Extracellular matrix production by salivary gland tumor cells in three-dimensional culture system

腺样囊性癌的组织学特征是筛状外观，这是由于在每个肿瘤细胞巢中形成多个假囊腔所致。假性包囊被肿瘤细胞包围，充满基底膜分子等细胞外基质成分。我们已经证明这些基底膜分子是由独立于人涎腺腺样囊性癌建立的ACC2和ACC3细胞产生的。大量基底膜分子滞留在包括假性囊腔的间质空间中，表明基底膜基质对腺样囊性癌细胞的增殖是必不可少的。我们提出，腺样囊性癌细胞对周围神经、血管和骨骼肌的频繁侵袭可以被解释为与基底膜有亲和力。我们还发现，腺样囊性癌在…基质上附着、扩散和快速生长。更多的基底膜分子，使用人腺样囊性癌来源的ACC3细胞。然而，目前还不清楚假性囊泡是如何形成的，以及为什么这些特殊的结构通常与它们的生长有关。因此，我们计划建立一个腺样囊性癌细胞的三维培养系统，在这个系统中，可以在比单层培养系统更长的时间内分析肿瘤巢的结构。在这项研究中，我们成功地在胶原凝胶中培养了ACC细胞，并观察了肿瘤细胞集落中假性囊泡的形成过程。同时，我们检查了SCID小鼠的ACC2异种移植，并比较了移植物中形成的假性囊腔的性质与胶原凝胶培养中形成的假性囊腔的性质。在胶原凝胶培养中，细胞形成球状集落，瘤细胞巢内含有空泡结构，硫酸乙酰肝素蛋白多糖、III型胶原和IV型胶原以及纤维连接蛋白免疫反应阳性。在SCID小鼠体内移植的ACC2细胞生长形成肿瘤团块，并在其中形成假性包囊。结果表明，我们的胶原凝胶培养体系为ACC2细胞分泌特定的细胞外基质分子和形成假囊腔提供了生理条件。较少

Adenoid cystic carcinoma is histologically characterized by a cribriform appearance that results from formation of multi-pseudocystic spaces in each tumor cell nest. The pseudocysts are surrounded by tumor cells and are filled with extracellular matrix components such as basement membrane molecules. We have demonstrated that these basement membrane molecules were produced by ACC2 and ACC3 cells, established independently from human salivary adenoid cystic carcinomas.The retention of abundant basement membrane molecules in the stromal space that includes pseudocystic cavities suggests that basement membrane matrix is essential for proliferation of adenoid cystic carcinoma cells. We have proposed that their frequent invasion of peripheral nerves, blood vessels, and skeletal muscles can be interpreted to mean that adenoid cystic carcinoma cells have an affinity for basement membranes. We have also shown that adenoid cystic carcinoma dells attach, spread, and grow rapidly on matrices conta … More ining basement membrane molecules, using ACC3 cells of human adenoid cystic carcinoma origin. However, it is still unknown how pseudocysts are formed and why these particular structures are commonly associated with their growth. Thus, we planned to establish a three-dimension-culture system of adenoid cystic carcinoma cells in which the tumor nest architecture could be analyzed in a longer period than a monolayr culture system. In this study, we successfully cultured ACC cells in collagen gel and examined the process of pseudocyst formation in tumor cell colonies. At the same time, we examined xenografts of ACC2 in SCID mice and compared the nature of pseudocystic spaces formed in the transplants with that in the collagen gel cultures. In the collagen gel culture, the cells formed spherical colonies and the tumor cell nests contained vacuolar structures that were immunopositive for heparan sulfate proteoglycan, type III collagen and type IV collagen, and fibronectin. Transplants of ACC2 cells in SCID mice grew to form tumor messes in which pseudocysts were formed. The results indicate that our collagen gel culture system provides physiological conditions for ACC2 cells to secrete particular extracelluar matrix molecules and form pseudocystic spaces. Less