Here are the answers to the questions:

1. What tool was used for pathway enrichment analysis?
Not described, but it is mentioned that "9 online databases" were used to predict target genes and subsequently used for GO and pathway enrichment analyses.

2. Was a tool version number provided?
No

3. What gene set library was queried (eg: GO, KEGG, Reactome or other)?
GO (Gene Ontology) and other unspecified pathways (mentioned as "TGF-beta signaling pathway, Wnt signaling pathway, p53 pathway, p38 MAPK pathway, and mTOR signaling pathway")

4. Was a background gene list defined for pathway enrichment analysis?
Not described

5. What statistical test was used for enrichment analysis?
Not described

6. Was false discovery rate correction used to control the number of false positives in the pathway enrichment analysis?
Not described