MiR-329 suppresses osteosarcoma development by downregulating Rab10

Transcription

1 MiR-329 suppresses osteosarcoma development by downregulating Rab10 Wenwei Jiang 1*, Jin Liu 2*, Tianyang Xu 1 and Xiao Yu 3 1 Department of Orthopedics, Shanghai Tenth People s Hospital, Tong Ji University School of Medicine, China 2 Department of Orthopedics, Wuxi Taihu Hospital, China 3 Department of Orthopedics, Suzhou Municipal Hospital of Nanjing Medical University, China Correspondence X. Yu, Department of Orthopedics, Suzhou Municipal Hospital of Nanjing Medical University, 26 DaoQian Street, Suzhou , China Fax: Tel: @139.com *These authors contributed equally to this work. (Received 30 June 2016, revised 18 July 2016, accepted 24 July 2016, available online 19 August 2016) MiR-329 has been proved to be a tumor suppressor gene in various malignancies, however, its role in osteosarcoma remains elusive. We found that mir- 329 is remarkably downregulated in osteosarcoma tissues and relates to advanced stages. MiR-329 is able to inhibit osteosarcoma cell proliferation, promote apoptosis, and induce G0/G1 cell cycle arrest. In addition, mir-329 also suppresses wound-healing and migration ability of osteosarcoma cells and inhibits tumorigenicity in vivo. Rab10 was identified as a target of mir- 329 in osteosarcoma and mediates its biofunction. These findings may shed light to the understanding of tumor development in osteosarcoma. Keywords: growth; migration; mir-329; osteosarcoma; Rab10 doi: / Edited by Tamas Dalmay Osteosarcoma (OS) is the second most common primary malignant bone tumor and leads to a large number of cancer-related deaths in children and young adults (median age of diagnosis: 18 years) [1]. It represents the third highest cause of cancer-related death in this age group [2]. The development of combination treatment with neoadjuvant chemotherapy and radical surgery has significantly increased the survival rates from 20 to 75% [3,4]. However, even after curative resection of primary tumors, a considerable number of patients still experience distant metastases or local recurrence [5]. The clinical prognosis of these metastatic or recurrent patients is extremely poor. Thus, discovery of new biomarkers and effective therapeutic targets for OS are crucial. MiRNA are a class of small regulatory RNA molecules, that obstruct the translation of mrna by binding to the 3 0 -UTR of the corresponding mrna [6]. Compelling studies have proved that mirna take part in most tumor biological processes such as metastasis, cell proliferation, differentiation, and apoptosis [7,8]. Indeed, aberrant mirna expression has been found in OS, which has been shown to contribute to cancer development and metastasis by inhibiting tumor suppressor genes or promoting oncogene expression [9,10]. For example, mir-144 suppresses OS progression by directly downregulating ROCK1 and ROCK2 expression [11], overexpression of mir-542-5p promotes the proliferation of OS by targeting HUWE1 [12]. Abnormal mir-329 expression in tumor tissues, such as glioma [13], neuroblastoma [14], and gastric cancer [15], suggests that mir-329 is significant in cancer pathogenesis and progression. However, whether mir- 329 plays a role in OS development is still elusive. In this study, we analyzed mir-329 expression in OS tissues and investigated its effects on OS development. Abbreviations NC, negative control; OS, osteosarcoma; qrt-pcr, quantitative real-time PCR; UTR, 3 0 -untranslated regions; WST, water-soluble tetrazolium salt. 2973

2 MiR-329 suppresses osteosarcoma W. Jiang et al. Materials and methods Tissue specimens and cell culture The clinical research protocol was approved by the Ethical Committee of Shanghai Tenth People s Hospital, Tong Ji University School of Medicine. A total of 62 sets of osteosarcoma and adjacent nontumor tissues were obtained from patients who underwent curative surgery at Shanghai Tenth People s Hospital between January 2011 and December None of the patients had received chemotherapy prior to surgery. For the use of clinical materials for research purposes, prior patient consent was obtained. Tissues were harvested freshly after samples dissection, snap-frozen in liquid nitrogen, and finally preserved at 80 C. The normal human osteoblast cell line hfob 1.19, and OS cell lines 143B, HOS, Saos-2, U2OS, and MG-63 were purchased from American Type Culture Collection (Manassas, VA, USA). The five OS cell lines and hfob 1.19 cells were cultured in RPMI 1640 supplemented with 10% FBS, 100 UmL 1 penicillin, and 100 mgml 1 streptomycin at 37 C in a humidified incubator containing 5% CO 2. Quantitative real-time PCR (qpcr) Total RNA was isolated from tissue samples and cell lines using Trizol reagent (Invitrogen, Carlsbad, CA, USA) according to the manufacturer s instructions. cdna was synthesized with 1ug RNA using reverse transcription kit (Toyobo, Osaka, Japan). SYBR Green reagent (Applied Biosystems, Foster City, CA, USA) was used for qrt- PCR to analysis mrna expression. U6 small nuclear RNA was used as an endogenous control for mir-329 normalization. Relative expression ratios of mir-329 in each paired tumor cancer to normal tissue sample were calculated using the 2 DDCt method. MiR-329 and U6 primers were purchased from GenePharma (Shanghai, China). The PCR primers designed for Rab10: 5 0 -CAAGGGAGCATG GTATTAGGTTT-3 0 (forward) and 5 0 -CTAACGTGAGG AACGCCTTTT-3 0 (reverse); for GAPDH: 5 0 -GACCTGA CCTGCCGTCTAG -3 0 (forward) and 5 0 -GTAGCCCAGG ATGCCCTTGA -3 0 (reverse). Transient transfection MiR-329 mimics (dsrna oligonucleotides), negative control (NC), mir-329 inhibitor, and inhibitor negative control were purchased from GenePharma (Shanghai, China). Cells in logarithmic growth phase were trypsinized, counted, and seeded in six-well plates to ensure 50% cell confluence on the next day for transfection. Oligonucleotide transfection was performed using Lipofectamine 2000 Reagent (Invitrogen). Transfection efficiency was calculated by qrt-pcr. Cell proliferation assay At 24 h post transfection with mir-329 mimics/inhibitors or control oligonucleotides, cells were seeded into 96-well plates ( cells/well) and cell proliferation was documented every 24 h for 4 days. Cell proliferation was measured by the colorimetric water-soluble tetrazolium salt (WST) assay with a Cell Counting Kit-8 according to the manufacturer s instructions (Dojindo, Kumamoto, Japan). Absorbance was measured at 450 nm with a MicroplateAutoreader (Bio-Rad, Hercules, CA, USA). All experiments were performed in triplicate. Colony formation assay and soft agar colony formation assay For colony formation assay, cells were seeded into six-well plates with cells/well in 4 ml culture medium which was replaced every 3 4 days and incubated for 10 days. The number of colonies was counted using a phase-contrast microscope at a magnification of 49 after staining with 0.5% crystal violet solution. We counted the colonies which containing at least 50 cells. The experiments were independently triplicated. For soft agar colony formation assay, mirna mimic/inhibitor-transfected MG-63/143B cells were resuspended with 0.3% soft agar (A9045; Sigma Aldrich, St. Louis, MO, USA) in RPMI 1640 containing 10% FBS and layered on 0.6% solidified agar in RPMI 1640 containing 10% FBS in six-well plates ( cells/well) 24 h post transfection. The plates were incubated for 2 weeks. Colonies were photographed using a phase-contrast microscope at a magnification of 109. Apoptosis and cell cycle analysis For cell cycle analysis, cells were transfected with mir-329 mimics or mir-329 inhibitors and their controls, then cells were harvested 48 h post transfection and finally we performed the flow cytometry using the AnnexinV/PI doublestaining kit (BD Biosciences, San Jose, MA, USA) according to the manufacturer s instructions. All assays were repeated at least three times. For cell cycle analysis, cells were first fixed using 70% ethanol and stored at 4 C overnight. After that, the fixed cells were washed with PBS, treated with 2 ll of RNase A (50 lgml 1 ), and stained with 20 ll of Propidium Iodide (50 lgml 1 )at37 C for 30 min in dark. Cell cycle distribution was analyzed using FACSCaliber (BD Bioscience). Wound-healing assay and cell migration assay Cells were seeded in six-well plates and allowed to reach confluence. Wounds were scratched on the monolayer of cells using 20-mL pipette tips. Cells were rinsed with PBS 2974

3 W. Jiang et al. MiR-329 suppresses osteosarcoma and cultured in RPMI 1640 without calf serum. Wound closure was observed at 0 and 48 h, and photographed under a microscope. For cell migration assay, transfected cells ( ) in serum-free medium were added to the top chamber and incubated at 37 C in a humidified incubator containing 5% CO 2 according to the manufacturer s protocols. Medium containing 10% FBS was added to the lower chamber as a chemoattractant. After 24 h of culturing, cells that invaded the lower chamber were stained with 0.5% crystal violet and subsequently counted in five different areas under an inverted microscope. Lentiviral transfection for stable expression cells Lentiviral vectors expressing mir-329 and scrambled RNA were purchased from GenePharma. Lentivirus transfection was performed according to the manufacturer s instruction to establish the stable mir-329-expressing MG-63 cells. The control was constructed similarly without inserted cdna. Tumor xenograft model and tumorigenicity assay All animal studies complied with protocols approved by the Committee on Animal Care in Tong Ji University School of Medicine. LV-miR-NC or LV-miR-329 cells were injected subcutaneously into the flanks of mice ( cells per animal). Tumor size was measured externally every 7 days using a caliper, and tumor volume was estimated using the equation: length (mm) 9 width 2 (mm) Five mice were used for each group. The mice were sacrificed after 4 weeks, and all tumor grafts were harvested and examined histologically. Luciferase reporter assay The 3 0 -UTR of Rab10 was amplified by PCR using cdna from MG-63 cells and cloned into Hind III-MluI sites of the pmir-report mirna expression reporter vector (Applied Biosystems). The mutant Rab UTR was constructed to mutate three intermittent sites complementary to the mir-329 seed-region. The mir-329 mimics or control and luciferase reporter vector were cotransfected into MG-63 cells. Luciferase activity was measured after 48 h using the Dual luciferase reporter assay system (Promega, Madison, WI, USA). Renilla luciferase activity was normalized to that of firefly luciferase. Experiments were repeated at least three times. Western blot Rab10 protein levels were detected according to standard immunoblot protocols, using mouse anti-human Rab10 antibody (1 : 1000; Abcam, Cambridge, MA, USA) and monoclonal anti-gapdh (1 : 5000; Abcam) antibody. Statistical analysis The relationship between mir-329 expression and clinicopathologic features was investigated using Pearson X 2 test. Student t test was used to analyze the difference between two groups and one-way ANOVA for more than two groups. Statistical analysis was performed using SPSS 16.0 software (SPSS Inc., Chicago, IL, USA). P < 0.05 was considered significant, and P < 0.01 was considered highly significant. Results MiR-329 is downregulated in OS patients and correlates with tumor size and Enneking stage In order to investigate the mir-329 expression level in OS, we performed quantitative real-time PCR (qrt- PCR) in tumor tissues and matched nontumor tissues from 62 OS patients. MiR-329 expression was significantly downregulated in tumor tissues compared with the nontumor tissues (Fig. 1A,B). In addition, five OS cell lines also displayed lower levels of mir-329 than the normal human osteoblastic cell line, hfob1.19 (Fig. 1C). Given the remarkable downregulation of mir-329 in OS, we carried on to study the correlation between mir-329 expression and clinicopathologic characteristics of OS patients. All the cases were divided into two groups based on relative expression level: the mir-329 high-expression group (n = 28) and the mir-329 lowexpression group (n = 34). We found that mir-329 low-expression group had inclinations toward larger tumor size (P = 0.011) and more advanced Enneking stage (P = 0.039). However, no relationship was observed between mir-329 expression level and gender, age, tumor grade, histological type, or distant metastasis (Table 1). MiR-329 suppresses OS cell proliferation in vitro In order to explore the function of mir-329 in OS cell lines, MG-63 cells, low mir-329 expressing cells, were transfected with mir-329 mimics or negative control (NC). On the other hand, 143B cells, high mir-329 expressing cells, were transfected with mir-329 inhibitors or NC. Then, we utilized CCK8 analysis and colony formation assay to evaluate the effect of mir-329 expression on cell proliferation. As indicated in Fig. 2A,B,C, mir-329 mimics markedly inhibited cell growth, while mir-329 inhibitors significantly induced cell growth induction (P < 0.01). We also confirmed these observations in soft agar colony formation assays. The size of colonies of MG-63 cells transfected with mir-329 mimics was smaller than that of controls 2975

4 MiR-329 suppresses osteosarcoma W. Jiang et al. Fig. 1. mir-329 is significantly downregulated in tissues and cell lines. (A) mir-329 expression level in surgical samplesfrom 62 OS tissues and adjacent nontumorous tissues. Data are shown using 2 DCT values. U6 snrna was used for normalization. (B) Relative expression of mir-329 in 62 OS surgical specimens. Results are shown as DDCT values. (C) mir-329 expression level in five OS cell lines compared with hfob1.19. **P < Table 1. Association between mir-329 expression and clinicopathologic factors of osteosarcoma patients. Variables Number of cases mir-329 immunostaining High (n = 28) Low (n = 34) Gender Male Female Age (years) < Tumor grade Low High Anatomic location Tibia/femur Elsewhere Tumor size 8 cm >8 cm Enneking stage I II III Histological type Osteoblastic Fibroblastic Chondroblastic Telangiectatic Others Distant metastasis Absent Present P (P < 0.01, Fig. 2D,E) and 143B cells transfected with inhibitors showed opposite results (P < 0.01, Fig. 2D,E). MiR-329 promotes apoptosis of OS cells and induces G0/G1 cell cycle arrest Flow cytometry analysis was performed to clarify the mechanism of mir-329-mediated cell growth inhibition. MiR-329 mimics increased the apoptotic rate comparing to the control group (P < 0.01, Fig. 3A,B) and mir-329 inhibitor decreased it (P < 0.01, Fig. 3A, B). Moreover, flow cytometry analysis revealed that mir-329 overexpression leads to an increased percentage of cells in the G0/G1 phase (P < 0.05, Fig. 3C,D), alone with a decrease in G2/M-phase cells (P < 0.01, Fig. 3C,D). We also observed the opposite results in mir-329 inhibitor-transfected 143B cells when compared with the negative control cells (P < 0.05, Fig. 3C,D), which suggesting that this mirna induces G0/G1 arrest. MiR-329 inhibits wound-healing and migration ability of OS cells To investigate the effect of mir-329 on motility, we performed wound-healing assays. We observed that mir-329 re-expression suppressed the wound-healing ability of MG-63 cells to a significant extent after 48 h (P < 0.01, Fig. 4A,B). Conversely, the distance 2976

5 W. Jiang et al. MiR-329 suppresses osteosarcoma Fig. 2. mir-329 suppresses OS cell proliferation in vitro. (A) MG-63 cells were transfected with mir-329 mimics or NC mimics, 143B cells were transfected with mir-329 inhibitor or NC control, and cell viability determined with the CCK-8 assay. (B C) Representative photographs (B) and quantitative analysis (C) of plate colony formation of OS cells transfected with mir-329 mimics or mir-329 inhibitors. (D E) Representative photographs (D) and dimension analysis (E) of soft agar colony formation of OS cells transfected with mir-329 mimics or mir-329 inhibitors. **P < between wound edges of 143B cells was markedly shorter when endogenous mir-329 was silenced with specific inhibitors (P < 0.01, Fig. 4C,D). To investigate the influence of mir-329 on migration, we next performed transwell migration assays. Similarly, the migration assays showed that upregulation of mir-329 led to significantly decreased migration ability of MG-63 cells, whereas silencing of mir- 329 induced a marked increase in 143B cell migration (P < 0.01, Fig. 4E,F). MiR-329 inhibits tumorigenicity in vivo We have demonstrated that mir-329 suppresses proliferation in vitro, therefore we continued to investigate if mir-329 has any impact upon tumorigenicity in vivo. Lentivirus-mediated MG-63/miR-329 and MG- 63/miR-NC stably transfected cell lines were obtained and injected into 4-week-old male nude mice subcutaneously, and tumor growth was assessed for 4 weeks. Tumors grew slower (Fig. 5A) and were significantly 2977

6 MiR-329 suppresses osteosarcoma W. Jiang et al. Fig. 3. mir-329 induces cell apoptosis and G0/G1 cell cycle arrest. (A, B) The percentage of apoptotic cells transfected with mir-329 mimics or inhibitors or their controls. (C, D) The percentage of G0/G1, S, G2/M cells transfected with mir-329 mimics or inhibitors or their controls. *P < 0.05, **P < smaller (P < 0.01, Fig. 5B,C) in the MG-63/LV-miR- 329 group than those in the MG-63/LV-miR-NC group. We also found that Ki-67 staining was lower in MG-63/LV-miR-329 tumor samples compared with that in MG-63/LV-miR-NC tumor samples (P < 0.01, Fig. 5D,E). The above mentioned results demonstrated that mir-329 inhibits tumorigenicity in vivo. Rab10 is the target of mir-329 in OS In order to get a better understanding of the mechanism of mir-329 in OS, we went on to identify its downstream target. Rab10 stood out as a promising candidate after software prediction. We found mir- 329 was able to degrade Rab10 mrna and lead to a decreased Rab10 protein level (Fig. 6A,B), which strengthened our hypothesis. Furthermore, we showed that mir-329 mimics decreased the activity of the luciferase reporter harboring wild-type Rab UTR, but not that with mutant Rab UTR (Fig. 6C,D). On the contrary anti-mir-329 increased the luciferase activity of wild-type Luc-Rab10, but had no effect on the mutant (Fig. 6C,E). Next, we examined biofunction of Rab10 in OS, and discovered that knocking down Rab10 inhibited cell growth and migration (Fig. 7), which was very similar with the effect of overexpressing mir-329. The aforementioned data prove that Rab10 is the target of mir-329 and mediates its biofunction in OS. Discussion mir-329 is located on 14q32.31 and is reported to be downregulated in several types of tumor [16,17], however, its expression level in OS is still unknown. In the present study, we, for the first time, show 2978

7 W. Jiang et al. MiR-329 suppresses osteosarcoma Fig. 4. mir-329 suppresses OS cell wound healing and migration in vitro. (A) A representative image of wound-healing assay for MG-63 cells transfected with mir-329 mimics or NC mimics. (B) The distances between wound edges of MG- 63 cells transfected with mir-329 mimics or NC mimics at 0 and 48 h. (C) A representative image of wound-healing assay for 143B cells transfected with mir- 329 inhibitor or NC control. (D) The distances between wound edges of 143 cells transfected with mir-329 inhibitor or NC control at 0 and 48 h. (E) Transwell assay. Photographs show cells that traveled through the micropore membrane. (F) Histograms showed the numbers of migration cells. **P < Fig. 5. mir-329 inhibitstumorigenicity and proliferation in vivo. (A) Photograph of tumors harvested from LV-miR-NC and LVmiR-329 cells in nude mice. (B) Growth kinetics of tumors in nude mice. Tumor diameters were measured every 7 days. (C) The average weight of tumors in nude mice. (D) Photographs of immunohistochemisty analysis of Ki-67 in tumor samples from nude mice (2009). (E) Representative proliferative index of tumors in LV-miR-329 and LV-miR-NC nude mice. *p < 0.05, **p < that mir-329 is significantly downregulated in OS tissues and its low expression relates to large tumor size and advanced Enneking stage. To elucidate the mechanism of such abnormal expression, we discover that mir-329 suppresses OS cell proliferation and migration by targeting Rab10, which may shed light to the understanding of tumor development in OS. 2979

8 MiR-329 suppresses osteosarcoma W. Jiang et al. Fig. 6. Rab10 is the target of mir-329. (A, B) Rab10 mrna and protein level after transfected with mir-329 mimics or inhibitor. (C) Scheme of the mir-329- binding sites in Rab UTR. Rab10-mut represents the Rab UTR with mutational mir-329 binding sites. (D, E) Luciferase reporter activity after transfected with mir-329 mimics or inhibitor in wild-type Rab UTR or mutant Rab UTR reporter. **p < Fig. 7. Knocking down Rab10 inhibits OS cell proliferation and migration. (A) Rab10 was knocked down in OS cells and cell viability was determined by CCK-8 assay. (B) A representative image of migration assay for OS cells transfected with Rab10 shrna or controls. (C) Quantitative analysis of migration OS cells transfected with Rab10 shrna or controls. **p < Relevant studies demonstrate that mir-329, as an oncogene, suppresses tumor development mainly by inhibiting tumor cell proliferation and migration [14 16]. In consistent to these reports, we found that mir- 329 inhibits OS cell proliferation, promotes apoptosis and induces G0/G1 cell cycle arrest. In addition, mir- 329 is also able to suppress wound-healing and migration ability of OS cells and inhibit tumorigenicity in vivo. These finding may justify its low expression and clinical association we discovered. In order to further elucidate the mechanism, we carried on to identify the putative target of mir-329 in OS. Using predicting software, we found a promising target, Rab10 (RAB10, member RAS oncogene family). Rab10 belongs to the RAS superfamily of small GTPases. Given the remarkable role of RAS superfamily plays in tumor development, we hypothesized that Rab10 might be a plausible target of mir-329 and mediate its biological function. Our further experiment corroborates that Rab10 is a direct target of 2980

9 W. Jiang et al. MiR-329 suppresses osteosarcoma mir-329 and its degradation leads to tumor progression in OS. In summary, we demonstrate that mir-329 is downregulated in OS and relates to advanced stage; also, mir-329 suppresses tumor cell proliferation and migration by targeting Rab10. Further studies are required to clarify the effect of other mir-329 targets in OS and if any synergic relationship exists. However, taking into consideration of the significant effect of mir-329, mir-329 itself and its target are potential biomarkers for novel OS management. Author contributions WJ and XY conceived and designed the experiments; WJ and JL performed the experiments; JL and TX analyzed the data; WJ and XY wrote the paper. References 1 Ottaviani G and Jaffe N (2009) The epidemiology of osteosarcoma. Cancer Treat Res 152, Dass CR, Ek ET, Contreras KG and Choong PF (2006) A novel orthotopic murine model provides insights into cellular and molecular characteristics contributing to human osteosarcoma. Clin Exp Metastasis 23, Bacci G, Ferrari S, Bertoni F, Ruggieri P, Picci P, Longhi A, Casadei R, Fabbri N, Forni C, Versari M et al. (2000) Long-term outcome for patients with nonmetastatic osteosarcoma of the extremity treated at the istituto ortopedico rizzoli according to the istituto ortopedico rizzoli/osteosarcoma-2 protocol: an 16 updated report. J Clin Oncol 18, Rytting M, Pearson P, Raymond AK, Ayala A, Murray J, Yasko AW, Johnson M and Jaffe N (2000) Osteosarcoma in preadolescent patients. Clin Orthop Relat Res 373, Sakamoto A and Iwamoto Y (2008) Current status and perspectives regarding the treatment of osteo-sarcoma: chemotherapy. Rev Recent Clin Trials 3, Mei Q, Li X, Guo M, Fu X and Han W (2014) The mirna network: micro-regulator of cell signaling in cancer. Expert Rev Anticancer Ther 14, Calin GA and Croce CM (2006) MicroRNA signatures in human cancers. Nat Rev Cancer 6, Lu J, Getz G, Miska EA, Alvarez-Saavedra E, Lamb J, Peck D, Sweet-Cordero A, Ebert BL, Mak RH, Ferrando AA et al. (2005) MicroRNA expression profiles classify human cancers. Nature 435, Jones KB, Salah Z, Del Mare S, Galasso M, Gaudio E, Nuovo GJ, Lovat F, LeBlanc K, Palatini J, Randall RL et al. (2012) mirna signatures associate with pathogenesis and progression of osteosarcoma. Cancer Res 72, Gougelet A, Pissaloux D, Besse A, Perez J, Duc A, Dutour A, Blay JY and Alberti L (2011) Micro-RNA profiles in osteosarcoma as a predictive tool for ifosfamide response. Int J Cancer 129, Wang W, Zhou X and Wei M (2015) MicroRNA-144 suppresses osteosarcoma growth and metastasis by targeting ROCK1 and ROCK2. Oncotarget 6, Cheng DD, Yu T, Hu T, Yao M, Fan CY and Yang QC (2015) MiR-542-5p is a negative prognostic factor and promotes osteosarcoma tumorigenesis by targeting HUWE1. Oncotarget 6, Xiao B, Tan L, He B, Liu Z and Xu R (2013) MiRNA- 329 targeting E2F1 inhibits cell proliferation in glioma cells. J Transl Med 11, Yang H, Li Q, Zhao W, Yuan D, Zhao H and Zhou Y (2014) mir-329 suppresses the growth and motility of neuroblastoma by targeting KDM1A. FEBS Lett 588, Li Z, Yu X, Wang Y, Shen J, Wu WK, Liang J and Feng F (2015) By downregulating TIAM1 expression, microrna-329 suppresses gastric cancer invasion and growth. Oncotarget 6, Zhou J, Li W, Guo J, Li G, Chen F and Zhou J (2016) Downregulation of mir-329 promotes cell invasion by regulating BRD4 and predicts poor prognosis in hepatocellular carcinoma. Tumour Biol 37, Liu DZ, Ander BP, Tian Y, Stamova B, Jickling GC, Davis RR and Sharp FR (2012) Integrated analysis of mrna and microrna expression in mature neurons, neural progenitor cells and neuroblastoma cells. Gene 495,