Blair D G, Cooper C S, Oskarsson M K, Eader L A, Vande Woude G F
Prog Clin Biol Res. 1983;119:79-90.
We have demonstrated that NIH 3T3 cells freshly transfected with either a cloned retroviral provirus or cell DNA derived from virally-transformed cells are able to induce tumors when injected subcutaneously into nude mice. Furthermore, cells transfected with DNA derived from at least three transformed human cell lines are able to induce tumors. These latter tumors contain human DNA sequences and DNA isolated from at least some of them is able to induce both foci and tumors in subsequent DNA transfection. Our data suggests that tumor induction by transfected 3T3 cells could serve as a powerful system for the selection of cells transformed by dominant cellular oncogenes. This method oviates the requirement that oncogenes induce clearly defined morphologically-transformed foci in order to be detected, and eliminates the need to maintain morphologically normal cells in tissue culture for many weeks, as well as the necessity of microscopically screning large numbers of tissue culture dishes. The tumors which arise in nude mice grow progressively, have been readily transplantable to other nude mice, and have been readily explantable into tissue culture. In addition, both DNA and RNA can be isolated directly from the mouse tumors to screen for the presence and expression of transfected sequences. We are currently examining other DNA samples from both human tumor-derived cell lines and primary human tumors to determine if this assay will detect and identify additional oncogenes. We are also studying the suitability of other normal cell lines as recipients in this assay, since cell lines which do not show readily discernible morphological transformation in monolayer culture may be suitable as tumor inducers following transfection. This assay should provide a convenient alternative method for detecting transforming genes and may help to increase the number of such sequence which can be identified and analyzed.
我们已经证明，用克隆的逆转录病毒原病毒或源自病毒转化细胞的细胞DNA新鲜转染的NIH 3T3细胞，皮下注射到裸鼠体内时能够诱发肿瘤。此外，用源自至少三种转化的人类细胞系的DNA转染的细胞也能够诱发肿瘤。这些后期形成的肿瘤含有人类DNA序列，从其中至少一些肿瘤中分离出的DNA在随后的DNA转染中能够诱发病灶和肿瘤。我们的数据表明，转染的3T3细胞诱发肿瘤可作为一种强大的系统，用于选择由显性细胞癌基因转化的细胞。这种方法避免了癌基因为了被检测而诱导出明确界定的形态转化病灶的要求，消除了在组织培养中维持形态正常的细胞数周的需要，以及显微镜下筛选大量组织培养皿的必要性。裸鼠体内产生的肿瘤会逐渐生长，很容易移植到其他裸鼠体内，也很容易移植到组织培养中。此外，可以直接从小鼠肿瘤中分离DNA和RNA，以筛选转染序列的存在和表达。我们目前正在检查来自人类肿瘤衍生细胞系和原发性人类肿瘤的其他DNA样本，以确定该检测方法是否能检测和鉴定出其他癌基因。我们还在研究其他正常细胞系作为该检测方法受体的适用性，因为在单层培养中未显示出易于识别的形态转化的细胞系，在转染后可能适合作为肿瘤诱导剂。该检测方法应能提供一种方便的替代方法来检测转化基因，并可能有助于增加可被识别和分析的此类序列的数量。
