Table 2.
Summary of studies evaluating the association of genetic variants and changes in gene expression with response to anti-VEGF therapies in diabetic macular edema.
| Gene and variants | Anti-VEGF drug | DM type | Response criteria | Cohort size | Follow-up (months) | p value | Country | Reference |
|---|---|---|---|---|---|---|---|---|
|
VEGFA
-634C>G (rs2010963) |
Bevacizumab | T2 | Non-responder: increase in VA < 3 lines AND <50% decrease in CMT Responder: increase in VA ≥ 3 lines AND ≥50% decrease in CMT |
64 DME Responder = 36eyes (24 patients) Non − responder = 68eyes (40 patients) |
9-12 | p < 0.001 | Egypt | Shazly et al. [40] |
|
VEGFA
rs2010963 rs2146323 rs10434 rs833069 rs6921438 |
Ranibizumab | NA | Non-responder: increase in VA < 2 lines AND CMT > 300 microns Responder: increase in VA ≥ 2 lines AND CMT ≤ 300microns |
95 DME Responder = 53 Non − responder = 42 |
5 | p > 0.05 for all variants | Turkey | Tetikoğlu et al. [85] |
| Transcriptome-wide gene expression analysis1 | Bevacizumab | T2 | Non-responder: stable/worsening/<10% reduction in CMT Responder: >10% reduction in CMT |
Responder = 5 Non − responder = 5 |
NA | 35 genes upregulated 26 genes downregulated |
India | Dabir et al. [86] |
| Expression of multiple lncRNA genes2 | Aflibercept | T2 | Not defined | 75 DME Responder = 51 Non − responder = 9 (missingdata = 15) |
1 | p > 0.05 for all lncRNAs | Egypt | Toraih et al. [87] |
Study evaluated mRNA expression in peripheral whole blood following bevacizumab treatment. Study evaluated serum levels of hyperglycaemia sensitive long non-coding RNA following aflibercept treatment. DM: diabetes mellitus; NA: not available; DME: diabetic macular edema; VA: visual acuity; CMT: central macular thickness; VEGFA: vascular endothelial growth factor A; lncRNA: long non-coding ribo-nucleic acid.