反义内含子长链非编码RNA(Ai-lncRNA)的生物学功能尚不清楚。同时,紫杉醇耐药的癌症患者在临床上的治疗选择有限。然而,在人类癌症中,Ai-lncRNA可能参与紫杉醇的敏感性尚不清楚.
对33个乳腺样本进行全转录组测序以鉴定Ai-lncRNAEGOT。接下来,研究了EGOT在调节紫杉醇敏感性中的作用.此外,详细研究了EGOT通过RNA-RNA和RNA-蛋白质相互作用上调ITPR1表达而增强自噬对紫杉醇细胞毒性的机制.此外,还通过免疫共沉淀和染色质免疫沉淀研究了EGOT表达的上游转录调控.最后,我们队列中的临床乳腺标本,TCGA和ICGC用于验证EGOT在增强紫杉醇敏感性中的作用。
EGOT通过上调ITPR1的表达促进自噬体的积累,从而使细胞对紫杉醇的毒性敏感。机械上,一方面,EGOT通过形成pre-ITPR1/EGOTdsRNA上调ITPR1水平,该dsRNA诱导pre-ITPR1积累以顺式增加ITPR1蛋白表达。另一方面,EGOT通过外显子1中EGOT区段2(324-645个核苷酸)中的两个结合基序招募hnRNPH1以增强反式pre-ITPR1的可变剪接。此外,EGOT受胁迫条件的转录调节。最后,EGOT表达通过评估癌症样本增强紫杉醇敏感性。
这些发现拓宽了对Ai-lncRNAs生物学功能的全面理解。适当调节EGOT可能是增强癌症治疗中紫杉醇敏感性的新型协同策略。
The biology function of antisense intronic long noncoding RNA (Ai-lncRNA) is still unknown. Meanwhile, cancer patients with paclitaxel resistance have limited therapeutic options in the clinic. However, the potential involvement of Ai-lncRNA in paclitaxel sensitivity remains unclear in human cancer.
Whole transcriptome sequencing of 33 breast specimens was performed to identify Ai-lncRNA EGOT. Next, the role of EGOT in regulation of paclitaxel sensitivity was investigated. Moreover, the mechanism of EGOT enhancing autophagy sensitizes paclitaxel cytotoxicity via upregulation of
ITPR1 expression by RNA-RNA and RNA-protein interactions was investigated in detail. Furthermore, upstream transcriptional regulation of EGOT expression was also investigated by co-immunoprecipitation and chromatin immunoprecipitation. Finally, clinical breast specimens in our cohort, TCGA and ICGC were applied to validate the role of EGOT in enhancing of paclitaxel sensitivity.
EGOT enhances autophagosome accumulation via the up-regulation of
ITPR1 expression, thereby sensitizing cells to paclitaxel toxicity. Mechanistically, on one hand, EGOT upregulates
ITPR1 levels via formation of a pre-
ITPR1/EGOT dsRNA that induces pre-
ITPR1 accumulation to increase
ITPR1 protein expression in cis. On the other hand, EGOT recruits hnRNPH1 to enhance the alternative splicing of pre-
ITPR1 in trans via two binding motifs in EGOT segment 2 (324-645 nucleotides) in exon 1. Moreover, EGOT is transcriptionally regulated by stress conditions. Finally, EGOT expression enhances paclitaxel sensitivity via assessment of cancer specimens.
These findings broaden comprehensive understanding of the biology function of Ai-lncRNAs. Proper regulation of EGOT may be a novel synergistic strategy for enhancing paclitaxel sensitivity in cancer therapy.