--- title: "Example for Classification Data -- Breast Invasive Carcinoma" author: "Marta Lopes and André Veríssimo" date: "`r Sys.Date()`" output: BiocStyle::html_document: number_sections: yes toc: true vignette: > %\VignetteEngine{knitr::rmarkdown} %\VignetteIndexEntry{Example for Classification -- Breast Invasive Carcinoma} %\VignetteEncoding{UTF-8} params: seed: !r 29221 --- ## Instalation ```{r, eval=FALSE} if (!require("BiocManager")) install.packages("BiocManager") BiocManager::install("glmSparseNet") ``` # Required Packages ```{r packages, message=FALSE, warning=FALSE} library(dplyr) library(ggplot2) library(survival) library(loose.rock) library(futile.logger) library(curatedTCGAData) library(TCGAutils) # library(glmSparseNet) # # Some general options for futile.logger the debugging package .Last.value <- flog.layout(layout.format('[~l] ~m')) .Last.value <- loose.rock::show.message(FALSE) # Setting ggplot2 default theme as minimal theme_set(ggplot2::theme_minimal()) ``` # Load data The data is loaded from an online curated dataset downloaded from TCGA using `curatedTCGAData` bioconductor package and processed. To accelerate the process we use a very reduced dataset down to 107 variables only *(genes)*, which is stored as a data object in this package. However, the procedure to obtain the data manually is described in the following chunk. ```{r,include=TRUE,results="hide",message=FALSE,warning=FALSE} brca <- curatedTCGAData(diseaseCode = "BRCA", assays = "RNASeq2GeneNorm", version = "1.1.38", dry.run = FALSE ) ``` ```{r curated_data_non_eval, eval=FALSE} brca <- curatedTCGAData(diseaseCode = "BRCA", assays = "RNASeq2GeneNorm", version = "1.1.38", dry.run = FALSE) ``` ```{r data.show, warning=FALSE, error=FALSE} brca <- TCGAutils::TCGAsplitAssays(brca, c('01','11')) xdata.raw <- t(cbind(assay(brca[[1]]), assay(brca[[2]]))) # Get matches between survival and assay data class.v <- TCGAbiospec(rownames(xdata.raw))$sample_definition %>% factor names(class.v) <- rownames(xdata.raw) # keep features with standard deviation > 0 xdata.raw <- xdata.raw %>% { (apply(., 2, sd) != 0) } %>% { xdata.raw[, .] } %>% scale set.seed(params$seed) small.subset <- c('CD5', 'CSF2RB', 'HSF1', 'IRGC', 'LRRC37A6P', 'NEUROG2', 'NLRC4', 'PDE11A', 'PIK3CB', 'QARS', 'RPGRIP1L', 'SDC1', 'TMEM31', 'YME1L1', 'ZBTB11', sample(colnames(xdata.raw), 100)) xdata <- xdata.raw[, small.subset[small.subset %in% colnames(xdata.raw)]] ydata <- class.v ``` # Fit models Fit model model penalizing by the hubs using the cross-validation function by `cv.glmHub`. ```{r fit.show} fitted <- cv.glmHub(xdata, ydata, family = 'binomial', network = 'correlation', nlambda = 1000, network.options = networkOptions(cutoff = .6, min.degree = .2)) ``` # Results of Cross Validation Shows the results of `1000` different parameters used to find the optimal value in 10-fold cross-validation. The two vertical dotted lines represent the best model and a model with less variables selected *(genes)*, but within a standard error distance from the best. ```{r results} plot(fitted) ``` ## Coefficients of selected model from Cross-Validation Taking the best model described by `lambda.min` ```{r show_coefs} coefs.v <- coef(fitted, s = 'lambda.min')[,1] %>% { .[. != 0]} coefs.v %>% { data.frame(ensembl.id = names(.), gene.name = geneNames(names(.))$external_gene_name, coefficient = ., stringsAsFactors = FALSE) } %>% arrange(gene.name) %>% knitr::kable() ``` ## Hallmarks of Cancer ```{r hallmarks} geneNames(names(coefs.v)) %>% { hallmarks(.$external_gene_name)$heatmap } ``` ## Accuracy ```{r accuracy, echo=FALSE} resp <- predict(fitted, s = 'lambda.min', newx = xdata, type = 'class') flog.info('Misclassified (%d)', sum(ydata != resp)) flog.info(' * False primary solid tumour: %d', sum(resp != ydata & resp == 'Primary Solid Tumor')) flog.info(' * False normal : %d', sum(resp != ydata & resp == 'Solid Tissue Normal')) ``` Histogram of predicted response ```{r predict, echo=FALSE, warning=FALSE} response <- predict(fitted, s = 'lambda.min', newx = xdata, type = 'response') qplot(response, bins = 100) ``` ROC curve ```{r roc, echo=FALSE} roc_obj <- pROC::roc(ydata, as.vector(response)) data.frame(TPR = roc_obj$sensitivities, FPR = 1 - roc_obj$specificities) %>% ggplot() +geom_line(aes(FPR,TPR), color = 2, size = 1, alpha = 0.7)+ labs(title= sprintf("ROC curve (AUC = %f)", pROC::auc(roc_obj)), x = "False Positive Rate (1-Specificity)", y = "True Positive Rate (Sensitivity)") ``` # Session Info ```{r sessionInfo} sessionInfo() ```