microRNA-137 modulates pancreatic cancer cells tumor growth,invasion and sensitivity to chemotherapy

Background: We intended to investigate the role of microRNA 137 (miR-137) in regulating pancreatic cancer cells’ growth in vitro and tumor development in vivo. Methods: QTR-PCR was used to examine the expression of miR-137 in pancreatic cancer cell lines and tumor cells from human patients. Lentivirual vector containing miR-137 mimic was used to overexpress miR-137 in PANC-1 and MIA PaCa-2 cells. The effects of overexpressing miR-137 on pancreatic cancer cell invasion and chemo-sensitivity to 5-fluorouracil (5-FU) were examined by cell migration and survival essays in vitro. The molecular target of miR-137, pleiotropic growth factor (PTN), was down-regulated by siRNA to examine its effects on cancer cell invasion. MIA PaCa-2 cells with endogenously overexpressed miR-137 were transplanted into null mice to examine tumor growth in vivo. Results: We found miR-137 was markedly underexpressed in both pancreatic cancer cell lines and tumor cells from patients. In cancer cells, transfection of lentivirus containing miR-137 mimic was able to markedly upregulate endogenous expression of miR-137, inhibited cancer cell invasion and increased sensitivities to chemotherapy reagent 5-FU. PTN was significantly down-regulated by overexpressing miR-137 in pancreatic cancer cells, and knocking down PTN was effective to rescue the reduced cancer cell invasion ability caused by miR-137 overexpression. More importantly, overexpressing miR-137 led to significant inhibition on tumor formation, including reductions in tumor weight and tumor size in vivo. Conclusion: Our study demonstrated that miR-137 played an important role in pancreatic cancer development. It may become a new therapeutic target for gene therapy in patients suffered from pancreatic cancer.     

MiRNA profile of osteosarcoma with CD117 and stro-1 expression: miR-1247 functions as an onco-miRNA by targeting MAP3K9

microRNAs (miRNA) are regulators of gene expression, but little is known about miRNA expression profiles in stem cells of osteosarcoma (OS). C117 and Stro-1 are known stem cell markers of OS. In the study, CD117 and stro-1 positive (CD117⁺stro-1⁺) and CD117 and stro-1 negative (CD117^-stro-1^-) cells were isolated from MG63 cells CD117⁺stro-1⁺ cells showed more metastatic ability and stem cell formation rate than CD117^-stro-1^- ones. To find the difference between CD117⁺stro-1⁺ and CD117^-stro-1^- cells, the miRNA expression profile was examined using DNA microarray. MicroRNAs were differentially expressed in osteosarcoma cells with CD117⁺stro-1⁺ and CD117^-stro-1^-. The significant miRNAs included miR-15a, miR-302a, miR-423-5p, miR-1247, miR-1243 and others, which were confirmed by real time RT-PCR. The significant down-regulated miR-1247 was confirmed that was a potential tumor suppressor by targeting MAP3K9. Our results indicated that dysregulation of miRNAs is involved in osteosarcoma and miR-1247 plays an important role in progression of osteosarcoma.     

miR-200b调控PDCD4的表达对乳腺癌细胞增殖和侵袭的影响

目的探讨miR-200b对乳腺癌细胞增殖及侵袭的影响及其可能的分子机制。方法利用荧光实时定量PCR检测人乳腺癌组织及乳腺癌细胞株中miR-200b的表达差异;利用生物信息学方法预测miR-200b的靶基因,并使用免疫蛋白印迹实验对靶基因的表达进行验证;分别将miR-200b siRNA、PDCD4 mimics以及相应对照miRNA转染MCF-7细胞,通过CCK-8实验检测细胞的增殖能力;采用Transwell侵袭实验检测细胞的侵袭能力。结果miR-200b在乳腺癌组织中呈低表达水平,进一步抑制miR-200b的表达,乳腺癌细胞的增殖及侵袭能力显著增强(P<0.05);将miR-200b siRNA、PDCD43′-UTR共转染到乳腺癌MCF-7细胞中,双荧光素酶报告基因结果显示抑制miR-200b的表达后,PDCD4的表达及活性相应上调(P<0.05);同时通过蛋白免疫印迹实验可以发现,抑制miR-200b表达后,PDCD4蛋白表达含量降低,乳腺癌细胞的增殖及侵袭能力明显增强(P<0.05);而过表达PDCD4后PDCD4蛋白表达含量增加(P<0.05),乳腺癌细胞的增殖及侵袭能力明显降低(P<0.05)。结论miR-200b可靶向上调PDCD4基因的表达,从而抑制乳腺癌细胞的增殖及侵袭能力。     

反义miR-196a对人胰腺癌PANC-1细胞侵袭和迁移的抑制作用

目的:探讨微小RNA-196a(miR-196a)在胰腺癌细胞系中表达状况及反义miR-196a对人胰腺癌PANC-1细胞生物学行为的影响。方法:miR-196a采用实时荧光定量PCR检测。人工化学合成反义miR-196a并转染PANC-1细胞。CCK-8法检测细胞增殖。流式细胞术检测细胞凋亡情况。通过划痕损伤实验和Transwell小室细胞侵袭、迁移实验检测PANC-1细胞侵袭和迁移能力。构建野生型及突变型核因子κB抑制蛋白α(NFKBIA)3'UTR的萤光素酶报告载体,检测海肾萤光素酶的相对活性以验证miR-196a对NFKBIAmRNA的作用靶点。结果:人胰腺癌细胞系中miR-196a呈高表达;转染反义miR-196a后,PANC-1细胞miR-196a表达下降,其细胞增殖和凋亡无显著改变(P>0.05);而转染反义miR-196a组中通过Transwell小室的细胞数明显低于各对照组(P<0.01)。与各对照组相比,共转染野生型NFKBIA的3'UTR和反义miR-196a可使海肾萤光素酶相对活性显著提高。结论:miR-196a可能是癌微RNA(oncomiR)之一,有望成为人胰腺癌基因治疗的候选靶点。     

miR-133b 靶向 PTBP1 对肾细胞癌增殖和侵袭的影响

目的 探讨 miR-133b 靶向多聚嘧啶区结合蛋白1 (polyrimidine tract binding protein 1, PTBP1) 对 肾细胞癌 (renal cell carcinoma, RCC) 增殖和侵袭的影响。 方法 检测 miR-133b 在 RCC 癌组织及细胞中 的表达水平; 验证 miR-133b 与 PTBP1 的靶向关系及 miR-133b 表达对肾癌细胞 PTBP1 表达及增殖、 迁移的 影响。 结果 与癌旁组织比较, miR-133b 在 RCC 组织中表达下降, 而 PTBP1 上升 (P< 0. 05)。 PTBP1 是 miR-133b 的靶基因; 与 miR-NC 组比较, miR-133b mimic 组的克隆形成率、 侵袭细胞数目及 PTBP1 表达明 显下降, 而 miR-133b inhibitor 组上升; 与 miR-133b mimic + pc-NC 组比较, miR-133b mimic + pc-PTBP1 组的 克隆形成率、 侵袭细胞数目及 PTBP1 表达水平上升 (P< 0. 05)。 结论 miR-133b 在 RCC 癌组织及细胞中 表达下调, 且其可能通过调控 PTBP1 的表达水平来影响细胞的增殖和侵袭能力。     

LncRNA OGFRP1 promotes angiogenesis and epithelial-mesenchymal transition in colorectal cancer cells through miR-423-5p/CTCF axis

ObjectiveTo investigate the mechanism of lncRNA OGFRP1 affecting angiogenesis and epithelial-mesenchymal transition (EMT) in colorectal cancer (CRC) and provide a new target for the treatment of CRC.MethodsThe expressions of OGFRP1, miR-423-5p, and CTCF were measured in CRC cell lines (HT29, LoVo, HCT116, SW620, and SW480) and normal colonic epithelial cells NCM460. Gain and loss of function experiments were performed on HCT116 and SW620 cells, after which the proliferation, apoptosis, EMT, invasion, and migration of the cells were measured using CCK-8 and colony formation assays, flow cytometry, Western blotting, Transwell, and scratch assay. The transfected cells were incubated with human umbilical vein endothelial cells (HUVECs) to assess angiogenesis using tube formation assay. ELISA was performed to detect VEGF in the conditioned medium of HCT116 and SW620 cells. The interactions among OGFRP1, CTCF and miR-423-5p were validated by dual-luciferase reporter assay.ResultsCRC cell lines had increased expression levels of OGFRP1 and CTCF and a suppressed expression level of miR-423-5p when compared with NCM460 cells. Suppression on OGFRP1 or CTCF and overexpression of miR-423-5p led to inhibited proliferation, EMT, invasion and migration and increased apoptosis of HCT116 and SW620 cells. HUVECs incubated with cells transfected with si-OGFRP1, si-CTCF or miR-423-5p mimic had suppressed angiogenesis ability. The effect of OGFRP1 suppression in CRC cells could be counteracted by miR-423-5p inhibition. Both CTCF and OGFRP1 could bind to miR-423-5p.ConclusionOGFRP1 promotes proliferation, EMT, and angiogenesis in CRC through miR-423-5p/CTCF axis.     

Generation of precursor,immature, and mature murine B1‐cell lines from c‐myc/bcl‐xL‐overexpressing pre‐BI cells

Deregulated expression of c‐myc and bcl‐xL is long known to generate transformed B cells in humans and mice. We overexpressed these genes to induce in vitro and in vivo differentiation of fetal liver‐derived mouse pre‐BI cells to B1‐lineage pre‐BII‐like, immature and mature B‐cell lines, and to Ig‐secreting cells. In vitro, doxycycline‐controlled c‐myc/bcl‐xL‐overexpressing CD19⁺CD93⁺c‐kikt⁺IgM^? pre‐BI cells differentiate to and survive as CD19⁺CD93⁺c‐kit^?IgM⁺ immature B1 cells. Timed CpG stimulation of these oncogene‐overexpressing pre‐B or immature B1 cells generates either CD19⁺CD93^lowc‐kit^?IgM^?SLC^? pre‐BII‐like or IgM⁺MHCII⁺CD73⁺CD80⁺CD40⁺ mature B1‐cell lines and IgM‐secreting B1 cells in vitro and fixes their state of differentiation. All cell lines are clonable, but a majority of immature and mature B1‐cell clones eventually reach a nonproliferating, surviving G₀‐state. Transplanted in vivo, c‐myc/bcl‐xL‐overexpressing pre‐B cells expand to mature B1 cells, and to IgM‐ and IgA‐secreting plasmablasts and plasma cells. Within 2 months, plasmablasts have expanded most prominently in BM and spleen, indicating that the host selectively expanded development of these transformed plasma cells. The sIgM⁺ B1‐cell lines and clones offer the possibility to study their roles in the development of B1‐Ab repertoires, of B1‐cell‐mediated autoimmune diseases and of B1‐cell malignancies.     

miR-218 inhibits gastric tumorigenesis through regulating Bmi-1/Akt signaling pathway

Background

Previous studies indicated that miR-218 was deregulated in gastric cancer patients and correlated with tumor invasion and prognosis. The aim of this study was to clarify the effect of miR-218 on the malignant behavior of gastric cancer and its role in regulating Bmi-1/Akt signaling pathway.

Ovarian cancer cells with the CD117 phenotype are highly tumorigenic and are related to chemotherapy outcome

Cancer stem cells (CSCs) play an important role in the recurrence and drug resistance of cancer. Isolation and characterization of CSCs from ovarian cancer samples may help to provide novel diagnostic and therapeutic targets in the management of recurrent disease and drug resistance in ovarian cancer. Here, we developed a xenograft model in which cells from 14 samples of human ovarian serous adenocarcinoma tissue or ascites were implanted in immunodeficient mice to test the tumorigenic potential of different populations of ovarian cancer cells. We identified and isolated the tumorigenic cells as CD117⁺Lineage⁻ from three different xenografts. As few as 10³ cells with the CD117⁺Lineage⁻ phenotype, which comprise < 2% of the xenograft tumor cells, were able to regenerate tumors in a mouse model, a 100-fold increase in tumorigenic potential compared to CD117⁻Lineage⁻ cells. The tumors that arose from purified CD117⁺Lineage⁻ cells reproduced the original tumor heterogeneity and could be serially generated, demonstrating the ability to self-renew and to differentiate, two defining properties of stem cells. Furthermore, immunohistochemistry analysis of 25 patients with advanced ovarian serous adenocarcinoma revealed positive immunostaining for CD117 in 40% (10 of 25) of patients. CD117 expression was statistically correlated with resistance to conventional chemotherapy (P = 0.027). In conclusion, our study demonstrates that human ovarian cancer cells with the CD117⁺ phenotype possess the unique properties of CSCs, including self-renewal, differentiation, a high tumorigenic potential, and chemoresistance. Future studies designed to target CD117⁺ cancer cells may identify more attractive and effective therapies for treatment of ovarian cancer.     

Expression of Tim-3 in gastric cancer tissue and its relationship with prognosis

As a negative regulatory molecule, T-cell immunoglobulin–and mucin domain-3 (Tim-3) plays a crucial role in the tumor immunological tolerance. In the present study, we aimed to determine the Tim-3 expression in gastric cancer tissue and its relationship with clinicopathological parameters and prognosis. The Tim-3 expression was assessed in 52 gastric cancer specimens and 15 gastritis tissues by flow cytometry, and gastritis tissues served as the control. As a result, we found that the Tim-3 expressions on CD4⁺T cells and CD8⁺T cells in gastric cancer tissue was significantly higher than those in gastritis tissue (P=0.022, P=0.047, respectively). The median expression level of Tim-3 on CD4⁺T cells were significantly correlated with clinicopathological parameters, such as tumor size, lymph node metastasis, the depth of tumor invasion and TNM staging (P=0.042, P=0.026, P=0.001, P=0.003, respectively), while it was not correlated with sex, age and histological subtype (all P>0.05). In CD8⁺T cells, the Tim-3 expression was relevant to tumor invasion and TNM staging (P=0.035, P=0.017, respectively), while it was irrelevant to other clinicopathological parameters (all P>0.05). Additionally, Kaplan-Meier survival curves showed that the median overall survival time of patients with lower Tim-3 expression was greater than that of patients with higher Tim-3 expression in CD4⁺T cells and CD8⁺T cells (χ²=18.036, P<0.001 and χ²=18.036, P<0.001, respectively). Moreover, the multivariate analysis revealed that the Tim-3 expression and TNM stage were independent prognostic factors for gastric cancer patients (P=0.029, P=0.043 and P=0.003, respectively). These results suggest that Tim-3 played an important role in the development and progression of gastric cancer, and it could be used as an independent prognostic factor for gastric cancer patients.     

Mechanism underlying the regulation of lncRNA ACTA2-AS1 on CXCL2 by absorbing miRNA-532-5p as ceRNA in the development of ovarian cancer

Objective: To explore the mechanism underlying the regulation of long non-coding RNA (LncRNA) ACTA2-AS1 on CXCL2 as a ceRNA of miR-532-5p in the progression of ovarian cancer (OC). Methods: A qRT-PCR assay was carried out for analyzing the expression changes of ACTA2-AS1, miR-532-5p, as well as CXCL2 in OC tissues and corresponding healthy paracancerous tissues HOSEpiC (human ovarian epithelial cells), and OC cells. OC cells were grouped and transfected, and the fluorescent in situ hybridization was adopted for evaluating ACTA2-AS1 in the cells. Additionally, a dual luciferase reporter (DLR) assay was carried out for verifying the correlation of ACTA2-AS1 with miR-532-5p and of miR-532-5p with CXCL2. Cells were transfected with si-ACTA2-AS1, miR-532-5p, or CXCL2 overexpression plasmids, and then the cell proliferation, invasion, and apoptosis were determined using MTT, Transwell, and flow cytometry assays, respectively. Results: Compared with paracancerous tissues and HOSEpiC cells, OC tissues and cells showed increased ACTA2-AS1 and CXCL2 expression and decreased miR-532-5p expression (all P<0.05). ACTA2-AS1 acted as ceRNA in OC by negatively regulating miR-532-5p. Additionally, upregulating ACTA2-AS1 intensified the proliferation and invasion of cancer cells and suppressed their apoptosis (all P<0.05), and inhibition of it resulted in opposite results. In contrast, overexpressing miR-532-5p suppressed the proliferation, invasion, and clone formation of the cells and promoted their apoptosis (all P<0.05). The effect of ACTA2-AS1 on OC cells can be partially reversed by overexpressing miR-532-5p. Moreover, CXCL2, positively correlated with ACTA2-AS1 in expression (P<0.0001, r=0.7385), was the target of miR-532-5p, and its overexpression could partially offset the influence of miR-532-5p on OC cells. Conclusion: LncRNA ACTA2-AS1 can act as a tumor promoter in OC by absorbing miR-532-5p as ceRNA and regulating CXCL2, and ACTA2-AS1 inhibitor is expected to play a role in targeted therapy of OC.     

MiR-520b inhibits proliferation,migration and invasion in gallbladder carcinoma by targeting RAB22A

IntroductionPrevious studies have reported that miR-520b exhibited inhibitory effects on various human tumors, whereas the effects of miR-520b on gallbladder carcinoma (GBC) have remained unclear. To investigate the effects of miR-520b on GBC progression and reveal the underlying mechanisms, this study was performed.Material and methodsMiR-520b and RAB22A mRNA levels were analyzed by quantitative real-time PCR (qPCR). RAB22A protein level was analyzed via Western blot and immunohistochemical (IHC) analysis. The proliferation, colony formation ability, migration and invasion of NOZ cells were measured via MTT, colony formation, wound healing and transwell invasion assay respectively.ResultsMiR-520b expression level was lower in human GBC tissues than that in neighboring normal tissues. MiR-520b mimic repressed NOZ cell proliferation, colony formation ability, migration and invasion, whereas miR-520b inhibitor exhibited opposite effects. Dual luciferase reporter assay confirmed that miR-520b could bind to the 3′-untranslated regions of RAB22A mRNA. Moreover, RAB22A overexpression significantly abolished the anti-tumor effects of miR-520b in a NOZ cell model. Western blot, qPCR and IHC analysis proved that human GBC tissues showed a higher RAB22A expression level than neighboring normal tissues. Additionally, there was a negative association between miR-520b and RAB22A expression.ConclusionsMiR-520b had suppressive effects on GBC via targeting RAB22A in vitro.     

miR-30c抑制宫颈癌细胞恶性表型的分子机制研究

目的:探讨微小RNA(miR)-30c过表达抑制宫颈癌细胞恶性表型的分子机制。方法:运用Lipofectamine 2000转染法将pGenesil-1-miR-30 c质粒转染宫颈癌细胞系C33A、HeLa、SiHa和CaSki,以转染p-Geresil-1的细胞为阴性对照;运用TaqMan real-time PCR检测各组细胞中miR-30c的表达水平;采用MTT法、集落形成实验、Transwell法、Annexin V-FITC及流式细胞术分别测定细胞活力抑制率、集落形成能力、迁移率及凋亡率;Western blot检测Bax、Bcl-2、基质金属蛋白酶(MMP)-9、MMP-13和金属蛋白酶组织抑制物1(TIMP-1)的蛋白表达水平。结果:转染p Genesil-1-miR-30c质粒的宫颈癌细胞系中miR-30c表达水平均显著高于阴性对照组(P0.01);过表达miR-30 c的宫颈癌细胞活力抑制率显著高于阴性对照组(P0.05),细胞集落形成率和迁移率显著低于阴性对照组(P0.05);流式细胞术检测结果显示,miR-30c过表达的宫颈癌细胞凋亡率显著高于对照组(P0.05);Western blot结果显示miR-30 c过表达促进Bax和TIMP-1蛋白的表达,而抑制Bcl-2和MMP-13蛋白的表达(P0.05或P0.01)。结论 :miR-30 c过表达抑制宫颈癌细胞活力和迁移,诱导宫颈癌细胞凋亡,其机制与激活细胞凋亡通路及抑制MMP-13表达有关。     

Circulating CD137+CD8+ T cells accumulate along with increased functional regulatory T cells and thoracic tumour burden in lung cancer patients

CD137 is a promising target for immunostimulation strategies against cancer. Previous studies showed that CD137⁺CD8⁺ T cells are enriched in antitumour effector T cells in both preclinical tumour models and cancer patients, but to date, such T cells in the blood of lung cancer patients have not been sufficiently investigated. In this study, circulating antigen‐activated CD8⁺ T cell subsets, identified as CD137⁺CD8⁺ or PD‐1⁺ (programmed cell death protein 1) CD8⁺, and regulatory T cells (Treg), identified as CD4⁺CD25⁺CD127^low/?, in 40 untreated lung cancer patients and in 49 age‐ and sex‐matched healthy controls (HCs) were assessed by flow cytometry. Results were evaluated for associations with lung cancer patient clinical characteristics. Correlations between antigen‐activated CD8⁺ T cells and effector Treg (CTLA‐4⁺ [cytotoxic T‐lymphocyte antigen 4] CD4⁺CD25⁺CD127^low/?) were also investigated. Higher percentages of PD‐1⁺, CD137⁺ and PD‐1⁺CD137⁺ amongst CD8⁺ T cells were observed in lung cancer patients compared with HCs. The percentages of CD137⁺CD8⁺ and PD‐1⁺CD137⁺CD8⁺ T cell subsets amongst CD8⁺ T cells were positively correlated with thoracic tumour burden and were strongly positively correlated with the percentage of effector Treg subset. Smoking patients harboured higher percentages of the PD‐1⁺CD8⁺ T cell subset compared with non‐smoking patients. This study demonstrated that circulating antigen‐activated CD8⁺ T cells accumulated in lung cancer patients along with increased effector Treg and thoracic tumour burden. These findings aid a better understanding of immune‐host interactions in lung cancer patients using peripheral blood, and further support immunotherapeutic intervention strategies using combination therapy for differential control of Treg and activation of tumour‐specific effector T cells.     

Expression and functional perspectives of miR-184 in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignant tumors, with its 5-year survival rate lower than 5%. MicroRNAs (miR) have been known as important regulators for the tumorigenesis, progression, invasion and metastasis of various cancers. MiR-184 was found to be abnormally expressed in various cancers including glioma and oral carcinoma. The expression and functional role of miR-184 in PDAC, however, remains unclear. PDAC cell line PANC-1 was transfected with miR-184 inhibitor. Real-time PCR was used to detect the expression of miR-184 in untreated PANC-1, miR-184 inhibitor transfected PANC-1 and controlled normal pancreatic ductal epithelial cell line HPDE6c7. MTT assay was used to detect the effect of miR-184 on the proliferation of PANC-1 cells, while invasion assay and Western blotting were employed to describe the effect on cell invasion ability and expression of caspase-3, respectively. In PANC-1 cells, miR-184 was abundantly expressed. The transfection of inhibitor effectively suppressed the expression of miR-184, and further inhibited both cell proliferation and invasion abilities, in addition to the up-regulation of pro-apoptotic protein caspase 3 expression. The up-regulation of miR-184 in PDAC may facilitate the proliferation and invasion ability, and inhibit apoptosis of tumor cells, thus potentiating the occurrence and development of PDAC. MiR-184, therefore, is a potential molecular target for therapy.     

Expression of natural killer cell regulatory microRNA by uveal melanoma cancer stem cells

Natural killer (NK) cells are implicated in the control of metastasis in uveal melanoma, a process that has been ascribed to its cancer stem cell subpopulation. NK cell activation is regulated by specific microRNA (miR). The NK cell sensitivity and regulatory miR production of uveal melanoma cancer stem cells was examined. Cancer stem cells enriched from aggressively metastatic MUM2B uveal melanoma cells by selecting CD271⁺ cells or propagating as non-adherent spheres in stem-cell supportive were more resistant to NK cell cytolysis than cancer stem cells enriched from less aggressively metastatic OCM1 uveal melanoma cells. Both MUM2B and OCM1 cells expressed and secreted NK cell regulatory miRs, including miR 146a, 181a, 20a, and 223. MUM2B cells expressed and secreted miR-155; OCM1 cells did not. Transfecting MUM2B cells with anti-miR-155 increased NK cell sensitivity. CD271⁺ cells were identified in the blood of patients with metastatic uveal melanoma and were characterized by low expression of melanocyte differentiation determinants and by the ability to form non-adherent spheres in stem-cell supportive media. These cells also expressed NK cell regulatory miRs, including miR-155. These results indicate that uveal melanoma cancer stem cells can vary in their sensitivity to NK cell lysis and their expression of NK cell regulatory miRs. Circulating CD271⁺ cells from patients with metastatic uveal melanoma manifest cancer stem cell features and express miRs associated with NK cell suppression, including miR-155, that may contribute to metastatic progression.