Regulatory RNAs and the design of cancer therapy using RNA biotechnology

近年来研究发现，非编码RNA（regulatory RNA）在基因表达调控中起着重要作用。本研究旨在揭示microRNA在造血分化和白血病发生中的作用，阐明端粒酶活性的调控机制，并基于调控RNA的生理功能，利用RNA生物技术开发肿瘤诊断和治疗的新方法。结果表明：（1）siRNA敲低白血病融合基因后，白血病细胞自我更新活性下降，并诱导分化，提示该siRNA可用于白血病的治疗：（2）HL-60细胞向单核/巨噬细胞分化过程中MicroRNA表达动态变化; iii）获得了针对KRAS癌蛋白和其他癌症相关蛋白的RNA适体，这将成为癌症诊断和治疗新方法的种子; iv）端粒酶是使用固有RNA模板合成端粒DNA的专门逆转录酶。虽然编码催化亚基和模板RNA的基因已经被鉴定，但关于端粒酶如何在体内被募集到端粒的知之甚少。在这项研究中，我们试图在人类和裂殖酵母中以生物化学的方式鉴定这些因子。我们发现人类端粒酶对提取有很强的抵抗力。然而，我们分离的裂变酵母蛋白Poz 1和Ccq 1，负和正调节端粒酶。

It has recently been revealed that non-coding RNAs (regulatory RNAs) play important roles in the regulation of gene expression. The aims of this study were to manifest the role of microRNAs in hematopoietic differentiation and leukemogenesis, to clarify the regulation of telomerase activity, and to develop new methods for cancer diagnosis and therapy using RNA biotechnology on the basis of the physiological functions of regulatory RNAs. The following results were obtained: i) Knockdown of the leukemia fusion gene by siRNAs resulted in down-regulation of self-renewal activity and induction of differentiation, suggesting that these siRNAs can be used as therapeutics for leukemia; ii) MicroRNA expressions changed dynamically during differentiation to monocyte/macrophage in HL-60 cells; iii) RNA aptamers against the KRAS oncoprotein and other cancer-related proteins were obtained, which will become seeds for new methods of cancer diagnosis and therapy; iv) Telomerase is a specialized reverse transcriptase that synthesizes telomeric DNA using an intrinsic RNA template. Although the genes encoding the catalytic subunit and the template RNA have been identified, little is known about how telomerase is recruited to telomeres in vivo. In this study, we tried to biochemically identify such factors in human and fission yeast. We found that human telomerase is very resistant to extraction. However, we isolated fission yeast proteins Poz1 and Ccq1 that negatively and positively regulate telomerase.