Neurokinin-2 receptor polymorphism predicts lymph node metastasis in colorectal cancer patients.

To analyze the single nucleotide polymorphisms (SNPs) of two subtypes of neurokinin (NK) receptors, and (also known as and ), in colorectal cancer (CRC), peripheral blood samples were collected from 199 CRC patients. Direct-sequencing was performed to identify the rs10198644 and rs4644560 SNPs. Genotype results were correlated with clinical factors. The allele frequencies of rs10198644 GC, CC and GG were 52, 17 and 31%, respectively, while that of rs4644560 GC, CC, and GG were 36, 50 and 14%, respectively. Patients with rs4644560 GC exhibited more positive lymph nodes than those with CC (mean, 2.2 vs. 1.3; P=0.016). Further analysis highlighted that the number of positive lymph nodes was also increased in the rs4644560 GC/ rs10198644 GG group compared with the rs4644560 GG/ rs10198644 GG group (mean, 2.2 vs. 0.9; P=0.04). These data suggested that the rs4644560 GC polymorphism alone or combination with rs10198644 GG may be a promising prognostic marker of lymph node metastasis in CRC patients.