Lipoprotein Lipase Activity and Gene Expression in Lung Cancer and in Adjacent Noncancer Lung Tissue

Abstract

The authors tested the hypothesis that lipoprotein lipase (LPL) gene expression and enzyme activity are increased in lung cancer tissue, as compared to adjacent, apparently healthy, lung tissue. Paired samples of lung cancer tissue and adjacent noncancer lung tissue were collected from 42 patients with resectable non-small cell lung cancer. LPL activity was higher in cancer tissue (1.9-fold median difference, P < .0001); however, LPL gene expression was higher in noncancer tissue (3.8-fold median difference, P < .0001). The higher LPL activity in lung cancer tissue provides a possible mechanism for increasing the supply of lipid nutrients to the tumor, necessary for tumor growth.

Lipoprotein lipase in non-small cell lung cancer tissue is highly expressed in a subpopulation of tumor-associated macrophages

“…Their strong LPL mRNA synthesis and exclusive localization in NSCLC tissue clarify our previous finding that in NSCLC tissue (but not in adjacent non-cancer lung tissue), gene expression is the principal regulator of LPL activity [3]. The whole tissue gene expression analysis, co-localization of LPL-overexpressing cells with CD14 antigens on the same tissue section and comparative distribution of LPL-overexpressing cells and anti-CD163-stained macrophages in consecutive tissue sections, demonstrate that these highly LPL-expressing cells are macrophages.…”

“…Forty-two patients undergoing surgical removal of resectable NSCLC were enrolled consecutively in the study, as described previously [3]. Samples of lung cancer tissue and of adjacent, visually unaffected tissue were cut from the resected lung within 15 min after the operation.…”

“…Presumed normal tissue, a According to the TNM classification [21]. b Previously estimated in the same tissues [3].…”

“…Further, LPL activity is highest in areas containing actively proliferating cells in a variety of human sarcomas and carcinomas [19]. Finally, LPL activity in NSCLC tissue is regulated primarily by LPL expression [3].…”

The Novel Anticancer Drug Hydroxytriolein Inhibits Lung Cancer Cell Proliferation via a Protein Kinase Cα– and Extracellular Signal-Regulated Kinase 1/2–Dependent Mechanism

“…We measured HTO and triolein metabolization by LPL, and we found that the latter was degraded approximately 4-fold faster than HTO in vitro. In addition, increased LPL activity has been reported in cancer tumors compared with normal lung tissue, most likely due to the energy requirements of tumor cells (Cerne et al, 2007), which potentially explains the lack of efficacy of olive oil despite its protective anticancer effects. LPL would hydrolyze triglycerides to fatty acids that the tumor could use as energy source.…”