Table 3.

Small nucleolar RNAs (snoRNAs) involved in tumor drug resistance.

SnoRNA	Mechanism	Biological function	Drug sensitivity	Related tumor type	Refs.
SNORD88C	Guiding 2'-O-methylation of 28S rRNA and upregulating SCD1	Inhibiting autophagy and promoting growth and metastasis	/	NSCLC	[53]
SNORD89	Activating the NOTCH1/c-MYC pathway	Promoting tumor cell proliferation and self-renewal ability	/	OV	[103]
SNORD1C	Activating the Wnt/β-catenin pathway	Promoting tumor cell proliferation, migration, and invasion	/	CRC	[105]
sdRNA-D19b	Targeting the 3'-UTR of CD44 genes	Promoting tumor cell proliferation and migration	Paclitaxel (−)	CRPC	[106]
SNORD3A, SNORA13, and SNORA2	Downregulating TOP2A and upregulating GADD45A	Promoting tumor development	DOX (−)	Human osteosarcoma	[111]
U3 snoRNA-related protein, RRP9/U3-55K	Activating the AKT signaling pathway	Promoting tumor growth	Gemcitabine (−)	Pancreatic cancer	[112]
SNORD33	Binding to MeCP2	Promoting tumor cell apoptosis	Cisplatin (+)	Triple-negative BRCA	[116]
SNORNA ACA11	Inhibiting NRF2 transcriptional activity	Promoting tumor development	DOX (−) and 5-FU (−)	MM	[122]
SNORA34	Deriving hsa-miR-1291 to target 3'-UTR of ABCC1	Promoting tumor cell sensitivity	DOX (+)	Pancreatic cancer	[125]

/: no data. (−) refers to downregulation and (+) refers to upregulation. SNORDs: C/D box snoRNAs; rRNA: ribosomal RNA; SCD1: stearoyl-CoA desaturase 1; NSCLC: non-small cell lung cancer; NOTCH1: neurogenic locus notch homolog protein 1; c-MYC: cellular MYC; OV: ovarian cancer; CRC: colorectal cancer; CD44: CD44 molecule; CRPC: castration-resistant prostate cancer; TOP2A: DNA topoisomerase II alpha; GADD45A: growth arrest and DNA damage inducible 45A; DOX: doxorubicin; RRP9: ribosomal RNA processing 9; AKT: protein kinase B; MeCP2: methyl cytosine-phosphate-guanine-binding protein 2; BRCA: breast cancer; NRF2: NF-E2-related factor 2; 5-FU: 5-Fluorouracil; MM: multiple myeloma; ABCC1: ATP binding cassette subfamily C member 1.