MiR-550a-3p promotes non-small cell lung cancer cell proliferation and metastasis through down-regulating TIMP2.

OBJECTIVE: MicroRNAs (miRNAs) have been identified to play a crucial regulatory role in the development and progression of malignant tumors, including lung cancer. However, the function of miR-550a-3p on the progression of non-small cell lung cancer (NSCLC) remains poorly understood. PATIENTS AND METHODS: Quantitative Real-time polymerase chain reaction was employed to estimate the expression level of miR-550a-3p in NSCLC tissue and cell samples. Cell proliferation was measured by using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) and colony formation assays. Transwell assay was recruited to demonstrate the abilities of cell invasion and migration. Luciferase analysis and Western-blot assay were performed to elucidate the underlying mechanism of miR-550a-3p in NSCLC. RESULTS: The level of miR-550a-3p expressed in NSCLC tissues was significantly higher than that in para-tumor control tissues. Over-expression of miR-550a-3p significantly promoted proliferation, invasion, and migration of A549 cells while knockdown of miR-550a-3p inhibited growth and metastasis of H460 cells. TIMP2 was verified as a direct target of miR-550a-3p in NSCLC. Restoration of TIMP2 rescued the influence of miR-550a-3p over-expression. CONCLUSIONS: We demonstrated that miR-550a-3p regulated the progression of NSCLC cells through TIMP2. Thus, miR-550a-3p axis could serve as a potential therapeutic target for NSCLC treatment.

Inhibitory effects of a dendritic cell vaccine loaded with radiation-induced apoptotic tumor cells on tumor cell antigens in mouse bladder cancer.

Herein, the preparation of a dendritic cell (DC) vaccine with radiation-induced apoptotic tumor cells and its immunological effects on bladder cancer in C57BL/6 mice was investigated. We used radiation to obtain a MB49 cell antigen that was sensitive to bone marrow-derived DCs to prepare a DC vaccine. An animal model of tumor-bearing mice was established with the MB49 mouse bladder cancer cell line. Animals were randomly allocated to an experimental group or control group. DC vaccine or phosphate-buffered saline was given 7 days before inoculation with tumor cells. Each group consisted of 2 subgroups in which tumor volume and the survival of tumor-bearing mice were recorded. Tumor volumes and average tumor masses of mice administered DC vaccine loaded with radiation-induced apoptotic cells were significantly lower than those in the control group (P < 0.01). Survival in the experimental group was also longer than that in the control group, and 2 mice survived without tumor formation. In the DC vaccine group, 2 mice were alive without tumor growth after 30 days, and no tumor was observed at 30 days after subcutaneous inoculation of MB49 cells. The DC vaccine loaded with radiation-induced apoptotic tumor cells had an anti-tumor effect and was associated with increased survival in a bladder cancer model in mice.

Facile synthesis of pentacle gold-copper alloy nanocrystals and their plasmonic and catalytic properties.

The combination of gold and copper is a good way to pull down the cost of gold and ameliorate the instability of copper. Through shape control, the synergy of these two metals can be better exploited. Here, we report an aqueous phase route to the synthesis of pentacle gold-copper alloy nanocrystals with fivefold twinning, the size of which can be tuned in the range from 45 to 200 nm. The growth is found to start from a decahedral core, followed by protrusion of branches along twinning planes. Pentacle products display strong localized surface plasmon resonance peaks in the near-infrared region. Under irradiation by an 808-nm laser, 70-nm pentacle nanocrystals exhibit a notable photothermal effect to kill 4T1 murine breast tumours established on BALB/c mice. In addition, 70-nm pentacle nanocrystals show better catalytic activity than conventional citrate-coated 5-nm Au nanoparticles towards the reduction of p-nitrophenol to p-aminophenol by sodium borohydride.

Construction of carbon-based two-dimensional crystalline nanostructure by chemical vapor deposition of benzene on Cu(111).

A new carbon-based two-dimensional crystalline nanostructure was discovered. The nanostructure was facilely constructed by chemical vapor deposition of benzene on Cu(111) in an ultrahigh vacuum chamber. A low temperature scanning tunneling microscopy and spectroscopy study of the nanostructure indicated that it has an orthorhombic superstructure and a semiconductor character with an energy gap of 0.8 eV. An X-ray photoelectron spectroscopy study showed that C-C(sp(2)) bonding is predominantly preserved, suggesting a framework consisting of π-conjugated building blocks. The periodic nanostructure was found to be a surprisingly excellent template for isolating and stabilizing magnetic atoms: Co atoms deposited on it can be well dispersed and form locally ordered atomic chains with their atomic magnetism preserved. Therefore the nanostructure may be suitable for organic spintronic applications. The most likely structural model for the nanostructure is proposed with the aid of density functional theory calculations and simulations, suggesting that the 2D nanostructure may consist of polyphenylene chains interconnected by Cu adatoms.

One-dimensional transition metal-benzene sandwich polymers: possible ideal conductors for spin transport.

We investigate the electronic and magnetic properties of the proposed one-dimensional transition metal (TM = Sc, Ti, V, Cr, and Mn) -benzene (Bz) sandwich polymers by means of density functional calculations. [V(Bz)](infinity) is found to be a quasi-half-metallic ferromagnet, and half-metallic ferromagnetism is predicted for [Mn(Bz)](infinity). Moreover, we show that stretching the [TM(Bz)](infinity) polymers could have dramatic effects on their electronic and magnetic properties. The elongated [V(Bz)](infinity) displays half-metallic behavior, and [Mn(Bz)](infinity) stretched to a certain degree becomes an antiferromagnetic insulator. The possibilities to stabilize the ferromagnetic order in [V(Bz)](infinity) and [Mn(Bz)](infinity) polymers at finite temperatures are discussed. We suggest that the hexagonal bundles composed by these polymers might display intrachain ferromagnetic order at finite temperatures by introducing interchain exchange coupling.

Synthesis and Characterization of Aligned ZnO Nanorods on Porous Aluminum Oxide Template.

Aligned high-density ZnO nanorods were successfully synthesized on porous aluminum oxide (PAO) template. The growth process involves carbonthermal reduction of ZnO as a Zn vapor source and ZnO nucleation on the PAO template without metal catalysts. Field-emission scanning electron microscope images revealed that the nanorods have uniform length distributions and hexagon end planes, and the intense c-axis growth was also confirmed by X-ray diffraction. Strong ultraviolet emission at 380 nm and weak green band emission at 520 nm at room-temperature photoluminescence clearly indicated the high quality of the ZnO nanorods. A growth mechanism is proposed that the multipore surface of the PAO template plays a critical role in the nucleation of ZnO in the initial stage of growth, and nanorods grow from the nuclei due to intense ZnO c-axis orientation growth.

Intraurethral brachytherapy for prevention of recurrent urethral stricture after internal urethrotomy or transurethral resection of scar.

BACKGROUND PURPOSE: Restricture after internal urethrotomy is the major limitation to the long-term success of the procedure. The objective of this study was to evaluate the effect of intraurethral brachytherapy after internal urethrotomy or transurethral scar resection on recurrent urethral stricture. PATIENTS AND METHODS: From January 1998 to June 1999, catheter-based intraurethral brachytherapy with 192-iridium was performed in 17 patients with recurrent urethral stricture to prevent restricture after internal urethrotomy or transurethral resection of scar. The radiation was repeated within 3 days after surgery to reach a total dosage of 1000 to 1500 cGy. RESULTS: During the follow-up (range 14-27 months; mean 20 months), two patients had dysuria, including one patient with an atonic detrusor muscle. The other patient needed self-dilation. Fifteen patients presented normal voiding. The stricture recurred 3 months later in only one patient, so the restricture rate is 7%. No significant complication was observed associated with brachytherapy during the follow-up. CONCLUSION: Intraurethral brachytherapy after internal urethrotomy or transurethral resection of scar is a safe and effective treatment for recurrent urethral strictures.

Basic fibroblast growth factor stimulation of glial cells protects dopamine neurons from 6-hydroxydopamine toxicity: involvement of the glutathione system.

Neurotrophic factors have been shown to support the survival and promote the recovery of injured neurons both in vivo and in vitro. Here, we investigated whether glial cell line-derived neurotrophic factor (GDNF) and basic fibroblast growth factor (bFGF) could modify the damage to dopamine (DA) neurons in mesencephalic cultures caused by the neurotoxin 6-hydroxydopamine (6-OHDA). The data show that bFGF, but not GDNF, effectively protected DA neurons from 6-OHDA toxicity. Because bFGF is a glial mitogen, whereas GDNF is not, we tested whether glial cells participated in bFGF neuroprotection. Inhibition of glial cell proliferation completely prevented the protective effect of bFGF. Because oxidative events have been associated with 6-OHDA-induced damage, we examined the levels of glutathione (GSH) in control and bFGF-treated cultures. Cultures treated with bFGF had higher levels of GSH, which increased even further in response to 6-OHDA exposure. Control cultures failed to up-regulate GSH levels after 6-OHDA, suggesting a relationship between increased GSH levels and protection from 6-OHDA. Inhibition of glial cell proliferation prevented the rise in GSH in bFGF-treated cultures and abolished the increase after 6-OHDA treatment. Protection from 6-OHDA by bFGF was also diminished when GSH levels were decreased by the GSH synthesis inhibitor L-buthionine sulfoximine. Our study shows that stimulation of glial cells by bFGF allows the up-regulation of antioxidant defenses and supports cell survival during oxidative stress.