miR-21 regulates the proliferation, invasion and radiosensitivity of cervical cancer HeLa cells by targeting RECK / 中华放射肿瘤学杂志

Objective:To explore the effect of miR-21 on cell proliferation, apoptosis, invasion and radiosensitivity of cervical cancer HeLa cells and unravel the underlying mechanism.Methods:RT-qPCR assay was used to detect the expression levels of miR-21 in cervical cancer tissues and adjacent non-tumor tissues, normal cervical epithelial cells (H8) and cervical cancer cell lines (HeLa, SiHa, ME180). HeLa cell line with inhibition of miR-21 or knockdown of RECK were constructed. CCK-8, Caspase3/7 live cell apoptosis detection, wound healing test, Transwell invasion, clone formation assay, Western blot and immunofluorescence were performed to detect cell viability, apoptosis, migration, invasion, radiosensitivity and related proteins. The dual luciferase assay verified whether miR-21 targeted RECK.Results:MiR-21 level in the cervical cancer tissues was significantly higher than that in its corresponding adjacent non-tumor tissues ( P<0.05). The expression levels of miR-21 in cervical cancer cell lines HeLa, SiHa and ME180 were significantly up-regulated compared with those in normal cervical epithelial cells H8(all P<0.05). MiR-21 knockdown significantly inhibited HeLa cell viability, promoted cell apoptosis, reduced radiation tolerance, down-regulated the expression of Cyclin D 1,Bcl-2, MMP-2 and MMP-9, and up-regulated the expression P21 and Bax proteins (all P<0.05). miR-21 targeted the 3’-UTR of RECK mRNA and negatively regulated the expression of RECK. Silencing RECK reversed the effects of miR-21 knockdown on HeLa cell apoptosis, migration, invasion and radiosensitivity. Conclusions:Inhibiting the expression of miR-21 significantly decreases cell viability, induces cell apoptosis, weakens cell migration and invasion capabilities, and enhances the radiosensitivity of HeLa cells. The potential mechanism is closely related to the targeted up-regulation of RECK.

RECK and TIMP-2 mediate inhibition of MMP-2 and MMP-9 by Annona muricata

Up-regulation of MMP-2 and MMP-9 plays a significant role in promoting cancer progression by degradingthe components of the extracellular matrix, thereby enhancing the migration of tumor cells. Although the antiproliferative and apoptotic effect of Annona muricata is well established, its effect on MMP-2 and MMP-9, amajor target in several types of cancers, has not been studied. Powdered samples of various parts of A.muricata like fruit, stem, seed, and twig extracted using aqueous methanol showed significant dose-dependentinhibition of MMP-2 and MMP-9 in a highly metastatic fibrosarcoma cell line, HT1080. Additionally, theseextracts also up-regulated the expression of several endogenous inhibitors of MMP-2 and MMP-9 likeREversion-inducing Cysteine-rich protein with Kazal motifs (RECK) and Tissue Inhibitor of Metalloproteinase-2 (TIMP-2). Furthermore, primary cells developed from tumor tissues obtained from patients notexposed to chemotherapy, also exhibited similar results. Remarkably, the inhibition of MMP-2 and MMP-9observed was tumor specific, with the A. muricata fruit extract showing only 2% inhibition in cells obtainedfrom normal tissues, when compared to 60% inhibition observed in cells obtained from tumor samples. Thepresent study elucidates a novel mechanism by which A. muricata extracts selectively exhibit their anti-canceractivity in tumor cells by down-regulating MMP-2 and MMP-9 that are important biomarkers in cancer.

miR-128 affects biological behavior of breast cancer cells through the targeting of RECK / 局解手术学杂志

Objective To investigate the biological behavior of breast cancer cells induced by miR-128 targeting RECK and its possible mechanism.Methods The expression of miR-128 in cell lines and transfection efficiency of lentiviral were detected by Western blot.Flow cytometry was used to detect the effect of miR-128 on the apoptosis of breast cancer cells.The dual luciferase assay was used to detect the in-teraction of miR-128 and RECK in breast cancer cells.Flow cytometry was used to detect the reversal effect of RECK on miR-128 in the cell cycle and colony formation of breast cancer cells.Results The expression of miR-128 in MCF-7 cells was 3.05 times that of NC cells,and the lentiviral transfection efficiency was obvious.miR-128 inhibits the growth of MCF-7 cells by inducing apoptosis and inhibiting cell cycle progression.RECK was the direct target of miR-128,and miR-128 directly regulated the expression of RECK.RECK ectopic recovery,miR-128 on breast cancer cell apoptosis and cell cycle inhibition had also been partially restored.Conclusion miR-128 plays an important role in the development and progression of breast cancer.It can interact with RECK to regulate the biological behavior of breast cancer cells,which suggests that miR-128 and RECK may be the potential therapeutic targets of breast cancer.

Alterations in the expression and activity of extracellular matrix components in HPV-associated infections and diseases

Infection with human papillomaviruses is associated with a series of benign and malignant hyperproliferative diseases that impose a heavy burden on human populations. A subgroup of mucosal human papillomavirus types are associated with the majority of cervical cancers and a relevant fraction of vulvar, vaginal, anal, penile and head and neck carcinomas. Human papillomaviruses mediate cell transformation by the expression of two pleiotropic oncoproteins that alter major cellular regulatory pathways. However, these viruses are not complete carcinogens, and further alterations within the infected cells and in their microenvironment are necessary for tumor establishment and progression. Alterations in components of the extracellular matrix for instance, matrix metalloproteinases and some of their regulators such as tissue inhibitors of metalloproteinases, have been consistently reported in human papillomaviruses-associated diseases. Matrix metalloproteinases function by remodeling the extracellular matrix and alterations in their expression levels and/or activity are associated with pathological processes and clinical variables including local tumor invasion, metastasis, tumor relapse and overall patient prognosis and survival. In this review we present a summarized discussion on the current data concerning the impact of human papillomavirus infection on the activity and expression of extracellular matrix components. We further comment on the possibility of targeting extracellular matrix molecules in experimental treatment protocols.

Progress in epigenetic regulation of the tumor suppressor gene RECK / 肿瘤研究与临床

The RECK protein is highly expressed in normal cells and tissues,however,down-regulated in transformed cells or tumor tissues.Subsequent functional studies have demonstrated that RECK owns the tumor suppressor activity.Hence,it is urgent and important to unmask the mechanisms involved in regulation of RECK expression.Epigenetic regulation plays a vital role in modulating gene expression,besides,multiple research also suggested the involvement of epigenetic regulation in RECK expression.The epigenetic regulation mechanisms of controlling the gene expression currently known will be reviewed in this paper.

The effects of 5-aza-2-deoxycytidine on RECK gene expression and invasion of salivary adenoid cystic car-cinoma cells / 实用口腔医学杂志

Objective:To investigate the effects of 5-aza-2′deoxycytidine(5-aza-dC),a DNA methyltransferase (DNMT)inhibitor, on the methylation status of the RECK gene and the invasion of salivary adenoid cystic carcinoma cell lines.Methods:Methylation-specific PCR,Western blot analysis and quantitative real-time PCR were used to investigate the methylation status of RECK gene and the expression of RECK mRNA and protein in SACC cell lines.The invasive ability of SACC cells was examined by transwell assay. Results:Promoter methylation was only found in ACC-Mcell line and not in ACC-2 cell line.Treatment of ACC-Mcells with 5-aza-dC partially reversed the hypermethylation status of the RECK gene and significantly enhanced the expression level of mRNA and pro-tein of RECK,suppressed ACC-Mcell invasive ability.Conclusion:5-aza-dC can inhibit ACC-Mcell invasion by reversal of hyperm-ethylation status of RECK gene.

Mecanismos de regulação epigenética e heterogeneidade tumoral clonal em melanoma metastático humano envolvendo gene RECK / Mechanisms of epigenetic regulation and tumor clonal heterogeneity in human metastatic melanoma involving RECK gene

Os pacientes com melanomas, em geral, apresentam extrema quimiorresistência e prognóstico ruim, com taxa de sobrevida de aproximadamente seis meses; portanto, novas estratégias terapêuticas são necessárias. As células deste tipo de tumor acumulam alterações na expressão gênica que contribuem para a proliferação descontrolada, evasão de senescência e inibição de morte celular em múltiplas rotas intracelulares. No Capítulo 1, foi explorado o controle epigenético do supressor tumoral RECK. Esse gene é largamente expresso em tecidos normais, com correlação de sua expressão com melhor prognóstico. Em tumores, RECK é inibido, incluindo em melanoma. Neste estudo, sua inibição por hipermetilação do promotor e remodelamento da cromatina por HDACs não foi o único fator inibitório nas linhagens de melanoma analisadas. Mesmo após a utilização a remoção de marcas epigenéticas associadas ao silenciamento gênico, a expressão proteica não pôde ser recuperada nas linhagens utilizadas neste trabalho. No Capítulo 2, isolou-se subpopulações clonais ao acaso a fim de modelar a heterogeneidade tumoral intrínseca. Neste modelo experimental, caracterizamos a presença de dois perfis tumorais subclonais: uma mais proliferativa, invasiva e sensível a vemurafenibe; e outra menos proliferativa, mais resistente e com maior expressão de RECK e fatores ligados a EMT. Nossos resultados, em conjunto, mostraram que as linhagens celulares parentais utilizadas apresentam diferenças entre si quanto à viabilidade celular, indução de apoptose e fosforilação de ERK após o tratamento com vemurafenibe. Segundo o nosso modelo, a resistência intrínseca ao vemurafenibe está presente e reflete a heterogeneidade do tumor inicial. Com estes resultados, pretendemos contribuir para o conhecimento sobre a composição clonal presente na heterogeneidade tumoral, além de contribuir para a função de RECK na biologia do melanoma

Patients with melanoma often present extreme chemoresistance and poor prognosis, with survival rates of approximately six months; therefore, new therapeutic strategies are necessary. Melanoma cells accumulate genotypic changes that contribute to uncontrolled proliferation, evasion of senescence and cell death inhibition in multiple cellular pathways. In Chapter 1, we have explored the epigenetic control of the tumor suppressor RECK. This gene is widely expressed in normal tissues, with correlation of its expression with better prognosis. In tumors, RECK is inhibited, including melanoma. Here, RECK inhibition by promoter hypermethylation and chromatin remodeling by HDACs was not the only inhibiting factor in the melanoma cell lines analyzed. Even after removing the epigenetic marks associated to gene expression silencing, the protein expression could not be recovered in the cell lines used in this study. In Chapter 2, it has been isolated several tumor clonal subpopulations in order to modulate the intrinsic tumor heterogeneity. In this experimental model, we have characterized the presence of two tumor subclonal profiles: a more proliferative, invasive and sensitive to Vemurafenib; and other less proliferative, less sensitive to Vemurafenib and presenting more expression of RECK and factors associated to EMT. Our results together have showed the parental cell lines used here differed from each other in terms of cell viability, induction of apoptosis, and ERK phosphorylation after treatment with Vemurafenib. According to our model, the intrinsic resistance to Vemurafenib is present and reflects the heterogeneity of the initial tumor. With these results, we intend to contribute to the knowledge of the tumor clonal subpopulations composition in tumor heterogeneity, and contributes to the RECK function in melanoma biology.

Effects of 5-aza-2′deoxycytidine on RECK gene expression and tumor invasion in salivary adenoid cystic carcinoma

Reversion-inducing cysteine-rich protein with kazal motifs (RECK), a novel tumor suppressor gene that negatively regulates matrix metalloproteinases (MMPs), is expressed in various normal human tissues but downregulated in several types of human tumors. The molecular mechanism for this downregulation and its biological significance in salivary adenoid cystic carcinoma (SACC) are unclear. In the present study, we investigated the effects of a DNA methyltransferase (DNMT) inhibitor, 5-aza-2′deoxycytidine (5-aza-dC), on the methylation status of the RECK gene and tumor invasion in SACC cell lines. Methylation-specific PCR (MSP), Western blot analysis, and quantitative real-time PCR were used to investigate the methylation status of the RECK gene and expression of RECK mRNA and protein in SACC cell lines. The invasive ability of SACC cells was examined by the Transwell migration assay. Promoter methylation was only found in the ACC-M cell line. Treatment of ACC-M cells with 5-aza-dC partially reversed the hypermethylation status of the RECK gene and significantly enhanced the expression of mRNA and protein, and 5-aza-dC significantly suppressed ACC-M cell invasive ability. Our findings showed that 5-aza-dC inhibited cancer cell invasion through the reversal of RECK gene hypermethylation, which might be a promising chemotherapy approach in SACC treatment.

Effect of miR-182 in non small cell lung cancer via regulating the reck signaling pathway / 解放军医学杂志

Objective To explore the effect of miR-182 in non small cell lung cancer (NSCLC) and its mechanism. Methods The expression level and difference of miR-182 were detected by qRT-PCR in NSCLC cell line and matched tissues of 30 patients suffering from NSCLC. Cell proliferation, invasion and metastasis of A549 and H1299 via miR-182 was detected by miR- 182 mimics. The predicted target gene (RECK) of miR-182 was identified via luciferase activation assay. The mRNA or protein expression of RECK after miR-182 mimic or inhibitor transfection was detected by qRT-PCR or Western blotting, respectively. Results Expression of miR-182 was significantly increased in NSCLC tissues and cell lines compared with that in the adjacent tissues (P<0.01), and it was correlated with the metastasis of NSCLC. The cell proliferation, invasion, and migration capacity was increased after miR-182 mimics transfection. Dual luciferase assay showed that miR-182 directly regulated the RECK translation level. RECK expression level was decreased after miR-182 mimics transfection in the A549 cells, while increased after miR-182 inhibitor transfection. Conclusion miR-182 promoted tumor growth and metastasis of NSCLC by down-regulating the RECK expression.

Effect of miR-374b-5p targeting RECK gene on xenogenic human gastric cancer in nude mice / 肿瘤

Objective: To investigate the role of microRNA-374b-5p (miR-374b-5p) and its target gene reversion-inducing-cysteine-rich protein with Kazal motifs (RECK) in occurrence and development of gastric cancer. Methods: The human gastric cancer MGC-803 cells were used to establish BABL/c nude mice model bearing xenografts of MGC-803 cells. The mice were randomly divided into three groups when the volume of the xenograft reaching about 60 mm3: blank control group (n = 5), negative control (NC) group (transfecion with miR-374b-5p NC-inhibitor every four days) (n = 5) and miR-374b-5p inhibitor group (transfecion with miR-374b-5p inhibitor every four days) (n = 5). The growth of the xenografts was observed. The mice in each group were sacrificed three days after the end of last transfection (on the 35th day after transplantation of MGC-803 cells). The pathological features of the xenografts were observed by hematoxylin-eosin (HE) staining. The expression level of miR-374b-5p in xenografts in nude mice after transfection was determined by real-time fluorogenic quantitative-PCR (RFQ-PCR). The Luciferase Activity Assay was used to determine whether miR-374b-5p was targeting RECK gene. The expressions of RECK mRNA and protein were detected with RFQ-PCR and immunohistochemistry, respectively. Results: The tumor xenograft volume of miR-374b-5p inhibitor group was significantly smaller than those of the blank control group and NC group since the 9th day after transfection (since the 23th day after the beginning of transplantation) (P < 0.05), but the xenograft volume of the blank control group and the NC group had no significant difference. Pathological results indicated that the degree of malignancy of xenografts in miR-374b-5p inhibitor group was lower than those of the other two groups. The expression level of miR-374b-5p in miR-374b-5p inhibitor group was significantly lower than those in the other two groups (both P < 0.05). The miR-374b-5p directly targeting RECK gene was proved by Luciferase Activity Assay. The mRNA and protein expressions of RECK in miR-374b-5p inhibitor group were both significantily higher than those in the other two groups (all P < 0.05). Conclusion: miR-374b-5p may play as an oncogene in the occurrence and development of gastric cancer through RECK pathway.

Correlation between RECK gene methylation status and radiosensitivity in laryngeal squamous cell carcinoma / 中国肿瘤临床

Objective:This study has two objectives. One is to detect the methylation status of reversion-inducing cysteine-rich protein with Kazal motifs (RECK, a new tumor suppressor gene) gene promoter in primary laryngeal squamous cell carcinoma and nor-mal laryngeal mucosa. The other is to analyze the correlation between RECK gene methylation status and radiosensitivity in laryngeal squamous cell carcinoma. Methods:Methylation-specific polymerase chain reaction was used to detect the RECK gene methylation of 70 specimens of laryngeal squamous cell carcinoma and 15 normal tissues of laryngeal mucosa. The patients underwent six cycles of ra-diotherapy and were followed-up for 5 years. The correlation between RECK gene methylation status and radiosensitivity in laryngeal squamous cell carcinoma was analyzed. Results: After six cycles of radiotherapy, 47 patients (67.14%) showed sensitivity and 23 (32.86%) showed tolerance to radiotherapy. The methylation level of the RECK gene was lower in the radiation-sensitive group than in the nonradiation-sensitive group (P<0.05). The methylation level of the RECK gene was lower in the remission group than in the non-remission group. RECK gene methylation could increase the risk of cancer by approximately 5.010 times (OR=5.010, 95%CI:1.616-15.533). Conclusion:RECK gene promoter methylation in human laryngeal squamous cell carcinoma is an early event that is correlated with the patient's sensitivity to radiotherapy. Thus, the patient's sensitivity to radiation can be predicted by detecting the meth-ylation status of the RECK gene promoter.

Negative expression of RECK indicates unfavorable clinical outcome for breast cancer / 实用肿瘤学杂志

Objecive To explore the significance of RECK expression in breast cancer .Methods Im-munohistochemical staining was used to analyze RECK expression levels in patients with breast cancer .We com-pared these data with the clinicopathological features of these patients .Rseults Breast cancer patients with nega-tive RECK expression had significantly lower DFS and 5-year survival rates than patients with positive RECK expression.In addition,for node-negative breast cancer ,negative RECK expression indicated markedly unfavor -able survival rate than positive arm .Multivariate analysis further confirmed that RECK expression was an inde -pendent prognostic factor for patients with breast cancer .Conclusion The loss of RECK expression indicates un-favorable survival rate for patients with breast cancer .RECK expression is a new ,important risk factor for recur-rence in breast cancer .

Isolamento, expressão, e caracterização de três variantes de splicing do gene supressor de tumor RECK em modelo de astrocitoma humano / Isolation, expression, and characterization of three alternatively spliced variants of the RECK tumor suppressor gene in the human astrocytoma model

Glioblastoma multiforme (G BM), ou astrocitoma grau IV, é o tumor mais comum e letal do sistema nervoso central. Uma de suas características mais marcantes é seu alto potencial invasivo do tecido normal adjacente. Neste processo, o remodelamento da matriz extracelular, modulado por enzimas que degradam seus componentes e por inibidores destas enzimas, é crucial. Foi descrito que a expressão de MMP-2 e MMP-9, membros da família das metaloproteinases de matriz, aumentam conforme a progressão de astrocitomas. A variante canônica de RECK suprime a invasão tumoral e metástase através da inibição da atividade de, pelo menos, três MMPs: MMP-2, MMP-9 e MMP-14. Uma correlação positiva tem sido observada entre a abundância da expressão de RECK em amostras tumorais e um prognóstico mais favorável para pacientes com diversos tipos de tumores. Neste estudo, variantes de splicing do gene supressor de tumor RECK foram identificadas através da análise de Expressed sequenced Tags (ESTs), isoladas por RT-PCR, sequenciadas e clonadas. Três novas variantes de splicing do gene RECK foram identificadas e caracterizadas. O perfil de expressão dos transcritos de RECK foi determinado através de ensaios de RT-PCR quantitativo em um painel de tecidos normais e, também, durante a progressão de astrocitomas. Foram utilizadas, para esta análise, amostras macro dissecadas de tumores de pacientes com astrocitomas grau I (n=15), II (n=15), III (n=15) e GBMs (n=30). Os resultados mostram que maior expressão de RECK canônico, acompanhada de maior razão de expressão da variante canônica em relação às variantes de splicing alternativo, correlaciona positivamente com maior sobrevida global de pacientes com GBM, sugerindo seu papel como potenciais biomarcadores para o prognóstico destes pacientes. Análise funcional das isoform as de RECK em células U87 MG revelou que as células superexpressando as isoformas não apresentam inibição do processo de invasão celular, como observado para superexpressão da proteína canônica. Dentre as isoformas analisadas, destaca-se RECK-B, isoforma potencialmente ancorada à membrana plasmática por GPI, como a proteína canônica RECK, sugerindo uma possível colocalização destas variantes. Observa-se que células superexpressando RECK-B apresentam maior capacidade tumorigênica. Os resultados indicam que as variantes de RECK e o balanço entre a expressão destas variantes, apresentam um papel importante no comportamento e na agressividade de GBMs, tendo potencial valor na clínica. Além disso, para abrir perspectivas para o estudo das variantes de RECK, o balanço de expressão dos transcritos canônico e alternativos deste gene foi explorado durante os processos de diferenciação osteogênica e adipogênica. Os resultados indicam que a expressão da variante canônica é mais abundante em relação à expressão de suas isoformas em estágios tardios da adipogênese, sendo que o perfil inverso é observado em relação à isoforma B durante a osteogênese, sugerindo que o balanço entre os níveis de expressão das isformas de RECK possui um potencial papel biológico que deve ser explorado durante esses processos. Em conjunto, os resultados demonstram a existência de, pelo menos, três variantes de splicing do gene supressor de tumor RECK com envolvimento na tumorigênese e na diferenciação celular, abrindo novas perspectivas para o estudo e a aplicação do gene RECK na clínica

Glioblastoma multiforme (GBM) or grade IV astrocytoma is the most common and lethal tumor of the central nervous system. One of the most striking features of GBMs is their invasive potential of the normal surrounding brain tissue. It has been described that MMP-2 and MMP-9 expression levels increase during astrocytoma progression. Canonical RECK suppresses tumor invasion and metastasis by negatively regulating at least three matrix metalloproteinases, namely: MMP-9, MMP-2 and MT1-MMP. A positive correlation has been observed between the abundance of RECK express ion in tumor samples and a more favorable prognosis for patients with several types of tumors. In this study, splice variants of the RECK tumor suppressor gene were identified by Expressed Sequence Tag (EST) analysis, isolated by RT-PCR, sequenced and cloned. Three novel alternatively spliced variants of the RECK tumor suppressor gene were identified and characterized. The RECK transcripts expression profiles were investigated using quantitative RT-PCR assays in a normal tissue RNA panel and, also, during astrocytoma progression in macrodissected tumor samples of patients with astrocytoma grades I (n=15), II (n=15), III (n=15) and IV/GBM (n=30). The results show that higher canonical RECK expression, accompanied by a higher ratio of canonical to alternative transcript expression, positively correlated with higher overall survival rate after chemotherapeutic treatment of GBM patients. Our findings suggest that these RECK transcript variants may potentially be used as biomarkers for prognosis of GBM patients. U87 MG cells overexpressing each RECK alternative variant were generated and found to lack the supressive role of cellular invasion processes found upon overexpressing the canonical protein. Among the characterized isoforms, RECK-B stands out, since this isoform is potentially anchored to the cell membrane by a GPI anchor, exactly as the canonical RECK and, also, since cells overexpressing RECK-B display greater tumorigenic capacity. The results indicate that RECK variants and the balance between the expressions of these variants, play an important role in the behavior and aggressiviness of GBMs, therefore have a potential translational application. In addition, in order to investigate new perspectives for the analysis of these isoforms, the expression balance of RECK transcripts was assessed during osteogenesis and adipogenesis, by qRT - PCR. The results show that the expression of the canonical RECK variant is more abundant that that of its alternative isoforms in later stages of adipogenic differentiation. The opposite profile is found regarding RECK-B during osteogenesis, suggesting that the balance between the expressions of these transcripts may have a potential role during these processes. Taken together, the results show the existence of, at least, three alternatively spliced variants of the RECK tumor suppressor gene, which are involved in tumogigenesis and cellular differentiation, o pening new perspectives for studies and clinical application of the RECK gene

Correlation between RECK gene methylation and the prognosis of laryngeal squamous cell carcinoma / 医学研究生学报

Objective The incidence of laryngeal cancer has characteristic of regional differences, but the etiology is not clear. The aim of this study was to analyze the correlation between RECK gene promoter methylation and prognosis of laryngeal squamous cell carci-noma patients through detecting the RECK gene methylation status of primary laryngeal squamous cell carcinoma and adjacent tissues . Methods Methylation specific PCR assay was used to detect the RECK gene promoter methylation status of 70 laryngeal squamous cell carci-noma specimens in our hospital from July 2006 to Dcember 2007, and the differences of methylation status with different pathological parame-ters were compared.The correlation between RECK gene promoter methylation and prognosis of 64 patients completed five-year follow-up was analyzed. Results The RECK gene methylation rate (86.67%) of patients with poor differentiation in tumor cells was much higher than that of the patients with a moderate and better tumor cell differentiation (43.64%) (P<0.05).In 29 pairs of laryngeal cancer-adjacent tis-sues specimens matches, the RECK gene methylation in laryngeal carcinoma (55.12%) was higher than normal tissues (27.59%) ( P=0.029).RECK gene methylation significantly shortened the tumor free survival and overall survival analyzed by Log-rank (P=0.024, P=0.017).Lymph node metastasis and clinical stage in classⅢ-Ⅳsignificantly shortened the tumor free survival and overall survival (P=0.029, P=0.024;P=0.033, P=0.032).Moderate and better tumor cell differentiation significantly shortened the tumor free survival (P=0.024, P=0.049).Lymph node metastasis, clinical stage, and RECK gene methylation were independent risk factors of overall survival. Conclusion RECK gene promoter methylation in human laryngeal squamous cell carcinoma is an early event and may occur in the adjacent normal tissues, predicting a poor prognosis in patients.

Effects of suppressing the expression of miRNA-21 on the apoptosis and invasion abilities of cholangiocarcinoma cells and its target gene / 中华肝胆外科杂志

ObjectiveTo discuss the effects of apoptosis and invasion of RBE cells caused by miRNA 21 suppression and further investigate the potential role of miRNA-21 plays on target mRNA regulation. MethodsThe RNAi technology was employed to suppress the expression of RBE cells.The changes in RECK mRNA and protein expressions were detected by RT-PCR and Western blotting respectively. Changes occurred in apoptosis was closely monitored by flow cytometry (FCM). The invasion of RBE cells was analyzed in vitro by invasion assay (transwell). ResultsThe expression of miRNA-21 was clearly suppressed while the RECK mRNA and protein were over-expressed. The rate of apoptosis was significantly accelerated and there was a dramatic decrease in RBE cells' ability to invade after miRNA-21 knockdown. ConclusionThrough miRNA-21 suppression, the rate of apoptosis of RBE cells was accelerated whereas their invasion ability was greatly reduced. RECK was found to be the target gene of miRNA-21 which participates in the regulation process of regulation.

Papel de TGF[BETA]-1 na regulação da expressão de MMPs seus inibidores (TIMPs e Reck) em modelo de carcinoma mamário humano: análise funcional de RECK e sua correlação com dados clínico-patológicos / Role of TGF[BETA]-1 as a common regulator of MMPs and their inhibitors (TIMPs e RECK) in human breast cancer cell model: functional analysis of RECK and its correlation with clinical-pathological

A causa de morte da maioria das pacientes com câncer de mama se deve à doença metastática desenvolvida a partir do tumor primário. A degradação dos componentes da matriz extracelular (MEC), um dos principais eventos do processo metastático, é regulada pelo balanço entre as atividades das metaloproteinases de matriz (MMPs) e dos seus inibidores, tanto os inibidores teciduais (TIMPs) como o inibidor associado à membrana (RECK). Contudo, ainda existe pouca informação sobre os mecanismos moleculares responsáveis pela manutenção deste balanço. No presente trabalho, foi investigado o envolvimento de TGF-β1 (Transforming Growth Factor-β1), uma citocina multifuncional é capaz tanto de inibir o crescimento celular, quanto de promover invasão e metástase, dependendo do estadiamento e do tipo de tumor, na regulação da expressão de MMPs, TIMPs e RECK, em modelo de câncer de mama. Primeiramente, examinou-se os níveis de expressão de mRNA das isoformas e receptores de TGF-β, em um painel de cinco linhagens de carcinoma mamário humano, com diferentes potenciais invasivos e metastáticos, por qRT-PCR. Os resultados obtidos demonstraram uma correlação positiva entre a expressão dessas moléculas, e a progressão do caráter invasivo e metastático celular. Em seguida, a linhagem altamente invasiva, MDA-MB-231, foi tratada com diferentes concentrações de TGF-β1 recombinante. Esta citocina foi capaz de modular a expressão gênica de MMPs (MMP-2 e MMP-9) e de seus inibidores (TIMP- 2 e RECK). Tanto ERK½, quanto p38MAPK mostraram-se envolvidas neste mecanismo. Foi demonstrado que a inibição da atividade de ERK½ alterou a expressão das proteínas MMP-9, TIMP-2 e RECK, enquanto o bloqueio de p38 MAPK afetou os níveis protéicos de MMP-2 e TIMP-2. O aumento do potencial migratório e invasivo da linhagem MDA-MB-231, induzido por TGF-β1, mostrou-se também dependente da atividade de MMPs, ERK½ e p38MAPK. Dada a ausência de informações sobre o papel de RECK em modelo...

The metastatic disease is the main mortality cause of breast cancer patients. The metastatic process involves a complex cascade of events, including the organized breakdown of the extracellular matrix (ECM) compounds. The degradation of ECM is tightly regulated by the balance between the activities of matrix metalloproteinases (MMPs) and their inhibitors, the tissue inhibitors (TIMPs) and the membrane-associated inhibitor (RECK). Among the several molecules released and activated by ECM remodeling, TGF-β1 (Transforming Growth Factor-β1) is a multifunctional cytokine able to regulate both cell growth inhibition and invasion and metastasis promotion, depending on the tumor stage and type. Since the molecular mechanisms involved in the ECM remodeling control are still not completed understood, in this study, we investigated the involvement of TGF-β1 in regulating of MMPs, TIMPs and RECK expression, in the breast cancer model. By qRT-PCR, we first examined the gene expression levels of TGF-β isoforms and receptors, in a panel of five human breast cancer cell lines displaying different degrees of invasiveness and metastatic potential. Our results suggest a positive correlation between the mRNA expression of these molecules and the breast cancer progression. Moreover, the highly invasive breast cancer cell line MDA-MB-231 was treated with different concentrations of recombinant TGF-β1. We described that this cytokine was able to modulate the gene expression of MMPs (MMP-2 and MMP-9) and MMPs inhibitors (TIMP-2 and RECK) at both the mRNA and protein levels, with ERK½ and p38 MAPK being involved in this molecular mechanism. However, while ERK½ activity inhibition altered MMP-9, TIMP-2 and RECK expression, the p38 MAPK blockage affected the protein levels of MMP-2 and TIMP-2. Finally, we reposted that the TGF-β1-enhanced migration and invasion capacities of MDA-MB- 231 cells were blocked by MMPs, ERK½ and p38 MAPK inhibitors. Analysis of the RECK function in the breast...

Papel de TGFß-1 na regulação da expressão de MMPs seus inibidores (TIMPs e Reck) em modelo de carcinoma mamário humano: análise funcional de RECK e sua correlação com dados clínico-patológicos / Role of TGFß-1 as a common regulator of MMPs and their inhibitors (TIMPs e RECK) in human breast cancer cell model: functional analysis of RECK and its correlation with clinical-pathological

A causa de morte da maioria das pacientes com câncer de mama se deve à doença metastática desenvolvida a partir do tumor primário. A degradação dos componentes da matriz extracelular (MEC), um dos principais eventos do processo metastático, é regulada pelo balanço entre as atividades das metaloproteinases de matriz (MMPs) e dos seus inibidores, tanto os inibidores teciduais (TIMPs) como o inibidor associado à membrana (RECK). Contudo, ainda existe pouca informação sobre os mecanismos moleculares responsáveis pela manutenção deste balanço. No presente trabalho, foi investigado o envolvimento de TGF-ß1 (Transforming Growth Factor-ß1), uma citocina multifuncional é capaz tanto de inibir o crescimento celular, quanto de promover invasão e metástase, dependendo do estadiamento e do tipo de tumor, na regulação da expressão de MMPs, TIMPs e RECK, em modelo de câncer de mama. Primeiramente, examinou-se os níveis de expressão de mRNA das isoformas e receptores de TGF-ß, em um painel de cinco linhagens de carcinoma mamário humano, com diferentes potenciais invasivos e metastáticos, por qRT-PCR. Os resultados obtidos demonstraram uma correlação positiva entre a expressão dessas moléculas, e a progressão do caráter invasivo e metastático celular. Em seguida, a linhagem altamente invasiva, MDA-MB-231, foi tratada com diferentes concentrações de TGF-ß1 recombinante. Esta citocina foi capaz de modular a expressão gênica de MMPs (MMP-2 e MMP-9) e de seus inibidores (TIMP- 2 e RECK). Tanto ERK½, quanto p38MAPK mostraram-se envolvidas neste mecanismo. Foi demonstrado que a inibição da atividade de ERK½ alterou a expressão das proteínas MMP-9, TIMP-2 e RECK, enquanto o bloqueio de p38 MAPK afetou os níveis protéicos de MMP-2 e TIMP-2. O aumento do potencial migratório e invasivo da linhagem MDA-MB-231, induzido por TGF-ß1, mostrou-se também dependente da atividade de MMPs, ERK½ e p38MAPK. Dada a ausência de informações sobre o papel de RECK em modelo mamário, a função deste inibidor de MMPs também foi investigada. Primeiramente, analisou-se a expressão de RECK ao longo do desenvolvimento da mama e, posteriormente, em 1040 amostras tumorais de mama humana, através da metodologia de Tissue Microarray, tendo sido possível demonstrar que a alta expressão de RECK associa-se a menor tempo de sobrevida global e livre de doença em 10 anos. Os resultados obtidos indicaram que a expressão da proteína RECK, em oposição ao verificado em outros tipos de tumores, está relacionada ao fenótipo mais agressivo de tumores de mama. Entretanto, a análise funcional de RECK, realizada por meio da utilização de vetores shRNA específicos para a inibição desta proteína, demonstrou que RECK também atua como um inibidor de invasão celular e da expressão de MMP-9, na linhagem MDA-MB-231. Em conjunto, os resultados obtidos neste trabalho contribuíram para a elucidação dos mecanismos moleculares de regulação de RECK, por clássicas moléculas associadas ao processo de tumorigênese (TGF-ß1 e MAPKs), bem como para o esclarecimento de suas funções em modelo mamário, sugerindo-o como mais um promissor candidato a marcador prognóstico e alvo molecular para a terapia do câncer de mama

The metastatic disease is the main mortality cause of breast cancer patients. The metastatic process involves a complex cascade of events, including the organized breakdown of the extracellular matrix (ECM) compounds. The degradation of ECM is tightly regulated by the balance between the activities of matrix metalloproteinases (MMPs) and their inhibitors, the tissue inhibitors (TIMPs) and the membrane-associated inhibitor (RECK). Among the several molecules released and activated by ECM remodeling, TGF-ß1 (Transforming Growth Factor-ß1) is a multifunctional cytokine able to regulate both cell growth inhibition and invasion and metastasis promotion, depending on the tumor stage and type. Since the molecular mechanisms involved in the ECM remodeling control are still not completed understood, in this study, we investigated the involvement of TGF-ß1 in regulating of MMPs, TIMPs and RECK expression, in the breast cancer model. By qRT-PCR, we first examined the gene expression levels of TGF-ß isoforms and receptors, in a panel of five human breast cancer cell lines displaying different degrees of invasiveness and metastatic potential. Our results suggest a positive correlation between the mRNA expression of these molecules and the breast cancer progression. Moreover, the highly invasive breast cancer cell line MDA-MB-231 was treated with different concentrations of recombinant TGF-ß1. We described that this cytokine was able to modulate the gene expression of MMPs (MMP-2 and MMP-9) and MMPs inhibitors (TIMP-2 and RECK) at both the mRNA and protein levels, with ERK½ and p38 MAPK being involved in this molecular mechanism. However, while ERK½ activity inhibition altered MMP-9, TIMP-2 and RECK expression, the p38 MAPK blockage affected the protein levels of MMP-2 and TIMP-2. Finally, we reposted that the TGF-ß1-enhanced migration and invasion capacities of MDA-MB- 231 cells were blocked by MMPs, ERK½ and p38 MAPK inhibitors. Analysis of the RECK function in the breast model was also an objective of this study. We analyzed RECK expression during mammary gland development. We evaluated the RECK protein profile in 1040 breast tumor tissue samples using Tissue Microarray assays. We demonstrated that high expression levels of RECK were associated with shorter overall and disease-free survival in 10 years. Moreover, we verified that RECK is a biomarker of poor prognosis mainly for patients diagnosed with less aggressive breast tumor. Therefore, in contrast to other tumor types, our results indicate that high protein expression levels of RECK are related to a more aggressive phenotype. In fact, the RECK functional analysis, performed by using of shRNA vectors, showed that RECK function remains as an inhibitor of cellular invasion and MMP-9 expression, in MDA-MB-231 cells. Taken together, our results contribute to better understanding of the molecular mechanisms associated to RECK regulation by TGF-ß1 and MAPK as well as to clarify its role in breast model. Thus, we suggests RECK as a new and promising prognostic marker and molecular target candidate for breast cancer therapy

Expression of reversion-inducing cysteine-rich protein with Kazal motifs and its relationship with matrix metalloproteinase-9 in prostate carcinoma tissues / 第二军医大学学报

Objective: To investigate the expression of the reversion-inducing cysteine-rich protein with Kazal motifs (RECK) and matrix metalloproteinase-9(MMP-9) in the prostate carcinoma tissues and to evaluate the role of RECK in the tumorigenesis of prostate carcinoma. Methods: Twenty specimens of prostate cancer and 12 specimens of normal prostate were harvested. RT-PCR and real-time RT-PCR were used to determine the expression of RECK mRNA and RT-PCR was used to determine the expression of MMP-9 mRNA in the specimens. Western blotting analysis was used to determine the expression of RECK protein. Results: It was found that the expression of RECK mRNA in the prostate carcinoma tissues was lower than that in the normal prostate tissues (P<0.01); MMP-9 expression in the prostate carcinoma tissues was significantly higher than that of the normal prostate tissues (P<0.01). Western blotting analysis showed that the expression of RECK protein in the carcinoma tissues was lower than that in the normal prostate tissue (P<0.01). Conclusion: RECK gene expression is lower in the prostate carcinoma tissues; RECK may inhibit the progression and metastasis of cancer through inhibiting MMP-9 expression.

Caracterização de metaloproteinases de matriz e reck em queratinócitos primários que expressam oncoproteínas do papilomavírus humano (HPV) / Characterization of matrix metalloproteinases and reck in primary keratinocytes that express human papillomavirus (HPV) oncoproteins

Os tumores da cérvice-uterina, que representam uma das principais doenças ginecológicas em mulheres na idade reprodutiva em todo o mundo, estão etiologicamente associados com a infecção pelo papilomavírus humano (HPV). A progressão de uma lesão intraepitelial escamosa de baixo-grau (LSIL) a um carcinoma invasivo de cérvix uterina está acompanhada da degradação da matriz extracelular (MEC) devido à ação progressiva das metaloproteinases de matriz (MMP-2, MMP-9 e MMP-14) no processo de invasão e metástase. Entretanto, o balanço entre as MMPs e seus reguladores como RECK e TIMPs é necessário para controlar esta invasão. O objetivo deste projeto consiste em avaliar a atividade e a expressão das metaloproteinases 2, 9, e 14, e caracterizar a expressão do gene supressor de metástase RECK e do inibidor tecidual de metaloproteinases (TIMP-2), em modelo de queratinócitos humanos infectados com retrovírus recombinantes que expressam os oncogenes E6 e/ou E7 de HPV 16, em culturas cultivadas em monocamada e organotípicas. Para isso, utilizamos ensaios de real-time PCR, zimografia, western blot, imunocitoquímica, ensaio de ELISA e imunohistoquímica. Em culturas em monocamada observamos que as células que expressam as oncoproteínas E6E7 de HPV16 apresentaram menores níveis protéicos de RECK e TIMP-2 em relação ao controle pXLSN. Quando analisamos as culturas organotípicas, também observamos esta diminuição dos níveis de RNAm e protéicos de RECK em rafts que expressam E6E7, acompanhado pelo aumento da atividade de MMP-9, em relação ao controle. Também observamos que o tratamento das culturas com a citocina TNF aumenta a expressão gênica, protéica e atividade de MMP-9 em todas as linhagens analisadas. Além disso, os oncogenes E6 e/ou E7 não afetam a expressão e/ou atividade de MMP-2, MT1-MMP. Nossos dados demonstraram que a expressão das oncoproteínas E6E7 de HPV16 estão relacionadas com o desequilíbrio entre MMPS e seus inibidores, sugerindo que em uma fase pré-invasiva do...

Cervical cancer is etiologically associated with to high-risk human papillomavirus (HPV) infection. It has been observed that matrix metalloproteinases (MMPs) -2, -9, and MT1-MMP are required for basement membrane degradation during cervical carcinoma progression. Moreover, a counterbalancing among MMPs and their regulators, such as TIMPs and RECK, is necessary to modulate invasion. In order to study the effect of HPV oncogenes on MMPs expression, primary human keratinocytes (PHKs) were infected with recombinant retroviruses expressing wild-type HPV16 E6 and/or E7 oncogenes and were used to seed monolayers and organotypic cultures. Quantitative real-time PCR (Q-PCR), western blot, zimography, immunocitochemistry, ELISA assay and immunohistochemistry were used to determine the expression level and activity of MMP-2, MMP-9, MT1-MMP and their inhibitors RECK and TIMP-2. We observed that cultures expressing E6E7 presented lower RECK and TIMP-2 protein levels than control keratinocytes. In addition, rafts cultures presented the same lower RECK levels additionally presenting higher MMP-9 activity than control. Furthermore, we observed that expression of E6 and/or E7 proteins do not affect MMP-2 and MT1-MMP protein levels and/or activity. We also observed that TNF treatment enhance the MMP-9 gene and protein expression and activity in all studied cell lines. Taken together, our results demonstrate that HPV16E6E7 expression is related with the unbalance between MMPs and their inhibitors, suggesting that in the initial steps of HPV-related cervical disease, not only MMPs but also RECK and TIMP-2 are critical for tumor progression.

Expression of RECK and MMP-9 in pancreatic cancer and its clinicopathological significance / 中华胰腺病杂志

Objective To investigate the expression of RECK and MMP-9 in pancreatic cancer and to explore the relationship between RECK, MMP-9 expression and the clinicopathological characteristics.Methods PV6000 immunohistochemical method was used to detect the expression of RECK and MMP-9 in 28 cases of pancreatic cancer and 10 cases of normal pancreatic tissue. All the statistical analyses were performed by using SPSS 13.0 statistical software to determine the relationship between RECK, MMP-9 expression and the clinicopathological characteristics. Results The overall positive rate of RECK espression was 46.43% (13/28)in pancreatic cancer, which was significantly lower than that in normal pancreatic tissue (90%, 9/10). The positive rate of RECK espression in Ⅰ + Ⅱ clinical stage (75.0% ,9/12) was significantly higher than that in Ⅲ + Ⅳ stage (25.0%, 4/16 P < 0.05 ). The positive rate of RECK expression in cases without distant metastases (60.0%, 12/60) was significantly higher than that in cases with distant metastasis (12.5%, 1/8,P<0.05). The overall positive rate of MMP-9 was 75% (21/28) in pancreatic cancer, and 20% (2/10) in normal pancreatic tissue. The comparison between these two groups indicated a significant difference (P <0.01 ). The positive rate of MMP-9 in Ⅰ + Ⅱ clinical stage(50.0% ,6/12) was significantly lower than that in Ⅲ + Ⅳ stage (93.8,15/16, P < 0.05). The positive rate of MMP-9 in well differentiation group(33.3%,1/3 ) was significantly lower than that in poor differentiation group ( 100%, 12/12 ,P < 0. 01 ). The expressionof RECK was negatively correlated with the expression of MMP-9 ( r = - 0. 536, P < 0.01 ). Conclusions RECK is lowly expressed in pancreatic cancer, but MMP-9 is highly expressed. RECK and MMP-9 may serve as important markers in the evaluation of tumor stage.