Rectum Adenocarcinoma: Correlations between copy number and mRNA expression
Maintained by John Zhang (MD Anderson Cancer Center)
Overview
Introduction

A TCGA sample is profiled to detect the copy number variations and expressions of genes. This pipeline attempts to correlate copy number and expression data of genes across samples to determine if the copy number variations also result in differential expressions. This report contains the calculated correlation coefficients based on measurements of genomic copy number (log2) values and intensity of the expressions of the corresponding feature across patients. High positive/low negative correlation coefficients indicate that genomic alterations result in differences in the expressions of mRNA the genomic regions transcribe.

Summary

The correlation coefficients in 10, 20, 30, 40, 50, 60, 70, 80, 90 percentiles are -0.06358, 0.0159, 0.0839, 0.1504, 0.2189, 0.28782, 0.36034, 0.4398, 0.5357, respectively.

Results
Correlation results

Number of genes and samples used for the calculation are shown in Table 1. Figure 1 shows the distribution of calculated correlation coefficients and quantile-quantile plot of the calculated correlation coefficients against a normal distribution. Table 2 shows the top 20 features ordered by the value of correlation coefficients.

Table 1. Counts of mRNA and number of samples in copy number and expression data sets and common to both

Category | Copy number | Expression | Common
--- | --- | --- | ---
Sample | 162 | 69 | 68
Genes | 29390 | 17815 | 15551

Figure 1. Summary figures. Left: histogram showing the distribution of the calculated correlations across samples for all Genes. Right: QQ plot of the calculated correlations across samples. The QQ plot is used to plot the quantiles of the calculated correlation coefficients against that derived from a normal distribution. Points deviating from the blue line indicate deviation from normality.

Table 2. Get Full Table Top 20 features (defined by the feature column) ranked by correlation coefficients

feature | r | p-value | q-value | chrom | start | end | geneid
--- | --- | --- | --- | --- | --- | --- | ---
CNOT7 | 0.8524 | 0 | 0 | 8 | 17131108 | 17148758 | 29883
APTX | 0.8465 | 0 | 0 | 9 | 32962608 | 32991626 | 54840
DSTN | 0.8338 | 0 | 0 | 20 | 17498599 | 17536652 | 11034
VPS37A | 0.8271 | 0 | 0 | 8 | 17148851 | 17197418 | 137492
PSMF1 | 0.8221 | 0 | 0 | 20 | 1041939 | 1095971 | 9491
TSPAN14 | 0.817 | 0 | 0 | 10 | 82204047 | 82269366 | 81619
PINX1 | 0.816 | 0 | 0 | 8 | 10659883 | 10734796 | 54984
DYNLRB1 | 0.8114 | 0 | 0 | 20 | 32567865 | 32592423 | 83658
CDC16 | 0.8089 | 0 | 0 | 13 | 114018476 | 114056252 | 8881
GTF2E2 | 0.8062 | 0 | 0 | 8 | 30555573 | 30635274 | 2961
TMEM11 | 0.8041 | 0 | 0 | 17 | 21041855 | 21058297 | 8834
DDX20 | 0.803 | 2.22044604925031e-16 | 1.09728331689964e-13 | 1 | 112099777 | 112111722 | 11218
TMEM93 | 0.7982 | 4.44089209850063e-16 | 1.75565330703942e-13 | 17 | 3518839 | 3519711 | 83460
CUL4A | 0.7961 | 4.44089209850063e-16 | 1.75565330703942e-13 | 13 | 112911087 | 112967393 | 8451
C20orf77 | 0.7949 | 4.44089209850063e-16 | 1.75565330703942e-13 | 20 | 36095467 | 36154632 | 58490
LOC400506 | 0.7926 | 8.88178419700125e-16 | 3.09821171830485e-13 | 16 | 19625733 | 19633856 | 400506
C20orf72 | 0.791 | 8.88178419700125e-16 | 3.09821171830485e-13 | 20 | 17897762 | 17919761 | 92667
CTNNBL1 | 0.7891 | 1.33226762955019e-15 | 4.15812625351441e-13 | 20 | 35755848 | 35933934 | 56259
ZNF133 | 0.7886 | 1.33226762955019e-15 | 4.15812625351441e-13 | 20 | 18217157 | 18245640 | 7692
MRPL51 | 0.7848 | 2.22044604925031e-15 | 6.58369990139781e-13 | 12 | 6471577 | 6472718 | 51258

Methods & Data
Input

Gene level (TCGA Level III) expression data and copy number data of the corresponding loci derived by using the CNTools package of Bioconductor were used for the calculations. Pearson correlation coefficients were calculated for each pair of genes shared by the two data sets across all the samples that were common.

Correlation across sample

Pairwise correlations between the log2 copy numbers and expressions of each gene across samples were calculated using Pearson correlation.

Download Results

This is an experimental feature. The full results of the analysis summarized in this report can be downloaded from the TCGA Data Coordination Center.

- Analysis Results (MD5 checksum)

- Auxiliary Data (MD5 checksum)

- MAGE-TAB File (MD5 checksum)

Copyright © 2013 Broad Institute TCGA GDAC as part of the TCGA Research Network. All rights reserved.
Made with Nozzle