Berberine alleviates the cerebrovascular contractility in streptozotocin-induced diabetic rats through modulation of intracellular Ca²âº handling in smooth muscle cells.

BACKGROUND: Vascular dysfunction is a distinctive phenotype in diabetes mellitus. Current treatments mostly focus on the tight glycemic control and few of these treatments have been designed to directly recover the vascular dysfunction in diabetes. As a classical natural medicine, berberine has been explored as a possible therapy for DM. In addition, it is reported that berberine has an extra-protective effect in diabetic vascular dysfunction. However, little is known whether the berberine treatment could ameliorate the smooth muscle contractility independent of a functional endothelium under hyperglycemia. Furthermore, it remains unknown whether berberine affects the arterial contractility by regulating the intracellular Ca(2+) handling in vascular smooth cells (VSMCs) under hyperglycemia. METHODS: Sprague-Dawley rats were used to establish the diabetic model with a high-fat diet plus injections of streptozotocin (STZ). Berberine (50, 100, and 200 mg/kg/day) were intragastrically administered to control and diabetic rats for 8 weeks since the injection of STZ. The intracellular Ca(2+) handling of isolated cerebral VSMCs was investigated by recording the whole-cell L-type Ca(2+) channel (CaL) currents, assessing the protein expressions of CaL channel, and measuring the intracellular Ca(2+) in response to caffeine. Our results showed that chronic administration of 100 mg/kg/day berberine not only reduced glucose levels, but also inhibited the augmented contractile function of cerebral artery to KCl and 5-hydroxytryptamine (5-HT) in diabetic rats. Furthermore, chronic administration of 100 mg/kg/day berberine significantly inhibited the CaL channel current densities, reduced the α1C-subunit expressions of CaL channel, decreased the resting intracellular Ca(2+) ([Ca(2+)]i) level, and suppressed the Ca(2+) releases from RyRs in cerebral VSMCs isolated from diabetic rats. Correspondingly, acute application of 10 µM berberine could directly inhibit the hyperglycemia-induced CaL currents and suppress the hyperglycemia-induced Ca(2+) releases from RyRs in cerebral VSMCs isolated from normal control rats. CONCLUSIONS: Our study indicated that berberine alleviated the cerebral arterial contractility in the rat model of streptozotocin-induced diabetes via regulating the intracellular Ca(2+) handling of smooth muscle cells.

Saikosaponin-D enhances radiosensitivity of hepatoma cells under hypoxic conditions by inhibiting hypoxia-inducible factor-1α.

BACKGROUND: Our previous study revealed that the combination of Saikosaponin-d ( SSd) and radiation is more effective in the treatment of liver cancer than the application of either of these monotherapeutic methods. However, the molecular mechanisms of the radiosensitizing effect of SSd on liver cancer remained ill defined. METHODS: Cells were treated with different interventions; afterward, cell viability, apoptosis, and cell survival of SMMC-7721 and HepG2 hepatoma cells were examined. Xenograft tumor models were established by subcutaneously injecting SMMC-7721 cells. The molecular mechanism was assessed by western blot. RESULTS: SSd dose-dependently increased radiosensitivity of hepatoma cells under hypoxic condition. The growth inhibitory effect of the combined treatment was correlated with cell apoptosis. Further mechanistic analysis indicated that SSd induced the upregulation of p53 and Bax as well as the downregulation of Bcl-2 by attenuating HIF-1α expression under hypoxic condition. These effects were enhanced when the HIF-1α inhibitor PX-478 was introduced. In vivo data also presented a more significant suppression of tumor xenograft growth from the combined therapy than from either of the monotherapeutic methods. CONCLUSIONS: Our study provides evidence for a radiosensitizing effect of SSd on hepatoma cells under hypoxic conditions by inhibiting HIF-1α expression. Thus, SSd can be used as a potential sensitizer in hepatoma radiotherapy. © 2014 S. Karger AG, Basel.

Functional promoter -765 G > C variant in COX-2 gene is associated with the susceptibility of breast cancer in Chinese Han women.

BACKGROUND: Cyclooxygenase (COX) is a rate-limiting enzyme in prostaglandins synthesis which exists in two isoforms, COX-1 and COX-2. Over-expression of COX-2 was considered to increase the proliferation and enhance the invasiveness of breast cancer cells. It was suggested that genetic variations in COX-2 could influence its expression. Herein, the present study was aimed to investigate the associations between two mostly studied functional polymorphisms (-765 G > C and 8473 C > T) in COX-2 and breast cancer risk in Chinese Han women. METHODS: In the hospital-based case-control study, 465 breast cancer patients and 799 cancer-free controls were genotyped for the COX-2 -765 G > C and 8473 C > T polymorphisms using TaqMan assay. We estimated odds ratios (ORs) and 95% confidence intervals (95% CIs) using the logistic regression. RESULTS: Compared with the wild genotype of -765 G > C, we found a statistically significant increased risk of breast cancer associated with the variant genotypes [GC/CC vs. GG: OR = 1.56, 95% CI = 1.11-2.21]. In the stratified analysis, the increased risk was more predominant among the subgroups of younger subjects (OR = 1.61, 95% CI = 1.00-2.61). Furthermore, the variant genotypes were associated with large tumor size (OR = 3.01, 95% CI = 1.47-6.12). No significant association was observed for the 8473 C > T polymorphism. CONCLUSIONS: Our results suggest that the functional -765 G > C polymorphism in the promoter of COX-2 may influence the susceptibility and progression of breast cancer in the Chinese Han population.

[Preparation and investigation of MRI-traceable Eudragit-E liquid embolic agent].

OBJECTIVE: To develop and investigate the properties of MRI-traceable Eudragit-E liquid embolic agent (MR-E). METHODS: Polyethylene glycol-modified superparamagnetic iron oxides (PEG-SPIO) was synthesized by chemical co-precipitation method. MR-E was prepared by mixing PEG-SPIO and Eudragit-E liquid embolic agent homogeneously. An in vitro MR phantom study was carried out to measure MR traceability of MR-E and to determine the concentration of PEG-SPIO for further studies. The microcatheter deliverability and sol-gel transition process of MR-E were investigated. MR-E was injected into the kidney of a Japanese white big ear rabbit via an angiographic microcatheter, and detected by MRI. RESULTS: A PEG-SPIO concentration of 2 g/L was considered to be suitable for further studies. MR-E was injected through the microcatheter without any difficulty. MR-E instantly solidified on release into saline. Then 0.2 mL of MR-E effectively embolized distal renal arteries, and MR-E could be detected by MRI in the embolized kidney. CONCLUSION: MR-E seems to be a promising MRI-traceable liquid embolic agent.

[Preparation and property study of doxorubicin loaded microspheres].

OBJECTIVE: To prepare doxorubicin-loaded polyvinylalcohol-acrylic acid (PVA-AA) microspheres and evaluate properties of this chemoembolic agent. METHODS: PVA-AA microspheres were synthesized by inverse suspension polymerization method and then verified by infrared spectroscopy. drug loading (DL) and entrapment efficiency (EE%) were measured after doxorubicinwas loaded on PVA-AA microspheres. Their morphology and elasticity were investigated by optical microscope, environmental scanning electron microscope and texture analyzer, respectively. T-cell apparatus was used to evaluate the in vitro release behavior of doxorubicin-loaded microspheres.The external carotid of the rabbit was chosen as an embolization site to evaluate the in vivo embolic property of the microspheres. RESULTS: PVA-AA microspheres, which were transparent spheres,turned into red spheres after doxorubicin loading. DL of the microspheres was (20.56 ± 0.69)g/L and (23.25 ± 0.27) g/L,and EE% was 82.22% ± 2.76% and 93.00% ± 1.06% within 20 min and 6 h, respectively. The in vitro release results showed a significantly delayed release of the drug for 10.32% ± 0.47% after 24 h. The Young's modulus was (178.30 ± 12.33) kPa and (213.29 ± 15.61) kPa for blank microspheres and doxorubicin-loaded microspheres, respectively. Both blank microspheres and doxorubicin-loaded microspheres exhibited good elasticity. In vivo embolization showed that 0.3 mL of microspheres could produce distal embolic efficiency. CONCLUSION: The doxorubicin-loaded microspheres are expected to be a promising new chemoembolic agent.

Possible role of mast cells and neuropeptides in the recovery process of dextran sulfate sodium-induced colitis in rats.

OBJECTIVE: To clarify the role of mast cells and neuropeptides substance P (SP), somatostatin (SS), and vasoactive intestinal peptide (VIP) in dextran sulfate sodium (DSS)-induced colitis in rats. METHODS: Experimental colitis was induced in Sprague-Dawley rats (180-200 g, n=20) by oral ingestion of 4% (w/v) DSS in drinking water for 7 days. Control rats (n=5) drank water and were sacrificed on day 0. Mast cell number, histamine levels in whole blood and tissue, tissue levels of SP, SS and, VIP in the distal colon of the rats were measured on day 8, day 13, and day 18 of experimentation. RESULTS: Oral administration of 4% DSS solution for 7 days resulted in surface epithelial loss and crypt loss in the distal colon. Mast cell count increased on day 8 (1.75±1.09/mm vs. 0.38±0.24/mm, P<0.05) and day 13 (1.55±1.01/mm vs. 0.38±0.24/mm, P<0.05) after DSS treatment. Whole blood histamine levels were increased on day 8 (266.93±35.62 ng/mL vs. 76.87±32.28 ng/mL, P<0.01) and gradually decreased by day 13 and day 18 after DSS treatment. Histamine levels in the distal colon were decreased on day 8 (1.77±0.65 ng/mg vs. 3.06±0.87 ng/mg, P<0.05) and recovered to control levels by day 13 after DSS treatment. SP level in the distal colon gradually increased and were raised significantly by day 13 (8777.14±3056.14 pg/mL vs. 4739.66±3299.81 pg/mL, P<0.05) after DSS treatment. SS and VIP levels in the distal colon were not changed. CONCLUSIONS: Mast cell degranulation followed by histamine release may play an important role in the pathogenesis of colitis induced by DSS. SP may be a significant substance in the progression of inflammation and the recovery process of DSS-induced colitis.

Antitumor activity of the selective cyclooxygenase-2 inhibitor, celecoxib, on breast cancer in Vitro and in Vivo.

BACKGROUND: Cyclooxygenase-2(COX-2) promotes carcinogenesis, tumor proliferation, angiogenesis, prevention of apoptosis, and immunosuppression. Meanwhile, COX-2 over-expression has been associated with tumor behavior and prognosis in several cancers. This study investigated the antitumor effects of the selective COX-2 inhibitor, Celecoxib, on breast cancer in vitro and in vivo. METHODS: Human breast cancer MCF-7 and MDA-MB-231 cells were cultured with different concentration (10, 20, 40 µmol/L) of celecoxib after 0-96 hours in vitro. MTT assay was used to determine the growth inhibition of breast cancer cells in vitro. The expression of COX-2 on mRNA was measured by real-time quantitive PCR analysis. Flow cytometry was performed to analyze the cell cycle of MCF-7 cells. Levels of PGE2 were measured by ELISA method. The in vivo therapeutic effects of celecoxib were determined using rat breast cancer chemically induced by 7,12-dimethylben anthracene (DMBA). RESULTS: The inhibition of proliferation of both MCF-7 and MDA-MB-231 cells in vitro by celecoxib was observerd in time and dose dependent manner. Celecoxib effectively down-regulated the expression of COX-2. The cell cycle was arrested at G0/G1, and rate of cells in S phase was obviously decreased. Levels of PGE2 were inhibited by Celecoxib. The tumor incidence rate of the celecoxib group was lower than that of the control group. In addition, the tumor latency period of the celecoxib group was longer than that of the control group. CONCLUSIONS: Celecoxib inhibited the proliferation of breast cancer cell lines in vitro, and prevented the occurrence of rat breast cancer chemically induced by DMBA. Therefore, celecoxib exhibits an antitumor activity and seems to be effective in anti-tumor therapy.

In vitro and in vivo antitumor activity of Scutellaria barbate extract on murine liver cancer.

In the present study, we investigated the in vitro and in vivo antitumor effects of crude extract of Scutellaria Barbate (CE-SB) on mouse hepatoma H22 cells. The MTT assay was used to determine the growth inhibition of H22 cells in vitro. The in vivo therapeutic effects of CE-SB were determined using H22 tumor bearing mice. Besides, the body weight, tumor weight, thymus index and spleen index of H22 bearing mice were also measured. The tumor inhibitory rate (IR) was calculated according to the mean weight of tumor (MWT). The phagocytotic function of macrophages was examined by observing peritoneal macrophages phagocytize chicken RBC. The results showed that CE-SB could inhibit the growth of hepatoma H22 Cells in vitro and in vivo. Furthermore, CE-SB could improve immune function of H22 tumor bearing mice. Together these results indicate that CE-SB has antitumor activity and seems to be safe and effective for the use of anti-tumor therapy.

Comparison of Clinical and Radiological Outcomes Between Upper Fibular Curvature and Non-Curvature with Medial Knee Osteoarthritis Following Proximal Fibular Osteotomy: A Retrospective Cohort Study with Minimum 2-Year Follow-up.

OBJECTIVE: To evaluate and compare the clinical and radiographic outcomes of proximal fibular osteotomy (PFO) in treating medial knee osteoarthritis (KOA) patients with upper fibular curvature and non-curvature. METHODS: A retrospective cohort study was performed. From January 2016 to January 2017, a total of 51 patients (nine males and 42 females) at a mean age of 63.7 years (range 48-79 years) with medial KOA who underwent PFO procedure at the Third Hospital of Hebei Medical University were included in the study. The patients were divided into the two groups, namely curvature group (28 patients, six males and 22 females, aged 62.6 ± 7.7 years) and non-curvature group (23 patients, three males and 20 females, aged 64.5 ± 7.6 years). Perioperative parameters and Kellgren-Lawrence classification were recorded and analyzed in the two groups, respectively. All patients were followed up at 1, 3, 6, and 12 months at the first year of post-operation, and then every 6 months from the second year of post-operation. A telephone survey with standard questionnaire survey, including Visual Analog Scale (VAS) score and Hospital for Special Surgery (HSS) scoring system, was used to evaluate postoperative clinical outcomes. Radiological results were assessed using the femorotibial angle (FTA), hip-knee-ankle angle (HKA), and settlement value of medial tibial platform (MTP) in the two groups. RESULTS: The average follow-up periods of the curvature group and the non-curvature group were 34.8 ± 6.1 and 33.9 ± 5.4 months, respectively. There were no significant differences between the two groups of demographic data in terms of number of patients, age, body mass index (BMI), gender, KOA side, and Kellgren-Lawrence classification (P > 0.05). The VAS scores of the curvature group and non-curvature group were (3.53 ± 1.62 vs 3.68 ± 1.43 at 1 month, 3.46 ± 0.79 vs 3.57 ± 0.66 at 3 months, and 2.43 ± 0.88 vs 2.83 ± 0.94 at 6 months, both P > 0.05), while significant differences were found from 12 months post-operation (1.54 ± 0.72 vs 2.03 ± 0.85 at 12 months, and 1.04 ± 0.69 vs 1.74 ± 0.75 at 24 months, both P < 0.05). The HSS scores of the curvature group and non-curvature group were (79.67 ± 5.14 vs 78.25 ± 6.37 at 1 month, 84.65 ± 3.76 vs 83.18 ± 3.64 at 3 months, and 86.27 ± 3.13 vs 85.49 ± 3.25 at 6 months, both P > 0.05), while significant differences were found from 12 months post-operation (90.64 ± 4.32 vs 87.71 ± 5.63 at 12 months, and 92.93 ± 2.07 vs 90.06 ± 2.08 at 24 months, both P < 0.05). In addition, the FTA and settlement value of the curvature group were lower than the non-curvature group (177.18 ± 1.52 vs 178.35 ± 1.86, and 5.29 ± 1.74 vs 6.49 ± 2.09, both P < 0.05) while the HKA were higher than the non-curvature group (175.32 ± 2.34 vs 173.83 ± 2.64, P < 0.05) at the final follow-up. CONCLUSIONS: Medial KOA patients with upper fibular curvature is an optimal surgical indication for PFO surgery, with the advantages of pain relief, better functional recovery, and alignment correction.

MicroRNA-552 deficiency mediates 5-fluorouracil resistance by targeting SMAD2 signaling in DNA-mismatch-repair-deficient colorectal cancer.

OBJECTIVE: Although DNA-mismatch-repair-deficient (dMMR) status and aberrant expression of miRNAs are both critically implicated in the pathogenesis of resistance to 5-fluorouracil (5-FU) in colorectal cancer (CRC), whether these two factors regulate tumor response to 5-FU in a coordinated manner remains unknown. This study is designed to elucidate whether changes in miR-552 expression levels correlate to 5-FU-based chemoresistance in CRC, and to further identify the putative targets of miR-552 using multiple approaches. METHODS: miR-552 expression was assessed in 5-FU-resistant CRC tissues and cells using real-time PCR. Effects of miR-552 dysregulation on 5-FU resistance in CRC cells were determined by measuring cell viability, apoptosis and in vivo oncogenic capacity. Finally, we studied the posttranscriptional regulation of SMAD2 by miR-552 using multiple approaches including luciferase reporter assay, site-directed mutagenesis and transient/stable transfection, at molecular and functional levels. RESULTS: Expression of miR-552 was significantly downregulated in 5-FU-resistant CRC tissues and cells, and this downregulation, regulated by dMMR, was associated with poor postchemotherapy prognosis. Functionally, forced expression of miR-552 exhibited a proapoptotic effect and attenuated 5-FU resistance, whereas inhibition of miR-552 expression potentiated 5-FU resistance in CRC cells. Mechanically, miR-552 directly targeted the 3'-UTR of SMAD2, and stable ablation of SMAD2 neutralized the promoting effects of miR-552 deficiency-induced 5-FU resistance. CONCLUSIONS: Overall, our findings have revealed a critical role of miR-552/SMAD2 cascade in modulating cellular response to 5-FU chemotherapy. miR-552 may act as an efficient mechanistic link synchronizing dMMR and 5-FU resistance in CRC.

MRI Detectable Polymer Microspheres Embedded With Magnetic Ferrite Nanoclusters For Embolization: In Vitro And In Vivo Evaluation.

OBJECTIVE: The objective of this study was to develop magnetic embolic microspheres that could be visualized by clinical magnetic resonance imaging (MRI) scanners aiming to improve the efficiency and safety of embolotherapy. METHODS AND DISCUSSION: Magnetic ferrite nanoclusters (FNs) were synthesized with microwave-assisted solvothermal method, and their morphology, particle size, crystalline structure, magnetic properties as well as T2 relaxivity were characterized to confirm the feasibility of FNs as an MRI probe. Magnetic polymer microspheres (FNMs) were then produced by inverse suspension polymerization with FNs embedded inside. The physicochemical and mechanical properties (including morphology, particle size, infrared spectra, elasticity, etc.) of FNMs were investigated, and the magnetic properties and MRI detectable properties of FNMs were also assayed by vibrating sample magnetometer and MRI scanners. Favorable biocompatibility and long-term MRI detectability of FNMs were then studied in mice by subcutaneous injection. FNMs were further used to embolize rabbits' kidneys to evaluate the embolic property and detectability by MRI. CONCLUSION: FNMs could serve as a promising MRI-visualized embolic material for embolotherapy in the future.

Scutellaria barbate extract induces apoptosis of hepatoma H22 cells via the mitochondrial pathway involving caspase-3.

AIM: To study the growth inhibitory and apoptotic effects of Scutellaria barbata D.Don (S. barbata) and to determine the underlying mechanism of its antitumor activity in mouse liver cancer cell line H22. METHODS: Proliferation of H22 cells was examined by MTT assay. Cellular morphology of PC-2 cells was observed under fluorescence microscope and transmission electron microscope (EM). Mitochondrial transmembrane potential was determined under laser scanning confocal microscope (LSCM) with rhodamine 123 staining. Flow cytometry was performed to analyze the cell cycle of H22 cells with propidium iodide staining. Protein level of cytochrome C and caspase-3 was measured by semi-quantitive RT-PCR and Western blot analysis. Activity of caspase-3 enzyme was measured by spectrofluorometry. RESULTS: MTT assay showed that extracts from S. barbata (ESB) could inhibit the proliferation of H22 cells in a time-dependent manner. Among the various phases of cell cycle, the percentage of cells in S phase was significantly decreased, while the percentage of cells in G(1) phase was increased. Flow cytometry assay also showed that ESB had a positive effect on apoptosis. Typical apoptotic morphologies such as condensation and fragmentation of nuclei and blebbing membrane of apoptotic cells could be observed under transmission electron microscope and fluorescence microscope. To further investige the molecular mechanism behind ESB-induced apoptosis, ESB-treated cells rapidly lost their mitochondrial transmembrane potential, released mitochondrial cytochrome C into cytosol, and induced caspase-3 activity in a dose-dependent manner. CONCLUSION: ESB can effectively inhibit the proliferation and induce apoptosis of H22 cells involving loss of mitochondrial transmembrane potential, release of cytochrome C, and activation of caspase-3.

[Anti-proliferative and apoptosis-inducing activity of Scutellaria barbate containing serum on mouse's hepatoma H22 cells].

OBJECTIVE: To investigate the effects of Scutellaria barbate extract (ESB) on suppressing proliferation and inducing apoptosis of mouse hepatoma H22 cells. METHODS: H22 cells cultured in vitro were divided into 5 groups: blank control group, ESB in high, medium, low dose groups and 5-Fu group. H22 cells were cultured in media with serum containing different concentrations of ESB and blank serum. The proliferation of H22 cells was determined by microculture tetrazolium (MTT) assay. Fluorescence microscopy was utilized to observe the apoptosis of H22 cells by staining with Hoechst 33258. The cell cycle and apoptosis were analyzed by flow cytometry (FCM). RESULTS: The inhibition of serum containing ESB on the proliferation of H22 cells in vitro was observerd in a dose and time dependent manner. The typical morphological changes of apoptosis were observed after incubation with ESB-containing serum in high dose for 48 hours. Among the various phases of cell cycle, the percentage of cells in S phase decreased significantly, while the percentage of cells in G1 phase increased. Drug-containing serum showed positive effect on cell apoptosis. The apoptosis rate of blank control group, ESB in low, medium, high dose groups and 5-Fu group were 0.51%, 1.07%, 3.15%, 7.83%, 11.26%, respectively. CONCLUSION: ESB containing serum can inhibit proliferation and induce apoptosis of H22 cells in vitro.

[Effects of Scutellaria Barbata drug-containing serum on apoptosis and mitochondrial transmembrane potential of hepatoma H22 cells].

OBJECTIVE: To investigate the effects of serum containing Scutellaria Barbata extract (ESB) on apoptosis rate and mitochondrial transmembrane potential (MTP) of liver cancer cell line H22 from mice in vitro. METHODS: H22 cells were cultured in vitro and divided into 5 groups: blank control group, low-dose ESB group, medium-dose ESB group, high-dose ESB group and fluorouracil (5-Fu) group. Methyl thiazolyl tetrazolium assay was utilized to determine the proliferation rates of H22 cells. Cellular morphology was observed under a transmission electron microscope (EM). The rhodamine 123 was used as a fluorescence probe to label the H22 cells, and the fluorescence intensities were observed with a laser scanning confocal microscope. The fluorescence intensity of H22 cells indicated the MTP of H22 cells. RESULTS: The inhibition of serum containing ESB on the proliferation of H22 cells in vitro was observed in a time-dependent manner. The typical morphological changes of apoptosis were observed after incubation with ESB-containing serum in high dose for 48h. The apoptosis rates of blank control group, 5-Fu group, low-dose ESB group, medium-dose ESB group and high-dose ESB group were (0.51+/-0.32)%, (11.26+/-2.97)%, (1.07+/-0.46)%, (3.15+/-1.12)%, (7.83+/-2.25)% respectively. ESB could reduce the MTP of H22 cells from mice as compared with the untreated group. The MTPs of the blank control group, 5-Fu group, and low-, medium- and high-dose ESB groups were (245.45+/-67.37), (127.42+/-41.35), (213.68+/-65.52), (186.34+/-56.37) and (142.65+/-39.44) respectively, which were negatively correlated with the apoptosis rates. CONCLUSION: ESB-containing serum effectively induces apoptosis, which may be related to the decrease of MTP in H22 cells.

Knockdown of Tripartite Motif-Containing Protein 37 (TRIM37) Inhibits the Proliferation and Tumorigenesis in Colorectal Cancer Cells.

Tripartite motif-containing protein 37 (TRIM37), a new member of the RING-B-box-coiled-coil (RBCC) subfamily of zinc finger proteins, was found to be involved in the development and progression of several cancers. However, the expression pattern and biological functions of TRIM37 in colorectal cancer (CRC) remain unknown. Therefore, in the present study, we examined the expression pattern of TRIM37 in CRC and investigated the function of TRIM37 in the progression of CRC. Our results showed that TRIM37 expression was upregulated in CRC cell lines. Knockdown of TRIM37 inhibited CRC cell proliferation and tumor growth in vivo. Furthermore, knockdown of TRIM37 inhibited the migration and invasion in CRC cells. Last, knockdown of TRIM37 inhibited the protein level expression of ß-catenin, cyclin D1, and c-Myc in CRC cells. In conclusion, these results demonstrate that TRIM37 may play an important role in the proliferation, invasion, and tumorigenesis of CRC cells. Thus, TRIM37 may be a potential therapeutic target for the treatment of CRC.

Poly(acrylic acid) microspheres loaded with superparamagnetic iron oxide nanoparticles for transcatheter arterial embolization and MRI detectability: In vitro and in vivo evaluation.

To develop embolic microspheres with MRI detectability, superparamagnetic iron oxide nanoparticles (SPIONs) were synthesized and mixed with monomer of acrylic acid to prepare SPIONs-loaded polymerized microspheres (SPMs) by inverse suspension polymerization method. The SPMs were evaluated for the ability of embolization by investigating the morphology, particle size, elasticity and renal arterial embolization to rabbits. Meanwhile, the loading of SPIONs was verified by optical microscope, transmission electron microscope, Fourier transform infrared spectrum, vibrating sample magnetometer, X-ray diffraction and X-ray photoelectron spectroscopy, and the content of SPIONs in SPMs was measured quantitatively. Furthermore, the MRI detectability of SPMs was testified in gel phantom, mice and rabbits respectively by a clinical 3.0T MRI scanner. The results revealed the SPMs were potential MRI detectable embolic microspheres for improving the effectiveness and safety of embolotherapy in the future.

Genetic polymorphisms (rs10636 and rs28366003) in metallothionein 2A increase breast cancer risk in Chinese Han population.

Genetic polymorphisms of MT2A are frequently observed in many different cancers. We performed this case-control study, including 459 breast cancer (BC) patients and 549 healthy controls from Northwest China, to evaluate the associations between two common MT2A polymorphisms (rs10636 and rs28366003) and BC risk. The MT2A polymorphisms were genotyped via Sequenom MassARRAY. The individuals with the rs28366003 A/G, A/G-G/G genotypes underwent a higher risk of BC (P<0.0001). And, the minor allele G of rs28366003 was related to an increased BC risk (P<0.0001). We also found a significantly increased BC risk with rs10636 polymorphism among homozygote and recessive models (P<0.05). Further subgroup analysis by clinical characteristics of BC patients showed that Scarff, Bloom and Richardson tumor grade (SBR) 1-2 have a higher expression of the minor allele of these two MT2A loci than SBR 3. Our results indicated that the rs10636 and rs28366003 polymorphisms in MT2A increased BC risk in Northwest Chinese Han population.

Down-regulation of survivin expression by small interfering RNA induces pancreatic cancer cell apoptosis and enhances its radiosensitivity.

AIM: To investigate the inhibitory effect of small interfering RNA (siRNA) on the expression of survivin in pancreatic cancer cell line PC-2 and the role of siRNA in inducing PC-2 cell apoptosis and enhancing its radiosensitivity. METHODS: A siRNA plasmid expression vector against survivin was constructed and transfected into PC-2 cells with Lipofectamine 2000. The down regulation of survivin expression was detected by semi-quantitative RT-PCR and immunohistochemical SP method and the role of siRNA in inducing PC-2 cell apoptosis and enhancing its radiosensitivity was detected by flow cytometry. RESULTS: The sequence-specific siRNA efficiently and specifically down-regulated the expression of survivin at both mRNA and protein levels. The expression inhibition ratio was 81.25% at mRNA level detected by semi-quantitative RT-PCR and 74.24% at protein level detected by immunohistochemical method. Forty-eight hours after transfection,apoptosis was induced in 7.03% cells by siRNA and in 14.58% cells by siRNA combined with radiation. CONCLUSION: The siRNA plasmid expression vector against survivin can inhibit the expression of survivin in PC-2 cells efficiently and specifically. Inhibiting the expression of survivin can induce apoptosis of PC-2 cells and enhance its radiosensitivity significantly. RNAi against survivin is of potential value in gene therapy of pancreatic cancer.

Knockdown of survivin expression by small interfering RNA suppresses proliferation of two human cancer cell lines.

OBJECTIVE: To construct an expression vector of small interfering RNA (siRNA) against survivin and observe its effects on survivin expression and proliferation of human pancreatic cancer cell line PC-2 and breast cancer cell line MCF-7. METHODS: Constructed an expression vector of siRNA against survivin and transfected it into PC-2 and MCF-7 cells using lipofectamine 2000. The expression of survivin was detected by semi-quantitive RT-PCR and immunohistochemistry, and its effects on proliferation of PC-2 and MCF-7 cells were detected by MTT assay. RESULTS: The introduction of sequence-specific siRNA could efficiently suppress survivin expression at both mRNA and protein levels in the two cancer cell lines. In PC-2 cells, the expression inhibition rates were 81.25% at mRNA level and 74.24% at protein level. In MCF-7 cells, the expression inhibition rates were 64.91% at mRNA level and 79.72% at protein level. The proliferation of PC-2 and MCF-7 cells was also suppressed, and 24 and 48 hours after the cells were reseeded, the proliferation inhibition rates of PC-2 cells were 28.00% and 33.38%, and that of MCF-7 cells were 31.58% and 33.02%, respectively. CONCLUSIONS: The expression vector of siRNA against survivin can block survivin expression in PC-2 and MCF-7 cells efficiently and specifically. Down regulation of survivin expression can suppress proliferation of PC-2 and MCF-7 cells. Survivin RNAi may have potential value in gene therapy of human cancers.

[Effects of siRNA targeted to survivin in suppressing proliferation and inducing apoptosis in breast cancer MCF-7 cells].

OBJECTIVE: Blocking the expression of survivin with RNA interference techniques, the effects of suppressing proliferation and inducing apoptosis of breast cancer MCF-7 cells were investigated. METHODS: A siRNA eukaryotic expression vector against survivin was constructed and transfected into breast cancer MCF-7 cells with lipofectamine 2000. The changes of survivin expression were detected by semi-quantitive RT-PCR and immunohistochemistry. The effect of suppressing proliferation of MCF-7 cell was detected by MTT assay. The effect of inducing MCF-7 cell apoptosis was detected by TUNEL assay. RESULTS: The sequence-specific siRNA can efficiently block the expression of survivin both at mRNA and protein levels. The expression inhibition rate was 64.9% at mRNA level detected by semi-quantitive RT-PCR and 79.7% at protein level detected by immunohistochemistry. Blocking the expression of survivin can suppress proliferation of MCF-7 cells significantly. At 24 and 48 h after the cells were reseeded, the proliferation inhibition rates were 31.6% and 33.0%, respectively. At 24 h after transfection, apoptosis was induced in 12.9% of the cells as detected by TUNEL assay. CONCLUSION: Blocking the expression of survivin with RNA interference technology can significantly suppress proliferation of MCF-7 cells and induce apoptosis to a certain degree. RNAi targeted to survivin has a potential value in gene therapy of breast cancer.