长链非编码RNA lncR-RP11作为ceRNA调控Kras表达在胰腺癌中作用及机制研究

Overexpression of Kras plays pivotal roles in pancreatic cancer. Studies indicate that long non-coding RNA (lncRNA) may act as competing endogenous RNA (ceRNA) to inhibit the combination between miRNA and mRNA. Basing on our previous study about miRNA, we applied lncRNA microarray to find that lncR-RP11 obviously upregulates in pancreatic cancer and positively correlates to the expression of Kras. The microRNA software predicted that both RP11 and 3' UTR of Kras mRNA might combine to the miR-3923. Hence, we hypothesis that RP11 may competitively combine with miR-3923 and then inhibit its combination with Kras 3' UTR, which may upregulate the expression of Kras. The present study will analyze correlation among the expression of RP11, miR-3923, Kras and clinical characteristics. The combination of miR-3923 with RP11 and K-ras is verified by dual luciferase reporter array. After regulation of RP11/miR-3923, the Kras expression and malignant behavior of pancreatic cancer cells will be observed both in vitro and in vivo. The present study is to discover novel mechanism for Kras regulation and function of lncR-RP11 in pancreatic cancer, and further provide new sight in role of lncRNA in tumorigenesis.

Kras过表达与胰腺癌密切相关。最近发现长链非编码RNA(lncRNA)可作为竞争性内源RNA(ceRNA)抑制miRNA与靶mRNA结合而上调其表达。前期lncRNA芯片发现胰腺癌高表达lncRNA-RP11，且与Kras表达正相关；生物信息分析RP11与Kras mRNA均可结合miR-3923。课题设想RP11竞争性抑制Kras mRNA与miR-3923结合，上调Kras表达。 拟检测RP11/miR-3923/Kras表达与临床特征相关性，双荧光素酶检测RP11与Kras竞争结合miR-3923；调控RP11/ miR-3923表达，体外及体内观察Kras及胰腺癌生物学行为改变。课题整合高通量芯片与生物信息分析，从ceRNA调控Kras表达角度探讨RP11在胰腺癌中作用及机制，为胰腺癌防治提供新靶点与新策略，有助于深入理解非编码RNA与mRNA之间网络调控在肿瘤发生发展中作用。

近来研究发现长链非编码RNA(lncRNA)在肿瘤发生发展中发挥重要作用，但其在胰腺癌中作用则未明确。本研究通过lncRNA芯片发现lncRNA-NUTF2P3-001 (RP11)在慢性胰腺炎及胰腺癌组织中表达显著上调，与K-ras mRNA表达相关。LncR-RP11表达与肿瘤低分化、分期进展、淋巴结及远处转移以密切相关。此外，高表达lncR-RP11的患者生存期较短。细胞学及动物实验研究发现抑制lncR-RP11表达显著抑制胰腺癌细胞K-ras表达，以及细胞增殖和侵袭能力。通过双荧光报告实验研究发现，lncR-RP11可作为竞争性内源RNA(ceRNA)抑制miR-3923与K-ras mRNA结合，进而上调K-ras表达。过表达miR-3923亦可显著抑制K-ras表达，以及细胞增殖和侵袭能力。此外，研究证实低氧微环境通过HIF-1α与lncR-RP11的启动子结合，促进lncR-RP11表达。分析胰腺癌样本证实，lncR-RP11与K-ras表达正相关。课题整合高通量芯片与生物信息分析，从ceRNA调控Kras表达角度探讨RP11在胰腺癌中作用及机制，为胰腺癌防治提供新靶点与新策略，有助于深入理解非编码RNA与mRNA之间网络调控在肿瘤发生发展中作用。