Griegel S, Hong C, Frötschl R, Hülser D F, Greger V, Horsthemke B, Rajewsky M F
Institut für Zellbiologie (Tumorforschung), Universitätsklinikum Essen, FRG.
Int J Cancer. 1990 Jul 15;46(1):125-32. doi: 10.1002/ijc.2910460123.
Retinoblastoma (RB), an intraocular childhood tumor occurring in a hereditary (mostly bilateral) or non-hereditary (unilateral) form, is associated with the inactivation of both alleles of a putative tumor suppressor gene (RB-I) located on chromosome 13q14. Both the process of RB development and the biological characteristics of RB cells are as yet poorly understood. We have established 7 new RBL lines (RBL13, RBL14, RBL18 and RBL30, derived from unilateral RB; and RBL7, RBL15 and RBL20, derived from bilateral RB). Southern blot analyses of restriction fragment length polymorphisms in DNA samples from 6 cell lines revealed loss of constitutional heterozygosity at one or several polymorphic loci on chromosome 13 in 4 cases. Gross deletions involving the RB-I locus and amplification of the N-myc gene were not detected in any of the RBL lines. The phenotypic properties of the RBL lines were analyzed in comparison with cells from the original RB tumors, with 4 RB lines established by others (RB383, RB355, RB247C3 and Y79) and with the adenovirus-EIA-transformed human retinoblast line HER-Xhol-CC2. It was found that RB tumors consist of phenotypically heterogeneous cell subpopulations with varying nutrient requirements and differentiation potential in vitro. All cell lines showed the typical characteristics of established ("immortalized") cells. In some cases, cells from original RB tumors or cell lines were able to form colonies when cell aggregates of 2-10 cells were suspended in semi-solid agar medium; however, anchorage-independent colonies never developed from single cells. Cell lines RBL13, RBL18, RB247C3, RB355, RB383 and Y79 were tested for invasion into embryonic chick heart fragments in vitro and found to be non-invasive. None of the RBL or RB lines were tumorigenic in nu/nu (T-) mice. Y79 cells (propagated in culture for many years) exhibited properties distinctly different from those of the other cell lines, and thus cannot be considered phenotypically representative of RB cells.
视网膜母细胞瘤（RB）是一种发生于儿童期的眼内肿瘤，有遗传性（多为双侧性）和非遗传性（单侧性）两种形式，与位于13q14染色体上的一个假定的肿瘤抑制基因（RB-1）的两个等位基因失活有关。目前，人们对RB的发生过程以及RB细胞的生物学特性了解甚少。我们已经建立了7个新的RB细胞系（RBL13、RBL14、RBL18和RBL30，源自单侧RB；以及RBL7、RBL15和RBL20，源自双侧RB）。对6个细胞系的DNA样本进行限制性片段长度多态性的Southern印迹分析显示，4例中13号染色体上的一个或几个多态性位点出现了结构杂合性缺失。在任何RBL细胞系中均未检测到涉及RB-1位点的大片段缺失和N-myc基因的扩增。将RBL细胞系的表型特性与原始RB肿瘤细胞、其他实验室建立的4个RB细胞系（RB383、RB355、RB247C3和Y79）以及腺病毒-EIA转化的人视网膜母细胞系HER-Xhol-CC2进行了比较分析。结果发现，RB肿瘤由表型异质性的细胞亚群组成，这些亚群在体外对营养的需求和分化潜能各不相同。所有细胞系均表现出已建立的（“永生化”）细胞的典型特征。在某些情况下，当将2-10个细胞的细胞聚集体悬浮于半固体琼脂培养基中时，原始RB肿瘤细胞或细胞系的细胞能够形成集落；然而，单细胞从未形成非锚定依赖性集落。对细胞系RBL13、RBL18、RB247C3、RB355、RB383和Y79进行了体外侵袭鸡胚心脏组织块的检测，发现它们均无侵袭性。没有一个RBL或RB细胞系在裸鼠（nu/nu，T-）中具有致瘤性。Y79细胞（已在培养中传代多年）表现出与其他细胞系明显不同的特性，因此不能被视为RB细胞的表型代表。
