Small nucleolar RNA SNORD99 (SNORD99)

Small nucleolar RNA SNORD99 is a non-coding RNA in the C/D box class of snoRNAs, primarily located in the nucleolus of eukaryotic cells[5]. These molecules function as guide RNAs, enabling site-specific 2'-O-methylation of other RNAs, particularly ribosomal RNA (28S rRNA at residue A2774)[5]. SNORD99 is primarily involved in the post-transcriptional modification of rRNA and snRNA, contributing to ribosome biogenesis and function[1][4][5]. Recent studies indicate an emerging role in cancer: SNORD99 is upregulated in endometrial cancer, where it enhances cell proliferation and migration by guiding methylation of genes involved in programmed cell death (pyroptosis), such as GSDMD, and potentially influencing cancer development[3]. SNORD99 (HBII-420) expression patterns have also been suggested as useful for tumor subtyping[2][3]. There are no established drug interactions or known safety concerns related to therapeutic targeting, and SNORD99 is not currently considered a direct therapeutic target (such as a receptor or enzyme), but it serves as a useful biomarker in research contexts.

Other names

HBII-420small nucleolar RNA, C/D box 99SNORD99