荷人肺癌小鼠皮下移植瘤模型的建立及其生物学特性初探

Establishment and Its Biological Characteristics of Patient-derived Lung Cancer Xenograft Models

背景与目的为了更好地研究肺癌的治疗方法,建立起可靠的动物评价模型迫在眉睫。本研究的目的是研究建立肺癌原代组织块小鼠移植瘤模型的成熟方法,观察移植瘤的肿瘤生物学特性,在建模方法及基本特征等方面来证明该肿瘤模型的合理性和科学性,以期为肿瘤研究提供更有效的实验动物模型。方法取人新鲜完整肺癌组织块移植于NOD/SCID小鼠右侧前肢肩背部皮下,或经皮肺穿刺取得肿瘤小块移植于BALB/c裸小鼠肾包膜下。待皮下肿瘤增大,将其切下传代于裸小鼠右侧前肢肩背部皮下。观察移植瘤生物学特性,并取肿瘤行常规病理切片及CEA、细胞角蛋白、Ki67免疫组化检测,将原代肿瘤和移植瘤进行EGFR18-21外显子和K-Ras12,59外显子基因检测,采用流式细胞仪检测移植瘤细胞的细胞周期。结果本研究进行了11例肺癌组织的NOD/SCID小鼠和裸鼠建模,建成3例可多次成功传代的腺癌、小细胞肺癌和鳞癌模型。传代移植成功率高。荷瘤小鼠生长情况良好,生存期长。各代移植瘤模型的组织病理学及免疫组化表型、EGFR和K-Ras基因检测均与来源肺癌组织相一致。移植瘤细胞周期中S期延长,提示瘤细胞有增殖活性。结论本研究在国内首次利用新鲜的完整肺癌组织建成了荷肺癌NOD/SCID小鼠及裸鼠模型,并传代移植于裸鼠,建模成功率为27%。移植瘤较好地保留了人原发肺癌的恶性特征及组织病理学、生物学特性,是一种接近人体的肺癌模型,可为肺癌研究提供良好的实验平台。

Background and objective With the ongoing need to improve therapy for lung cancer, there has been an increasing interest in the development of reliable preclinical models to test novel therapeutics. The aim of this study is to estab- lish a patient-derived lung cancer xenograft model in mice and to observe the biological characteristics of xenografts. Methods Surgically resectected tumor specimens from patients with lung cancer were implanted in the subcutaneous layer of the NOD/ SCID mice. Cancer specimens of percutaneous lung biopsy by CT fluoroscopy were implanted into the subrenal capsule of nude mouse. The subcutaneous carcinoma was surgically removed when it grew to approximately 1.0 cm in diameter, and then re-transplanted into new nude mice. The growth process of transplanted tumor was observed. Expression of CEA, cytokeratin, and Ki67 were detected by immunohistochemistry. Mutations in the exons 18-21 of EGFR and exons 12,59 of K-ras of primary and xenograft tumors were examined. The cell cycle of xenograft tumor cells was analyzed by flow cytometry. Results Eleven cases were conducted for NOD/SCID mice and nude mice modelling. The patient-derived lung cancer xenografts have been established successfully, and the tumor could be passed to new nude mice, including No 2 model （adenocasinoma）, No. 3 model （small cell lung cancer）, and No. 5 model （squamous cell cancer）. High homogeneity was found between xenograft tumors and human lung cancer in histopathology, immunohistochemical phenotype, and EGFR, K-ras mutation status . The S-phase fraction of xenograft cell cycle was prolonged, which indicated that the xenografts remains highly proliferated. Conclusion The xenotransplantation models established for patient-derived lung cancer in immune deficient mice. The success rate is 27%. This model system displayed the biological characteristics of human lung cancer, suggesting that it may provide a stable, reliable, anduseful animal model in human lung cancer research.