microRNA与黑素瘤

microRNA是一种大小约22个核苷酸的非编码单链小RNA分子,参与细胞增殖、分化、凋亡等多种重要细胞活动的调控.近来研究发现,microRNA具有癌基因或抑癌基因样作用,在人类恶性肿瘤的发生、发展中起重要作用.目前已发现数种microRNA在黑素瘤细胞表达异常,其中microRNA-221和microRNA-222在黑素瘤中表达升高,可以通过下调p27Kip1/CDKN1B和c-KIT受体两条通路来促进黑素细胞的恶性转化,在黑素瘤中发挥癌基因样作用.而microRNA-137、-34a、-199a和let-7家族成员let-7a、let-7b等,分别下调相应的靶基因,在黑素瘤中发挥抑癌基因样的作用.microRNA对黑素瘤相关基因的表达调控研究,不仅探讨早期黑素瘤发生的新的调节机制,而且为将来靶向治疗开辟道路.

microRNAs and melanoma

microRNAs (miRNAs) are non-coding single-stranded RNAs containing about 22 nucleotides that regulate a variety of cellular processes including cell proliferation, differentiation, apoptosis, etc. Recent studies have suggested an important role of miRNAs in the initiation and progression of human malignancies. Some miRNAs may function as oncogenes or tumor suppressors. Changes in the expression of several miRNAs have been observed in melanoma cell lines. For example, the expressions of miRNA-221 and miRNA-222 are reported to be upregulated in melanoma, and they can accelerate malignant transformation of melanoma cells by downregulating p27Kip1/CDKN1B and c-KIT receptor pathways. Therefore, miRNA-221 and miRNA-222 may function as oncogenes in melanoma. In contrast, miRNA-137, miRNA-34a, miRNA-199a and let-7 family members (such as let-7a and let-7b) can downregulate the expression of relevant target genes and they function as tumor suppressors in melanoma. To study the regulation of melanoma-associated gene expression by miRNAs would point to new regulatory mechanism of early melanoma initiation and blaze a way in targeted therapy in future.