Correlation between mutation rate and clinical features
Glioma (Primary solid tumor)
02 April 2015  |  analyses__2015_04_02
Maintainer Information
Citation Information
Maintained by Juok Cho (Broad Institute)
Cite as Broad Institute TCGA Genome Data Analysis Center (2015): Correlation between mutation rate and clinical features. Broad Institute of MIT and Harvard. doi:10.7908/C1BG2N0M
Overview
Introduction

This pipeline uses various statistical tests to identify selected clinical features related to mutation rate.

Summary

Testing the association between 2 variables and 10 clinical features across 751 samples, statistically thresholded by P value < 0.05 and Q value < 0.3, 6 clinical features related to at least one variables.

  • 2 variables correlated to 'AGE'.

    • MUTATIONRATE_NONSYNONYMOUS ,  MUTATIONRATE_SILENT

  • 2 variables correlated to 'PRIMARY_SITE_OF_DISEASE'.

    • MUTATIONRATE_NONSYNONYMOUS ,  MUTATIONRATE_SILENT

  • 1 variable correlated to 'GENDER'.

    • MUTATIONRATE_SILENT

  • 2 variables correlated to 'KARNOFSKY_PERFORMANCE_SCORE'.

    • MUTATIONRATE_SILENT ,  MUTATIONRATE_NONSYNONYMOUS

  • 2 variables correlated to 'HISTOLOGICAL_TYPE'.

    • MUTATIONRATE_NONSYNONYMOUS ,  MUTATIONRATE_SILENT

  • 2 variables correlated to 'RADIATIONS_RADIATION_REGIMENINDICATION'.

    • MUTATIONRATE_NONSYNONYMOUS ,  MUTATIONRATE_SILENT

  • No variables correlated to 'DAYS_TO_DEATH_OR_LAST_FUP', 'AGE_mutation.rate', 'RACE', and 'ETHNICITY'.

Results
Overview of the results

Complete statistical result table is provided in Supplement Table 1

Table 1.  Get Full Table This table shows the clinical features, statistical methods used, and the number of variables that are significantly associated with each clinical feature at P value < 0.05 and Q value < 0.3.

Clinical feature Statistical test Significant variables Associated with                 Associated with
DAYS_TO_DEATH_OR_LAST_FUP Cox regression test   N=0        
AGE Spearman correlation test N=2 older N=2 younger N=0
AGE Linear Regression Analysis   N=0        
PRIMARY_SITE_OF_DISEASE Wilcoxon test N=2 central nervous system N=2 brain N=0
GENDER Wilcoxon test N=1 male N=1 female N=0
KARNOFSKY_PERFORMANCE_SCORE Spearman correlation test N=2 higher score N=0 lower score N=2
HISTOLOGICAL_TYPE Kruskal-Wallis test N=2        
RADIATIONS_RADIATION_REGIMENINDICATION Wilcoxon test N=2 yes N=2 no N=0
RACE Kruskal-Wallis test   N=0        
ETHNICITY Wilcoxon test   N=0        
Clinical variable #1: 'DAYS_TO_DEATH_OR_LAST_FUP'

No variable related to 'DAYS_TO_DEATH_OR_LAST_FUP'.

Table S1.  Basic characteristics of clinical feature: 'DAYS_TO_DEATH_OR_LAST_FUP'

DAYS_TO_DEATH_OR_LAST_FUP Duration (Months) 0-211.2 (median=15.2)
  censored N = 447
  death N = 303
     
  Significant variables N = 0
Clinical variable #2: 'AGE'

2 variables related to 'AGE'.

Table S2.  Basic characteristics of clinical feature: 'AGE'

AGE Mean (SD) 49.67 (16)
  Significant variables N = 2
  pos. correlated 2
  neg. correlated 0
List of 2 variables associated with 'AGE'

Table S3.  Get Full Table List of 2 variables significantly correlated to 'AGE' by Spearman correlation test

SpearmanCorr corrP Q
MUTATIONRATE_NONSYNONYMOUS 0.6248 1.985e-82 3.97e-82
MUTATIONRATE_SILENT 0.6192 1.392e-80 1.39e-80
Clinical variable #3: 'AGE'

No variable related to 'AGE'.

Table S4.  Basic characteristics of clinical feature: 'AGE'

AGE Mean (SD) 49.67 (16)
  Significant variables N = 0
Clinical variable #4: 'PRIMARY_SITE_OF_DISEASE'

2 variables related to 'PRIMARY_SITE_OF_DISEASE'.

Table S5.  Basic characteristics of clinical feature: 'PRIMARY_SITE_OF_DISEASE'

PRIMARY_SITE_OF_DISEASE Labels N
  BRAIN 278
  CENTRAL NERVOUS SYSTEM 473
     
  Significant variables N = 2
  Higher in CENTRAL NERVOUS SYSTEM 2
  Higher in BRAIN 0
List of 2 variables associated with 'PRIMARY_SITE_OF_DISEASE'

Table S6.  Get Full Table List of 2 variables differentially expressed by 'PRIMARY_SITE_OF_DISEASE'

W(pos if higher in 'CENTRAL NERVOUS SYSTEM') wilcoxontestP Q AUC
MUTATIONRATE_NONSYNONYMOUS 26606 2.48e-42 4.96e-42 0.7977
MUTATIONRATE_SILENT 27899 1.076e-39 1.08e-39 0.7878
Clinical variable #5: 'GENDER'

One variable related to 'GENDER'.

Table S7.  Basic characteristics of clinical feature: 'GENDER'

GENDER Labels N
  FEMALE 307
  MALE 444
     
  Significant variables N = 1
  Higher in MALE 1
  Higher in FEMALE 0
List of one variable associated with 'GENDER'

Table S8.  Get Full Table List of one variable differentially expressed by 'GENDER'. 0 significant gene(s) located in sex chromosomes is(are) filtered out.

W(pos if higher in 'MALE') wilcoxontestP Q AUC
MUTATIONRATE_SILENT 59415 0.002791 0.00558 0.5641
Clinical variable #6: 'KARNOFSKY_PERFORMANCE_SCORE'

2 variables related to 'KARNOFSKY_PERFORMANCE_SCORE'.

Table S9.  Basic characteristics of clinical feature: 'KARNOFSKY_PERFORMANCE_SCORE'

KARNOFSKY_PERFORMANCE_SCORE Mean (SD) 82.77 (15)
  Significant variables N = 2
  pos. correlated 0
  neg. correlated 2
List of 2 variables associated with 'KARNOFSKY_PERFORMANCE_SCORE'

Table S10.  Get Full Table List of 2 variables significantly correlated to 'KARNOFSKY_PERFORMANCE_SCORE' by Spearman correlation test

SpearmanCorr corrP Q
MUTATIONRATE_SILENT -0.2865 2.614e-10 5.23e-10
MUTATIONRATE_NONSYNONYMOUS -0.2643 6.186e-09 6.19e-09
Clinical variable #7: 'HISTOLOGICAL_TYPE'

2 variables related to 'HISTOLOGICAL_TYPE'.

Table S11.  Basic characteristics of clinical feature: 'HISTOLOGICAL_TYPE'

HISTOLOGICAL_TYPE Labels N
  ASTROCYTOMA 175
  GLIOBLASTOMA MULTIFORME (GBM) 9
  OLIGOASTROCYTOMA 119
  OLIGODENDROGLIOMA 179
  TREATED PRIMARY GBM 4
  UNTREATED PRIMARY (DE NOVO) GBM 265
     
  Significant variables N = 2
List of 2 variables associated with 'HISTOLOGICAL_TYPE'

Table S12.  Get Full Table List of 2 variables differentially expressed by 'HISTOLOGICAL_TYPE'

kruskal_wallis_P Q
MUTATIONRATE_NONSYNONYMOUS 5.856e-43 1.17e-42
MUTATIONRATE_SILENT 1.3e-40 1.3e-40
Clinical variable #8: 'RADIATIONS_RADIATION_REGIMENINDICATION'

2 variables related to 'RADIATIONS_RADIATION_REGIMENINDICATION'.

Table S13.  Basic characteristics of clinical feature: 'RADIATIONS_RADIATION_REGIMENINDICATION'

RADIATIONS_RADIATION_REGIMENINDICATION Labels N
  NO 278
  YES 473
     
  Significant variables N = 2
  Higher in YES 2
  Higher in NO 0
List of 2 variables associated with 'RADIATIONS_RADIATION_REGIMENINDICATION'

Table S14.  Get Full Table List of 2 variables differentially expressed by 'RADIATIONS_RADIATION_REGIMENINDICATION'

W(pos if higher in 'YES') wilcoxontestP Q AUC
MUTATIONRATE_NONSYNONYMOUS 42646 8.464e-16 1.69e-15 0.6757
MUTATIONRATE_SILENT 45525 1.863e-12 1.86e-12 0.6538
Clinical variable #9: 'RACE'

No variable related to 'RACE'.

Table S15.  Basic characteristics of clinical feature: 'RACE'

RACE Labels N
  AMERICAN INDIAN OR ALASKA NATIVE 1
  ASIAN 13
  BLACK OR AFRICAN AMERICAN 32
  WHITE 688
     
  Significant variables N = 0
Clinical variable #10: 'ETHNICITY'

No variable related to 'ETHNICITY'.

Table S16.  Basic characteristics of clinical feature: 'ETHNICITY'

ETHNICITY Labels N
  HISPANIC OR LATINO 21
  NOT HISPANIC OR LATINO 640
     
  Significant variables N = 0
Methods & Data
Input
  • Expresson data file = GBMLGG-TP.patients.counts_and_rates.txt

  • Clinical data file = GBMLGG-TP.merged_data.txt

  • Number of patients = 751

  • Number of variables = 2

  • Number of clinical features = 10

Selected clinical features
  • For clinical features selected for this analysis and their value conozzle.versions, please find a documentation on selected CDEs .

  • Survival time data

    • Survival time data is a combined value of days_to_death and days_to_last_followup. For each patient, it creates a combined value 'days_to_death_or_last_fup' using conversion process below.

      • if 'vital_status'==1(dead), 'days_to_last_followup' is always NA. Thus, uses 'days_to_death' value for 'days_to_death_or_fup'

      • if 'vital_status'==0(alive),

        • if 'days_to_death'==NA & 'days_to_last_followup'!=NA, uses 'days_to_last_followup' value for 'days_to_death_or_fup'

        • if 'days_to_death'!=NA, excludes this case in survival analysis and report the case.

      • if 'vital_status'==NA,excludes this case in survival analysis and report the case.

    • cf. In certain diesase types such as SKCM, days_to_death parameter is replaced with time_from_specimen_dx or time_from_specimen_procurement_to_death .

  • This analysis excluded clinical variables that has only NA values.

Survival analysis

For survival clinical features, Wald's test in univariate Cox regression analysis with proportional hazards model (Andersen and Gill 1982) was used to estimate the P values using the 'coxph' function in R. Kaplan-Meier survival curves were plot using the four quartile subgroups of patients based on expression levels

Correlation analysis

For continuous numerical clinical features, Spearman's rank correlation coefficients (Spearman 1904) and two-tailed P values were estimated using 'cor.test' function in R

Wilcoxon rank sum test (Mann-Whitney U test)

For two groups (mutant or wild-type) of continuous type of clinical data, wilcoxon rank sum test (Mann and Whitney, 1947) was applied to compare their mean difference using 'wilcox.test(continuous.clinical ~ as.factor(group), exact=FALSE)' function in R. This test is equivalent to the Mann-Whitney test.

Q value calculation

For multiple hypothesis correction, Q value is the False Discovery Rate (FDR) analogue of the P value (Benjamini and Hochberg 1995), defined as the minimum FDR at which the test may be called significant. We used the 'Benjamini and Hochberg' method of 'p.adjust' function in R to convert P values into Q values.

Download Results

In addition to the links below, the full results of the analysis summarized in this report can also be downloaded programmatically using firehose_get, or interactively from either the Broad GDAC website or TCGA Data Coordination Center Portal.

References
[1] Andersen and Gill, Cox's regression model for counting processes, a large sample study, Annals of Statistics 10(4):1100-1120 (1982)
[2] Spearman, C, The proof and measurement of association between two things, Amer. J. Psychol 15:72-101 (1904)
[3] Mann and Whitney, On a Test of Whether one of Two Random Variables is Stochastically Larger than the Other, Annals of Mathematical Statistics 18 (1), 50-60 (1947)
[4] Benjamini and Hochberg, Controlling the false discovery rate: a practical and powerful approach to multiple testing, Journal of the Royal Statistical Society Series B 59:289-300 (1995)