MicroRNA-143 and -145 modulate the phenotype of synovial fibroblasts in rheumatoid arthritis

Fibroblast-like synoviocytes (FLSs) constitute a major cell subset of rheumatoid arthritis (RA) synovia. Dysregulation of microRNAs (miRNAs) has been implicated in activation and proliferation of RA-FLSs. However, the functional association of various miRNAs with their targets that are characteristic of the RA-FLS phenotype has not been globally elucidated. In this study, we performed microarray analyses of miRNAs and mRNAs in RA-FLSs and osteoarthritis FLSs (OA-FLSs), simultaneously, to validate how dysregulated miRNAs may be associated with the RA-FLS phenotype. Global miRNA profiling revealed that miR-143 and miR-145 were differentially upregulated in RA-FLSs compared to OA-FLSs. miR-143 and miR-145 were highly expressed in independent RA-FLSs. The miRNA-target prediction and network model of the predicted targets identified insulin-like growth factor binding protein 5 (IGFBP5) and semaphorin 3A (SEMA3A) as potential target genes downregulated by miR-143 and miR-145, respectively. IGFBP5 level was inversely correlated with miR-143 expression, and its deficiency rendered RA-FLSs more sensitive to TNFα stimulation, promoting IL-6 production and NF-κB activity. Moreover, SEMA3A was a direct target of miR-145, as determined by a luciferase reporter assay, antagonizing VEGF165-induced increases in the survival, migration and invasion of RA-FLSs. Taken together, our data suggest that enhanced expression of miR-143 and miR-145 renders RA-FLSs susceptible to TNFα and VEGF165 stimuli by downregulating IGFBP5 and SEMA3A, respectively, and that these miRNAs could be therapeutic targets.

Pitavastatin Regulates Ang II Induced Proliferation and Migration via IGFBP-5 in VSMC

Angiotensin II (Ang II), a key mediator of hypertensive, causes structural changes in the arteries (vascular remodeling), which involve alterations in cell growth, vascular smooth muscle cell (VSMC) hypertrophy. Ang II promotes fibrotic factor like IGFBP5, which mediates the profibrotic effects of Ang II in the heart and kidneys, lung and so on. The purpose of this study was to identify the signaling pathway of IGFBP5 on cell proliferation and migration of Ang II-stimulated VSMC. We have been interested in Ang II-induced IGFBP5 and were curious to determine whether a Pitavastatin would ameliorate the effects. Herein, we investigated the question of whether Ang II induced the levels of IGFBP5 protein followed by proliferation and migration in VSMC. Pretreatment with the specific Angiotensin receptor type 1 (AT1) inhibitor (Losartan), Angiotensin receptor type 2 (AT2) inhibitor (PD123319), MAPK inhibitor (U0126), ERK1/2 inhibitor (PD98059), P38 inhibitor (SB600125) and PI3K inhibitor (LY294002) resulted in significantly inhibited IGFBP5 production, proliferation, and migration in Ang II-stimulated VSMC. In addition, IGFBP5 knockdown resulted in modulation of Ang II induced proliferation and migration via IGFBP5 induction. In addition, Pitavastatin modulated Ang II induced proliferation and migration in VSMC. Taken together, our results indicated that Ang II induces IGFBP5 through AT1, ERK1/2, P38, and PI3K signaling pathways, which were inhibited by Pitavastatin. These findings may suggest that Pitavastatin has an effect on vascular disease including hypertension.

Insulin Like Growth Factor Binding Protein-5 Regulates Excessive Vascular Smooth Muscle Cell Proliferation in Spontaneously Hypertensive Rats via ERK 1/2 Phosphorylation

Insulin-like growth factor binding proteins (IGFBPs) are important components of insulin growth factor (IGF) signaling pathways. One of the binding proteins, IGFBP-5, enhances the actions of IGF-1, which include the enhanced proliferation of smooth muscle cells. In the present study, we examined the expression and the biological effects of IGFBP-5 in vascular smooth muscle cells (VSMCs) from spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY). The levels of IGFBP-5 mRNA and protein were found to be higher in the VSMC from SHR than in those from WKY. Treatment with recombinant IGFBP-5-stimulated VSMC proliferation in WKY to the levels observed in SHR. In the VSMCs of WKY, incubation with angiotensin (Ang) II or IGF-1 dose dependently increased IGFBP-5 protein levels. Transfection with IGFBP-5 siRNA reduced VSMC proliferation in SHR to the levels exhibited in WKY. In addition, recombinant IGFBP-5 significantly up-regulated ERK1/2 phosphorylation in the VSMCs of WKY as much as those of SHR. Concurrent treatment with the MEK1/2 inhibitors, PD98059 or U0126 completely inhibited recombinant IGFBP-5-induced VSMC proliferation in WKY, while concurrent treatment with the phosphatidylinositol-3 kinase inhibitor, LY294002, had no effect. Furthermore, knockdown with IGFBP-5 siRNA inhibited ERK1/2 phosphorylation in VSMC of SHR. These results suggest that IGFBP-5 plays a role in the regulation of VSMC proliferation via ERK1/2 MAPK signaling in hypertensive rats.

Functional roles and clinical values of insulin-like growth factor-binding protein-5 in different types of cancers / 癌症

Insulin-like growth factor-binding proteins(IGFBPs) are critical regulators of the mitogenic activity of insulin-like growth factors (IGFs). IGFBP5, one of these IGFBPs, has special structural features, including a nuclear transport domain, heparin-binding motif, and IGF/extracellular matrix/acid-labile subunit-binding sites. Furthermore, IGFBP5 has several functional effects on carcinogenesis and even normal cell processes, such as cell growth, death, motility, and tissue remodeling. These biological effects are sometimes related with IGF (IGF-dependent effects) and sometimes not (IGF-independent effects). The functional role of IGFBP5 is most likely determined in a cell-type and tissue-type specific manner but also depends on cell context, especially in terms of the diversity of interacting proteins and the potential for nuclear localization. Clinical findings show that IGFBP5 has the potential to be a useful clinical biomarker for predicting response to therapy and clinical outcome of cancer patients. In this review, we summarize the functional diversity and clinical importance of IGFBP5 in different types of cancers.

Gene Expression Profiles of Uterine Normal Myometrium and Leiomyoma and Their Estrogen Responsiveness In Vitro

BACKGROUND: Uterine leiomyomas are common benign smooth muscle tumors among the reproductive aged-women. The research has been aimed to identify the differentially expressed genes between normal myometrium and leiomyoma and to investigate the effects of E2 on their expression. METHODS: Gene microarray analysis was performed to identify the differentially expressed genes between normal myomerium and leiomyoma. The data was confirmed at protein level by tissue microarray. RESULTS: Gene microarray analysis revealed 792 upregulated genes in leiomyoma. Four genes (tropomyosin 4 [TPM4], collagen, type IV, alpha 2 [COL4alpha2], insulin-like growth factor binding protein 5 [IGFBP5], tripartite motif-containing 28 [TRIM28]) showed the most dramatic upregulation in all leiomyoma samples. Tissue microarray analyses of 262 sample pairs showed significantly elevated expression of TPM4, IGFBP5, estrogen receptor-alpha, and progesterone receptor (PR) protein in leiomyoma from the patients in their forties, COL4alpha2 in the forties and fifties age-groups, and TRIM28 in the thirties age-group. PR, insulin-like growth factor 1 (IGF-1), IGF-1 receptor (IGF-1R) and IGFBP5 were induced by E2 in in vitro culture of tissue explants from which cells migrated throughout the plate. Among these, PR, IGF-1, IGFBP5 genes showed higher expression in tissue compared to cells-derived from tissue in leiomyoma and IGF-1R in leiomyoma cell. CONCLUSIONS: This observation implies the importance of the whole tissue context including the cells-derived from tissue in the research for the understanding of molecular mechanism of leiomyoma. Here, we report higher expression of TRIM28 in leiomyoma for the first time and identify E2-responsive genes that may have important roles in leiomyoma development.

Interstitial tissue-specific gene expression in mouse testis by intra-tunica albuguineal injection of recombinant baculovirus / 亚洲男科学杂志(英文版)

The purpose of this study is to establish a gene delivery system for interstitial tissue-specific protein expression in mice testes using modified recombinant baculovirus. Green fluorescent protein (GFP)-expressing recombinant baculovirus (GFP-baculovirus), in which the insect cell-specific polyhedron promoter was replaced by the cytomegalovirus (CMV)-IE promoter, was used to transfect testicular cells in vitro, and for intra-tunica albuguineal injection of the interstitial tissue of the testis. GFP expression was monitored in frozen testes sections by fluorescence microscopy. Expression of GFP in testicular tissues was also assessed by reverse transcription polymerase chain reaction (RT-PCR), and protein expression was assessed by Western blot. Testicular cells in vitro were infected efficiently by modified recombinant GFP-baculovirus. Intra-tunica albuguineal injection of GFP-baculovirus into the mouse testis resulted in a high level of GFP expression in the interstitial tissues. RT-PCR analysis clearly showed GFP gene expression in the testis, particularly interstitial tissues. Intra-tunica albuguineal injection of a modified baculovirus that encoded recombinant rat insulin-like growth factor binding protein (IGFBP)-5 resulted in an increase in IGFBP-5 in testis and semen. In conclusion, we have developed an efficient delivery system for gene expression in vivo in testicular cells, particularly cells of the interstitial tissue using intra-tunica albuguineal injection of a modified recombinant baculovirus. This method will be particularly relevant for application that requires gene delivery and protein expression in the testicular cells of the outer seminiferous tubule of the testis.

Expression of insulin like growth factor binding protein-5 in drug induced human gingival overgrowth.

BACKGROUND & OBJECTIVE: Insulin like growth factor binding proteins (IGFBPs) control the distribution, function and activity of insulin like growth factors (IGFs) in various cells, tissues and body fluids, thereby modulating their metabolic and mitogenic effects. IGFBP-5, the most conserved IGFBP, can function through IGF or directly play a role in fibrosis. Cyclosporine A (CsA) widely used in organ transplant patients, often causes various side effects including gingival fibrotic overgrowth. This study was carried out to assess the mRNA expression of IGFBP-5 in healthy human gingival, chronic periodontitis and CsA induced gingival overgrowth tissues. METHODS: Total RNA was isolated from gingival tissues collected from eight patients with chronic periodontitis, eight patients with CsA induced gingival outgrowth and an equal number of healthy individuals, and subjected to reverse transcription (RT)-PCR for IGFBP-5 gene expression. RESULTS: CsA induced gingival overgrowth tissues expressed increased IGFBP-5 mRNA compared to control and chronic periodontitis. INTERPRETATION & CONCLUSION: Increased mRNA expression of IGFBP-5 in CsA induced gingival outgrowth tissues may be associated with increased collagen synthesis, thereby promoting fibrogenesis.

Alterations of Insulin-like Growth Factor-I mRNA and IGF Binding Protein-5 mRNA Expression Following Hypoxic-Ischemic Brain Injury in Immature Rat / 대한소아내분비학회지

PURPOSE:Insulin-like growth factor-I(IGF-I) is an essential anabolic factor for postnatal rat brain development and IGF-I expression is highly abundant during the first 21 days, critical growth period. Hypoxic-ischemic brain insults occurring during the perinatal period result in neuronal necrosis and permanent brain damage. To investigate the regulation of the action of IGF-I in response to such a hypoxic insult, we examined the gene expression of IGF-I and IGFBP-5 during the first 72 hr after hypoxic-ischemic injury in immature rat brain. METHODS:Ligation of the right carotid artery of 7-day-old rats was followed by 2 hour exposure to 8% oxygen to produce severe hypoxic brain damage. Using reverse transcriptase-polymerase chain reaction(RT-PCR), the expression of IGF-I mRNA and IGFBP-5 mRNA was determined in both hypoxic and control brains at post 1, 4, 12, 24, 48 hr and 72 hr after hypoxic-ischemic insult. RESULTS:The IGF-I mRNA and IGFBP-5 mRNA expression of hypoxic brain were not different from those of controls at 1 hr of recovery but IGF-I mRNA expression was decreased rapidly at post 4 hr, this decrease more pronounced at 12 hr of recovery. IGF-I mRNA and IGFBP-5 mRNA expression were increased at 48 hr and 24 hr of recovery, respectively and both IGF-I mRNA and IGFBP-5 mRNA expression showed similar level of controls at 72 hr of recovery. CONCLUSION: Out findings suggest that IGF-I play a important role in both neuronal loss and repair process following hypoxic-ischemic brain injury and IGFBP-5 is also strongly involved in the repair of damaged brain tissue by mediating IGF-I action. (J Korean Soc Pediatr Endocrinol 2003;8:56-63)

Factores de crecimiento insulino símiles: estructura, bioactividad y métodos de ensayo / Insulin-like growth factors: structure, bioativity and methods of assay

El sistema de los factores de crecimiento insulino-símiles (IGF) se halla involucrado en diferentes aspectos de la regulación celular y tisular, como así también en el desarrollo y el crecimiento corporal. Este sistema depende de la interacción entre ligandos (IGF-I, IGF-II), receptores (Tipo I, Tipo II), proteínas ligadoras o transportadoras (IGFBP-1 a -6), y proteasas específicas para las IGFBPs. La acción de los IGFs se encuentra regulada por diferentes factores y estímulos, tales como la hormona de crecimiento, que actúan a diversos niveles. El desarrollo de nuevos métodos para analizar los diferentes componentes del sistema de los IGFs ha aportado elementos adicionales para la evaluación, diagnóstico y seguimiento de pacientes con alteraciones del crecimiento

The Effect of Sex Steroid Hormone on the Expression of Insulin-Like Growth Factor Binding Preteins mRNA in the Explant Cultured from Human Uterine Myoma and Adjacent Normal Myometrium / 대한내분비학회지

BACKGROUND: Sex steroid hormones are believed to play an important role in the genesis and growth of uterine myoma. Several studies suggest a possible role of insulin-like growth factor(IGF) as a mediator of estradiol in uterine myama. We have recently demonstrated that some IGF binding proteins(IGFRPs) messenger ribonucleic acid(mRNA) expressions in myoma are dependent on the in vivo esttogen status. The purposes of this study are to evaluate the in vitro effects of sex steroid hormones including estrogen on the IGFBPs gene expression in tissues from uterine myoma and adjacent normal myometrium. METHODS: Tissues from myoma and adjacent normal myometrium of patients with uterine myoma during early proliferative phase of menstrual cycle were cultured in the absence(control) and presence of 17b-estradiol(10M/L) or/and progesterone(10M/L) for 3 days. The IGFBPs mRNA expressions in these explants were analyzed by Nothern blot using specific human complementary deoxyribonucleic acid(cDNA) probes. RESULTS: The addition of 17b-estradiol, progesterone alone and in combination to conditioned media of explants from myoma and adjacent normal myornetrium did not result in any changes in the expression of IGFBP-2, IGFBP-4, IGFBP-5, and IGFBP-6 mRNA. With progesterone addtion, lGFBP-3 rnRNA expression was significantly reduced in myoma explant but not in adjacent ncemal myometrium explant. There was no significant change in the IGFBP-3 mRNA expression with 17b-estradiol and with the combination of both 17b-estradiol and progesterone. CONCLUSION: 17b-estradiol does not affect IGFBPs gene expression in the myoma and adjacent normal myometrium explant regardless of the presence of progesterone in vitro. However progesterone alone induces a decrease in IGFBP-3 synthesis in myoma explant.