The remodeling roles of lipid metabolism in colorectal cancer cells and immune microenvironment

Lipid is a key component of plasma membrane,which plays an important role in the regulation of various cell biological behaviors,including cell proliferation,growth,differentiation and intracellular signal transduction.Studies have shown that abnormal lipid metabolism is involved in many malignant processes,including colorectal cancer(CRC).Lipid metabolism in CRC cells can be regulated not only by intracellular signals,but also by various components in the tumor microenvironment,including various cells,cytokines,DNA,RNA,and nutrients including lipids.In contrast,abnormal lipid metabolism provides energy and nutrition support for abnormal malignant growth and distal metastasis of CRC cells.In this review,we highlight the remodeling roles of lipid metabolism crosstalk between the CRC cells and the components of tumor microenvironment.

Overexpression of catechol-O-methyltransferase occurs early in the progression of pancreatic cancer

Aims:Catechol-O-methyltransferase(COMT)plays a role in many kinds of cancer,and its high expression in pancreatic cancer has been found to be related to better prognosis.However,the expression and biological significance of COMT in multistep pancreatic cancerogenesis is not clear.Main methods:Six LSL-Kras^(G12D)-positive and Pdx1-Cre-positive mice(Kras^(G12D)mice),6 wild-type mice and 1 human tissue microarray were used in this study.COMT protein expression was measured by immunohistochemistry,and DNA chips were made for use in COMT mRNA assays.Keyfindings:The expression of COMT in pancreatic intraepithelial neoplasias(PanINs)from Kras^(G12D)mice was significantly higher than that in normal pancreatic tissue from wild-type mice,both in terms of protein level and mRNA expression.The median COMT immunohistochemistry expression scores in human PanIN-1 and PanIN-2 were 70 and 160,respectively,which were significantly lower than the score of 170 observed in pancreatic ductal adenocarcinoma(PDAC)(P=.024 and.037,respectively)and significantly higher than the score of 25 observed in pancreatitis(P=.01 and.008,respectively).Significance:In the development of pancreatic cancer from chronic pancreatitis and in the transition of PanIN to PDAC,we observed significantly increased expression of COMT.These data predict that the overexpression of COMT is an early event in the multistep process of pancreatic cancerogenesis.