Identification of FLOT2 as a novel target for microRNA-34a in melanoma

PURPOSE

To confirm whether flotillin 2 (FLOT2) is a direct target of miR-34a and miR-34a/FLOT2 pathway plays a key role in melanoma proliferation and metastasis.

METHODS

First, miR-34a and FLOT2 expressions were both detected in human tissues and cell lines by qRT-PCR. Then, after transfection of mimics/inhibitor of miR-34a into melanoma cell lines, MTT, colony formation, scratch migration assays and transwell invasion assays were performed to evaluate the impact of miR-34a on cell proliferation and metastasis. Western blot, qRT-RCR and dual luciferase reporter gene assays were carried out to confirm whether FLOT2 is a direct target gene of miR-34a. In functional recovery experiments, proliferation and metastasis ability of WM35 and WM451 was tested after being co-transfected with miR-34a inhibitor/si-FLOT2 or miR-34a mimics/FLOT2 cDNA to confirm that FLOT2 is downregulated by miR-34a.

RESULTS

The miR-34a significantly lower-expressed in metastasis melanoma tissues compared to in situ melanoma, nevi and normal skin whereas FLOT2 has an opposite trend. The level of miR-34a and FLOT2 in different melanoma cell lines was also tested and found that metastatic melanoma cell lines has lower miR-34a expression and higher FLOT2 expression compare to in situ melanoma cell line. MiR-34a overexpression profoundly inhibits WM451 cell proliferation and metastasis, whereas miR-34a reduction had a promoting effect to proliferation and metastasis of WM35. Results of Western blot, qRT-RCR and dual luciferase reporter gene assays revealed that FLOT2 is a direct target gene of miR-34a. Furthermore, overexpression/blockage of FLOT2 could attenuate effect of miR-34a overexpression/inhibition which indicated miR-34a suppresses melanoma biological behavior partially through FLOT2 inhibition.

CONCLUSIONS

Our study confirmed that miR-34a is involved in the tumor inhibition of melanoma by directly targeting FLOT2 gene. This finding provides potential novel strategies for therapeutic interventions of melanoma.

Mesenchymal stem cells regulate cytoskeletal dynamics and promote cancer cell invasion through low dose nitric oxide

Bone marrow-derived mesenchymal stem cells (BMSCs) can be recruited to tumor sites and integrate into the stroma of tumors. When co-cultured with BMSCs, otherwise weakly metastatic nasopharyngeal carcinoma cells (NPC) showed improved metastatic ability. BMSCs in the tumor environment displayed the characteristics of macrophages. Nitric oxide produced by BMSCs in tumor environment could translocate caldesmon to podosome in Ca2+/calmodulin manner and promoted metastatic ability of NPC cells through invadopodia formation, with which the NPC cells degrade the extracellular matrix. Thus, we concluded that the BMSCs promoted cell migration and invasion through nitric oxide-induced paracrine signals.

Upregulation of cytoskeleton protein and extracellular matrix protein induced by stromal-derived nitric oxide promotes lung cancer invasion and metastasis

Lung cancer commonly metastasizes to lymph nodes, brain and bones, which is the main cause of death. It is still a challenge to detect molecular biomarkers for early diagnosis and therapeutics of lung cancer. Our previous study found that bone marrow-derived stroma cells (BMSCs) under tumor microenvironment produced nitric oxide (NO), which was induced by inducible nitric oxide synthase (iNOS), and promoted invasion and metastasis of cancer cells by remodeling cytoskeleton. The aim of this study is to elucidate the relationship between the expressions of iNOS, cytoskeleton protein caldesmon, OPN, and clinical parameters especially the metastasis of lung cancer. We found that nitric oxide can remodel cytoskeleton and promoted the mobility of lung cancer cells. The expressions of iNOS, caldesmon, and OPN are closely correlated to metastasis of lung cancer. The intracranial metastatic tissue samples of lung cancer showed significantly higher expression of iNOS, caldesmon and OPN. A flow-cytometry analysis for peripheral blood of lung cancer patients showed increased EPCAM+/OPN+ cells in circulation of patients with bone metastasis compared to that of patients without metastasis, which is indicative of cancer circulating cells. The concentration of serum OPN was also positively related to the bone metastasis of lung cancer. Taken together, these results suggested that iNOS, caldesmon and OPN may work as biomarkers for metastasis of lung cancer.

MicroRNA-195 functions as a tumor suppressor by inhibiting CBX4 in hepatocellular carcinoma

MicroRNA-195 (miR-195) plays important roles in tumor metastasis and angiogenesis, yet its function and mechanism of action in hepatocellular carcinoma (HCC) remain to be elucidated. In this study, we aimed to confirm whether chromobox homolog 4 (CBX4) is a direct target gene of miR-195 and determine the functions of miR-195 through the CBX4 pathway. miR-195 expression was slightly lower in the HCC tissues compared with that in the adjacent normal tissues. In addition, western blotting and qRT-RCR results showed that both CBX4 mRNA and protein levels were downregulated upon miR-195 overexpression. Luciferase reporter assays revealed that CBX4 is a direct target gene of miR-195. Furthermore, overexpression of CBX4 significantly restored the proliferative, invasive and migratory capacities of the HepG2 cells. Finally, in vivo experiments confirmed that high expression of CBX4 in HepG2 cells promoted tumor growth. In conclusion, our study demonstrated that miR-195 acts as a tumor suppressor by directly targeting CBX4 in HCC. This finding suggests a potential novel strategy for therapeutic interventions of this disease.

Preparation and analysis of a new bioorganic metallic material

In this study, a synthetic peptide has been utilized to react with 304 stainless steel aiming to generate a bioorganic stainless steel using a facile technique.

Expression of Girdin in primary hepatocellular carcinoma and its effect on cell proliferation and invasion

Girdin has been proven to play a vital role in the process of proliferation, apoptosis, and invasion in various cancer cells, yet the underlying molecular mechanism in primary hepatocellular carcinoma (HCC) has not yet been clarified. Thereafter, we performed immunohistochemistry to detect the expression of Girdin in 40 primary HCC tissues and 30 matched adjacent tissues using hepatic carcinoma tissue microarray. Our data showed that the positive expression rate of Girdin in hepatocellular carcinoma tissues was 67.5%, higher than that found in adjacent tissues of 16.7% (P < 0.05). It closely correlates to tumor size, T stage, TNM stage and Edmondson-Steiner stage (P < 0.05) of HCC patients. After specific small interfering RNA of Girdin was transfected into HepG2 and Huh7.5.1 cells, the proliferation and invasion ability of tumor cells were significantly inhibited. In summary, we suggest that the oncogenic role of Girdin could provide new molecular target for the treatment of HCC.

Protein engineering of a new recombinant peptide to increase the surface contact angle of stainless steel

Biofouling seriously affects the properties and service life of metal materials.

Mixed endometrial stromal and smooth muscle tumor with heart metastasis: report of a case and review of literature

We presented a case of mixed endometrial stromal sarcoma and smooth muscle cell tumor of the uterus with intravenous metastasis into the right heart. 50 hot mutated key genes of solid tumors were detected by next generation sequencing. The literature about the diagnostic and therapeutic strategies of the disease were reviewed.

First Report of Powdery Mildew Caused by Blumeria graminis on Festuca arundinacea in China

Tall fescue (Festuca arundinacea Schreb), a predominant cool-season perennial grass, is widely used as forage and turf grasses in China. In July 2013, powdery mildew was observed on 10 F. arundinacea lawns (about 0.5 ha in total) in Urumchi, Xinjiang Province, China, with 20 to 30% of the area being infected. Signs of the disease initially appeared as irregular white mycelial colonies on the adaxial surface of infected leaves. As the disease progressed, the colonies covered the whole adaxial surface and white patches appeared on the abaxial surface of infected leaves. Conidiophores were unbranched and cylindrical with swollen bases, measuring 13.3 to 15 × 16.7 to 20 μm, and borne vertically on hyphae. Each conidiophore produced 10 to 18 conidia in a chain. The conidia were oval, one-celled, and colorless, measuring 8.1 to 9.8 × 26 to 29.7 μm. Cleistothecia were black, spherical, and 164.3 to 207.3 μm in diameter, each of which contained 9 to 26 asci. Asci were oblong or ovate, measuring 32.1 to 40 × 85.7 to 96.4 μm. Asci were petiolate, containing eight ascospores. Ascospores were round to oval, colorless, one-celled, measuring 19.1 to 22.5 × 11.7 to 13.6 μm. Based on morphological characteristics of the anamorph and the teleomorph, the fungus was identified as Blumeria graminis (DC.) Speer. Additionally, the internal transcribed spacer (ITS) of 563 bp was amplified from DNA of conidia using ITS1 and ITS4 primers (4). The ITS sequence was deposited in GenBank (Accession No. KF545644). The ITS sequence showed 100% homogeneity with those of B. graminis on Poa pratensis in Swizerland (AB273540) and on P. bulbosa in Iran (AB273551) (1), which further confirmed the identification. Ten 3-week-old healthy plants were inoculated by spraying a spore suspension (1 × 10⁵ conidia ml^-1) made from conidia brushed from infected plants, and 10 plants sprayed with sterile distilled water were served as controls. All the plants were placed in the same growth chamber at 20°C, 80% humidity, and 16-h photoperiod. Twenty days after inoculation, typical signs and symptoms of powdery mildew were observed on all the inoculated plants, whereas no symptoms were observed on the controls. Microscopic and ITS analysis showed that the fungus on the inoculated plants is identical to that on diseased field plants. B. graminis on F. arundinacea has been observed in a few European countries (1), Israel (3), and the United States (2). To our knowledge, this is the first report of powdery mildew caused by B. graminis on F. arundinacea in China, which will increase the difficulty to prevent powdery mildew on grasses including cereals. References: (1) U. Braun. The Powdery Mildews (Erysiphales) of Europe. Gustav Fischer Verlag, Jena-Stuttgart-New York, 1995. (2) F. M. Dugan and G. Newcombe. Pacific Northwest Fungi. 2:1-5, 2007. (3) S. O. Voytyuk et al. Biodiversity of the Powdery Mildew Fungi (Erysiphales, Ascomycota) of Israel Vol. 7. Biodiversity of Cyanoprocaryotes, Algae and Fungi of Israel. Koeltz Scientific Books, 2009. (4) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, 1990.

First Report of Powdery Mildew Caused by Erysiphe betae on Swiss Chard in China

Swiss chard (Beta vulgaris L. subsp. cicla) is a widely planted vegetable in China. From May to June 2013, an outbreak of powdery mildew on Swiss chard cultivar Fangzheng was observed in the commercial fields in Zhoukou city of Henan Province, located in central China. More than 80% of the plants exhibited symptoms of the disease. At the beginning of infection, circular, white, dust-like colonies of powdery mildew occurred mainly on adaxial surfaces of leaves. As the disease progressed, white mycelia covered the foliar parts of plant. No cleistothecia were found on or in collected samples. Upon microscopic evaluation, conidiophores were unbranched with the length of 63 to 126 and width of 7 to 10 μm (n = 50), produced conidia singly, and composed of a cylindrical foot cell followed by one to three short cells. Conidia were colorless, hyaline, ovoid, measured 29 to 40 × 12 to 18 μm (n = 100), lacked fibrosin bodies, and produced germ tubes on the ends of the conidia. The fungus was identified as Erysiphe betae according to the morphological features (1). To verify the identity, the internal transcribed spacer (ITS) region was amplified with the universal primers ITS1 and ITS4 (2) and sequenced. The ITS sequence obtained was assigned as Accession No. KF268348 in GenBank, which showed 100% homogeneity with two ITS sequences of E. betae isolates from UK (DQ164432 and DQ164436). Koch's postulates were conducted by inoculating 15 healthy 5-week-old plants (cv. Fangzheng) with detached infected leaves, which grew in a growth chamber under 22/16°C (day/night), 50% relative humidity, 120 μmol/m²/s light and a 16-h photoperiod. Fifteen non-inoculated plants grew in another growth chamber with the same conditions as control. Symptoms consistent with the infected field plants were observed on the inoculated plants, while no symptoms were found on the control plants. Microscopic observation revealed that the pathogen growing on the inoculated plants was consistent with the morphology of the original fungus. To our knowledge, this is the first report of E. betae infection on Swiss chard in China (3). References: (1) S. Francis. Mol. Plant Pathol. 3:119, 2002. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, CA, 1990. (3) R. Y. Zheng et al. Page 63 in: Flora Fungorum Sinicorum, Vol. 1, Erysiphales. Science Press, Beijing, 1987.

Early experience with the Excluder® iliac branch endoprosthesis

AIM

Dilation of one or both common iliac arteries (CIAs) is a major concern in endovascular aneurysm repair (EVAR). One option for CIA aneurysm repair is hypogastric embolization followed by endograft extension into the external iliac artery. However, hypogastric occlusion does not always go unpunished and it may lead to ischemic complications. Aim of the paper was to evaluate early results with the Gore® Excluder® Iliac Branch Endoprosthesis (IBE) in the treatment of iliac aneurysms associated or not with abdominal aortic aneurysms.

METHODS

Between November 2013 and April 2014, in our Institution 7 Gore IBE were implanted in 5 patients. Technical success, 30-day mortality and complications were investigated.

RESULTS

Technical success and branch patency was 100%. There was no 30-day mortality. In 1 of the 2 bilateral cases an endovascular relining with bare stents was required due to a compression of iliac legs at level of aortic bifurcation.

CONCLUSION

Use of Gore IBE device in the treatment of aorto-iliac disease is feasible and safe. Late results are necessary to evaluate the performance of this endograft in the long term.

MiR-634 sensitizes nasopharyngeal carcinoma cells to paclitaxel and inhibits cell growth both in vitro and in vivo

Resistance to chemotherapy is one of the key causal factors in cancer death and increasing evidence has revealed that microRNAs (miRNAs) are involved in chemoresistance in many kinds of human cancers. Paclitaxel has been used for treatment of advanced nasopharyngeal carcinoma (NPC); however, treatment failure often occurs due to development of acquired paclitaxel resistance. In this study, based on miRNA microarray screening and qRT-PCR validation, we found six differentially expressed miRNAs in our induced paclitaxel-resistant NPC CNE-1/Taxol cells. Furthermore, we clarified the role of miR-634, most significantly downregulated in the paclitaxel-resistant CNE-1/Taxol, in regulating the paclitaxel sensitivity in NPC cells. We restored miR-634 expression in the CNE-1/Taxol cells by lentivirus infection, and found restoration of miR-634 re-sensitized the CNE-1/Taxol cells to paclitaxel in vitro by MTT assay and colony formation assay. In xenograft mouse model, we found that miR-634 inhibited tumor growth and enhanced paclitaxel sensitivity. Thus, our findings provide important information for the development of targeted gene therapy for reversing paclitaxel resistance in NPC.

[Impact of diabetes mellitus on clinicopathological factors and relation with radiation pneumonitis in 332 patients with lung cancer]

OBJECTIVE

To explore the relation between diabetes mellitus and clinicopathological factors and the incidence of radiation pneumonitis in patients with non-small cell lung cancer.

METHODS

The data of 332 patients with non-small cell lung cancer, who were admitted to the Department of Oncology of Third Xiangya Hospital of Central South University between January 2007 and August 2009, were collected retrospectively. The patients were divided into a diabetes mellitus (DM) group (n=45) and a non-diabetes mellitus (NDM) group (n=287). The clinicopathological factors were compared between the two groups. The patients who received radiotherapy were further divided into a diabetes mellitus (DMR) group (n=33) and a non-diabetes mellitus group (NDMR) group(n=287), and the incidence of radiation pneumonitis was compared.

RESULTS

A total of 45 patients (13.55%)developed diabetes mellitus. There was significant difference in the body-weight, age and hypertension (P<0.05), while no significant difference in the pathologic factors, such as tumor pathological type, degree of differentiation, and classification of malignant tumors (TNM) stage between the two groups(P>0.05). No significant difference in the irradiation area was found between the DM group and the NDM group(P>0.05). The incidence of radiation pneumonitis in the DMR group was 42.42%(14 out of 33), while 21.31%(39 out of 183) in the NDMR group, with significant difference in the incidence of radiation pneumonitis between the DMR group and the NDMR group(P<0.05). The risk value in the DMR group was 2.721 folds (95%CI, 1.253-5.910) that in the NDMR group in patients with non-small cell lung cancer companied with diabetes mellitus.

CONCLUSION

Diabetes mellitus is the risk factor of radiation pneumonitis for patients with nonsmall cell lung cancer who receive radiotherapy.

MiR-20a inhibits cutaneous squamous cell carcinoma metastasis and proliferation by directly targeting LIMK1

BACKGROUND

MicroRNA-20a (miR-20a) plays a key role in tumorigenesis and progression. But its function is reverse in different kinds of malignant tumor, and its role and mechanism in cutaneous squamous cell carcinoma (CSCC) remains unclear.

OBJECT

To determine the miR-20a's roles in CSCC and confirm whether LIMK1 is a direct target gene of miR-20a.

METHODS

First miR-20a and LIMK1 expression levels were detected in six pairs of CSCC tissues and corresponding normal skin by qRT-PCR. Then MTT assays and colony formation assays were performed to evaluate the impact of miR-20a on cell proliferation. In addition, scratch migration assays and transwell invasion assays were performed to check miR-20a's effect on cell metastasis. Since LIMK1 (LIM kinase-1) was predicted as a target gene of miR-20a, the changes of LIMK1 protein and mRNA were measured by western blot and qRT-RCR methods after miR-20a overexpression. Moreover the dual reporter gene assay was performed to confirm whether LIMK1 is a direct target gene of miR-20a. Finally LIMK1 mRNA and miR-20a in other 30 cases of CSCC pathological specimens were determined and a correlation analysis was evaluated.

RESULTS

The miR-20a significantly low-expressed in CSCC tissues compared with that in matched normal tissues while LIMK1 has a relative higher expression. MiR-20a inhibited A431 and SCL-1 proliferation and metastasis. Both of LIMK1 protein and mRNA levels were downregulated after miR-20a overexpression. The dual reporter gene assays revealed that LIMK1 is a direct target gene of miR-20a. Furthermore, qRT-PCR results of LIMK1 mRNA and miR-20a in 30 cases of CSCC pathological specimens showed miR-20a is inversely correlated with LIMK1 expression.

CONCLUSION

Our study demonstrated that miR-20a is involved in the tumor inhibition of CSCC by directly targeting LIMK1 gene. This finding provides potential novel strategies for therapeutic interventions of CSCC.

Talen-mediated girdin knockout downregulates cell proliferation, migration and invasion in human esophageal carcinoma ECA109 cells

Girdin is an actin-binding Akt substrate that is involved in the regulation of cell migration. Accumulating evidence has revealed that girdin has regulatory effects on invasion and metastasis in several types of cancer. However, the role of girdin in esophageal squamous cell carcinomas (ESCCs) is yet to be investigated. In the present study, tissue microarray data revealed that among 95 cases of ESCC, 27 cases (28.7%) exhibited a low expression of girdin, while 67 cases (71.3%) had an enhanced expression of girdin. However, among 78 cases of adjacent tissues, 64 cases (82.1%) did not express girdin and 14 cases (17.9%) exhibited a low expression of girdin. Furthermore, the expression of girdin was significantly associated with the tumor stage, lymph node metastasis stage, and tumor, lymph node and metastasis stage. Of note, the mean survival time of girdin-positive cases was only 30.62±2.99 months, while it was 53.37±5.02 months in girdin-negative cases, indicating that girdin protein expression is an independent prognostic factor of poor survival. Talen-mediated girdin knockout (KO) significantly suppressed cellular proliferation, migration and invasion in ESCC ECA109 cells. In conclusion, the present study suggested that girdin protein expression was significantly correlated with cancer progression and poor prognosis in ESCCs, and that girdin had a positive role in the regulation of cell proliferation, migration and invasion in ESCC cells. Therefore, girdin may be a potential candidate for the development of novel prognostic tools and therapeutic strategies for ESCCs.

Additive effects of antiresorptive agents and exercise on lumbar spine bone mineral density in adults with low bone mass: a meta-analysis

INTRODUCTION

Exercise has been recommended to increase bone mass and prevent osteoporosis. While current treatment of osteoporosis mainly involves the use of antiresorptive agents, it is unclear whether there are any additive effects in improving bone mass when antiresorptive agents and exercise are jointly used.

METHODS

A structured and comprehensive search of databases was undertaken along with hand searching of key journals and reference lists. The combined interventions of antiresorptive agents and exercise were examined for their additive effects on lumbar spine bone mineral density (BMD) among adults with low bone mass. Trial quality was assessed using the Jadad quality score. Study outcomes for analysis, absolute change (grams per square centimeter) or relative change (in percent) in BMD, at the lumbar spine were compared by calculating standardized mean difference (SMD) using fixed and random effect models.

RESULTS

Seven randomized controlled trials (RCT) met the predetermined inclusion criteria. The increase in lumbar spine BMD of the combined-intervention group was significantly greater than that of the antiresorptive agent-alone group (fixed effect model: SMD = 0.55; 95% confidence interval (CI) = 0.36, 0.75; overall effect Z-value = 5.51; p < 0.00001). Subgroup analyses also showed consistent results. Methodological quality of most included studies was scored 3 by the Jadad criterion, and publication bias was slight according to funnel plots.

CONCLUSION

It was found that combining antiresorptive agents with exercise had additive effects on improving lumbar spine bone mass gains in adults with low bone mass. To verify the additive effects further, more RCTs with longer duration and larger sample sizes are needed.

Current results of total endovascular repair of thoracoabdominal aortic aneurysms

Minimally invasive surgical solutions for patients with extensive aortic disease are eagerly awaited, since open repair is often associated with high rates of morbidity and mortality. In the last decade, the development of fenestrated and branched aortic endografts has offered a therapeutic option to patients deemed unsuitable for major surgery. Preliminary studies showed promising early results, while mid- and long- term data are scarce. The aim of this paper was to review current results of total endovascular repair of thoracoabdominal aortic aneurysms (TAAA) with a single model of endograft in the published literature. A literature search was conducted, and our two-center experience with fenestrated and branched endografts in the treatment of TAAA, with the Cook Zenith endograft, is presented. Early results show perioperative mortality rates ranging from 0% to 21%, spinal cord ischemia from 0% to 33.3%. At a mean follow up ranging from 9 to 19 months, reinterventions are needed in 3.3% to 25% of the cases, with a mid term visceral branch patency of 90% to 100%. Current experiences with total endovascular TAAA repair show promising results, in selected centers with large experience in complex aortic endografting. With increasing follow- up times, need for reintervention is growing, while aneurysm-related deaths remain rare. Long-term results are still lacking, but these encouraging data and further technological developments will support wider adoption of the technique.

Effects of ischemic preconditioning in the late phase on homing of endothelial progenitor cells in renal ischemia/reperfusion injury

OBJECTIVE

The aim of this study was to determine whether the mobilization and recruitment of endothelial progenitor cells (EPCs) contribute to the protection of kidneys from ischemia/reperfusion (I/R) injury after ischemic preconditioning (IPC) during the late phase.

METHODS

Seventy-five male Sprague-Dawley rats were divided into the following groups: sham-operated (group A; n = 25), ischemia/reperfusion hosts that underwent 45 minutes of left renal artery ischemia (group B; n = 25), and ischemic preconditioning-treated group (group C; n = 25). Group C underwent 3 cycles of 5 minutes of occlusion and 5 minutes of reperfusion followed by 24 hours of reperfusion before the following 45 minutes of occlusion. Serum samples were collected and renal tissues harvested for histological examination terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, immunohistochemical staining, and Western blot analysis to determine the expression levels of CD34, VEGFR-2 (Vascular Endothelial Growth Factor Receptor 2)/flk-1, vascular endothelial growth factor (VEGF), and stromal cell-derived factor-1α (SDF-1α).

RESULTS

Compared with group B, the levels of blood urea nitrogen (BUN), serum creatinine (Scr) and acute tubulointerstitial injury at 24 hours after operation were significantly reduced in group C. At 72 hours, tubular epithelial cell apoptosis was also decreased (17.6 ± 4.45 vs 63.8 ± 6.10; P < .01). CD34+ and flk-1+ cells that mostly accumulated in the medullopapillary parenchyma were significantly increased at 72 hours (P < .05). Expression levels of VEGF and SDF-1α were also significantly higher in group C (P < .05).

CONCLUSION

The present work suggested that IPC protected kidneys from IR injury in the later phase through enhanced mobilization and recruitment of EPCs. VEGF and SDF-1α may play important roles in this protective effect.