Contents

1 Introduction

This package is designed for reactome pathway-based analysis. Reactome is an open-source, open access, manually curated and peer-reviewed pathway database.

2 Citation

If you use ReactomePA1 in published research, please cite:

G Yu, QY He*. ReactomePA: an R/Bioconductor package for reactome pathway analysis and visualization. Molecular BioSystems 2016, 12(2):477-479. doi:[10.1039/C5MB00663E](http://dx.doi.org/10.1039/C5MB00663E)

3 Supported organisms

Currently ReactomePA supports several model organisms, including ‘celegans’, ‘fly’, ‘human’, ‘mouse’, ‘rat’, ‘yeast’ and ‘zebrafish’. The input gene ID should be Entrez gene ID. We recommend using clusterProfiler::bitr to convert biological IDs. For more detail, please refer to bitr: Biological Id TranslatoR.

4 Pathway Enrichment Analysis

Enrichment analysis is a widely used approach to identify biological themes. Here, we implement hypergeometric model to assess whether the number of selected genes associated with reactome pathway is larger than expected. The p values were calculated based the hypergeometric model2.

library(ReactomePA)
data(geneList)
de <- names(geneList)[abs(geneList) > 1.5]
head(de)
## [1] "4312"  "8318"  "10874" "55143" "55388" "991"
x <- enrichPathway(gene=de,pvalueCutoff=0.05, readable=T)
head(as.data.frame(x))
##                          ID
## R-HSA-69620     R-HSA-69620
## R-HSA-2500257 R-HSA-2500257
## R-HSA-141424   R-HSA-141424
## R-HSA-141444   R-HSA-141444
## R-HSA-69618     R-HSA-69618
## R-HSA-68877     R-HSA-68877
##                                                                                        Description
## R-HSA-69620                                                                 Cell Cycle Checkpoints
## R-HSA-2500257                                              Resolution of Sister Chromatid Cohesion
## R-HSA-141424                                         Amplification of signal from the kinetochores
## R-HSA-141444  Amplification  of signal from unattached  kinetochores via a MAD2  inhibitory signal
## R-HSA-69618                                                             Mitotic Spindle Checkpoint
## R-HSA-68877                                                                   Mitotic Prometaphase
##               GeneRatio   BgRatio       pvalue     p.adjust       qvalue
## R-HSA-69620      37/317 293/10513 9.088780e-14 6.343968e-11 5.491536e-11
## R-HSA-2500257    23/317 127/10513 3.172506e-12 1.005875e-09 8.707168e-10
## R-HSA-141424     20/317  96/10513 5.764327e-12 1.005875e-09 8.707168e-10
## R-HSA-141444     20/317  96/10513 5.764327e-12 1.005875e-09 8.707168e-10
## R-HSA-69618      21/317 112/10513 1.433433e-11 2.001072e-09 1.732190e-09
## R-HSA-68877      26/317 200/10513 2.793891e-10 3.250226e-08 2.813497e-08
##                                                                                                                                                                                                                                 geneID
## R-HSA-69620   CDC45/CDCA8/MCM10/CDC20/CENPE/CCNB2/NDC80/UBE2C/SKA1/CENPM/CENPN/CCNA2/CDK1/ERCC6L/MAD2L1/KIF18A/BIRC5/AURKB/CHEK1/CCNB1/MCM5/MCM2/KIF2C/CDC25A/CDC6/PLK1/BUB1B/GTSE1/EXO1/ZWINT/CENPU/SPC25/CENPI/CCNE1/ORC6/ORC1/TAOK1
## R-HSA-2500257                                                                                CDCA8/CDC20/CENPE/CCNB2/NDC80/SKA1/CENPM/CENPN/CDK1/ERCC6L/MAD2L1/KIF18A/BIRC5/AURKB/CCNB1/KIF2C/PLK1/BUB1B/ZWINT/CENPU/SPC25/CENPI/TAOK1
## R-HSA-141424                                                                                                  CDCA8/CDC20/CENPE/NDC80/SKA1/CENPM/CENPN/ERCC6L/MAD2L1/KIF18A/BIRC5/AURKB/KIF2C/PLK1/BUB1B/ZWINT/CENPU/SPC25/CENPI/TAOK1
## R-HSA-141444                                                                                                  CDCA8/CDC20/CENPE/NDC80/SKA1/CENPM/CENPN/ERCC6L/MAD2L1/KIF18A/BIRC5/AURKB/KIF2C/PLK1/BUB1B/ZWINT/CENPU/SPC25/CENPI/TAOK1
## R-HSA-69618                                                                                             CDCA8/CDC20/CENPE/NDC80/UBE2C/SKA1/CENPM/CENPN/ERCC6L/MAD2L1/KIF18A/BIRC5/AURKB/KIF2C/PLK1/BUB1B/ZWINT/CENPU/SPC25/CENPI/TAOK1
## R-HSA-68877                                                                 CDCA8/CDC20/CENPE/CCNB2/NDC80/NCAPH/SKA1/NEK2/CENPM/CENPN/CDK1/ERCC6L/MAD2L1/KIF18A/BIRC5/NCAPG/AURKB/CCNB1/KIF2C/PLK1/BUB1B/ZWINT/CENPU/SPC25/CENPI/TAOK1
##               Count
## R-HSA-69620      37
## R-HSA-2500257    23
## R-HSA-141424     20
## R-HSA-141444     20
## R-HSA-69618      21
## R-HSA-68877      26

For calculation/parameter details, please refer to the vignette of DOSE3..

4.1 Pathway analysis of NGS data

Pathway analysis using NGS data (eg, RNA-Seq and ChIP-Seq) can be performed by linking coding and non-coding regions to coding genes via ChIPseeker package, which can annotates genomic regions to their nearest genes, host genes, and flanking genes respectivly. In addtion, it provides a function, seq2gene, that simultaneously considering host genes, promoter region and flanking gene from intergenic region that may under control via cis-regulation. This function maps genomic regions to genes in a many-to-many manner and facilitate functional analysis. For more details, please refer to ChIPseeker4.

4.2 Visualize enrichment result

We implement barplot, dotplot enrichment map and category-gene-network for visualization. It is very common to visualize the enrichment result in bar or pie chart. We believe the pie chart is misleading and only provide bar chart.

barplot(x, showCategory=8)

dotplot(x, showCategory=15)

Enrichment map can be viusalized by enrichMap:

enrichMap(x, layout=igraph::layout.kamada.kawai, vertex.label.cex = 1)

In order to consider the potentially biological complexities in which a gene may belong to multiple annotation categories, we developed cnetplot function to extract the complex association between genes and diseases.

cnetplot(x, categorySize="pvalue", foldChange=geneList)

4.3 Comparing enriched reactome pathways among gene clusters with clusterProfiler

We have developed an R package clusterProfiler5 for comparing biological themes among gene clusters. ReactomePA works fine with clusterProfiler and can compare biological themes at reactome pathway perspective.

require(clusterProfiler)
data(gcSample)
res <- compareCluster(gcSample, fun="enrichPathway")
plot(res)

5 Gene Set Enrichment Analysis

A common approach in analyzing gene expression profiles was identifying differential expressed genes that are deemed interesting. The enrichPathway function we demonstrated previously were based on these differential expressed genes. This approach will find genes where the difference is large, but it will not detect a situation where the difference is small, but evidenced in coordinated way in a set of related genes. Gene Set Enrichment Analysis (GSEA)6 directly addressed this limitation. All genes can be used in GSEA; GSEA aggregates the per gene statistics across genes within a gene set, therefore making it possible to detect situations where all genes in a predefined set change in a small but coordinated way. For algorithm details, please refer to the vignette of DOSE3.

y <- gsePathway(geneList, nPerm=1000,
                minGSSize=120, pvalueCutoff=0.2,
                pAdjustMethod="BH", verbose=FALSE)
res <- as.data.frame(y)
head(res)
##                          ID                                    Description
## R-HSA-9006934 R-HSA-9006934         Signaling by Receptor Tyrosine Kinases
## R-HSA-1474244 R-HSA-1474244              Extracellular matrix organization
## R-HSA-211859   R-HSA-211859                          Biological oxidations
## R-HSA-1474228 R-HSA-1474228        Degradation of the extracellular matrix
## R-HSA-6811442 R-HSA-6811442 Intra-Golgi and retrograde Golgi-to-ER traffic
## R-HSA-2467813 R-HSA-2467813                Separation of Sister Chromatids
##               setSize enrichmentScore       NES      pvalue  p.adjust
## R-HSA-9006934     466      -0.3269981 -1.453592 0.001216545 0.0112782
## R-HSA-1474244     265      -0.4590060 -1.933696 0.001355014 0.0112782
## R-HSA-211859      166      -0.3726000 -1.487565 0.002954210 0.0112782
## R-HSA-1474228     120      -0.4171865 -1.604350 0.002962963 0.0112782
## R-HSA-6811442     163       0.3379484  1.480716 0.003021148 0.0112782
## R-HSA-2467813     161       0.6363838  2.772837 0.003058104 0.0112782
##                   qvalues rank                   leading_edge
## R-HSA-9006934 0.005276349 2788 tags=26%, list=22%, signal=21%
## R-HSA-1474244 0.005276349 1943 tags=34%, list=16%, signal=29%
## R-HSA-211859  0.005276349 2129 tags=25%, list=17%, signal=21%
## R-HSA-1474228 0.005276349 1943 tags=35%, list=16%, signal=30%
## R-HSA-6811442 0.005276349  205    tags=7%, list=2%, signal=7%
## R-HSA-2467813 0.005276349 1768 tags=37%, list=14%, signal=32%
##                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    core_enrichment
## R-HSA-9006934 26052/534/2065/9459/3709/7423/1215/2263/83464/26469/7057/4670/7072/23263/1298/3915/5921/5441/200734/9846/9611/3315/466/11140/5595/5228/7424/1499/64759/6453/2252/55914/7059/26084/8660/23767/8038/5295/6778/2962/3910/3082/1291/29/10253/3791/1301/3643/6776/558/5590/3685/9252/1280/4804/3675/2261/11059/26999/9639/2246/4734/4803/10252/3912/1793/4208/6196/1278/8829/50650/1003/5753/1277/23365/2241/1293/2247/1848/1281/55701/50509/1290/9365/7058/25759/56034/4254/26018/2099/3480/6387/5159/857/1289/1292/3908/3909/8817/4915/5125/3249/4485/3551/3730/9828/3913/5327/3667/1287/7060/3479/10451/1846/80310/3708/8483/2066/5241
## R-HSA-1474244                                                                                                                                                                  8038/11132/4017/1288/4811/3910/3371/1291/3791/831/1301/4238/7450/3685/80781/1280/1306/4314/3675/8425/977/4054/7837/7042/3912/4322/1278/1511/4060/30008/1277/164656/22795/10516/81578/1293/2247/1295/58494/8076/5118/2192/1281/83700/50509/4319/1290/1513/11096/2202/4313/2199/3693/10536/1294/11117/3339/1462/1289/1292/3908/4016/3909/4053/6678/1296/633/5654/2331/63923/7043/3913/1300/2200/1634/7177/1287/3679/4680/2006/7373/1307/1311/1308/652/4148/54829/4239
## R-HSA-211859                                                                                                                                                                                                                                                                                                                                                                                                                            4837/6799/1553/8459/284541/7366/8648/1543/2098/29104/1548/54996/27306/196/2232/2954/57834/6817/22977/1581/7358/216/1592/2948/126/2946/2944/54988/1589/8639/2953/2952/4128/66002/2947/4129/125/11283/1580/9
## R-HSA-1474228                                                                                                                                                                                                                                                                                                                                                                                                                    11132/1288/4811/1291/831/1301/80781/1280/1306/4314/3912/4322/1278/1511/1277/164656/1293/1295/1281/50509/4319/1290/1513/11096/4313/1294/3339/1289/1292/3909/1296/5654/1300/2200/1634/7177/1287/2006/7373/1307/1308
## R-HSA-6811442                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       9493/1062/81930/3832/3833/146909/10112/24137/11004/29127/56992
## R-HSA-2467813                                                                                                                                                                                                                                                                                                      55143/991/1062/10403/11065/220134/79019/55839/54821/4085/81930/332/9212/9232/11004/5347/701/11130/79682/57405/2491/9700/1058/699/1063/5688/5709/55055/5698/5693/7277/5713/79980/9735/5721/5691/5685/84790/5690/5684/5885/5686/5695/10213/23198/10381/7979/54908/6396/10383/5699/5714/10376/5702/5905/3619/5708/55166/5692/10393

5.1 Visualize GSEA result

enrichMap(y)
gseaplot(y, geneSetID = "R-HSA-69242")

6 Pathway Visualization

In ReactomePA, we also implemented viewPathway to visualized the pathway.

viewPathway("E2F mediated regulation of DNA replication", readable=TRUE, foldChange=geneList)

More documents can be found on the project website, https://guangchuangyu.github.io/ReactomePA.

7 Session Information

Here is the output of sessionInfo() on the system on which this document was compiled:

## R version 3.4.2 (2017-09-28)
## Platform: x86_64-pc-linux-gnu (64-bit)
## Running under: Ubuntu 16.04.3 LTS
## 
## Matrix products: default
## BLAS: /home/biocbuild/bbs-3.6-bioc/R/lib/libRblas.so
## LAPACK: /home/biocbuild/bbs-3.6-bioc/R/lib/libRlapack.so
## 
## locale:
##  [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C              
##  [3] LC_TIME=en_US.UTF-8        LC_COLLATE=C              
##  [5] LC_MONETARY=en_US.UTF-8    LC_MESSAGES=en_US.UTF-8   
##  [7] LC_PAPER=en_US.UTF-8       LC_NAME=C                 
##  [9] LC_ADDRESS=C               LC_TELEPHONE=C            
## [11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C       
## 
## attached base packages:
## [1] parallel  stats4    stats     graphics  grDevices utils     datasets 
## [8] methods   base     
## 
## other attached packages:
## [1] ReactomePA_1.22.0    DOSE_3.4.0           org.Hs.eg.db_3.4.2  
## [4] AnnotationDbi_1.40.0 IRanges_2.12.0       S4Vectors_0.16.0    
## [7] Biobase_2.38.0       BiocGenerics_0.24.0  BiocStyle_2.6.0     
## 
## loaded via a namespace (and not attached):
##  [1] qvalue_2.10.0       fgsea_1.4.0         reshape2_1.4.2     
##  [4] splines_3.4.2       colorspace_1.3-2    graphite_1.24.0    
##  [7] htmltools_0.3.6     yaml_2.1.14         blob_1.1.0         
## [10] rlang_0.1.2         DBI_0.7             BiocParallel_1.12.0
## [13] rappdirs_0.3.1      bit64_0.9-7         rvcheck_0.0.9      
## [16] plyr_1.8.4          stringr_1.2.0       munsell_0.4.3      
## [19] GOSemSim_2.4.0      gtable_0.2.0        memoise_1.1.0      
## [22] evaluate_0.10.1     labeling_0.3        knitr_1.17         
## [25] Rcpp_0.12.13        reactome.db_1.62.0  backports_1.1.1    
## [28] scales_0.5.0        checkmate_1.8.5     DO.db_2.9          
## [31] graph_1.56.0        bit_1.1-12          gridExtra_2.3      
## [34] fastmatch_1.1-0     ggplot2_2.2.1       digest_0.6.12      
## [37] stringi_1.1.5       bookdown_0.5        rprojroot_1.2      
## [40] grid_3.4.2          tools_3.4.2         magrittr_1.5       
## [43] lazyeval_0.2.1      tibble_1.3.4        RSQLite_2.0        
## [46] GO.db_3.4.2         pkgconfig_2.0.1     data.table_1.10.4-3
## [49] rmarkdown_1.6       httr_1.3.1          R6_2.2.2           
## [52] igraph_1.1.2        compiler_3.4.2

References

1. Yu, G. & He, Q.-Y. ReactomePA: An r/bioconductor package for reactome pathway analysis and visualization. Mol. BioSyst. 12, 477–479 (2016).

2. Boyle, E. I. et al. GO::TermFinder–open source software for accessing gene ontology information and finding significantly enriched gene ontology terms associated with a list of genes. Bioinformatics (Oxford, England) 20, 3710–3715 (2004).

3. Yu, G., Wang, L.-G., Yan, G.-R. & He, Q.-Y. DOSE: An r/bioconductor package for disease ontology semantic and enrichment analysis. Bioinformatics 31, 608–609 (2015).

4. Yu, G., Wang, L.-G. & He, Q.-Y. ChIPseeker: An r/bioconductor package for chip peak annotation, comparison and visualization. Bioinformatics 31, 2382–2383 (2015).

5. Yu, G., Wang, L.-G., Han, Y. & He, Q.-Y. clusterProfiler: an r package for comparing biological themes among gene clusters. OMICS: A Journal of Integrative Biology 16, 284–287 (2012).

6. Subramanian, A. et al. Gene set enrichment analysis: A knowledge-based approach for interpreting genome-wide expression profiles. Proceedings of the National Academy of Sciences of the United States of America 102, 15545–15550 (2005).