MIR340

Summary

MIR340 (microRNA 340, HGNC:31777) is a microRNA gene on chromosome 5q35.3.

microRNAs (miRNAs) are short (20-24 nt) non-coding RNAs that are involved in post-transcriptional regulation of gene expression in multicellular organisms by affecting both the stability and translation of mRNAs. miRNAs are transcribed by RNA polymerase II as part of capped and polyadenylated primary transcripts (pri-miRNAs) that can be either protein-coding or non-coding. The primary transcript is cleaved by the Drosha ribonuclease III enzyme to produce an approximately 70-nt stem-loop precursor miRNA (pre-miRNA), which is further cleaved by the cytoplasmic Dicer ribonuclease to generate the mature miRNA and antisense miRNA star (miRNA*) products. The mature miRNA is incorporated into a RNA-induced silencing complex (RISC), which recognizes target mRNAs through imperfect base pairing with the miRNA and most commonly results in translational inhibition or destabilization of the target mRNA. The RefSeq represents the predicted microRNA stem-loop.

Source: NCBI Gene 442908 — RefSeq curated summary.

At a glance

• Gene type: non-coding (miRNA) — no protein product; not a drug target. Variant/disease associations are omitted (they would be positional, from an overlapping protein-coding gene).

Identifiers

Gene identifiers

Field	Value
HGNC ID	HGNC:31777
Approved symbol	MIR340
Name	microRNA 340
Location	5q35.3
Locus type	RNA, micro
Status	Approved
Aliases	hsa-mir-340
Ensembl gene	ENSG00000198995
Ensembl biotype	miRNA
Entrez	442908
RNAcentral	URS000075C604 — miRNA, 95 nt, 7 organism(s)

Gene structure

Transcript identifiers

Ensembl transcripts: 1 — 1 miRNA

ENST00000362125

RefSeq mRNA: 0 — MANE Select: None

Canonical transcript exons

ENST00000362125 — 1 exons

Exon	Start	End
ENSE00001436888	180015303	180015397

Expression profiles

Bgee: expression breadth broad, 74 present calls, max score 84.84.

Top tissues by expression

74 total, by Bgee expression score (0-100, higher = more expressed):

Tissue	Anatomy ID	Expression score	Quality
calcaneal tendon	UBERON:0003701	84.84	gold quality
adrenal tissue	UBERON:0018303	79.34	gold quality
blood	UBERON:0000178	79.30	gold quality
endometrium	UBERON:0001295	76.13	gold quality
adult mammalian kidney	UBERON:0000082	75.03	gold quality
islet of Langerhans	UBERON:0000006	74.94	gold quality
bone marrow	UBERON:0002371	74.82	gold quality
monocyte	CL:0000576	74.36	gold quality
lung	UBERON:0002048	74.34	gold quality
placenta	UBERON:0001987	74.26	gold quality
kidney	UBERON:0002113	74.18	gold quality
stomach	UBERON:0000945	71.88	gold quality
right ovary	UBERON:0002118	71.03	gold quality
gastrocnemius	UBERON:0001388	70.85	gold quality
body of pancreas	UBERON:0001150	69.07	gold quality
body of stomach	UBERON:0001161	68.85	gold quality
heart	UBERON:0000948	68.61	gold quality
corpus callosum	UBERON:0002336	68.49	gold quality
lower esophagus muscularis layer	UBERON:0035833	68.46	gold quality
heart left ventricle	UBERON:0002084	68.44	gold quality
liver	UBERON:0002107	68.40	gold quality
right atrium auricular region	UBERON:0006631	68.40	gold quality
right lobe of liver	UBERON:0001114	68.35	gold quality
intestine	UBERON:0000160	68.18	gold quality
ectocervix	UBERON:0012249	67.86	gold quality
body of uterus	UBERON:0009853	67.81	gold quality
left coronary artery	UBERON:0001626	67.51	gold quality
hypothalamus	UBERON:0001898	67.22	gold quality
colon	UBERON:0001155	67.09	gold quality
muscle layer of sigmoid colon	UBERON:0035805	66.95	gold quality

Single-cell (SCXA)

Detected in 1 experiment(s), a significant marker in 0.

Experiment	Marker?	Max mean expression
E-ANND-3	no	0.33

Regulation

Is transcription factor: no

Literature-anchored findings (GeneRIF, showing 40)

• miR-340 may play an important role in breast cancer progression, and should be further evaluated as a novel biomarker for breast cancer metastasis and prognosis, and potentially a therapeutic target (PMID:21692045)
• MiR340* and miR624* were confirmed to be upregulated in patients with Coronary artery disease as compared to healthy controls. (PMID:22022480)
• miRNAs (miR-124, miR-137 and miR-340) impair colorectal cancer growth by regulating alternative splicing of the PKM gene (PMID:22895557)
• miR-340 acts as a tumor suppressor and its downregulation in tumor tissues may contribute to the progression and metastasis of OS through a mechanism involving ROCK1 (PMID:23872151)
• The downregulation of miR-340 was more frequently in osteosarcoma tissues with positive metastasis and poor response to pre-operative chemotherapy. (PMID:24398981)
• Data suggest that miR-340 in bone marrow may play an important role in regulating the metastasis cascade of colorectal cancer. (PMID:24448820)
• The significant downregulation of RhoA protein and mRNA expression after UVB irradiation and the modulation of miR-340 expression suggest a key role for miR-340 in regulating UVB-induced dendrite formation and melanosome transport. (PMID:24980435)
• miR-340 inhibits the tumorigenic phenotype of melanoma cells. (PMID:25043973)
• miR-340 controls p27 at both translational and posttranslational levels in non-small cell lung cancer (PMID:25151966)
• MicroRNA-340-mediated degradation of MITF mRNA is inhibited by CRD-BP. (PMID:25414259)
• Lower expression of miR-340 is involved in the development of cisplatin resistance in hepatocellular carcinoma cell line, at least partly due to regulating Nrf2-dependent antioxidant pathway. (PMID:25556489)
• shRNA-mediated silencing of PLAT in glioma-initiating cells phenocopied the effects of miR340 overexpression in vitro (PMID:25627976)
• results demonstrate that miR-340 plays a tumor-suppressive role in glioblastoma and may be useful as a diagnostic biomarker and/or a therapeutic avenue for glioblastoma (PMID:25817794)
• MiR-340 inhibited cell growth and motility and induced the terminal differentiation through modulation of hallmarks of glioma cells. (PMID:25831237)
• PSAT1 was identified as a direct target of miR-340. (PMID:26316084)
• Decreased miR-340 expression may contribute to the development and progression of prostate cancer through a mechanism that involves HMGN5. (PMID:26394192)
• findings suggest that miR-340 might act as molecular switch that contributes to regulation of glycolysis in OSCC by regulating Glut1 expression. (PMID:26541225)
• This is the first study showing the relationship between miR-340-5p and expression of ABCB5 in melanoma cells (PMID:26554847)
• miR340 plays an important role in breast cancer progression (PMID:26573744)
• miR-340 directly targeted EZH2 expression and inhibited progression of laryngeal squamous carcinoma. (PMID:26656176)
• Our findings suggest that miR-340 may function as a novel tumor suppressor in prostate cancer (PMID:26718483)
• MiR-340 can promote tumor cell growth and reduce cell apoptosis effectively in human gastric cancer cell line (PMID:26722508)
• The important role of miR-340 as a pivotal regulator of breast cancer metastasis. (PMID:26758430)
• Results show that NRAS mRNA is a direct target of microRNA miR-340. (PMID:26799668)
• Low miR340 expression is associated with breast cancer progression. (PMID:27036021)
• MiRNA-340 acts as an anti-oncogene in endometrial carcinoma cell line RL 95-2 by inhibition of tumor cell proliferation and induction of apoptosis. (PMID:27153225)
• MiR-340 mimic arrested cell cycle progression and promoted apoptosis of Ovarian Cancer Cells by decreasing NF-kappa B1. (PMID:27160777)
• The results showed a decline in the expression of SOX2, P16 and P27 after miR-340 over-expression in triple-negative breast cancer cells, whereas an increase in the expression of cyclin A2, CDK2, SOX17, P18, SMAD 4 and RB was observed. (PMID:27229858)
• CCNG2 knockdown eradicated the effects of miR-340 silencing. (PMID:27374211)
• Data suggest that miRNA-340/429, which targeted IL-4, might be a potential approach for cancer treatment. (PMID:27895317)
• miR-340 suppressed HCC cell proliferation and invasion by regulating the JAK1/STAT3 pathway (PMID:27998770)
• Overexpression of miR-340 significantly reduced cell viability and proliferation (P<0.01), and induced cell apoptosis (P<0.01) of SGC-7901. miR-340 elevated the protein level of cell cycle inhibitor p27, but did not affect the level of p21. Apoptosis-related factors pro-CASP3, cleaved-CASP3, and BAX were promoted, and BCL2 was inhibited by miR-340. miR-340 also suppressed the phosphorylation of AKT. (PMID:28057912)
• Intratumoral expression of miR-7 and miR-340 prior to neoadjuvant chemotherapy could be used to predict pCR and a profile of miR-7(low) or miR-340(high) identified patients unlikely to achieve pCR who might benefit from alternative treatment options including earlier surgery. (PMID:28181130)
• miR-340 acts as a tumor suppressor in colorectal cancer and is involved in the chemoresistance of colorectal cancer. (PMID:28682430)
• HIF-1alpha, which suppressed miR-340-5p promoter activation through HRE motifs, was induced by FA. The induction of b-catenin signaling by FA was consistent with an enhancement in osteogenesis of FA-treated MSC, which could be attenuated by miR-340-5p overexpression. Analysis of the signaling networks induced by FA reveals that hypoxia may promote the osteogenic program in mesenchymal stem cells via a novel microRNA pa… (PMID:28764862)
• The results of the present study revealed that miR340 serves a tumor suppressor role by influencing the proliferation, apoptosis, migration and invasion of HCC cell lines, which may be explained by the downregulation of SKP2 by miR340. (PMID:28944918)
• NT5E-targeting miRNAs (miR-30b and miR-340) function as tumor suppressors (PMID:29155108)
• Low miR340 expression is associated with gastric tumorigenesis. (PMID:29234151)
• identified four miRNAs, miR-19, miR-340, miR-374 and miR-542 that bind to the 3’-UTR of the MID1 mRNA. These miRNAs not only regulate MID1 expression but also mTOR signaling and translation of disease associated mRNAs and could therefore serve as potential drugs for future therapy development (PMID:29293623)
• Compared with the control, miR-340 was significantly lower in the serum of hepatocellular carcinoma patients (p<0.01). miR-340 was lower in HCC tissues than in adjacent; however, DcR3, TGF-beta1 and Smad2 were higher. (PMID:29311025)

Cross-species orthologs

2 orthologs

Organism	Symbol	Gene ID
mus_musculus	Mir340	ENSMUSG00000065417
rattus_norvegicus	Mir340-2	ENSRNOG00000065444

Protein

Non-coding RNA — no protein product; not a drug target.

Function

No curated pathway, Gene-Ontology, or interaction data.

Disease & clinical

No curated disease, variant, or cancer-driver associations.

Drugs & pharmacology

No drug or pharmacology data — not an established drug target.