Peer Review #2 of "An examination of clinical differences between carriers and non-carriers of chromosome 8q24 risk alleles in a New Zealand Caucasian population with prostate cancer (v0.1)"

Abstract

Background: Prostate cancer makes up approximately 15% of all cancers diagnosed in men in developed nations and approximately 4% of cases in developing nations. Although it is clear that prostate cancer has a genetic component and single nucleotide polymorphisms (SNPs) can contribute to prostate cancer risk, detecting associations is difficult in multi-factorial diseases, as environmental and lifestyle factors also play a role. In this study, specific clinical characteristics, environmental factors and genetic risk factors were assessed for interaction with prostate cancer. Methods: 489 prostate cancer cases and 427 healthy controls were genotyped for SNPs found on chromosome 8q24 and a genetic risk score was calculated. In addition the SNPs were tested for an association with a number of clinical and environmental factors. Results: Age and tobacco use were positively, whilst alcohol consumption was negatively associated with prostate cancer risk. The following SNPs found on chromosome 8q24 were statistically significantly associated with prostate cancer: rs10086908, rs16901979; rs1447295 and rs4242382. No association between Gleason score and smoking status, or between Gleason score and genotype were detected. Conclusion: A genetic risk score was calculated based on the 15 SNPs tested and found to be significantly associated with prostate cancer risk. Smoking significantly contributed to the risk of developing prostate cancer, and this risk was further increased by the presence of four SNPs in the 8q24 chromosomal region.