The Impact of Histone Modifications in Endometriosis Highlights New Therapeutic Opportunities
, Kleio Vrettou 2, Florian Nima Fleckenstein 1,3,* and Stamatios Theocharis 2,*Round 1
Reviewer 1 Report
Thankyou for your article. The following comments are suggested for your consideration:
The title is confusing. Suggest it be changed to 'The impact of histone modifications in endometriosis highlights new therapeutic opportunities. '
Line 52, DNA is “tightly” wrapped around …… to prevent gene transcription.
For improved clarity, Line 53, Histone modifications ‘such as acetylation, deacetylation, methylation and demethylation’ permit the ‘unwrapping of DNA’ and loosening of…..
Provide a schematic diagram of histone modifications to demonstrate the differences between acetylation and methylation epigenetic modifications, then focus on the HDACs.
While HDAC1, HDAC2, HDAC3, Sirtuin 1, and Sirtuin 3, are the five most studied HDAC enzymes in the pathophysiology of endometriosis, what about the enzymes that are missing. As there are currently 18 enzymes, can you suggest why only 5 have been studied, provide a limitations statement to the enzymes not studied
There are 3 HDACI approved for use in humans, vorinostat, romidepsin, and panobinostat, You have discussed vorinostat, romidepsin, why not Panobinostat. If it has not been studied, this needs to be mentioned
Include these reference to the discussion about TSA; Seo SK et al., 2018 Reprod Sci 2018;25:1349-56; have studied TSA on endometriotic stromal cells
Author Response
Thank you for your article. The following comments are suggested for your consideration:
The title is confusing. Suggest it be changed to 'The impact of histone modifications in endometriosis highlights new therapeutic opportunities. '
We have now changed the title to 'The impact of histone modifications in endometriosis highlights new therapeutic opportunities. '
Line 52, DNA is “tightly” wrapped around …… to prevent gene transcription.
We have now applied the suggested modification.
For improved clarity, Line 53, Histone modifications ‘such as acetylation, deacetylation, methylation and demethylation’ permit the ‘unwrapping of DNA’ and loosening of…..
We have now applied the suggested modification.
Provide a schematic diagram of histone modifications to demonstrate the differences between acetylation and methylation epigenetic modifications, then focus on the HDACs.
We have now provided the suggested diagram of histone modifications.
While HDAC1, HDAC2, HDAC3, Sirtuin 1, and Sirtuin 3, are the five most studied HDAC enzymes in the pathophysiology of endometriosis, what about the enzymes that are missing. As there are currently 18 enzymes, can you suggest why only 5 have been studied, provide a limitations statement to the enzymes not studied.
In the Discussion part, we have now provided a limitations statement to the enzymes not studied.
There are 3 HDACI approved for use in humans, vorinostat, romidepsin, and panobinostat. You have discussed vorinostat, romidepsin, why not Panobinostat. If it has not been studied, this needs to be mentioned.
We have now pointed out that we have discussed only vorinostat and romidepsin, because panobinostat has not been studied.
Include these reference to the discussion about TSA; Seo SK et al., 2018 Reprod Sci 2018;25:1349-56; have studied TSA on endometriotic stromal cells.
We have now included the suggested reference to the discussion about TSA.
Reviewer 2 Report
This is a timely review that will benefit from English language usage editing and addressing a few questions/ comments to help the Readers’ understanding.
1. Abstract, last line: suggest change (no such word as “provenly”) …therapeutic targeting have been proven to have a strong impact in….
2. Page 2, before lines 77-78: introduce readers to Sirtuins that you will cover below, e.g., The human sirtuins (SIRT1–SIRT7) are implicated in gene silencing, energy homeostasis, and mitochondrial function (reviewed in (1)). Then say something about each one that you discuss later, e.g. SIRT1 is primarily a nuclear protein that targets the PGC-1α, FOXO, and NF-κB families of transcription factors, among others (ref = (1).
3. Page 2, line 7: add Sirtuins: The Role of HDACs and Sirtuins in the Pathogenesis…
4. Pg. 2, line 90: is this protein or transcript abundance?
5. Pg. 27, line 97: which cell line? (name it)
6. Pg. 3, line 111: remove “exponentiate- use “increase”
7. Pg. 3, line 111: remove “experience”- use show
8. Pg. 2, line 122: in vivo- is this in human patients or an animal model- please state
9. Pg. 3, line 126: remove “ more profound” and use ‘higher’
10. Pg. 3, line 131: remove ,which – use was
11. Pg. 3, line 134-135: in what samples: blood or serum? Samples
12. Pg. 3, line 141: remove “Besides,” just go to Gonazlez-Fenandez et al….
13. Pg. 3, line 144: remove “designated” use demonstrated
14. Pg. 3, line147, need a comma after Last, - correct to Last, but not least,….
15. Pg. 3, line 151-152: remove ”which all three represent” change to GDH, SDH, and MnSOD, all target enzymes of SIRT3 (add a REFERENCE(s)), showed decreased enzyme activities…
16. Table 1: is this ERalpha or ERBeta? Also you discuss GPER1 (note missing 1 in your text- GPER is incorrect, human gene is GPER1) - can you add that to this table?
17. Related to ref. # 62 (2) cited as the ref. for the GPER1 work, that is incorrect- it is actually this reference: (3) which the authors need to correct.
18. Given this error, it is suggested that the authors please double check their referrals to cited work in this paper. (It’s easy to make such errors.)
19. Pg. 4- after line 162- add Introduction of HDAC inhibitors- move to a new section- new 3.1, so 3.1, becomes 3.2, etc. add a table of inhibitors, mechanism, and direct targets
20. Pg. 4, line 168- missing a REFERENCE before the period after “cell viability”
21. Pg. 4, line 171: remove “the animal” and use this
22. Pg. 4, line 175: missing what cell line
23. Pg. 5, line 179: remove “provoking” and use inducing
24. Pg. 5, line 191: missing a reference after endometriosis
25. Pg. 5, line 217: add a conclusion sentence
26. Pg. 5, line 222: delete “study” before group
27. Pg. 5, line 225: delete “highlighted” - use reported
28. Pg. 5, line 227: delete the “Last, but not least, the researchers published in 2010. Just say: In their third published work on this topic, they outlined the TSA-mediated…..
29. Pg. 6, line 236: Add a conclusion sentence
30. Pg. 6, line 242: delete “More accurately,
31. Pg. 6, line 250: delete “could not take place” instead add was also blocked; whereas…
32. COMMENT re pg. 6: lines 255-56-so here increased acetylation of histones is REDUCING GPER1- is this correct?
33. Pg. 9, line 323: change “endorsing” to enhancing.
34. Pg. 9, line 327: delete “severa;’ before women,
35. Pg. 9, line 334: delete “very” before ubiquitous
36. Pg. 9, line 337: …”therapeutic targeting (delete provenly- no such word) – suggest change to: were demonstrated to have a strong impact…
REFERENCES Cited in this review:
37. 1. Chang H-C, Guarente L. SIRT1 and other sirtuins in metabolism. Trends in Endocrinology & Metabolism 2014; 25:138-145
38. 2. Imesch P, Samartzis EP, Schneider M, Fink D, Fedier A. Inhibition of transcription, expression, and secretion of the vascular epithelial growth factor in human epithelial endometriotic cells by romidepsin. Fertil Steril 2011; 95:1579-1583
39. 3. Imesch P, Samartzis EP, Dedes KJ, Fink D, Fedier A. Histone deacetylase inhibitors down-regulate G-protein-coupled estrogen receptor and the GPER-antagonist G-15 inhibits proliferation in endometriotic cells. Fertil Steril 2013; 100:770-776
I have suggested a number of edits in the text as indicated above.
Author Response
This is a timely review that will benefit from English language usage editing and addressing a few questions/ comments to help the Readers’ understanding.
- Abstract, last line: suggest change (no such word as “provenly”) …therapeutic targeting have been proven to have a strong impact in….
We have now applied the suggested correction.
- Page 2, before lines 77-78: introduce readers to Sirtuins that you will cover below, e.g., The human sirtuins (SIRT1–SIRT7) are implicated in gene silencing, energy homeostasis, and mitochondrial function (reviewed in (1)). Then say something about each one that you discuss later, e.g. SIRT1 is primarily a nuclear protein that targets the PGC-1α, FOXO, and NF-κB families of transcription factors, among others (ref = (1).
We have now applied the suggested addition.
- Page 2, line 7: add Sirtuins: The Role of HDACs and Sirtuins in the Pathogenesis…
We have now applied the suggested correction.
- Pg. 2, line 90: is this protein or transcript abundance?
These are the results of immunohistochemical staining of HDAC1/2/3 in the epithelial cell fraction of the endometriotic tissues and for the stromal fraction.
- Pg. 27, line 97: which cell line? (name it)
We have now named the cell line.
- Pg. 3, line 111: remove “exponentiate- use “increase”
We have now applied the suggested correction.
- Pg. 3, line 111: remove “experience”- use show
We have now applied the suggested correction.
- Pg. 2, line 122: in vivo- is this in human patients or an animal model- please state
We have now stated that in vivo refers to mice.
- Pg. 3, line 126: remove “ more profound” and use ‘higher’
We have now applied the suggested correction.
- Pg. 3, line 131: remove ,which – use was
We have now applied the suggested correction.
- Pg. 3, line 134-135: in what samples: blood or serum? Samples
In serum, plasma, urine, and cervical mucus samples.
- Pg. 3, line 141: remove “Besides,” just go to Gonazlez-Fenandez et al….
We have now removed ‘‘Besides’’.
- Pg. 3, line 144: remove “designated” use demonstrated
We have now applied the suggested correction.
- Pg. 3, line147, need a comma after Last, - correct to Last, but not least,….
We now added the comma.
- Pg. 3, line 151-152: remove ”which all three represent” change to GDH, SDH, and MnSOD, all target enzymes of SIRT3 (add a REFERENCE(s)), showed decreased enzyme activities…
We have now applied the suggested correction.
- Table 1: is this ERalpha or ERBeta? Also you discuss GPER1 (note missing 1 in your text- GPER is incorrect, human gene is GPER1) - can you add that to this table?
Both ERalpha and ERbeta. We have now added 1 to GPER1.
- Related to ref. # 62 (2) cited as the ref. for the GPER1 work, that is incorrect- it is actually this reference: (3) which the authors need to correct.
The reviewer must be mistaken, ref. # 62 cited as the ref. for the GPER1 work was reference (3).
- Given this error, it is suggested that the authors please double check their referrals to cited work in this paper. (It’s easy to make such errors.)
We have now double checked the referrals.
- Pg. 4- after line 162- add Introduction of HDAC inhibitors- move to a new section- new 3.1, so 3.1, becomes 3.2, etc. add a table of inhibitors, mechanism, and direct targets
We have now added the suggested introduction, alongside a table of HDACIs.
- Pg. 4, line 168- missing a REFERENCE before the period after “cell viability”
We have now added the missing reference.
- Pg. 4, line 171: remove “the animal” and use this
We have now applied the suggested correction.
- Pg. 4, line 175: missing what cell line
We have now improved the aforementioned sentence.
- Pg. 5, line 179: remove “provoking” and use inducing
We have now applied the suggested correction.
- Pg. 5, line 191: missing a reference after endometriosis
We have now added the missing reference.
- Pg. 5, line 217: add a conclusion sentence
We have now added a conclusion sentence.
- Pg. 5, line 222: delete “study” before group
We have now deleted “study” before group.
- Pg. 5, line 225: delete “highlighted” - use reported
We have now applied the suggested correction.
- Pg. 5, line 227: delete the “Last, but not least, the researchers published in 2010. Just say: In their third published work on this topic, they outlined the TSA-mediated…..
We have now applied the suggested correction.
- Pg. 6, line 236: Add a conclusion sentence
We have now added a conclusion sentence.
- Pg. 6, line 242: delete “More accurately,
We have now deleted “More accurately,’’.
- Pg. 6, line 250: delete “could not take place” instead add was also blocked; whereas…
We have now applied the suggested correction.
- COMMENT re pg. 6: lines 255-56-so here increased acetylation of histones is REDUCING GPER1- is this correct?
Yes, these are the study results of Imesch et al.
- Pg. 9, line 323: change “endorsing” to enhancing.
We have now applied the suggested correction.
- Pg. 9, line 327: delete “severa;’ before women,
We have now deleted ‘‘several’’.
- Pg. 9, line 334: delete “very” before ubiquitous
We have deleted ‘‘very’’.
- Pg. 9, line 337: …”therapeutic targeting (delete provenly- no such word) – suggest change to: were demonstrated to have a strong impact…
We have now made the suggested change.
REFERENCES Cited in this review:
- 1.Chang H-C, Guarente L. SIRT1 and other sirtuins in metabolism. Trends in Endocrinology & Metabolism 2014; 25:138-145
- 2.Imesch P, Samartzis EP, Schneider M, Fink D, Fedier A. Inhibition of transcription, expression, and secretion of the vascular epithelial growth factor in human epithelial endometriotic cells by romidepsin. Fertil Steril 2011; 95:1579-1583
- 3.Imesch P, Samartzis EP, Dedes KJ, Fink D, Fedier A. Histone deacetylase inhibitors down-regulate G-protein-coupled estrogen receptor and the GPER-antagonist G-15 inhibits proliferation in endometriotic cells. Fertil Steril 2013; 100:770-776
