Department of Biochemistry, Memorial University of Newfoundland, 232 Elizabeth Ave., St. John's, NL, A1B 3X9, Canada.
BMC Res Notes. 2021 Aug 17;14(1):315. doi: 10.1186/s13104-021-05728-z.
Breast cancer cell growth and proliferation requires lipids for energy production, cell membrane synthesis, or as signaling molecules. Lipids can be delivered to cells by lipoprotein lipase (LPL), an extracellular lipase that hydrolyzes triacylglycerols and phospholipids from lipoproteins, that is expressed by adipose tissue and some breast cancer cell lines. Studies have shown that lipoprotein hydrolysis products induce pro-inflammatory cytokine secretion by endothelial cells. Thus, our objective was to determine if hydrolysis products generated by LPL from total lipoproteins can also promote pro-inflammatory cytokine secretion from breast cancer cells.
Using cytokine arrays, we found that MDA-MB-231 cells increased secretion of seven cytokines in response to treatment with lipoprotein hydrolysis products. In contrast, MCF-7 cells showed decreased secretion of two cytokines. Expanding the analysis to additional cell lines by ELISA, we found increased secretion of TNF-α and IL-6 by MDA-MB-468 cells, and increased secretion of IL-4 by MDA-MB-468 and SKBR3 cells. The changes to cytokine secretion profiles of the breast cancer cell types examined, including the non-cancerous MCF-10a breast cells, were independent of increased cell metabolic activity. These results provide information on how lipoprotein hydrolysis products within the tumor microenvironment might affect breast cancer cell viability and progression.
乳腺癌细胞的生长和增殖需要脂质来提供能量、合成细胞膜或作为信号分子。脂蛋白脂肪酶（LPL）可以将脂质输送到细胞中，LPL 是一种细胞外脂肪酶，可从脂蛋白中水解三酰甘油和磷脂，在脂肪组织和一些乳腺癌细胞系中表达。研究表明，脂蛋白水解产物可诱导内皮细胞分泌促炎细胞因子。因此，我们的目的是确定来自总脂蛋白的 LPL 产生的水解产物是否也能促进乳腺癌细胞促炎细胞因子的分泌。
通过细胞因子阵列，我们发现 MDA-MB-231 细胞在接受脂蛋白水解产物处理后，七种细胞因子的分泌增加。相比之下，MCF-7 细胞的两种细胞因子分泌减少。通过 ELISA 对其他细胞系进行扩展分析，我们发现 MDA-MB-468 细胞中 TNF-α和 IL-6 的分泌增加，MDA-MB-468 和 SKBR3 细胞中 IL-4 的分泌增加。所研究的乳腺癌细胞类型的细胞因子分泌谱的变化，包括非癌性 MCF-10a 乳腺细胞，与细胞代谢活性的增加无关。这些结果提供了关于肿瘤微环境中的脂蛋白水解产物如何影响乳腺癌细胞活力和进展的信息。
