EZH2 Inhibition Sensitizes IDH1R132H-Mutant Gliomas to Histone Deacetylase Inhibitor
, Franklin Garcia 1, Angeliki Mela 1, Liang Lei 2, Pavan Upadhyayula 2, Aayushi Mahajan 2, Nelson Humala 2, Lisa Manier 3, Richard Caprioli 3, Alfredo Quiñones-Hinojosa 4, Patrizia Casaccia 5 and Peter Canoll 1,*Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsIn the manuscript titled "EZH2 inhibition sensitizes IDH1R132H mutant gliomas to his-2 tone deacetylase inhibitor" prepared by Sprinzen et al., the author investigated the potential of EZH2 inhibitor as a chemo sensitization approach for IDH1 R132H mutant glioma for HDAC inhibitor treatment. I think the manuscript shows interesting finding of chemo sensitization approach for IDH1 R132H glioma. I have several concerns as follow:
1. The author described an interesting transgenic model, which is established by PDGF-IRES-Cre lentivirus and LSL-Trp53. For clarity, the author may consider including a schematic illustration for the audiences that are not familiar with this strategy. The author may also include the staining of ectopically expressed IDH1 wild type or IDH R132H as an additional histology data.
2. The author used GSEA approach to determine cellular lineages. It might be helpful to provide data describing the expression of lineage-specific genes to confirm the molecular subtype.
3. The author provided coefficient of drug interaction (CDI) data to support the conclusion of drug-drug interaction. The chemo sensitization effect could be better shown by a dose-response curve, e.g., a dose range of HDAC inhibitor with or without EZH2 inhibitor. The LD50 could serve as a strong support for the changes in drug effects.
Comments on the Quality of English LanguageLanguage is fine.
Author Response
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Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsAuthors developed a murine model of proneural IDH1R132H mutated glioma, and found the histone deacetylase inhibitor (HDACi) Panobinostat combination treatment with Tazemetostat is synergistic in both IDH mutant and wildtype models. However, this study lacked mechanism exploration and couldn’t provide solid support for the conclusions. Besides, data statistics required the appropriate statistical methods.
1. Figure 3A 3B, there seemed to be no difference between lane 1 and lane 5, while the statistical results showed p=**.
2. Figure 3A 3B, Panobinostat alone had no effect on the acetylation level of H3K27, indicating that Panobinostat did not play a role under the experimental conditions.
3. Line 238, “IDH1 normally converts isocitrate to α-KG”. But we didn’t see an increase in α-KG in WT group compared with Normal group in S Figure 1D.
4. Line 238, “the R132H mutation changes the enzymatic properties, causing a higher affinity for α-KG rather than isocitrate, thus 239 producing 2HG”. R132H converts α-KG to 2HG, resulting in an increase in 2HG and a decrease in α-KG. But we didn’t see a decrease in α-KG in R132H group in S Figure 1D.
5. Figure 3EF and 4EF, lack of statistical analysis.
6. Figure 3BCD and 4BCD, ANOVA should be used for statistical analysis.
7. Lack of the in vivo animal experimental verification.
8. The figures are not aesthetically pleasing, and font size and layout need to be adjusted.
9. The phenotype research is insufficient and lacks mechanism research.
Comments on the Quality of English LanguageModerate English language editing is required.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
