Millimaggi Danilo, Festuccia Claudio, Angelucci Adriano, D'Ascenzo Sandra, Rucci Nadia, Flati Silvio, Bologna Mauro, Teti Anna, Pavan Antonio, Dolo Vincenza
Department of Experimental Medicine, University of L'Aquila, 67100 L'Aquila, Italy.
Int J Oncol. 2006 Apr;28(4):909-14.
Although it has been shown that the cross-talk between osteoblasts and tumor cells stimulates proliferation and invasion of prostate carcinoma (PCa) cells, the molecular mechanisms underlying this event are largely unknown. In this study, we demonstrated that the PCa cells, PC3, derived from bone metastasis, undergo changes of their invasive capability if grown in the presence of osteoblast-derived conditioned media (OBCM). Specifically, they were able to organize tridimensional structures in Matrigel, such as large branching colonies, tube-like structures and clusters of proliferating cells, after treatment. At the ultrastructural level, we observed that PC3 cells grown in the presence of OBCM presented an increment of membrane activity with a blast of shed membrane vesicles from the cell surface. After 6 h of incubation, protein content was approximately 5-fold more elevated in vesicles isolated from PC3 cells cultured in OBCM than in unstimulated cultures. Gelatin zymography of vesicles collected from OBCM-treated PC3 cells showed an increment of lytic bands of MMP family members identified as pro-enzymatic and active forms of gelatinase A (MMP-2) and gelatinase B (MMP-9). By casein-plasminogen zymography, this latter culture also presented an elevated level of high-molecular weight urokinase plasminogen activator (HMW-uPA). Purified vesicles from OBCM-treated PC3 cells incubated with Matrigel cleaved its components more efficiently than vesicles from untreated PC3 cells. Collectively, these findings indicate that osteoblasts produce factor/s able to modify the invasive capability of prostate cancer cells, increasing the amount of shed vesicles and of their associated lytic enzymes.
尽管已有研究表明成骨细胞与肿瘤细胞之间的相互作用会刺激前列腺癌细胞（PCa）的增殖和侵袭，但其背后的分子机制仍 largely 未知。在本研究中，我们证明了源自骨转移的 PCa 细胞 PC3 在成骨细胞衍生的条件培养基（OBCM）存在下生长时，其侵袭能力会发生变化。具体而言，处理后它们能够在基质胶中形成三维结构，如大型分支菌落、管状结构和增殖细胞簇。在超微结构水平上，我们观察到在 OBCM 存在下生长的 PC3 细胞呈现出膜活性增加，细胞表面有大量脱落的膜泡。孵育 6 小时后，从在 OBCM 中培养的 PC3 细胞分离的囊泡中的蛋白质含量比未刺激的培养物中高出约 5 倍。对从 OBCM 处理的 PC3 细胞收集的囊泡进行明胶酶谱分析，结果显示 MMP 家族成员的裂解带增加，这些成员被鉴定为明胶酶 A（MMP - 2）和明胶酶 B（MMP - 9）的酶原形式和活性形式。通过酪蛋白 - 纤溶酶原酶谱分析，后一种培养物还呈现出高分子量尿激酶型纤溶酶原激活剂（HMW - uPA）水平升高。用基质胶孵育从 OBCM 处理的 PC3 细胞纯化的囊泡，其比未处理的 PC3 细胞的囊泡更有效地裂解其成分。总体而言，这些发现表明成骨细胞产生能够改变前列腺癌细胞侵袭能力的因子，增加脱落囊泡及其相关裂解酶的数量。
