Related Experiment Video
Updated: Sep 5, 2025
07:08
Fully Processed Recombinant KRAS4b: Isolating and Characterizing the Farnesylated and Methylated Protein
Published on: January 16, 2020
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Mutant KRAS-Associated Proteome Is Mainly Controlled by Exogenous Factors
Patrícia Dias Carvalho1,2,3, Flávia Martins1,2,4, Joana Carvalho1,2
1Instituto de Investigação e Inovação em Saúde (i3S), Rua Alfredo Allen 208, 4200-135 Porto, Portugal.
Cells
|July 9, 2022
Summary
Mutant KRAS signaling is influenced by the tumor microenvironment, impacting colorectal cancer cell responses. Understanding these KRAS-non-autonomous mechanisms is key for developing new cancer therapies.
Area of Science:
- Oncology
- Molecular Biology
- Cancer Signaling
Background:
- Mutant KRAS signaling is crucial in colorectal cancer, but its modulation by external factors and resistance mechanisms remain incompletely understood.
- Identifying KRAS-autonomous versus KRAS-non-autonomous signaling is vital for discovering new therapeutic targets in mutant KRAS cancers.
Purpose of the Study:
- To investigate how mutant KRAS signaling in colorectal cancer cells responds to fibroblast-secreted factors.
- To differentiate KRAS-autonomous and KRAS-non-autonomous mechanisms in response to tumor microenvironment stimuli.
Main Methods:
- Proteomic analysis of two mutant KRAS colorectal cancer cell lines (HCT116 and LS174T) after KRAS silencing and treatment with rhTGFβ1-activated fibroblast secretome.
- Assessment of KRAS-dependent and fibroblast-dependent proteome alterations.
Main Results:
- Fibroblast-secreted factors induced cell line-specific proteome changes, with mutant KRAS governing a significant portion (43% in HCT116, 38% in LS174T).
- A majority of KRAS-associated proteins were regulated in a KRAS-non-autonomous manner, dependent on fibroblast factors (67% in HCT116, 78% in LS174T).
- KRAS-non-autonomous pathways differed between cell lines, involving proteoglycans in cancer, p53, and Rap1 signaling (HCT116) or cell-spreading and metabolism (LS174T).
Conclusions:
- Mutant KRAS signaling is highly context-dependent, influenced significantly by the tumor microenvironment.
- Therapeutic strategies for mutant KRAS cancers should consider the tumor microenvironment's role in modulating signaling pathways.
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