Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Pachymic acid inhibits growth and induces apoptosis of pancreatic cancer in vitro and in vivo by targeting ER stress

ABSTRACT: Background: Pachymic acid (PA) is a purified triterpene extracted from medicinal fungus Poria cocos. In this paper, we investigated the anticancer effects of PA on human chemotherapy resistant pancreatic cancer cells. Methods: Gemcitabine-resistant pancreatic cancer cells PANC-1 and MIA PaCa-2 were used, along with a xenograft model of MIA PaCa-2 cells implanted in mice. Apoptosis was assessed by quantitation of cytoplasmic histone-associated DNA fragments and expression of cleaved PARP. Differential expression of genes was identified using comparative DNA microarray analysis. Protein levels were determined by immunoblotting. Toxicology studies in vivo were assessed by detecting pathological changes in organs and liver enzyme profiles in plasma. Tumor tissues were analyzed by quantification of apoptotic bodies, qRT-PCR and immunoblotting. Principal Findings: PA induced endoplasmic reticulum (ER) stress in chemotherapy resistant pancreatic cancer cells through activation of heat shock response and unfolded protein response related genes, which further triggered apoptosis. The involvement of ER stress was confirmed by increasing expression of XBP-1s, ATF4, Hsp70, CHOP and phospho-eIF2M-NM-1. Moreover, 25 mg kgM-bM-^HM-^R1 of PA significantly suppressed MIA PaCa-2 tumor growth in vivo without toxicity, which correlated with induction of apoptosis, ER stress related genes and proteins expression. Conclusions: Growth inhibition and induction of apoptosis by PA in chemotherapy resistant pancreatic cancer cells were associated with ER stress activation both in vitro and in vivo. Pancreatic cancer cell line treated with pachymic acid vs. control (untreated)

ORGANISM(S): Homo sapiens

SUBMITTER: shujie cheng

PROVIDER: E-GEOD-64111 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Similar Datasets

Project description:The molecular mechanisms underlying exceptional radioresistance in pancreatic cancer remain elusive. In the present study, we established a stable radioresistant pancreatic cancer cell line MIA PaCa-2-R by exposing the parental MIA PaCa-2 cells to fractionated ionizing radiation (IR). Systematic proteomics and bioinformatics comparison of protein expression in MIA PaCa-2 and MIA PaCa-2-R cells revealed that several growth factor- and cytokine-mediated pathways, including the OSM/STAT3, PI3K/AKT and MAPK/ERK pathways, were activated in the radioresistant cells, leading to enhanced cell migration, invasion and epithelial-mesenchymal transition (EMT), and inhibition of apoptosis. We focused functional analysis on one of the most upregulated proteins in the radioresistant cells, CD73, which is a cell surface protein that is overexpressed in a variety types of cancer. Ectopic overexpression of CD73 in the parent cells resulted in radioresistance and conferred resistance to IR-induced apoptosis. Knockdown of CD73 resensitized the radioresistant cells to IR and IR-induced apoptosis. The effect of CD73 on radioresistance and apoptosis is independent of the enzymatic activity of CD73. Further studies suggest that CD73 confers acquired radioresistance in pancreatic cancer cells at least in part through inactivating proapoptotic protein BAD via phosphorylation of BAD at Ser-136. Furthermore, we found that knockdown of CD73 in the radioresistant cells alone reverted the gene expression and phenotype of the radioresistant cells from those of mesenchymal-like cells to the ones of epithelial cells, demonstrating that CD73 upregulation is required for maintaining EMT in the radioresistant cells. Our results support the notion that the enhanced growth factor/cytokine signaling that promotes epithelial-mesenchymal plasticity, and acquisition of cancer stem-like cell properties contributes to acquired radioresistance in the residual surviving cells after fractionated irradiation, and that CD73 is a novel downstream factor of those enhanced signaling and acts to confers acquired radioresistance and maintains EMT in the radioresistant pancreatic cancer cells.

Project description:GNAS, a gene encoding G-protein stimulating alpha subunit, is frequently mutated in intraductal papillary mucinous neoplasms (IPMNs), which is an indolent and slow-growing pancreatic neoplasm that secretes abundant mucin. GNAS mutation is not observed in conventional ductal adenocarcinomas of the pancreas. To determine the functional significance of GNAS mutation in pancreatic ductal cells, we examined in vitro phenotypes and gene expression profiles of cells of pancreatic ductal lineage, HPDE, PK-8, PCI-35, and MIA PaCa-2, with exogenous expression of either wild-type or mutated (R201H) GNAS. We found that exogenous GNAS upregulated intracellular cyclic-adenine monophosphate, particularly in the mutated GNAS transfectants. Exogenous GNAS induced no obvious cell-growth promotion, but induced suppression in some cells. The exogenous GNAS upregulated MUC2 and MUC5AC in HPDE and PK-8, and the latter was most sensitive to exogenous GNAS, exhibiting drastic alteration of the global gene expression that is consistent with that of IPMN. Hence, PK-8 expressing exogenous mutated GNAS may be an ideal in vitro model of IPMN. On the other hand, exogenous GNAS downregulated expression of mucin genes and produced modest alteration of gene expression profiles in PCI-35 and MIA PaCa-2, indicating lower sensitivity to exogenous GNAS. Furthermore, we showed diverse and cell-type specific mucin expression pathways with complicated interactions between signaling pathways of the G-protein coupled receptor (GPCR), the mitogen-activated protein kinase (MAPK), and the phosphatidylinositol 3 kinase (PI3K), in which the GPCR pathway appeared to be dominant in some and the MAPK pathway in others. In conclusion, mutated GNAS found in IPMNs may extensively alter gene expression profiles, including expression of mucin genes, with the interaction with MAPK and PI3K pathways in pancreatic ductal-lineage cells, which may determine the characteristic phenotype of the neoplasm. Cells of pancreatic cancer cell lines, PK-8, PCI-35,and MIA PaCa-2, were seeded at 4 M-CM-^W 10^5 cells/well in 6-well plates and incubated for 24 hours at 37M-BM-0C in 5% CO2 with humid atmosphere. Then the cells were transfected with either pcDNA 3.1/V5-His vector or pcDNA3.1-GNAS(R201H)-V5-His vector using Lipofectamine 2000 reagent (Life Technologies) according to the manufacturerM-bM-^@M-^Ys recommendations. The cells were incubated for 24 hours and collected by dissociation using trypsin. Total RNAs were isolated using the RNeasy Mini kit (Qiagen, Hilden, Germany). Serial analysis of gene expression (SAGE) library was constructed using a SOLiD SAGE Kit (Life Technologies) according to the manufactureM-bM-^@M-^Ys instruction. The constructed libraries were analysed by means of the massively parallel sequencing method using SOLiD 4 System (Life Technologies). The SAGE analysis was performed for samples obtained from single transfection experiment.

Dataset Information

Pachymic acid inhibits growth and induces apoptosis of pancreatic cancer in vitro and in vivo by targeting ER stress

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure