Nicolson G L, Gallick G E, Dulski K M, Spohn W H, Lembo T M, Tainsky M A
Department of Tumor Biology, University of Texas M.D. Anderson Cancer Center, Houston 77030.
Oncogene. 1990 May;5(5):747-53.
The loss of intercellular junctional communication between rat 13762NF mammary carcinoma cells and their spontaneous metastatic potentials from the mammary fat pad show a high degree of correlation. We examined a stable, benign, completely junctionally coupled cell clone (MTC.4) of this system after calcium phosphate-mediated transfection with c-H-rasEJ/pSV2neo and control pSV2neo-containing plasmids. There was a good correlation between the copy numbers of c-H-rasEJ incorporated into MTC.4 cells and their contents of p21rasEJ; however, there was not always a correspondence between spontaneous metastatic potential and copy number of c-H-rasEJ or amount of p21rasEJ. After c-H-rasEJ/pSV2neo transfection, some MTC.4 cells lost intercellular junctional communication and became spontaneously metastatic, although some nonmetastatic transfectants also had low percentages of junctionally coupled cells. One of the control pSV2neo transfectants also became metastatic and lost intercellular junctional coupling, and calcium phosphate treatment itself resulted in increased growth rates at mammary fat pad sites and a marginal increase in incidence of spontaneous metastases, both of which preceded loss of intercellular junctional coupling in some cells. Examination of 12 subclones derived from two cloned transfectants, however, revealed a poor correlation between spontaneous metastatic potential and intercellular junctional coupling. The results suggest that loss of junctional communication between cells is often but not always associated with the progression of cells from benign to metastatic states.
大鼠13762NF乳腺癌细胞间连接通讯的丧失与其从乳腺脂肪垫的自发转移潜能之间呈现高度相关性。我们在用磷酸钙介导的方法将c-H-rasEJ/pSV2neo和含对照pSV2neo的质粒转染到该系统的一个稳定、良性、完全连接偶联的细胞克隆（MTC.4）后进行了研究。整合到MTC.4细胞中的c-H-rasEJ拷贝数与其p21rasEJ含量之间存在良好的相关性；然而，自发转移潜能与c-H-rasEJ拷贝数或p21rasEJ量之间并不总是对应。在用c-H-rasEJ/pSV2neo转染后，一些MTC.4细胞失去了细胞间连接通讯并变得自发转移，尽管一些非转移性转染细胞也有低比例的连接偶联细胞。其中一个对照pSV2neo转染细胞也变得具有转移性并失去了细胞间连接偶联，并且磷酸钙处理本身导致乳腺脂肪垫部位的生长速率增加以及自发转移发生率略有上升，这两者都先于一些细胞中细胞间连接偶联的丧失。然而，对来自两个克隆转染细胞的12个亚克隆的研究显示自发转移潜能与细胞间连接偶联之间的相关性较差。结果表明细胞间连接通讯的丧失常常但并非总是与细胞从良性状态向转移状态的进展相关。
