biostudies-literatureNath SNCI NIH HHS909-17https://www.ebi.ac.uk/biostudies/studies/S-EPMC4500655biostudies-literatureUnknown44(6)<h4>Objective</h4>Eighty percent of pancreatic ductal adenocarcinomas (PDAs) overexpress mucin 1 (MUC1), a transmembrane mucin glycoprotein. MUC1(high) PDA patients also express high levels of cyclooxygenase 2 (COX-2) and show poor prognosis. The cytoplasmic tail of MUC1 (MUC1-CT) partakes in oncogenic signaling, resulting in accelerated cancer progression. Our aim was to understand the regulation of Cox-2 expression by MUC1.<h4>Methods</h4>Levels of COX-2 and MUC1 were determined in MUC1(-/-), MUC1(low), and MUC1(high) PDA cells and tumors using reverse transcriptase-polymerase chain reaction, Western blot, and immunohistochemistry. Proliferative and invasive potential was assessed using MTT and Boyden chamber assays. Chromatin immunoprecipitation was performed to evaluate binding of MUC1-CT to the promoter of COX-2 gene.<h4>Results</h4>Significantly higher levels of COX-2 mRNA and protein were detected in MUC1(high) versus MUC1(low/null) cells, which were recapitulated in vivo. In addition, deletion of MUC1 gene and transient knockdown of MUC1 led to decreased COX-2 level. Also, MUC1-CT associated with the COX-2 promoter at ∼1000 base pairs upstream of the transcription start site, the same gene locus where nuclear factor κB p65 associates with the COX-2 promoter.<h4>Conclusions</h4>Data supports a novel regulation of COX-2 gene by MUC1 in PDA, the intervention of which may lead to a better therapeutic targeting in PDA patients.PancreasMucin 1 Regulates Cox-2 Gene in Pancreatic Cancer.PMC4500655R01 CA118944-01A1R01 CA118944Rao SMukherjee PNath SRoy LDGrover PfalseMucin 1 Regulates Cox-2 Gene in Pancreatic Cancer.<h4>Objective</h4>Eighty percent of pancreatic ductal adenocarcinomas (PDAs) overexpress mucin 1 (MUC1), a transmembrane mucin glycoprotein. MUC1(high) PDA patients also express high levels of cyclooxygenase 2 (COX-2) and show poor prognosis. The cytoplasmic tail of MUC1 (MUC1-CT) partakes in oncogenic signaling, resulting in accelerated cancer progression. Our aim was to understand the regulation of Cox-2 expression by MUC1.<h4>Methods</h4>Levels of COX-2 and MUC1 were determined in MUC1(-/-), MUC1(low), and MUC1(high) PDA cells and tumors using reverse transcriptase-polymerase chain reaction, Western blot, and immunohistochemistry. Proliferative and invasive potential was assessed using MTT and Boyden chamber assays. Chromatin immunoprecipitation was performed to evaluate binding of MUC1-CT to the promoter of COX-2 gene.<h4>Results</h4>Significantly higher levels of COX-2 mRNA and protein were detected in MUC1(high) versus MUC1(low/null) cells, which were recapitulated in vivo. In addition, deletion of MUC1 gene and transient knockdown of MUC1 led to decreased COX-2 level. Also, MUC1-CT associated with the COX-2 promoter at ∼1000 base pairs upstream of the transcription start site, the same gene locus where nuclear factor κB p65 associates with the COX-2 promoter.<h4>Conclusions</h4>Data supports a novel regulation of COX-2 gene by MUC1 in PDA, the intervention of which may lead to a better therapeutic targeting in PDA patients.2015-01-01T00:00:00Z2015 Aug2024-11-14T09:50:41.303Z2019-03-27T01:55:03ZS-EPMC45006552603512310.1097/MPA.0000000000000371