Abstract
The role of inflammation in colorectal carcinogenesis may differ according to individuals’ genetic variations. Therefore, we investigated whether genetic susceptibility alters the association between inflammatory potential of diet and the risk of colorectal cancer within the Korean population. We genotyped four polymorphisms in four genes (IL1B, TNF, PPARG, and PPARGC1A) and calculated the dietary inflammatory index (DII) in a case-control study with 701 colorectal cancer patients and 1,402 controls. Among the investigated polymorphisms, heterozygous carriers of rs3774921 in PPARGC1A showed a higher risk of colorectal cancer (OR [95% CI] = 1.26 [1.02–1.55] for TC vs. TT). When the data were stratified by rs3774921 genetic variant, the association of a pro-inflammatory diet with colorectal cancer risk was more prominent among homozygous variant allele carriers (OR [95% CI] = 5.15 [2.35–11.29] for high vs. low DII) (P for interaction = 0.009). When stratified by anatomic site, this association was much stronger for rectal cancer patients (OR [95% CI] = 8.06 [2.67–24.16] for high vs. low DII) (P for interaction = 0.006). Additionally, this interaction was stronger among those older than 50 years and not exercising regularly. Conversely, no association or interaction was found for the other investigated polymorphisms. In conclusion, the results of this study suggest that a pro-inflammatory diet may have a differential effect on colorectal cancer risk based on PPARGC1A genetic variation. This interaction may differ by anatomic location and other risk factors.
Highlights
Chronic inflammation is known to play an important role in colorectal cancer [1], and certain dietary components may modulate inflammation [2]
We examined whether the interaction between PPARGC1A genetic variation and diet-associated inflammation in relation to colorectal cancer risk could be modified by other risk factors such as age, body mass index (BMI), regular exercise, and smoking status
The present study suggests that in a Korean population, the association between the inflammatory potential of diet and colorectal cancer risk may differ according to genetic variations in PPARGC1A
Summary
Chronic inflammation is known to play an important role in colorectal cancer [1], and certain dietary components (e.g. fruit and vegetables, omega-3 polyunsaturated fatty acid, vitamin D) may modulate inflammation [2]. The dietary inflammatory index (DII) was developed to evaluate the inflammatory potential of diet [3]. This measure is reported to be associated with both the level of inflammatory cytokines [4] and the risk of colorectal cancer [5]. PPARγ coactivator 1-alpha (PGC-1α), which interact with PPARγ, is a transcriptional coactivator that has important functions in energy metabolism [13]. Both PPARγ and PGC-1α are reported to exert anti-inflammatory effects www.impactjournals.com/oncotarget
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call