Effects of cell membrane phospholipid level and protein kinase C isoenzyme expression on hepatic metastasis of colorectal carcinoma.
BACKGROUND
The molecular mechanism of hepatic metastasis of colorectal cancer is not well understood. The aim of this study was to assess the relations between phospholipid contents of cellular membrane and isoenzyme expression of protein kinase C (PKC) and their effects on hepatic metastasis of colorectal cancer.


METHODS
High performance liquid chromatography was used to detect contents of cell membrane phospholipids: phosphatidylinosital (PI), phosphatidylserine (PS), phosphatidylethanolamine (PE) and phosphatidylcholine (PC) in primary foci, paratumor mucosa and hepatic metastatic foci in patients with colorectal carcinoma. The mRNA expression levels of PKC-alpha, -betaII, -delta, -epsilon, -lambda, -zeta isoenzymes were detected with the QRT-PCR technique.


RESULTS
The levels of PI, PC and PE in primary foci and hepatic metastatic foci were higher than those in paratumor mucosa. The level of PE in hepatic metastatic foci was much higher than that in primary foci (t=98.88, P<0.01); but the levels of PI and PC were not significantly different between primary foci and hepatic metastatic foci (t=1.73, 1.36, P>0.05). The expression levels of PKC-betaII, -delta, -epsilon, -lambda, -zeta were enhanced in primary foci and hepatic metastatic foci, but the level of PKC-alpha in primary foci was decreased as compared with that in paratumor mucosa. The levels of PKC-delta, -epsilon, -lambda, -zeta in hepatic metastatic foci were higher than those in primary foci. A positive correlation was observed between the expression levels of PI, PC and PKC-betaII and also between those of PE and PKC-delta, -epsilon, -lambda, -zeta. However, there was a close negative correlation between PE and PKC-alpha.


CONCLUSIONS
Increased levels of PI and PC and decreased ratio of PKC-alpha to PKC-betaII are related to colorectal cancer genesis. Increased levels of PE, increased expression of PKC-delta, -epsilon, -lambda, -zeta isoenzymes and decreased level of PKC-alpha are related to hepatic metastasis in colorectal carcinoma.
Department of General Surgery, Beijing Military General Hospital, Beijing 100700, China. shiyongli@cnoperation.com
Shi-Yong
SY
Li
Bo
B
Yu
Ping
P
An
Zhen-Jia
ZJ
Liang
Shu-Jun
SJ
Yuan
Hui-Yun
HY
Cai
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002462:Cell Membrane / Q000201:enzymology; D015179:Colorectal Neoplasms / Q000473:pathology*; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007527:Isoenzymes / Q000235:genetics*; D008113:Liver Neoplasms / Q000503:physiopathology / Q000556:secondary*; D008297:Male; D008875:Middle Aged; D009092:Mucous Membrane / Q000201:enzymology; D010743:Phospholipids / Q000378:metabolism*; D011493:Protein Kinase C / Q000235:genetics*; D064546:Protein Kinase C beta; D051571:Protein Kinase C-alpha; D051745:Protein Kinase C-delta; D051744:Protein Kinase C-epsilon; D012333:RNA, Messenger / Q000032:analysis; D000099293:Protein Kinase C-lambda; D000099221:Protein Kinase C zeta
D007527:Isoenzymes; D010743:Phospholipids; D011493:Protein Kinase C; D064546:Protein Kinase C beta; D051571:Protein Kinase C-alpha; D051745:Protein Kinase C-delta; D051744:Protein Kinase C-epsilon; D012333:RNA, Messenger; D000099293:Protein Kinase C-lambda; D000099221:Protein Kinase C zeta; C496628:PRKCA protein, human; C497258:PRKCD protein, human; C497255:PRKCE protein, human