EGF信號:追蹤癌癥的路徑

表皮生長因子（EGF）家族是一組結構相關的蛋白質，通過靶細胞上的酪氨酸激酶受體調節細胞增殖、遷移和分化。EGF受體有一個細胞質酪氨酸激酶結構域，一個跨膜結構域和一個與EGF結合的細胞外結構域。配體與EGF受體結合導致其二聚、自磷酸化和激活。一旦被激活，EGF受體通過幾個蛋白質的磷酸化傳遞細胞內信號。

Ras被EGF受體激活是EGF信號轉導的重要組成部分。鳥嘌呤核苷酸交換因子SOS激活Ras, Ras進而觸發絲裂原激活蛋白(MAP)激酶通路。MAP激酶磷酸化轉錄因子，如激活蛋白1（AP-1;Fos-Jun二聚體）和Elk-1，導致細胞生長和發育。EGFR對Janus激酶(JAK)的磷酸化導致轉錄蛋白信號換能器和激活器(STATs)的激活，最終導致細胞的生長和分化。EGF信號的另一個關鍵方面涉及磷脂酶c - γ1 (PLCγ1)，它將PIP2裂解為IP3和DAG。IP3的產生導致內質網鈣的釋放，而DAG促進蛋白激酶C (PKC)的激活。PKC反過來磷酸化并激活轉錄因子Elk-1，導致細胞增殖。已知EGFR的突變影響其表達或活性，這使EGFR成為重要的藥物靶點。

該通路強調了EGF信號轉導的重要組成部分。

幾個重要的表皮生長因子信號通路

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