 knockdown was found to extremely up-regulate APC expression and down-regulate CTNNA1 at the mRNA level.ConclusionsThe findings demonstrated that miR-372 suppressed the expression of ATAD2, which was highly expressed in HCC and exerted a proto-oncogene effect in hepatic carcinogenesis. In conclusion, ATAD2 may promote HCC progression.

Chemical synthesis of the ATAD2 bromodomain

Due to the emerging importance of the bromodomain binding region in the study of epigenetic effectors and the vast implications for a wide variety of human disease, the bromodomain region of human ATPase family AAA+ (ATPases associated with diverse cellular activities) domain-containing protein 2 (ATAD2) was targeted for chemical synthesis. The ATAD2 bromodomain (130 aa) was divided into five strategic fragments to be assembled using native chemical ligation with a focus on maximal convergency and efficiency. The fragments were assembled with one cysteine and three thioleucine ligations, unveiling the native alanine and leucine amino acids at the ligation points following metal-free dethiylation. Synthetic highlights of the study are a photolabile dimethoxynitrobenzyl-protected glutamic acid side chain used to impede hydrolysis of the C-terminal Glu-thioester, a thiazolidine-protected thioleucine, and an efficient assembly of three fragments in a single reaction vessel with dual-mode kinetic-standard chemical ligation. With a focus on material throughput and convergency, the five peptide fragments were assembled into the native ATAD2 bromodomain region with a total of three HPLC events in 8% overall yield from the fragments.

Integrated Genomic Analysis of the 8q24 Amplification in Endometrial Cancers Identifies ATAD2 as Essential to MYC-Dependent Cancers

Chromosome 8q24 is the most commonly amplified region across multiple cancer types, and the typical length of the amplification suggests that it may target additional genes to MYC. To explore the roles of the genes most frequently included in 8q24 amplifications, we analyzed the relation between copy number alterations and gene expression in three sets of endometrial cancers (N = 252); and in glioblastoma, ovarian, and breast cancers profiled by TCGA. Among the genes neighbouring MYC, expression of the bromodomain-containing gene ATAD2 was the most associated with amplification. Bromodomain-containing genes have been implicated as mediators of MYC transcriptional function, and indeed ATAD2 expression was more closely associated with expression of genes known to be upregulated by MYC than was MYC itself. Amplifications of 8q24, expression of genes downstream from MYC, and overexpression of ATAD2 predicted poor outcome and increased from primary to metastatic lesions. Knockdown of ATAD2 and MYC in seven endometrial and 21 breast cancer cell lines demonstrated that cell lines that were dependent on MYC also depended upon ATAD2. These same cell lines were also the most sensitive to the histone deacetylase (HDAC) inhibitor Trichostatin-A, consistent with prior studies identifying bromodomain-containing proteins as targets of inhibition by HDAC inhibitors. Our data indicate high ATAD2 expression is a marker of aggressive endometrial cancers, and suggest specific inhibitors of ATAD2 may have therapeutic utility in these and other MYC-dependent cancers.

Abstract 5267: Relationship between gene and tumor marker expression in primary breast carcinoma and lymph node metastases of the same patient

Abstract Purpose: Our goal is to develop genomics-based tests of primary breast carcinoma for assessing risk of recurrence by comparing gene and tumor marker expression of primary lesions with those of lymph node and distant metastases. Using microarray analyses from our studies and other reports, 32 candidate genes were selected from carcinoma and stromal cells, whose expression appears related to clinical outcome of breast cancer (Andres et al., Cancer Res 69(Suppl): 403s-404s, 2009). Expression of candidate genes was evaluated with estrogen (ER) and progestin receptor (PR) protein levels to ascertain their relationship during lymph node invasion. Procedures: ER and PR levels were determined by either ligand binding or enzyme immunoassay. RNA was isolated from tissue sections of de-identified frozen biopsies of invasive ductal carcinoma using the RNeasy® Mini kit (Qiagen) and analyzed for quality and quantity (Agilent Bioanalyzer). cDNA for qPCR measurements was prepared in Tris-HCl buffer with KCl, MgCl2, DTT (Invitrogen), dNTPs (Invitrogen), RNasin® (Promega) and Superscript® RT III (Invitrogen). qPCR reactions were performed using Power Sybr® Green PCR Master Mix (Applied Biosystems), forward/reverse primers and cDNA obtained from the reverse transcription reaction. Relative gene expression was calculated by the ddCt method, using β-actin as a reference and Universal Human Reference RNA (Stratagene) as a calibrator. Results: Although ER and PR protein levels varied between the primary and lymph node metastasis, no patient with an ER- or PR- primary exhibited a positive ER/PR result in the metastasis. Only 3 patients with an ER+ or PR+ primary exhibited a loss of receptor expression in the lymph node metastasis. Expression of 15 of 32 genes (EVL, GABRP, TRIM29, IL6ST, RABEP1, SLC39A6, FUT8, PFKP, XBP1, MCM6, YBX1, LRBA, GATA3, MAPRE2, CKS2) was discordant in most primary lesion-lymph node metastasis pairs. However, expression of NAT1, ESR1, ST8SIA1, TBC1D9, CENPA, PLK1, ATAD2, PTP4A2, CX3CL1 GMPS and SLC43A3 exhibited concordance in the majority of primary-metastasis pairs. Only 3 patients exhibited differences in expression levels of SCUBE2, TPBG, TCEAL1, DSC2, MELK and BUB1 in primary-nodal metastasis pairs. Conclusions: To ascertain genomic changes in primary breast carcinomas and lymph node metastases, we compared levels of 32 candidate genes whose expression appears related to clinical outcome of breast cancer. Seldom was gene expression in the metastasis greater than that of the primary. Gene expression and biological activities of their protein products are used to classify subsets of primary breast cancers according to metastatic spread. These results serve as the foundation for developing a genomics-based test to predict risk of breast cancer recurrence. Supported in part by grants from Phi Beta Psi Charity Trust and a CTSP Grant from the Commonwealth of Kentucky. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 5267. doi:10.1158/1538-7445.AM2011-5267

Prognostic significance of drug-regulated genes in high-grade osteosarcoma

About 25–45% of patients with high-grade osteosarcoma poorly respond to chemotherapy with an increased risk of relapse and the development of metastasis. Therefore, the aim of this study was the evaluation of the prognostic value of eight previously identified drug-regulated candidate genes on osteosarcoma therapy outcome. Gene expression of 8 candidate genes was analyzed in 35 formalin-fixed, paraffin-embedded, laser-microdissected osteosarcoma biopsies. The prognostic value of these genes was evaluated by the correlation of gene expression with therapy outcome, overall survival and event-free survival in univariate and multivariate analysis. Upon univariate analysis, the expression of MALAT-1, IMPDH2, FTL and RHOA significantly correlated with response to chemotherapy. Expression of all four genes was increased in the poor responder group. Upon multivariate analysis, IMPDH2 maintained its independent prognostic value (P=0.025). Concerning the overall survival of the patients, we observed a significant association with the expression of FTL, PHB, ATAD2, ACTN1 and RRM2 as well as lactate dehydrogenase serum levels. In the subgroups of patients with high expression of these genes and those with elevated lactate dehydrogenase levels, the mean overall survival was decreased 1.7-, 1.9-, 2.2-, 2.4-, 1.5- and 4.5-fold, respectively. Except RRM2, all genes and lactate dehydrogenase serum levels remained significant in the multivariate analysis. In addition, the event-free survival was significantly decreased in the subgroups of patients with high FTL, ATAD2 and IMPDH2 expression (1.8-, 6.3- and 2.4-fold, respectively). These data demonstrate that among the identified genes are valuable markers for the prediction of osteosarcoma therapy outcome. Especially IMPDH2 and FTL are promising candidates for the stratification of osteosarcoma patients into low- and high-risk groups. Owing to their involvement in drug action these genes may further be potential targets for the modulation of drug sensitivity.