Review for 10.1186/s12876-020-01383-z (2020)

Reviewer’ s report
Title: Transcriptomic analysis on the effects of melatonin in gastrointestinal carcinomas
Version: 0Date: 08 Apr 2020
Reviewer: Peter Schemmer
Reviewer's report:
Lu Ao et al. tried to give in their manuscript entitled "Transcriptomic analysis on the effects of
melatonin in gastrointestinal carcinomas" to give a comprehensive understanding of the effects ofmelatonin on gastrointestinal carcinomas. The topic is hot because there is a lot of research goingon in order to minimize chemoresistance and side effects of chemotherapeutics on the one handand increase the success of chemotherapy.The experiments were performed using gastric cancer cell line HGC-27 and colorectaladenocarcinoma cell line HCT-8 cells as well as the human hepatocellular carcinoma cell linesHepG2 and Huh-7.Interestingly, the authors described 4 common pathways enriched by those DEGs which wereupregulated in three cancers but downregulated in all four cell lines treated by melatonin,including ribosome biogenesis in eukaryotes, RNA transport, spliceosome and cell cycle signalingpathways. These results suggest that melatonin might exert antitumor effects through thesepathways. The authors investigated the effects of melatonin on chemoresistance and could showthat Melatonin exerts the effects of pro-apoptosis and anti-proliferation on gastrointestinalcarcinoma cel llines, and might increase the sensitivity of 5-FU in gastric cancer and colorectalcancer.The authors are aware of the fact that this study is performed under "laboratory conditions" and in
vivo experiments should be performed in order to get more detailed insights in the processes
caused by the administration of melatonin.
The authors should mention in their introduction different additives and substances which are
under investigation in chemotherapeutic regimens such as glycine (Dietary glycine decreases bothtumor volume and vascularization in a combined colorectal liver metastasis and chemotherapymodel. Maneikyte J, Bausys A, Leber B, Horvath A, Feldbacher N, Hoefler G, Strupas K, StieglerP, Schemmer P.), and broccoli sprout (Broccoli sprout supplementation in patients with advancedpancreatic cancer is difficult despite positive effects-results from the POUDER pilot study.Lozanovski VJ, Polychronidis G, Gross W, Gharabaghi N, Mehrabi A, Hackert T, Schemmer P,Herr I.Invest New Drugs. 2019 Jun 27).
Are the methods appropriate and well described?
If not, please specify what is required in your comments to the authors.
Yes
Does the work include the necessary controls?
If not, please specify which controls are required in your comments to the authors.
YesAre the conclusions drawn adequately supported by the data shown?
If not, please explain in your comments to the authors.
Yes
Are you able to assess any statistics in the manuscript or would you recommend an
additional statistical review?If an additional statistical review is recommended, please specify what aspects require furtherassessment in your comments to the editors.
I recommend additional statistical reviewQuality of written English
Please indicate the quality of language in the manuscript:
Needs some language corrections before being publishedDeclaration of competing interests
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