二、細胞實驗效果不錯，那動物實驗怎么做？
動物模型可在在腫瘤基礎性研究和抗腫瘤研究中發揮重要作用。結直腸癌研究中動物實驗主要分為三種類型：I自發結直腸癌模型；II誘導結直腸癌模型；III 移植結直腸癌模型。第I種主要是通過構建轉基因動物的方式實現，第II種則利用化學誘導劑誘導結直腸癌發生，但是誘導模型不便于研究腫瘤的侵襲和轉移能力；第III種將人類腫瘤組織或細胞直接接種于裸鼠進行研究。因裸鼠培育條件低，無毛，易于動態觀察腫瘤的生長狀態，且通過接種方式、部位的選擇可達到較滿意的轉移效果，因此目前多選擇裸鼠進行人結直腸癌細胞異體移植。
據數據統計，約30%的CRC患者發生肝臟轉移，這也是造成CRC患者死亡的最主要原因。今天我們就來著重看一看，結直腸癌轉移模型的構建吧。
注：增殖方向體內模型為裸鼠皮下成瘤，屬于腫瘤研究的常用模型，今天就不做詳細介紹了。實驗方法可參考前兩期肺癌、胃癌的總結文章。
三、體內外模型選好了，那么我的實驗需要使用哪種慢病載體對基因進行操作呢？
啟動子、熒光標記、抗性標簽是我們選擇載體需要考慮的三大要素。實驗不同，這些元件也需要相應變化。對于腸癌研究來說，人腸上皮細胞表面抗原基因A33啟動子，可作為組織特異性啟動子使用。按例祭出神圖一張，定制你的專屬載體，就是這么簡單！
參考文獻
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