Thinking... We need to answer 6 questions about pathway enrichment analysis from the article. We need to read Methods section for "Pathway enrichment analysis" subheading, and look for tool names, versions, gene set libraries, background gene list usage, statistical test used, multiple testing correction. From the Methods text we saw: "Pathway enrichment analysis Functional annotation of differentially expressed genes (DEGs) was performed using DAVID v6.8 (http://david.abcc.ncifcrf.gov/)." Later in the article, they mention: "Pathway enrichment analysis of the identified tumor suppressors and oncogenes revealed suppression of metabolic pathways like fatty acid degradation and amino acid metabolism, and hyperactive cell cycle signaling assisted with aberrant DNA replication and, purine and pyrimidine metabolism as key features of HCC onset and progression (Figs. [238]1 and [239]2)" Also: "Pathway enrichment analysis of identified tumor suppressors and oncogenes revealed suppression of metabolic pathways like fatty acid degradation and amino acid metabolism, and hyperactive cell cycle signaling assisted with aberrant DNA replication and, purine and pyrimidine metabolism as key features of HCC onset and progression (Figs. [238]1 and [239]2)" But we need explicit mention of the enrichment tool, its version, gene set libraries used, background list, statistical test, multiple testing correction. From Methods: "Pathway enrichment analysis Functional annotation of differentially expressed genes (DEGs) was performed using DAVID v6.8 (http://david.abcc.ncifcrf.gov/)." Also: "GSEA" is used for Gene Set Enrichment Analysis of mRNA-GS etc. But for the standard pathway enrichment, the tool is DAVID v6.8. Another mention: "Gene set enrichment plots of HCC patients from [211]GSE62043 (n=100) with low or high mRNA-GS score. Genes down-regulated in tumor compared to non-tumor liver samples from patients with HCC (a) and top 200 marker genes down-regulated in the ‘proliferation’ subclass of HCC; characterized by increased proliferation, high levels of serum AFP, and chromosomal instability, are enriched in HCC patients having high mRNA-GS scores (b) etc." They refer to gene set enrichment plots: maybe GSEA. But they specifically say "Gene set enrichment plots of HCC patients from GSE62043 (n=100) ...". But the method for performing gene set enrichment? It says "Gene set enrichment plots" maybe refers to GSEA. Also they used "MSigDB" gene sets: The figure mentions "Gene set enrichment plots of HCC patients from GSE62043 (n=100) with low or high mRNA-GS score." But the gene sets used: "top 200 marker genes down-regulated in the ‘proliferation’ subclass of HCC; characterized by increased proliferation, high levels of serum AFP, and chromosomal instability" etc. Those are derived from literature. But the methods mention "Gene set enrichment plots" as part of GSEA analysis. They also mention "Gene set enrichment analysis (GSEA)" earlier? Let's search the Methods for GSEA. I saw earlier: "Gene set enrichment analysis (GSEA) was performed by using..." but maybe not. Let's search again in the methods part: The only mention I recall is "Functional annotation of DEGs was performed using DAVID v6.8". That is pathway enrichment. They also mention "Gene set enrichment analysis of HCC patients with low or high mRNA-GS score" which is GSEA. But did they specify that they used GSEA? The text: "Gene set enrichment plots of HCC patients from GSE62043 (n=100) with low or high mRNA-GS score." They might be using GSEA but not explicitly. But in the earlier "Gene set enrichment analysis (GSEA)" maybe they mention the tool. Let's search earlier in Methods: I saw "Gene set enrichment analysis (GSEA) was performed on..." Wait there is a section: "Gene set enrichment analysis (GSEA) was performed using..." Let me read the methods section again carefully. In the Methods, we have the subheading "Pathway enrichment analysis" and they say: "Functional annotation of differentially expressed genes (DEGs) was performed using DAVID v6.8 (http://david.abcc.ncifcrf.gov/)." Then we have other mention: "Gene set enrichment analysis (GSEA) was performed on the mRNA-GS ...". Let's search for "GSEA" in the methods. I see earlier: "Gene set enrichment analysis (GSEA) was performed on HCC patients from GEO dataset GSE15654 (n=216) and TCGA database (n=370) with low or high mRNA-GS score." Wait, that was results. In Methods: I didn't see mention of GSEA as a tool used for enrichment analysis. But maybe they used GSEA for GSEA analysis of mRNA-GS. Let's search for "GSEA" in the methods. I see "Gene set enrichment analysis (GSEA) was performed on HCC patients from GEO dataset GSE15654 (n=216) and TCGA database (n=370) with low or high mRNA-GS score." That appears in the Results section. But the question: "What tool was used for pathway enrichment analysis?: List all tools or software packages used for enrichment analysis that are explicitly mentioned." So the tool used for pathway enrichment of DEGs: DAVID v6.8. Also they used GSEA for gene set enrichment analysis. But GSEA is used for gene set enrichment, not necessarily pathway enrichment, but they want all tools used for enrichment analysis. So both DAVID and GSEA. Are there others? I recall "MSigDB" is a gene set library used. "KEGG", "GO", "Reactome" are used. But the article explicitly states: "Pathway enrichment analysis of the identified tumor suppressors and oncogenes revealed suppression of metabolic pathways" and they refer to figures. They didn't mention which libraries in the methods. Let's search for "KEGG" or "GO" in the article. In the methods part: "Functional annotation of differentially expressed genes (DEGs) was performed using DAVID v6.8 (http://david.abcc.ncifcrf.gov/)." The DAVID tool uses gene ontology (GO) and KEGG as underlying database. But they did not explicitly mention which gene set libraries they used. They might have used the default annotation. But the article does not specify. But we can check the figure captions or supplementary: "Table S1. List of potential tumor suppressors and oncogenes. Left; Tumor suppressors which are downregulated in HCC and whose higher expressions are associated with good survival of HCC patients from TCGA database are listed along with hazard ratio (HR), associated p-value and number of patients (N)." But for pathway enrichment, they used DAVID v6.8. They also used GSEA for gene set enrichment analysis. Are they using gene set libraries? For DAVID, the underlying libraries include GO, KEGG, BioCarta, etc. But did they mention them? I didn't see explicit mention. The article might mention the specific gene set libraries used for GSEA: e.g., MSigDB "C2", "C5" etc. Let's search for "MSigDB". I didn't see. The article may mention "MSigDB" in the results or supplementary. Let's search again: In the methods part, I don't see "MSigDB". In the results, they refer to "top 200 marker genes down-regulated in the 'proliferation' subclass of HCC". This is from some previous study; but not a gene set library. They mention "Gene set enrichment plots of HCC patients from GSE62043" etc. But they didn't specify library. The article might not describe multiple testing correction. They only mention p-value thresholds. They did not mention FDR correction. But we need to confirm if FDR applied. The article says "Not described". They mention "p-value threshold alone is not sufficient." They used "Not described" for FDR. The article used "Not described" for background gene list usage. They might not mention. Let's systematically answer each question: 1. What tool was used for pathway enrichment analysis? The article explicitly mentions "DAVID v6.8" for functional annotation of DEGs. That is the main tool. Also "Gene set enrichment analysis (GSEA)" is used for GSEA. The question: "What tool was used for pathway enrichment analysis?" So we list all tools used for enrichment analysis: "DAVID v6.8" and "GSEA". They also used "Gene set enrichment plots" but not a tool. Therefore list: DAVID, GSEA. 2. Were enrichment tool version(s) described? For DAVID: v6.8. For GSEA: Did they specify version? The article didn't provide a version for GSEA. Let's search: "GSEA" mention may include "GSEA 3.0" or "GSEA v1.0"? I don't see. It only says "Gene set enrichment plots". It doesn't specify version. So GSEA version: Not described. 3. Which gene set libraries were used? For DAVID: It uses GO, KEGG, etc. But not explicitly stated. For GSEA: They mention "MSigDB". But did they? Let's search: "MSigDB" not present. "KEGG" not present. "Reactome" not present. "GO" not present. They may not have explicitly listed gene set libraries. The article may not specify any library. They just mention "Functional annotation of DEGs was performed using DAVID v6.8." DAVID uses gene ontology and KEGG. But not explicitly said. In the article, do they specify "KEGG"? Not described. They may have used default. So answer: Not described. However, maybe they used "MSigDB" gene sets for GSEA. But not indicated. Search for "MSigDB" in the article. I didn't see. So answer: Not described. 4. Does the article describe using a custom or specific background gene list for enrichment analysis? Options: Yes, No, Not described. The article doesn't mention background. So "Not described". 5. What statistical test(s) were used in enrichment analysis? For DAVID, the underlying statistical test is hypergeometric test / Fisher's exact test. But the article does not mention the test. So "Not described". But the question: "State the name(s) of the statistical test(s) used for enrichment analysis (e.g., hypergeometric test, Fisher's exact test). Only include tests linked to enrichment." Since they didn't specify, we answer "Not described". 6. Was multiple testing correction / FDR applied to enrichment analysis? Article explicitly didn't mention. So "Not described". We need output in a table format with columns: "Tool", "Version(s)", "Gene set libraries", "Custom background", "Statistical test(s)", "Multiple testing correction". Let's create the table with one row per tool, maybe combine. But we have two tools: DAVID, GSEA. For DAVID: Version v6.8. Gene set libraries: not described. For GSEA: no version, not described. Gene set libraries: not described. We can put "Not described" for libraries. For custom background: "Not described" for both tools. For statistical test: "Not described". For multiple testing correction: "Not described". Let's fill table accordingly. But the instructions: "If more than one tool, method, or database is used, list all of them separately." So each tool should have its own row. So we will create a table with columns: Tool | Version | Gene Set Libraries | Custom Background | Statistical Test | Multiple Testing Correction Rows: DAVID, GSEA. Now we fill. For DAVID: Version: v6.8. Gene set libraries: Not described. Custom background: Not described. Statistical test: Not described. Multiple testing correction: Not described. For GSEA: Version: Not described. Gene set libraries: Not described. Custom background: Not described. Statistical test: Not described. Multiple testing correction: Not described. But maybe they used "DAVID" which uses hypergeometric test internally; but not mentioned. So "Not described". Ok. Provide table. ...done thinking. | Tool | Version(s) | Gene set libraries | Custom background used? | Statistical test(s) used | Multiple‑testing correction applied? | |------|------------|---------------------|------------------------|---------------------------|--------------------------------------| | DAVID | v6.8 | Not described | Not described | Not described | Not described | | GSEA | Not described | Not described | Not described | Not described | Not described |