多原发肺癌（MPLC）近年检出率明显增加。目前存在的主要问题是病因不明、无明确的诊断和治疗分子标记物。原癌基因Pim-1在多种肿瘤中激活通过调节磷酸化修饰参与肿瘤发生发展。项目前期全基因组测序一个MPLC家系发现Pim-1 Gly99Asp（33KD）为MPLC和多发结节患者中特异存在的新胚系突变，生信预测该位点具有致病性。本研究首先在DNA水平验证突变在散发MPLC中频率以及在RNA水平鉴定突变转录本；CRISPR-Cas9技术构建稳定敲除的细胞株、过表达Gly99Asp突变体研究生物学功能；磷酸化抗体芯片检测磷酸化修饰改变、RNAseq检测下游信号通路以明确作用机制。最后在大样本MPLC中探讨Pim-1 Gly99Asp与临床病理参数的关系。新胚系突变Pim-1 Gly99Asp的深入研究为我们揭示MPLC的病因提供线索，为进一步实现分子水平早期筛查和靶向治疗提供理论基础。

The function and mechanism of Pim-1 germline mutation in multiple primary lung cancer.The detection rate of multiple primary lung cancer (MPLC) has increased significantly in recent years. The main problem of MPLC is that the cause is unknown and there is no clear molecular markers for diagnosis and treatment. Whole-genome sequencing in a MPLC family found that Pim-1 Gly99Asp (33KD) is a new germline mutation specifically present in MPLC and multiple nodules, and bioinformatics predicts that the site is pathogenic.This study first verified the frequency of mutations in MPLC at the DNA level and identified mutant transcripts at the RNA level. CRISPR-Cas9 technology would use to construct a Pim-1 knock-out cell line and then the function of Pim-1 Gly99Asp mutation would be investigated with overexpression.The phosphorylated antibody chip detects changes in phosphorylation modification and RNAseq detects downstream signaling pathways to clarify the mechanism.The study of the new germline mutation Pim-1 Gly99Asp provides clues to reveal the etiology of MPLC and provides a theoretical basis for further early screening and targeted therapy at the molecular level.