Package 'cfTools'

Title: Informatics Tools for Cell-Free DNA Study
Description: The cfTools R package provides methods for cell-free DNA (cfDNA) methylation data analysis to facilitate cfDNA-based studies. Given the methylation sequencing data of a cfDNA sample, for each cancer marker or tissue marker, we deconvolve the tumor-derived or tissue-specific reads from all reads falling in the marker region. Our read-based deconvolution algorithm exploits the pervasiveness of DNA methylation for signal enhancement, therefore can sensitively identify a trace amount of tumor-specific or tissue-specific cfDNA in plasma. cfTools provides functions for (1) cancer detection: sensitively detect tumor-derived cfDNA and estimate the tumor-derived cfDNA fraction (tumor burden); (2) tissue deconvolution: infer the tissue type composition and the cfDNA fraction of multiple tissue types for a plasma cfDNA sample. These functions can serve as foundations for more advanced cfDNA-based studies, including cancer diagnosis and disease monitoring.
Authors: Ran Hu [aut, cre] , Mary Louisa Stackpole [aut] , Shuo Li [aut] , Xianghong Jasmine Zhou [aut] , Wenyuan Li [aut]
Maintainer: Ran Hu <[email protected]>
License: file LICENSE
Version: 1.7.0
Built: 2024-12-18 03:11:26 UTC
Source: https://github.com/bioc/cfTools

Help Index


Beta value matrix

Description

A list of methylation levels (e.g., beta values), where each row is a sample and each column is a marker

Usage

data("beta_matrix")

Format

A tibble with 20 rows and 3 variables

marker1

Beta values of marker1 for all samples

marker2

Beta values of marker2 for all samples

marker3

Beta values of marker3 for all samples

Value

A tibble with 20 rows and 3 variables

Author(s)

Ran Hu [email protected]


Cancer Detector

Description

Detect tumor-derived cfDNA and estimate the tumor burden.

Usage

CancerDetector(
  readsBinningFile,
  tissueMarkersFile,
  lambda = 0.5,
  id = "sample"
)

Arguments

readsBinningFile

a file of the fragment-level methylation states of reads that mapped to the markers.

tissueMarkersFile

a file of paired shape parameters of beta distributions for markers.

lambda

a number controlling "confounding" markers' distance from average markers.

id

the sample ID.

Value

a list containing the cfDNA tumor burden and the normal cfDNA fraction.

Examples

## input files
demo.dir <- system.file("data", package="cfTools")
readsBinningFile <- file.path(demo.dir, "CancerDetector.reads.txt.gz")
tissueMarkersFile <- file.path(demo.dir, "CancerDetector.markers.txt.gz")
lambda <- 0.5
id <- "test"

CancerDetector(readsBinningFile, tissueMarkersFile, lambda, id)

Cancer-specific marker parameter

Description

The paired shape parameters of beta distributions for cancer-specific markers

Usage

data("CancerDetector.markers")

Format

A tibble with 1266 rows and 3 variables

markerName

Name of the marker

tumor

Paired beta distribution shape parameters for tumor samples

normalPlasma

Paired beta distribution shape parameters for normal plasma samples

Value

A tibble with 1266 rows and 3 variables

Author(s)

Ran Hu [email protected]


Fragment-level methylation state for cancer detection

Description

The fragment-level methylation states of reads that mapped to the cancer-specific markers

Usage

data("CancerDetector.reads")

Format

A tibble with 9991 rows and 2 variables

markerName

Name of the marker

methState

Fragment-level methylation states, which are represented by a sequence of binary values (0 represents unmethylated CpG and 1 represents methylated CpG on the same fragment)

Value

A tibble with 9991 rows and 2 variables

Author(s)

Ran Hu [email protected]


cfDNA methylation read deconvolution

Description

Infer the tissue-type composition of plasma cfDNA.

Usage

cfDeconvolve(
  readsBinningFile,
  tissueMarkersFile,
  numTissues,
  emAlgorithmType = "em.global.unknown",
  likelihoodRatioThreshold = 2,
  emMaxIterations = 100,
  randomSeed = 0,
  id = "sample"
)

Arguments

readsBinningFile

a file of the fragment-level methylation states of reads that mapped to the markers. Either in plain text or compressed form.

tissueMarkersFile

a file of paired shape parameters of beta distributions for markers.

numTissues

a number of tissue types.

emAlgorithmType

a read-based tissue deconvolution EM algorithm type: em.global.unknown (default), em.global.known, em.local.unknown, em.local.known.

likelihoodRatioThreshold

a positive float number. Default is 2.

emMaxIterations

a number of EM algorithm maximum iteration. Default is 100.

randomSeed

a random seed that initialize the EM algorithm. Default is 0.

id

the sample ID.

Value

a list containing the cfDNA fractions of different tissue types and an unknown class.

Examples

## input files
demo.dir <- system.file("data", package="cfTools")
readsBinningFile <- file.path(demo.dir, "cfDeconvolve.reads.txt.gz")
tissueMarkersFile <- file.path(demo.dir, "cfDeconvolve.markers.txt.gz")
numTissues <- 7
emAlgorithmType <- "em.global.unknown"
likelihoodRatioThreshold <- 2
emMaxIterations <- 100
randomSeed <- 0
id <- "test"

cfDeconvolve(readsBinningFile, tissueMarkersFile, numTissues, 
emAlgorithmType, likelihoodRatioThreshold, emMaxIterations, randomSeed, id)

Tissue-specific marker parameter

Description

The paired shape parameters of beta distributions for tissue-specific markers

Usage

data("cfDeconvolve.markers")

Format

A tibble with 10 rows and 8 variables

markerName

Name of the marker

tissue1

Paired beta distribution shape parameters for tissue1 samples

tissue2

Paired beta distribution shape parameters for tissue2 samples

tissue3

Paired beta distribution shape parameters for tissue3 samples

tissue4

Paired beta distribution shape parameters for tissue4 samples

tissue5

Paired beta distribution shape parameters for tissue5 samples

tissue6

Paired beta distribution shape parameters for tissue6 samples

tissue7

Paired beta distribution shape parameters for tissue7 samples

Value

A tibble with 10 rows and 8 variables

Author(s)

Ran Hu [email protected]


Fragment-level methylation state for tissue deconvolution

Description

The fragment-level methylation states of reads that mapped to the tissue-specific markers

Usage

data("cfDeconvolve.reads")

Format

A tibble with 942 rows and 2 variables

markerName

Name of the marker

methState

Fragment-level methylation states, which are represented by a sequence of binary values (0 represents unmethylated CpG and 1 represents methylated CpG on the same fragment)

Value

A tibble with 942 rows and 2 variables

Author(s)

Ran Hu [email protected]


cfSort: tissue deconvolution

Description

Tissue deconvolution in cfDNA using DNN models.

Usage

cfSort(readsBinningFile, id = "sample")

Arguments

readsBinningFile

a file of the fragment-level methylation states of reads that mapped to the cfSort markers. In compressed form.

id

the sample ID.

Value

the tissue composition of the cfDNA sample.

Examples

## input files
demo.dir <- system.file("data", package="cfTools")
readsBinningFile <- file.path(demo.dir, "cfsort_reads.txt.gz")
id <- "test"

cfSort(readsBinningFile, id)

cfSort markers

Description

Marker information for the cfSort function, where each row is the information about a marker

Usage

data("cfsort_markers")

Format

A tibble with 51035 rows and 4 variables

marker_index

The marker index used in cfSort method

alpha_threshold

The alpha threshold for each marker

pair

The pair of tissues used for identifying the marker

group

The group number for each marker

Value

A tibble with 51035 rows and 4 variables

Author(s)

Ran Hu [email protected]


Fragment-level methylation state for cfSort tissue deconvolution

Description

The fragment-level methylation states of reads that mapped to the cfSort markers

Usage

data("cfsort_reads")

Format

A tibble with 99999 rows and 2 variables

markerName

Name of the cfSort marker

methState

Fragment-level methylation states, which are represented by a sequence of binary values (0 represents unmethylated CpG and 1 represents methylated CpG on the same fragment)

Value

A tibble with 99999 rows and 2 variables

Author(s)

Ran Hu [email protected]


Methylation information for CpG on the original bottom strand (OB)

Description

Methylation information for CpG on the original bottom strand (OB), which is one of the outputs from 'bismark methylation extractor'

Usage

data("CpG_OB_demo")

Format

A tibble with 2224 rows and 5 variables

sequence ID

ID of the sequence

methylation state

Methylated or unmethylated CpG site

chromosome name

Chromosome name

chromosome start

Chromosome start position

methylation call

Methylation call

Value

A tibble with 2224 rows and 5 variables

Author(s)

Ran Hu [email protected]


Methylation information for CpG on the original top strand (OT)

Description

Methylation information for CpG on the original top strand (OT), which is one of the outputs from 'bismark methylation extractor'

Usage

data("CpG_OT_demo")

Format

A tibble with 2556 rows and 5 variables

sequence ID

ID of the sequence

methylation state

Methylated or unmethylated CpG site

chromosome name

Chromosome name

chromosome start

Chromosome start position

methylation call

Methylation call

Value

A tibble with 2556 rows and 5 variables

Author(s)

Ran Hu [email protected]


Fragment-level methylation information

Description

A BED file of fragment-level methylation information

Usage

data("demo.fragment_level.meth.bed")

Format

A tibble with 552 rows and 9 variables

chr

Chromosome

start

Chromosome start

end

Chromosome end

name

ID of the sequence

fragmentLength

Fragment length

strand

Strand

cpgNumber

Number of CpG sites on the fragment

cpgPosition

Postions of CpG sites on the fragment

methState

A string of methylation states of CpG sites on the fragment

Value

A tibble with 552 rows and 9 variables

Author(s)

Ran Hu [email protected]


Fragment-level information

Description

A BED file of fragment-level information

Usage

data("demo.refo_frag.bed")

Format

A tibble with 559 rows and 6 variables

chr

Chromosome

start

Chromosome start

end

Chromosome end

fragmentLength

Fragment length

strand

Strand

name

ID of the sequence

Value

A tibble with 559 rows and 6 variables

Author(s)

Ran Hu [email protected]


Methylation information on fragments

Description

A BED file of methylation information on fragments

Usage

data("demo.refo_meth.bed")

Format

A tibble with 552 rows and 8 variables

chr

Chromosome

cpgStart

Start postion of first CpG on the fragment

cpgEnd

End postion of first CpG on the fragment

strand

Strand

cpgNumber

Number of CpG sites on the fragment

cpgPosition

Postions of CpG sites on the fragment

methState

A string of methylation states of CpG sites on the fragment

name

ID of the sequence

Value

A tibble with 552 rows and 8 variables

Author(s)

Ran Hu [email protected]


Paired-end sequencing reads

Description

Paired-end sequencing reads information

Usage

data("demo.sorted.bed")

Format

A tibble with 1117 rows and 6 variables

chr

Chromosome name

start

Chromosome start

end

Chromosome end

name

Sequence ID

score

Mapping quality score

strand

Strand

Value

A tibble with 1117 rows and 6 variables

Author(s)

Ran Hu [email protected]


Generate fragment-level information about methylation states

Description

Join two lists containing the fragment information and the methylation states on each fragment into one list.

Usage

GenerateFragMeth(frag_bed, meth_bed, output.dir = "", id = "")

Arguments

frag_bed

a BED file containing information for every fragment, which is the output of MergePEReads().

meth_bed

a BED file containing methylation states on every fragment, which is the output of MergeCpGs().

output.dir

a path to the output directory. Default is "", which means the output will not be written into a file.

id

an ID name for the input data. Default is "", which means the output will not be written into a file.

Value

a list in BED file format and/or written to an output BED file.

Examples

## input files
demo.dir <- system.file("data", package="cfTools")
frag_bed <- read.delim(file.path(demo.dir, "demo.refo_frag.bed.txt.gz"), 
colClasses = "character")
meth_bed <- read.delim(file.path(demo.dir, "demo.refo_meth.bed.txt.gz"), 
colClasses = "character")

output <- GenerateFragMeth(frag_bed, meth_bed)

Generate the methylation pattern of markers

Description

Output paired shape parameters of beta distributions for methylation markers.

Usage

GenerateMarkerParam(x, sample.types, marker.names, output.file = "")

Arguments

x

a list of methylation levels (e.g., beta values), where each row is a sample and each column is a marker.

sample.types

a vector of sample types (e.g., tumor or normal, tissue types) corresponding to the rows of the list.

marker.names

a vector of marker names corresponding to the columns of the list.

output.file

a character string naming the output file. Default is "", which means the output will not be written into a file.

Value

a list containing the paired shape parameters of beta distributions for markers and/or written to an output file.

Examples

## input files
demo.dir <- system.file("data", package="cfTools")
methLevel <- read.table(file.path(demo.dir, "beta_matrix.txt.gz"), 
row.names=1, header = TRUE)
sampleTypes <- read.table(file.path(demo.dir, "sample_type.txt.gz"), 
row.names=1, header = TRUE)$sampleType
markerNames <- read.table(file.path(demo.dir, "marker_index.txt.gz"), 
row.names=1, header = TRUE)$markerIndex

output <- GenerateMarkerParam(methLevel, sampleTypes, markerNames)

Marker name

Description

A vector of marker names corresponding to the columns of the list of methylation levels.

Usage

data("marker_index")

Format

A tibble with 3 rows and 1 variables

markerIndex

Marker name

Value

A tibble with 3 rows and 1 variables

Author(s)

Ran Hu [email protected]


Genomic postions of markers

Description

A BED file of genomic regions of markers

Usage

data("markers.bed")

Format

A tibble with 3 rows and 4 variables

chr

Chromosome

start

Chromosome start

end

Chromosome end

markerName

Marker name

Value

A tibble with 3 rows and 4 variables

Author(s)

Ran Hu [email protected]


Generate fragment-level methylation states of CpGs

Description

Merge the methylation states of all CpGs corresponding to the same fragment onto one line in output.

Usage

MergeCpGs(CpG_OT, CpG_OB, output.dir = "", id = "")

Arguments

CpG_OT

a file of methylation information for CpG on the original top strand (OT), which is one of the outputs from 'bismark methylation extractor'.

CpG_OB

a file of methylation information for CpG on the original bottom strand (OB), which is one of the outputs from 'bismark methylation extractor'.

output.dir

a path to the output directory. Default is "", which means the output will not be written into a file.

id

an ID name for the input data. Default is "", which means the output will not be written into a file.

Value

a list in BED file format and/or written to an output BED file.

Examples

## input files
demo.dir <- system.file("data", package="cfTools")
CpG_OT <- file.path(demo.dir, "CpG_OT_demo.txt.gz")
CpG_OB <- file.path(demo.dir, "CpG_OB_demo.txt.gz")

output <- MergeCpGs(CpG_OT, CpG_OB)

Generate fragment-level information for paired-end sequencing reads

Description

Merge BED file (the output of 'bedtools bamtobed') to fragment-level for paired-end sequencing reads.

Usage

MergePEReads(bed_file, output.dir = "", id = "")

Arguments

bed_file

a (sorted) BED file of paired-end reads.

output.dir

a path to the output directory. Default is "", which means the output will not be written into a file.

id

an ID name for the input data. Default is "", which means the output will not be written into a file.

Value

a list in BED file format and/or written to an output BED file.

Examples

## input files
demo.dir <- system.file("data", package="cfTools")
PEReads <- file.path(demo.dir, "demo.sorted.bed.txt.gz")

output <- MergePEReads(PEReads)

Sample type

Description

A vector of sample types (e.g., tumor or normal, tissue types) corresponding to the rows of the list of methylation levels.

Usage

data("sample_type")

Format

A tibble with 20 rows and 1 variables

sampleType

Sample type

Value

A tibble with 20 rows and 1 variables

Author(s)

Ran Hu [email protected]