- Library Home /
- Search Collections /
- Open Collections /
- Browse Collections /
- UBC Theses and Dissertations /
- Activation of stress-activated kinases and inhibition...
Open Collections
UBC Theses and Dissertations
UBC Theses and Dissertations
Activation of stress-activated kinases and inhibition of PI 3-K/PKB and p70S6K mitogenic signaling pathway by photodynamic therapy in murine keratinocytes Tao, Jing-song
Abstract
Photodynamic therapy (PDT) is a new anti-cancer modality. It involves the use of photosensitizer molecules and a specific wavelength of visible light. The process of PDT generates singlet oxygen and other reactive oxygen intermediates (ROI). Cellular responses to PDT include induction of the early-response gene, release of cytokine, and apoptosis. Many of these cellular events are also known to be regulated by signaling pathways including members of the MAPK family and the PI 3-K/PKB/p70[sup S6K] mitogenic signaling pathway. We investigated the activation status of mitogen-activated protein kinases (MAPKs) and the phosphatidylinositol-3-kinase (PI3-K)/protein kinase B (PKB)/ p70[sup S6K] pathway following PDT treatment. We demonstrate here that PDT caused a marked, dose- and time-dependent activation of both stress-activated protein kinase (SAPK) and p38 HOG1 without affecting the activity of ERK1 or ERK2. However, under similar experimental conditions, PDT concomitantly inhibits the activity and phosphorylation of p70[sup S6K] in cells maintained in a serum-containing medium. In serum-starved Pam 212 cells, PDT inhibited the activation of PI3-K, PKB , and p70[sup S6K] induced by insulin treatment. At present, we do not understand the mechanisms for PDT-induced signaling events nor do we know the potential implications of our findings. However, some of the possible mechanisms and potential implications are discussed.
Item Metadata
Title |
Activation of stress-activated kinases and inhibition of PI 3-K/PKB and p70S6K mitogenic signaling pathway by photodynamic therapy in murine keratinocytes
|
Creator | |
Publisher |
University of British Columbia
|
Date Issued |
1998
|
Description |
Photodynamic therapy (PDT) is a new anti-cancer modality. It involves the use of
photosensitizer molecules and a specific wavelength of visible light. The process of PDT
generates singlet oxygen and other reactive oxygen intermediates (ROI). Cellular responses
to PDT include induction of the early-response gene, release of cytokine, and apoptosis.
Many of these cellular events are also known to be regulated by signaling pathways including
members of the MAPK family and the PI 3-K/PKB/p70[sup S6K] mitogenic signaling pathway. We
investigated the activation status of mitogen-activated protein kinases (MAPKs) and the
phosphatidylinositol-3-kinase (PI3-K)/protein kinase B (PKB)/ p70[sup S6K] pathway following
PDT treatment. We demonstrate here that PDT caused a marked, dose- and time-dependent
activation of both stress-activated protein kinase (SAPK) and p38 HOG1 without affecting
the activity of ERK1 or ERK2. However, under similar experimental conditions, PDT
concomitantly inhibits the activity and phosphorylation of p70[sup S6K] in cells maintained in a
serum-containing medium. In serum-starved Pam 212 cells, PDT inhibited the activation of
PI3-K, PKB , and p70[sup S6K] induced by insulin treatment. At present, we do not understand the
mechanisms for PDT-induced signaling events nor do we know the potential implications of
our findings. However, some of the possible mechanisms and potential implications are
discussed.
|
Extent |
21525111 bytes
|
Genre | |
Type | |
File Format |
application/pdf
|
Language |
eng
|
Date Available |
2009-06-02
|
Provider |
Vancouver : University of British Columbia Library
|
Rights |
For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.
|
DOI |
10.14288/1.0088761
|
URI | |
Degree | |
Program | |
Affiliation | |
Degree Grantor |
University of British Columbia
|
Graduation Date |
1998-05
|
Campus | |
Scholarly Level |
Graduate
|
Aggregated Source Repository |
DSpace
|
Item Media
Item Citations and Data
Rights
For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.