Angiotensin-Converting Enzyme Gene Deletion Polymorphism is Associated with Lymph Node Metastasis in Colorectal Cancer Patients in a Chinese Population

BACKGROUND The purpose of this study was to assess the effect of angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism on the risk of lymph node metastasis (LNM) in colorectal cancer (CRC) patients. MATERIAL AND METHODS We enrolled 146 CRC patients and 106 healthy controls in this study. ACE gene I/D polymorphism was genotyped by polymerase chain reaction (PCR). Hardy-Weinberg equilibrium (HWE) was used to assess the goodness of fit of the genotypes. χ² test was used to calculate the differences of genotype and allele distributions. Odds ratios (ORs) with corresponding 95% confidence intervals (95% CIs) were used to analyze the association between ACE I/D polymorphism and LNM in CRC patients. RESULTS Insertion/deletion (ID) and deletion/deletion (DD) genotypes were frequently observed in CRC patients, but only DD genotype and D allele were related to the susceptibility of CRC (P=0.038, OR=2.158, 95%CI=1.039-4.480; P=0.026, OR=1.501, 95%CI=1.048-2.150). DD genotype and D allele also increased the risk of LNM in CRC patients (P=0.028, OR=2.844, 95%CI=1.107-7.038; P=0.026, OR=1.692, 95%CI=1.063-2.693). CONCLUSIONS DD genotype and D allele of ACE gene I/D polymorphism might increase the risk of LNM in CRC patients.