MEK162 for Patients With RAS/RAF/MEK Activated Tumors
Ontology highlight
ABSTRACT:
DISEASE(S): Hematologic Neoplasms,Solid Tumor And Hematologic Malignancies
PROVIDER: 2147225 | ecrin-mdr-crc |
REPOSITORIES: ECRIN MDR
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2011-07-07 | GSE29308 | GEO
Project description:An inducible oncogenic cell line ZFL-?Raf1-ER was established, in which oncogenic human Raf-1(?Raf1) can be activated in zebrafish liver cells by administration of 4-hydroxytamoxifen (4HT). Transcriptional profilling of the ZFL-?Raf1-ER cells with and without administration of 4HT and/or the MEK inhibitor U0126 defined the gene signatures transcriptionally regulated by hyperactive Raf/MEK/MAPK signaling in zebrafish liver cells. The ZFL-?Raf1-ER cells were cultured in 12-well plates till confluence. Cell were starved for 4h in plain medium and susequently treated with or without 1µM 4HT and/or 30µM U0126 for 12h. Biological triplications were taken for each condition.
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Project description:BackgroundColorectal cancer (CRC) is one of the most common malignancies, and it's expected that the CRC burden will substantially increase in the next two decades. New biomarkers for targeted treatment and associated molecular mechanism of tumorigenesis remain to be explored. In this study, we investigated whether PDCD6 plays an oncogenic role in colorectal cancer and its underlying mechanism.MethodsProgrammed cell death protein 6 (PDCD6) expression in CRC samples were analyzed by immunohistochemistry and immunofluorescence. The prognosis between PDCD6 and clinical features were analyzed. The roles of PDCD6 in cellular proliferation and tumor growth were measured by using CCK8, colony formation, and tumor xenograft in nude mice. RNA-sequence (RNA-seq), Mass Spectrum (MS), Co-Immunoprecipitation (Co-IP) and Western blot were utilized to investigate the mechanism of tumor progression. Immunohistochemistry (IHC) and quantitative real-time PCR (qRT-PCR) were performed to determine the correlation of PDCD6 and MAPK pathway.ResultsHigher expression levels of PDCD6 in tumor tissues were associated with a poorer prognosis in patients with CRC. Furthermore, PDCD6 increased cell proliferation in vitro and tumor growth in vivo. Mechanistically, RNA-seq showed that PDCD6 could affect the activation of the MAPK signaling pathway. PDCD6 interacted with c-Raf, resulting in the activation of downstream c-Raf/MEK/ERK pathway and the upregulation of core cell proliferation genes such as MYC and JUN.ConclusionsThese findings reveal the oncogenic effect of PDCD6 in CRC by activating c-Raf/MEK/ERK pathway and indicate that PDCD6 might be a potential prognostic indicator and therapeutic target for patients with colorectal cancer.
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