TY  - JOUR
AB  - Background: No reliable predictors of susceptibility to gemcitabine chemotherapy exist in pancreatic ductal adenocarcinoma (PDAC). MicroRNAs (miR) are epigenetic gene regulators with tumorsuppressive or oncogenic roles in various carcinomas. This study assesses chemoresistant PDAC for its specific miR expression pattern. Methods: Gemcitabine-resistant variants of two mutant p53 human PDAC cell lines were established. Survival rates were analyzed by cytotoxicity and apoptosis assays. Expression of 1733 human miRs was investigated by microarray and validated by qRT-PCR. After in-silico analysis of specific target genes and proteins of dysregulated miRs, expression of MRP-1, Bcl-2, mutant p53, and CDK1 was quantified by Western blot. Results: Both established PDAC clones showed a significant resistance to gemcitabine (p<0.02) with low apoptosis rate (p<0.001) vs. parental cells. MiR-screening revealed significantly upregulated (miR-21, miR-99a, miR-100, miR-125b, miR-138, miR-210) and downregulated miRs (miR-31*, miR-330, miR-378) in chemoresistant PDAC (p<0.05). Bioinformatic analysis suggested involvement of these miRs in pathways controlling cell death and cycle. MRP-1 (p<0.02) and Bcl-2 (p<0.003) were significantly overexpressed in both resistant cell clones and mutant p53 (p = 0.023) in one clone. Conclusion: Consistent miR expression profiles, in part regulated by mutant TP53 gene, were identified in gemcitabine-resistant PDAC with significant MRP-1 and Bcl-2 overexpression. These results provide a basis for further elucidation of chemoresistance mechanisms and therapeutic approaches to overcome chemoresistance in PDAC.
AU  - Dhayat, Sameer
AU  - Mardin, Wolf Arif Mithat
AU  - Seggewiß, Jochen
AU  - Ströse, Anda Jana
AU  - Matuszcak, Christiane
AU  - Hummel, Richard
AU  - Senninger, Norbert
AU  - Mees, Sören Torge
AU  - Haier, Jörg
DA  - 2015-11-25
DO  - 10.1371/journal.pone.0143755
LA  - eng
N1  - PLoS ONE 10 (2015) 11, e0143755, 1-21
N1  - Finanziert durch den Open-Access-Publikationsfonds 2015/2016 der Westfälischen Wilhelms-Universität Münster (WWU Münster).
PY  - 2015-11-25
SN  - 1932-6203
TI  - MicroRNA Profiling Implies New Markers of Gemcitabine Chemoresistance in Mutant p53 Pancreatic Ductal Adenocarcinoma
UR  - https://nbn-resolving.org/urn:nbn:de:hbz:6-76229530002
Y2  - 2024-11-22T05:34:59
ER  -