Review for 10.1186/1471-230X-10-15 (2010)

Reviewer's report
Title:IkappaBalpha polymorphism at promoter region (rs2233408) influences the
susceptibility of gastric cancer in Chinese
Version: 1Date:17 November 2009
Reviewer: Laura Ottini
Reviewer's report:
IkB# polymorphism at promoter region (rs2233408) influences the susceptibility
of gastric cancer in Chinese
by Shiyan Wang et al.
The paper by Wang et al. investigated the possible effect of the IkB# promoter
polymorphism rs2233408 on the risk of gastric cancer in Chinese population.
This is topic deserves to be addressed since it has been investigated so far in
inflammatory disease and different kinds of cancer, but not in gastric cancer.
General
1. Is the question posed by the authors new and well defined? Partially new and
well defined
2. Are the methods appropriate and well described, and are sufficient details
provided to replicate the work? Not entirely, see comments
3. Are the data sound and well controlled? Partially, see comments below
4. Does the manuscript adhere to the relevant standards for reporting and data
deposition? Yes
5. Are the discussion and conclusions well balanced and adequately supported
by the data? Partially, see comments
6. Are limitations of the work clearly stated? No
7. Do the authors clearly acknowledge any work upon which they are building,
both published and unpublished? Yes
8. Do the title and abstract accurately convey what has been found? Yes
9. Is the writing acceptable? Yes
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Major Compulsory Revisions (that the author must respond to before a decision
on publication can be reached)
Abstract
Methods: Replace the statement “ A total of 1010 gastric cancer patients and
1500 healthy controls..” with a clear description of the number of cases and
controls that were analysed in the study.
Introduction
Add a brief description of the functional relevance of the I#B# promoter
polymorphisms. The reason why the authors focused on the I#B# rs2233408 is
not clear and should be explained.
Methods
The subjects section is confusing. More details should be given about sampling
procedure within the cohort. Clarify the number of cases and controls that were
analysed in the study. As reported, 823 of the 1010 gastric cancer patients
enrolled had sufficient clinical information available. However, it can be inferred
from table 1 that only 564 cases were analysed. Provide a justification of this
large reduction. 1500 healthy subjects were included in the study. Specify how
these control subjects were selected. The Authors affirm that 487 age and
gender matched control subjects were selected for the study. However, it can be
inferred from tables 1- 4 that 566 controls were analysed. It would be also
important to show the gender distribution among cases and controls. The
Authors should indicate the power of the study.
Results
pag.8 “suggesting a dominative effect of deletion allele”, the meaning of this
sentence is not clear to me. Do the Authors suggest a dominant effect of the T
allele? It would better to show data according to dominant, recessive and
co-dominant transmission models.
The reason why the authors have chosen the age 40 years as the cut-off value is
not clear and should be explained.
The number of cases analysed vary within the tables (tables 2, 3, 4). Add
footnotes in tables providing explanation.
Level of interest: An article whose findings are important to those with closely
related research interests
Quality of written English: Acceptable
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