Correlation between APOBEC groups and selected clinical features
Overview
Introduction

This pipeline computes the correlation between APOBRC groups and selected clinical features.

Summary

Testing the association between APOBEC groups identified by 2 different apobec score and 12 clinical features across 376 patients, 5 significant findings detected with Q value < 0.25.

  • 3 subtypes identified in current cancer cohort by 'APOBEC MUTLOAD MINESTIMATE'. These subtypes correlate to 'Time to Death' and 'RACE'.

  • 3 subtypes identified in current cancer cohort by 'APOBEC ENRICH'. These subtypes correlate to 'Time to Death',  'PATHOLOGY_T_STAGE', and 'RACE'.

Results
Overview of the results

Table 1.  Get Full Table Overview of the association between APOBEC groups by 2 different APOBEC scores and 12 clinical features. Shown in the table are P values (Q values). Thresholded by Q value < 0.25, 5 significant findings detected.

Clinical
Features
Statistical
Tests
APOBEC
MUTLOAD
MINESTIMATE
APOBEC
ENRICH
Time to Death logrank test 0.0119
(0.0714)
0.00505
(0.0404)
YEARS TO BIRTH Kruskal-Wallis (anova) 0.764
(0.873)
0.639
(0.767)
NEOPLASM DISEASESTAGE Fisher's exact test 0.214
(0.348)
0.243
(0.364)
PATHOLOGY T STAGE Fisher's exact test 0.106
(0.289)
0.0342
(0.164)
PATHOLOGY N STAGE Fisher's exact test 0.17
(0.335)
0.168
(0.335)
PATHOLOGY M STAGE Fisher's exact test 0.547
(0.692)
0.0995
(0.289)
GENDER Fisher's exact test 0.122
(0.293)
0.845
(0.921)
KARNOFSKY PERFORMANCE SCORE Kruskal-Wallis (anova) 0.182
(0.335)
0.444
(0.606)
NUMBER PACK YEARS SMOKED Kruskal-Wallis (anova) 0.217
(0.348)
0.455
(0.606)
NUMBER OF LYMPH NODES Kruskal-Wallis (anova) 0.064
(0.256)
0.108
(0.289)
RACE Fisher's exact test 0.00034
(0.00408)
0.00016
(0.00384)
ETHNICITY Fisher's exact test 1
(1.00)
1
(1.00)
APOBEC group #1: 'APOBEC MUTLOAD MINESTIMATE'

Table S1.  Description of APOBEC group #1: 'APOBEC MUTLOAD MINESTIMATE'

Cluster Labels 0 HIGH LOW
Number of samples 46 126 204
'APOBEC MUTLOAD MINESTIMATE' versus 'Time to Death'

P value = 0.0119 (logrank test), Q value = 0.071

Table S2.  Clustering Approach #1: 'APOBEC MUTLOAD MINESTIMATE' versus Clinical Feature #1: 'Time to Death'

nPatients nDeath Duration Range (Median), Month
ALL 370 151 0.1 - 166.0 (15.6)
0 43 22 2.0 - 93.0 (13.0)
HIGH 126 41 0.4 - 166.0 (17.6)
LOW 201 88 0.1 - 140.8 (15.3)

Figure S1.  Get High-res Image Clustering Approach #1: 'APOBEC MUTLOAD MINESTIMATE' versus Clinical Feature #1: 'Time to Death'

'APOBEC MUTLOAD MINESTIMATE' versus 'RACE'

P value = 0.00034 (Fisher's exact test), Q value = 0.0041

Table S3.  Clustering Approach #1: 'APOBEC MUTLOAD MINESTIMATE' versus Clinical Feature #11: 'RACE'

nPatients ASIAN BLACK OR AFRICAN AMERICAN WHITE
ALL 38 21 301
0 13 5 26
HIGH 8 5 110
LOW 17 11 165

Figure S2.  Get High-res Image Clustering Approach #1: 'APOBEC MUTLOAD MINESTIMATE' versus Clinical Feature #11: 'RACE'

APOBEC group #2: 'APOBEC ENRICH'

Table S4.  Description of APOBEC group #2: 'APOBEC ENRICH'

Cluster Labels FC.HIGH.SIG FC.LOW.NONSIG FC.NEUTRAL
Number of samples 315 46 15
'APOBEC ENRICH' versus 'Time to Death'

P value = 0.00505 (logrank test), Q value = 0.04

Table S5.  Clustering Approach #2: 'APOBEC ENRICH' versus Clinical Feature #1: 'Time to Death'

nPatients nDeath Duration Range (Median), Month
ALL 370 151 0.1 - 166.0 (15.6)
FC.HIGH.SIG 312 120 0.4 - 166.0 (16.5)
FC.LOW.NONSIG 43 22 2.0 - 93.0 (13.0)
FC.NEUTRAL 15 9 0.1 - 30.9 (12.9)

Figure S3.  Get High-res Image Clustering Approach #2: 'APOBEC ENRICH' versus Clinical Feature #1: 'Time to Death'

'APOBEC ENRICH' versus 'PATHOLOGY_T_STAGE'

P value = 0.0342 (Fisher's exact test), Q value = 0.16

Table S6.  Clustering Approach #2: 'APOBEC ENRICH' versus Clinical Feature #4: 'PATHOLOGY_T_STAGE'

nPatients T0+T1+T2 T3 T4
ALL 114 179 52
FC.HIGH.SIG 89 158 41
FC.LOW.NONSIG 22 15 7
FC.NEUTRAL 3 6 4

Figure S4.  Get High-res Image Clustering Approach #2: 'APOBEC ENRICH' versus Clinical Feature #4: 'PATHOLOGY_T_STAGE'

'APOBEC ENRICH' versus 'RACE'

P value = 0.00016 (Fisher's exact test), Q value = 0.0038

Table S7.  Clustering Approach #2: 'APOBEC ENRICH' versus Clinical Feature #11: 'RACE'

nPatients ASIAN BLACK OR AFRICAN AMERICAN WHITE
ALL 38 21 301
FC.HIGH.SIG 23 16 264
FC.LOW.NONSIG 13 5 26
FC.NEUTRAL 2 0 11

Figure S5.  Get High-res Image Clustering Approach #2: 'APOBEC ENRICH' versus Clinical Feature #11: 'RACE'

Methods & Data
Input
  • APOBEC groups file = /xchip/cga/gdac-prod/tcga-gdac/jobResults/APOBEC_Pipelines/BLCA-TP/15185889/APOBEC_clinical_corr_input_15190444/APOBEC_for_clinical.correlaion.input.categorical.txt

  • Clinical data file = /xchip/cga/gdac-prod/tcga-gdac/jobResults/Append_Data/BLCA-TP/15076720/BLCA-TP.merged_data.txt

  • Number of patients = 376

  • Number of selected clinical features = 12

APOBEC classification

APOBEC classification based on APOBEC_MutLoad_MinEstimate : a. APOBEC non group -- samples with zero value, b. APOBEC hig group -- samples above median value in non zero samples, c. APOBEC hig group -- samples below median value in non zero samples.

APOBEC classification based on APOBEC_enrich : a. No Enrichmment group -- all samples with BH_Fisher_p-value_tCw >=0.05, b. Small enrichment group -- samples with BH_Fisher_p-value_tCw = < 0.05 and APOBEC_enrich=<2, c. High enrichment gruop -- samples with BH_Fisher_p-value_tCw =< 0.05 and APOBEC_enrich>2.

Survival analysis

For survival clinical features, the Kaplan-Meier survival curves of tumors with and without gene mutations were plotted and the statistical significance P values were estimated by logrank test (Bland and Altman 2004) using the 'survdiff' function in R

Fisher's exact test

For binary clinical features, two-tailed Fisher's exact tests (Fisher 1922) were used to estimate the P values using the 'fisher.test' function in R

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.

References
[1] Bland and Altman, Statistics notes: The logrank test, BMJ 328(7447):1073 (2004)
[2] Fisher, R.A., On the interpretation of chi-square from contingency tables, and the calculation of P, Journal of the Royal Statistical Society 85(1):87-94 (1922)
[3] 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)