Law PT, Ching AK, Chan AW, Wong QW, Wong CK, To KF, Wong NMiR-145 modulates multiple components of the insulin-like growth factor pathway in hepatocellular carcinoma. Carcinogenesis 33(6): 1-8
Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Shatin, NT, Hong Kong. Carcinogenesis
(Impact Factor: 5.33).
03/2012; 33(6):1134-41. DOI: 10.1093/carcin/bgs130
Profiling of microRNA expression in human cancers has highlighted downregulation of miR-145 as a common event in epithelial malignancies. Here, we describe recurrent underexpression of miR-145 in hepatocellular carcinoma (HCC) and the identification of a biological pathway by which miR-145 exerts its functional effects in liver tumorigenesis. In a cohort of 80 HCC patients, quantitative reverse transcription polymerase chain reaction corroborated reduced miR-145 expression in 50% of tumors, which also correlated with a shorter disease-free survival of patients. One HCC tumor analyzed with low endogenous miR-145 was propagated as cell line. This in vitro model HKCI-C2 maintained low miR-145 level and upon restoration of miR-145 expression, a consistent inhibitory effect on cell viability and proliferation was readily found. Flow cytometric analysis indicated that miR-145 re-expression could induce G(2)-M cell cycle arrest and apoptosis. Multiple in silico algorithms predicted that miR-145 could target a number of genes along the insulin-like growth factor (IGF) signaling, including insulin receptor substrate (IRS1)-1, IRS2 and insulin-like growth factor 1 receptor. We found protein expression of these putative targets was concordantly downregulated in the presence of miR-145. Luciferase reporter assay further verified direct target association of miR-145 to specific sites of the IRS1 and IRS2 3'-untranslated regions. Subsequent analysis also affirmed miR-145 modulation on the IGF signaling cascade by reducing its downstream mediator, namely the active β-catenin level. Taken together, our study shows for the first time the pleiotropic effect of miR-145 in targeting multiple components of the oncogenic IGF signaling pathway in HCC.
Available from: Pablo Letelier
- "In cancer, it has been reported to induce apoptosis through caspase 3, caspase 7 and PARP-1 in lung cancer cells , in maxillary sinus squamous cells , head and neck carcinoma cell carcinomas , bladder cancer  and renal cell carcinoma miR-1 and miR-145 in gallbladder cancer . In addition, miR-145 overexpression has also been reported as inducing apoptosis in oral squamous cell carcinoma , hepatocarcinoma  and acute myeloid leukemia . It has also been observed that mir-145 inhibits MDM2 mRNA, inducing apoptosis in cells of the head and neck carcinomas previously treated with cisplatin (interestingly this effect was not observed in untreated cells) . "
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ABSTRACT: The development of miRNA-based therapeutics represents a new strategy in cancer treatment. The objectives of this study were to evaluate the differential expression of microRNAs in gallbladder cancer (GBC) and to assess the functional role of miR-1 and miR-145 in GBC cell behavior. A profile of miRNA expression was determined using Dharmacon(TM) microarray technology. Differential expression of five microRNAs was validated by TaqMan reverse transcription quantitative-PCR in a separate cohort of 8 tumors and 3 non-cancerous samples. Then, we explored the functional role of miR-1 and miR-145 in tumor cell behavior by ectopic in vitro expression in the GBC NOZ cell line. Several miRNAs were found to be aberrantly expressed in GBC; most of these showed a significantly decreased expression compared to non-neoplastic tissues (Q value < 0.05). The differential expression of 7 selected miRNAs was confirmed by real time PCR. Pathway enrichment analysis revealed that the most deregulated miRNAs (miR-1, miR-133, miR-143 and miR-145) collectively targeted a number of genes belonging to signaling pathways such as TGF-β, ErbB3, WNT and VEGF, and those regulating cell motility or adhesion. The ectopic expression of miR-1 and miR-145 in NOZ cells significantly inhibited cell viability and colony formation (P < 0.01) and reduced gene expression of VEGF-A and AXL. This study represents the first investigation of the miRNA expression profile in gallbladder cancer, and our findings showed that several miRNAs are deregulated in this neoplasm. In vitro functional assays suggest that miR-1 and miR-145 act as tumor suppressor microRNAs in GBC.
Available from: Jan L Bjersing
- "miR-145-5p correlated with pain and fatigue in the FM patients. miR-145 inhibits growth and is a potential modulator of the insulin-like growth factor pathway. miR-145 was downregulated in endometriosis patients, in ulcerative colitis patients and in experimental studies of prenatal stress. However, in this small sample of patients with FM, post-hoc analysis did not show any significant correlation between miR-145-5p and serum-free or total insulin-like growth factor 1 (data not shown). "
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ABSTRACT: Fibromyalgia (FM) is characterized by chronic pain and reduced pain threshold. The pathophysiology involves disturbed neuroendocrine function, including impaired function of the growth hormone/insulin-like growth factor-1 axis. Recently, microRNAs have been shown to be important regulatory factors in a number of diseases. The aim of this study was to try to identify cerebrospinal microRNAs with expression specific for FM and to determine their correlation to pain and fatigue.
The genome-wide profile of microRNAs in cerebrospinal fluid was assessed in ten women with FM and eight healthy controls using real-time quantitative PCR. Pain thresholds were examined by algometry. Levels of pain (FIQ pain) were rated on a 0-100 mm scale (fibromyalgia impact questionnaire, FIQ). Levels of fatigue (FIQ fatigue) were rated on a 0-100 mm scale using FIQ and by multidimensional fatigue inventory (MFI-20) general fatigue (MFIGF).
Expression levels of nine microRNAs were significantly lower in patients with FM patients compared to healthy controls. The microRNAs identified were miR-21-5p, miR-145-5p, miR-29a-3p, miR-99b-5p, miR-125b-5p, miR-23a-3p, 23b-3p, miR-195-5p, miR-223-3p. The identified microRNAs with significantly lower expression in FM were assessed with regard to pain and fatigue. miR-145-5p correlated positively with FIQ pain (r=0.709, p=0.022, n=10) and with FIQ fatigue (r=0.687, p=0.028, n=10).
To our knowledge, this is the first study to show a disease-specific pattern of cerebrospinal microRNAs in FM. We have identified nine microRNAs in cerebrospinal fluid that differed between FM patients and healthy controls. One of the identified microRNAs, miR-145 was associated with the cardinal symptoms of FM, pain and fatigue.
Available from: Konstantinos G Stravodimos
- "Inhibition of cell growth, in terms of cell cycle arrest and apoptosis, is promoted by miR-145 through the silencing of MYC (c-Myc; Sachdeva et al, 2009), IRS-1 and -2 (Law et al, 2012), RTKN (Wang et al, 2009), EGFR and NUDT1 (Cho et al, 2011), TNSF10 (Zaman et al, 2010), SWAP70 (Chiyomaru et al, 2011), DFFA (DFF45; Zhang et al, 2010), CBFB, CLINT1 and PPP3CA (Ostenfeld et al, 2010). In addition, miR-145 has been found to protect from cancer cell invasion and metastasis throughout the repression of MUC1 (Sachdeva and Mo, 2010a), FSCN1 (Chiyomaru et al, 2010; Fuse et al, 2011), SERPINE1 (Villadsen et al, 2012) and RPS6KB1 (p70S6K1; Xu et al, 2012). "
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Prostate cancer (PCa) is characterised by great heterogeneity of the disease progression rate. Tumours range from insignificant and not life threatening to high risk for relapse ones. Consequently, a large number of patients undergo unnecessary treatment. miR-145 is a well-documented tumour suppressor and its expression, which is regulated by the p53 pathway, has been found to be decreased in the majority of human malignancies. The aim of our study was to evaluate the clinical utility of miR-145 for the prognostication of PCa.
Total RNA was isolated from 137 prostate tissue specimens obtained from 73 radical prostatectomy-treated PCa patients and 64 transurethral- or open prostatectomy-treated benign prostate hyperplasia (BPH) patients. Following polyadenylation and reverse transcription, miR-145 levels were determined by quantitative real-time PCR assay, using SNORD48 (RNU48) for normalisation purposes.
Downregulated miR-145 expression was found in PCa compared with BPH patients. The reduction of miR-145 expression in PCa was correlated with higher Gleason score, advanced clinical stage, larger tumour diameter and higher prostate-specific antigen (PSA) and follow-up PSA levels. In addition, higher risk for biochemical recurrence and significantly shorter disease-free survival (DFS) was found for the PCa patients expressing lower miR-145. Focusing on ‘low- and intermediate-recurrence risk' PCa patients, miR-145 loss was revealed to be a reliable predictor of biochemical relapse and poor DFS independent from Gleason score, clinical stage, PSA and patients' age.
The loss of the tumour-suppressor miR-145 increases the risk for disease progression and predicts the poor survival of PCa patients.
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