Density dependent polarized secretion of a prostatic epithelial cell line.
Density dependent polarized secretion of a prostatic epithelial cell line.
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前列腺上皮细胞系的密度依赖性极化分泌。
DOI：
10.1002/pros.2990200104
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
Onoda,M
中科院分区：
文献类型：
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作者：
Djakiew,D;Pflug,B;Delsite,R;Lynch,JH;Onoda,M
在各种细胞密度和培养条件下，研究了在双室中生长的PA‐III细胞的前列腺上皮片新合成的总蛋白和蛋白酶的极化分泌物（顶端/基底）。在无血清成分确定培养基（SFDM）中生长的PA‐III细胞形成形态极化的单层上皮细胞。这些细胞主要以顶端方向分泌35 S-蛋氨酸标记的总蛋白（顶端/基底比，4-8倍），在PA-III细胞单层的较低细胞密度下，顶端分泌的蛋白比例较小。在5%胎牛血清（FCS）中生长的PA‐III细胞在形态上呈鳞状，与间变性表型相当，并表现出极化总蛋白分泌的逆转（顶端/基底比，0.4-0.9倍），在较低的细胞密度下，基底方向分泌的总蛋白比例增加。由于在FCS中培养PA‐III细胞可能接近间变性表型，我们研究了这些细胞在不同细胞密度下的蛋白酶极化分泌，并将其与SFDM中培养的极化PA‐III细胞的蛋白酶分泌模式进行了比较。在FCS中生长的PA-III细胞的较低细胞密度下，蛋白酶分泌的极性被逆转，使得金属蛋白酶、组织型纤溶酶原激活剂和72 kD明胶酶主要以基底方向分泌，以及尿激酶和26 kD明胶酶，其或多或少相等地分泌到腔室的顶室和基底室中。另一方面，对于在SFDM中生长的PA-III细胞培养物，上述蛋白酶主要表现出顶端定向的分泌极性。这些结果表明，以极化结构丧失为特征的间变性表型也可能以极化分泌的功能丧失或反转为特征。极化分泌的这种损失或逆转的结果将是增加蛋白酶沿着细胞基底结构域的局部浓度，从而促进基底膜和间质组织在体内的降解。
The polarized secretions (apical/basal) of newly synthesized total protein and proteases from prostatic epithelial sheets of PA‐III cells grown in dual compartment chambers were investigated at various cell densities and culture conditions. PA‐III cells grown in a serum free defined medium (SFDM) form morphologically polarized monolayers of epithelial cells. These cells secreted their35S‐methionine labeled total protein in a predominantly apical direction (apical/basal ratio, 4–8 fold), with a lesser proportion of protein secreted apically at lower cell densities of the PA‐III cell monolayer. PA‐III cells grown in 5% fetal calf serum (FCS) are morphologically squamous, comparable to the anaplastic phenotype, and exhibited an inversion of polarized total protein secretion (apical/basal ratio, 0.4–0.9 fold), with an increased proportion of total protein secreted in a basal direction at lower cell densities. Since the culture of PA‐III cells in FCS may approximate the anaplastic phenotype we investigated the polarized secretion of proteases from these cells at various cell densities, and compared them with the secretory pattern of protease secretion from polarized PA‐III cells cultured in SFDM. At lower cell densities of the PA‐III cells grown in FCS the polarity of protease secretion was inverted such that metalloproteinases, tissue type plasminogen activator, and a 72 kD gelatinase were secreted in a predominantly basal direction, as well as urokinase and a gelatinase of 26 kD that were secreted more or less equally into the apical and basal compartments of the chambers. On the other hand, for cultures of PA‐III cells grown in SFDM the aforementioned proteases exhibited predominantly an apically directed polarity of secretion. These results suggest that the anaplastic phenotype characterized by a loss of polarized structure may also be characterized by a functional loss or inversion of polarized secretion. The consequences of such a loss or inversion of polarized secretion would be to increase the localized concentrations of proteases along the basal domain of cells thereby facilitating degradation of the basement membrane and interstitial tissue in vivo.