Reviewer's report
Title:Luteolin decreases IGF-II production and down-regulates insulin-like
growth factor-I receptor signaling in HT-29 human colon cancer cells
Version: 1Date:25 July 2011
Reviewer: Thomas THS Haarmann-Stemmann
Reviewer's report:
In this study Lim et al. investigated the effect of luteolin exposure on insulin-like
growth factor receptor signaling in a human colon cancer cell line. The authors
observed that luteolin decreases IGF-II expression and damps IGF-IR signaling
and conclude that this may lead to induction of cell-cycle arrest and programmed
cell death in their test system. The manuscript is nicely arranged and the
introduction provides the necessary background information. The presentation
and discussion of the results is ok, but can be enhanced (see below). In my point
of view, one important experiment is missing.
The majority of the described effects of luteolin on IGF/IGF-R signal transduction
were previously demonstrated in other test systems, e.g. prostate cancer cells.
However, I think the article by Lim et al. is still of interest for scientist working on
the field.
Listed below are several points which should be addressed by the authors before
I can recommend the publication of this article in BMC Gastroenetreology:
- Discretionary Revisions
0) In figures 3 and 4 the densitometry of the single bands is given in numbers
above the respective gel picture. I think the effects will become more visible if the
authors just add the respective column diagrams (as done for the other figures)
1) Luteolin is known to bind to certain cellular receptors, e.g. the aryl
hydrocarbon receptor. Therefore it would be interesting to know, if the
luteolin-mediated inhibition of IGF-II secretion (figure 1) occurs on transcriptional
or post-transcriptional level? I strongly recommend to figure this out by adding an
experiment using cycloheximide and actinomycin D, respectively.
- Minor Essential Revisions
2) The solvent for luteolin is missing and should be added. Did the authors
include the respective solvent controls in their experiments?
3) The sequences of the oligonucleotides used for PCR are missing and should
be added.
- Major Compulsory Revisions
4) The analysis of the effect of luteolin on ERK1/2 phosphorylation stands
isolated in the manuscript. The authors discuss that the luteolin-mediated
inhibition of ERK1/2 phosphorylation probably leads to inactivation of cdc25c in
their test system. This would be indeed an important finding since the activation
status of cdc25c represents an important link between the current article and the
previously published results of the group. Therefore, the authors should add an
experiment where they examine cdc25c phosphorylation in absence/presence of
luteolin.
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Needs some language corrections before being
published
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interests.
Reviewer's report
Title:Luteolin decreases IGF-II production and down-regulates insulin-like
growth factor-I receptor signaling in HT-29 human colon cancer cells
Version: 1Date:25 July 2011
Reviewer: Thomas THS Haarmann-Stemmann
Reviewer's report:
In this study Lim et al. investigated the effect of luteolin exposure on insulin-like
growth factor receptor signaling in a human colon cancer cell line. The authors
observed that luteolin decreases IGF-II expression and damps IGF-IR signaling
and conclude that this may lead to induction of cell-cycle arrest and programmed
cell death in their test system. The manuscript is nicely arranged and the
introduction provides the necessary background information. The presentation
and discussion of the results is ok, but can be enhanced (see below). In my point
of view, one important experiment is missing.
The majority of the described effects of luteolin on IGF/IGF-R signal transduction
were previously demonstrated in other test systems, e.g. prostate cancer cells.
However, I think the article by Lim et al. is still of interest for scientist working on
the field.
Listed below are several points which should be addressed by the authors before
I can recommend the publication of this article in BMC Gastroenetreology:
- Discretionary Revisions
0) In figures 3 and 4 the densitometry of the single bands is given in numbers
above the respective gel picture. I think the effects will become more visible if the
authors just add the respective column diagrams (as done for the other figures)
1) Luteolin is known to bind to certain cellular receptors, e.g. the aryl
hydrocarbon receptor. Therefore it would be interesting to know, if the
luteolin-mediated inhibition of IGF-II secretion (figure 1) occurs on transcriptional
or post-transcriptional level? I strongly recommend to figure this out by adding an
experiment using cycloheximide and actinomycin D, respectively.
- Minor Essential Revisions
2) The solvent for luteolin is missing and should be added. Did the authors
include the respective solvent controls in their experiments?
3) The sequences of the oligonucleotides used for PCR are missing and should
be added.
- Major Compulsory Revisions
4) The analysis of the effect of luteolin on ERK1/2 phosphorylation stands
isolated in the manuscript. The authors discuss that the luteolin-mediated
inhibition of ERK1/2 phosphorylation probably leads to inactivation of cdc25c in
their test system. This would be indeed an important finding since the activation
status of cdc25c represents an important link between the current article and the
previously published results of the group. Therefore, the authors should add an
experiment where they examine cdc25c phosphorylation in absence/presence of
luteolin.
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Needs some language corrections before being
published
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interests.
Please review this paper.
user
Reviewer's report
Title:Luteolin decreases IGF-II production and down-regulates insulin-like
growth factor-I receptor signaling in HT-29 human colon cancer cells
Version: 1Date:25 July 2011
Reviewer: Thomas THS Haarmann-Stemmann
Reviewer's report:
In this study Lim et al. investigated the effect of luteolin exposure on insulin-like
growth factor receptor signaling in a human colon cancer cell line. The authors
observed that luteolin decreases IGF-II expression and damps IGF-IR signaling
and conclude that this may lead to induction of cell-cycle arrest and programmed
cell death in their test system. The manuscript is nicely arranged and the
introduction provides the necessary background information. The presentation
and discussion of the results is ok, but can be enhanced (see below). In my point
of view, one important experiment is missing.
The majority of the described effects of luteolin on IGF/IGF-R signal transduction
were previously demonstrated in other test systems, e.g. prostate cancer cells.
However, I think the article by Lim et al. is still of interest for scientist working on
the field.
Listed below are several points which should be addressed by the authors before
I can recommend the publication of this article in BMC Gastroenetreology:
- Discretionary Revisions
0) In figures 3 and 4 the densitometry of the single bands is given in numbers
above the respective gel picture. I think the effects will become more visible if the
authors just add the respective column diagrams (as done for the other figures)
1) Luteolin is known to bind to certain cellular receptors, e.g. the aryl
hydrocarbon receptor. Therefore it would be interesting to know, if the
luteolin-mediated inhibition of IGF-II secretion (figure 1) occurs on transcriptional
or post-transcriptional level? I strongly recommend to figure this out by adding an
experiment using cycloheximide and actinomycin D, respectively.
- Minor Essential Revisions
2) The solvent for luteolin is missing and should be added. Did the authors
include the respective solvent controls in their experiments?
3) The sequences of the oligonucleotides used for PCR are missing and should
be added.
- Major Compulsory Revisions
4) The analysis of the effect of luteolin on ERK1/2 phosphorylation stands
isolated in the manuscript. The authors discuss that the luteolin-mediated
inhibition of ERK1/2 phosphorylation probably leads to inactivation of cdc25c in
their test system. This would be indeed an important finding since the activation
status of cdc25c represents an important link between the current article and the
previously published results of the group. Therefore, the authors should add an
experiment where they examine cdc25c phosphorylation in absence/presence of
luteolin.
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Needs some language corrections before being
published
Statistical review: No, the manuscript does not need to be seen by a
statistician.
Declaration of competing interests:
I declare that I have no competing interests.
assistant