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Zizogolu
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Doing kaplan meier plot with this data

I have normalized expression values of some genes in 76 patients and the how many days they have survived from their diagnosis with cancer like below

         Survival days  MTHFD1  SH3PXD2A    CAV1    ACTB    COL5A2  CDKN2C  BAG3    RALA    DST STEAP1  FZD1    IGFBP2  RBP1
GSM482796   1450    -0.538  0.261   0.368   0.671   0.194   -0.43   -0.179  0.551   -0.117  0.18    -0.527  -0.703  -0.0586
GSM482797   936 -0.209  0.097   -0.9    -0.307  0.0873  -0.516  -0.211  0.089   -0.0729 -0.0546 -0.132  -0.481  0.0215
GSM482798   936 -0.487  0.0853  -0.518  0.162   0.0326  -0.264  -0.0957 0.237   -0.0855 -0.243  -0.137  0.0581  0.11
GSM482799   2060    -0.355  0.0949  -0.198  0.232   0.0123  -0.506  0.0424  0.0626  0.128   0.0602  -0.538  -0.0969 0.277
GSM482800   2574    -0.547  0.0836  -0.81   -0.211  0.0928  -0.536  -0.301  0.126   -0.327  0.129   -0.251  0.536   0.02
GSM482801   2313    -0.484  -0.333  -1.13   0.312   -0.0508 -0.848  -0.0893 0.164   -0.15   -0.2    -0.85   0.0732  0.12
GSM482802   176 -0.343  0.194   1.29    0.436   0.221   -0.717  0.0727  0.65    1.29    0.857   0.00985 -0.384  0.289
GSM482803   NA  -0.623  0.176   -0.581  0.341   -0.0391 -0.446  -0.00736    -0.0541 -0.157  -0.197  -0.349  0.304   0.26
GSM482804   1327    -0.381  0.0195  -0.939  0.024   0.0151  -0.513  0.832   -0.055  0.0195  0.431   -0.673  -0.521  0.0575
GSM482805   1575    -0.167  0.0854  -0.411  0.0854  0.105   -0.296  0.101   0.31    0.798   -0.12   -0.152  0.119   0.142
GSM482806   687 -0.439  -0.0619 -1.06   0.0728  0.0771  -0.155  -0.232  0.164   -0.0181 0.196   0.449   0.748   -0.0259
GSM482807   736 -0.744  -0.191  -1.37   0.148   0.0684  -0.698  -0.292  0.187   -0.0628 -0.396  -0.598  -0.488  0.0977
GSM482808   816 -0.607  -0.194  -0.358  0.0134  0.159   -0.26   0.0238  -0.374  0.555   0.274   0.358   -0.0953 0.171
GSM482809   253 -0.354  0.121   -1.22   0.402   -0.0781 -0.699  -0.159  0.345   -0.0888 0.0523  -0.888  -0.759  0.0681
GSM482810   477 -0.607  -0.201  -1.05   0.551   -0.0554 -0.655  -0.148  -0.0741 -0.78   -0.31   -0.716  -0.154  0.0134
GSM482811   1035    -0.516  0.346   -0.62   0.0466  0.0884  -0.244  0.107   0.101   0.807   0.473   0.291   -0.417  0.0251
GSM482812   1984    -0.281  -0.0653 -0.917  0.255   -0.0167 -0.683  -0.0696 0.559   -0.175  -0.253  -0.458  -0.536  0.0461
GSM482813   2045    -0.42   0.0355  -0.792  0.513   0.158   -0.245  0.514   0.184   -0.211  -0.364  -0.573  0.183   0.049

EDITED

I have taken mean of the expression values for each patient and I have how many days each patient survived since diagnosis as below

> head(km)
    samples time        gene
1 GSM482796 1450 -0.11931980
2 GSM482797  936 -0.12209097
3 GSM482798  936 -0.10390257
4 GSM482799 2060 -0.07646939
5 GSM482800 2574 -0.16656837
6 GSM482801 2313 -0.12507939
>

I done so but nothing I got

> fit <- survfit(Surv(time) ~ gene, data = km)
> print(fit)
Call: survfit(formula = Surv(time) ~ gene, data = km)

                  n events median 0.95LCL 0.95UCL
gene=-0.333140816 1      1    859      NA      NA
gene=-0.307846735 1      1    347      NA      NA
gene=-0.303559694 1      1   1339      NA      NA
gene=-0.290518776 1      1     61      NA      NA

The question is if these genes increase survival time or not but likely I am doing wrong

By your help

> fit <- coxph(Surv(time) ~ gene, data = km)
> print(fit)
Call:
coxph(formula = Surv(time) ~ gene, data = km)

       coef exp(coef) se(coef)     z     p
gene 0.8664    2.3783   1.4520 0.597 0.551

Likelihood ratio test=0.35  on 1 df, p=0.5543
n= 69, number of events= 69 

For plotting I guess I do need another information because

 library("survminer")

> ggsurvplot(fit, data = km)
Error in ggsurvplot(fit, data = a) : object 'ggsurv' not found

Any help please?

Thanks

Zizogolu
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