MIR33B is a microRNA with a tumor suppressor role, typically under-expressed in multiple myeloma (MM) patients [PMC5721125]. It is located in the intron 17 of the SREBF-1 gene locus in humans, and this gene is absent in rodents [PMC3639327]. When overexpressed, MIR33B inhibits tumor growth and enhances survival in MM xenograft mouse models by inducing apoptosis through the suppression of proto-oncogene PIM-1 [PMC5721125][PMC7236745[PMC7236745]. MIR33B expression is influenced by lipid metabolism and can be regulated by statins like pitavastatin, which prevents its suppression by oxidized low-density lipoprotein (oxLDL) [PMC4945056]. It also plays a role in reducing metastasis and the epithelial-mesenchymal transition phenotype, with its silencing reversing cordycepin-mediated effects [PMC4496401]. Additionally, MIR33B expression can be epigenetically suppressed by PRMT5, which promotes lymphoma cell growth and survival through silencing tumor-suppressing miRNAs including MIR33B [PMC10147102][PMC10044308][PMC10044308]. In metabolic contexts, MIR33B has been associated with lipid homeostasis regulation alongside its host gene SREBF-1 and has been found to be upregulated in familial hypercholesterolemia cases, correlating with LDL cholesterol levels [PMC5113745][PMC3359973][PMC5085653[PMC3359973][PMC5085653].
----- --- - c c - UU g g
gc gggc ggc ccg gG UGCAUUGCUG GCAUUGCac ugu u
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cg cccg ccg ggC CC ACGUGACGGC CGUGACgug gcg a
cacca guc g a - G UC g g
| Name | Accession | Chromosome | Start | End | Strand | Confidence |
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| Accession | MIMAT0003301 |
| Description | Homo sapiens hsa-miR-33b-5p mature miRNA |
| Sequence | 16 - GUGCAUUGCUGUUGCAUUGC - 35 |
| Evidence |
experimental
SAGE [1], cloned [2] |
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| Accession | MIMAT0004811 |
| Description | Homo sapiens hsa-miR-33b-3p mature miRNA |
| Sequence | 54 - CAGUGCCUCGGCAGUGCAGCCC - 75 |
| Evidence |
experimental
cloned [2] |
| Database links |
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| Predicted targets |
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