Abstract
Abstract Background: The most common genetic abnormality in pancreatic cancer is oncogenic mutation of KRAS, which is an initial key event in pancreatic carcinogenesis. Oncogenic KRAS activates downstream signaling pathways, such as PI3K and MAPK pathways, indicating the essential role of phosphorylation in pancreatic cancer. However, the effect of KRAS on the global phosphoproteome in pancreatic cancer has not been fully elucidated. We investigated proteomic and phosphoproteomic alterations induced by oncogenic Kras using mouse pancreatic cancer cell lines established from doxycycline-inducible KrasG12D pancreatic cancer mouse model. Materials and Methods: Three mouse pancreatic cancer cell lines were established from triple transgenic inducible KrasG12D pancreatic cancer mouse model (tetO_LSL- KrasG12D; ROSA26A-LSL-rtTA-IRES-GFP; p48-Cre). To identify direct downstream pathways of Kras, we performed two different experiments for each cell line: (1) 20 hours Kras-off followed by 5 hours Kras-on (designated “Re-on”) vs. 25 hours Kras-off, and (2) Continuous Kras-on (designated “On”) vs. 24 hours Kras-off. Whole cell lysates were fractionated and subjected to analysis with using mass spectrometry. Results and Conclusion: Overall 4,133 phosphorylation sites were identified. Phosphorylation levels of 2,670 sites were quantified in at least one sample, including 2,347 (87.9%) at serine, 293 (11.0%) threonine, and 30 (1.1%) tyrosine residues. Phosphorylation levels were more than 1.25 fold higher at 386 sites (139 proteins) and 558 sites (256 proteins) in “Re-on” and “On” samples, respectively. 190 sites were common between “Re-on” and “On”, 196 sites were “Re-on” unique, and 368 sites were “On” unique. mTOR and MAPK pathways were activated in both “Re-on” and “On”, while Rho kinase, Phospholipase C, and Rac signaling pathways were predominantly associated with “On”, suggestive of differential downstream pathway activation at different phases of Kras signaling. This abstract is also presented as Poster A21. Citation Format: Ayumu Taguchi, Avnish Kapoor, Amin Momin, Hiroyuki Katayama, Wantong Yao, Hong Wang, Haoqiang Ying, Ronald DePinho, Samir Hanash. Global quantitative proteomic and phosphoproteomic analysis of oncogenic Kras-driven mouse pancreatic cancer. [abstract]. In: Proceedings of the AACR Special Conference on RAS Oncogenes: From Biology to Therapy; Feb 24-27, 2014; Lake Buena Vista, FL. Philadelphia (PA): AACR; Mol Cancer Res 2014;12(12 Suppl):Abstract nr PR03. doi: 10.1158/1557-3125.RASONC14-PR03
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
