Laboratoire de Biochimie Médicale et de Biologie Moléculaire, CNRS FRE 3481, Université de Reims-Champagne-Ardenne, Reims, France.
PLoS One. 2013 Oct 2;8(10):e76232. doi: 10.1371/journal.pone.0076232. eCollection 2013.
Lumican, a small leucine-rich proteoglycan of the extracellular matrix, presents potent anti-tumor properties. Previous works from our group showed that lumican inhibited melanoma cell migration and tumor growth in vitro and in vivo. Melanoma cells adhered to lumican, resulting in a remodeling of their actin cytoskeleton and preventing their migration. In addition, we identified a sequence of 17 amino acids within the lumican core protein, named lumcorin, which was able to inhibit cell chemotaxis and reproduce anti-migratory effect of lumican in vitro. The aim of the present study was to characterize the anti-tumor mechanism of action of lumcorin. Lumcorin significantly decreased the growth in monolayer and in soft agar of two melanoma cell lines - mice B16F1 and human SK-MEL-28 cells - in comparison to controls. Addition of lumcorin to serum free medium significantly inhibited spontaneous motility of these two melanoma cell lines. To characterize the mechanisms involved in the inhibition of cell migration by lumcorin, the status of the phosphorylation/dephosphorylation of proteins was examined. Inhibition of focal adhesion kinase phosphorylation was observed in presence of lumcorin. Since cancer cells have been shown to migrate and to invade by mechanisms that involve matrix metalloproteinases (MMPs), the expression and activity of MMPs were analyzed. Lumcorin induced an accumulation of an intermediate form of MMP-14 (~59kDa), and inhibited MMP-14 activity. Additionally, we identified a short, 10 amino acids peptide within lumcorin sequence, which was able to reproduce its anti-tumor effect on melanoma cells. This peptide may have potential pharmacological applications.
赖氨酰聚糖，细胞外基质中的一种小型富含亮氨酸的蛋白聚糖，具有强大的抗肿瘤特性。我们小组的先前工作表明，赖氨酰聚糖可抑制黑色素瘤细胞在体外和体内的迁移和肿瘤生长。黑色素瘤细胞黏附于赖氨酰聚糖，导致其肌动蛋白细胞骨架重塑，从而阻止其迁移。此外，我们在赖氨酰聚糖核心蛋白中鉴定出一个由 17 个氨基酸组成的序列，命名为 lumcorin，它能够抑制细胞趋化性并在体外重现赖氨酰聚糖的抗迁移作用。本研究的目的是表征 lumcorin 的抗肿瘤作用机制。与对照组相比，lumcorin 显著降低了两种黑色素瘤细胞系（小鼠 B16F1 和人 SK-MEL-28 细胞）在单层和软琼脂中的生长。在无血清培养基中添加 lumcorin 可显著抑制这两种黑色素瘤细胞系的自发运动。为了表征 lumcorin 抑制细胞迁移的机制，检查了蛋白质磷酸化/去磷酸化的状态。在存在 lumcorin 的情况下，观察到焦点黏附激酶磷酸化的抑制。由于已经表明癌细胞通过涉及基质金属蛋白酶 (MMPs) 的机制迁移和侵袭，因此分析了 MMPs 的表达和活性。lumcorin 诱导 MMP-14 的中间形式（~59kDa）积累，并抑制 MMP-14 活性。此外，我们在 lumcorin 序列中鉴定出一个短的 10 个氨基酸肽，它能够重现其对黑色素瘤细胞的抗肿瘤作用。该肽可能具有潜在的药理学应用。
