Package 'oppti'

Title: Outlier Protein and Phosphosite Target Identifier
Description: The aim of oppti is to analyze protein (and phosphosite) expressions to find outlying markers for each sample in the given cohort(s) for the discovery of personalized actionable targets.
Authors: Abdulkadir Elmas
Maintainer: Abdulkadir Elmas <[email protected]>
License: MIT
Version: 1.19.0
Built: 2024-09-30 04:20:45 UTC
Source: https://github.com/bioc/oppti

Help Index


Artificially miss and impute each data entry individually by ignoring outlying values

Description

Infers the normal-state expression of a marker based on its co-expression network, i.e., the weighted average of the marker's nearest neighbors in the data. The returned imputed data will later be used to elucidate dysregulated (protruding) events.

Usage

artImpute(dat, ku = 6, marker.proc.list = NULL, miss.pstat = 0.4,
verbose = FALSE)

Arguments

dat

an object of log2-normalized protein (or gene) expressions, containing markers in rows and samples in columns.

ku

an integer in [1,num.markers], upper bound on the number of nearest neighbors of a marker.

marker.proc.list

character array, the row names of the data to be processed/imputed.

miss.pstat

the score threshold for ignoring potential outliers during imputation. miss.pstat = 1 ignores values outside of the density box (i.e., 1st-3rd quartiles). The algorithm ignores values lying at least (1/miss.pstat)-1 times IQR away from the box; e.g., use miss.pstat=1 to ignore all values lying outside of the box; use miss.pstat=0.4 to ignore values lying at least 1.5 x IQR away from the box; use miss.pstat=0 to employ all data during imputation.

verbose

logical, to show progress of the algorithm.

Value

the imputed data that putatively represents the expressions of the markers in the (matched) normal states.

Examples

dat = setNames(as.data.frame(matrix(1:(5*10),5,10),
row.names = paste('marker',1:5,sep='')), paste('sample',1:10,sep=''))
imputed = artImpute(dat, ku = 2)

Hierarchical cluster analysis

Description

Displays the hierarchically clustered data by the "pheatmap" package. The numbers of clusters along the markers/samples can be set by the user, then the cluster structures are estimated by pair-wise analysis.

Usage

clusterData(data, annotation_row = NULL, annotation_col = NULL,
annotation_colors = NULL, main = NA, legend = TRUE,
clustering_distance_rows = "euclidean",
clustering_distance_cols = "euclidean", display_numbers = FALSE,
number_format = "%.0f", num_clusters_row = NULL,
num_clusters_col = NULL, cluster_rows = TRUE, cluster_cols = TRUE,
border_color = "gray60", annotate_new_clusters_col = FALSE,
zero_white = FALSE, color_low = '#006699', color_mid = 'white',
color_high = 'red',color_palette = NULL, show_rownames = FALSE,
show_colnames = FALSE, min_data = min(data, na.rm = TRUE),
max_data = max(data, na.rm = TRUE),
treeheight_row = ifelse(methods::is(cluster_rows, "hclust") ||
cluster_rows, 50, 0), treeheight_col = ifelse(methods::is(cluster_cols,
"hclust") || cluster_cols, 50, 0))

Arguments

data

an object of log2-normalized protein (or gene) expressions, containing markers in rows and samples in columns.

annotation_row

data frame that specifies the annotations shown on left side of the heat map. Each row defines the features for a specific row. The rows in the data and in the annotation are matched using corresponding row names. Note that color schemes takes into account if variable is continuous or discrete.

annotation_col

similar to annotation_row, but for columns.

annotation_colors

list for specifying annotation_row and annotation_col track colors manually. It is possible to define the colors for only some of the features.

main

character string, an overall title for the plot.

legend

logical, to determine if legend should be drawn or not.

clustering_distance_rows

distance measure used in clustering rows. Possible values are "correlation" for Pearson correlation and all the distances supported by dist, such as "euclidean", etc. If the value is none of the above it is assumed that a distance matrix is provided.

clustering_distance_cols

distance measure used in clustering columns. Possible values the same as for clustering_distance_rows.

display_numbers

logical, determining if the numeric values are also printed to the cells. If this is a matrix (with same dimensions as original matrix), the contents of the matrix are shown instead of original values.

number_format

format strings (C printf style) of the numbers shown in cells. For example "%.2f" shows 2 decimal places and "%.1e" shows exponential notation (see more in sprintf).

num_clusters_row

number of clusters the rows are divided into, based on the hierarchical clustering (using cutree), if rows are not clustered, the argument is ignored.

num_clusters_col

similar to num_clusters_row, but for columns.

cluster_rows

logical, determining if the rows should be clustered; or a hclust object.

cluster_cols

similar to cluster_rows, but for columns.

border_color

color of cell borders on heatmap, use NA if no border should be drawn.

annotate_new_clusters_col

logical, to annotate cluster IDs (column) that will be identified.

zero_white

logical, to display 0 values as white in the colormap.

color_low

color code for the low intensity values in the colormap.

color_mid

color code for the medium intensity values in the colormap.

color_high

color code for the high intensity values in the colormap.

color_palette

vector of colors used in heatmap.

show_rownames

boolean, specifying if row names are be shown.

show_colnames

boolean, specifying if column names are be shown.

min_data

numeric, data value corresponding to minimum intensity in the color_palette

max_data

numeric, data value corresponding to maximum intensity in the color_palette

treeheight_row

the height of a tree for rows, if these are clustered. Default value is 50 points.

treeheight_col

the height of a tree for columns, if these are clustered. Default value is 50 points.

Value

tree, the hierarchical tree structure.

cluster_IDs_row, the (row) cluster identities of the markers.

cluster_IDs_col, the (column) cluster identities of the samples.

Examples

set.seed(1)
dat = setNames(as.data.frame(matrix(runif(10*10),10,10),
row.names = paste('marker',1:10,sep='')), paste('sample',1:10,sep=''))
result = clusterData(dat)

Filter out markers

Description

Filters out markers based on the percentage of missing values, low-expression and low-variability rates.

Usage

dropMarkers(dat, percent_NA = 0.2, low_mean_and_std = 0.05,
q_low_var = 0.25, force_drop = NULL)

Arguments

dat

an object of log2-normalized protein (or gene) expressions, containing markers in rows and samples in columns.

percent_NA

a constant in [0,1], the percentage of missing values that will be tolerated in the filtered data.

low_mean_and_std

a constant in [0,inf], the lower-bound of the mean or standard deviation of a marker in the filtered data.

q_low_var

a constant in [0,1], the quantile of marker variances which serves as a lower-bound of the marker variances in the filtered data.

force_drop

character array containing the marker names that user specifically wants to filter out.

Value

filtered data with the same format as the input data.

the row names (markers) of the data that are filtered out due to low-expression or low-variability.

Examples

dat = setNames(as.data.frame(matrix(1:(5*10),5,10),
row.names = paste('marker',1:5,sep='')), paste('sample',1:10,sep=''))
dat[1,1:2] = NA # marker1 have 20% missing values
dropMarkers(dat, percent_NA = .2) # marker1 is filtered out

Analyze dysregulated (protruding) events

Description

For each marker processed, draws a scatter plot of matching values of observed vs imputed expressions.

Usage

dysReg(dat, dat.imp, marker.proc.list = NULL, verbose = FALSE)

Arguments

dat

an object of log2-normalized protein (or gene) expressions, containing markers in rows and samples in columns.

dat.imp

the imputed data that putatively represents the expressions of the markers in the (matched) normal states.

marker.proc.list

character array, the row names of the data to be processed for dysregulation.

verbose

logical, to show progress of the algorithm

Value

samples' distances to regression line (i.e., dysregulation) on the scatter plots.

the scatter plots.

Examples

dat = setNames(as.data.frame(matrix(1:(5*10),5,10),
row.names = paste('marker',1:5,sep='')), paste('sample',1:10,sep=''))
dat.imp = artImpute(dat, ku=2)
result = dysReg(dat, dat.imp)

Display outlying expressions

Description

Mark outlying expressions on the scatter plot of a given marker

Usage

markOut(dat, dat.imp, dat.imp.test, dat.dys, dys.sig.thr.upp,
marker.proc.list = NULL, dataset = "", num.omit.fit = NULL,
draw.sc = TRUE, draw.vi = TRUE, conf.int = 0.95,
ylab = "Observed", xlab = "Inferred")

Arguments

dat

an object of log2-normalized protein (or gene) expressions, containing markers in rows and samples in columns.

dat.imp

the imputed data that putatively represents the expressions of the markers in the (matched) normal states.

dat.imp.test

marker's p-value of the statistical significance between its observed vs imputed values computed by the Kolmogorov-Smirnov test.

dat.dys

samples' distances to regression line (i.e., dysregulation) on the scatter plots.

dys.sig.thr.upp

the dysregulation score threshold to elucidate/mark significantly dysregulated outlier events.

marker.proc.list

character array, the row names of the data to be processed for outlier analyses and for plotting.

dataset

the cohort name to be used in the output files.

num.omit.fit

number of outlying events to ignore when fitting a marker's observed expressions to the imputed ones.

draw.sc

logical, to draw a scatter plot for every marker in marker.proc.list in a separate PDF file.

draw.vi

logical, to draw a violin plot for every marker in marker.proc.list in a separate PDF file.

conf.int

confidence interval to display around the regression line

ylab

a title for the y axis

xlab

a title for the x axis

Value

the scatter plots of the markers where the outlier dysregulation events are highlighted by red mark.

Examples

set.seed(1)
dat = setNames(as.data.frame(matrix(runif(10*10),10,10),
row.names = paste('marker',1:10,sep='')), paste('sample',1:10,sep=''))
dat.imp = artImpute(dat, ku=6)
dat.imp.test = statTest(dat, dat.imp)[[1]]
dat.dys = dysReg(dat, dat.imp)[[1]]
plots = markOut(dat, dat.imp, dat.imp.test, dat.dys, dys.sig.thr.upp = .25)

Outlier protein and phosphosite target identification

Description

Find outlying markers and events across cancer types.

Usage

oppti(data, mad.norm = FALSE, cohort.names = NULL, panel = "global",
panel.markers = NULL, tol.nas = 20, ku = 6, miss.pstat = 0.4,
demo.panels = FALSE, save.data = FALSE, draw.sc.plots = FALSE,
draw.vi.plots = FALSE, draw.sc.markers = NULL,
draw.ou.plots = FALSE, draw.ou.markers = NULL, verbose = FALSE)

Arguments

data

a list object where each element contains a proteomics data for a different cohort (markers in the rows, samples in the columns) or a character string defining the path to such data (in .RDS format).

mad.norm

logical, to normalize the proteomes to have a unit Median Absolute Deviation.

cohort.names

character array.

panel

a character string describing marker panel, e.g., 'kinases'. Use 'global' to analyze all markers quantified across cohorts (default). Use 'pancan' to analyze the markers commonly quantified across the cohorts.

panel.markers

a character array containing the set of marker names that user wants to analyze, e.g., panel.markers = c("AAK1", "AATK", "ABL1", "ABL2", ...).

tol.nas

a constant in [0,100], tolerance for the percentage of NAs in a marker, e.g., tol.nas = 20 will filter out markers containing 20% or more NAs across samples.

ku

an integer in [1,num.markers], upper bound on the number of nearest neighbors of a marker.

miss.pstat

a constant in [0,1], statistic to estimate potential outliers. See 'artImpute()'.

demo.panels

logical, to draw demographics of the panel in each cohort.

save.data

logical, to save intermediate data (background inference and dysregulation measures).

draw.sc.plots

logical, to draw each marker's qqplot of observed vs inferred (imputed) expressions.

draw.vi.plots

logical, to draw each marker's violin plot of observed vs imputed expressions.

draw.sc.markers

character array, marker list to draw scatter plots

draw.ou.plots

logical, to draw each marker's outlier prevalence (by the percentage of outlying samples) across the cohorts.

draw.ou.markers

character array, marker list to draw pan-cancer outlier percentage plots

verbose

logical, to show progress of the algorithm.

Value

dysregulation scores of every marker for each sample.

the imputed data that putatively represents the expressions of the markers in the (matched) normal states.

the result of Kolmogorov-Smirnov tests that evaluates the statistical significance of each marker's outlier samples.

a data list containing, for each cohort, the percentage of outlier samples for every marker.

a data list containing, for each cohort, the outlier significance threshold.

See Also

[artImpute()] for how to set 'miss.pstat' and 'ku'

Examples

set.seed(1)
dat = setNames(as.data.frame(matrix(runif(10*10),10,10),
row.names = paste('marker',1:10,sep='')), paste('sample',1:10,sep=''))
result = oppti(dat)

Analyze putative outliers

Description

Calculates a statistical measure of each data entry being a putative outlier

Usage

outScores(dat)

Arguments

dat

an object of log2-normalized protein (or gene) expressions, containing markers in rows and samples in columns.

Value

outlier p-statistics

Examples

dat = setNames(as.data.frame(matrix(1:(5*10),5,10),
row.names = paste('marker',1:5,sep='')), paste('sample',1:10,sep=''))
result = outScores(dat)

Draw densities

Description

Draw column densities of an object over multiple plots by using limma::plotDensities() function.

Usage

plotDen(dat, name = "", per.plot = 8, main = NULL, group = NULL,
legend = TRUE)

Arguments

dat

an object of log2-normalized protein (or gene) expressions, containing markers in rows and samples in columns.

name

name tag for the output file.

per.plot

number of densities to be drawn on a single plot. If NULL, ncol(object) will be used.

main

character string, an overall title for the plot.

group

vector or factor classifying the arrays into groups. Should be same length as ncol(object).

legend

character string giving position to place legend. See 'legend' for possible values. Can also be logical, with FALSE meaning no legend.

Value

pdf plot(s).

Examples

dat = setNames(as.data.frame(matrix(1:(5*10),5,10),
row.names = paste('marker',1:5,sep='')), paste('sample',1:10,sep=''))
plotDen(dat, name = 'myresults')

Rank markers by the percentage of outlying events

Description

Ranks markers in the order of decreasing percentage of outlying events.

Usage

rankPerOut(dat.dys, marker.proc.list = NULL, dys.sig.thr.upp)

Arguments

dat.dys

samples' distances to regression line (i.e., dysregulation) on the scatter plots.

marker.proc.list

character array, the row names of the data to be processed for outlier analyses.

dys.sig.thr.upp

the dysregulation score threshold to elucidate/mark significantly dysregulated outlier events.

Value

markers rank-ordered by the percentage of outliers over the samples.

the percentages of outliers corresponding to ranked markers.

Examples

set.seed(1)
dat = setNames(as.data.frame(matrix(runif(10*10),10,10),
row.names = paste('marker',1:10,sep='')), paste('sample',1:10,sep=''))
dat.imp = artImpute(dat, ku=6)
dat.dys = dysReg(dat, dat.imp)[[1]]
result = rankPerOut(dat.dys, dys.sig.thr.upp = .25)

Analyze dysregulation significance

Description

Rank-order markers by the significance of deviation of the observed expressions from the (matched) imputed expressions based on the Kolmogorov-Smirnov (KS) test.

Usage

statTest(dat, dat.imp, marker.proc.list = NULL, pval.insig = 0.2)

Arguments

dat

an object of log2-normalized protein (or gene) expressions, containing markers in rows and samples in columns.

dat.imp

the imputed data that putatively represents the expressions of the markers in the (matched) normal states.

marker.proc.list

character array, the row names of the data to be processed for dysregulation significance.

pval.insig

p-value threshold to determine spurious (null) dysregulation events.

Value

each marker's p-value of the statistical significance between its observed vs imputed values computed by the KS test.

ranked p-values (KS test) of the significant markers, which are lower than pval.insig.

ranked significantly dysregulated markers with p-values lower than pval.insig.

ranked p-values (KS test) of the insignificant markers, which are greater than pval.insig.

ranked insignificantly dysregulated markers (spurious dysregulations) with p-values greater than pval.insig.

Examples

set.seed(1)
dat = setNames(as.data.frame(matrix(runif(10*10),10,10),
row.names = paste('marker',1:10,sep='')), paste('sample',1:10,sep=''))
dat.imp = artImpute(dat, ku=6)
result = statTest(dat, dat.imp) # the dysregulations on marker4 is
# statistically significant with p-value 0.05244755.