Effect of SLC6A4 gene polymorphism on pain sensitivity in patients with lung cancer

Abstract

Objective To evaluate the effect of SLC6A4 gene polymorphism on pain sensitivity in the patients with lung cancer. Methods A total of 248 patients with pulmonary malignant tumor served as lung cancer group and 104 healthy subjects in the Physical Examination Center of our hospital served as control group.Patients with malignant pulmonary tumor in lung cancer group were further divided into 3 subgroups according to pain score and the three step analgesic ladder recommended by WHO(opioids was used when visual analogue scale [VAS] score≥4 points): painless subgroup, mild pain subgroup and moderate-severe pain subgroup.The consumption of opioids(based on requirement for morphine)within 24 h after pain relief(VAS score≤3 points)after treatment and VAS score before treatment were recorded.Venous blood samples were collected, and the genotypes were analyzed by polymerase chain reaction-restriction fragment length polymorphism. Results There was no significant difference in genotype frequency or allele frequency at rs4795541 and rs3813034 sites between lung cancer group and control group and among the three subgroups(P>0.05). There was no significant difference in VAS score before treatment or requirement for morphine between patients of different genotypes and alleles(P>0.05). There was no significant difference in VAS score before treatment or requirement for morphine between lung cancer patients with medium and low expression of serotonin transporter in 5-HTT-linked polymorphic region. Conclusion SLC6A4 gene polymorphism exerts no effect on pain sensitivity in the patients with lung cancer. Key words: Serotonin plasma membrane transport proteins; Polymorphism, single nucleotide; Neoplasms; Pain threshold