So far, the etiology and pathogenesis of PCa is still elusive. Nevertheless, the continuous development of immunology and molecular biology methods provide the basis for the diagnosis and prognosis of prostate cancer [12, 13]. Lichtenstein et al  confirmed that 42% of the incidence of PCa can be attributed to genetic factors, and the rest is environment related. Studies on the relationship between the KLK3 and VDR polymorphisms as well as environmental factors and PCa occurance are very limited. Recent research on PCa whole-genome has revealed that several SNPs on chromosome 19q13.33 are related to the increased PCa risk . The most significantly associated SNP is rs2735839, located at the downstream 600 bp of the KLK3 gene and its encoding is KLK3, known as PSA. In an independent research on the group genome, including PCa, lung cancer, colon cancer, and ovarian cancer, Thomas et al.  found no PCa-susceptibility on chromosome 19. Our research has confirm that, patients with the SNP of the KLK3 gene, rs2735839, carrying the allele GG and AG, has a PCa risk 3.7 times higher than that carrying A homozygotes (OR = 3.78, 95% CI = 2.03 ~~ 7.07, P = 0.00). Xu et al.  reported that in terms of the chance of carrying dangerous allele G in rs2735839 SNPs, of localized PCa patients was significantly higher than of the advanced PCa patients (P = 0.03). Gleason score growth and the risk of gene frequencies confirmed no statistical significance, which is consistent with our finding. Zheng et al.  confirmed based on the research on the Chinese population, that the SNPs rs2723839 polymorphism of KLK3 related with the risk of PCa; Kader et al.  confirmed that the frequency of the rs2735839 gene and Gleason score are statistically significant. The difference in the conclusions may be due to genetic susceptibility and racial factors, as well as sufficiency of the sample size.
Lundin et al.  first reported that vitamin D (VD) may be associated with the causes of PCa. Cell culture experiments confirmed that VD inhibits PCa . Since VD produces physiological effects via its receptor (VDR), it is speculated that PCa susceptibility may depend on the polymorphism of the VDR genotype. The Taq I of several SNPs in VDR is located outside the 9th significant promoter region, which is SNPs rs731236. SNPs rs731236 and other flag material in this chromosomal region are stronly unbalanced; thus it is considered that this SNPs is strongly related to PCa occurance . Medeiros  confirmed that in the VDR Taq I genes, rs731236 polymorphism, people who carry allele C homozygotes only have 1/3 (OR = 0.34, 95% CI, 0.16 ~ 0.76, P <0.01) of the risk to have PCa compared with those who carry miscellaneous zygote or T homozygous, therefore CC homozygotes gene is thought to prevent individual from suffering from PCa. However Gsur et al.  confirmed that within the Caucasian population in Austria, the VDR Taq I gene polymorphism is not related to the risk of suffering from PCa; the frequencies of the CC genotype in PCa patients and the corresponding controls, are 18% and 12%, respectively, and difference is not statistically significant (OR = 1.76, 95% CI, 0.90 to 3.45, P = 0 07). Our study confirms that within the Chinese Han population, the appearing frequencies of the genotype TT, TC, and CC in the SNPs, rs731236 (T/C) VDR of PCa patients and the control group are 88.89%, 9.26%, 1.85% and 90.50%, 9.10%, 0.40%, (P = 0.643), and correlation is found between rs731236 and the occurrence PCa. Our research indicates that The rs731236 polymorphism may not be associated with PCa occurrence among the Chinese Han population, combined with the previous research, it suggest that gene polymorphism is different between different races.
Tumorigenesis is affected by both environmental and genetic factors. Univariate analysis of the environmental factors confirmed that alcohol consumption and tea consumpiton are related to prostate illness, where alcohol consumption increases the risk of suffering from PCa while tea drinking is a protective factor. Multivariate Logistic regression analysis confirmed that tea drinking reduces the PCa occurance. Epidemiological studies have pointed out that the lower occruance rate of PCa among Asian population compared with the Westerners may be realted to the larger conumption of tea by the former [25, 26]. The study has also found the correlation between the occurance of PCa and tea consumtion, which may be related to flavonols (protocatechuic) in green tea. Park  confirmed that protocatechuic can reduce PCa inplanted on mice. The analysis of environmental risk factors and genetic factors KLK3 gene polymorphisms (SNPs) rs2735839 revealed that multiplied interaction exists between tea consumption and rs2735839; Tea consumption may be against the dangerous gene GG + GA and protect people from PCa. Further in-depth research needs to be carry out in this aspect.
In summary, the results of this study suggest that the occurrence of PCa is related to the genotype of KLK3 SNPs rs2735839. The SNPs rs731236 genotype of VDR is not associated with PCa incidence. Environmental risk factors have impact on PCa occurance. Studies show that he expression of GOLPH3 and miR - 126 play a positive role in the malignant progression of PCa [28, 29]. The relationship between the genetic, environmental factors and PCa incidence still need further in-depth investigation with a largeer sample size in order to provide a scientific basis for PCa prevention and control.