Investigations were conducted in 81 primary
colorectal cancers. As a control, the same amount of sample was collected from macroscopically unchanged colon regions of the most distant location to the
cancer. Homogenisation of specimens provided 10% homogenates for our evaluations. Activity of
antioxidant enzymes and level of
glutathione were determined by spectrophotometry. HPLC revealed levels of
vitamins C and E and served as a method to detect terminal products of lipid peroxidation in
colorectal cancer.
RESULTS: Our studies demonstrated a statistically significant increase in the level of lipid peroxidation products (MDA-Adc.muc.-2.65+/-0.48 nmol/g, Adc.G3-2.15+/-0.44 nmol/g, clinical IV stage 4.04+/-0.47 nmol/g, P<0.001 and 4-HNE-Adc.muc. -0.44+/-0.07 nmol/g, Adc.G3-0.44+/-0.10 nmol/g, clinical IV stage 0.52+/-0.11 nmol/g, P<0.001) as well as increase of Cu,Zn-SOD (Adc.muc.-363+/-72 U/g, Adc.G3-318+/-48 U/g, clinical IV stage 421+/-58 U/g, P<0.001), GSH-Px (Adc.muc. -2143+/-623 U/g, Adc.G3-2005+/-591 U/g, clinical IV stage 2467+/-368 U/g, P<0.001) and
GSSG-R (Adc.muc.-880+/-194 U/g, Adc.G3-795+/-228 U/g, clinical IV stage 951+/-243 U/g, P<0.001) in primary tumour comparison with normal colon (MDA-1.39+/-0.15 nmol/g, HNE-0.29+/-0.03 nmol/g, Cu, Zn-SOD-117+/-25 U/g, GSH-Px-1723+/-189 U/g,
GSSG-R-625+/-112 U/g) especially in mucinous and G3-grade
adenocarcinomas as well as clinical IV stage of
colorectal cancer. We also observed a decrease of CAT activity (Adc.muc. -40+/-14 U/g, clinical IV stage 33+/-18 U/g vs 84+/-17 U/g, P<0.001) as well as a decreased level of
reduced glutathione (clinical IV stage 150+/-48 nmol/g vs 167+/-15 nmol/g, P<0.05) and
vitamins C and E (vit. C-clinical IV stage 325+/-92 nmol/g vs 513+/-64 nmol/g, P<0.001; vit. E-clinical IV stage 13.3+/-10.3 nmol/g vs 37.5+/-5.2 nmol/g).
CONCLUSION: