Comparison of baseline characteristics for lung cancer (LC) case and control subjects
General characteristics of the case and control group are listed in the Table 1. In the study, the mean age of case group was 58.0±10.55 years and that of the control group was 57.27±10.85 years. There was no statistical difference between them (p=0.227). For the case group, 75.3% were males and 24.7% were females, and for the control group 75.6% were males and 24.4% were females. There was no statistical difference between the two groups (p=0.911). In the case group, pathologic types were mainly small cell lung cancer (SCLC), squamous cell carcinoma (SQC) and adenocarcinoma (ADC), accounting for 95.1% of the total cases. In addition, the number of patients with lymph node metastasis was 14.4% more than that no lymph node metastasis, and 48.6% of case group had advanced stage (stage III and stage IV).
List of research SNPs, positions, and genotyping data
Table 2 shows the research SNPs of CYP19A1 and their information. From the table, the research SNPs all fulfil HWE (p>0.05), in addition the table shows the genotype call rates that ranged from 99.4 to 99.9%.
Association of the minimum allele frequencies of CYP19A1 research SNPs with lung cancer (LC) risk
We analyzed five SNPs of CYP19A1 in the study. Table 3 illustrates the frequency distribution for the minimum alleles in the cases and controls. The minimum allele frequencies of rs4646, rs6493487 and rs17601876 in case group are lower than those in the control group. The allele A of rs4646 (OR=0.77, p=0.010), allele G of rs6493487 (OR=0.76, p=0.006) and allele A of rs17601876 (OR=0.69, p=1.15E-04) are associated with lower LC risk.
Association of CYP19A1 research SNPs Genotype with lung cancer (LC) risk
Table 4 displays the genotypes of rs4646 (p=0.035), rs6493487 (p=0.023), rs1062033 (p=0.009) and rs17601876 (p=0.001) are significantly different between the case and the control. In the table, the AA of rs4646 (OR=0.58, p=0.026), the rs6493487 (GG, OR=0.56, p=0.023; GA, OR=0.77, p=0.047) and the rs17601876(AA, OR=0.44, p=4.75E-04; AG, OR=0.71, p=0.009) of all have shown to link to decreasing the risk of LC, while the GG of rs1062033 (OR=1.49, p=0.029) shows to increase the LC risk, and the rs3751599 shows no association with the risk of LC. There are still same after adjusted for age and sex.
Association of CYP19A1 research SNPs with lung cancer (LC) risk in genetic model analysis
Table 5 summarizes the correlation between research SNPs and lung cancer in different genetic models including dominant, recessive, and additive genetic model. Same as genotype model, rs17601876 was associated with the reduction of LC risk in all three models. However, rs4646 and rs6493487 were only associated with lower LC risk in dominant and additive model, and rs1062033 was only related with higher LC risk in recessive model.
Association of CYP19A1 research SNPs with lung cancer (LC) risk in different gender
Table 6 demonstrates only rs17601876 is related to LC risk in male (AA, OR=0.52, p=0.012; AG, OR=0.74, p=0.047). Moreover, the GG of rs6493487 (OR=0.31, p= 0.037) and the AA of rs17601876 (OR=0.24, p=0.009) are associated with lowering the risk of LC in females.
Association of CYP19A1 research SNPs with lung cancer (LC) risk in different age
Table 7 shows all research SNPs have no significant association with LC in <58 years. But in ≥58, the AC of rs4646 (OR=0.66, p=0.021), the GA of rs6493487 (OR=0.65, p=0.021) and rs17601876 (AA, OR=0.39, p=0.001; AG, OR=0.57, p=0.002) are shown to decrease the risk of LC, while the GG of rs1062033 (OR=2.09, p= 0.003) increases the risk of LC.
Association of CYP19A1 research SNPs with lung cancer (LC) risk in different pathologic type
Table 8 indicates the AA of rs17601876 (OR=0.41, p=0.048) in SCLC, the rs4646 (AA, OR=0.41, p=0.027), rs6493487 (GA, OR=0.65, p=0.024), and rs17601876 (AA, OR=0.34, p=0.005) in SQC are shown to lower the risk of LC. Interestingly, research SNPs have no relationship with LC risk in ADC.