Analyses on K-ras mutations and fascin expression in patients with cardia cancer.

Mutations of K-rat sarcoma (K-ras) in patients with cardia cancer and their effects on the expression of fascin were investigated. A total of 90 cardia cancer patients treated in Jining First People's Hospital from March 2014 to March 2017 were randomly selected. Genomic deoxyribonucleic acid (DNA) was extracted from paraffin-embedded cardia cancer specimens. Pyrosequencing was applied to detect sequences of K-ras gene in all patients and to analyze the mutations of K-ras gene. Then, genotyping of mutations at each mutation site was carried out using quantitative polymerase chain reaction (qPCR). The expression level of fascin in patients was measured via immunohistochemistry and qPCR. The results revealed that among 90 patients with cardia cancer, 21 patients had K-ras mutations (23.3%), including 20 cases of exon 12 mutation and 1 case of exon 13 mutation. Risk factor analyses revealed that alcohol abuse was a high risk factor for mutations (p<0.05). There was no significant difference in the mutation probability between heterozygotes and homozygotes for four mutations at codon 12 (p>0.05). The heterozygote at codon 13 had a higher mutation probability than homozygote (p<0.05). Immunohistochemistry suggested that the number of positive cells in the mutant group was larger than that in the non-mutant group (p<0.05). The results of qPCR showed that the expression level of fascin gene in the mutant group was 2.3 times higher than that in the non-mutant group (p<0.05). In conclusion, the probability of codon 12 mutation in K-ras gene is increased in patients with cardia cancer, and fascin is highly expressed in mutant patients, which is positively correlated with the mutations in K-ras gene.