Summary:
A total of 58 CRC patients participated in the study and successfully genotyped
for rs3130 and rs2286455 polymorphisms of the CD133 gene. The allelic
frequencies observed for both polymorphisms were within the probability limits
of Hardy-Weinberg equilibrium (P > 0.05). Until December 31, 2014, 21 (36.21 %)
patients were characterized with SD disease, whereas 37 (63.79 %) with PD. Of
the 58 patients, 12 patients have died. Concerning KRAS mutation status, 33 of
all patients tested were carriers of codon 12 mutated allele and 5 were
carriers of the codon 13 mutated allele. There was not statistically
significant differences between carriers of KRAS mutated alleles between SD and
PD patients group (p = 0.76). Table 2 illustrates the distributions of
genotypes for the rs3130, and rs2286455 polymorphisms. As indicated in Table 3,
no significant difference was found between response rates and both rs3130 and
rs2286455 genotypes.
The most frequent major toxicities observed were nausea (22 patients) and
neutropenia (14 patients). As illustrated in Table 4, no statistically
significant difference was observed between toxicity and rs3130 and rs2286455
genotypes. However, the correlation between rs3130 CC genotype and reduced
toxicity to therapy almost reached statistical significance (p=0.05).
Table 5 shows the association of CD133 genotypes with overall survival. During
the study period, there were 12 deaths among subjects who were included in the
genotype study. The survival was calculated from the date of the first
treatment with bevacizumab combinations until death from any cause. The rs3130
CC genotype was found to be related with a significantly lower overall survival
in our study, whereas no significant association with survival was found for
the rs226455 polymorphism. The Kaplan–Meier survival curves by genotypes…… are
presented in Fig………….
Keywords:
Metastatic colon cancer, Irinotecan, Polymorphism, CD 133, DPD, UGT1A1
