The Role of Non-Coding RNA Editing in MET Signaling in NSCLC

项目总结 肺癌是美国癌症相关死亡的主要原因，尽管在创造 在新的治疗方法中，大多数肺癌患者对转移疾病产生抵抗力并死亡。这个 表皮生长因子受体(EGFR)是一种受体酪氨酸激酶(RTK)，在肺组织中经常发生突变 癌症(10-50%)。已经开发了几种EGFR抑制剂来减轻突变的转化效应 EGFR。例如，吉非替尼和奥西美替尼是用于治疗EGFR的酪氨酸激酶抑制剂(TKI)。 非小细胞肺癌(NSCLC)。不幸的是，尽管患者最初对 这些药物的快速获得性耐药性主要是因为新的基因改变，包括 扩增肝细胞生长因子受体(MET)。 腺苷到肌苷(A-to-I)RNA编辑代表细胞中所有RNA编辑事件的90%，并调节 信使核糖核酸序列、功能、降解和结构。在编码和非编码中都观察到了RNA编辑 编码基因，包括miRs。此外，编码RNA编辑失调最近被认为与 癌症表型和耐药性，包括对TKIs的耐药性。 最近对人类基因组的高通量询问使得miR编辑的鉴定成为可能 癌症方面的放松管制。然而，编辑的非编码RNA(即miRs)在肺癌中的生物学影响 进展和耐药性在很大程度上仍不清楚。 我们初步确定在肺癌组织中miR-411-5p第5位的A-to-I编辑减少 病人。我们确定ed.miR-411-5p对ERK1/2通路产生负面影响，直接达到靶点，并 改变非小细胞肺癌细胞系对TKI的耐药性。此外，据报道，MET在转录上调节 MiR-222的表达。我们还发现miR-222针对的是ADAR成员ADAR2 蛋白质家族，负责前信使核糖核酸和非编码RNA A-to-I编辑。ADAR2还导致A-to-I编辑 MIR，包括MIR-411-5P。我们发现ADAR2在肺癌组织中表达下调，并对TKI耐药 组织和细胞系与miR-222表达呈负相关。 我们假设miR编辑失调在肺癌的病理生物学中起作用。因此，我们的目标是 全球评估ed.miR-411-5p对非小细胞肺癌进展和TKI耐药的影响。然后，我们 也打算由RNA序列进行调查。如果ed.miR-411-5p通过诱导ADAR2的表达和活性 Met、ERK1/2和miR-222信号转导抑制与发现新的转录后转录 调节肺癌进展和耐药性的机制。

PROJECT SUMMARY Lung cancer is the primary cause of cancer-related deaths in the U.S. Despite encouraging progress in creating new therapeutics, most lung cancer patients develop resistance and succumb to metastatic disease. The epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase (RTK) that is frequently mutated in lung cancer (10-50%). Several EGFR inhibitors have been developed to mitigate the transformative effects of mutant EGFR. For example, gefitinib and osimertinib are tyrosine kinase inhibitors (TKIs) used for treating EGFR- mutated non-small cell lung cancer (NSCLC). Unfortunately, despite the initial responsiveness of patients to these drugs, a rapidly acquired resistance occurs mainly because of new genetic alterations, including amplification of the hepatocyte growth factor receptor (MET). Adenosine to Inosine (A-to-I) RNA editing represents 90% of all the RNA editing events in the cell and regulates mRNA sequence, function, degradation, and structure. RNA editing has been observed in both coding and non- coding genes, including miRs. Furthermore, coding RNA editing dysregulation has been recently associated with cancerous phenotype and drug resistance, including against TKIs. Recent high throughput interrogation of the human genome has allowed for the identification of miR editing deregulation in cancer. However, the biological impact of edited non-coding RNAs (i.e., miRs) in lung cancer progression and drug resistance remains largely unknown. We preliminarily identified a reduction of A-to-I editing in position 5 of miR-411-5p in the tissues of lung cancer patients. We determined that ed.miR-411-5p negatively affects the ERK1/2 pathway, directly targets MET, and alters TKI drug resistance in NSCLC cell lines. Furthermore, it is reported that MET transcriptionally regulates the expression of miR-222. We have also found that the miR-222 targets ADAR2, a member of the ADAR proteins family, responsible for pre-mRNA and non-coding RNA A-to-I editing. ADAR2 also induces A-to-I editing in miRs, including miR-411-5p. We found that ADAR2 is downregulated in lung cancer tissues and TKI resistant tissue and cell lines and anticorrelates with miR-222 expression. We hypothesize that miR editing dysregulation contributes to the pathobiology of lung cancer. Therefore, we aim to globally evaluate the impact that ed.miR-411-5p has on NSCLC progression and TKI resistance. Then, we also intend to investigate by RNA seq. if the ed.miR-411-5p induces ADAR2 expression and activity through MET, ERK1/2, and miR-222 signaling repression with the scope of uncovering new post-transcriptional mechanisms that regulate lung cancer progression and drug resistance.