trichostatin-a and Carcinoma--Pancreatic-Ductal

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal of all human cancers with a high mortality rate. Resistance to conventional treatments and chemotherapeutics is a typical feature of PDAC. To investigate the causes of drug resistance it is essential to deeply investigate the mechanism of action of chemotherapeutics. In this study, we performed an in depth shotgun proteomic approach using the label-free proteomic SWATH-MS analysis to investigate novel insights of the mechanism of action of the histone deacetylase (HDAC) inhibitor trichostatin A (TSA) in PDAC cells. This proteomic analysis in PaCa44 cells and data elaboration of TSA-regulated proteins by bioinformatics showed an overall up-regulation of cytokeratins and other proteins related to the cytoskeleton organization, keratinization, and apoptotic cell death. On the contrary, a large amount of the down-regulated proteins by TSA treatment belongs to the cellular energetic metabolism and to the machinery of protein synthesis, such as ribosomal proteins, determining synergistic cell growth inhibition by the combined treatment of TSA and the glycolytic inhibitor 2-deoxy-d-glucose in a panel of PDAC cell lines. Data are available via ProteomeXchange with identifier PXD007801.

Topics: Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Cytoskeleton; Energy Metabolism; Humans; Hydroxamic Acids; Pancreatic Neoplasms; Proteomics

Our research group recently reported that pancreatic endocrine cancer cell lines are sensitive to the HDAC inhibitor trichostatin A (TSA). In the present paper, we show that the combined treatment of pancreatic endocrine tumour cell lines with TSA and the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (DAC) determines a strong synergistic inhibition of proliferation mainly due to apoptotic cell death. Proteomic analysis demonstrates that the modulation of specific proteins correlates with the antiproliferative effect of the drugs. A schematic network clarifies the most important targets or pathways involved in pancreatic endocrine cancer growth inhibition by single or combined drug treatments, which include proteasome, mitochondrial apoptotic pathway and caspase related proteins, p53 and Ras related proteins. A comparison between the patterns of proteins regulated by TSA or DAC in endocrine and ductal pancreatic cancer cell lines is also presented.

Topics: Analysis of Variance; Apoptosis; Azacitidine; Carcinoma, Pancreatic Ductal; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Decitabine; Drug Synergism; Endocrine Gland Neoplasms; Enzyme Inhibitors; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Humans; Hydroxamic Acids; Pancreatic Neoplasms

Using microarrays, we have screened for genes reactivated by drugs that modify epigenetic mechanisms in pancreatic cancer cells. One of the genes identified was tissue factor pathway inhibitor 2 (TFPI-2), which encodes for a broad-spectrum serine proteinase inhibitor that negatively regulates the extracellular matrix degradation, an essential step in tumor invasion and metastasis. We therefore investigated the expression and methylation patterns of the TFPI-2 gene in pancreatic adenocarcinoma, and determined its role in tumor growth and invasion. In contrast to its abundant expression in normal pancreas, TFPI-2 mRNA was undetectable in a high fraction of pancreatic cancer cell lines and in primary pancreatic ductal neoplasms (IPMNs). Loss of TFPI-2 expression was associated with aberrant hypermethylation of its promoter CpG island. Treatment with the phorbol ester (PMA), known to stimulate the TFPI-2 promoter activity, augmented the TFPI-2 expression in cell lines with unmethylated or partially methylated TFPI-2, but failed to induce the expression in cell lines that harbored fully methylated TFPI-2. Aberrant methylation of TFPI-2 was also detected in 73% (102/140) of pancreatic cancer xenografts and primary pancreatic adenocarcinomas, was more likely in older patients with pancreatic cancer, and significantly correlated with progression of IPMNs (P=0.0002). Restored expression of the TFPI-2 gene in nonexpressing pancreatic cancer cells resulted in marked suppression in their proliferation, migration, and invasive potential in vitro. We thus conclude that epigenetic inactivation of TFPI-2 is a common mechanism that contributes to the aggressive phenotype of pancreatic ductal adenocarcinoma.

Topics: Adenocarcinoma; Antimetabolites, Antineoplastic; Azacitidine; Base Sequence; Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Decitabine; DNA Primers; Glycoproteins; Humans; Hydroxamic Acids; Loss of Heterozygosity; Oligonucleotide Array Sequence Analysis; Pancreatic Neoplasms; Reverse Transcriptase Polymerase Chain Reaction; Transplantation, Heterologous

Our previous study indicated that DUSP6/MKP-3/PYST1 could act as a tumor suppressor in human pancreatic cancer. DUSP6 was frequently underexpressed in primary pancreatic cancer tissues by an unknown mechanism. In this study, we demonstrated that hypermethylation of the expressional control region of DUSP6 could account for its abrogation in cultured human pancreatic cancer cells and in primary pancreatic cancer tissues. First, we checked intrinsic transcriptional expression levels of DUSP6 by a quantitative real time PCR assay in 16 cultured pancreatic cancer cell lines and found that the cells could be classified into four groups: very-low-level expression, low-level expression, high-level expression, and very-high-level expression. We observed restored expression of DUSP6 after treatment with 5-azacytidine and trichostatin A, a DNA methyltransferase inhibitor and a histone deacetylase inhibitor, respectively, in cells with intrinsically very-low-level and low-level expression of DUSP6. Using a sodium-bisulfite-modification assay, we found that CpG sequences in intron 1 of DUSP6 were heavily methylated in MIA PaCa-2 and PAN07JCK, both showing the very low level of intrinsic expression of the gene. On the other hand, no methylation in this region was detected in 14 other cell lines. We checked the methylation state of this region by a methylation-specific PCR method in 12 primary pancreatic cancer tissues and compared it with the expression state of DUSP6 investigated by immunohistochemistry. Methylation was detected in five of eight cases with abolished expressions of DUSP6, four of which were poorly differentiated adenocarcinoma. On the other hand, none of the four cases with preserved expression of DUSP6 showed methylation. The methylation state significantly correlated with both the abolishment of protein expression (p = 0.038) and the histological subtype of adenocarcinoma (p = 0.023) by chi-square test. These results indicate that hypermethylation of the CpG islands in intron 1 may account for the strong suppression of DUSP6 expression. Other mechanism(s) and/or other CpG sites outside of our investigation may have some influence upon expressional suppression. Our combined results suggest that hypermethylation with modification of histone deacetylation play an important role in transcriptional suppression of DUSP6 in human pancreatic cancer.

Topics: Acetylation; Adenocarcinoma; Azacitidine; Base Sequence; Carcinoma, Pancreatic Ductal; Cell Differentiation; CpG Islands; DNA Methylation; Dual Specificity Phosphatase 6; Enzyme Inhibitors; Gene Expression Regulation, Neoplastic; Gene Silencing; Histone Deacetylase Inhibitors; Histones; Humans; Hydroxamic Acids; Molecular Sequence Data; Neoplasm Invasiveness; Pancreatic Neoplasms; Protein Tyrosine Phosphatases; Tumor Cells, Cultured

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is an increasingly identified precursor to infiltrating ductal adenocarcinoma. Although our knowledge of the clinical and pathologic features of IPMNs is increasing, the molecular mechanisms underlying these neoplasms remain poorly understood.. To provide further insight into the molecular pathobiology of IPMNs, global expression profiling was done to determine genes that are inactivated/down-regulated in IPMNs using oligonucleotide microarrays (Affymetrix).. In total, 300 unique transcripts (217 known genes) were identified as highly underexpressed in 12 IPMNs (<10-fold lower and P < 0.05) compared with five normal pancreatic ductal epithelium samples obtained by laser capture microdissection. The differential expression of a selection of genes was confirmed using reverse-transcription PCR. One of the genes underexpressed at both the transcriptional and protein level in a significant proportion of IPMNs was the cyclin-dependent kinase inhibitor, CDKN1C/p57KIP2. CDKN1C expression was also decreased in many pancreatic cancer cell lines and was restored following treatment with a DNA methylation inhibitor (5-aza-2'-deoxycitidine) or, more potently, with a histone deacetylase inhibitor (trichostatin A). Partial methylation of the CDKN1C promoter CpG island was found in most, but not all, pancreatic cancer cell lines with reduced CDKN1C expression, and was also detectable in IPMNs. Furthermore, a subset of pancreatic cancers showed complete hypomethylation of LIT1, an imprinting control region important for the regulation of CDKN1C expression. Complete hypomethylation in these cancers was the result of deletion of the methylated LIT1 allele at 11p15.5 rather than loss of imprinting.. These findings suggest that CDKN1C is commonly down-regulated in pancreatic ductal neoplasms through a combination of promoter hypermethylation, histone deacetylation, and loss of the maternal allele expressing CDKN1C.

Topics: Adenocarcinoma, Mucinous; Adenocarcinoma, Papillary; Azacitidine; Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Cluster Analysis; Cyclin-Dependent Kinase Inhibitor p57; Decitabine; Down-Regulation; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Humans; Hydroxamic Acids; Immunohistochemistry; Oligonucleotide Array Sequence Analysis; Pancreatic Neoplasms; Reverse Transcriptase Polymerase Chain Reaction

In this study, we demonstrate a novel mechanism by which down-regulation of transforming growth factor beta type II receptor (TbetaRII) is mediated by a histone deacetylase (HDAC) in pancreatic ductal adenocarcinoma (PDAC) cells. Treatment of PDAC cell lines BxPC-3 and MIA PaCa-2 with a specific HDAC inhibitor, trichostatin A (TSA), strongly activates TbetaRII promoter activity and induces TbetaRII expression. The transcriptional activation of TbetaRII by TSA was correlated with a decrease in HDAC activity and an increase in acetylated histone H4 protein. Correspondingly, an increase in the association of TbetaRII promoter with acetylated histone H4 was detected in the TSA-treated cells as determined by a chromatin immunoprecipitation assay. We found that a specific Sp1 site (Sp1C, located at -102 bp relative to the transcription start site) adjacent to an inverted CCAAT box (-83 bp) is required for TSA-mediated activation of the TbetaRII promoter. Furthermore, we determined that HDAC1 complexed with Sp1 in PDAC cells and that TSA treatment interfered with this association. Diminished binding of HDAC1 to the -112 to -65 bp region of the TbetaRII promoter after TSA treatment was confirmed by a DNA affinity precipitation assay. This is the first study to demonstrate the requirement of a specific Sp1 site for TSA-mediated transcriptional activation of TbetaRII. This study further suggests that the specificity of this Sp1 site for HDAC-mediated repression of TbetaRII may involve the interaction of the Sp1-HDAC1 complex with components of the cognate transcriptional regulators that bind to the inverted CCAAT box.

Topics: Carcinoma, Pancreatic Ductal; CCAAT-Binding Factor; Down-Regulation; Gene Expression Regulation, Neoplastic; Gene Silencing; Histone Deacetylase Inhibitors; Histone Deacetylases; Histones; Humans; Hydroxamic Acids; Pancreatic Neoplasms; Promoter Regions, Genetic; Protein Serine-Threonine Kinases; Receptor, Transforming Growth Factor-beta Type II; Receptors, Transforming Growth Factor beta; Sp1 Transcription Factor; Transcriptional Activation; Transfection; Tumor Cells, Cultured

A pancreatic adenocarcinoma cell line (Paca44) was treated with trichostatin-A (TSA), a potent inhibitor of histone deacetylases, in order to evaluate the effect of this drug on protein expression. Master maps of control and treated Paca44 cells were generated by analysis with the PDQuest software. The comparison between such maps showed up- and downregulation of 51 polypeptide chains, out of a total of 700 spots detected by a medium-sensitivity stain, micellar Coomassie Brilliant Blue. Fingerprinting by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF)-mass spectrometry analysis enabled the identification of 22 of these spots. Among these proteins, of particular interest are the two downregulated proteins nucleophosmin and translationally controlled tumor protein, as well as the upregulated proteins programmed cell death protein 5 (also designated as TFAR19) and stathmin (oncoprotein 18). The modulation of these four proteins is consistent with our observation that TSA is able to inhibit cell growth of Paca44 by causing cell cycle arrest at the G2 phase and apoptotic cell death.

Topics: Antineoplastic Agents; Carcinoma, Pancreatic Ductal; Cell Division; Cell Line, Tumor; Electrophoresis, Gel, Two-Dimensional; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Proteins; Proteomics; Software; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

We evaluated the biological relevance of maspin expression in pancreatic ductal adenocarcinoma and studied regulatory mechanisms of maspin gene activation in pancreatic carcinoma cell lines. Maspin expression was immunohistochemically detected in a series of 57 pancreatic ductal adenocarcinomas, 51 (90%) of which were classified as high-expressers. In lymph node metastases, maspin expression was somewhat decreasingly found in 39/49 (80%). Maspin high-expressers showed predominantly a low histological grade (p=0.013). Moreover, maspin expression was found in two mixed ductal-endocrine carcinomas, but not in 10 endocrine tumors and the surrounding normal pancreatic tissues. Using a luciferase reporter system, maspin promoter activity was induced in the maspin-positive pancreatic cancer cell lines as well as maspin-negative PANC-1 cells. Additionally, treatment with the DNA methyltransferase inhibitor, 5-aza-2' deoxycytidine, and histone deacetylase inhibitor, trichostatin A, led to re-expression of maspin mRNA in PANC-1 cells. Our results indicate that maspin expression is up-regulated in most if not all pancreatic ductal adenocarcinomas and may be related to the development and differentiation, and that DNA methylation and histone deacetylation may suppress maspin gene activation in pancreatic cancer cells.

Topics: Acetylation; Aged; Azacitidine; Carcinoma, Pancreatic Ductal; Decitabine; DNA Methylation; DNA Modification Methylases; Enzyme Inhibitors; Female; Gene Silencing; Genes, Tumor Suppressor; Histone Deacetylase Inhibitors; Histones; Humans; Hydroxamic Acids; Immunoenzyme Techniques; Lymphatic Metastasis; Male; Middle Aged; Pancreatic Neoplasms; Promoter Regions, Genetic; Proteins; Serpins; Tumor Cells, Cultured; Up-Regulation