In vivo Invasion Assay and Enhancement of Differentiation of Low Passage Cultured Cells Derived from Human Non-Small Cell lung Carcinoma Using De-epithelialized Rat Tracheas Transplanted into Nude Mice.

利用裸鼠异种移植研究人类肿瘤能够考虑宿主反应，而在体外系统中这是不可能的。裸鼠提供了类似于人类的入侵环境；然而，S.C.传统的裸鼠异种移植的注射程序遇到了潜伏期长、肿瘤带菌率低的问题。本项目将低传代的人肺癌细胞系移植到裸鼠体内，以确定其生长行为和侵袭能力。将6株细胞接种于大鼠气管(5×10~(-5)个/气管)。细胞接种后，封闭气管，移植到裸鼠皮下。在一项平行实验中，将这些细胞系(1×10^6细胞)注入S.C.皮下移植瘤成瘤率仅为13%，潜伏期长达18周，3株细胞对周围…无侵袭性生长。更多的纸巾。在大鼠气管中，所有细胞株均在3周内增殖，其中4株在1~2周内呈侵袭性生长。生长在气管壁的细胞比生长在气管腔中的细胞具有更高的(~3H)胸腺嘧啶核苷标记指数和更大的异型性，如较大的核和突出的核仁。南卡罗来纳州肿瘤带菌率与气管壁侵袭性生长的发生率相关。最初携带这六种肿瘤的患者的生存也与该系统的侵袭潜力密切相关。在气管移植中，所有细胞株的分化程度都与原发病变相当或更高。而大多数细胞系在小鼠皮下组织中的分化程度较低。用来自鳞状细胞癌的细胞重新填充气管移植物的表面，最初由2到3个细胞厚的扁平细胞层排列。而用3例腺癌细胞重新种植的细胞，最初排列的是由立方形、圆形和柱状细胞组成的简单上皮。此后，这些细胞系分别呈现假复层形态、乳头状生长形态和筛状形态。在超微结构上，它们分别呈现纤毛支气管壁上皮细胞、非纤毛支气管壁上皮细胞和支气管杯状细胞的结构。这些结果表明，使用低传代细胞系的系统可以在接种后不久评估相对较少的细胞的侵袭潜力，可以作为临床可靠的生物侵袭试验。而且，使用该系统对培养细胞的组织学检查被认为有利于评估分化，因为它提供了在原发肿瘤或皮下直接细胞注射后形成的肿瘤中没有观察到的独特的增殖模式。较少

The investigation of human tumors using nude mouse xenograft is capable of taking into account the host reactions, whereas this is impossible in in vitro system. Nude mice offer an invasion environment similar to that of humans; however, s.c. injection procedures for conventional xenotransplantation into nude mice have encountered problems with regard to long latency periods low tumor take rates. In this project, human lung tumor-derived cell lines with low passage generation were transplanted into nude mice to determine their growth behavior and invasive potential. Six cell lines were inoculated into deepithelialized rat tracheas (5 x 10^5 cells/trachea). After cell inoculation, the tracheas were sealed and transplanted into the subcutis of nude mice. In a parallel experiment, these cell lines (1 x 10^6 cells) were injected s.c. In the subcutis, the tumor take rate was only 13% with a long latency period of 18 weeks, and 3 cell lines did not show any invasive growth to the surrounding … More tissue. In rat tracheas, all cell lines proliferated within 3 weeks, and 4 of them showed invasive growth to the tracheal wall within 1-2 weeks. Cells growing in the tracheal wall showed higher (^3H) thymidine labeling indexes and greater atypia, such as larger nuclei and prominent nucleoli, than those in the tracheal lumen. The s.c. tumor take rate correlated with the incidence of invasive growth to the tracheal wall. The survival of the patients originally bearing the six tumors also correlated closely with the invasive potential of this system. In tracheal transplants, all cell lines showed comparable or higher degree of differentiation than in the primary lesion. While most cell lines showed lower degree of differentiation in the mouse subcutis. The surfaces of tracheal transplants repopulated with the cells derived form squamous cell carcinomas were initially lined by a layer of flattened cells 2 to 3 cells thick. While those repopulated with the cells from 3 cases of adenocarcinoma were initially lined by simple epithelia consisted of cuboidal-, round-, and columnar-shaped cells, respectively. Thereafter, those cell lines revealed pseudostratified pattern, papillary growth pattern, and cribriform pattern, respectively. Ultrastructurally, they showed structures resembling ciliated bronchial epithelial cells, non-ciliated bronchiolar epithelial cells, and bronchial goblet cells, respectively.These results indicate that the system using low passage cell lines can evaluate the invasive potential shortly after the inoculation; of a relatively small number of cells and can be used as a clinically reliable biological invasion assay. And, histological examination of cultured cells using this system was considered to be advantageous for evaluation of differentiation because it provided unique proliferation patterns unobserved in primary tumors or tumors formed after subcutaneous direct cell injections. Less