Correlation of TNF-α and TGF-β polymorphisms with protein levels in pancreatic ductal adenocarcinoma and colorectal cancer

Aim of the study
To determine the correlation of protein serum levels of two cytokines and their polymorphisms, which have an influence on their expression.

Material and methods
The study group consisted of 65 patients (33 men, 31 women) who met the criteria for inclusion and exclusion of pancreatic cancer, and 41 patients (25 men, 16 women) with colorectal cancer. The control group consisted of 100 healthy volunteers (63 men, 37 women). Detection of polymorphisms was performed using TaqMan probes, and concentration of proteins by ELISA method.

Results
The mean TNF-α concentration in patients with colorectal cancer was significantly higher compared to the control group, p < 0.0001. A statistically significant difference was noted when comparing both study groups, p = 0.0009. The analyses show that the occurrence of the polymorphic genotype -308AA of the TNF-α gene was not correlated with the increased concentration of the examined protein in patients with both pancreatic and colorectal cancer. It was also noted that the concentration of TGF-β protein was significantly higher in patients with colorectal cancer than in patients with pancreatic cancer. These results also proved to be statistically significant, p = 0.0353.

Conclusions
The only statistically significant effects were the correlations between patients belonging to a specific group (pancreatic cancer/colorectal cancer/control) and average protein levels. There was no effect of sex or genotype on the occurrence of elevated levels of TNF-α and TGF-β protein control, despite their variability in particular types of cancer.